Editing Bacillus

{{Short description|Genus of bacteria}}
{{about|the bacterium|a hypernymic category|bacillus (shape)|the stick-insect genus|Bacillus (insect)}}
{{cs1 config|name-list-style=vanc|display-authors=6}}
{{Automatic taxobox
| image = Bacillus subtilis Gram.jpg
| image_caption = ''[[Bacillus subtilis]]'', stained
| taxon = Bacillus
| authority = [[Ferdinand Cohn|Cohn]] 1872
| type_species = ''[[Bacillus subtilis]]''
| type_species_authority = (Ehrenberg 1835) [[Ferdinand Cohn|Cohn]] 1872
| subdivision_ranks = Species
| subdivision_ref = <ref name=LPSN/>
| subdivision = [[#Phylogeny|See text]]
}}

'''''Bacillus''''' (Latin "stick") is a [[genus]] of [[Gram-positive]], rod-shaped [[bacteria]], a member of the phylum ''[[Bacillota]]'', with 266 named [[species]]. The term is also used to describe [[bacillus (shape)|the shape (rod)]] of other so-shaped bacteria; and the plural ''Bacilli'' is the name of the [[class (biology)|class]] of bacteria to which this genus belongs. ''Bacillus'' species can be either [[obligate aerobe]]s which are dependent on [[oxygen]], or [[facultative anaerobes]] which can survive in the absence of oxygen. Cultured ''Bacillus'' species test positive for the [[enzyme]] [[catalase]] if oxygen has been used or is present.<ref name="Turnbull_1996">{{cite book | vauthors = Turnbull PC | chapter = Bacillus | title = Barron's Medical Microbiology | veditors = Baron S, etal | edition = 4th | publisher = Univ of Texas Medical Branch | year = 1996 | pmid = 21413260 | chapter-url = https://www.ncbi.nlm.nih.gov/books/NBK7699/ | isbn = 978-0-9631172-1-2 }}</ref>

''Bacillus'' can reduce themselves to oval [[endospore]]s and can remain in this dormant state for years. The endospore of one species from Morocco is reported to have survived being heated to 420&nbsp;°C.<ref name="Beladjal_2018">{{cite journal | vauthors = Beladjal L, Gheysens T, Clegg JS, Amar M, Mertens J | title = Life from the ashes: survival of dry bacterial spores after very high temperature exposure | journal = Extremophiles: Life Under Extreme Conditions | volume = 22 | issue = 5 | pages = 751–759 | date = September 2018 | pmid = 29869718 | doi = 10.1007/s00792-018-1035-6 | s2cid = 46935396 }}</ref> Endospore formation is usually triggered by a lack of nutrients: the bacterium divides within its cell wall, and one side then engulfs the other. They are not true [[spore]]s (i.e., not an offspring).<ref>{{cite web | title = Bacterial Endospores | url = https://cals.cornell.edu/microbiology/research/active-research-labs/angert-lab/epulopiscium/bacterial-endospores | work = Cornell University College of Agriculture and Life Sciences, Department of Microbiology | access-date = 21 October 2018 }}</ref>  Endospore formation originally defined the genus, but not all such species are closely related, and many species have been moved to other genera of the ''Bacillota''.<ref name=Brock>{{cite book | veditors = Madigan M, Martinko J | title = Brock Biology of Microorganisms | edition = 11th | publisher = Prentice Hall | year = 2005 | isbn = 978-0-13-144329-7 }}</ref> Only one endospore is formed per cell. The spores are resistant to heat, cold, radiation, desiccation, and disinfectants. ''Bacillus anthracis'' needs oxygen to sporulate; this constraint has important consequences for epidemiology and control.<ref name=":1">{{cite book | vauthors = Turnbull PC | chapter = Bacillus |date=1996 | title = Medical Microbiology | veditors = Baron S | chapter-url = http://www.ncbi.nlm.nih.gov/books/NBK7699/ |access-date=2024-03-18 |edition=4th |place=Galveston (TX) |publisher=University of Texas Medical Branch at Galveston |isbn=978-0-9631172-1-2 |pmid=21413260}}</ref> In vivo, ''B. anthracis'' produces a polypeptide (polyglutamic acid) capsule that kills it from phagocytosis.<ref name=":1" /> The genera ''Bacillus'' and ''Clostridium'' constitute the family ''Bacillaceae''. Species are identified by using morphologic and biochemical criteria.<ref name="Turnbull_1996" /> Because the spores of many ''Bacillus'' species are resistant to heat, radiation, disinfectants, and desiccation, they are difficult to eliminate from medical and pharmaceutical materials and are a frequent cause of contamination. Not only are they resistant to heat, radiation, etc., but they are also resistant to chemicals such as antibiotics.<ref name="sciencedirect.com">{{cite journal | vauthors = Christie G, Setlow P | title = Bacillus spore germination: Knowns, unknowns and what we need to learn | journal = Cellular Signalling | volume = 74 | pages = 109729 | date = October 2020 | pmid = 32721540 | doi = 10.1016/j.cellsig.2020.109729 | doi-access = free }}</ref> This resistance allows them to survive for many years and especially in a controlled environment.<ref name="sciencedirect.com"/> ''Bacillus'' species are well known in the food industries as troublesome spoilage organisms.<ref name="Turnbull_1996"/>

Ubiquitous in nature, ''Bacillus'' includes [[Symbiosis|symbiotic]] (sometimes referred to as [[endophyte]]s) as well as independent species. Two species are medically significant: ''[[Bacillus anthracis|B. anthracis]]'' causes [[anthrax]];<ref>{{cite journal | vauthors = Spencer RC | title = Bacillus anthracis | journal = Journal of Clinical Pathology | volume = 56 | issue = 3 | pages = 182–187 | date = March 2003 | pmid = 12610093 | pmc = 1769905 | doi = 10.1136/jcp.56.3.182 }}</ref> and ''[[Bacillus cereus|B. cereus]]'' causes [[foodborne illness|food poisoning]].<ref>{{cite journal | vauthors = Schoeni JL, Wong AC | title = Bacillus cereus food poisoning and its toxins | journal = Journal of Food Protection | volume = 68 | issue = 3 | pages = 636–648 | date = March 2005 | pmid = 15771198 | doi = 10.4315/0362-028X-68.3.636 | doi-access = free }}</ref>

Many species of ''Bacillus'' can produce copious amounts of enzymes, which are used in various industries, such as in the production of [[alpha amylase]] used in starch hydrolysis and the [[protease]] [[subtilisin]] used in [[detergent]]s. ''[[B. subtilis]]'' is a valuable model for bacterial research. Some ''Bacillus'' species can synthesize and secrete [[lipopeptide]]s, in particular [[surfactin]]s and [[mycosubtilin]]s.<ref>{{cite journal | vauthors = Nigris S, Baldan E, Tondello A, Zanella F, Vitulo N, Favaro G, Guidolin V, Bordin N, Telatin A, Barizza E, Marcato S, Zottini M, Squartini A, Valle G, Baldan B | title = Biocontrol traits of Bacillus licheniformis GL174, a culturable endophyte of Vitis vinifera cv. Glera | journal = BMC Microbiology | volume = 18 | issue = 1 | pages = 133 | date = October 2018 | pmid = 30326838 | pmc = 6192205 | doi = 10.1186/s12866-018-1306-5 | doi-access = free }}</ref><ref>{{cite journal | vauthors = Favaro G, Bogialli S, Di Gangi IM, Nigris S, Baldan E, Squartini A, Pastore P, Baldan B | title = Characterization of lipopeptides produced by Bacillus licheniformis using liquid chromatography with accurate tandem mass spectrometry | journal = Rapid Communications in Mass Spectrometry | volume = 30 | issue = 20 | pages = 2237–2252 | date = October 2016 | pmid = 27487987 | doi = 10.1002/rcm.7705 | bibcode = 2016RCMS...30.2237F }}</ref><ref name="Paul_2021" /> ''Bacillus'' species are also found in marine [[sponge]]s.<ref name="Paul_2021" /> Marine sponge associated ''Bacillus subtilis'' (strains WS1A and YBS29) can synthesize several antimicrobial peptides.<ref name="Paul_2021" /><ref>{{cite journal | vauthors = Rahman MM, Paul SI, Akter T, Tay AC, Foysal MJ, Islam MT | title = Whole-Genome Sequence of Bacillus subtilis WS1A, a Promising Fish Probiotic Strain Isolated from Marine Sponge of the Bay of Bengal | journal = Microbiology Resource Announcements | volume = 9 | issue = 39 | pages = e00641–20 | date = September 2020 | pmid = 32972930 | pmc = 7516141 | doi = 10.1128/MRA.00641-20 }}</ref> These ''Bacillus subtilis'' strains can develop disease resistance in ''[[Rohu|Labeo rohita]]''.<ref name="Paul_2021" />

==Structure==
=== Cell wall ===
[[File:Bacillus subtilis 2.jpg|''Bacillus subtilis'' ([[Gram stain]])|right|thumb]]
The cell wall of ''Bacillus'' is a structure on the outside of the cell that forms the second barrier between the bacterium and the environment, and at the same time maintains the rod shape and withstands the pressure generated by the cell's [[turgor]]. The cell wall is made of [[teichoic acid|teichoic]] and teichuronic acids. ''B. subtilis'' is the first bacterium for which the role of an [[actin]]-like [[cytoskeleton]] in cell shape determination and [[peptidoglycan]] synthesis was identified and for which the entire set of peptidoglycan-synthesizing enzymes was localized. The role of the cytoskeleton in shape generation and maintenance is important.<ref>{{cite journal | vauthors = Shih YL, Rothfield L | title = The bacterial cytoskeleton | journal = Microbiology and Molecular Biology Reviews | volume = 70 | issue = 3 | pages = 729–754 | date = September 2006 | pmid = 16959967 | pmc = 1594594 | doi = 10.1128/MMBR.00017-06 }}</ref>

''Bacillus'' species are rod-shaped, endospore-forming aerobic or facultatively anaerobic, Gram-positive bacteria; in some species cultures may turn Gram-negative with age. The many species of the genus exhibit a wide range of physiologic abilities that allow them to live in every natural environment. Only one endospore is formed per cell. The spores are resistant to heat, cold, radiation, desiccation, and disinfectants.<ref name="Turnbull_1996"/>

== Origin of name ==
The genus ''Bacillus'' was named in 1835 by [[Christian Gottfried Ehrenberg]], to contain rod-shaped (bacillus) bacteria. He had seven years earlier named the genus ''[[Bacterium (genus)|Bacterium]]''. ''Bacillus'' was later amended by [[Ferdinand Cohn]] to further describe them as spore-forming, Gram-positive, aerobic or facultatively anaerobic bacteria.<ref name="Cohn_1872">{{cite journal | vauthors = Cohn F | title = Untersuchungen über Bakterien. | journal = Beiträge zur Biologie der Pflanzen | trans-title = Studies on Bacteria. | trans-journal = Contributions to the Biology of Plants | language = DE | volume = 2 | date = 1872 | issue = 1 | pages = 127–224 }}</ref> Like other genera associated with the early history of microbiology, such as ''[[Pseudomonas]]'' and ''[[Vibrio]]'', the 266 species of ''Bacillus'' are ubiquitous.<ref>{{lpsn|b/bacillus.html|Bacillus|vanc}}</ref> The genus has a very large [[ribosomal]] [[16S ribosomal RNA|16S]] diversity.<ref>{{cite journal | vauthors = Pei AY, Oberdorf WE, Nossa CW, Agarwal A, Chokshi P, Gerz EA, Jin Z, Lee P, Yang L, Poles M, Brown SM, Sotero S, Desantis T, Brodie E, Nelson K, Pei Z | title = Diversity of 16S rRNA genes within individual prokaryotic genomes | journal = Applied and Environmental Microbiology | volume = 76 | issue = 12 | pages = 3886–3897 | date = June 2010 | pmid = 20418441 | pmc = 2893482 | doi = 10.1128/AEM.02953-09 | bibcode = 2010ApEnM..76.3886P }}</ref>

==Isolation and identification==
Established methods for isolating ''Bacillus'' species for culture primarily involve suspension of sampled soil in distilled water, heat shock to kill off vegetative cells leaving primarily viable spores in the sample, and culturing on agar plates with further tests to confirm the identity of the cultured colonies.<ref>{{cite journal | vauthors = Travers RS, Martin PA, Reichelderfer CF | title = Selective Process for Efficient Isolation of Soil Bacillus spp | journal = Applied and Environmental Microbiology | volume = 53 | issue = 6 | pages = 1263–1266 | date = June 1987 | pmid = 16347359 | pmc = 203852 | doi = 10.1128/aem.53.6.1263-1266.1987 | bibcode = 1987ApEnM..53.1263T }}</ref> Additionally, colonies which exhibit characteristics typical of ''Bacillus'' bacteria can be selected from a culture of an environmental sample which has been significantly diluted following heat shock or hot air drying to select potential ''Bacillus'' bacteria for testing.<ref>{{cite journal | vauthors = Foysal MJ, Lisa AK | title = Isolation and characterization of ''Bacillus'' sp. strain BC01 from soil displaying potent antagonistic activity against plant and fish pathogenic fungi and bacteria | journal = Journal, Genetic Engineering & Biotechnology | volume = 16 | issue = 2 | pages = 387–392 | date = December 2018 | pmid = 30733751 | pmc = 6353715 | doi = 10.1016/j.jgeb.2018.01.005 }}</ref>

Cultured colonies are usually large, spreading, and irregularly shaped. Under the microscope, the ''Bacillus'' cells appear as rods, and a substantial portion of the cells usually contain oval [[endospore]]s at one end, making them bulge.<ref>{{Cite book | vauthors = Caldwell FE |url=https://books.google.com/books?id=MpBpAwAAQBAJ&dq=Bacillus+cells+appear+as+rods%2C+and+a+substantial+portion+of+the+cells+usually+contain+oval+endospores+at+one+end%2C&pg=PA35 |title=The Students Reference Guide to Bacteria |date=2011-04-06 |publisher= Lulu.com|isbn=978-1-257-42416-0 |language=en}}</ref>

== Characteristics of ''Bacillus'' spp. ==
S.I. Paul et al. (2021)<ref name="Paul_2021">{{cite journal | vauthors = Paul SI, Rahman MM, Salam MA, Khan MA, Islam MT |date=2021-12-15|title=Identification of marine sponge-associated bacteria of the Saint Martin's island of the Bay of Bengal emphasizing on the prevention of motile Aeromonas septicemia in Labeo rohita |journal= Aquaculture |volume=545 |pages=737156 |doi=10.1016/j.aquaculture.2021.737156 |bibcode=2021Aquac.54537156P }}</ref> isolated and identified multiple strains of ''[[Bacillus subtilis]]'' (strains WS1A,<ref>{{cite journal | url = https://www.ncbi.nlm.nih.gov/nuccore/MK910097.1/ | title = Bacillus subtilis strain WS1A | journal = GenBank | date = 19 May 2019 | publisher = U.S. National Library of Medicine }}</ref> YBS29,<ref>{{cite journal | url = https://www.ncbi.nlm.nih.gov/nuccore/MT605348.1/| title = Bacillus subtilis strain YBS29 | journal = GenBank | date = 19 June 2020 | publisher = U.S. National Library of Medicine }}</ref> KSP163A,<ref>{{cite journal | url = https://www.ncbi.nlm.nih.gov/nuccore/MK910103.1/ | title = Bacillus subtilis strain KSP163A | journal = GenBank | date = 19 May 2019 | publisher = U.S. National Library of Medicine }}</ref> OA122,<ref>{{cite journal | url = https://www.ncbi.nlm.nih.gov/nuccore/MT611945.1/ | title = Bacillus subtilis strain OA122 | journal = GenBank | date = 20 June 2020 | publisher = U.S. National Library of Medicine }}</ref> ISP161A,<ref>{{cite journal | url = https://www.ncbi.nlm.nih.gov/nuccore/MT611943.1/ | title = Bacillus subtilis strain ISP161A | journal = GenBank | date = 20 June 2020 | publisher = U.S. National Library of Medicine }}</ref> OI6,<ref>{{cite journal | url = https://www.ncbi.nlm.nih.gov/nuccore/MT605347.1/ | title = Bacillus subtilis strain OI6 | journal = GenBank | date = 19 June 2020 | publisher = U.S. National Library of Medicine }}</ref> WS11,<ref>{{cite journal | url = https://www.ncbi.nlm.nih.gov/nuccore/MK910101.1/ | title = Bacillus subtilis strain WS11 | journal = GenBank | date = 19 May 2019 | publisher = U.S. National Library of Medicine }}</ref> KSP151E,<ref>{{cite journal | url = https://www.ncbi.nlm.nih.gov/nuccore/MT605346.1/ | title = Bacillus subtilis strain KSP151E | journal = GenBank | date = 19 June 2020 | publisher = U.S. National Library of Medicine }}</ref> and S8,<ref>{{cite journal | url = https://www.ncbi.nlm.nih.gov/nuccore/MT611946.1/ | title = Bacillus subtilis strain S8 | journal = GenBank | date = 20 June 2020 | publisher = U.S. National Library of Medicine }}</ref>) from [[Sponge|marine sponges]] of the [[St. Martin's Island|Saint Martin's Island]] Area of the [[Bay of Bengal]], [[Bangladesh]]. Based on their study, colony, morphological, physiological, and biochemical characteristics of ''Bacillus'' spp. are shown in the Table below.<ref name="Paul_2021" />
{| class="wikitable"
! Test type
! Test
! Characteristics
|-
| rowspan="4" |Colony characters
|Size
|Medium
|-
|Type
|Round
|-
|Color
|Whitish
|-
|Shape
|Convex
|-
|Morphological characters
|Shape
|Rod
|-
| rowspan="2" |Physiological characters
|Motility
|<nowiki>+</nowiki>
|-
|Growth at 6.5% NaCl
|<nowiki>+</nowiki>
|-
| rowspan="12" |Biochemical characters
|Gram's staining
|<nowiki>+</nowiki>
|-
|Oxidase
|<nowiki>-</nowiki>
|-
|Catalase
|<nowiki>+</nowiki>
|-
|Oxidative-Fermentative
|O/F
|-
|Motility
|<nowiki>+</nowiki>
|-
|Methyl Red
|<nowiki>+</nowiki>
|-
|Voges-Proskauer
|<nowiki>-</nowiki>
|-
|Indole
|<nowiki>-</nowiki>
|-
|H<sub>2</sub>S Production
|<nowiki>+/–</nowiki>
|-
|Urease
|<nowiki>-</nowiki>
|-
|Nitrate reductase
|<nowiki>+</nowiki>
|-
|β-Galactosidase
|<nowiki>+</nowiki>
|-
| rowspan="6" |Hydrolysis of
|Gelatin
|<nowiki>+</nowiki>
|-
|Aesculin
|<nowiki>+</nowiki>
|-
|Casein
|<nowiki>+</nowiki>
|-
|Tween 40
|<nowiki>+</nowiki>
|-
|Tween 60
|<nowiki>+</nowiki>
|-
|Tween 80
|<nowiki>+</nowiki>
|-
| rowspan="13" |Acid production from
|Glycerol
|<nowiki>+</nowiki>
|-
|Galactose
|<nowiki>+</nowiki>
|-
|D-Glucose
|<nowiki>+</nowiki>
|-
|D-Fructose
|<nowiki>+</nowiki>
|-
|D-Mannose
|<nowiki>+</nowiki>
|-
|Mannitol
|<nowiki>+</nowiki>
|-
|N-Acetylglucosamine
|<nowiki>+</nowiki>
|-
|Amygdalin
|<nowiki>+</nowiki>
|-
|Maltose
|<nowiki>+</nowiki>
|-
|D-Melibiose
|<nowiki>+</nowiki>
|-
|D-Trehalose
|<nowiki>+</nowiki>
|-
|Glycogen
|<nowiki>+</nowiki>
|-
|D-Turanose
|<nowiki>+</nowiki>
|}
Note: + = Positive, – =Negative, O= Oxidative, F= Fermentative

==Phylogeny==
It's been long known that the (pre-2020) definition of ''Bacillus'' is overly vague.<ref name=Ash/>
* Xu and Côté (2003) uses 16S and ITS rRNA regions to divide the genus ''Bacillus'' into 10 groups, including the nested genera ''[[Paenibacillus]]'', ''[[Brevibacillus]]'', ''[[Geobacillus]]'', ''Marinibacillus'' and ''[[Virgibacillus]]''.<ref>{{cite journal | vauthors = Xu D, Côté JC | title = Phylogenetic relationships between Bacillus species and related genera inferred from comparison of 3' end 16S rDNA and 5' end 16S-23S ITS nucleotide sequences | journal = International Journal of Systematic and Evolutionary Microbiology | volume = 53 | issue = Pt 3 | pages = 695–704 | date = May 2003 | pmid = 12807189 | doi = 10.1099/Ijs.0.02346-0 | doi-access = free }}</ref>
* Ash and Carol (2008) also uses 16S rRNA and found extensive "phylogenetic heterogenity".<ref name=Ash>{{Cite journal|last1=Ash|first1=Carol|last2=Farrow|first2=J.A.E.|last3=Wallbanks|first3=Sally|last4=Collins|first4=M.D.|date=28 June 2008|title=Phylogenetic heterogeneity of the genus Bacillus revealed by comparative analysis of small-subunit-ribosomal RNA sequences|url=http://dx.doi.org/10.1111/j.1472-765x.1991.tb00608.x|journal=Letters in Applied Microbiology|volume=13|issue=4|pages=202–206|doi=10.1111/j.1472-765x.1991.tb00608.x|s2cid=82988953|issn=0266-8254}}</ref> 
* [['The All-Species Living Tree' Project]], which has been in operation since 2008, also maintains a 16S (and 23S if available) tree of all validated species.<ref>{{cite journal | vauthors = Yarza P, Richter M, Peplies J, Euzeby J, Amann R, Schleifer KH, Ludwig W, Glöckner FO, Rosselló-Móra R | title = The All-Species Living Tree project: a 16S rRNA-based phylogenetic tree of all sequenced type strains | journal = Systematic and Applied Microbiology | volume = 31 | issue = 4 | pages = 241–250 | date = September 2008 | pmid = 18692976 | doi = 10.1016/j.syapm.2008.07.001 | hdl-access = free | hdl = 10261/103580 | url = https://tede.ufrrj.br/jspui/handle/jspui/5297 }}</ref><ref>{{cite journal | vauthors = Yarza P, Ludwig W, Euzéby J, Amann R, Schleifer KH, Glöckner FO, Rosselló-Móra R | title = Update of the All-Species Living Tree Project based on 16S and 23S rRNA sequence analyses | journal = Systematic and Applied Microbiology | volume = 33 | issue = 6 | pages = 291–299 | date = October 2010 | pmid = 20817437 | doi = 10.1016/j.syapm.2010.08.001 | hdl = 10261/54801 }}</ref><ref>{{cite journal | vauthors = Munoz R, Yarza P, Ludwig W, Euzéby J, Amann R, Schleifer KH, Glöckner FO, Rosselló-Móra R | title = Release LTPs104 of the all-species living tree | journal = Systematic and Applied Microbiology | date = May 2011 | volume = 34 | issue = 3 | pages = 169–70 | doi = 10.1016/j.syapm.2011.03.001 | pmid = 21497273 | url = http://www.arb-silva.de/fileadmin/silva_databases/living_tree/LTP_release_104/LTPs104_SSU_tree.pdf | archive-url = https://web.archive.org/web/20150923172916/http://www.arb-silva.de/fileadmin/silva_databases/living_tree/LTP_release_104/LTPs104_SSU_tree.pdf | archive-date = 23 September 2015 }}</ref> In this tree, the genus ''Bacillus'' contains a very large number of nested taxa and majorly in both 16S and 23S. It is [[paraphyletic]] to the [[Lactobacillales]] (''Lactobacillus, Streptococcus, Staphylococcus, Listeria'', etc.), due to ''[[Bacillus coahuilensis]]'' and others.<ref>{{cite journal | vauthors = Salvetti E, Harris HM, Felis GE, O'Toole PW | title = Comparative Genomics of the Genus Lactobacillus Reveals Robust Phylogroups That Provide the Basis for Reclassification | journal = Applied and Environmental Microbiology | volume = 84 | issue = 17 | date = September 2018 | pmid = 29915113 | pmc = 6102987 | doi = 10.1128/AEM.00993-18 | bibcode = 2018ApEnM..84E.993S | veditors = Björkroth J }}</ref>
* Alcaraz ''et al.'' 2010 presents a gene [[concatenation]] study, which found results similar to the All-Species Living Tree, but with a much more limited number of species in terms of groups.<ref name="Alcaraz2010">{{cite journal | vauthors = Alcaraz LD, Moreno-Hagelsieb G, Eguiarte LE, Souza V, Herrera-Estrella L, Olmedo G | title = Understanding the evolutionary relationships and major traits of Bacillus through comparative genomics | journal = BMC Genomics | volume = 11 | pages = 332 | date = May 2010 | pmid = 20504335 | pmc = 2890564 | doi = 10.1186/1471-2164-11-332 | id = 1471216411332 | doi-access = free }}</ref> (This scheme used ''Listeria'' as an outgroup, so in light of the ARB tree, it may be "inside-out").
* Gupta ''et al.'' 2020<ref name="Gupta20">{{Cite journal|last1=Gupta|first1=Radhey S.|last2=Patel|first2=Sudip|last3=Saini|first3=Navneet|last4=Chen|first4=Shu|date=1 November 2020|title=Robust demarcation of 17 distinct Bacillus species clades, proposed as novel Bacillaceae genera, by phylogenomics and comparative genomic analyses: description of Robertmurraya kyonggiensis sp. nov. and proposal for an emended genus ''Bacillus'' limiting it only to the members of the ''subtilis'' and ''cereus'' clades of species|journal=International Journal of Systematic and Evolutionary Microbiology|language=en|volume=70|issue=11|pages=5753–5798|doi=10.1099/ijsem.0.004475|pmid=33112222|issn=1466-5026|doi-access=free}}</ref> and Patel ''et al.'' 2020<ref name="Patel20">{{Cite journal|last1=Patel|first1=Sudip|last2=Gupta|first2=Radhey S.|date=1 January 2020|title=A phylogenomic and comparative genomic framework for resolving the polyphyly of the genus Bacillus: Proposal for six new genera of Bacillus species, Peribacillus gen. nov., Cytobacillus gen. nov., Mesobacillus gen. nov., Neobacillus gen. nov., Metabacillus gen. nov. and Alkalihalobacillus gen. nov.|journal=International Journal of Systematic and Evolutionary Microbiology|language=en|volume=70|issue=1|pages=406–438|doi=10.1099/ijsem.0.003775|pmid=31617837|issn=1466-5026|doi-access=free}}</ref> use [[phylogenomics]] and [[comparative genomics]] to resolve the structure in ''Bacillus'' sensu lato. They propose (and '''[[Validly published name|validly publish]]''') a number of new genus names, thereby restricting ''Bacillus'' has been restricted to only include species closely related to ''[[Bacillus subtilis]]'' and ''[[Bacillus cereus]].''<ref name="Patel20"/> (This does not make the genus monophyletic, however: a number of nested genera persists between the two groups.)<ref name="Gupta20"/> The newly created genera are: ''[[Peribacillus]]'', ''[[Cytobacillus]]'', ''[[Mesobacillus]]'', ''[[Neobacillus]]'', ''[[Metabacillus]]'', ''[[Alkalihalobacillus]]'', ''[[Alteribacter]]'', ''[[Ectobacillus]]'', ''[[Evansella]]'', ''[[Ferdinandcohnia]]'', ''[[Gottfriedia]]'', ''[[Heyndrickxia]]'', ''[[Lederbergia]]'', ''[[Litchfieldia]]'', ''[[Margalitia]]'', ''[[Niallia]]'', ''[[Priestia]]'', ''[[Robertmurraya]]'', ''[[Rossellomorea]]'', ''[[Schinkia]]'', ''[[Siminovitchia]]'', ''[[Sutcliffiella]]'' and ''[[Weizmannia]]''.
* Nikolaidis ''et al.'' 2022 studied 1104 ''Bacillus'' proteomes using a gene concatenation based on 114 core proteins and delineated the relationships among the various species, defined as ''Bacillus'' from the NCBI taxonomy.<ref name=":0">{{cite journal | vauthors = Nikolaidis M, Hesketh A, Mossialos D, Iliopoulos I, Oliver SG, Amoutzias GD | title = A Comparative Analysis of the Core Proteomes within and among the ''Bacillus subtilis'' and ''Bacillus cereus'' Evolutionary Groups Reveals the Patterns of Lineage- and Species-Specific Adaptations | journal = Microorganisms | volume = 10 | issue = 9 | pages = 1720 | date = August 2022 | pmid = 36144322 | pmc = 9505155 | doi = 10.3390/microorganisms10091720 | doi-access = free }}</ref> The various strains were clustered into species, based on Average Nucleotide identity (ANI) values, with a species cutoff of 95%.<ref name=":0" />

One clade, formed by ''Bacillus anthracis'', ''Bacillus cereus'', ''Bacillus mycoides'', ''Bacillus pseudomycoides'', ''Bacillus thuringiensis'', and ''Bacillus weihenstephanensis'' under the 2011 classification standards, should be a single species (within 97% 16S identity), but for medical reasons, they are considered separate species<ref>{{cite book | vauthors = Økstad OA, Kolstø AB | chapter = Chapter 2: Genomics of Bacillus species | veditors = Wiedmann M, Zhang W | title = Genomics of Foodborne Bacterial Pathogens | date = December 2010 | pages = 29–53 (34–35) | location = New York, NY | publisher = Springer | doi = 10.1007/978-1-4419-7686-4_2 | isbn = 978-1-4419-7686-4 | volume = 29 | series = Food Microbiology and Food Safety }}</ref> (an issue also present for four species of ''[[Shigella]]'' and ''[[Escherichia coli]]'').<ref>{{cite book | vauthors = Brenner DJ | chapter = Family I. Enterobacteriaceae Rahn 1937, Nom. fam. cons. Opin. 15, Jud. Com. 1958, 73; Ewing, Farmer, and Brenner 1980, 674; Judicial Commission 1981, 104. | veditors = Krieg NR, Holt JG | title = Bergey's Manual of Systematic Bacteriology | edition = first | volume = 1 | publisher = The Williams & Wilkins Co | location = Baltimore| date = 1984 | pages = 408–420 }}</ref>

{| class="wikitable"
|-
! colspan=1 | Alcaraz et al. 2010<ref name="Alcaraz2010"/>
! colspan=1 | 16S rRNA based [[The All-Species Living Tree Project|LTP]]_10_2024<ref>{{cite web |title=The LTP |url=https://imedea.uib-csic.es/mmg/ltp/#LTP| access-date=10 December 2024}}</ref><ref>{{cite web |title=LTP_all tree in newick format |url=https://imedea.uib-csic.es/mmg/ltp/wp-content/uploads/ltp/LTP_all_10_2024.ntree |access-date=10 December 2024}}</ref><ref>{{cite web |title=LTP_10_2024 Release Notes |url=https://imedea.uib-csic.es/mmg/ltp/wp-content/uploads/ltp/LTP_10_2024_release_notes.pdf |access-date=10 December 2024}}</ref>
! colspan=1 | 120 marker proteins based [[Genome Taxonomy Database|GTDB]] 09-RS220<ref name="about">{{cite web |title=GTDB release 09-RS220 |url=https://gtdb.ecogenomic.org/about#4%7C |website=[[Genome Taxonomy Database]] |access-date=10 May 2024}}</ref><ref name="tree">{{cite web |title=bac120_r220.sp_labels |url=https://data.gtdb.ecogenomic.org/releases/release220/220.0/auxillary_files/bac120_r220.sp_labels.tree |website=[[Genome Taxonomy Database]] |access-date=10 May 2024}}</ref><ref name="taxon_history">{{cite web |title=Taxon History |url=https://gtdb.ecogenomic.org/taxon_history/ |website=[[Genome Taxonomy Database]] |access-date=10 May 2024}}</ref>
|- 
| style="vertical-align:top|
{{Clade | style=font-size:90%;line-height:80%
|label1=Root
|1={{clade
  |1={{clade
  |label1="pathogenic"
  |1={{clade
    |1=''[[Bacillus weihenstephanensis]]''
    |2=''[[Bacillus cereus]]''/''[[Bacillus thuringiensis|thuringiensis]]''/''[[Bacillus anthracis|anthracis]]''
     }}
     }}
  |2={{clade
    |1={{clade
    |label1="soil"
    |1={{clade
      |1=''[[Bacillus pumilus]]''
      |2={{clade
        |1=''[[Bacillus subtilis]]''
        |2=''[[Bacillus licheniformis]]''
         }}
       }}
       }}
    |2={{clade
      |1={{clade
      |label1="benthic"
      |1=''[[Geobacillus kaustophilus]]''
         }}
      |2={{clade
        |1={{clade
        |label1="aquatic"
        |1={{clade
          |1={{clade
            |1=''[[Bacillus coahuilensis]]''
            |2=''Bacillus'' sp. m3-13
             }}
          |2=''Bacillus'' sp. NRRLB-14911
           }}
           }}
        |2={{clade
          |label1="benthic"
          |1=''[[Oceanobacillus iheyensis]]''
          |label2="halophiles"
          |2={{clade
            |1=''[[Bacillus halodurans]]''
            |2=''[[Bacillus clausii]]''
             }}
           }}
         }}
       }}
     }}
   }}
}}
|
{{Clade | style=font-size:90%;line-height:80%
|label1=''Bacillus'' s.s.
|1={{clade
  |1={{clade
    |1=''B. capparidis'' <small>Wang et al. 2017</small>
    |2=''B. gobiensis'' <small>Liu et al. 2016</small>
     }}
  |2={{clade
    |1={{clade
      |1={{clade
        |1=''B. changyiensis'' <small>Xiao et al. 2023</small>
        |2=''B. haynesii'' <small>Dunlap et al. 2017</small>
         }}
      |2={{clade
        |1=''B. glycinifermentans'' <small>Kim et al. 2015</small>
        |2={{clade
          |1=''B. paralicheniformis'' <small>Dunlap et al. 2015</small>
          |2={{clade
            |1={{clade
              |1=''[[Bacillus aerius|B. aerius]]'' <small>Shivaji et al. 2006</small>
              |2=''[[Bacillus licheniformis|B. licheniformis]]'' <small>(Weigmann 1898) Chester 1901</small>
               }}
            |2={{clade
              |1=''[[Bacillus sonorensis|B. sonorensis]]'' <small>Palmisano et al. 2001</small>
              |2=''B. swezeyi'' <small>Dunlap et al. 2017</small>
               }}
             }}
           }}
         }}
       }}
    |2={{clade
      |1=''[[Bacillus atrophaeus|B. atrophaeus]]'' <small>Nakamura 1989</small>
      |2={{clade
        |1={{clade
          |1=''[[Bacillus altitudinis|B. altitudinis]]'' <small>Shivaji et al. 2006</small>
          |2={{clade
            |1={{clade
              |1=''[[Bacillus aerophilus|B. aerophilus]]'' <small>Shivaji et al. 2006</small>
              |2=''B. xiamenensis'' <small>Lai, Liu & Shao 2014</small>
               }}
            |2={{clade
              |1=''[[Bacillus safensis|B. safensis]]'' <small>Satomi, La Duc & Venkateswaran 2006</small>
              |2={{clade
                |1=''B. australimaris'' <small>Liu et al. 2016</small>
                |2={{clade
                  |1=''[[Bacillus pumilus|B. pumilus]]'' <small>Meyer & Gottheil 1901</small>
                  |2=''B. zhangzhouensis'' <small>Liu et al. 2016</small>
                   }}
                 }}
               }}
             }}
           }}
        |2={{clade
          |1=''B. velezensis'' <small>Ruiz-Garcia et al. 2005</small>
          |2={{clade
            |1={{clade
              |1=''B. siamensis'' <small>Sumpavapol et al. 2010</small>
              |2=''[[Bacillus amyloliquefaciens|B. amyloliquefaciens]]'' <small>Fukumoto 1943 ex Priest et al. 1987</small>
               }}
            |2={{clade
              |1={{clade
                |1=''[[Bacillus vallismortis|B. vallismortis]]'' <small>Roberts, Nakamura & Cohan 1996</small>
                |2={{clade
                  |1=''B. mexicanus'' <small>de los Santos Villalobos et al. 2023</small>
                  |2=''B. stercoris'' <small>(Adelskov & Patel 2017) Dunlap, Bowman & Zeigler 2020</small>
                   }}
                 }}
              |2={{clade
                |1=''B. spizizenii'' <small>(Nakamura et al. 1999) Dunlap, Bowman & Zeigler 2020</small>
                |2={{clade
                  |1={{clade
                    |1=''B. tequilensis'' <small>Gatson et al. 2006</small>
                    |2={{clade
                      |1=''B. halotolerans'' <small>(Delaporte & Sasson 1967) Tindall 2017</small>
                      |2=''[[Bacillus mojavensis|B. mojavensis]]'' <small>Roberts, Nakamura & Cohan 1994</small>
                       }}
                     }}
                  |2={{clade
                    |1=''B. nakamurai'' <small>Dunlap et al. 2016</small>
                    |2={{clade
                      |1=''B. cabrialesii tritici'' <small>de los Santos-Villalobos et al. 2023</small>
                      |2={{clade
                        |1=''B. cabrialesii'' <small>de los Santos Villalobos et al. 2019</small>
                        |2={{clade
                          |1=''B. inaquosorum'' <small>(Rooney et al. 2009) Dunlap, Bowman & Zeigler 2020</small>
                          |2=''[[Bacillus subtilis|B. subtilis]]'' <small>(Ehrenberg 1835) Cohn 1872</small>
                           }}
                         }}
                       }}
                     }}
                   }}
                 }}
               }}
             }}
           }}
         }}
       }}
     }}
   }}
}}
|
{{Clade | style=font-size:90%;line-height:80%
|label1=''Bacillus'' s.s.
|1={{clade
  |1=''B. gobiensis'' [''B. capparidis'']
  |2={{clade
    |1={{clade
      |1={{clade
        |1=''B. glycinifermentans''
        |2=''[[Bacillus sonorensis|B. sonorensis]]''
         }}
      |2={{clade
        |1=''B. swezeyi''
        |2={{clade
          |1=''[[Bacillus licheniformis|B. licheniformis]]''
          |2={{clade
            |1=''B. haynesii''
            |2=''B. paralicheniformis'' [''B. crescens'' <small>Shivani et al. 2015</small>]
             }}
           }}
         }}
       }}
    |2={{clade
      |1={{clade
        |1={{clade
          |1=''[[Bacillus altitudinis|B. altitudinis]]'' [''[[Bacillus aerius|B. aerius]]''; ''[[Bacillus aerophilus|B. aerophilus]]'']
          |2=''B. xiamenensis''
           }}
        |2={{clade
          |1=''B. zhangzhouensis''
          |2={{clade
            |1=''[[Bacillus pumilus|B. pumilus]]''
            |2={{clade
              |1=''B. australimaris''
              |2=''[[Bacillus safensis|B. safensis]]''
               }}
             }}
           }}
         }}
      |2={{clade
        |1=''[[Bacillus atrophaeus|B. atrophaeus]]''
        |2={{clade
          |1={{clade
            |1=''B. nakamurai''
            |2={{clade
              |1=''[[Bacillus amyloliquefaciens|B. amyloliquefaciens]]''
              |2={{clade
                |1=''B. siamensis''
                |2=''B. velezensis'' [''[[Bacillus lentimorbus|B. lentimorbus]]'' <small>Dutky 1940</small>]
                 }}
               }}
             }}
          |2={{clade
            |1={{clade
              |1=''B. halotolerans''
              |2=''[[Bacillus mojavensis|B. mojavensis]]''
               }}
            |2={{clade
              |1=''B. tequilensis''
              |2={{clade
                |1={{clade
                  |1=''[[Bacillus vallismortis|B. vallismortis]]''
                  |2={{clade
                    |1="''B. rugosus''" <small>Bhattacharya et al. 2020</small>
                    |2=''B. spizizenii''
                     }}
                   }}
                |2={{clade
                  |1=''B. cabrialesii''
                  |2={{clade
                    |1=''B. inaquosorum''
                    |2={{clade
                      |1=''B. stercoris''
                      |2=''[[Bacillus subtilis|B. subtilis]]'' [''Paenibacillus solisilvae'' <small>Kong et al. 2020</small>]
                       }}
                     }}
                   }}
                 }}
               }}
             }}
           }}
         }}
       }}
     }}
   }}
}}
|}

== Species ==
Species orphaned and assigned to other [[genera]]:
{{div col|colwidth=16em}}
* ''[[Bacillus Sohan|B. Symun]]''
* ''[[Bacillus acidicola|B. acidicola]]''
* ''[[Bacillus acidiproducens|B. acidiproducens]]''
* ''[[Bacillus acidocaldarius|B. acidocaldarius]]''
* ''[[Bacillus acidoterrestris|B. acidoterrestris]]''
* ''[[Bacillus aeolius|B. aeolius]]''
* ''[[Bacillus agaradhaerens|B. agaradhaerens]]''
* ''[[Bacillus agri|B. agri]]''
* ''[[Bacillus aidingensis|B. aidingensis]]''
* ''[[Bacillus akibai|B. akibai]]''
* ''[[Bacillus albus|B. albus]]''
* ''[[Bacillus alcalophilus|B. alcalophlus]]''
* ''[[Bacillus Sohan|B. algicola]]''
* ''[[Bacillus alginolyticus|B. alginolyticus]]''
* ''[[Bacillus alkalidiazotrophicus|B. alkalidiazotrophicus]]''
* ''[[Bacillus alkalinitrilicus|B. alkalinitrilicus]]''
* ''[[Bacillus alkalisediminis|B. alkalisediminis]]''
* ''[[Bacillus alkalitelluris|B. alkalitelluris]]''
* ''[[Bacillus alveayuensis|B. alveayuensis]]''
* ''[[Bacillus alvei|B. alvei]]''
* ''[[Bacillus aminovorans|B. aminovorans]]''<ref>{{cite journal | vauthors = Loshon CA, Beary KE, Gouveia K, Grey EZ, Santiago-Lara LM, Setlow P | title = Nucleotide sequence of the sspE genes coding for gamma-type small, acid-soluble spore proteins from the round-spore-forming bacteria Bacillus aminovorans, Sporosarcina halophila and S. ureae | journal = Biochimica et Biophysica Acta (BBA) - Gene Structure and Expression | volume = 1396 | issue = 2 | pages = 148–152 | date = March 1998 | pmid = 9540829 | doi = 10.1016/S0167-4781(97)00204-2 }}</ref>
* ''[[Bacillus amylolyticus|B. amylolyticus]]''
* ''[[Bacillus andreesenii|B. andreesenii]]''
* ''[[Bacillus aneurinilyticus|B. aneurinilyticus]]''
* ''[[Bacillus anthracis|B. anthracis]]''
* ''[[Bacillus aquimaris|B. aquimaris]]''
* ''[[Bacillus arenosi|B. arenosi]]''
* ''[[Bacillus arseniciselenatis|B. arseniciselenatis]]''
* ''[[Bacillus arsenicus|B. arsenicus]]''
* ''[[Bacillus aurantiacus|B. aurantiacus]]''
* ''[[Bacillus arvi|B. arvi]]''
* ''[[Bacillus aryabhattai|B. aryabhattai]]''
* ''[[Bacillus asahii|B. asahii]]''
* ''[[Bacillus axarquiensis|B. axarquiensis]]''
* ''[[Bacillus azotofixans|B. azotofixans]]''
* ''[[Bacillus azotoformans|B. azotoformans]]''
* ''[[Bacillus badius|B. badius]]''
* ''[[Bacillus barbaricus|B. barbaricus]]''
* ''[[Bacillus bataviensis|B. bataviensis]]''
* ''[[Bacillus beijingensis|B. beijingensis]]''
* ''[[Bacillus benzoevorans|B. benzoevorans]]''
* ''[[Bacillus beringensis|B. beringensis]]''
* ''[[Bacillus berkeleyi|B. berkeleyi]]''
* ''[[Bacillus beveridgei|B. beveridgei]]''
* ''[[Bacillus bogoriensis|B. bogoriensis]]''
* ''[[Bacillus boroniphilus|B. boroniphilus]]''
* ''[[Bacillus borstelensis|B. borstelensis]]''
* ''[[Bacillus brevis|B. brevis]]''
* ''[[Bacillus butanolivorans|B. butanolivorans]]''
* ''[[Bacillus canaveralius|B. canaveralius]]''
* ''[[Bacillus carboniphilus|B. carboniphilus]]''
* ''[[Bacillus cecembensis|B. cecembensis]]''
* ''[[Bacillus cellulosilyticus|B. cellulosilyticus]]''
* ''[[Bacillus centrosporus|B. centrosporus]]''
* ''[[Bacillus cereus|B. cereus]]''
* ''[[Bacillus chagannorensis|B. chagannorensis]]''
* ''[[Bacillus chitinolyticus|B. chitinolyticus]]''
* ''[[Bacillus chondroitinus|B. chondroitinus]]''
* ''[[Bacillus choshinensis|B. choshinensis]]''
* ''[[Bacillus chungangensis|B. chungangensis]]''
* ''[[Bacillus cibi|B. cibi]]''
* ''[[Bacillus circulans|B. circulans]]''
* ''[[Bacillus clarkii|B. clarkii]]''
* ''[[Bacillus clausii|B. clausii]]''
* ''[[Bacillus coagulans|B. coagulans]]''
* ''[[Bacillus coahuilensis|B. coahuilensis]]''
* ''[[Bacillus cohnii|B. cohnii]]''
* ''[[Bacillus composti|B. composti]]''
* ''[[Bacillus curdlanolyticus|B. curdlanolyticus]]''
* ''[[Bacillus cycloheptanicus|B. cycloheptanicus]]''
* ''[[Bacillus cytotoxicus|B. cytotoxicus]]''
* ''[[Bacillus daliensis|B. daliensis]]''
* ''[[Bacillus decisifrondis|B. decisifrondis]]''
* ''[[Bacillus decolorationis|B. decolorationis]]''
* ''[[Bacillus deserti|B. deserti]]''
* ''[[Bacillus dipsosauri|B. dipsosauri]]''
* ''[[Bacillus drentensis|B. drentensis]]''
* ''[[Bacillus edaphicus|B. edaphicus]]''
* ''[[Bacillus ehimensis|B. ehimensis]]''
* ''[[Bacillus eiseniae|B. eiseniae]]''
* ''[[Bacillus enclensis|B. enclensis]]''
* ''[[Bacillus endophyticus|B. endophyticus]]''
* ''[[Bacillus endoradicis|B. endoradicis]]''
* ''[[Bacillus farraginis|B. farraginis]]''
* ''[[Bacillus fastidiosus|B. fastidiosus]]''
* ''[[Bacillus fengqiuensis|B. fengqiuensis]]''
* ''[[Bacillus filobacterium rodentium|B. filobacterium rodentuim]]''
* ''[[Bacillus firmus|B. firmus]]''
* ''[[Bacillus flexus|B. flexus]]''
* ''[[Bacillus foraminis|B. foraminis]]''
* ''[[Bacillus fordii|B. fordii]]''
* ''[[Bacillus formosus|B. formosus]]''
* ''[[Bacillus fortis|B. fortis]]''
* ''[[Bacillus fumarioli|B. fumarioli]]''
* ''[[Bacillus funiculus|B. funiculus]]''
* ''[[Bacillus fusiformis|B. fusiformis]]''
* ''[[Bacillus gaemokensis|B. gaemokensis]]''
* ''[[Bacillus galactophilus|B. galactophilus]]''
* ''[[Bacillus galactosidilyticus|B. galactosidilyticus]]''
* ''[[Bacillus galliciensis|B. galliciensis]]''
* ''[[Bacillus gelatini|B. gelatini]]''
* ''[[Bacillus gibsonii|B. gibsonii]]''
* ''[[Bacillus ginsengi|B. ginsengi]]''
* ''[[Bacillus ginsengihumi|B. ginsengihumi]]''
* ''[[Bacillus ginsengisoli|B. ginsengisoli]]''
* ''[[Bacillus glucanolyticus|B. glucanolyticus]]''
* ''[[Bacillus gordonae|B. gordonae]]''
* ''[[Bacillus gottheilii|B. gottheilii]]''
* ''[[Bacillus graminis|B. graminis]]''
* ''[[Bacillus halmapalus|B. halmapalus]]''
* ''[[Bacillus haloalkaliphilus|B. haloalkaliphilus]]''
* ''[[Bacillus halochares|B. halochares]]''
* ''[[Bacillus halodenitrificans|B. halodenitrificans]]''
* ''[[Bacillus halodurans|B. halodurans]]''
* ''[[Bacillus halophilus|B. halophilus]]''
* ''[[Bacillus halosaccharovorans|B. halosaccharovorans]]''
* ''[[Bacillus hemicellulosilyticus|B. hemicellulosilyticus]]''
* ''[[Bacillus hemicentroti|B. hemicentroti]]''
* ''[[Bacillus herbersteinensis|B. herbersteinensis]]''
* ''[[Bacillus horikoshii|B. horikoshii]]''
* ''[[Bacillus horneckiae|B. horneckiae]]''
* ''[[Bacillus horti|B. horti]]''
* ''[[Bacillus huizhouensis|B. huizhouensis]]''
* ''[[Bacillus humi|B. humi]]''
* ''[[Bacillus hwajinpoensis|B. hwajinpoensis]]''
* ''[[Bacillus idriensis|B. idriensis]]''
* ''[[Bacillus indicus|B. indicus]]''
* ''[[Bacillus infantis|B. infantis]]''
* ''[[Bacillus infernus|B. infernus]]''
* ''[[Bacillus insolitus|B. insolitus]]''
* ''[[Bacillus invictae|B. invictae]]''
* ''[[Bacillus iranensis|B. iranensis]]''
* ''[[Bacillus isabeliae|B. isabeliae]]''
* ''[[Bacillus isronensis|B. isronensis]]''
* ''[[Bacillus jeotgali|B. jeotgali]]''
* ''[[Bacillus kaustophilus|B. kaustophilus]]''
* ''[[Bacillus kobensis|B. kobensis]]''
* ''[[Bacillus kochii|B. kochii]]''
* ''[[Bacillus kokeshiiformis|B. kokeshiiformis]]''
* ''[[Bacillus koreensis|B. koreensis]]''
* ''[[Bacillus korlensis|B. korlensis]]''
* ''[[Bacillus kribbensis|B. kribbensis]]''
* ''[[Bacillus krulwichiae|B. krulwichiae]]''
* ''[[Bacillus laevolacticus|B. laevolacticus]]''
* ''[[Bacillus larvae|B. larvae]]''
* ''[[Bacillus laterosporus|B. laterosporus]]''
* ''[[Bacillus lautus|B. lautus]]''
* ''[[Bacillus lehensis|B. lehensis]]''
* ''[[Bacillus lentus|B. lentus]]''
* ''[[Bacillus ligniniphilus|B. ligniniphilus]]''
* ''[[Bacillus litoralis|B. litoralis]]''
* ''[[Bacillus locisalis|B. locisalis]]''
* ''[[Bacillus luciferensis|B. luciferensis]]''
* ''[[Bacillus luteolus|B. luteolus]]''
* ''[[Bacillus luteus|B. luteus]]''
* ''[[Bacillus macauensis|B. macauensis]]''
* ''[[Bacillus macerans|B. macerans]]''
* ''[[Bacillus macquariensis|B. macquariensis]]''
* ''[[Bacillus macyae|B. macyae]]''
* ''[[Bacillus malacitensis|B. malacitensis]]''
* ''[[Bacillus mannanilyticus|B. mannanilyticus]]''
* ''[[Bacillus marisflavi|B. marisflavi]]''
* ''[[Bacillus marismortui|B. marismortui]]''
* ''[[Bacillus marmarensis|B. marmarensis]]''
* ''[[Bacillus massiliensis|B. massiliensis]]''
* ''[[Bacillus megaterium|B. megaterium]]''
* "''[[Bacillus mesentericus|B. mesentericus]]''"
* ''[[Bacillus mesonae|B. mesonae]]''
* ''[[Bacillus methanolicus|B. methanolicus]]''
* ''[[Bacillus methylotrophicus|B. methylotrophicus]]''
* ''[[Bacillus migulanus|B. migulanus]]''
* ''[[Bacillus mucilaginosus|B. mucilaginosus]]''
* ''[[Bacillus muralis|B. muralis]]''
* ''[[Bacillus murimartini|B. murimartini]]''
* ''[[Bacillus mycoides|B. mycoides]]''
* ''[[Bacillus naganoensis|B. naganoensis]]''
* ''[[Bacillus nanhaiensis|B. nanhaiensis]]''
* ''[[Bacillus nanhaiisediminis|B. nanhaiisediminis]]''
* ''[[Bacillus nealsonii|B. nealsonii]]''
* ''[[Bacillus neidei|B. neidei]]''
* ''[[Bacillus neizhouensis|B. neizhouensis]]''
* ''[[Bacillus niabensis|B. niabensis]]''
* ''[[Bacillus niacini|B. niacini]]''
* ''[[Bacillus novalis|B. novalis]]''
* ''[[Bacillus oceanisediminis|B. oceanisediminis]]''
* ''[[Bacillus odysseyi|B. odysseyi]]''
* ''[[Bacillus okhensis|B. okhensis]]''
* ''[[Bacillus okuhidensis|B. okuhidensis]]''
* ''[[Bacillus oleronius|B. oleronius]]''
* ''[[Bacillus oryzaecorticis|B. oryzaecorticis]]''
* ''[[Bacillus oshimensis|B. oshimensis]]''
* ''[[Bacillus pabuli|B. pabuli]]''
* ''[[Bacillus pakistanensis|B. pakistanensis]]''
* ''[[Bacillus pallidus|B. pallidus]]''
* ''[[Bacillus pallidus|B. pallidus]]''
* ''[[Bacillus panacisoli|B. panacisoli]]''
* ''[[Bacillus panaciterrae|B. panaciterrae]]''
* ''[[Bacillus pantothenticus|B. pantothenticus]]''
* ''[[Bacillus parabrevis|B. parabrevis]]''
* ''[[Bacillus paraflexus|B. paraflexus]]''
* ''[[Bacillus pasteurii|B. pasteurii]]''
* ''[[Bacillus patagoniensis|B. patagoniensis]]''
* ''[[Bacillus peoriae|B. peoriae]]''
* ''[[Bacillus persepolensis|B. persepolensis]]''
* ''[[Bacillus persicus|B. persicus]]''
* ''[[Bacillus pervagus|B. pervagus]]''
* ''[[Bacillus plakortidis|B. plakortidis]]''
* ''[[Bacillus pocheonensis|B. pocheonensis]]''
* ''[[Bacillus polygoni|B. polygoni]]''
* ''[[Bacillus polymyxa|B. polymyxa]]''
* ''[[Bacillus popilliae|B. popilliae]]''
* ''[[Bacillus pseudalcalophilus|B. pseudalcalophilus]]''
* ''[[Bacillus pseudofirmus|B. pseudofirmus]]''
* ''[[Bacillus pseudomycoides|B. pseudomycoides]]''
* ''[[Bacillus psychrodurans|B. psychrodurans]]''
* ''[[Bacillus psychrophilus|B. psychrophilus]]''
* ''[[Bacillus psychrosaccharolyticus|B. psychrosaccharolyticus]]''
* ''[[Bacillus psychrotolerans|B. psychrotolerans]]''
* ''[[Bacillus pulvifaciens|B. pulvifaciens]]''
* ''[[Bacillus purgationiresistens|B. purgationiresistens]]''
* ''[[Bacillus pycnus|B. pycnus]]''
* ''[[Bacillus qingdaonensis|B. qingdaonensis]]''
* ''[[Bacillus qingshengii|B. qingshengii]]''
* ''[[Bacillus reuszeri|B. reuszeri]]''
* ''[[Bacillus rhizosphaerae|B. rhizosphaerae]]''
* ''[[Bacillus rigui|B. rigui]]''
* ''[[Bacillus ruris|B. ruris]]''
* ''[[Bacillus salarius|B. salarius]]''
* ''[[Bacillus salexigens|B. salexigens]]''
* ''[[Bacillus saliphilus|B. saliphilus]]''
* ''[[Bacillus schlegelii|B. schlegelii]]''
* ''[[Bacillus sediminis|B. sediminis]]''
* ''[[Bacillus selenatarsenatis|B. selenatarsenatis]]''
* ''[[Bacillus selenitireducens|B. selenitireducens]]''
* ''[[Bacillus seohaeanensis|B. seohaeanensis]]''
* ''[[Bacillus shacheensis|B. shacheensis]]''
* ''[[Bacillus shackletonii|B. shackletonii]]''
* ''[[Bacillus silvestris|B. silvestris]]''
* ''[[Bacillus simplex|B. simplex]]''
* ''[[Bacillus siralis|B. siralis]]''
* ''[[Bacillus smithii|B. smithii]]''
* ''[[Bacillus soli|B. soli]]''
* ''[[Bacillus solimangrovi|B. solimangrovi]]''
* ''[[Bacillus solisalsi|B. solisalsi]]''
* ''[[Bacillus songklensis|B. songklensis]]''
* ''[[Bacillus sphaericus|B. sphaericus]]''
* ''[[Bacillus sporothermodurans|B. sporothermodurans]]''
* ''[[Bacillus stearothermophilus|B. stearothermophilus]]''
* ''[[Bacillus stratosphericus|B. stratosphericus]]''
* ''[[Bacillus subterraneus|B. subterraneus]]''
* ''[[Bacillus taeanensis|B. taeanensis]]''
* ''[[Bacillus thermantarcticus|B. thermantarcticus]]''
* ''[[Bacillus thermoaerophilus|B. thermoaerophilus]]''
* ''[[Bacillus thermoamylovorans|B. thermoamylovorans]]''
* ''[[Bacillus thermocatenulatus|B. thermocatenulatus]]''
* ''[[Bacillus thermocloacae|B. thermocloacae]]''
* ''[[Bacillus thermocopriae|B. thermocopriae]]''
* ''[[Bacillus thermodenitrificans|B. thermodenitrificans]]''
* ''[[Bacillus thermoglucosidasius|B. thermoglucosidasius]]''
* ''[[Bacillus thermolactis|B. thermolactis]]''
* ''[[Bacillus thermoleovorans|B. thermoleovorans]]''
* ''[[Bacillus thermophilus|B. thermophilus]]''
* ''[[Bacillus thermoproteolyticus|B. thermoproteolyticus]]''
* ''[[Bacillus thermoruber|B. thermoruber]]''
* ''[[Bacillus thermosphaericus|B. thermosphaericus]]''
* ''[[Bacillus thiaminolyticus|B. thiaminolyticus]]''
* ''[[Bacillus thioparans|B. thioparans]]''
* ''[[Bacillus thuringiensis|B. thuringiensis]]''
* ''[[Bacillus tianshenii|B. tianshenii]]''
* ''[[Bacillus toyonensis|B. toyonensis]]''
* ''[[Bacillus trypoxylicola|B. trypoxylicola]]''
* ''[[Bacillus tusciae|B. tusciae]]''
* ''[[Bacillus validus|B. validus]]''
* ''[[Bacillus vedderi|B. vedderi]]''
* ''[[Bacillus vietnamensis|B. vietnamensis]]''
* ''[[Bacillus vireti|B. vireti]]''
* ''[[Bacillus vulcani|B. vulcani]]''
* ''[[Bacillus wakoensis|B. wakoensis]]''
* ''[[Bacillus xiaoxiensis|B. xiaoxiensis]]''
* ''[[Bacillus zanthoxyli|B. zanthoxyli]]''
* ''[[Bacillus zhanjiangensis|B. zhanjiangensis]]{{div col end}}

== Ecological and clinical significance ==
''Bacillus'' species are ubiquitous in nature, e.g. in soil. They can occur in extreme environments such as high pH (''[[Bacillus alcalophilus|B. alcalophilus]]''), high temperature (''[[Bacillus thermophilus|B. thermophilus]]''), and high salt concentrations (''[[Bacillus halodurans|B. halodurans]]''). They also are very commonly found as [[endophyte]]s in plants where they can play a critical role in their [[immune system]], [[Plant nutrition|nutrient absorption]] and [[Nitrogen Fixation|nitrogen fixing]] capabilities.<ref>{{cite journal | vauthors = Ding Y, Wang J, Liu Y, Chen S | date = 2005 | title = Isolation and identification of nitrogen-fixing bacilli from plant rhizospheres in Beijing region | journal = Journal of Applied Microbiology | volume = 99 | issue = 5 | pages = 1271–1281 | doi = 10.1111/j.1365-2672.2005.02738.x| pmid = 16238759 | s2cid = 19917931 }}</ref><ref>{{cite journal | vauthors = Xie G, Su B, Cui Z | title = Isolation and identification of N2-fixing strains of Bacillus in rice rhizosphere of the Yangtze River Valley | journal = Wei Sheng Wu Xue Bao = Acta Microbiologica Sinica | publisher = Chinese Academy of Sciences | volume = 38 | issue = 6 | pages = 480–483 | language = Chinese | date = Dec 1998 | url = https://europepmc.org/article/MED/12548929 | pmid = 12548929}}</ref><ref>{{cite journal | vauthors = War Nongkhla F, Joshi S | date = 2014 | title = Epiphytic and endophytic bacteria that promote growth of ethnomedicinal plants in the subtropical forests of Meghalaya, India | journal = Revista de Biología Tropical | volume = 62 | issue = 4 | pages = 1295–1308 | doi = 10.15517/rbt.v62i4.12138| pmid = 25720168 | doi-access = free }}</ref><ref>{{cite journal | vauthors = Jooste M, Roets F, Midgley GF et al | title = Nitrogen-fixing bacteria and Oxalis – evidence for a vertically inherited bacterial symbiosis | journal = BMC Plant Biology | volume = 19 | page = 441 | date = 2019 | issue = 1 | doi = 10.1186/s12870-019-2049-7| pmid = 31646970 | pmc = 6806586 | doi-access = free }}</ref><ref>{{cite journal | vauthors = Ramesh A, Sharma SK, Sharma MP, Yadav N, Joshi OP | title = Inoculation of zinc solubilizing Bacillus aryabhattai strains for improved growth, mobilization and biofortification of zinc in soybean and wheat cultivated in Vertisols of central India | journal = Applied Soil Ecology | volume = 73 | date = 2014 | pages = 87–96 | issn = 0929-1393 | doi = 10.1016/j.apsoil.2013.08.009| bibcode = 2014AppSE..73...87R }}</ref> ''[[Bacillus thuringiensis|B. thuringiensis]]'' produces a toxin that can kill insects and thus has been used as [[insecticide]].<ref>{{cite book | vauthors = Slonczewski JL, Foster JW | date = 2011 | title = Microbiology: An Evolving Science | edition = 2nd | publisher = Norton }}</ref> ''B. siamensis'' has antimicrobial compounds that inhibit plant pathogens, such as the fungi ''[[Rhizoctonia solani]]'' and ''[[Botrytis cinerea]]'', and they promote plant growth by volatile emissions.<ref>{{cite journal | vauthors = Jeong H, Jeong DE, Kim SH, Song GC, Park SY, Ryu CM, Park SH, Choi SK | title = Draft genome sequence of the plant growth-promoting bacterium Bacillus siamensis KCTC 13613T | journal = Journal of Bacteriology | volume = 194 | issue = 15 | pages = 4148–4149 | date = August 2012 | pmid = 22815459 | pmc = 3416560 | doi = 10.1128/JB.00805-12 }}</ref> Some species of ''Bacillus'' are naturally [[natural competence|competent]] for DNA uptake by [[transformation (genetics)|transformation]].<ref>{{cite journal | vauthors = Keen EC, Bliskovsky VV, Adhya SL, Dantas G | title = Draft Genome Sequence of the Naturally Competent ''Bacillus simplex'' Strain WY10 | journal = Genome Announcements | volume = 5 | issue = 46 | pages = e01295–17 | date = November 2017 | pmid = 29146837 | pmc = 5690344 | doi = 10.1128/genomeA.01295-17 }}
</ref>
* Two ''Bacillus'' species are medically significant: ''[[Bacillus anthracis|B. anthracis]]'', which causes [[anthrax]]; and ''[[Bacillus cereus|B. cereus]]'', which causes [[foodborne illness|food poisoning]], with symptoms similar to that caused by ''[[Staphylococcus]]''.<ref name=Sherris>{{cite book | veditors = Ryan KJ, Ray CG | title = Sherris Medical Microbiology | edition = 4th | publisher = McGraw Hill | year = 2004 | isbn = 978-0-8385-8529-0 }}</ref>
** ''B. cereus'' produces toxins which cause two different set of symptoms:
*** emetic toxin which can cause vomiting and nausea
*** diarrhea
* ''[[B. thuringiensis]]'' is an important [[insect]] pathogen, and is sometimes used to control insect pests.
* ''B. subtilis'' is an important [[model organism]]. It is also a notable food spoiler, causing ropiness in bread and related food.
** ''B. subtilis'' can also produce and secrete antibiotics.
* Some environmental and commercial strains of ''[[Bacillus coagulans|B. coagulans]]'' may play a role in food spoilage of highly acidic, tomato-based products.

==Industrial significance==
Many ''Bacillus'' species are able to [[secretion|secrete]] large quantities of enzymes. ''[[Bacillus amyloliquefaciens]]'' is the source of a natural antibiotic protein [[barnase]] (a [[ribonuclease]]), [[alpha amylase]] used in starch hydrolysis, the [[protease]] [[subtilisin]] used with detergents, and the [[BamH1]] [[restriction enzyme]] used in DNA research.{{citation needed|date=February 2023}}

A portion of the ''[[Bacillus thuringiensis]]'' genome was incorporated into [[Genetically modified maize#Bt corn|corn]]<ref>{{cite web |url=http://www.bt.ucsd.edu/bt_history.html |title=History of Bt |publisher=University of California San Diego |access-date=28 June 2024}}</ref> and [[Bt cotton|cotton]]<ref name="James 1996">{{cite web|last=James|first=Clive|title=Global Review of the Field Testing and Commercialization of Transgenic Plants: 1986 to 1995|url=https://www.isaaa.org/resources/publications/briefs/01/download/isaaa-brief-01-1996.pdf|publisher=The International Service for the Acquisition of Agri-biotech Applications|access-date=17 July 2010|year=1996}}</ref> crops. The resulting plants are resistant to some insect pests.<ref>{{cite web| vauthors = Peairs FB |publisher=Colorado State University Extension Office|year= 2013|url=http://extension.colostate.edu/docs/pubs/crops/00707.pdf |archive-url=https://ghostarchive.org/archive/20221009/http://extension.colostate.edu/docs/pubs/crops/00707.pdf |archive-date=2022-10-09 |url-status=live|title=Bt Corn: Health and the Environment – 0.707}}</ref>

''[[Bacillus subtilis]]'' ([[Nattō|natto]]) is the key microbial participant in the ongoing production of the soya-based traditional natto fermentation, and some ''Bacillus'' species are on the Food and Drug Administration's GRAS (generally regarded as safe) list.<ref>{{Cite journal |last=Schallmey |first=Marcus |last2=Singh |first2=Ajay |last3=Ward |first3=Owen P |date=2004-01-01 |title=Developments in the use of Bacillus species for industrial production |url=https://cdnsciencepub.com/doi/10.1139/w03-076 |journal=Canadian Journal of Microbiology |volume=50 |issue=1 |pages=1–17 |doi=10.1139/w03-076 |issn=0008-4166}}</ref>

The capacity of selected ''Bacillus'' strains to produce and secrete large quantities (20–25 g/L) of extracellular enzymes has placed them among the most important industrial enzyme producers.{{citation needed|date=February 2023}} The ability of different species to ferment in the acid, neutral, and alkaline pH ranges, combined with the presence of thermophiles in the genus, has led to the development of a variety of new commercial enzyme products with the desired temperature, pH activity, and stability properties to address a variety of specific applications. Classical mutation and (or) selection techniques, together with advanced cloning and protein engineering strategies, have been exploited to develop these products.{{citation needed|date=February 2023}}

Efforts to produce and secrete high yields of foreign recombinant proteins in ''Bacillus'' hosts initially appeared to be hampered by the degradation of the products by the host proteases.{{citation needed|date=February 2023}} Recent studies have revealed that the slow folding of heterologous proteins at the membrane-cell wall interface of Gram-positive bacteria renders them vulnerable to attack by wall-associated proteases.{{citation needed|date=February 2023}} In addition, the presence of thiol-disulphide oxidoreductases in ''B. subtilis'' may be beneficial in the secretion of disulphide-bond-containing proteins. Such developments from our understanding of the complex protein translocation machinery of Gram-positive bacteria should allow the resolution of current secretion challenges and make ''Bacillus'' species preeminent hosts for heterologous protein production.{{citation needed|date=February 2023}}

''Bacillus'' strains have also been developed and engineered as industrial producers of nucleotides, the vitamin riboflavin, the flavor agent ribose, and the supplement poly-gamma-glutamic acid. With the recent characterization of the genome of ''B. subtilis'' 168 and of some related strains, ''Bacillus'' species are poised to become the preferred hosts for the production of many new and improved products as we move through the genomic and proteomic era.<ref>{{cite journal | vauthors = Schallmey M, Singh A, Ward OP | title = Developments in the use of Bacillus species for industrial production | journal = Canadian Journal of Microbiology | volume = 50 | issue = 1 | pages = 1–17 | date = January 2004 | pmid = 15052317 | doi = 10.1139/w03-076 }}</ref>

==Use as model organism==
[[File:Bacillus subtilis colonies.jpg|thumb|left|Colonies of the model species ''[[Bacillus subtilis]]'' on an agar plate]]
''[[Bacillus subtilis]]'' is one of the best understood prokaryotes, in terms of molecular and cellular biology. Its superb genetic amenability and relatively large size have provided the powerful tools required to investigate a bacterium from all possible aspects. Recent improvements in [[fluorescent microscopy]] techniques have provided novel insight into the dynamic structure of a single cell organism. Research on ''B. subtilis'' has been at the forefront of bacterial molecular biology and cytology, and the organism is a model for differentiation, gene/protein regulation, and cell cycle events in bacteria.<ref name=Graumann>{{cite book | veditors = Graumann P | title = Bacillus: Cellular and Molecular Biology | edition = 2nd | publisher = Caister Academic Press | year = 2012 | url=http://www.horizonpress.com/bacillus | id = [http://www.horizonpress.com/bacillus ] | isbn = 978-1-904455-97-4}}</ref>
{{clear}}

== See also ==
* [[List of Bacteria genera]]
* [[List of bacterial orders]]
* ''[[Paenibacillus]]'' and ''[[Virgibacillus]]'', genera of bacteria formerly included in ''Bacillus''.<ref>{{cite journal | vauthors = Ash C, Priest FG, Collins MD | title = Molecular identification of rRNA group 3 bacilli (Ash, Farrow, Wallbanks and Collins) using a PCR probe test. Proposal for the creation of a new genus Paenibacillus | journal = Antonie van Leeuwenhoek | volume = 64 | issue = 3–4 | pages = 253–260 | date = 1994 | pmid = 8085788 | doi = 10.1007/BF00873085 | s2cid = 7391845 }}</ref><ref>{{cite journal| vauthors = Heyndrickx M, Lebbe L, Kersters K, De Vos P, Forsyth G, Logan NA |title=Virgibacillus: a new genus to accommodate Bacillus pantothenticus (Proom and Knight 1950). Emended description of Virgibacillus pantothenticus |journal=International Journal of Systematic Bacteriology |date= January 1998 |volume=48 |issue=1 |pages=99–106 |doi=10.1099/00207713-48-1-99 |doi-access=free}}</ref>

== References ==
{{Reflist}}

== External links ==
{{Commons category|Bacillus}}
* [https://patricbrc.org/view/Taxonomy/1386#view_tab=overview Bacillus] genomes and related information at [http://patricbrc.org/ PATRIC], a Bioinformatics Resource Center funded by [https://www.niaid.nih.gov/ NIAID]

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{{Gram-positive firmicutes diseases}}
{{Taxonbar|from=Q212032}}
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[[Category:Bacillus| ]]
[[Category:Bacteria genera]]
[[Category:Gram-positive bacteria]]