Editing Enzyme (section)

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Enzyme production ([[Transcription (genetics)|transcription]] and [[Translation (genetics)|translation]] of enzyme genes) can be enhanced or diminished by a cell in response to changes in the cell's environment. This form of [[regulation of gene expression|gene regulation]] is called [[enzyme induction]]. For example, bacteria may become [[antibiotic resistance|resistant to antibiotics]] such as [[penicillin]] because enzymes called [[beta-lactamase]]s are induced that hydrolyse the crucial [[Beta-lactam|beta-lactam ring]] within the penicillin molecule.<ref name="pmid8452343">{{cite journal | vauthors = Bennett PM, Chopra I | title = Molecular basis of beta-lactamase induction in bacteria | journal = Antimicrobial Agents and Chemotherapy | volume = 37 | issue = 2 | pages = 153–158 | date = February 1993 | pmid = 8452343 | pmc = 187630 | doi = 10.1128/aac.37.2.153 }}</ref> Another example comes from enzymes in the [[liver]] called [[cytochrome P450 oxidase]]s, which are important in [[drug metabolism]]. Induction or inhibition of these enzymes can cause [[drug interaction]]s.<ref name = "Skett_Gibson_2001">{{cite book |vauthors=Skett P, Gibson GG | title = Introduction to Drug Metabolism | date = 2001 | publisher = Nelson Thornes Publishers | location = Cheltenham, UK | isbn = 978-0748760114 | pages = 87–118 | edition = 3 | chapter = Chapter 3: Induction and Inhibition of Drug Metabolism }}</ref> Enzyme levels can also be regulated by changing the rate of enzyme [[catabolism|degradation]].<ref name="Stryer_2002" />{{rp|30.1.1}} The opposite of enzyme induction is [[enzyme repression]].