Editing Membrane protein (section)

===Peripheral membrane proteins===
[[File:Monotopic membrane protein.svg|thumb|right|400px|Schematic representation of the different types of interaction between monotopic membrane proteins and the [[cell membrane]]: 1. interaction by an [[amphipathic]] [[α-helix]] parallel to the membrane plane (in-plane membrane helix)  2. interaction by a [[Hydrophobe|hydrophobic]] loop  3. interaction by a covalently bound [[membrane lipid]] (''[[lipidation]]'')  4. electrostatic or [[Intermolecular forces#Ionic interactions|ionic interactions]] with membrane lipids (''e.g.'' through a [[calcium ion]])]]

{{Main|Peripheral membrane protein}}
[[Peripheral membrane protein]]s are temporarily attached either to the [[lipid bilayer]] or to integral proteins by a combination of [[hydrophobic]], [[electrostatic]], and other non-covalent interactions. Peripheral proteins dissociate following treatment with a polar reagent, such as a solution with an elevated [[pH]] or high salt concentrations.{{cn|date=June 2023}}

Integral and peripheral proteins may be post-translationally modified, with added [[fatty acid]], [[diacylglycerol]]<ref name="pmid29695868">{{cite journal | vauthors = Sun C, Benlekbir S, Venkatakrishnan P, Wang Y, Hong S, Hosler J, Tajkhorshid E, Rubinstein JL, Gennis RB | title = Structure of the alternative complex III in a supercomplex with cytochrome oxidase | journal = Nature | volume = 557 | issue = 7703 | pages = 123–126 | date = May 2018 | pmid = 29695868 | pmc = 6004266 | doi = 10.1038/s41586-018-0061-y | bibcode = 2018Natur.557..123S }}</ref> or [[prenyl]] chains, or [[Glycophosphatidylinositol|GPI]] (glycosylphosphatidylinositol), which may be anchored in the lipid bilayer.