Editing Exoenzyme (section)

{{Short description|Enzyme that functions outside the cell it is secreted from}}
[[File:Organelles of the Secretory Pathway.png|thumb|upright=1.5|Organelles of the secretory pathway involved in the secretion of exoenzymes]]

An '''exoenzyme''', or '''extracellular enzyme''', is an [[enzyme]] that is secreted by a [[cell (biology)|cell]] and functions [[extracellular|outside that cell]]. Exoenzymes are produced by both [[prokaryotic]] and [[eukaryotic]] cells and have been shown to be a crucial component of many [[biological process]]es. Most often these enzymes are involved in the breakdown of larger [[macromolecule]]s. The breakdown of these larger macromolecules is critical for allowing their constituents to pass through the [[cell membrane]] and enter into the cell. For [[human]]s and other complex organisms, this process is best characterized by the [[digestive system]] which breaks down solid [[nutrients|food]]<ref>{{cite journal |vauthors= Kong F, Singh RP |title= Disintegration of solid foods in human stomach |journal= Journal of Food Science |volume= 73 |issue= 5 |pages= R67–80 |date= June 2008 |pmid= 18577009 |doi= 10.1111/j.1750-3841.2008.00766.x|doi-access= free }}</ref> via exoenzymes. The small molecules, generated by the exoenzyme activity, enter into cells and are utilized for various cellular functions. [[Bacteria]] and [[fungi]] also produce exoenzymes to [[digestion|digest]] [[nutrient]]s in their [[environment (biophysical)|environment]], and these organisms can be used to conduct laboratory [[assay]]s to identify the presence and function of such exoenzymes.<ref name=assays/> Some [[pathogenic]] species also use exoenzymes as [[virulence factor]]s to assist in the spread of these [[pathogen|disease-causing]] [[microorganism]]s.<ref name=virulence/> In addition to the integral roles in biological systems, different classes of [[microorganism|microbial]] exoenzymes have been used by humans since [[prehistory|pre-historic times]] for such diverse purposes as [[food processing|food production]], [[biofuel]]s, [[textile manufacturing|textile production]] and in the [[pulp and paper industry|paper industry]].<ref name=geobiology>{{cite book |last=Thiel|first=ed. by Joachim Reitner, Volker|title=Encyclopedia of geobiology|publisher=Springer|location=Dordrecht|isbn=9781402092121|pages=355–359}}</ref> Another important role that microbial exoenzymes serve is in the natural ecology and [[bioremediation]] of [[ecoregion#Terrestrial|terrestrial]] and [[ecoregion#Marine|marine]]<ref>{{cite journal |vauthors= Arnosti C |title= Microbial extracellular enzymes and the marine carbon cycle |journal= Annual Review of Marine Science |volume= 3 |issue= 1 |pages= 401–25 |date= 15 January 2011 |pmid= 21329211 |doi= 10.1146/annurev-marine-120709-142731|bibcode= 2011ARMS....3..401A }}</ref> environments.