View source for Microcin

{{Short description|Class of very small bacterially produced peptide antibiotics}}
{{missing information|Microcin B17 and sagBCD family|date=December 2020}}
{{Infobox protein family
| Symbol = Subtilosin_A
| Name = Subtilosin_A
| image = PDB 1pxq EBI.jpg
| width =
| caption = structure of Subtilosin A
| Pfam = PF11420
| Pfam_clan =
| InterPro = IPR021539
| SMART =
| PROSITE =
| MEROPS =
| SCOP =
| TCDB = 1.C.84
| OPM family = 379
| OPM protein = 1pxq
| CAZy =
| CDD =
}}
'''Microcins''' are very small [[bacteriocin]]s, composed of relatively few [[amino acid]]s.  For this reason, they are distinct from their larger [[protein]] cousins.  The classic example is microcin V, of ''[[Escherichia coli]]''. Subtilosin A is another bacteriocin from ''[[Bacillus subtilis]]''. The [[peptide]] has a cyclized backbone and forms three cross-links between the sulphurs of Cys13, Cys7 and Cys4 and the alpha-positions of Phe22, Thr28 and Phe31.<ref name="pmid15035610">{{cite journal |vauthors=Kawulka KE, Sprules T, Diaper CM, Whittal RM, McKay RT, Mercier P, Zuber P, Vederas JC | title = Structure of subtilosin A, a cyclic antimicrobial peptide from Bacillus subtilis with unusual sulfur to alpha-carbon cross-links: formation and reduction of alpha-thio-alpha-amino acid derivatives | journal = Biochemistry | volume = 43 | issue = 12 | pages = 3385–95 |date=March 2004 | pmid = 15035610 | doi = 10.1021/bi0359527 }}</ref>
Microcins produced by [[commensal]] ''E. coli'' strains target and eliminate [[enteric]] pathogens such as ''[[Salmonella enterica]]'' by mimicking the [[siderophore]]s the pathogens use for iron scavenging.<ref>{{Cite journal|url=https://doi.org/10.1038/s41421-021-00253-6|doi=10.1038/s41421-021-00253-6|title=Structure of the mannose phosphotransferase system (Man-PTS) complexed with microcin E492, a pore-forming bacteriocin|year=2021|last1=Huang|first1=Kai|last2=Zeng|first2=Jianwei|last3=Liu|first3=Xueli|last4=Jiang|first4=Tianyu|last5=Wang|first5=Jiawei|journal=Cell Discovery|volume=7|issue=1|page=20|pmid=33820910|pmc=8021565}}</ref> Microcins also help commensal strains of ''E. coli'' outcompete pathogenic strains.<ref name="pmid27798599">{{cite journal| author=Sassone-Corsi M, Nuccio SP, Liu H, Hernandez D, Vu CT, Takahashi AA | display-authors=etal| title=Microcins mediate competition among Enterobacteriaceae in the inflamed gut. | journal=Nature | year= 2016 | volume= 540 | issue= 7632 | pages= 280–283 | pmid=27798599 | doi=10.1038/nature20557 | pmc=5145735 | bibcode=2016Natur.540..280S}} </ref>
BACTIBASE<ref name=Hammami_2007>{{cite journal |title=BACTIBASE: a new web-accessible database for bacteriocin characterization |vauthors=Hammami R, Zouhir A, Ben Hamida J, Fliss I |journal=BMC Microbiology  |year=2007 |volume=7 |pages=89 |pmid=17941971 |doi=10.1186/1471-2180-7-89 |pmc=2211298 |doi-access=free }}</ref><ref name=Hammami_2010>{{cite journal |title=BACTIBASE second release: a database and tool platform for bacteriocin characterization. |vauthors=Hammami R, Zouhir A, Le Lay C, Ben Hamida J, Fliss I |journal=BMC Microbiology  |year=2010 |volume=10 |pages=22 |pmid=20105292 |doi=10.1186/1471-2180-10-22 |pmc=2824694 |doi-access=free }}</ref> database is an open-access database for bacteriocins including microcins.
== References ==
{{Reflist|2}}
[[Category:Bacterial toxins]]
[[Category:Peripheral membrane proteins]]
{{Bacteria-stub}}