{{Short description|Bacterial gene}} {{Infobox nonhuman protein |Name=Nicotinamidase/pyrazinamidase |Symbol=pncA |UniProt=I6XD65 |Organism=Mycobacterium tuberculosis }} '''PncA''' is a bacterial gene encoding a nicotinamidase that doubles as a '''pyrazinamidase''' in ''Mycobacterium'' species.<ref name="pmid8640557">{{cite journal |vauthors=Scorpio A, Zhang Y |title=Mutations in pncA, a gene encoding pyrazinamidase/nicotinamidase, cause resistance to the antituberculous drug pyrazinamide in tubercle bacillus |journal=Nat. Med. |volume=2 |issue=6 |pages=662–7 |date=June 1996 |pmid=8640557 |doi= 10.1038/nm0696-662|s2cid=8579133 }}</ref> Nicotinamidase converts nicotinamide to nicotinic acid where as pyrazinamidase converts the drug pyrazinamide to its active form pyrazinoic acid.<ref>{{Cite journal|last1=Whitfield|first1=Michael G.|last2=Soeters|first2=Heidi M.|last3=Warren|first3=Robin M.|last4=York|first4=Talita|last5=Sampson|first5=Samantha L.|last6=Streicher|first6=Elizabeth M.|last7=Helden|first7=Paul D. van|last8=Rie|first8=Annelies van|date=2015-07-28|title=A Global Perspective on Pyrazinamide Resistance: Systematic Review and Meta-Analysis|journal=PLOS ONE|volume=10|issue=7|article-number=e0133869|doi=10.1371/journal.pone.0133869|issn=1932-6203|pmc=4517823|pmid=26218737|bibcode=2015PLoSO..1033869W|doi-access=free}}</ref>
Missense mutations in this gene in ''Mycobacterium'' is strongly correlated with resistance to pyrazinamide, likely due to a loss of the ability to produce pyrazinoic acid.<ref name=Jureen>{{Cite journal|last1=Juréen|first1=Pontus|last2=Werngren|first2=Jim|last3=Toro|first3=Juan-Carlos|last4=Hoffner|first4=Sven|date=2016-12-15|title=Pyrazinamide Resistance and pncA Gene Mutations in Mycobacterium tuberculosis|journal=Antimicrobial Agents and Chemotherapy|volume=52|issue=5|pages=1852–1854|doi=10.1128/AAC.00110-08|issn=0066-4804|pmc=2346646|pmid=18316515}}</ref> Mutagenesis data indicates that many loss-of-function mutations differentially affect the enzyme's ability to convert nicotinamide and pyrazinamide.<ref name="I6XD65">{{cite web |title=I6XD65 |url=https://www.uniprot.org/uniprotkb/I6XD65 |website=UniProt |language=en}}</ref>
The H57D resistance mutation is "typical of" ''M. bovis''.<ref name=Jureen/>
The symbol ''PncA'' is also used for the orthologous nicotinamidase in other bacterial species, including ''E. coli''.<ref>{{cite web |title=P21369 |url=https://www.uniprot.org/uniprotkb/P21369/entry#family_and_domains |website=UniProt |language=en}}</ref>
== See also == * Pyrazinamide
== References == {{reflist}}
Category:Enzymes Category:Prokaryote genes Category:Tuberculosis
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