biostudies-literatureBury-Mone SNIDDK NIH HHSNIAID NIH HHS5613-22https://www.ebi.ac.uk/biostudies/studies/S-EPMC201111biostudies-literatureUnknown71(10)Ammonia production is of great importance for the gastric pathogen Helicobacter pylori as a nitrogen source, as a compound protecting against gastric acidity, and as a cytotoxic molecule. In addition to urease, H. pylori possesses two aliphatic amidases responsible for ammonia production: AmiE, a classical amidase, and AmiF, a new type of formamidase. Both enzymes are part of a regulatory network consisting of nitrogen metabolism enzymes, including urease and arginase. We examined the role of the H. pylori amidases in vivo by testing the gastric colonization of mice with H. pylori SS1 strains carrying mutations in amiE and/or amiF and in coinfection experiments with wild-type and double mutant strains. A new cassette conferring resistance to gentamicin was used in addition to the kanamycinInfection and immunityPresence of active aliphatic amidases in Helicobacter species able to colonize the stomach.PMC201111AI 38166DK 53727Dailidiene DLabigne ASkouloubris SBerg DEBury-Mone SThiberge JMDauga CDe Reuse HfalsePresence of active aliphatic amidases in Helicobacter species able to colonize the stomach.Ammonia production is of great importance for the gastric pathogen Helicobacter pylori as a nitrogen source, as a compound protecting against gastric acidity, and as a cytotoxic molecule. In addition to urease, H. pylori possesses two aliphatic amidases responsible for ammonia production: AmiE, a classical amidase, and AmiF, a new type of formamidase. Both enzymes are part of a regulatory network consisting of nitrogen metabolism enzymes, including urease and arginase. We examined the role of the H. pylori amidases in vivo by testing the gastric colonization of mice with H. pylori SS1 strains carrying mutations in amiE and/or amiF and in coinfection experiments with wild-type and double mutant strains. A new cassette conferring resistance to gentamicin was used in addition to the kanamycin2003-01-01T00:00:00Z2003 Oct2025-04-21T20:50:23.363Z2019-03-26T22:29:06ZS-EPMC2011111450048110.1128/iai.71.10.5613-5622.200310.1128/IAI.71.10.5613-5622.2003