Increased ATPase activity is responsible for acid sensitivity of nisin-resistant Listeria monocytogenes ATCC 700302.
The growth of the foodborne pathogen Listeria monocytogenes can be controlled by nisin, an antimicrobial peptide. A spontaneous mutant of L. monocytogenes shows both resistance to nisin and increased acid sensitivity compared to the wild type. Changes in the cell membrane correlated with nisin resistance, but the mechanism for acid sensitivity appears unrelated. When hydrochloric or lactic acid is added to cultures, intracellular ATP levels drop significantly in the mutant (P < 0.01) compared to the results seen with the wild type. Characterization of the F(0)F(1) ATPase, which hydrolyzes ATP to pump protons from the cell cytoplasm, shows that the enzyme is more active in the mutant than in the wild type. These data support a model in which the increased activity of the mutant ATPase upon acid addition depletes the cells' supply of ATP, resulting in cell death.
McEntire
Jennifer Cleveland
JC
Department of Food Science, New Jersey Agricultural Experiment Station, Rutgers, The State University of New Jersey, New Brunswick, New Jersey 08901, USA.
Carman
George M
GM
Montville
Thomas J
TJ
D000251:Adenosine Triphosphatases / Q000378:metabolism*; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D024881:Drug Resistance, Bacterial; D006851:Hydrochloric Acid / Q000494:pharmacology*; D006863:Hydrogen-Ion Concentration; D019344:Lactic Acid / Q000494:pharmacology*; D008089:Listeria monocytogenes / Q000187:drug effects* / Q000235:genetics / Q000254:growth & development; D009561:Nisin / Q000494:pharmacology; D015854:Up-Regulation
D000900:Anti-Bacterial Agents; D009561:Nisin; D019344:Lactic Acid; D000251:Adenosine Triphosphatases; D006851:Hydrochloric Acid