Nisin depletes ATP and proton motive force in mycobacteria.
This study examined the inhibitory effect of nisin and its mode of action against Mycobacterium smegmatis, a non-pathogenic species of mycobacteria, and M. bovis-Bacill Carmette Guerin (BCG), a vaccine strain of pathogenic M. bovis. In agar diffusion assays, 2.5 mg ml(-1) nisin was required to inhibit M. bovis-BCG. Nisin caused a slow, gradual, time- and concentration-dependent decrease in internal ATP levels in M. bovis-BCG, but no ATP efflux was detected. In mycobacteria, nisin decreased both components of proton motive force (membrane potential, Delta Psi and Delta pH) in a time- and concentration-dependent manner. However, mycobacteria maintained their intracellular ATP levels during the initial time period of Delta Psi and Delta pH dissipation. These data suggest that the mechanism of nisin in mycobacteria is similar to that in food-borne pathogens.
Chung
H J
HJ
Cook College, Department of Food Science, Rutgers--The State University of New Jersey, New Brunswick, NJ 08901-8520, USA.
Montville
T J
TJ
Chikindas
M L
ML
D000255:Adenosine Triphosphate / Q000378:metabolism*; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D009161:Mycobacterium / Q000187:drug effects*; D009163:Mycobacterium bovis / Q000187:drug effects; D020102:Mycobacterium smegmatis / Q000187:drug effects; D009561:Nisin / Q000494:pharmacology*; D018892:Proton-Motive Force / Q000187:drug effects*
D000900:Anti-Bacterial Agents; D009561:Nisin; D000255:Adenosine Triphosphate