Previous Article | Next Article ![]()
Appl. Environ. Microbiol., Jul 1997, 2679-2685, Vol 63, No. 7
B O'Driscoll, CGM Gahan and C Hill
Listeria monocytogenes is capable of withstanding low pH after initial
exposure to sublethal acidic conditions, a phenomenon termed the acid
tolerance response (B. O'Driscoll, C. G. M. Gahan, and C. Hill, Appl.
Environ. Microbiol. 62:1693-1698, 1996). Treatment of L. monocytogenes LO28
with chloramphenicol during acid adaptation abrogated the protective
effect, suggesting that de novo protein synthesis is required for the acid
tolerance response. Analysis of protein expression during acid adaptation
by two-dimensional gel electrophoresis revealed changes in the levels of 53
proteins. Significant protein differences were also evident between
nonadapted L. monocytogenes LO28 and a constitutively acid-tolerant mutant,
ATM56. In addition, the analysis[S_TABC] revealed differences in protein
expression between cells induced with a weak acid (lactic acid) and those
induced with a strong acid (HCl). Comparison of both acid-adapted LO28 and
ATM56 revealed that both are capable of maintaining their internal pH
(pH(infi)) at higher levels than nonadapted control cells during severe
acid stress. Collectively, the data demonstrate the profound alterations in
protein synthesis which take place during acid adaptation in L.
monocytogenes and ultimately lead to an increased ability to survive severe
stress conditions.
Copyright © 1997, American Society for Microbiology
Two-Dimensional Polyacrylamide Gel Electrophoresis Analysis of the Acid Tolerance Response in Listeria monocytogenes LO28
Microbiology Department & National Food Biotechnology Centre, University College Cork, Cork, Ireland
This article has been cited by other articles:
| J. Bacteriol. | Microbiol. Mol. Biol. Rev. | Eukaryot. Cell | All ASM Journals |
|---|