Augmentation of killing of Escherichia coli O157 by combinations of lactate, ethanol, and low-pH conditions.
نویسندگان
چکیده
The acid tolerance of Escherichia coli O157:H7 strains can be overcome by addition of lactate, ethanol, or a combination of the two agents. Killing can be increased by as much as 4 log units in the first 5 min of incubation at pH 3 even for the most acid-tolerant isolates. Exponential-phase, habituated, and stationary-phase cells are all sensitive to incubation with lactate and ethanol. Killing correlates with disruption of the capacity for pH homeostasis. Habituated and stationary-phase cells can partially offset the effects of the lowering of cytoplasmic pH.
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عنوان ژورنال:
- Applied and environmental microbiology
دوره 65 3 شماره
صفحات -
تاریخ انتشار 1999