Ampicillin bacteriocidal or static
peter.cherepanov at uz.kuleuven.ac.be
Wed Mar 13 16:12:12 EST 2002
shall we make a formal definition of "clinic death" for E. coli ?
Is it when protein synthesis stopped or ATP levels dropped to 0.01% of
Or when 90% of intracellular soluble protein leaked out into the medium?
What is a chance of recovery from such a state? -not zero, I think. In such
"half dead" state few cells can sleep over the danger, and then come back to
life giving rize to satellite colonies (when levels of ampicilline drop
below some critical levels, <10 ug/ml?).
Also, E. coli easily develops spontaneous resistance to low levels of
antibiotics (multiple antibiotic resistance, marR or "smar"; I think, it is
a pump, if I am not mistaken), you can even "train" (select) bacteria on
increasing concentrations of antibiotics to get clones resistant to quite
high antibiotic concetrations ...
(Ap, Tc, Km - whatever you want ...).
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