Gv. Carbonell et al., CULTURE CONDITIONS AFFECT CYTOTOXIN PRODUCTION BY SERRATIA-MARCESCENS, FEMS immunology and medical microbiology, 16(3-4), 1996, pp. 299-307
Cytotoxins have been implicated in the pathogenesis of bacterial infec
tions. In this study, the influence of different culture conditions wa
s evaluated on cytotoxin production by Serratia marcescens. Parameters
such as culture media, incubation temperature, starting pH of culture
medium, aeration, anaerobiosis, carbon sources, iron concentration in
the culture media, and release of cell-bound toxin by polymyxin B wer
e investigated. The data suggest that this cytotoxin is predominantly
extracellular and is not induced by iron limitation. Aerobic culture w
ith shaking resulted in higher cytotoxicity than static aerobic or ana
erobic culture. Bacteria grown in glucose, sucrose or galactose were m
ore cytotoxic than those grown in inositol or maltose. The culture con
ditions that were identified as optimal for cytotoxin production by Se
rratia marcescens were incubation temperature ranging from 30 to 37 de
grees C, in medium adjusted to pH 8.5, with shaking. This work will co
ntribute to further studies on the identification of this cytotoxic ac
tivity.