To obtain the basic data for evaluating the effects of bacteria-producing nitrite to host cell, the abilities of nitrite production of various bacteria tested the abilities of consumption of self-producing and exogeniously added nitrite, and the
relationship between nitrite production and bacterial growth were examined.
When cultured in RPMI 1640 media without fetal calf serum, E. cloacae and S. marcescens produced nitrite maximally during late lag and early exponential growth phase and E. coli Proteus, P, aeruginosa S. aureus produced nitrite maximally during
mid
exponential growth phase. The amounts of nitrite production of E. cloacae and S. marcescens were profoundly inhibited by adding 5% fetal calf serum into RPMI 1640 media(P<0.05) but those of E. coli Proteus, P. aeruginosa, S. aureus were not
inhibited by
adding 5% fetal calf serum into RPMI 1640 media(P<0.05).
Each concentration (30, 100, 300, 1000μM/ml) of nitrite added exogeniously could be used up 4 or 5 hours after inoculation by E. cloacae, E. coli, Proteus, S. marcescens and 8 or 9 hours after inoculation by P. aeruginosa. The low level
concentration
(30, 100, 300μ M/ml) of nitrite added exogeniously could be used up 4 or 5 hours after inoculation by S. aureus, but high level concentration (1000μM/ml) of nitrite could not be. E. faecium, E. faecalis which could not produce nitrite in RPMI
1640
with or without 5% fetal calf serum could not use up the nitrite added exogeniously
According to these results, in the case of the bacteria producing nitrite during late lag and early exponential phase, the ability of nitrite production could be influenced by adding fetal calf serum into the culture media. The bacteria having
the
nitrite production system could use up the exogenously added nitrite.
The understanding of the production and consumption of nitrite by various bacteria will be useful in evaluating the effects of bacteria-producing nitrite to host cell during infectious diseases caused by these bacteria.
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