This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Wu, Q. Articles by Knowles, R. Search for Related Content PubMed PubMed Citation Articles by Wu, Q. Articles by Knowles, R. Agricola Articles by Wu, Q. Articles by Knowles, R.

 Previous Article  |  Next Article 

Appl. Environ. Microbiol., Feb 1995, 434-437, Vol 61, No. 2
Copyright © 1995, American Society for Microbiology

Effect of Chloramphenicol on Denitrification in Flexibacter canadensis and "Pseudomonas denitrificans"

Q Wu and R Knowles
Microbiology Unit, Department of Natural Resource Sciences, McGill University, Macdonald Campus, Ste. Anne de Bellevue, Quebec H9X 3V9, Canada

It was recently reported that chloramphenicol inhibits existing denitrification enzyme activity in sediments and carbon-starved cultures of "Pseudomonas denitrificans." Therefore, we studied the effect of chloramphenicol on denitrification by Flexibacter canadensis and "P. denitrificans." Production of N(inf2)O from nitrate by F. canadensis cells decreased as the concentration of chloramphenicol was increased, and 10.0 mM chloramphenicol completely inhibited N(inf2)O production. "P. denitrificans" was less sensitive to chloramphenicol, and production of N(inf2)O from nitrate was inhibited by only about 50% even in the presence of 10.0 mM chloramphenicol. These results suggested that inhibition of denitrification enzyme activity depended on the concentration of chloramphenicol. Increasing the concentration of chloramphenicol decreased the rate of production of nitrite from nitrate by F. canadensis cells, and the concentration of chloramphenicol which resulted in 50% inhibition of production of nitrite from nitrate was 2.5 mM. In contrast, the rates of production of nitrite from nitrate by intact cells and cell extracts of "P. denitrificans" were inhibited by only 58 and 54%, respectively, at a chloramphenicol concentration of 10.0 mM. Chloramphenicol caused accumulation of NO from nitrite but not from nitrate and inhibited NO consumption in F. canadensis; however, it had neither effect in "P. denitrificans." Chloramphenicol did not affect N(inf2)O consumption by these organisms. We concluded that chloramphenicol inhibits denitrification at the level of nitrate reduction and, in F. canadensis, also at the level of NO reduction.

This article has been cited by other articles:

• Murray, R. E., Knowles, R. (1999). Chloramphenicol Inhibition of Denitrifying Enzyme Activity in Two Agricultural Soils. Appl. Environ. Microbiol. 65: 3487-3492 [Abstract] [Full Text]