Open AccessOxidative consumption of nitric oxide by heterotrophic bacteria in soil
Author(s) -
Baumgärtner Manfred,
Koschorreck Matthias,
Conrad Ralf
Publication year - 1996
Publication title -
fems microbiology ecology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.377
H-Index - 155
eISSN - 1574-6941
pISSN - 0168-6496
DOI - 10.1111/j.1574-6941.1996.tb00209.x
Subject(s) - heterotroph , biology , nitrate , incubation , bacteria , nitrite , denitrification , anoxic waters , aerobic denitrification , cambisol , yeast extract , environmental chemistry , food science , microbiology and biotechnology , denitrifying bacteria , soil water , biochemistry , nitrogen , chemistry , ecology , genetics , organic chemistry
Uptake rate constants for nitric oxide were measured in a neutral calcic cambisol (KBE) and an acidic luvisol (PBE). The NO uptake was higher under oxic than under anoxic incubation conditions by a factor of about three. Gassing the soils with air containing 10 ppmv NO resulted in the accumulation of nitrate which accounted for 57–94% of the NO consumed. Aerobic heterotrophic bacteria were isolated on glucose‐yeast extract medium from soil dilutions corresponding to a most probable number of 10 8 –10 9 bacteria per gram dry weight soil. One of the isolates (strain PS88, a Pseudomonas sp.) exhibited NO consumption activity that was much higher under oxic than anoxic incubation conditions. When sterile KBE amended with strain PS88 was gassed with air containing 10 ppmv NO, 88% of the consumed NO was recovered as nitrate and nitrite. A screening of various bacteria obtained from culture collections showed a widespread ability for consumption of low NO concentrations. Our results indicate that NO consumption in soil is not only possible by reductive denitrification, but also by oxidation due to aerobic heterotrophic bacteria such as strain PS88.