DENITRIFICATION BY ACTINOMYCETES AND PURIFICATION OF DISSIMILATORY NITRITE REDUCTASE AND AZURIN FROM STREPTOMYCES-THIOLUTEUS

Many actinomycete strains are able to convert nitrate or nitrite to ni trous oxide (N2O), As a representative of actinomycete denitrification systems, the system of Streptomyces thioluteus was investigated in de tail. S. thioluteus attained distinct cell growth upon anaerobic incub ation with nitrate or nitrite with concomitant and stoichiometric conv ersion of nitrate or nitrite to N2O, suggesting that the denitrificati on acts as anaerobic respiration. Furthermore, a copper-containing, di ssimilatory nitrite reductase (CuNir) and its physiological electron d onor, azurin, were isolated. This is the first report to show that den itrification generally occurs among actinomycetes.