The nitrogen nutrition of soil and herbage coryneform bacteria.

Abstract

SummaryThe nitrogen nutrition of 93 strains of soil and herbage coryneform bacteria and 16 named strains of Arthrobacter and Cellulomonas was examined. In testing for the ability of coryneform bacteria to utilize inorganic nitrogen as sole nitrogen source it was found necessary to use a medium containing a balanced mineral base and a suitable metal chelating agent in order to obtain reproducible results. A suitable medium is described. When provided with essential vitamins, 90% of soil isolates utilized inorganic nitrogen as sole nitrogen source while only 30% of herbage isolates did so. Sixty per cent of herbage isolates utilized inorganic nitrogen as major nitrogen source when provided with l‐methionine in addition to vitamins, whereas no soil isolate showed a requirement for methionine. For a small residue of strains from each habitat the substrate nitrogen requirements were not determined. Of the named strains examined A. terregens utilized inorganic nitrogen as major nitrogen source when provided with methionine and vitamins while the remainder utilized inorganic nitrogen as sole nitrogen source. For 4 Arthrobacter spp. the nitrogen requirements described differ from those previously reported.