Nitrogenase Activity of Rhizobium japonicum Growing on Agar Surfaces in Relation to Slime Production, Growth and Survival
1978; Microbiology Society; Volume: 108; Issue: 1 Linguagem: Inglês
10.1099/00221287-108-1-151
ISSN2059-9323
Autores Tópico(s)Mycorrhizal Fungi and Plant Interactions
ResumoA reproducible, simple method for assessing nitrogenase activity by the acetylene reduction test on agar plates is described. The effects of phosphate, succinate and arabinose on nitrogenase activity and slime production by R. japonicum strain 61-a-101, growing on a solid medium with leucine or glutamine as sole source of fixed nitrogen, were investigated. Slime production varied with different media but there was no simple correlation between slime production and high nitrogenase activity. Arabinose greatly enhanced nitrogenase activity of bacteria growing on glutamine as sole nitrogen source, especially if the amino acid concentration was 1 mm or less. Without arabinose, the optimum concentration of glutamine for nitrogenase activity was 2 to 2·5 mm, but 1 mm-glutamine plus 50 mm-arabinose gave twice the activity [8 to 10 nmol ethylene produced h–1 (mg protein)–1].
Referência(s)