【摘要】 由谷子根表分离到一株阴沟肠杆菌。该菌振荡培养于诱导培养液中,在30℃下21—24小时,其最高乙炔还原速率为576n mol C₂H₄/mg蛋白/h。而在厌氧条件下则可达1479n mol C₂H₄/mg蛋白/h。在正常氧浓度下,该菌培养4—96小时之间皆可检测出固氮活性。不同浓度的NH₄⁺明显抑制其固氮活性。在碱性条件下固氮活性较高。更多还原

【Abstract】 Enterobacter cloacae C022 was isolated from root surfaces of millet on the farm of Shanxi Academy of Agricultural Sciences. The strain C022 was grown in the induceing culture solution with shaking 21—24h at 30℃, the highest rate of acetylene reduction was 576n mol/mg protein/h. But it would reach 1479 n mol/mg protein/h under the anaerobic condition. When it was incubated in the pure culture at a normal concentration of O₂, its N₂-fixing activity was suppressed apparently. And the N₂-fixing activity of pure culture could be detected at the normal concentration of O₂ during 4—96 h. The N₂-fixing activity of pure culture may be evidently inhibited by different concentrations of NH₄Ac. The pure culture showed higher N₂-fixing activity under more basic conditions.更多还原