豌豆根瘤菌透性酶基因突变体的构建及其功能研究

Construction and Function of Permease Gene Mutant in Rhizobium leguminosarum

为研究豌豆根瘤菌(Rhizobium leguminosarum)3841透性酶基因rl1568的作用,通过同源重组构建了豌豆根瘤菌透性酶基因rl1568突变体。结果表明,rl1568基因突变不影响菌株在自生培养条件下生长,但该基因突变株对低浓度的氧化物十分敏感且生长较差。荧光定量RT-PCR结果表明,H2O2不能诱导rl1568基因表达。植物盆栽试验发现rl1568基因突变对根瘤菌共生固氮能力无影响。

This study investigated the role of the permease gene rl1568 in Rhizobium species strain 3841,rl1568 knockout R.leguminosarum strain was constructed by homologous recombination. Under the free-living conditions,the rl1568 mutant exhibited no generation time extension. However,cells of the rl1568 mutant strain were sensitive and deficient in consumption of low concentrations of peroxide. The q RT-PCR results showed that rl1568 was expressed independently of exogenous H2O2.With regard to symbiotic capacities with Pisum sativum,there was no different between the rl1568 mutant and the wild type in root nodule nitogenase activity.