在低铁水平下生长的固氮螺菌的固氮酶活性需要nifXorf1基因的产物。

Nitrogenase activity of Herbaspirillum seropedicae grown under low iron levels requires the products of nifXorf1 genes.

作者信息

Klassen Giseli, de Oliveira Pedrosa Fábio, de Souza Emanuel M, Yates M Geoffrey, Rigo Liu Un

机构信息

Departamento de Patologia Básica, Universidade Federal do Paraná, CP 19046, 81531-990 Curitiba PR, Brazil.

出版信息

FEMS Microbiol Lett. 2003 Jul 29;224(2):255-9. doi: 10.1016/S0378-1097(03)00453-1.

DOI:10.1016/S0378-1097(03)00453-1

PMID:12892890

Abstract

Herbaspirillum seropedicae strains mutated in the nifX or orf1 genes showed 90% or 50% reduction in nitrogenase activity under low levels of iron or molybdenum respectively. Mutations in nifX or orf1 genes did not affect nif gene expression since a nifH::lacZ fusion was fully active in both mutants. nifX and the contiguous gene orf1 are essential for maximum nitrogen fixation under iron limitation and are probably involved in synthesis of nitrogenase iron or iron-molybdenum clusters.

摘要

在nifX或orf1基因中发生突变的血清固氮螺菌菌株，在低铁或低钼水平下，固氮酶活性分别降低了90%或50%。nifX或orf1基因的突变并不影响nif基因的表达，因为nifH::lacZ融合在这两种突变体中都具有完全活性。nifX和相邻的orf1基因对于铁限制条件下的最大固氮作用至关重要，可能参与固氮酶铁或铁钼簇的合成。