Open AccessNitrogenase activity of Herbaspirillum seropedicae grown under low iron levels requires the products of nifXorf1 genes
Author(s) -
Klassen Giseli,
Oliveira Pedrosa Fábio,
Souza Emanuel M.,
Yates M.Geoffrey,
Rigo Liu Un
Publication year - 2003
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1016/s0378-1097(03)00453-1
Subject(s) - nitrogenase , microbiology and biotechnology , chemistry , gene , diazotroph , bacteria , biology , biochemistry , nitrogen fixation , genetics
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.