Open AccessA major chemotaxis gene cluster in Azospirillum brasilense and relationships between chemotaxis operons in α‐proteobacteria
Author(s) -
Hauwaerts Dieter,
Alexandre Gladys,
Das Subrata K,
Vanderleyden Jos,
Zhulin Igor B
Publication year - 2002
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 - 10.1111/j.1574-6968.2002.tb11061.x
Subject(s) - azospirillum brasilense , chemotaxis , operon , biology , complementation , genetics , gene , mutant , gene cluster , microbiology and biotechnology , bacteria , microbial inoculant , receptor
Azospirillum brasilense shows chemotaxis to a variety of nutrients and oxygen. Genes encoding the central signal transduction pathway in chemotaxis were identified by phenotypic complementation of generally non‐chemotactic mutants. Sequencing of a DNA fragment, which complemented two different mutants, revealed a region of five open reading frames translated in one direction and encoding homologs of known genes comprising excitation and adaptation pathways for chemotaxis in other bacterial species. The major chemotaxis gene cluster appears to be essential for all known behavioral responses that direct swimming motility in A. brasilense . Phylogenetic and genomic analysis revealed three groups of chemotaxis operons in α‐proteobacterial species and assigned the A. brasilense operon to one of them. Interestingly, operons that are shown to be major regulators of behavior in several α‐proteobacterial species are not orthologous.