The C-terminal receiver domain of the Rhizobium leguminosarum bv. viciae FixL protein is required for free-living microaerobic induction of the fnrN promoter.

The Rhizobium leguminosarum bv. viciae VF39 FixL protein belongs to a distinct group of hybrid regulatory sensor proteins that bear a covalently linked C-terminal receiver domain. FixL has an unorthodox histidine kinase domain, which is shared with many other hybrid regulators.

The Rhizobium leguminosarum bv. viciae VF39 gamma-aminobutyrate (GABA) aminotransferase gene (gabT) is induced by GABA and highly expressed in bacteroids.

A Rhizobium leguminosarum bv. viciae VF39 gene (gabT) encoding a gamma-aminobutyrate (GABA) aminotransferase was identified, cloned and characterized. This gene is thought to be involved in GABA metabolism via the GABA shunt pathway, a theoretical bypass of the 2-oxoglutarate dehydrogenase complex.