The Rhizobium meliloti bacA gene encodes a function that is essential for bacterial differentiation into bacteroids within plant cells in the symbiosis between R. meliloti and alfalfa. An Escherichia coli homolog of BacA, SbmA, is implicated in the uptake of microcins and bleomycin. This family is likely to be a subfamily of the ABC transporter family.

1: Genetic analysis of the Rhizobium meliloti bacA gene: functional interchangeability with the Escherichia coli sbmA gene and phenotypes of mutants. Ichige A, Walker GC; J Bacteriol 1997;179:209-216. PMID:8982000