An operon encoding a novel ABC-type transport system in Bacillus subtilis

Downstream from the surfactin synthetase operon in Bacillus subtilis a new operon-type structure has been localized which, on the basis of sequence determination, potentially encodes an ABC-type transport system. The 268 amino acid protein, the product of orf1, represents the solute-binding component of the system whereas the orf2 product, a 234 amino acid protein, is the transmembrane component. Finally orf3 potentially encodes a typical 241 amino acid ATP-binding protein involved in energy supply. Comparison of the three proteins with the subunits of other ABC-type systems suggests that this new system is involved in amino acid transport.