Role of an ABC importer in Mycobacterial drug resistance

Abstract

Phosphate specific transporter (Pst) in bacteria is involved in phosphate transport. Pst is a multisubunit system which belongs to the ABC family of transporters. The import function of this transporter is known to be operative at media phosphate concentrations below the millimolar range. However, we found amplification of this transporter in a laboratory generated ciprofloxacin resistant Mycobacterium smegmatis colony (CIP^r) which was grown in a condition when phosphate scavenging function of this operon was inoperative. Our results therefore argue the role of this ABC importer in conferring high level of fluoroquinolone resistance in CIP^r.