A shaE Deletion Mutant Showed Lower Na~+ Sensitivity Compared to Other Deletion Mutants in the Bacillus subtilis Sodium/Hydrogen Antiporter (Sha) System

摘要

The sodium/hydrogen antiporter (Sha, identical to multiple resistance and pH adaptation: Mrp) encoded by shaABCDEFG is considered to be the major Na~+ excretion system in Bacillus subtilis. We constructed deletion mutants of each sha (=mrp) gene and found that a shaE mutant showed lower Na~+ sensitivity compared to the other mutants with respect to the growth, sporulation and Na~+ efflux activity. ShaE may have a dissimilar role top other Sha proteins in transport functions.