Effects of chromosomal deletion of the operon encoding the multiple resistance and pH-related antiporter in Vibrio cholerae.
Ontology highlight
ABSTRACT: To examine the possible physiological significance of Mrp, a multi-subunit cation/proton antiporter from Vibrio cholerae, a chromosomal deletion ?mrp of V. cholerae was constructed and characterized. The resulting mutant showed a consistent early growth defect in LB broth that became more evident at elevated pH of the growth medium and increasing Na+ or K+ loads. After 24 h incubation, these differences disappeared likely due to the concerted effort of other cation pumps in the mrp mutant. Phenotype MicroArray analyses revealed an unexpected systematic defect in nitrogen utilization in the ?mrp mutant that was complemented by using the mrpA'-F operon on an arabinose-inducible expression vector. Deletion of the mrp operon also led to hypermotility, observable on LB and M9 semi-solid agar. Surprisingly, ?mrp mutation resulted in wild-type biofilm formation in M9 despite a growth defect but the reverse was true in LB. Furthermore, the ?mrp strain exhibited higher susceptibility to amphiphilic anions. These pleiotropic phenotypes of the ?mrp mutant demonstrate how the chemiosmotic activity of Mrp contributes to the survival potential of V. cholerae despite the presence of an extended battery of cation/proton antiporters of varying ion selectivity and pH profile operating in the same membrane.
SUBMITTER: Aagesen AM
PROVIDER: S-EPMC5903249 | biostudies-literature | 2016 Dec
REPOSITORIES: biostudies-literature
ACCESS DATA