CLONING AND SEQUENCING OF THE NHAB GENE ENCODING AN NA+ H+ ANTIPORTERFROM VIBRIO-ALGINOLYTICUS/

A gene has been cloned from the marine bacterium Vibrio alginolyticus that functionally complements a mutant strain of Escherichia coli, TO1 14, defective in three Na+/H+ antiport genes (nhaA, nhaB, chaA). The n ucleotide sequence of the cloned fragment revealed an open reading fra me, which encodes a protein with a predicted 528 amino acid sequence a nd molecular mass of 57212 Da. This gene has 62% identity to nhaB gene at the DNA level from Escherichia coli and the deduced amino acid seq uence is 67% identical with E. coli NhaB. This gene is presumably the V. alginolyticus nhaB gene and will be named nhaBv.