Alkyl hydroperoxide reductase from Bacillus aquimaris MKSC 6.2 protects Esherichia coli from oxidative stress

Alkyl hydroperoxide reductase genes ( ahpCF ) from the soft coral associated Bacillus aquimaris MKSC6.2 have been isolated. The cloned 546 bp ahpC gene encodes a 181 amino acid residues polypeptide. The AhpC belongs to typical 2‐Cys peroxiredoxin (Prx) containing conserved peroxidatic cysteine residue (C 46 ) required for hydroperoxide reduction and conserved resolving cysteine (C 166 ). The isolated 1530 bp ahpF gene encodes a polypeptide of 509 amino acid residues with two conserved C 128 HNC 131 and C 337 PHC 340 catalytic residues required for reduction of oxidized‐AhpC during catalytic turnover. A survival study with Escherichia coli showed that overexpression of AhpC and AhpF resulted in a total protection against 0.16 mM t‐butyl hydroperoxide.