MoaE Is Involved in Response to Oxidative Stress in .

Molybdenum ions are covalently bound to molybdenum pterin (MPT) to produce molybdenum cofactor (Moco), a compound essential for the catalytic activity of molybdenum enzymes, which is involved in a variety of biological functions. MoaE is the large subunit of MPT synthase and plays a key role in Moco synthesis. Here, we investigated the function of MoaE in (DrMoaE) in vitro and in vivo, demonstrating that the protein contributed to the extreme resistance of . The crystal structure of DrMoaE was determined by 1.9 Å resolution. DrMoaE was shown to be a dimer and the dimerization disappeared after Arg110 had been mutated. The deletion of resulted in sensitivity to DNA damage stress and a slower growth rate in . The increase in transcript levels the and accumulation of intracellular reactive oxygen species levels under oxidative stress suggested that it was involved in the antioxidant process in . In addition, treatment with the base analog 6-hydroxyaminopurine decreased survival and increased intracellular mutation rates in deletion mutant strains. Our results reveal that MoaE plays a role in response to external stress mainly through oxidative stress resistance mechanisms in .