Split MutT prevents the mutator phenotype of mutT-deficient Escherichia coli

BackgroundThe Escherichia coli MutT (NudA) protein catalyzes the hydrolysis of an oxidized form of dGTP, 8-oxo-7,8-dihydro-dGTP (8-hydroxy-dGTP), and the spontaneous mutation frequency is elevated in E. coli cells deficient in the mutT gene. ResultsA split MutT, comprising the N-terminal (residues 1-95) and C-terminal (residues 96-129) peptides, was designed based on the known tertiary structure and linker insertion mutagenesis experiments. The mutator phenotype was complemented when the two peptides were separately expressed in mutT E. coli cells. ConclusionsThese results indicated that this split MutT functions as a nucleotide pool sanitization enzyme in vivo.