InterPro domain: IPR011034

Methionyl-tRNA formyltransferase (FMT) ( 2.1.2.9 ) transfers a formyl group onto the amino terminus of the acyl moiety of the methionyl aminoacyl-tRNA. The formyl group appears to play a dual role in the initiator identity of N-formylmethionyl-tRNA by promoting its recognition by IF2 and by impairing its binding to EFTU-GTP. This family also includes formyltetrahydrofolate dehydrogenases, which produce formate from formyl-tetrahydrofolate. These enzymes contain an N-terminal domain in common with other formyl transferase enzymes ( IPR002376 ). The C-terminal domain has an open beta-barrel fold [ 1 ].

The C-terminal domain of FMT structurally resembles methylpurine-DNA glycosylases (MPG). Human 3-methyladenine DNA glycosylase (AAG) catalyses the first step of base excision repair by cleaving damaged bases from DNA, excising a chemically diverse selection of substrate bases damaged by alkylation or deamination [ 2 ].

1. Structure of crystalline Escherichia coli methionyl-tRNA(f)Met formyltransferase: comparison with glycinamide ribonucleotide formyltransferase. EMBO J. 15, 4749-58
2. Molecular basis for discriminating between normal and damaged bases by the human alkyladenine glycosylase, AAG. Proc. Natl. Acad. Sci. U.S.A. 97, 13573-8