InterPro domain: IPR006222

This domain is found at the N terminus of glycine cleavage T-proteins, which are part of the glycine cleavage multienzyme complex (GCV) found in bacteria and the mitochondria of eukaryotes. GCV catalyses the catabolism of glycine in eukaryotes. The T-protein (aminomethyltransferase, 2.1.2.10 ) is a folate-dependent enzyme that catalyses the release of ammonia and the transfer of the methylene carbon unit (C1 unit) to tetrahydrofolate (H4folate) from the aminomethyl intermediate attached to the lipoate cofactor of H-protein [ 1 , 2 ].

This domain is also found in YgfZ proteins. YgfZ in E.coli is a folate binding protein involved in RNA modification and regulation of chromosomal replication initiation [ 3 ]. YgfZ is not an aminomethyltransferase but is likely a folate-dependent regulatory protein [ 4 ]. This domain could represent a folate-binding domain.

1. Cloning, and molecular characterization of the GCV1 gene encoding the glycine cleavage T-protein from Saccharomyces cerevisiae. Gene 186, 13-20
2. Crystal structure of human T-protein of glycine cleavage system at 2.0 A resolution and its implication for understanding non-ketotic hyperglycinemia. J. Mol. Biol. 351, 1146-59
3. Involvement of the Escherichia coli folate-binding protein YgfZ in RNA modification and regulation of chromosomal replication initiation. Mol. Microbiol. 59, 265-75
4. Crystal structure of the YgfZ protein from Escherichia coli suggests a folate-dependent regulatory role in one-carbon metabolism. J. Bacteriol. 186, 7134-40