Molecular characterization of novel pyridoxal-5'-phosphate-dependent enzymes from the human microbiome.

ABSTRACT: Pyridoxal-5'-phosphate or PLP, the active form of vitamin B6, is a highly versatile cofactor that participates in a large number of mechanistically diverse enzymatic reactions in basic metabolism. PLP-dependent enzymes account for ?1.5% of most prokaryotic genomes and are estimated to be involved in ?4% of all catalytic reactions, making this an important class of enzymes. Here, we structurally and functionally characterize three novel PLP-dependent enzymes from bacteria in the human microbiome: two are from Eubacterium rectale, a dominant, nonpathogenic, fecal, Gram-positive bacteria, and the third is from Porphyromonas gingivalis, which plays a major role in human periodontal disease. All adopt the Type I PLP-dependent enzyme fold and structure-guided biochemical analysis enabled functional assignments as tryptophan, aromatic, and probable phosphoserine aminotransferases.

SUBMITTER: Fleischman NM 

PROVIDER: S-EPMC4116655 | biostudies-literature | 2014 Aug

REPOSITORIES: biostudies-literature