NOVEL PHOSPHOTRANSFERASE SYSTEM GENES REVEALED BY BACTERIAL GENOME ANALYSIS - A GENE-CLUSTER ENCODING A UNIQUE ENZYME-I AND THE PROTEINS OFA FRUCTOSE-LIKE PERMEASE SYSTEM

Previous publications have demonstrated tire presence of a cryptic gen e encoding a novel Enzyme I of the phosphoenolpyruvate:sugar phosphotr ansferase system (PTS). Recent Escherichia coli genome sequencing reve aled a gene (ptsA) encoding a new Enzyme I homologue in the 89.1-89.3 centisome region. We have analysed this region, and here describe and characterize open reading frames (ORFs) encoding (1) a fused PTS Enzym e I-IIA(Fru) homologue, (2) a glycerol dehydrogenase, (3) a transaldol ase homologue, (4) two PTS IIBFru homologues, (5) a PTS IICFru homolog ue, and (6) homologues of pyruvate formate-lyase and its activating en zyme. Binary comparison scores, multiple alignments and phylogenetic t rees establish the families of proteins to which each of the relevant ORFs belong. Identification of the putative products of this gene clus ter leads to the proposal that several of the proteins encoded in this region function in anaerobic carbon metabolism.