title: Glycogen phosphorylase sequences from the amitochondriate protists, Trichomonas vaginalis, Mastigamoeba balamuthi, Entamoeba histolytica and Giardia intestinalis.
abstract: Glycogen phosphorylase genes or messages from four amitochondriate eukaryotes, Trichomonas vaginalis, Mastigamoeba balamuthi, Entamoeba histolytica (two genes) and Giardia intestinalis, have been isolated and sequenced. The sequences of the amitochondriate protist enzymes appear to share a most recent common ancestor. The clade containing these sequences is closest to that of another protist, the slime mold (Dictyostelium discoideum), and is more closely related to fungal and plant phosphorylases than to mammalian and eubacterial homologs. Structure-based amino acid alignment shows conservation of the residues and domains involved in catalysis and allosteric regulation by glucose 6-phosphate but high divergence at domains involved in phosphorylation-dependent regulation and AMP binding in fungi and animals. Protist phosphorylases, as their prokaryotic and plant counterparts, are probably not regulated by phosphorylation.
authors.affiliation: The Rockefeller University, 1230 York Avenue, New York, NY 10021, USA. wug@mail.rockefeller.edu
authors.forename: Gang
authors.initials: G
authors.lastname: Wu
authors.forename: Miklós
authors.initials: M
authors.lastname: Müller
mesh_terms: D000595:Amino Acid Sequence; D000656:Amoeba / Q000201:enzymology* / Q000235:genetics; D000818:Animals; D001483:Base Sequence; D016054:DNA, Protozoan / Q000737:chemistry / Q000235:genetics; D004748:Entamoeba histolytica / Q000201:enzymology* / Q000235:genetics; D016829:Giardia lamblia / Q000201:enzymology* / Q000235:genetics; D024981:Glycogen Phosphorylase / Q000235:genetics*; D008969:Molecular Sequence Data; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D016415:Sequence Alignment; D014246:Trichomonas vaginalis / Q000201:enzymology* / Q000235:genetics
chemical_list: D016054:DNA, Protozoan; D024981:Glycogen Phosphorylase