title: Mutagenesis identifies a conserved tyrosine residue important for the activity of uroporphyrinogen III synthase from Anacystis nidulans.
abstract: Uroporphyrinogen III synthase from the cyanobacterium Anacystis nidulans was overproduced in Escherichia coli and analyzed by site specific mutagenesis. Of the nine conserved amino acids altered, only a single tyrosine mutant (Y166F) showed any significant decrease in activity suggesting this residue is critical for proper substrate binding and/or catalysis.
authors.affiliation: Center for Biological NMR, Department of Chemsitry, P.O. Box 30012, Texas A&M University, College Station, TX 77842-3012, USA. c-roessner@tamu.edu
authors.forename: Charles A
authors.initials: CA
authors.lastname: Roessner
authors.forename: Krishan
authors.initials: K
authors.lastname: Ponnamperuma
authors.forename: A I
authors.initials: AI
authors.lastname: Scott
mesh_terms: D000595:Amino Acid Sequence; D019943:Amino Acid Substitution; D002384:Catalysis; D002851:Chromatography, High Pressure Liquid; D017124:Conserved Sequence; D000458:Cyanobacteria / Q000201:enzymology*; D004591:Electrophoresis, Polyacrylamide Gel; D004789:Enzyme Activation / Q000502:physiology; D008969:Molecular Sequence Data; D015394:Molecular Structure; D016297:Mutagenesis, Site-Directed; D013329:Structure-Activity Relationship; D014443:Tyrosine / Q000235:genetics / Q000378:metabolism*; D014576:Uroporphyrinogen III Synthetase / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*
chemical_list: D014443:Tyrosine; D014576:Uroporphyrinogen III Synthetase