title: Identification and analysis of genes involved in anaerobic toluene metabolism by strain T1: putative role of a glycine free radical.
abstract: The denitrifying strain T1 is able to grow with toluene serving as its sole carbon source. Two mutants which have defects in this toluene utilization pathway have been characterized. A clone has been isolated, and subclones which contain tutD and tutE, two genes in the T1 toluene metabolic pathway, have been generated. The tutD gene codes for an 864-amino-acid protein with a calculated molecular mass of 97,600 Da. The tutE gene codes for a 375-amino-acid protein with a calculated molecular mass of 41,300 Da. Two additional small open reading frames have been identified, but their role is not known. The TutE protein has homology to pyruvate formate-lyase activating enzymes. The TutD protein has homology to pyruvate formate-lyase enzymes, including a conserved cysteine residue at the active site and a conserved glycine residue that is activated to a free radical in this enzyme. Site-directed mutagenesis of these two conserved amino acids shows that they are also essential for the function of TutD.
authors.affiliation: Department of Biological Sciences, Ohio University, Athens 45701-2979, USA. Coschiga@ohiou.edu
authors.forename: P W
authors.initials: PW
authors.lastname: Coschigano
authors.forename: T S
authors.initials: TS
authors.lastname: Wehrman
authors.forename: L Y
authors.initials: LY
authors.lastname: Young
mesh_terms: D000595:Amino Acid Sequence; D000693:Anaerobiosis; D003001:Cloning, Molecular; D005609:Free Radicals; D005798:Genes, Bacterial; D005998:Glycine / Q000378:metabolism*; D006090:Gram-Negative Bacteria / Q000235:genetics* / Q000378:metabolism; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D013329:Structure-Activity Relationship; D014050:Toluene / Q000378:metabolism*
chemical_list: D005609:Free Radicals; D014050:Toluene; D005998:Glycine