title: Molecular characterization of the gene coding for threonine dehydrogenase in Xanthomonas campestris.
abstract: The Xanthomonas campestris pv. campestris 17 gene tdh, which codes for the threonine dehydrogenase (TDH), was cloned and sequenced. The deduced gene product, a polypeptide consisting of 340 amino acids (Mr = 37,048), has 63.5% identity to the E. coli TDH in amino acid sequence and shares residue conservation with the alcohol/polyol dehydrogenases from different organisms. TDH activity was not detectable in the tdh mutant constructed by gene replacement; however, the enzyme activity in the mutant complemented in trans by a plasmid containing the complete tdh sequence was increased by 15 folds over Xc17. Northern blot analysis detected an mRNA with a size similar to that of the Xc17 tdh coding region, suggesting that the tdh gene-containing transcript may be monocistronic.
authors.affiliation: Institute of Molecular Biology, National Chung Hsing University, Taichung, Taiwan, Republic of China.
authors.forename: Y S
authors.initials: YS
authors.lastname: Liu
authors.forename: Y H
authors.initials: YH
authors.lastname: Tseng
authors.forename: J W
authors.initials: JW
authors.lastname: Lin
authors.forename: S F
authors.initials: SF
authors.lastname: Weng
mesh_terms: D000429:Alcohol Oxidoreductases / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D000595:Amino Acid Sequence; D001483:Base Sequence; D015152:Blotting, Northern; D003001:Cloning, Molecular; D017124:Conserved Sequence; D004926:Escherichia coli / Q000235:genetics; D005798:Genes, Bacterial; D008969:Molecular Sequence Data; D016296:Mutagenesis; D009876:Operon; D012329:RNA, Bacterial / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D013401:Sugar Alcohol Dehydrogenases / Q000737:chemistry; D014158:Transcription, Genetic; D016959:Xanthomonas campestris / Q000201:enzymology / Q000235:genetics*
chemical_list: D012329:RNA, Bacterial; D012333:RNA, Messenger; D000429:Alcohol Oxidoreductases; D013401:Sugar Alcohol Dehydrogenases; C023159:L-threonine 3-dehydrogenase