Molecular characterization of the gene coding for threonine dehydrogenase in Xanthomonas campestris.
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.
Liu
Y S
YS
Institute of Molecular Biology, National Chung Hsing University, Taichung, Taiwan, Republic of China.
Tseng
Y H
YH
Lin
J W
JW
Weng
S F
SF
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*
D012329:RNA, Bacterial; D012333:RNA, Messenger; D000429:Alcohol Oxidoreductases; D013401:Sugar Alcohol Dehydrogenases; C023159:L-threonine 3-dehydrogenase