Functional characterization of the D-Tyr-tRNATyr deacylase from Escherichia coli.
The yihZ gene of Escherichia coli is shown to produce a deacylase activity capable of recycling misaminoacylated D-Tyr-tRNATyr. The reaction is specific and, under optimal in vitro conditions, proceeds at a rate of 6 s-1 with a Km value for the substrate equal to 1 microM. Cell growth is sensitive to interruption of the yihZ gene if D-tyrosine is added to minimal culture medium. Toxicity of exogenous D-tyrosine is exacerbated if, in addition to the disruption of yihZ, the gene of D-amino acid dehydrogenase (dadA) is also inactivated. Orthologs of the yihZ gene occur in many, but not all, bacteria. In support of the idea of a general role of the D-Tyr-tRNATyr deacylase function in the detoxification of cells, similar genes can be recognized in Saccharomyces cerevisiae, Caenorhabditis elegans, Arabidopsis thaliana, mouse, and man.
Soutourina
J
J
Laboratoire de Biochimie, Unité Mixte de Recherche No. 7654, CNRS-Ecole Polytechnique, 91128 Palaiseau Cedex, France.
Plateau
P
P
Delort
F
F
Peirotes
A
A
Blanquet
S
S
D019881:Aminoacyltransferases / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D002384:Catalysis; D003001:Cloning, Molecular; D004269:DNA, Bacterial / Q000737:chemistry; D004926:Escherichia coli / Q000201:enzymology* / Q000235:genetics; D015723:Gene Library; D006801:Humans; D008297:Male; D051379:Mice; D016366:Open Reading Frames; D016133:Polymerase Chain Reaction; D012365:RNA, Transfer, Tyr / Q000378:metabolism*; D015183:Restriction Mapping
D004269:DNA, Bacterial; D012365:RNA, Transfer, Tyr; D019881:Aminoacyltransferases; C120167:D-tyrosine tRNA(Tyr) deacylase