Identification of a Glutaminyl - tRNA Synthetase Mutation in Saccharomyces cerevisiae AARON
نویسنده
چکیده
Saccharomyces cerevisiae glutaminyl-tRNA synthetase mutants were isolated through systematic screening of tight Glnderivatives of a leaky glutamine auxotroph. These mutations define a single nuclear gene, GLN4. The gln4-1 mutation is specific for Gln-tRNA synthetase and shows a dosage effect in heterozygous diploids. The wild-type Gln-tRNA synthetase exhibits a Km for glutamine of 25 ,uM; the gln4mutation increases this value 20-fold. These observations strongly suggest .that GLN4 encodes the GlntRNA synthetase.
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