論文 - 詳細
| RRC ID | 29720 |
|---|---|
| 著者 | Gelfand DH, Steinberg RA. |
| タイトル | Escherichia coli mutants deficient in the aspartate and aromatic amino acid aminotransferases. |
| ジャーナル | J Bacteriol |
| Abstract |
Two new mutations are described which, together, eliminate essentially all the aminotransferase activity required for de novo biosynthesis of tyrosine, phenylalanine, and aspartic acid in a K-12 strain of Escherichia coli. One mutation, designated tyrB, lies at about 80 min on the E. coli map and inactivates the "tyrosine-repressible" tyrosine/phenylalanine aminotransferase. The second mutation, aspC, maps at about 20 min and inactivates a nonrespressible aspartate aminotransferase that also has activity on the aromatic amino acids. In ilvE- strains, which lack the branched-chain amino acid aminotransferase, the presence of either the tyrosine-repressible aminotransferase or the aspartate aminotransferase is sufficient for growth in the absence of exogenous tyrosine, phenylalanine, or aspartate; the tyrosine-repressible enzyme is also active in leucine biosynthesis. The ilvE gene product alone can reverse a phenylalanine requirement. Biochemical studies on extracts of strains carrying combinations of these aminotransferase mutations confirm the existence of two distinct enzymes with overlapping specificities for the alpha-keto acid analogues of tyrosine, phenylalanine, and aspartate. These enzymes can be distinguished by electrophoretic mobilities, by kinetic parameters using various substrates, and by a difference in tyrosine repressibility. In extracts of an ilvE- tyrB- aspC- triple mutant, no aminotransferase activity for the alpha-keto acids of tyrosine, phenylalanine, or aspartate could be detected. |
| 巻・号 | 130(1) |
| ページ | 429-40 |
| 公開日 | 1977-4-1 |
| DOI | 10.1128/jb.130.1.429-440.1977 |
| PMID | 15983 |
| PMC | PMC235221 |
| MeSH | Aspartate Aminotransferases / metabolism* Aspartic Acid / biosynthesis Chromosome Mapping Chromosomes, Bacterial Coliphages Escherichia coli / enzymology* Genes* Leucine / biosynthesis Mutation Phenylalanine / biosynthesis Transaminases / metabolism* Transduction, Genetic Tyrosine / biosynthesis Tyrosine Transaminase / metabolism* |
| IF | 3.006 |
| オルトメトリクス指標 |
オルトメトリクス指標項目
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| 最多言及媒体 | Patent(IFI CLAIMS) |
| 各媒体での言及数の合計 | 14 |
| 過去6か月間でのオルトメトリクス指標の変動値 | 0.0 |
| リソース情報 | |
| 原核生物(大腸菌) | ME8601 ME8600 ME8602 |