FEBS Letters | |
Tyr‐426 of the Escherichia coli asparaginyl‐tRNA synthetase, an amino acid in a C‐terminal concerved motif, is involved in ATP binding | |
Härtlein, Michael1  Anselme, Jocelyne1  | |
[1] European Molecular Biology Labaratory, 38042 Grenoble Cedex, France | |
关键词: Sequence homology; Aminoacyl-tRNA synthetase; Site-directed mutagenesis; ATP binding; FPLC; fast protein liquid chromatography; k cat; catalytic rate constant; K m; Michaelis constant; SDS; sodium dodecyl sulphate; | |
DOI : 10.1016/0014-5793(91)80228-U | |
学科分类:生物化学/生物物理 | |
来源: John Wiley & Sons Ltd. | |
【 摘 要 】
Sequence comparisons of the E. Coli asparaginyl-tRNA synthetase (NRSEC) with aminoacyl-tRNA synthetase sequences of class II enzymes show significant homologies with aspartyl- and lysyl-tRNA synthetases. Three conserved regions were found, one of which is located in the C-terminal part of the NRSEC sequence. Site-directed mutagenesis was performed in this conserved region. A single point mutation Tyr-426→Ser results in a 15-fold increase in the K m for ATP, while all the other kinetic parameters remain unchanged. The replacement of this Tyr-426 by a Phe does not affect the behavior of the enzyme. These data indicate that Tyr-426 is part of the ATP binding site.
【 授权许可】
Unknown
【 预 览 】
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RO201912020294589ZK.pdf | 571KB | download |