Harnett SP, et al. (1985) Mechanism of activation of phenylalanine and synthesis of P1, P4-bis(5'-adenosyl) tetraphosphate by yeast phenylalanyl-tRNA synthetase. Biochemistry 24(12):2908-15
Abstract: The activation of L-phenylalanine by yeast phenylalanyl-tRNA synthetase using adenosine 5'-[(S)-alpha-17O,alpha,alpha-18O2]triphosphate is shown to proceed with inversion of configuration at P alpha of ATP. This observation taken together with the lack of positional isotope exchange when adenosine 5'-[beta,beta-18O2]triphosphate is incubated with the enzyme in the absence of phenylalanine and in the presence of the competitive inhibitor phenylalaninol indicates that activation of phenylalanine occurs by a direct "in-line" adenylyl-transfer reaction. In the presence of Zn2+, yeast phenylalanyl-tRNA synthetase also catalyzes the phenylalanine-dependent hydrolysis of ATP to AMP and the synthesis of P1,P4-bis(5'-adenosyl) tetraphosphate (Ap4A). With adenosine 5'-[(S)-alpha-17O,alpha,alpha-18O2]triphosphate, the formation of AMP and Ap4A is shown to occur with inversion and retention of configuration, respectively. It is concluded that phenylalanyl adenylate is an intermediate in both processes, Zn2+ promoting AMP formation by hydrolytic cleavage of the C-O bond and Ap4A formation by displacement at phosphorus of phenylalanine by ATP.
| Status: Published | Type: Journal Article | PubMed ID: 3893531 |
Topics addressed in this paper
Number of different genes curated to this paper: 2
- To find other papers on a gene and topic, click on the colored ball in the appropriate box.
- displays other papers with information about that topic for that gene.
- displays other papers in SGD that are associated with that topic.
The topic is addressed in these papers but does not describe a specific gene or chromosomal feature.
- To go to the Locus page for a gene, click on the gene name.




