322 / Biochemistry Aminoacyl-tRNA

Translation involves three stages initiation, elongation and termination. A brief summary of these processes is provided below. However, the first step in polypeptide synthesis, from intracellular amino acids, is the formation of aminoacyl-tRNA. This reaction is particularly important so that the biochemistry is discussed in some detail. In addition, it is also important in the regulation of the rate of translation (see below). 

Rodnina, M. V., Fricke, R., and Wintermeyer, W. (1994). Transient conformational states of aminoacyl-tRNA during ribosome binding catalyzed by elongation factor Tu. Biochemistry 33, 12267-12275. 

O. Piepenburg, T. Pape, J.A. Pleiss, W. Wintermeyer, O.C. Uhlenbeck, and M.V. Rodnina. 2000. Intact aminoacyl-tRNA is required to trigger GTP hydrolysis by elongation factor Tu on the ribosome Biochemistry 39 1734-1738. (PubMed)... 

On the whole, our present understanding of archaeal translation is far from being complete. There is a considerable dearth of information on such essential aspects of archaeal biochemistry as the structure and sequences of the aminoacyl-tRNA synthethases, the mechanism of polypeptide chain termination and release, the number and complexity of the initiation factors the possibility that the archaea may resemble eucarya in having a more complex set of initiation factors than exists in bacteria is, in fact, suggested by the identification in archaea of hypusine-containing proteins (see section 2.4). The development of efficient and accurate cell-free systems using natural messenger RNAs is an obvious priority in order to elucidate these points. 

AcK acetate kinase AcP acetyl phosphate AdK adenylate kinase AP A p ,pn-di(adenosine 5 -) n-phosphate ARS aminoacyl tRNA synthetase ATP, ADP, AMP adenosine 5 -tri-, di-, monophosphate ATP-u-S (Sp)-adenosine 5 -0-(l-thiotriphos-phate), ATP-y-S adenosine 5 -0-(3-thiotriphosphate) CK carbamyl kinase CP carbamyl phosphate CrK creatine kinase CTP, CDP, CMP cytidine 5 -tri-, di-, monophosphate dATP, dAMP deoxyadenosine 5 -tri-, monophosphate DNA deoxyribonucleic acid AG change in free energy GK glycerol kinase GTP, GDP, GMP guanosine 5 -tri-, di-, monophosphate HK hexokinase IUB International Union of Biochemistry MCP methoxycarbonyl phosphate NTP, NDP, NMP nucleoside 5 -tri-, di-, monophosphate PC phosphocreatine PEP phosphoenol pyruvate P orthophosphate PK pyruvate kinase P polyphosphate PnK poly-... 

J.D. Bain, E.S. Diala, C.G. Glabe, D.A. Wacker, M.H. Lyttle, T.A. Dix, A.R. Chamberlin, Site-specific incorporation of nonnatural residues during in vitro protein biosynthesis with semi-synthetic aminoacyl-tRNAs, Biochemistry 1991, 30, 5411-5421. 

Friederich, M. W., and Hagerman, P. J. (1997). The angle between the anticodon and aminoacyl acceptor stems of yeast tRNA(Phe) is strongly modulated by magnesium ions. Biochemistry 36, 6090—6099. 

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