Page 179 - Academic Press Encyclopedia of Physical Science and Technology 3rd BioChemistry

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Encyclopedia of Physical Science and Technology EN013D-617 July 27, 2001 11:42

Protein Synthesis

Paul Schimmel Rebecca W. Alexander
Scripps Research Institute Wake Forest University

I. Information Transfer IX. Molecular Mimicry by Translational Factors
and the Genetic Code X. Translational Accuracy
II. Transfer RNAs XI. The Ribosome
III. Aminoacyl–tRNA Synthetases XII. Inhibitors of Protein Synthesis
IV. An Overview of Translation XIII. Post-Translational Modifications
V. Translation Initiation XIV. Mitochondrial Protein Synthesis
VI. Elongation XV. Nonribosomal Peptide Synthesis
VII. Termination XVI. Protein Synthesis and the RNA World
VIII. Ribosome Recycling

GLOSSARY PROTEINS are polymers of amino acids joined by pep-
tide bonds (proteins are therefore also known as polypep-
Aminoacylation Attachment of an amino acid to its cog- tides). The number and order of the amino acids contained
nate (matching) transfer RNA (tRNA), catalyzed by the in a particular protein are prescribed by the DNA sequence
cognate aminoacyl–tRNA synthetase (AARS). of that protein’s gene. The mechanism by which a ge-
Anticodon The trinucleotide sequence at the end of one netic message is translated from its nucleic acid form to
arm of tRNA that base pairs with a complementary its polypeptide product is protein synthesis. Translation
messenger RNA (mRNA) codon. occurs at the ribosome, an RNA–protein complex often
Codon The trinucleotide sequence of an mRNA that called the protein factory of the cell.
specifies which amino acid will be inserted into a
protein.
Genetic code The set of rules that specify codon-amino I. INFORMATION TRANSFER
acid correspondence. AND THE GENETIC CODE
Translation Synthesis of a protein according to its
mRNA sequence. Many cellular components play a role in protein synthesis
Watson–Crick base pair Hydrogen bond partners in (Fig. 1). Even in relatively simple bacteria, translation
RNA or DNA. Adenine is the Watson–Crick partner of a single polypeptide from its genetic message requires
to uracil (or thymine in DNA); guanine pairs with dozens of participants—proteins, RNAs, and nucleo-
cytosine. tides—working together as carriers, catalysts, energy

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