Display Settings:

Format

Send to:

Choose Destination
See comment in PubMed Commons below
Genome Res. 2004 Nov;14(11):2279-86. Epub 2004 Oct 12.

Codon usage bias from tRNA's point of view: redundancy, specialization, and efficient decoding for translation optimization.

Author information

  • Unité Génétique des Génomes Bactériens, Institut Pasteur, 75724 Paris Cedex 15, France. erocha@pasteur.fr

Erratum in

  • Genome Res. 2004 Dec;14(12):2510.

Abstract

The selection-mutation-drift theory of codon usage plays a major role in the theory of molecular evolution by explaining the co-evolution of codon usage bias and tRNA content in the framework of translation optimization. Because most studies have focused only on codon usage, we analyzed the tRNA gene pool of 102 bacterial species. We show that as minimal generation times get shorter, the genomes contain more tRNA genes, but fewer anticodon species. Surprisingly, despite the wide G+C variation of bacterial genomes these anticodons are the same in most genomes. This suggests an optimization of the translation machinery to use a small subset of optimal codons and anticodons in fast-growing bacteria and in highly expressed genes. As a result, the overrepresented codons in highly expressed genes tend to be the same in very different genomes to match the same most-frequent anticodons. This is particularly important in fast-growing bacteria, which have higher codon usage bias in these genes. Three models were tested to understand the choice of codons recognized by the same anticodons, all providing significant fit, but under different classes of genes and genomes. Thus, co-evolution of tRNA gene composition and codon usage bias in genomes seen from tRNA's point of view agrees with the selection-mutation-drift theory. However, it suggests a much more universal trend in the evolution of anticodon and codon choice than previously thought. It also provides new evidence that a selective force for the optimization of the translation machinery is the maximization of growth.

PMID:
15479947
[PubMed - indexed for MEDLINE]
PMCID:
PMC525687
Free PMC Article

Images from this publication.See all images (2)Free text

Figure 1.
Figure 2.
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for HighWire Icon for PubMed Central
    Loading ...
    Write to the Help Desk