Format

Send to

Choose Destination
See comment in PubMed Commons below
Trends Genet. 2006 Jul;22(7):357-60. Epub 2006 May 19.

Is there a twenty third amino acid in the genetic code?

Author information

1
Department of Biochemistry, University of Nebraska, Lincoln, NE 68588, USA.

Abstract

The universal genetic code includes 20 common amino acids. In addition, selenocysteine (Sec) and pyrrolysine (Pyl), known as the twenty first and twenty second amino acids, are encoded by UGA and UAG, respectively, which are the codons that usually function as stop signals. The discovery of Sec and Pyl suggested that the genetic code could be further expanded by reprogramming stop codons. To search for the putative twenty third amino acid, we employed various tRNA identification programs that scanned 16 archaeal and 130 bacterial genomes for tRNAs with anticodons corresponding to the three stop signals. Our data suggest that the occurrence of additional amino acids that are widely distributed and genetically encoded is unlikely.

PMID:
16713651
DOI:
10.1016/j.tig.2006.05.002
[Indexed for MEDLINE]
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Elsevier Science
    Loading ...
    Support Center