Selenocysteine



Selenocysteine
IUPAC name L-Selenocysteine
Identifiers
CAS number 10236-58-5
SMILES N[C@@H](C[SeH])C(O)=O
Properties
Molecular formula C3H7NO2Se
Molar mass 168.053 g/mol
Except where noted otherwise, data are given for
materials in their standard state
(at 25 °C, 100 kPa)
Infobox disclaimer and references

Selenocysteine is an hydrogenases).

Nomenclature

The joint nomenclature committee of the IUPAC/IUBMB has officially recommended the three-letter symbol Sec and the one-letter symbol U for selenocysteine.[1]

Structure

Selenocysteine has a structure similar to selenoproteins.

Biology

Unlike other amino acids present in biological 3' untranslated region (3' UTR) of the mRNA, and can direct multiple UGA codons to encode selenocysteine residues. When cells are grown in the absence of selenium, translation of selenoproteins terminates at the UGA codon, resulting in a truncated, nonfunctional enzyme.

Like the other amino acids used by cells, selenocysteine has a specialized 5' UTR.

See also

  • Sodium selenite
  • Pyrrolysine, another amino acid not in the basic set of 20.

References

  1. ^ IUPAC-IUBMB Joint Commission on Biochemical Nomenclature (JCBN) and Nomenclature Committee of IUBMB (NC-IUBMB) (1999). "Newsletter 1999" (reprint, with permission). European Journal of Biochemistry 264 (2): 607-609. doi:10.1046/j.1432-1327.1999.news99.x.

Further reading

  • F. Zinoni, A. Birkmann, T. C. Stadtman and A. Bock (1986). "Nucleotide Sequence and Expression of the Selenocysteine-Containing Polypeptide of Formate Dehydrogenase (Formate-hydrogen-lyase-Linked) from Escherichia coli". PNAS 83 (13): 4650-4654. PMID 2941757.
  • F. Zinoni, A. Birkmann, W. Leinfelder and A. Bock (1987). "Cotranslational Insertion of Selenocysteine into Formate Dehydrogenase from Escherichia coli Directed by a UGA Codon". PNAS 84 (10): 3156-3160.
  • Boyce E. Cone, Rafael Martin Del Rio, Joe Nathan Davis, and Thressa C. Stadtman (1976). "Chemical Characterization of the Selenoprotein Component of Clostridial Glycine Reductase: Identification of Selenocysteine as the Organoselenium Moiety". PNAS 73 (8): 2659-2663. doi:10.1146/annurev.bi.65.070196.000503.
 
This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Selenocysteine". A list of authors is available in Wikipedia.