PubMed Health⌕ Search

PubMed · 12121639

Genetic code: introducing pyrrolysine.

Abstract

Monomethylamine methyltransferase of the archaebacterium Methanosarcina barkeri contains a novel amino acid, pyrrolysine, encoded by the termination codon UAG. Initial studies suggest that pyrrolysine may be co-translationally inserted during protein synthesis, probably by a mechanism analogous to that operating during selenocysteine incorporation.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Michael Ibba, Dieter Söll. 2002-07-09. Genetic code: introducing pyrrolysine.. https://doi.org/10.1016/s0960-9822(02)00947-8

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

Molecular network and functional implications of macromolecular tRNA synthetase complex.

Understanding the complex network and multi-functionality of proteins is one of the main objectives of post-genome research. Aminoacyl-tRNA synthetases (ARSs) are the family of enzymes that are essential for cellular protein synthesis and viability that catalyze the attachment of specific amino acids to their cognate tRNAs. However, a lot of evidence has shown that these enzymes are multi-functional proteins that are involved in diverse cellular processes, such as tRNA processing, RNA splicing and trafficking, rRNA synthesis, apoptosis, angiogenesis, and inflammation. In addition, mammalian ARSs form a macromolecular complex with three auxiliary factors or with the elongation factor complex. Although the functional meaning and physiological significance of these complexes are poorly understood, recent data on the molecular interactions among the components for the multi-ARS complex are beginning to provide insights into the structural organization and cellular functions. In this review, the molecular mechanism for the assembly and functional implications of the multi-ARS complex will be discussed.

Amino Acyl-tRNA Synthetases↗

Generation of a bacterium with a 21 amino acid genetic code.

We have generated a completely autonomous bacterium with a 21 amino acid genetic code. This bacterium can biosynthesize a nonstandard amino acid from basic carbon sources and incorporate this amino acid into proteins in response to the amber nonsense codon. The biosynthetic pathway for the amino acid p-aminophenylalanine (pAF) as well as a unique pAF synthetase and cognate tRNA were added to Escherichia coli. Denaturing gel electrophoresis and mass spectrometric analysis show that pAF is incorporated into myoglobin with fidelity and efficiency rivaling those of the common 20 amino acids. This and other such organisms may provide an opportunity to examine the evolutionary consequences of adding new amino acids to the genetic repertoire, as well as generate proteins with new or enhanced biological functions.

Amino Acyl-tRNA Synthetases↗