A New UAG-Encoded Residue in the Structure of a Methanogen Methyltransferase

@article{Hao2002ANU,
  title={A New UAG-Encoded Residue in the Structure of a Methanogen Methyltransferase},
  author={Bing Hao and Weimin Gong and Tsuneo K Ferguson and Carey M. James and Joseph Adrian Krzycki and Michael K. Chan},
  journal={Science},
  year={2002},
  volume={296},
  pages={1462 - 1466}
}
Genes encoding methanogenic methylamine methyltransferases all contain an in-frame amber (UAG) codon that is read through during translation. We have identified the UAG-encoded residue in a 1.55 angstrom resolution structure of the Methanosarcina barkerimonomethylamine methyltransferase (MtmB). This structure reveals a homohexamer comprised of individual subunits with a TIM barrel fold. The electron density for the UAG-encoded residue is distinct from any of the 21 natural amino acids. Instead… 

Translation of the amber codon in methylamine methyltransferase genes of a methanogenic archaeon

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The Residue Mass of L-Pyrrolysine in Three Distinct Methylamine Methyltransferases*

Successful mass spectral characterization of naturally occurring pyrrolysine and the first demonstration of the amber-encoded residue in proteins other than MtmB are reported and suggests that MtbB and MttB may exploit the unusual electrophilicity of pyr rolysine during catalysis.

Functional context, biosynthesis, and genetic encoding of pyrrolysine.

Crystal structure of methylornithine synthase (PylB): insights into the pyrrolysine biosynthesis.

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Characterization of a Methanosarcina acetivorans mutant unable to translate UAG as pyrrolysine

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Hidden in Plain Sight: The Biosynthetic Source of Pyrrolysine Revealed

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    Chembiochem : a European journal of chemical biology
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An important clue as to the true identity of this elusive metabolite came from the observation that by exogenously supplying d-ornithine, but not amino acids 2–4, it was possible to significantly increase the level of the PylRS–tRNA-mediated UAG suppression in E. coli transformed with pylTSBCD.

Biosynthesis and charging of pyrrolysine, the 22nd genetically encoded amino acid.

It is found that this unprecedented lysine homologue is incorporated into several methyltransferases from archaebacteria, for example monomethylamine methyltransferase (MtmB; Figure 1) from Krzycki and colleagues.

Structure and reaction mechanism of pyrrolysine synthase (PylD).

The structural investigation and implementation on the reaction mechanism of the enzymes required for the biosynthesis of pyrrolysine are described and may open novel opportunities for the harnessing of the system for biotechnology purposes.
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