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Profiling of Methyltransferases and Other S-adenosyl-L-homocysteine-binding Proteins by Capture Compound Mass Spectrometry CCMS
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Profiling of Methyltransferases and Other S-adenosyl-L-homocysteine-binding Proteins by Capture Compound Mass Spectrometry CCMS

Published on: December 20, 2010

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As(III) S-adenosylmethionine methyltransferases and other arsenic binding proteins

A Abdul Ajees1, Barry P Rosen2

  • 1Department of Atomic and Molecular Physics, LG-01, Academic Block -5, MIT Campus, Manipal University, Manipal - 576 104, Karnataka, India.

Geomicrobiology Journal
|September 15, 2015
PubMed

Insights

Arsenic detoxification occurs via methylation by arsenic methyltransferase (AS3MT/ArsM) enzymes. This review examines the controversial methylation pathway and its implications for arsenic toxicity and carcinogenicity.

Area of Science:

  • Biochemistry
  • Environmental Toxicology
  • Molecular Biology

Background:

  • Arsenic detoxification primarily occurs through methylation catalyzed by arsenic methyltransferase (AS3MT/ArsM) enzymes.
  • AS3MT/ArsM enzymes are part of a larger methyltransferase superfamily with diverse physiological roles.
  • Over 5000 AS3MT/ArsM orthologues are documented in the NCBI database, predominantly in microbial organisms.

Purpose of the Study:

  • To review the biochemical mechanisms of arsenic methylation.
  • To examine the controversial pathway of arsenic methylation by AS3MT/ArsM enzymes.
  • To discuss the potential toxicity and carcinogenicity of methylated arsenic species.

Main Methods:

  • Literature review of existing research on AS3MT/ArsM enzymes.
  • Analysis of protein sequence data from the NCBI database.
  • Examination of various hypotheses regarding the arsenic methylation pathway.

Main Results:

  • Arsenic detoxification involves the conversion of inorganic arsenic (As(III)) into methylated forms by AS3MT/ArsM.
  • Methylated arsenic species may exhibit increased toxicity and carcinogenicity compared to inorganic arsenic.
  • The precise methylation pathway remains a subject of ongoing scientific debate.

Conclusions:

  • AS3MT/ArsM enzymes play a critical role in arsenic metabolism and detoxification across various organisms.
  • Understanding the methylation pathway is crucial for assessing the health risks associated with arsenic exposure.
  • Further research is needed to resolve the controversies surrounding the arsenic methylation pathway.

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