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Updated: Sep 28, 2026

Sequence-specific Labeling of Nucleic Acids and Proteins with Methyltransferases and Cofactor Analogues
Published on: November 22, 2014
SAM (dependent) I AM: the S-adenosylmethionine-dependent methyltransferase fold
Jennifer L Martin1, Fiona M McMillan
1Centre for Drug Design and Development, and Special Research Centre for Functional and Applied Genomics, Institute for Molecular Bioscience, University of Queensland, Brisbane QLD 4072, Australia. J.Martin@imb.uq.edu.au
Abstract:
The S-adenosylmethionine-dependent methyltransferase enzymes share little sequence identity, but incorporate a highly conserved structural fold. Surprisingly, residues that bind the common cofactor are poorly conserved, although the binding site is localised to the same region of the fold. The substrate-binding region of the fold varies enormously. Over the past two years, there has been a significant increase in the number of structures that are known to incorporate this fold, including several uncharacterized proteins and two proteins that lack methyltransferase activity.
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