Structure-guided analysis reveals nine sequence motifs conserved among DNA amino-methyltransferases, and suggests a catalytic mechanism for these enzymes

Malone, T., Blumenthal, R. M., Cheng, X. (November 1995) Structure-guided analysis reveals nine sequence motifs conserved among DNA amino-methyltransferases, and suggests a catalytic mechanism for these enzymes. J Mol Biol, 253 (4). pp. 618-32. ISSN 0022-2836 (Print)

URL: http://www.ncbi.nlm.nih.gov/pubmed/7473738
DOI: 10.1006/jmbi.1995.0577

Abstract

Previous X-ray crystallographic studies have revealed that the catalytic domain of a DNA methyltransferase (Mtase) generating C5-methylcytosine bears a striking structural similarity to that of a Mtase generating N6-methyladenine. Guided by this common structure, we performed a multiple sequence alignment of 42 amino-Mtases (N6-adenine and N4-cytosine). This comparison revealed nine conserved motifs, corresponding to the motifs I to VIII and X previously defined in C5-cytosine Mtases. The amino and C5-cytosine Mtases thus appear to be more closely related than has been appreciated. The amino Mtases could be divided into three groups, based on the sequential order of motifs, and this variation in order may explain why only two motifs were previously recognized in the amino Mtases. The Mtases grouped in this way show several other group-specific properties, including differences in amino acid sequence, molecular mass and DNA sequence specificity. Surprisingly, the N4-cytosine and N6-adenine Mtases do not form separate groups. These results have implications for the catalytic mechanisms, evolution and diversification of this family of enzymes. Furthermore, a comparative analysis of the S-adenosyl-L-methionine and adenine/cytosine binding pockets suggests that, structurally and functionally, they are remarkably similar to one another.

Item Type: Paper
Uncontrolled Keywords: Amino Acid Sequence Comparative Study Conserved Sequence Cytosine/metabolism Evolution, Molecular Methyltransferases/ chemistry/metabolism Molecular Sequence Data Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S. Research Support, U.S. Gov't, P.H.S. S-Adenosylmethionine Sequence Alignment
Subjects: bioinformatics > genomics and proteomics > design > amino acid design
bioinformatics > genomics and proteomics > genetics & nucleic acid processing > protein structure, function, modification > protein types > enzymes
bioinformatics > genomics and proteomics > genetics & nucleic acid processing > protein structure, function, modification > protein types > methyltransferase
CSHL Authors:
Communities: CSHL labs
Depositing User: Jessica Koos
Date: 3 November 1995
Date Deposited: 08 Aug 2014 19:48
Last Modified: 08 Aug 2014 19:48
Related URLs:
URI: http://repository.cshl.edu/id/eprint/30620

Actions (login required)

Administrator's edit/view item Administrator's edit/view item
CSHL HomeAbout CSHLResearchEducationNews & FeaturesCampus & Public EventsCareersGiving