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Updated: Mar 9, 2026

DNAzyme-dependent Analysis of rRNA 2’-O-Methylation
Published on: September 16, 2019
Functional and structural characterisation of a bacterial O-methyltransferase and factors determining
Jutta Siegrist1, Julia Netzer2, Silja Mordhorst1
1Institute of Pharmaceutical Sciences, Albert-Ludwigs-University Freiburg, Germany.
Abstract:
Mg2+ -dependent catechol-O-methyltransferases occur in animals as well as in bacteria, fungi and plants, often with a pronounced selectivity towards one of the substrate's hydroxyl groups. Here, we show that the bacterial MxSafC exhibits excellent regioselectivity for para as well as for meta methylation, depending on the substrate's characteristics. The crystal structure of MxSafC was solved in apo and in holo form. The structure complexed with a full set of substrates clearly illustrates the plasticity of the active site region. The awareness that a wide range of factors influences the regioselectivity will aid the further development of catechol-O-methyltransferases as well as other methyltransferases as selective and efficient biocatalysts for chemical synthesis.
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