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Updated: May 8, 2026

In vitro tRNA Methylation Assay with the Entamoeba histolytica DNA and tRNA Methyltransferase Dnmt2 (Ehmeth) Enzyme
Published on: October 19, 2010
Characterization of a methyltransferase involved in herboxidiene biosynthesis
Dayu Yu1, Fuchao Xu, Shuwei Zhang
1Department of Applied Chemistry and Biological Engineering, College of Chemical Engineering, Northeast Dianli University, Jilin, Jilin 132012, China; Department of Biological Engineering, Utah State University, 4105 Old Main Hill, Logan, UT 84322, United States.
Abstract:
The herboxidiene biosynthetic gene cluster contains a regulatory gene and six biosynthetic genes that encode three polyketide synthases (HerB, HerC and HerD) and three tailoring enzymes (HerE, HerF and HerG). Through single crossover recombination, an integrative plasmid was inserted into the genome of Streptomyces chromofuscus ATCC 49982 between herE and herF, resulting in low-level expression of herF and the downstream herG. The mutant strain produced two new compounds, 18-deoxy-25-demethyl-herboxidiene and 25-demethyl-herboxidiene. HerF was expressed in Escherichia coli and biochemically characterized as the dedicated methyltransferase in herboxidiene biosynthesis. It prefers 25-demethyl-herboxidiene to 18-deoxy-25-demethyl-herboxidiene, suggesting that C-25 methylation is the last tailoring step.
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