Burkholderia glumae ToxA Is a Dual-Specificity Methyltransferase That Catalyzes the Last Two Steps of Toxoflavin Biosynthesis.

  title={Burkholderia glumae ToxA Is a Dual-Specificity Methyltransferase That Catalyzes the Last Two Steps of Toxoflavin Biosynthesis.},
  author={Michael K Fenwick and Benjamin Philmus and Tadhg P. Begley and Steven E. Ealick},
  volume={55 19},
Toxoflavin is a major virulence factor of the rice pathogen Burkholderia glumae. The tox operon of B. glumae contains five putative toxoflavin biosynthetic genes toxABCDE. ToxA is a predicted S-adenosylmethionine-dependent methyltransferase, and toxA knockouts of B. glumae are less virulent in plant infection models. In this study, we show that ToxA performs two consecutive methylations to convert the putative azapteridine intermediate, 1,6-didemethyltoxoflavin, to toxoflavin. In addition, we… 

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