Haocheng Qianzhu

  • Citations Per Year
Learn More
S-Adenosylmethionine (SAM) is one of the most common co-substrates in enzyme-catalyzed methylation reactions. Most SAM-dependent reactions proceed through an SN 2 mechanism, whereas a subset of them involves radical intermediates for methylating non-nucleophilic substrates. Herein, we report the characterization and mechanistic investigation of NosN, a(More)
The radical SAM tryptophan (Trp) lyase NosL involved in nosiheptide biosynthesis catalyzes two parallel reactions, converting l-Trp to 3-methyl-2-indolic acid (MIA) and to dehydroglycine and 3-methylindole, respectively. The two parallel reactions diverge from a nitrogen-centered tryptophanyl radical intermediate. Here we report an investigation on the(More)
Cobalamins comprise a group of cobalt-containing organometallic cofactors that play important roles in cellular metabolism. Although many cobalamin-dependent methyltransferases (e.g., methionine synthase MetH) have been extensively studied, a new group of methyltransferases that are cobalamin-dependent and utilize radical chemistry in catalysis is just(More)
NosN is a class C radical S-adenosylmethionine (SAM) methyltransferase (RSMT) involved in the biosynthesis of nosiheptide, a clinically interesting thiopeptide antibiotic produced by Streptomyces actuosus. NosN employs an unprecedented catalytic mechanism, in which SAM is converted to 5'-methylthioadenosine (MTA) as a direct methyl donor. In this study, we(More)
  • 1