Guangde Jiang1, Yi Zhang1, Magan M Powell1, Sarah M Hylton1, Nicholas W Hiller1, Rosemary Loria2, Yousong Ding1. 1. Department of Medicinal Chemistry, Center for Natural Products, Drug Discovery and Development, University of Florida, Gainesville, FL, 32610, USA. 2. Department of Plant Pathology, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL, 32611, USA.
Abstract
Cytochrome P450 enzymes generally functionalize inert C-H bonds, and thus, they are important biocatalysts for chemical synthesis. However, enzymes that catalyze both aliphatic and aromatic hydroxylation in the same biotransformation process have rarely been reported. A recent biochemical study demonstrated the P450 TxtC for the biosynthesis of herbicidal thaxtomins as the first example of this unique type of enzyme. Herein, the detailed characterization of substrate requirements and biocatalytic applications of TxtC are reported. The results reveal the importance of N-methylation of the thaxtomin diketopiperazine (DKP) core on enzyme reactions and demonstrate the tolerance of the enzyme to modifications on the indole and phenyl moieties of its substrates. Furthermore, hydroxylated, methylated, aromatic DKPs are synthesized through a biocatalytic route comprising TxtC and the promiscuous N-methyltransferase Amir_4628; thus providing a basis for the broad application of this unique P450.
Cytochrome P450 enzymes generally functionalize inert C-H bonds, and thus, they are important biocatalysts for chemical synthesis. However, enzymes that catalyze both aliphatic and aromatic hydroxylation in the same biotransformation process have rarely been reported. A recent biochemical study demonstrated the P450 TxtC for the biosynthesis of herbicidal n class="Chemical">thaxtomins as the first example of this unique type of enzyme. Herein, the detailed characterization of substrate requirements and biocatalytic applications of TxtC are reported. The results reveal the importance of N-methylation of the thaxtomin diketopiperazine (DKP) core on enzyme reactions and demonstrate the tolerance of the enzyme to modifications on the indole and phenyl moieties of its substrates. Furthermore, hydroxylated, methylated, aromatic DKPs are synthesized through a biocatalytic route comprising TxtC and the promiscuous N-methyltransferase Amir_4628; thus providing a basis for the broad application of this unique P450.
Authors: Lona M Alkhalaf; Sarah M Barry; Dean Rea; Angelo Gallo; Daniel Griffiths; Józef R Lewandowski; Vilmos Fulop; Gregory L Challis Journal: J Am Chem Soc Date: 2018-12-19 Impact factor: 15.419