In the present study, two novel phenolic UDP glycosyltransferases (P-UGTs), UGT58A1 and UGT59A1, which can transfer sugar moieties from active donors to phenolic acceptors to generate corresponding glycosides, were identified in the fungal kingdom. UGT58A1 (from Absidia coerulea) and UGT59A1 (from Rhizopus japonicas) share a low degree of homology with known UGTs from animals, plants, bacteria, and viruses. These two P-UGTs are membrane-bound proteins with an N-terminal signal peptide and a transmembrane domain at the C terminus. Recombinant UGT58A1 and UGT59A1 are able to regioselectively and stereoselectively glycosylate a variety of phenolic aglycones to generate the corresponding glycosides. Phylogenetic analysis revealed the novelty of UGT58A1 and UGT59A1 in primary sequences in that they are distantly related to other UGTs and form a totally new evolutionary branch. Moreover, UGT58A1 and UGT59A1 represent the first members of the UGT58 and UGT59 families, respectively. Homology modeling and mutational analysis implied the sugar donor binding sites and key catalytic sites, which provided insights into the catalytic mechanism of UGT58A1. These results not only provide an efficient enzymatic tool for the synthesis of bioactive glycosides but also create a starting point for the identification of P-UGTs from fungi at the molecular level.
glycosylation, fungi, UDP glycosyltransferases, phenolics, phylogenetics
NCBI PubMed ID: 28159792Publication DOI: 10.1128/AEM.03103-16Journal NLM ID: 7605801Publisher: American Society for Microbiology
Correspondence: jgdai@imm.ac.cn
Institutions: State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
Methods: 13C NMR, 1H NMR, DNA techniques, ESI-MS, biological assays, extraction, cell growth, HMBC, COSY, HSQC, HPLC-UV
Found