【报告题目1】Glycosylation of Small Molecule Using Flexible Glycosyltransferase
【报告人】 Prof. Jae Kyung Sohng
Department of Pharmaceutical Engineering
Sun Moon University, Korea
A UDP-glycosyltransferase, YjiC from Bacillus licheniformis DSM13 was exploited for the glycosylation of a number of small molecules. The in-vitro glycosyltransferase assay using YjiC lead to the production of multiple glucosides of polyhydroxyl groups containing aromatic/phenolic as well as aliphatic small molecules exhibiting wide substrate flexibility of the enzyme. We tested the activity of the enzyme with different classes of flavonoids, isoflavonoids, stilbenes, xanthonoids, curcuminoids, benzoates, salicylic acids, and other available compounds in the laboratory. Moreover, we have found the wide donor substrate flexibility of YjiC with different NDP-sugars (UDP-sugars, TDP-sugars, GDP-sugars) transferring a range of modified sugars including L- and D-sugars to the selected acceptors which guide to the production of a number of novel derivatives of natural products. But, it is found that YjiC could transfer only at limited positions of the polyhydroxylated compounds with diverse NDP-sugar donors. We further successfully applied YjiC for the in-vivo biotransformation of different flavonoids using engineered E. coli in large scale fermentor to produce glucosylated derivatives. In conclusion, it is found that YjiC has wide donor as well as acceptor substrates flexibility with high catalytic activity. The further exploitation of such glycosyltransferases could help to efficient production of glycosylated derivatives of natural products which might have potential therapeutic as well as cosmetic applications. However, it is important to carry out enzyme’s structure elucidation and mutagenesis studies to engineer enzyme to develop YjiC as regiospecific glycosyltransferase for the target compound production.
【报告题目2】Chemical Synthetic Biology: Deciphering and Engineering the Biosynthetic Pathways of Natural Products
【报告人】 Prof. Yeo Joon Yoon
Department of Chemistry and Nano Science
Ewha Womans University, Republic of Korea
We are mainly focusing on characterization of the biosynthetic pathway and creating the structural diversity of natural products including polyketides and aminoglycosides through the combinatorial biosynthetic approach. Synthetic biology is a new area of biological research that combines science and engineering in order to design and build novel biological functions and systems. Combinatorial biosynthesis is one area of synthetic biology for the generation of novel natural products. The basic concept of combinatorial biosynthesis is combining metabolic pathways in different organisms on a genetic level. The synthetic biological approaches combined with combinatorial biosynthesis will allow us “the biological total synthesis of natural products”, which will eventually lead to the unlimited structural diversification of natural product, drug discovery, and mass production. Some recent examples for this chemical synthetic biology approaches will be presented.