Biocompatible, small-sized but well-dispersed gold nanoparticles (Au NPs) remain a major challenge for their synthesis. Here a convenient solution impregnation technique is developed to prepare such Au NPs under the r...Biocompatible, small-sized but well-dispersed gold nanoparticles (Au NPs) remain a major challenge for their synthesis. Here a convenient solution impregnation technique is developed to prepare such Au NPs under the regulation of degummed silk fibroin fibers (SFFs) extracted from Bombyx mori cocoons. SFFs play multiple roles in the formation of Au NPs such as reactive substrate to capture AuCl4^- ions by the chelation of -C = 0, reducing agent for Au(0) by the reduction of -OH , and modifiers to render biocompatible Au NPs by some functional groups and biomolecules. The as-prepared Au NPs with a size of 7-10 nm are embedded in the solid SFF substrate, and can disperse well in the liquid system by the disintegration of SFFs into silk fibroin (SF) in a certain CaCl2 solution. The biocompatible Au NPs exhibit uniform small size and distribute stably in both solid and solution states, which have distinctive properties and functional advantages, and bring great convenience to their storage and transportation.展开更多
Epimedium pubescens Maxim.is a well-known traditional Chinese medicinal herb with flavonol glycosides as the major pharmaceutically active compounds.UDP-glycosyltransferases(UGTs)are a group of enzymes responsible for...Epimedium pubescens Maxim.is a well-known traditional Chinese medicinal herb with flavonol glycosides as the major pharmaceutically active compounds.UDP-glycosyltransferases(UGTs)are a group of enzymes responsible for the glycosylation of flavonoid glycosides.In this study,a genome-wide analysis was performed to identify UGT family genes in E.pubescens.As a result,a total of 339 putative UGT genes were identified,which represents the largest UGT gene family known thus far,implying a significant expansion of the UGT gene family in E.pubescens.All EpUGTs were unevenly distributed across six chromosomes,and they were classified into 17 major groups.The expression profiles showed that UGT genes were differentially expressed in roots,leaves,flowers,shoots and fruits.In particular,several EpUGTs were highly induced by high light intensity,which was consistent with the accumulation level of bioactive flavonoids in E.pubescens.Six UGT79 genes that were preferentially expressed in roots or leaves were successfully expressed in E.coli,and only the recombinant EpGT60 protein was found to be active toward 8-prenylkaempferol and icaritin to produce the key bioactive compounds baohuoside II and baohuoside I.The optimal temperature,pH,k_(m) and V_(max) were determined for the recombinant EpGT60 protein.In addition,expression of recombinant EpGT60 in E.coli cell culture led to successful production of baohuoside II when fed 8-prenylkaempferol.Our study provides a foundation for further functional characterization of UGT genes in E.pubescens and provides key candidate genes for bioengineering bioactive flavonoids in E.pubescens.展开更多
基金the National Key Research and Development Program of China (Grant No. 2017YFB1201005)the National Natural Science Foundation of China (Grant Nos. 51572169 and 51672175)the Shanghai Science and Technology Committee (Grant Nos. 17ZR1441400 and 18JC1410500).
文摘Biocompatible, small-sized but well-dispersed gold nanoparticles (Au NPs) remain a major challenge for their synthesis. Here a convenient solution impregnation technique is developed to prepare such Au NPs under the regulation of degummed silk fibroin fibers (SFFs) extracted from Bombyx mori cocoons. SFFs play multiple roles in the formation of Au NPs such as reactive substrate to capture AuCl4^- ions by the chelation of -C = 0, reducing agent for Au(0) by the reduction of -OH , and modifiers to render biocompatible Au NPs by some functional groups and biomolecules. The as-prepared Au NPs with a size of 7-10 nm are embedded in the solid SFF substrate, and can disperse well in the liquid system by the disintegration of SFFs into silk fibroin (SF) in a certain CaCl2 solution. The biocompatible Au NPs exhibit uniform small size and distribute stably in both solid and solution states, which have distinctive properties and functional advantages, and bring great convenience to their storage and transportation.
基金supported by the National Natural Science Foundation of China(51971133,51902200,52071213,32000981 and 52072241)Shanghai Science and Technology Committee(18JC1410500,19ZR1425300 and 19ZR1425100)+2 种基金the National High-Level Talent Program for Young Scholars,Shenzhen Science and Technology Research Funding(JCYJ20190806170011328)China National Postdoctoral Program for Innovative Talents(BX20190352)Guangdong Province Fundamental Research Funds(2019A1515111209).
基金This work was supported by grants from the CAMS Innovation Fund for Medical Sciences(CIFMS)(2021-I2M-1-031 and 2017-I2M-3-013)the National Natural Science Foundation of China(31570306 and 81473302).
文摘Epimedium pubescens Maxim.is a well-known traditional Chinese medicinal herb with flavonol glycosides as the major pharmaceutically active compounds.UDP-glycosyltransferases(UGTs)are a group of enzymes responsible for the glycosylation of flavonoid glycosides.In this study,a genome-wide analysis was performed to identify UGT family genes in E.pubescens.As a result,a total of 339 putative UGT genes were identified,which represents the largest UGT gene family known thus far,implying a significant expansion of the UGT gene family in E.pubescens.All EpUGTs were unevenly distributed across six chromosomes,and they were classified into 17 major groups.The expression profiles showed that UGT genes were differentially expressed in roots,leaves,flowers,shoots and fruits.In particular,several EpUGTs were highly induced by high light intensity,which was consistent with the accumulation level of bioactive flavonoids in E.pubescens.Six UGT79 genes that were preferentially expressed in roots or leaves were successfully expressed in E.coli,and only the recombinant EpGT60 protein was found to be active toward 8-prenylkaempferol and icaritin to produce the key bioactive compounds baohuoside II and baohuoside I.The optimal temperature,pH,k_(m) and V_(max) were determined for the recombinant EpGT60 protein.In addition,expression of recombinant EpGT60 in E.coli cell culture led to successful production of baohuoside II when fed 8-prenylkaempferol.Our study provides a foundation for further functional characterization of UGT genes in E.pubescens and provides key candidate genes for bioengineering bioactive flavonoids in E.pubescens.
