We have developed an expedient approach,＂HOPE＂（hybrid orthogonal protocol with ease） strategy for the synthesis of peptidyl N-alkylamides.This new strategy was characterized by following points：incorporating Boc ...We have developed an expedient approach,＂HOPE＂（hybrid orthogonal protocol with ease） strategy for the synthesis of peptidyl N-alkylamides.This new strategy was characterized by following points：incorporating Boc and Fmoc protocols together on Merrifield resin,removal of SPG（side-chain protecting groups） without the damage of linker structure on the resin,and the ammonolysis of linker as the last step could achieve the introducing N-alkylamide structure into C-terminal and releasing product from resin-support simultaneously.In present work,eight peptidylamides with different alkylsubstitution at C-terminal were conveniently synthesized by HOPE strategy.展开更多
The efficiency of TFMSA as a cleaving reagent for peptidyl resin(I-VIII)was evaluated by quantitative ninhydrin test of peptide substitution degree(SD)on resin.Under different conditions,such as variation of C-termina...The efficiency of TFMSA as a cleaving reagent for peptidyl resin(I-VIII)was evaluated by quantitative ninhydrin test of peptide substitution degree(SD)on resin.Under different conditions,such as variation of C-terminal residue,resin linkage,the temperature and reaction time etc.,TFMSA can be used very conveniently instead of HF in many cases.展开更多
An efficient method for the activation of C-terminal 4-mecaptoproline-or penicillamine-containing peptide hydrazides in ligation re-actions is reported herein.The corresp on ding peptide hydrazides can be readily prep...An efficient method for the activation of C-terminal 4-mecaptoproline-or penicillamine-containing peptide hydrazides in ligation re-actions is reported herein.The corresp on ding peptide hydrazides can be readily prepared using solid-phase peptide synthesis,and subsequently activated by acetylacet one(acac)without exoge nous thiol additives.Strained peptidyl thiolactones could be the possible reactive in termediates that drastically accelerate the reacti on rates at the sterically demandi ng proline and valine sites.This developed protocol allows for sequential peptide ligations in a one-pot manner,and expedites the assembly of mucin 1(MUC-1)variable number tandem repeat(VNTR)trimers in various glycosylated forms.展开更多
Non-ribosomal peptide synthetases(NRPSs)are attractive targets for biosynthetic pathway engineering due to their modular architecture and the therapeutic relevance of their products.With catalysis mediated by specific...Non-ribosomal peptide synthetases(NRPSs)are attractive targets for biosynthetic pathway engineering due to their modular architecture and the therapeutic relevance of their products.With catalysis mediated by specific protein-protein interactions formed between the peptidyl carrier protein(PCP)and its partner enzymes,NRPS enzymology and control remains fertile ground for discovery.This review focuses on the recent efforts within structural biology by compiling high-resolution structural data that shed light into the various protein-protein interfaces formed between the PCP and its partner enzymes,including the phosphopantetheinyl transferase(PPTase),adenylation(A)domain,condensation(C)domain,thioesterase(TE)domain and other tailoring enzymes within the synthetase.Integrating our understanding of how the PCP recognizes partner proteins with the potential to use directed evolution and combinatorial biosynthetic methods will enhance future efforts in discovery and production of new bioactive compounds.展开更多
Objective To explore the probable function of peptidyl arginine deiminase 4 (PAD4) in rheumatoid arthritis (RA) .Methods Real-time quantitative polymerase chain reaction (PCR) was used to determine the expression of P...Objective To explore the probable function of peptidyl arginine deiminase 4 (PAD4) in rheumatoid arthritis (RA) .Methods Real-time quantitative polymerase chain reaction (PCR) was used to determine the expression of PAD4 mRNA in peripheral blood mononucleated cells (PBMCs) from 60 RA patients and 40 healthy individuals.Asymmetric di-methylation of histone H3R17,symmetric di-methylation and mono-methylation of H4R3were semi-quantified by Western blotting in 12 patients with osteoarthritis (OA) ,26 patients with RA and展开更多
Objective: Peptidyl alkaloids, a series of important natural products can be assembled by fungal nonribosomal peptide synthetases(NRPSs). However, many of the NRPSs associated gene clusters are silent under laboratory...Objective: Peptidyl alkaloids, a series of important natural products can be assembled by fungal nonribosomal peptide synthetases(NRPSs). However, many of the NRPSs associated gene clusters are silent under laboratory conditions, and the traditional chemical separation yields are low. In this study, we aim to discovery and efficiently prepare fungal peptidyl alkaloids assembled by fungal NRPSs.Methods: Bioinformatics analysis of gene cluster containing NRPSs from the genome of Penicillium thymicola, and heterologous expression of the putative gene cluster in Aspergillus nidulans were performed.Isolation, structural identification, and biological evaluation of the product from heterologous expression were carried out.Results: The putative tri-modular NRPS Anc A was heterologous-expressed in A. nidulans to give anacine(1) with high yield, which showed moderate and selective cytotoxic activity against A549 cell line.Conclusion: Heterologous expression in A. nidulans is an efficient strategy for mining fungal peptidyl alkaloids.展开更多
Histone citrullination,an important post-translational modification mediated by peptidyl arginine deiminases,is essential for many physiological processes and epigenetic regulation.However,the causal relationship betw...Histone citrullination,an important post-translational modification mediated by peptidyl arginine deiminases,is essential for many physiological processes and epigenetic regulation.However,the causal relationship between histone citrullination and specific gene regulation remains unresolved.In this study,we develop a programmable epigenetic editor by fusing the peptidyl arginine deiminase(PAD)PPAD from Porphyromonas gingivalis with d Cas9.With the assistance of g RNA,PPAD-d Cas9 can recruit PPADs to specific genomic loci,enabling direct manipulation of the epigenetic landscape and regulation of gene expression.Our citrullination editor allows for the site-specific manipulation of histone H3R2,8,17 and H3R26 at target human gene loci,resulting in the activation or suppression of different genes in a locus-specific manner.Moreover,the epigenetic effects of the citrullination editor are specific and sustained.This epigenetic editor offers an accurate and efficient tool for exploring gene regulation of histone citrullination.展开更多
文摘We have developed an expedient approach,＂HOPE＂（hybrid orthogonal protocol with ease） strategy for the synthesis of peptidyl N-alkylamides.This new strategy was characterized by following points：incorporating Boc and Fmoc protocols together on Merrifield resin,removal of SPG（side-chain protecting groups） without the damage of linker structure on the resin,and the ammonolysis of linker as the last step could achieve the introducing N-alkylamide structure into C-terminal and releasing product from resin-support simultaneously.In present work,eight peptidylamides with different alkylsubstitution at C-terminal were conveniently synthesized by HOPE strategy.
文摘The efficiency of TFMSA as a cleaving reagent for peptidyl resin(I-VIII)was evaluated by quantitative ninhydrin test of peptide substitution degree(SD)on resin.Under different conditions,such as variation of C-terminal residue,resin linkage,the temperature and reaction time etc.,TFMSA can be used very conveniently instead of HF in many cases.
基金The authors are grateful for financial support from the Beijing Natural Science Foundation(No.JQ18024)the National Natural Science Foundation of China(Nos.21822701,91953111,21672012)+1 种基金the Beijing Outstanding Young Scientist Program(No.BJJWZYJH01201910001001)State Key Laboratory of Natural and Biomimetic Drugs.
文摘An efficient method for the activation of C-terminal 4-mecaptoproline-or penicillamine-containing peptide hydrazides in ligation re-actions is reported herein.The corresp on ding peptide hydrazides can be readily prepared using solid-phase peptide synthesis,and subsequently activated by acetylacet one(acac)without exoge nous thiol additives.Strained peptidyl thiolactones could be the possible reactive in termediates that drastically accelerate the reacti on rates at the sterically demandi ng proline and valine sites.This developed protocol allows for sequential peptide ligations in a one-pot manner,and expedites the assembly of mucin 1(MUC-1)variable number tandem repeat(VNTR)trimers in various glycosylated forms.
基金J.C.C.was supported by the National Institute of General Medical Science(NIGMS)of the National Institutes of Health(NIH)under award number 1F31GM13761601A1J.O.S.was supported by the ACS Bridge Program and The Genentech FoundationThis work was supported by the NIGMS of the NIH under award number R01GM095970.
文摘Non-ribosomal peptide synthetases(NRPSs)are attractive targets for biosynthetic pathway engineering due to their modular architecture and the therapeutic relevance of their products.With catalysis mediated by specific protein-protein interactions formed between the peptidyl carrier protein(PCP)and its partner enzymes,NRPS enzymology and control remains fertile ground for discovery.This review focuses on the recent efforts within structural biology by compiling high-resolution structural data that shed light into the various protein-protein interfaces formed between the PCP and its partner enzymes,including the phosphopantetheinyl transferase(PPTase),adenylation(A)domain,condensation(C)domain,thioesterase(TE)domain and other tailoring enzymes within the synthetase.Integrating our understanding of how the PCP recognizes partner proteins with the potential to use directed evolution and combinatorial biosynthetic methods will enhance future efforts in discovery and production of new bioactive compounds.
文摘Objective To explore the probable function of peptidyl arginine deiminase 4 (PAD4) in rheumatoid arthritis (RA) .Methods Real-time quantitative polymerase chain reaction (PCR) was used to determine the expression of PAD4 mRNA in peripheral blood mononucleated cells (PBMCs) from 60 RA patients and 40 healthy individuals.Asymmetric di-methylation of histone H3R17,symmetric di-methylation and mono-methylation of H4R3were semi-quantified by Western blotting in 12 patients with osteoarthritis (OA) ,26 patients with RA and
基金supported financially by the Drug Innovation Major Project (No. 2018ZX09711001-006)the CAMS Initiative for Innovative Medicine (No. 2017-I2M-4-004)。
文摘Objective: Peptidyl alkaloids, a series of important natural products can be assembled by fungal nonribosomal peptide synthetases(NRPSs). However, many of the NRPSs associated gene clusters are silent under laboratory conditions, and the traditional chemical separation yields are low. In this study, we aim to discovery and efficiently prepare fungal peptidyl alkaloids assembled by fungal NRPSs.Methods: Bioinformatics analysis of gene cluster containing NRPSs from the genome of Penicillium thymicola, and heterologous expression of the putative gene cluster in Aspergillus nidulans were performed.Isolation, structural identification, and biological evaluation of the product from heterologous expression were carried out.Results: The putative tri-modular NRPS Anc A was heterologous-expressed in A. nidulans to give anacine(1) with high yield, which showed moderate and selective cytotoxic activity against A549 cell line.Conclusion: Heterologous expression in A. nidulans is an efficient strategy for mining fungal peptidyl alkaloids.
基金funded by the Tianjin Synthetic Biotechnology Innovation Capacity Improvement Project(TSBICIP-CXRC-048)。
文摘Histone citrullination,an important post-translational modification mediated by peptidyl arginine deiminases,is essential for many physiological processes and epigenetic regulation.However,the causal relationship between histone citrullination and specific gene regulation remains unresolved.In this study,we develop a programmable epigenetic editor by fusing the peptidyl arginine deiminase(PAD)PPAD from Porphyromonas gingivalis with d Cas9.With the assistance of g RNA,PPAD-d Cas9 can recruit PPADs to specific genomic loci,enabling direct manipulation of the epigenetic landscape and regulation of gene expression.Our citrullination editor allows for the site-specific manipulation of histone H3R2,8,17 and H3R26 at target human gene loci,resulting in the activation or suppression of different genes in a locus-specific manner.Moreover,the epigenetic effects of the citrullination editor are specific and sustained.This epigenetic editor offers an accurate and efficient tool for exploring gene regulation of histone citrullination.
