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多底物协同-拮抗法同时检测超广谱β-内酰胺酶和AmpC β-内酰胺酶 被引量:7
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作者 明德松 吴一波 谢尊金 《中国感染控制杂志》 CAS 2003年第4期286-288,共3页
目的 建立一种能同时检测超广谱 β 内酰胺酶 (ESBLs)和AmpCβ 内酰胺酶 (AmpCs)的简便、实用的方法。方法 应用“多底物协同 拮抗法”(MSSAT)检测 30株阴沟杆菌 (E .cl)和 4 2株不动杆菌 (Aci)的ESBLs和AmpCs。结果 MSSAT法检出各种... 目的 建立一种能同时检测超广谱 β 内酰胺酶 (ESBLs)和AmpCβ 内酰胺酶 (AmpCs)的简便、实用的方法。方法 应用“多底物协同 拮抗法”(MSSAT)检测 30株阴沟杆菌 (E .cl)和 4 2株不动杆菌 (Aci)的ESBLs和AmpCs。结果 MSSAT法检出各种ESBLs产酶株 5 3株 (E .cl2 5株 ,Aci 2 8株 ) ;各种AmpCs产酶株 5 2株 (E .cl 1 9株 ,Aci 33株 ) ,其中高诱导型 1 0株 (E .cl8株 ,Aci2株 ) ,部分去阻遏型 1 2株 (E .cl5株 ,Aci 7株 ) ,完全去阻遏型 30株 (E .cl 6株 ,Aci 2 4株 ) ;同时产ESBLs+AmpCs产酶株 37株 (E .cl 1 5株 ,Aci 2 2株 ) ,其中ESBLs +高诱导型 4株(均为E .cl) ,ESBLs+部分去阻遏型 6株 (E .cl 5株 ,Aci 1株 ) ,ESBLs+完全去阻遏型 2 7株 (E .cl 6株 ,Aci 2 1株 )。结论 MSSAT法能同时检测ESBLs+AmpCs及其不同型 ,且准确、简便、实用。在同时产ESBLs +AmpCs的细菌中 ,E .cl以产诱导型AmpCs为主 ,Aci则以产非诱导型AmpCs为主。同时产ESBLs+AmpCs的细菌大部分取自痰标本。 展开更多
关键词 多底物协同-拮抗法 检测 超广谱Β-内酰胺酶 AmpC1β-内酰胺酶 阴沟杆菌 不动杆菌
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多底物共发酵产酸特性研究 被引量:2
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作者 边道林 孙磊 +2 位作者 王爽 郭炜 王朋峰 《黑龙江农业科学》 2014年第9期28-31,共4页
为探讨多种底物共发酵是否有利于定向产酸发酵,以牛粪、水稻秸秆、糖蜜废水为底物,分析了产酸相中不同时期pH、ORP、挥发性脂肪酸及秸秆纤维素含量的变化。结果表明:在反应器初期30d时,产酸菌群活性增长期,大量挥发性脂肪酸的产生使得p... 为探讨多种底物共发酵是否有利于定向产酸发酵,以牛粪、水稻秸秆、糖蜜废水为底物,分析了产酸相中不同时期pH、ORP、挥发性脂肪酸及秸秆纤维素含量的变化。结果表明:在反应器初期30d时,产酸菌群活性增长期,大量挥发性脂肪酸的产生使得pH迅速下降。反应后期60d,pH缓慢上升,为6.2~6.5,ORP值为-250^-400mV,满足产酸菌的生长条件。共发酵具有很强的碳源氮源互相补充的能力,有利于发酵的进行。反应120d时,水稻秸秆中纤维素得到有效降解。 展开更多
关键词 多底物 共发酵 产酸
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Order Bi Bi机制的多底物酶的非稳态酶动力学研究 被引量:10
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作者 赵敏 《温州师范学院学报》 1996年第3期67-71,共5页
本文对OrderBiBi机制的多底物酶的非稳态酶动力学机制进行了研究,推导出了此种多底物酶的非稳态动力学方程,并对此动力学方程进行了讨论,分析了多底物酶的非稳态酶动力学过程.
关键词 非稳态 多底物 酶动力学 序列有序反应
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一种基于多底物混合共代谢定向产酸发酵研究 被引量:2
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作者 李春颖 李晓燕 《哈尔滨商业大学学报(自然科学版)》 CAS 2017年第5期581-587,共7页
以牛粪、水稻秸秆、糖蜜废水的三种底物混合共代谢发酵作为CSTR的产酸相,联合IC产甲烷相进行两相厌氧发酵,其中研究的重点是提高产酸相的产酸量.通过pH值、ORP值、VFAs、TOC、TN、可溶性COD质量浓度的测定以及红外光谱(FTIR)观察水稻秸... 以牛粪、水稻秸秆、糖蜜废水的三种底物混合共代谢发酵作为CSTR的产酸相,联合IC产甲烷相进行两相厌氧发酵,其中研究的重点是提高产酸相的产酸量.通过pH值、ORP值、VFAs、TOC、TN、可溶性COD质量浓度的测定以及红外光谱(FTIR)观察水稻秸秆的降解情况.通过PCR-DGGE来观察产酸相优势种群的变化,来调节最适共代谢发酵底物,以进入产甲烷相来提高产甲烷量.结果表明,厌氧CSTR反应器发酵前30 d,反应器内pH值、ORP值均呈下降趋势,此后,反应器内pH值比较稳定,在6.2~6.5之间上下浮动,ORP值在-250^-400 m V之间浮动.反应器运行30 d,TOC、TN含量大量增加,可溶COD质量浓度上升.反应60 d时,仍能满足C/N比为27∶1,此时TOC、TN、可溶COD质量浓度含量趋于稳定,进入共代谢产酸发酵的稳定期.乙酸、丙酸、丁酸、戊酸的含量均随着时间的变化先增加后下降.随着反应进行60 d,丙酸迅速下降,没有出现酸积累现象,反应器内以乙酸为主.通过FTIR观察,发现水稻秸秆得到有效的降解.本文利用PCR-DGGE技术解析产酸相,以Clostridium bifermentans、Firmicutes bacterium、Pseudomonas aeruginosa为优势菌群. 展开更多
关键词 多底物 共代谢 混合发酵 PCR-DGGE
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高效多底物检测与多元分析方法研究进展 被引量:6
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作者 叶常青 陈硕然 +4 位作者 李风煜 葛婕 勇沛怡 秦萌 宋延林 《化学学报》 SCIE CAS CSCD 北大核心 2018年第4期237-245,共9页
传统基于锁钥模型的"一对一"响应的化学检测方式,随着时代发展已经越来越不能满足人们对复杂体系的检测需求.正交检测阵列通过对不同被检测物的差异化信息进行分析,可以获得尽可能多的响应信息,从而实现对多底物的识别检测.... 传统基于锁钥模型的"一对一"响应的化学检测方式,随着时代发展已经越来越不能满足人们对复杂体系的检测需求.正交检测阵列通过对不同被检测物的差异化信息进行分析,可以获得尽可能多的响应信息,从而实现对多底物的识别检测.多底物检测的关键是要获得尽量多的差异化传感信息.由于存在对探针需求种类量多、合成制备过程复杂、探针有效性筛选效率低等缺点,传统"多对多"方式的多元分析方法,在实际应用过程中显现出巨大的局限性.受人类感官系统的启发,发展"单对多"的高效多底物检测分析手段,将会是未来能真正走向应用的重要发展方向.从化学信息挖掘、物理信号放大与集成器件设计三个方面,针对如何提高多底物复杂分析的能力,总结简述了近期高效多底物检测与多元分析方法的研究进展. 展开更多
关键词 多底物检测 高灵敏检测 光子晶体 阵列芯片 动态分析
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Conjugated microporous polymers-scaffolded enzyme cascade systems with enhanced catalytic activity
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作者 Zhenhua Wu Jiafu Shi +6 位作者 Boyu Zhang Yushuai Jiao Xiangxuan Meng Ziyi Chu Yu Chen Yiran Cheng Zhongyi Jiang 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第8期213-223,共11页
Enhancing catalytic activity of multi-enzyme in vitro through substrate channeling effect is promis-ing yet challenging.Herein,conjugated microporous polymers(CMPs)-scaffolded integrated en-zyme cascade systems(I-ECSs... Enhancing catalytic activity of multi-enzyme in vitro through substrate channeling effect is promis-ing yet challenging.Herein,conjugated microporous polymers(CMPs)-scaffolded integrated en-zyme cascade systems(I-ECSs)are constructed through co-entrapping glucose oxidase(GOx)and horseradish peroxidase(HRP),in which hydrogen peroxide(H_(2)O_(2)) is the intermediate product.The interplay of low-resistance mass transfer pathway and appropriate pore wall-H_(2)O_(2) interactions facilitates the directed transfer of H_(2)O_(2),resulting in 2.4-fold and 5.0-fold elevation in catalytic activ-ity compared to free ECSs and separated ECSs,respectively.The substrate channeling effect could be regulated by altering the mass ratio of GOx to HRP.Besides,I-ECSs demonstrate excellent stabili-ties in harsh environments and multiple recycling. 展开更多
关键词 BIOCATALYSIS IMMOBILIZATION Enzyme cascade system Substrate channeling effect Conjugated microporous polymers
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负压驱动皮升级等温核酸精确定量微流控芯片 被引量:2
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作者 吴文帅 丁雄 牟颖 《色谱》 CAS CSCD 北大核心 2017年第3期351-356,共6页
精准医疗急需更加精确、灵敏、方便快捷的核酸定量方法。设计开发了一种结合双荧光等温扩增的高密度皮升级核酸定量微流控芯片。芯片采用多层软光刻技术制成,有3个反应通道,每通道有40 000个反应小室,共120 576个皮升级反应小室,反应小... 精准医疗急需更加精确、灵敏、方便快捷的核酸定量方法。设计开发了一种结合双荧光等温扩增的高密度皮升级核酸定量微流控芯片。芯片采用多层软光刻技术制成,有3个反应通道,每通道有40 000个反应小室,共120 576个皮升级反应小室,反应小室的密度达7 000/cm^2。芯片利用负压驱动样品精确分配,热凝固油相封闭小室,无需阀门及其他仪器辅助。芯片中嵌入的氟硅烷纳米涂层能有效地阻止反应过程中水蒸气的散失。以乙肝病毒(hepatitis B virus,HBV)质粒作为模板,进行等温多底物自配引发扩增(isothermal multiple self-matchinginitiated amplification,IMSA),测试芯片定量性能。芯片检测模板的动态范围达6个数量级,可检测的最大模板量为36μL中1.13×10~6拷贝数核酸。该装置具有定量精确、灵敏、快捷、操作简单等优势,可用于精准检测。 展开更多
关键词 微流控芯片 负压驱动 等温多底物自配引发扩增 高密度 精确定量
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Macrobenthos Community Structure and Its Relations With Environmental Factors in Three Reservoirs in Tianjin 被引量:1
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作者 姜巨峰 傅志茹 +4 位作者 李文雯 张韦 孟一耕 钱红 李相普 《Agricultural Science & Technology》 CAS 2014年第6期947-953,969,共8页
[Objective] The aim was to research macrobenthos community structure and its relations with environmental factors in three reservoirs. [Method] Benthic diversity and water quality of Yuqiao Reservoir, Beidagang Reserv... [Objective] The aim was to research macrobenthos community structure and its relations with environmental factors in three reservoirs. [Method] Benthic diversity and water quality of Yuqiao Reservoir, Beidagang Reservoir and Er- wangzhuang Reservoir were investigated in May, July and September 2011, respec- tively. []Result] Of all the 14 sampling sites, 22 species of macroinvertebrates were collected, totally, which included 6 species of aquatic insects, 7 species of Mollusca, 2 species of Crustacean, 7 species of Oligochaeta. The species of macroinverte- brates during May, July and September in Yuqiao reservoir were 11, 8 and 10, respectively. The dominant species were Chironomus sinicus, and Monopylephorus limosus. The average density and biomass of the macrobenthos were 132.43 ind./m2 and 50.09 g/m2. Yuqiao reservoir was mostly at status of premediate polluted, according to the Margalef index, Shannon index and Pielou index. The species of during May, July and September in Beidagang reservoir were 5 5 and 5, respectively. The dominant species were Chironomus sinicus, Penaeus vannamei. The average density and biomass of the macrobenthos were 218 ind./m2 and 2.70 g/m2. Beidagang reservoir was mostly at status of heavy polluted, accord- ing to the Margalef index, Shannon-wiener index, Pielou index. The species of during May, July and September in Erwangzhuang reservoir were 3, 5 and 5, respectively. The dominant species were Monopylephorus limosus, Chi- ronomus sinicus. The average density and biomass of the macrobenthos were 104 ind/m2 and 0.20 g/m2. Erwangzhuang reservoir was mostly at status of intermediate polluted, according to the Margalef index, Shannon index, Pielou index. The density of zoobenthos in Yuqiao Reservoir was positively significantly correlated with TP (P〉 0.05), negatively correlated with NH4+-N (P〉0.05), positively correlated with COD (P〈 0.01), not significantly correlated with other environment factors (P〉0.05). There was no significant correlation between biomass of zoobenthos and environment factors. The density of zoobenthos in Beidagang Reservoir with NH4+-N was positively signif- icantly correlated (P〈0.05), not significantly correlated with other aquatic environment factors (P〉0.05). There was no significant correlation between biomass of zoobenthos and environment factors. The density of zoobenthos in Erwangzhuang Reser- voir with NO3-N was positively significantly correlated (P〈0.05), not significant cor- related with other aquatic environment factors (F〉0.05). The biomass of zoobenthos in Erwangzhuang Reservoir with NH4+-N was positively significantly correlated (P〈 0.05), not significant correlated with other aquatic environment factors (P〉0.05). [Conclusion] It is indicated that this three reservoirs were all eutrophied and polluted, and the eurephication extent change of water in three reservoirs is as follows: Beidagang reservoir〉Erwangzhuang reservoir〉Yuqiao reservoir. 展开更多
关键词 MACROBENTHOS Community structure Diversity index Water quality as-sessment Large reservoirs TIANJIN
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Community characteristics of macrobenthos community in Changli Gold Coast National Nature Reserve of Hebei in China 被引量:2
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作者 KOU Cun-hui ZHANG Qing-tian +4 位作者 YU Hang LI De-liang ZHAO Xing-gui ZHANG Peng-ru-yan LIU Xian-bin 《Marine Science Bulletin》 CAS 2017年第2期38-50,共13页
Macrobenthic communities in the surrounding waters of Changli were investigated during spring and summer in2016.Differences in species quantity,abundance and biomass,the dominant species and species diversity index of... Macrobenthic communities in the surrounding waters of Changli were investigated during spring and summer in2016.Differences in species quantity,abundance and biomass,the dominant species and species diversity index of macrobenthos were analyzed.The results showed that58macrobenthos species were identified in spring,and92macrobenthos species were identified in summer.The composition of dominant species seasonally varied;however,most of them were species belonging to Polychaeta.The abundance of macrobenthos in summer was slightly higher than that in spring,while the biomass in summer was significantly smaller than that in spring.Bray-Curtis cluster analysis and multi-dimentional scaling(MDS)analysis indicated that macrobenthic communities were divided into three communities in spring,and two in summer.The abundance-biomass comparison(ABC)curve method was used to monitor the disturbance of environmental pollution for macrobenthic community.The results showed that the macrobenthos in this area received serious disturbance from environmental pollution. 展开更多
关键词 Changli MACROBENTHOS DIVERSITY cluster analysis ABC curve method
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A new species of Eunice (Polychaeta: Eunicidae) from Hainan Island, South China Sea 被引量:1
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作者 吴旭文 孙瑞平 刘瑞玉 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2013年第1期134-139,共6页
Ataxonomic survey of benthic marine animals from coastal regions of Hainan Island, South China Sea, revealed specimens of a new species of Eunice (Polychaeta: Eunicida: Eunicidae), Eunice uschakovi n. sp., collected f... Ataxonomic survey of benthic marine animals from coastal regions of Hainan Island, South China Sea, revealed specimens of a new species of Eunice (Polychaeta: Eunicida: Eunicidae), Eunice uschakovi n. sp., collected from the intertidal zone. The species belongs to the group of Eunice that has yellow tridentate subacicular hooks and branchiae scattered over an extensive region of the body. It resembles E. miurai and E. havaica in having both bidentate and tridentate falcigers, but can be readily distinguished by branchial features. Comparisons between E. uschakovi and the two related species are presented. 展开更多
关键词 ANNELIDA Eunicida TAXONOMY coastal regions intertidal zone
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Impact of Dredging on Sediment of Krishnapatnam Port, East Coast of India: Implications for Marine Biodiversity
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作者 N. Jayaju B.C. Sundara Raja Reddy K.R. Reddy 《Journal of Environmental Science and Engineering》 2010年第8期66-75,共10页
This paper synthesizes the extent and nature of scientific information about how dredging activities potentially affect habitats and key ecological functions supporting recruitment and sustainability of estuarine and ... This paper synthesizes the extent and nature of scientific information about how dredging activities potentially affect habitats and key ecological functions supporting recruitment and sustainability of estuarine and marine environment. Fourteen samples were collected after dredging (2008) from fixed sampling stations. The impact on community was estimated at species level (Foraminifera, Protozoan, using statistical analysis). The maximum negative effect on benthic foraminifera was reduction by 60%, for species richness and by 50% for diversity. This data were compared with the data obtained before dredging (2006) in a time services spanning 2 years. Its revealed that reestablishment of directly with in less than 3 months of the end of dredging, although affected foraminifera and of physico-chemical substrate characteristic 2 years later there was a considerable improvement of whole faunal community. Statistical treatment was given to the data sets to know the relation among parameters. Before, this type of activity is undertaken, each case should be studied regarding viability, the environmental medium where it will take place, the best time of year, and the type of dredging to be used. Small-patch dredging operations are proposed when ever possible, since they allow a quick readjustment of the initial sediment structure and benthic foraminifera. These findings will help to underpin improved planning of management strategies for dredging operations in India and other countries. 展开更多
关键词 Foraminifera. sediment DREDGING ecological impact krishnapatnam port east coast of India.
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Effects of a Brine Discharge over Bottom Polychaeta Community Structure in Chabahar Bay
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作者 Seyyed Mohammad Bagher Nabavi Mohadese Miri +2 位作者 Babak Doustshenas Ali Reza Safahieh Mehran Iran 《Journal of Life Sciences》 2013年第3期302-307,共6页
The brine discharge from desalination plants affects the benthic communities. Polychaetes are indicators to assess marine pollution. The aim of this study was to examine the effects of brine discharge over softbottom ... The brine discharge from desalination plants affects the benthic communities. Polychaetes are indicators to assess marine pollution. The aim of this study was to examine the effects of brine discharge over softbottom polychaete community in Chabahar Bay. Forty-two sediment samples were collected from seven stations in pre summer monsoon (April 2011) and post winter monsoon (October 2011) using Van Veen grab sampler. Changes in the polychaeta data assemblages were analyzed using univariate and multivariate techniques. Thirty-one polychaete species were identified with the highest abundance in station 6 in pre monsoon period and the lowest abundance in station 1 in pre monsoon. The results showed that the abundance, richness and diversity indices were decreased in the stations near the discharges area comparing to control stations far from the brine discharges zone. CCA (Canonical correspondence analysis) showed that salinity and temperature have influenced the community structure of polychaeta. 展开更多
关键词 Brine discharge POLYCHAETA Chabahar Bay.
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多药耐药铜绿假单胞菌产金属β-内酰胺酶的检测 被引量:6
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作者 李超 黄亮 +3 位作者 吴庆 陈栎江 刘庆中 周铁丽 《中华医院感染学杂志》 CAS CSCD 北大核心 2009年第23期3164-3167,共4页
目的分析多药耐药铜绿假单胞菌临床分离株中金属β-内酰胺酶的产生情况,并对其检测方法进行评价。方法按Aloush等的推荐标准,用K-B法对临床分离的铜绿假单胞菌进行多药耐药株的筛选,双重底物双重酶抑制剂的纸片协同法对多药耐药的铜绿... 目的分析多药耐药铜绿假单胞菌临床分离株中金属β-内酰胺酶的产生情况,并对其检测方法进行评价。方法按Aloush等的推荐标准,用K-B法对临床分离的铜绿假单胞菌进行多药耐药株的筛选,双重底物双重酶抑制剂的纸片协同法对多药耐药的铜绿假单胞菌进行产金属β-内酰胺酶表型检测,用PCR方法进行金属β-内酰胺酶IMP、VIM基因型的检测。结果1081株铜绿假单胞菌临床分离株中共筛选出192株多药耐药株;药敏结果显示,多药耐药株对环丙沙星和哌拉西林的耐药率最高,为92.5%,其次为氨曲南和复方新诺明,为91.5%,对多黏菌素全部表现为敏感;该192株多药耐药株中共检出67株金属β-内酰胺酶表型阳性,其中65株扩增出IMP或VIM基因。结论多药耐药铜绿假单胞菌的耐药机制呈复杂化、多样化表现,临床实验室应加强对此类菌株产金属β-内酰胺酶的检测。 展开更多
关键词 铜绿假单胞菌 多药耐药 金属Β-内酰胺酶 多底物多抑制剂协同试验
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Synthesis of two substrate mimics of thioesterase in the biosynthesis of cyclic depsipeptide WS9326A 被引量:1
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作者 Zhongyi Zhang Hanxuan Wang +7 位作者 Guiyang Wang Xueyang Ma Tan Liu Tongtong Geng Xiaoxu Sun Donghui Yang Suwei Dong Ming Ma 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2019年第9期605-614,共10页
WS9326 A is a tachykinin receptor antagonist and quorum sensing inhibitor discovered from several Streptomyces strains.The structure of WS9326 A features a(Z)-pentenylcinnamoyl moiety attached on a cyclic depsipeptide... WS9326 A is a tachykinin receptor antagonist and quorum sensing inhibitor discovered from several Streptomyces strains.The structure of WS9326 A features a(Z)-pentenylcinnamoyl moiety attached on a cyclic depsipeptide skeleton,which is biosynthesized by nonribosomal peptide synthetases(NRPS).The regioselective cyclization in the last step of NRPS catalysis,which is proposed to be catalyzed by a thioesterase(TE)domain in the last module,has not been experimentally characterized.We here report the synthesis of two substrate mimics(1 and 2)of the TE(WS9326 A-TE)in WS9326 A biosynthesis,by using Fmoc-based solid-phase peptide synthesis(SPPS)method.Compounds 1 and 2 are new compounds whose structures have been elucidated based on NMR and HRESIMS analyses.The N-terminal cinnamoyl moiety and C-terminal methylated L-Ser moiety in 2 were incorporated under the mild SPPS conditions.Given the isolation difficulties of substrate of WS9326 A-TE from the Streptomyces producers of WS9326 A,our synthesis of 1 and 2 set the stage for the reconstitution of WS9326 A-TE’s catalytic reaction in vitro in the future. 展开更多
关键词 Solid-phase peptide synthesis THIOESTERASE WS9326A
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