白藜芦醇合成酶基因在基因工程中的应用及功能研究进展

白藜芦醇合成酶(Resveratrol synthase,RS)是白藜芦醇(Resveratrol,Res)合成途径中的关键酶。以往研究报道,RS基因已在多种植物和微生物中进行了转化和表达,并在植物的代谢及调控等方面发挥生物学作用。文中主要围绕RS基因对植物的转化,及异源表达后植物体内代谢产物的变化,转RS基因对植物抗病原菌活性、抗自由基活性和生长发育的影响,以及利用RS基因在微生物中生产Res的相关进展进行了综述。并对RS基因在生物工程方面的应用前景进行展望。     

植物天然产物微生物重组合成研究进展

植物天然产物是小分子药物、营养品、化妆品、香精香料等的主要来源之一,在国民经济中发挥重要的作用。目前植物天然产物主要依赖于植物提取,这种生产方式占用耕地、生长周期长,而且植物活性成分往往含量低、生产成本高。通过解析植物天然产物生物合成途径,在微生物细胞中重构,创建细胞工厂,实现利用可再生原料发酵合成,为植物天然产物的供给提供了新的路线。本文重点介绍了中国科学院天津工业生物技术研究所在萜类、黄酮类、苯丙素类等重要类型植物天然产物微生物重组合成方面的研究进展,简要探讨了当前研究面临的挑战及未来前景。     

代谢工程改造酿酒酵母合成植物萜类D-柠檬烯的策略

植物萜类化合物是以异戊二烯为结构单位的一大类植物天然的次生代谢产物。D-柠檬烯属于单萜类化合物,由于它具有抑菌、增香、抗癌、止咳、平喘等多种功能,已被广泛应用于食品、香料、医疗等行业。目前D-柠檬烯的工业生产主要是从植物的果皮或者果肉中提取的,但提取方法存在着分离纯化复杂、产率低、能耗大等缺点。而本世纪初合成生物学技术的兴起,为微生物异源合成天然活性化合物带来了全新的理念与工具,打破了物种间的界限,使微生物异源合成D-柠檬烯成为现实。构建定向、高效的异源合成D-柠檬烯的微生物细胞工厂,实现微生物发酵法替换传统的植物提取法,具有重要的经济与社会效益。本文主要回顾了近几年利用代谢工程改造酿酒酵母异源合成萜类化合物取得的成就,阐述了以酿酒酵母作为底盘微生物,利用代谢工程和合成生物学的手段构建高产D-柠檬烯的合成策略。     

微生物异源合成植物异喹啉生物碱的新进展

植物异喹啉生物碱(plant isoquinoline alkaloids,PIAs)包括吗啡、可待因、加兰他敏及小糵碱等药用活性产物和其他天然活性产物。从植物中提取异喹啉生物碱,受制于低含量、种植季节及提取方法。人们开始研究利用微生物异源合成和改造天然异喹啉生物碱,从而获得低成本的药用活性物质。异喹啉生物碱合成途径长,反应复杂,为实现微生物异源合成带来了诸多挑战。随着合成途径和酶的解析和鉴定,合成生物学技术为在微生物中合成异喹啉生物碱提供了可能。综述了PIAs合成途径解析的最新进展,以及微生物异源合成PIAs的代谢工程策略,讨论了目前存在的问题和未来的发展趋势。     

白藜芦醇代谢物的研究进展

白藜芦醇是一些植物在受到生物和非生物胁迫时产生的一种植物抗毒素.它在植物体内会迅速被代谢而生产紫檀芪、云杉新苷、viniferins等代谢物.这些代谢物与白藜芦醇一样具有抗菌、消炎、抗血小板凝集、防止细胞癌变等一系列的生物活性,且有些代谢物的选择性、稳定性远远大于白藜芦醇.本文对白藜芦醇代谢物中几种主要代谢物的合成途径、生物活性、代谢调控、检测方法等进行了综述.     

异源表达CiRS基因通过生成白藜芦醇增强拟南芥的抗氧化能力

白藜芦醇是一种具有多种医疗保健作用的植物芪类次生代谢产物,在农业、医药、食品和化妆品等领域受到广泛的关注。白藜芦醇合酶是白藜芦醇生物合成中唯一必需的关键酶,决定植物体内白藜芦醇的合成。将中间锦鸡儿中克隆到的CiRS基因(Gen Bank登录号MF678590)转入野生型拟南芥,实验结果显示:野生型的总黄酮含量明显高于转基因株系。HPLC测得转基因拟南芥中有白藜芦醇的生成,并且含量最高达335μg/g FW。紫外照射处理后转基因植物中丙二醛的积累量明显少于野生型。转基因植物提取物DPPH自由基清除能力均高于野生型。这些结果表明,中间锦鸡儿CiRS基因异源表达后利用与黄酮类物质的共同底物合成了白藜芦醇,使得转基因植物的抗氧化性增强。     

白藜芦醇在糖尿病治疗中的作用

白藜芦醇(resveratrol)是一种从植物中提取的多酚类化合物,它广泛存在于葡萄等植物中。白藜芦醇具有广泛的生物学活性,抗氧化、抗癌和调节代谢等作用。白藜芦醇在治疗糖尿病(diabetes mellitus, DM)中可有效改善胰岛β细胞功能及刺激胰岛素的分泌。白藜芦醇的作用机制较为复杂,现就白藜芦醇在DM治疗中的作用及机制作一概述。     

白藜芦醇植物资源及其生产

白藜芦醇广泛存在于多种植物中,具有抗肿瘤、抗病毒等重要生物活性。综述了白藜芦醇在植物中的分布及其生产,特别是生物技术在生产中的应用,为白藜芦醇在药品和功能食物方面的进一步开发提供参考。     

白藜芦醇的研究进展

白藜芦醇是一种含有芪类结构的非黄酮类多酚化合物.它不仅是植物遭受胁迫时产生的一种能提高植物抵抗病原性攻击和环境恶化的植物抗毒素,还具有抗癌,抗氧化、调节血脂,影响寿命等多方面有益于人类健康的重要功能.以下对白藜芦醇的理化特性、合成、提取、纯化与检测方法进行了全面总结,并在其作用的分子机制基础上,对其生物学活性、基因工程研究及产业化情况进行了重点介绍.发现在传统育种的基础上,借助于现代生物技术手段,将白藜芦醇的天然活性保健作用应用于保健食品的开发、作物经济附加值的提高具有广阔的前景.它的开发和利用,必将为食品及制药工业新产品的开发提供新的挑战与机遇.     

大肠杆菌中从头合成白藜芦醇途径的设计及优化

白藜芦醇是一种极具药用价值的植物源芪类化合物。为了在E. coli实现白藜芦醇的从头合成,构建了由酪氨酸解氨酶（TAL）,香豆酸-CoA合成酶（4CL）和白藜芦醇合成酶（STS）组成的非天然合成途径。经3天发酵后,白藜芦醇产量仅为2.67 mg/L,而其中间体香豆酸的积累达到了95.64 mg/L。为了进一步改善异源途径的效率,对4CL和STS模块采取融合表达、高拷贝表达及启动子工程改造的策略,最终使白藜芦醇产量提高到了9.6倍,达到了25.76 mg/L,同时香豆酸的积累减少到了20.38 mg/L。这些研究结果为更高效白藜芦醇从头合成工程菌的构建及最终实现白藜芦醇的微生物大规模生产奠定了基础。     

DNA damage is a late event in resveratrol-mediated inhibition of Escherichia coli

Resveratrol is an important phytoalexin notable for a wide variety of beneficial activities. Resveratrol has been reported to be active against various pathogenic bacteria. However, it is not clear at the molecular level how this important activity is manifested. Resveratrol has been reported to bind to cupric ions and reduce it. In the process, it generates copper-peroxide complex and reactive oxygen species (ROS). Due to this ability, resveratrol has been shown to cleave plasmid DNA in several studies. To this end, we envisaged DNA damage to play a role in resveratrol mediated inhibition in Escherichia coli. We employed DNA damage repair deficient mutants from keio collection to demonstrate the hypersensitive phenotype upon resveratrol treatment. Analysis of integrity and PCR efficiency of plasmid DNA from resveratrol-treated cells revealed significant DNA damage after 6?h or more compared to DNA from vehicle-treated cells. RAPD-PCR was performed to demonstrate the damage in genomic DNA from resveratrol-treated cells. In addition, in situ DNA damage was observed under fluorescence microscopy after resveratrol treatment. Further resveratrol treatment resulted in cell cycle arrest of significant fraction of population revealed by flow cytometry. However, a robust induction was not observed in phage induction assay and induction of DNA damage response genes quantified by promoter fused fluorescent tracker protein. These observations along with our previous observation that resveratrol induces membrane damage in E. coli at early time point reveal, DNA damage is a late event, occurring after a few hours of treatment.     

白藜芦醇合酶的研究进展

白藜芦醇是一种重要的植物抗毒素,具有多种医疗保健作用,因此其应用前景 非常广泛,已引起多方关注。白藜芦醇合酶是白藜芦醇生物合成途径中的关键酶之一,它催化1分子4-香豆酰辅酶A和3分子丙二酰辅酶A反应合成白藜芦醇,它是白藜芦醇生物合成中惟一必需的酶,关于它的研究已广泛开展起来。本文综述了白藜芦醇的药理活性、白藜芦醇合 酶的酶学性质、诱导途径和机制以及分子生物学方面的研究进展。     

Resveratrol Ameliorates Imiquimod-Induced Psoriasis-Like Skin Inflammation in Mice

BackgroundThe polyphenol resveratrol has anti-inflammatory effects in various cells, tissues, animals and human settings of low-grade inflammation. Psoriasis is a disease of both localized and systemic low-grade inflammation. The Sirtuin1 enzyme thought to mediate the effects of resveratrol is present in skin and resveratrol is known to down regulate NF-κB; an important contributor in the development of psoriasis. Consequently we investigated whether resveratrol has an effect on an Imiquimod induced psoriasis-like skin inflammation in mice and sought to identify candidate genes, pathways and interleukins mediating the effects.MethodsThe study consisted of three treatment groups: A control group, an Imiquimod group and an Imiquimod+resveratrol group. Psoriasis severity was assessed using elements of the Psoriasis Area Severity Index, skin thickness measurements, and histological examination. We performed an RNA microarray from lesional skin and afterwards Ingenuity pathway analysis to identify affected signalling pathways. Our microarray was compared to a previously deposited microarray to determine if gene changes were psoriasis-like, and to a human microarray to determine if findings could be relevant in a human setting.ResultsImiquimod treatment induced a psoriasis-like skin inflammation. Resveratrol significantly diminished the severity of the psoriasis-like skin inflammation. The RNA microarray revealed a psoriasis-like gene expression-profile in the Imiquimod treated group, and highlighted several resveratrol dependent changes in relevant genes, such as increased expression of genes associated with retinoic acid stimulation and reduced expression of genes involved in IL-17 dependent pathways. Quantitative PCR confirmed a resveratrol dependent decrease in mRNA levels of IL-17A and IL-19; both central in developing psoriasis.ConclusionsResveratrol ameliorates psoriasis, and changes expression of retinoic acid stimulated genes, IL-17 signalling pathways, IL-17A and IL-19 mRNA levels in a beneficial manner, which suggests resveratrol, might have a role in the treatment of psoriasis and should be explored further in a human setting.     

SIR2 calls upon the ER

Resveratrol induces longevity in C. elegans through the action of SIR2. Recently published work shows that resveratrol induces genes of the unfolded protein stress response of the endoplasmic reticulum. Paradoxically, these stress genes are repressed by SIR2, suggesting that resveratrol increases life span by inhibiting this SIR2 action.     

白藜芦醇合酶的研究进展

白藜芦醇是一种重要的植物抗毒素,具有多种医疗保健作用,因此其应用前景非常广泛,已引起多方关注。白藜芦醇合酶是白藜芦醇生物合成途径中的关键酶之一,它催化1分子4—香豆酰辅酶A和3分子丙二酰辅酶A反应合成白藜芦醇,它是白藜芦醇生物合成中惟一必需的酶,关于它的研究已广泛开展起来。本文综述了白藜芦醇的药理活性、白藜芦醇合酶的酶学性质、诱导途径和机制以及分子生物学方面的研究进展。     

Production of a major stilbene phytoalexin, resveratrol in peanut (Arachis hypogaea) and peanut products: a mini review

As a major stilbene phytoalexin, resveratrol is produced or elicited in several plant species as a part of defense systems protecting plants against diseases. Resveratrol can be present in both the trans- and cis-isomeric forms, and only the trans-form increases the life expectancy and lowers the risk of cardiovascular diseases as the most bioactive form. In addition to the usages for diet and industry, peanut plant (Arachis hypogaea) and peanuts are getting higher attention due to their containment of resveratrol in the kernels and other parts of peanut plant, such as leaves, roots, and peanut shell. Recently, natural resveratrol derived from peanuts has also become a promising nutraceutical agent, promoting human health. Resveratrol has also been detected in peanut products including peanut butters, roasted peanuts, and boiled peanuts. Although, smaller and immature peanuts contain higher levels of resveratrol than mature peanuts, resveratrol in peanuts can also be preserved by cooking or manufacturing processes. Moreover, the amount of resveratrol in peanut plants and peanuts has been found to increase by external stimuli including microbial infection, wounding, UV light irradiation, ultrasonication, yeast extract treatment and by plant stress hormones. In addition, molecular level analysis has confirmed that four resveratrol synthase (RS) genes (RS1, RS2, RS3 and RS4) which catalyze synthesis of resveratrol have been identified in peanuts, and up-regulation of the genes is positively correlated to the increased contents of resveratrol. In this review, we summarize the natural biosynthesis of resveratrol in peanuts and peanut plants, as well as the occurrence of this natural phytoalexin in various peanut products. A brief knowledge on the biosynthetic pathway of resveratrol synthesis has been described. This review also deals on highlighting the effect of various external stimuli (biotic and abiotic stresses) in order to achieve the maximum induction and/or elicitation of resveratrol in peanuts and peanut plants.