通过扩大非甲羟戊酸途径以实现S-柠檬烯在E.coli中的生物合成

单萜烯系香叶基焦磷酸(GPP)环化后的产物.其在食品化工医药能源等领域具有广泛的应用.目前,单萜烯主要从植物精油中纯化获得,因而产量受到限制.代谢工程是近来的新兴生物工程技术.通过改造代谢通路,可以实现在微生物中生产各类重要的产物.要实现单萜烯的微生物生产,除了要引入相应的萜烯合成酶外,还需要提高其上游产物,即异戊二烯焦磷酸(IPP)和GPP的供给.在本项工作中,我们首次通过放大E.coli的非甲羟戊酸途径,增加了IPP前体的合成,再结合引入GPP合酶及S-柠檬烯合成酶,实现了在细菌内生物合成S-柠檬烯.本研究为未来通过微生物发酵方法生产各类单萜烯产物提供了基础.     

松科植物萜类合成酶及其基因家族研究进展

萜类化合物是松科(Pinaceae)植物中重要的代谢物,它们与松科植物生长发育、信息传递、气候适应和化学防御等关系密切,在植物生理和生态等方面具有重要功能.松科植物萜类化合物还广泛应用在制药、生物燃料以及合成化学等工业领域,具有重要的经济价值.松科植物通过甲羟戊酸途径和甲基赤藓糖磷酸途径合成所有萜类物质合成所必需的5碳...     

喜树碱生物合成研究进展

喜树碱是从木本植物喜树(Camptotheca acuminata)中分离获得的一种具有抗癌活性的萜类吲哚生物碱.喜树碱年产量低,价格昂贵,提高喜树碱产量是当前临床亟需解决的问题.概述和比较了当下提高喜树碱产量的一些主流技术和方法,并对喜树碱生物合成基础研究和提高产量策略进行了讨论.     

The relationship of differential expression of genes in GA biosynthesis and response pathways with heterosis of plant height in a wheat diallel cross

Heterosis in internode elongation and plant height is commonly observed in hybrid plants, but the molecular basis for the increased internode elongation in hybrids is unknown. In this study, midparent heterosis in plant height was determined in a wheat diallel cross involving 16 hybrids and 8 parents, and real-time PCR was used to analyze alterations in gene expression between hybrids and parents. Significant heterosis of plant height and the first internode in length were observed for all 16 hybrids, but the magnitude of heterosis was variable for different cross combinations. Analysis revealed that the heterosis of the first internode was significantly correlated to that of plant height （r = 0.56, P 〈 0.05）, suggesting that the increased elongation of the first internode is the major contributor to the heterosis in plant height. Real-time PCR analysis exhibited that significant difference in heterosis of gene ex- pression was observed among all cross combinations. Moreover, heterosis of the first internode in length was correlated significantly and positively with expression heterosis of KS, GA3ox2-1, GA20ox2, GA20ox1D, GA-MYB and GID1-1, but significantly and negatively with expression heterosis of GAI and GA2ox-1, which is consistent with our recently proposed model of GAs and heterosis in wheat plant height, suggesting the alteration of GA biosynthesis and response pathways might be responsible for the observed heterosis in plant height.     

Lignin biosynthesis and its molecular regulation

Lignin biosynthesis has become increasingly highlighted because it plays an important role in the growth and development of plant, in the systematic evolution of plant and in the human life. Due to the progress in the field of lignin studies in recent years, the lignin biosynthesis pathway has been 修订日期:. Here we discuss some genetic engineering approaches on lignin biosynthesis, and conceive strategy to regulate lignin biosynthesis in order to use lignin resource more efficiently in agricultural and industrial productions.     

植物防御素研究进展

植物防御素是植物自身合成的能够抵抗环境中微生物侵害的一类小分子肽.本文对植物防御素的结构特征、类型、生物学作用、抗菌机理与模型进行了综述,并简述了其研究意义和应用前景.     

植物基因分离的方法

总结了目前植物基因分离的方法．概括出四大类植物基因分离的方法，即序列克隆法，功能克隆法。作图克隆法。表型差异克隆法，并对其特点和适用范围进行了评述。     

Nitric oxide: A potential key point of the signaling network leading to plant secondary metabolite biosynthesis

The endogenous signaling network of plants plays important roles in mediating the exogenous factor-induced biosynthesis of secondary metabolites. Nitric oxide (NO) has emerged as a key signaling molecule in plants recently. Numerous studies demonstrated that the main signaling molecules such as salicylic acid (SA), jasmonic acid (JA), reactive oxygen species (ROS), and NO were not only involved in regulating plant secondary metabolite biosynthesis but also interacted to form a complex signaling network by mutual inhibition and/or synergy. The recent progress in the signal network of plant secondary metabolite biosynthesis has been discussed in this paper. Furthermore, we propose a hypothetical model to show that NO might act as a potential molecular switch in the signaling network leading to plant secondary metabolite biosynthesis.     

Nitric oxide:A potential key point of the signaling network leading to plant secondary metabolite biosynthesis

The endogenous signaling network of plants plays important roles in mediating the exogenous factor-induced biosynthesis of secondary metabolites. Nitric oxide (NO) has emerged as a key signaling molecule in plants recently. Numerous studies demonstrated that the main signaling molecules such as salicylic acid (SA), jasmonic acid (JA), reactive oxygen species (ROS), and NO were not only involved in regulating plant secondary metabolite biosynthesis but also interacted to form a complex signaling network by mutual inhibition and/or synergy. The recent progress in the signal network of plant secondary metabolite biosynthesis has been discussed in this paper. Furthermore, we propose a hypothetical model to show that NO might act as a potential molecular switch in the signaling network leading to plant secondary metabolite biosynthesis.     

植物组织褐变的研究进展

外植体的褐变是植物组织培养过程中的主要障碍，从酶促褐变的底物和多酚氧化酶出发，阐述了国内外有关外植体褐变的研究现状、褐变发生的机理及防止措施等问题，并对目前所提出的各种机理假说作了评价。     

甜菜碱及其生物合成相关酶的基因工程研究进展

本介绍了甜菜碱在植物抗逆生理中的非渗透调节功能及其生物合成酶的基因工程研究的最新进展,并提出了开展此研究的一些设想。