基因工程微生物生态学研究进展

基因工程微生物(genctically enginccred microorganism,GEM)生态学的研究已成为微生物分子生态学的一项主要研究内容之一．随着分子标记和分子生物学检测手段的引入,传统的微生物生态学研究被注入了新的活力,在分子水平上探讨基因工程微生物与环境及环境中土著生物之间的关系已成为可能．基因工程微生物生态学是一门内容涉及分子生物学、微生物学、生态学等诸多学科的新型交叉边缘学科．本文提出加紧进行转基因生物生态学和转基因生物的风险评价的研究工作,建立适合中国国情的检测手段和评价标准,有助于我国基因工程微生物生态学的健康发展．     

转基因植物的生态风险评价

自从１９８３年第一株转基因植物诞生以来,至今各种类型的转基因植物进入大田试验的已不计其数,近１０种转基因作物的产物已经商品化。与此同时,转基因植物向环境释放后可能带来的生态风险问题也越来越受到人们的重视。关于转基因植物的生态风险或对环境的危害,科学家提出了不同的概念和测试方法。生态毒理学的经验以及８０年代发展起来的,为作环境决策用的生态风险评价的经验可以借鉴以作转基因植物生态风险的评价。本文介绍了转基因植物对农田生态系统和自然生态系统可能带来的危害以及从基因、基因组、个体、种群以至生态系统等各级水平上危害测试的方法。对风险的判断作了详细的论述,对风险的管理也作了概略的介绍,并对生态风险评价当前发展的水平进行了讨论。     

Purdue模型表明转基因生物的生态学风险将无法预测

美国WestLafayette的普渡（Purdue）大学有两位科学家认为将转基因生物释放到野外所带来的引起自然界物种消亡的理论风险要比我们先前预计的大得多。动物学教授WillianMuir和生物学教授RichardHoward采用计算机模型和统计分析对转基因生物转入野外的假定风险进行了研究。由于新的转基因生物的范围几乎是无限的,两位教授的工作对于发展转基因生物时预测它们可能造成的危险具有建设性的意义。新的计算机模型表明生物消亡的风险要比我们以前所认为的大得多,转基因生物将导致自然群体的消亡。Muir说,“就宏观而言,此项研究告诉我们如何…     

未培养微生物的研究与微生物分子生态学的发展*

近年来现代分子技术和基因组学逐渐渗透到有关生命科学的整个领域,也为微生物生态学提供了新的研究方法和机遇。16S rRNA基因序列分析、DNA-DNA杂交、核酸指纹图谱以及宏基因组学等分子技术检查自然环境中的微生物,可以克服传统纯培养技术的不足,是一条探知未培养微生物、寻找新基因及其产物的新途径,开启了我们认识微生物多样性和获得新资源的大门。     

微生物分子生态学技术在湖泊微生物多样性研究中的应用

微生物是湖泊生物圈物质循环和能量流动的主要参与者,在湖泊的生态系统中起着重要的作用。但是,湖泊中存在着大量不可培养的细菌,利用传统的培养技术,无法对湖泊微生物的多样性进行深入而全面的研究,而不依赖培养的分子生物学技术的发展为此方面研究开辟了新的路径。微生物分子生态学作为分子生物学与微生物生态学交叉产生的学科,在研究湖泊微生物多样性方面已经得到了广泛的应用。主要综述了变性梯度凝胶电泳(PCR-DGGE)技术,末端限制性酶切片段长度多态性技术(T-RFLP),16SrDNA克隆文库技术等微生物分子生态学技术在研究湖泊微生物多样性方面的应用情况。     

微生物分子生态学发展历史及研究现状

微生物群落多样性是微生物生态学和环境学研究的重点之一。分子生物学方法应用于微生物群落结构分析使得对环境样品中占大多数的不可培养微生物的研究成为了可能。由于功能上高度保守,序列上的不同位置具有不同的变异速率,核糖体RNA（rRNA）是目前在微生物分子生态学上最为有用以及应用最广泛的分子标记,通过rRNA序列比对,可以分析不同分类水平的系统发育关系。元基因组学研究方法通过对环境样品中的各种微生物群落的总的基因组进行分析,充分展示了环境微生物代谢途径,极大地扩展了对微生物的认识。快速发展的高通量测序极大地促进了各项微生物生态学技术的发展,带来了新的突破。     

海洋微生物多样性及其分子生态学研究进展

海洋微生物多样性的深入研究将有助于微生物资源更好的开发和利用,海洋微生物多样性有很大的研究价值和研究空间。海洋中大多数微生物处于未可培养状态,在分子生态学基础上对海洋未可培养微生物进行研究是当今微生物多样性研究的主要方向。近年来相关研究进展迅速,研究方法不断更新。主要从分子生态学角度对微生物多样性研究现状进行概述并详细分析探讨了相关的研究方法,而且从分子生态学与海洋微生物多样性研究相结合的层面,对本领域的研究进行展望。旨在为海洋微生物多样性的研究及海洋资源的可持续开发与利用提供参考。     

微生物分子生态学研究方法及其存在的缺陷

微生物群落多样性是微生物生态学和环境学研究的重点之一.分子生物学方法应用于微生物群落结构分析使得对环境样品中占大多数的不可培养微生物的研究成为了可能.然而,PCR过程中的偏差(bias)会引起结果并不能如实地再现原始的群落结构,随着多个宏基因组项目的研究,发现所谓的“通用引物”并不能覆盖全部的微生物类型,即使可以添加简并碱基,也无法与通过宏基因组得到的rRNA序列完全匹配,这导致了在诸多研究中会忽略环境中的微生物群落.即使是不经过PCR扩增的元基因组和元转录组学研究方法,对于分子微生物群落也存在着一定的问题.     

FISH技术在微生物生态学中的研究及进展

分子生物学技术在微生物生态学研究中具有灵敏、精确和快速的优势,但不能提供微生物的形态学、数量性状、空间分布等信息。荧光原位杂交技术结合了分子生物学的精确性和显微镜的可视性信息,可以在自然生境中监测和鉴定不同的微生物个体,尤其是对难培养和未被培养的微生物进行检测。荧光原位杂交技术被广泛用于微生物群落结构诊断和评价,现已成为微生物分子生态学研究中的热点技术。对荧光原位杂交技术的发展和在微生物分子生态学中的应用进行了综述,探讨了该技术应用中存在的问题和发展前景。     

Rapid method for the detection of genetically engineered microorganisms by polymerase chain reaction from soil and sediments

A rapid and sensitive method for the detection of genetically engineered microorganisms in soil and sediments has been devised by in vitro amplification of the target DNAs by a polymerase chain reaction. A cloned catechol 2,3-dioxygenase gene located on the recombinant plasmid pOH101 was transferred to Pseudomonas putida MMB2442 by triparental crossing and used as a target organism. For the polymerase chain reaction from soil and sediment samples, the template DNA was released from a 100-mg soil sample. Bacterial seeded soil samples were washed with Tris-EDTA buffer (pH 8.0) and treated with a detergent lysis solution at 100°C. After addition of 1% polyvinylpolypyrrolidine solution, the samples were boiled for 5 min. Supernatant containing nucleic acid was purified with a PCR purification kit. The purified DNA was subjected to polymerase chain reaction, using two specific primers designed for the amplification of catechol 2,3-dioxygenase gene sequences. The detection limit was 10² cells per gram of soil. This method is rapid and obviates the need for lengthy DNA purification from soil samples. Received 28 February 1997/ Accepted in revised form 23 November 1997     

Patenting of hybridomas and genetically engineered microorganisms

Summary Many new technologies arrived at through basic research have practical applications. Two recent breakthroughs in microbiology, recombinant DNA techniques and hybridoma techniques, will permit designing cells for specific practical purposes resulting in new products or functions of commercial significance. The unique cell or its usefulness, or both, may satisfy the requirements of a patentable invention, i.e. an inventive act having utility and novelty. Ownership of such patents permits recovery of expenses incurred in the invention process and investment for all concerned in additional research. An integral part of the patenting process is submission of the new cell to an official repository, an outstanding example of which is The American Type Culture Collection.     

基因工程生物的生态影响及其评价

随着基因工程技术的迅速发展,基因工程产生的生物将被广泛地应用于非受控的自然环境中,这将带来诸多的环境和生态方面的问题。本文概述了基因工程生物在非受控环境下可能产生的生态影响,提出了“基因工程生态学”这一新的应用生态学分支领域,探讨了该分支学科的概念、主要研究内容和目标,以及当前应采取的研究策略,并就发展基因工程生态学的有关问题提出了建议。     

Procedures for microencapsulation of enzymes, cells and genetically engineered microorganisms

Methods to microencapsulate enzyme, cells, and genetically engineered cells have been described in this article. More specific examples of enzyme encapsulation include the microencapsulation of xanthine oxidase for Lesch-Nyhan disease; phenylalanine ammonia lyase for pheny, ketonuria and microencapsulation of multienzyme systems with cofactor recycling for multistep enzyme conversions. Methods for cell encapsulation include the details for encapsulating hepatocytes for liver failure and for gene therapy. This also includes the details of a novel two-step method for encapsulation of high concentrations of smaller cells. Another new approach is the detailed method of the encapsulation of genetically engineered Escherichia coli DH5 cells for lowering urea, ammonia, and other metabolites in kidney or, liver failure and other diseases.     

Molecular methods for environmental monitoring and containment of genetically engineered microorganisms

Plans to introduce genetically engineered microorganisms into the environment has led to concerns over safety and has raised questions about how to detect and to contain such microorganisms. Specific gene sequences, such as lacZ, have been inserted into genetically engineered microorganisms to permit their phenotypic detection. Molecular methods have been developed based upon recovery of DNA from environmental samples and gene probe hybridization to specific diagnostic gene sequences for the specific detection of genetically engineered microorganisms. DNA amplification using the polymerase chain reaction has been applied to enhance detection sensitivity so that single gene targets can be detected. Detection of messenger RNA has permitted the monitoring of gene expression in the environment. The use of reporter genes, such as the lux gene for bioluminescence, likewise has permitted the observation of gene expression. Conditional lethal constructs have been developed as models for containment of genetically engineered microorganisms. Suicide vectors, based upon the hok gene have been developed as model containment systems.     

低剂量混合污染生态毒理与风险评价研究进展

环境中的化学品往往以低剂量混合形式存在.对单一化学品高剂量暴露下的生态毒性研究成果,难以适用于环境中低剂量混合物的生态毒理效应诊断及风险评价.文中概述了低剂量化学品混合污染生态毒理及风险评价方面的研究进展,主要包括低剂量化学品混合污染诊断的分子毒理研究方法、风险评价方法,并介绍了简单和复杂混合物的风险评价方案.对低剂量混合污染生态毒理与风险评价研究的发展动向提出了见解,指出低剂量化学混合物的研究需要寻找敏感终点,引入多学科手段,积累更多的数据,建立完善、统一的评价体系.     

Ecological risk assessment of genetically modified crops based on cellular automata modeling

The assessment of ecological risk in genetically modified (GM) biological systems is critically important for decision-making and public acceptance. Cellular automata (CA) provide a potential modeling and simulation framework for representing relationships and interspecies interactions both temporally and spatially. In this paper, a simple subsystem contains only four species: crop, target pest, non-target pest and enemy insect, and a three layer arrangement of L × L stochastic cellular automata with a periodic boundary were established. The simulation of this simplified system showed abundant and sufficient complexity in population assembly and densities, suggesting a prospective application in ecological risk assessment of GM crops.     

微生物分子生态学技术及其在环境污染研究中的应用

较为系统地概述了核酸探针检测技术、利用引物的PCR技术、DNA序列分析技术和电泳分离及显示技术在国内外的研究进展,并探讨了这些技术在环境污染研究中的应用及其方向。结果表明,这些被认为是重要的微生物分子生态学技术,在探索微生物与污染环境之间的相互关系中发挥了重要作用。促进了污染环境的微生物遗传适应进化机制的研究,污染物的微生物降解有关基因的定位及微生物工程菌的构建等方面的工作,从而推进了污染环境微生物修复的分子生态学的发展。     

机场鸟撞防制中的鸟类风险评价

机场的鸟类由于其所处位置的特殊性,会对飞行安全造成一定威胁。各种鸟类因其自身特征,风险大小也各有不同。在实际调查的基础上,建立了风险评价指标体系,构建了机场鸟类风险评价的实用数学模型,给出了一种度量鸟类风险的简单、合理的科学方法,并就具体实例进行了分析研究。计算结果表明,在所有观察到的70种鸟类中,风险很大者占总数的24.29%,风险较大者占30.00%,风险一般者占30.00%,风险较小者占15.71%。其中风险很大和较大的鸟类应是机场重点防治的对象。就各鸟类的单个风险评价指标也给出了定量结果。以上风险分析结果,为鸟类风险评价和机场鸟害防治提供了定量依据。     

Genetically engineered trees for plantation forests: key considerations for environmental risk assessment

Forests are vital to the world's ecological, social, cultural and economic well‐being yet sustainable provision of goods and services from forests is increasingly challenged by pressures such as growing demand for wood and other forest products, land conversion and degradation, and climate change. Intensively managed, highly productive forestry incorporating the most advanced methods for tree breeding, including the application of genetic engineering (GE), has tremendous potential for producing more wood on less land. However, the deployment of GE trees in plantation forests is a controversial topic and concerns have been particularly expressed about potential harms to the environment. This paper, prepared by an international group of experts in silviculture, forest tree breeding, forest biotechnology and environmental risk assessment (ERA) that met in April 2012, examines how the ERA paradigm used for GE crop plants may be applied to GE trees for use in plantation forests. It emphasizes the importance of differentiating between ERA for confined field trials of GE trees, and ERA for unconfined or commercial‐scale releases. In the case of the latter, particular attention is paid to characteristics of forest trees that distinguish them from shorter‐lived plant species, the temporal and spatial scale of forests, and the biodiversity of the plantation forest as a receiving environment.