Collaborative Research: CMG--Toward Understanding the Transfer of Genetic Information in Subsurface Hydrology

合作研究：CMG——了解地下水文学中遗传信息的传递

• 批准号: 0620460
• 负责人: John Cushman
• 金额: $ 33.6万
• 依托单位: Purdue University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-09-15 至 2009-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0620460&HistoricalAwards=false
• 关键词: Collaborative; Research; CMG; Toward; Understanding

The transfer of genetic information in the environment has been an important issue among scientists and the public for several decades. Its importance first became apparent with the rapid spread of antibiotic resistance to pathogenic bacteria. Then genomic analysis revealed that gene transfer has played an important role in bacterial evolution. Recently there have been public concerns about risks associated with gene transfer from genetically engineered organisms to indigenous organisms and the possible consequences in the environment. Cell to cell transfer is one of the primary means by which genes can be propagated in natural geologic formations into alternate hosts. Although the process has been documented and exchange occurs under laboratory conditions, very little is known about the frequency of these events in the subsurface. The natural geologic environment is heterogeneous, and therefore it has been impossible to test every variable experimentally over a hierarchy of scales. By combining experiment with theory the investigators target identification of the major requirements for successful gene transfer and the rates at which it occurs under particular conditions. The transfer of genetic material among bacteria in the environment can occur both in the planktonic and attached state. This study focuses on the development and application of mathematics to describe the fundamental aspects associated with horizontal gene transfer within biofilms in the subsurface. The mathematics used to describe bacterial transport in porous media has been focused on colloid transport mechanisms for single cell or cell clump transport. These two fields are so far in nearly complete isolation from each other. Here the investigators propose experiments and modeling designed to test hypotheses regarding transfer in porous media at multiple scales, and to elucidate priority mechanisms controlling transfer among bacteria undergoing transport, attachment, and biofilm formation.

几十年来，遗传信息在环境中的转移一直是科学家和公众的一个重要问题。随着病原菌抗生素耐药性的迅速传播，它的重要性首次变得显而易见。基因组分析表明，基因转移在细菌进化中发挥了重要作用。最近，公众对基因工程生物向土著生物转移基因的风险及其可能对环境造成的后果表示关注。细胞间转移是基因在自然地质构造中繁殖到替代宿主中的主要手段之一。虽然这一过程已被记录在案，而且交换发生在实验室条件下，但人们对这些事件在地下发生的频率知之甚少。自然的地质环境是不均匀的，因此不可能在一系列尺度上对每个变量进行实验测试。通过将实验与理论相结合，研究人员的目标是确定成功的基因转移的主要要求以及在特定条件下发生的速率。环境中细菌之间遗传物质的转移可以在附着状态和附着状态下发生。本研究的重点是数学的发展和应用，以描述与地下生物膜内的水平基因转移相关的基本方面。用于描述多孔介质中细菌运输的数学方法一直集中在单细胞或细胞团运输的胶体运输机制上。到目前为止，这两个领域几乎完全相互隔离。在这里，研究人员提出了实验和建模，旨在测试假设在多孔介质中的传输在多个尺度，并阐明优先机制控制细菌之间的传输进行运输，附着和生物膜形成。