POWRE: Isolation and characterization of salt-sensitive mutants in the archaeal halophile, Haloferax volcanii

POWRE：古菌嗜盐菌 Haloferax volcanii 中盐敏感突变体的分离和表征

• 批准号: 9972968
• 负责人: Kelly Bidle
• 金额: $ 7.5万
• 依托单位: University of California-San Diego Scripps Inst of Oceanography
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-08-15 至 2001-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9972968&HistoricalAwards=false
• 关键词: POWRE; Isolation; characterization; salt; sensitive

This POWRE project focuses on the isolation and characterization of salt-sensitive mutants of the halophilic Archaeon, Haloferax volcanii. The extreme halophiles belonging to the domain Archaea require salt concentrations for growth that range from -1.5 M up to 5.2 M NaCl, an upper limit in excess of ten times the salinity of seawater. Halophiles are found in such hostile environments as the Dead Sea and the Great Salt Lake, where high concentrations of salt preclude the growth of almost all other known organisms. To date, there are no documented reports that have used genetic techniques such as mutagenesis with the specific intent of creating salt-sensitive mutants in the halophilic Archaea. In this study, gene disruption mutagenesis will be performed to obtain H. volcanii mutants that are no longer capable of growing at 3.5 M NaCl, the optimal salt concentration for this organism. Mutants will be analyzed to determine the specific location of the gene(s) that was disrupted to cause the salt-sensitive phenotype. The gene(s) responsible for salt- sensitivity will be identified and characterized. Preliminary studies will be conducted on these genes to determine how they are regulated in response to salinity in the environment. The data gathered will lead to future studies examining gene regulation in the extreme halophiles. This study will provide the first crucial steps towards understanding how the halophiles are able to adapt in vivo to hypersaline environments on the molecular level. Furthermore, any genetic information that can be gathered about the adaptational mechanisms used by the Archaea to combat the effects of the harsh environments they inhabit is of importance. This project is of an exploratory nature and has the potential to advance Dr. Bidle's career under the objectives of the POWRE program.

这个POWRE项目的重点是盐敏感突变体的嗜盐菌，Haloferax volcanii的分离和表征。极端嗜盐生物属于盐域，需要的盐浓度范围从-1.5 M到5.2 M NaCl，上限超过海水盐度的十倍。嗜盐菌在死海和大盐湖等恶劣环境中被发现，那里的高浓度盐阻止了几乎所有其他已知生物的生长。到目前为止，还没有文献报道，已使用遗传技术，如诱变的具体意图，创造盐敏感突变体的嗜盐菌。本研究采用基因中断诱变方法获得H. volcanii突变体不再能够在3.5 M NaCl（该生物体的最佳盐浓度）下生长。将分析突变体以确定被破坏以引起盐敏感表型的基因的具体位置。将鉴定和表征负责盐敏感性的基因。将对这些基因进行初步研究，以确定它们如何响应环境中的盐度而受到调节。收集的数据将导致未来的研究检查极端嗜盐生物的基因调控。这项研究将提供第一个关键步骤，了解如何嗜盐菌能够在体内适应高盐环境的分子水平。 此外，任何能够收集到的关于海蛞蝓用来对抗其所居住的恶劣环境影响的适应机制的遗传信息都是重要的。 这个项目是一个探索性的性质，并有可能推进博士Bidle的职业生涯下的POWRE计划的目标。