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.

该POWRE项目的重点是盐素敏感性突变体Haloferax Volcanii的隔离和表征。属于域古细菌的极端卤素需要盐浓度的生长盐浓度，范围为-1.5 m至5.2 m NaCl，上限超过了海水盐度的十倍。在诸如死海和大盐湖之类的敌对环境中发现了卤素，那里的盐浓度很高，几乎所有其他已知生物的生长。迄今为止，尚无使用遗传技术（例如诱变）的记录报告，其特定意图是在卤素古细菌中产生盐敏感的突变体。在这项研究中，将进行基因破坏诱变，以获得不再能够在3.5 m NaCl生长的火山螺菌突变体，这是该生物体的最佳盐浓度。将分析突变体，以确定被破坏的基因的特定位置，以引起盐敏感的表型。将确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，以确定如何根据环境中的盐度调节它们。收集的数据将导致未来的研究检查极端卤素中的基因调节。这项研究将提供第一个至关重要的步骤，以了解如何在分子水平上适应体内对超盐环境的适应性。 此外，可以收集有关古细菌用来打击他们所居住的恶劣环境影响的适应性机制的任何遗传信息都是很重要的。 该项目具有探索性，并且有可能在Powre计划的目标下推动Bidle博士的职业生涯。