Envelope Components of Gliding Bacteria

滑动细菌的包膜成分

• 批准号: 9220647
• 负责人: Edward Leadbetter
• 金额: $ 27.7万
• 依托单位: University of Connecticut
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1993
• 资助国家: 美国
• 起止时间: 1993-03-01 至 1997-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9220647&HistoricalAwards=false
• 关键词: Envelope; Components; Gliding; Bacteria

Many bacteria are able to move over solid surfaces (often these are biological polymers such as agar, cellulose, chitin, pectin, or xylan) by a process termed gliding. This is an important aspect of these organisms' central role in the mineralization processes which so many "higher" forms of life are unable to effect, but upon which they are dependent. The mechanism by which the gliding bacteria accomplish this translocation remains a mystery; however, the sulfonolipids first isolated and described in this laboratory are the first molecules to be recognized as necessary (in the cytophagas an flexibacters) for gliding motility. A cell-surface polysaccharide also plays an accessory role. The current focus on the features of the cell envelope that are important in cell translocation will include a peptidoglycan-associated protein and other cell envelope features that change when a particular nongliding mutant regains, reversibly, the ability to glide. %%% The question of how gliding bacteria glide has been one of the most intractable problems in microbiology. There are no morphological clues to the mechanism of gliding. A number of laboratories have been working on the problem for many years, using both genetic and biochemical approaches, with minimal success. The Leadbetter laboratory made a breakthrough discovery when it was found that a particular nongliding mutant of Cytophaga johnsonae had a defect in the pathway of biosynthesis of a novel sulfonolipid, and that the nongliding phenotype could be reversed by the addition of the appropriate metabolic precursor (cysteate) to the culture medium. This project is a biochemical followup to that seminal discovery, and holds the promise of actually deciphering the nature of the bacterial molecule(s) involved in the gliding mechanism.

许多细菌能够在固体表面上移动（通常是这些 是生物聚合物，例如琼脂、纤维素、几丁质、果胶，或 木聚糖）通过称为滑动的过程。 这是一个重要的方面， 这些生物在矿化过程中的中心作用， 如此多的“更高”的生命形式无法影响，但在 他们是依赖的。 滑翔细菌的机制 完成这种易位仍然是一个谜;然而， 本实验室首次分离和描述的磺脂类是 第一个被认为是必要的分子（在 细胞吞噬菌和弯曲菌）用于滑行运动。 细胞表面 多糖也起辅助作用。 本期关注 在细胞中重要的细胞包膜特征 易位将包括肽聚糖相关蛋白， 其他单元格包络特征，当特定 nongliding突变恢复，可逆，滑翔的能力。 %%% 滑翔细菌如何滑翔的问题一直是 微生物学中棘手的问题 没有形态学上的 滑翔机制的线索 一些实验室已经 多年来一直在研究这个问题，利用基因和 生物化学方法，收效甚微。 利百特 一个实验室有了突破性的发现， 一个特定的非利定突变体的约氏嗜纤维菌有缺陷， 一种新型磺脂的生物合成途径， 非利定表型可以通过加入 适当的代谢前体（半胱氨酸）的培养基。 该项目是对这一开创性发现的生物化学后续研究， 并有望真正破译 参与滑动机制的细菌分子。