Composition and Function of a Novel Consortial Endosymbiosis in the Shipworm Lyrodus pedicellatus.

船蛆 Lyrodus pedicellatus 中新型共生体的组成和功能。

• 批准号: 9982982
• 负责人: Daniel Distel
• 金额: $ 27.12万
• 依托单位: University of Maine
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-03-15 至 2004-02-29
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9982982&HistoricalAwards=false
• 关键词: Composition; Function; Novel; Consortial; Endosymbiosis

Enormous quantities of wood and other woody plant materials(including leaves, bark, shoots, stems and nuts) are produced annually inthe environment. In fact, cellulose, the major component of woodymaterials, is thought to be the most abundant biological material on earth.This remarkably strong and enduring molecule is a polymer of glucose(sugar) linked by a type of chemical bond that makes it indigestible tomost living organisms. Therefore, this rich source of food energy isavailable to only a few animals (e.g., termites and ruminants) that candigest cellulose with the aid of microbes living in their guts. Surprisingly, some marine animals can also digest wood. The mostimportant group is the wood-boring clams, commonly known as shipworms. Unliketermites and ruminants, these animals lack microorganisms in their gut.Instead they harbor enormous numbers of symbiotic bacteria inside the cellsof their gills. These bacteria fall into at least four closely relatedfamilies based on DNA analyses. The PIs have proposed that these bacteriaproduce cellulolytic enzymes that are transported from the gills to thegut. The purpose of this investigation is to explore the diversity anddistribution of symbiont types in the shipworm gills, to determine if eachsymbiont type contributes different cellulolytic enzymes, and to discoverhow the host uses these bacterial products to exploit cellulose as a foodsource. These investigations should result in the discovery of newcellulolytic enzymes that may have industrial applications in such areas aspaper and textile processing and fuel (ethanol) production via biomassconversion of agricultural wastes. These efforts will also help the PIs tounderstand the physiology of symbiotic bacterial infections that arebeneficial rather than harmful to their hosts.

环境中每年产生大量的木材和其他木本植物材料（包括叶子、树皮、芽、茎和坚果）。 事实上，纤维素是木质材料的主要成分，被认为是地球上最丰富的生物材料。这种非常坚固且持久的分子是葡萄糖（糖）的聚合物，通过一种化学键连接，使其无法被大多数生物体消化。 因此，只有少数动物（例如白蚁和反刍动物）能够借助肠道中的微生物消化纤维素，从而获得这种丰富的食物能量来源。令人惊讶的是，一些海洋动物也能消化木材。 最重要的类群是钻木蛤，俗称船蛆。 与白蚁和反刍动物不同，这些动物的肠道中缺乏微生物。相反，它们的鳃细胞内含有大量的共生细菌。 根据 DNA 分析，这些细菌至少分为四个密切相关的科。 PI 提出，这些细菌产生的纤维素分解酶从鳃转运到肠道。本研究的目的是探索船虫鳃中共生体类型的多样性和分布，以确定每种共生体类型是否贡献不同的纤维素分解酶，并发现宿主如何利用这些细菌产物来利用纤维素作为食物来源。 这些研究应该会发现新的纤维素分解酶，这些酶可能在纸张和纺织品加工以及通过农业废物的生物质转化生产燃料（乙醇）等领域具有工业应用。 这些努力还将帮助 PI 了解共生细菌感染的生理学，这些感染对宿主有益而不是有害。