ANALYSIS OF POLYHYDROXYALKANOATE INCLUSION BIOGENESIS

多羟基链烷酸酯包合物生物生成分析

• 批准号: 7960127
• 负责人: Douglas Dennis
• 金额: $ 8.17万
• 依托单位: UNIVERSITY OF LOUISVILLE
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-08-22 至 2010-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7960127
• 关键词: Atomic Force Microscopy; Biogenesis; Biomedical Research; Carbon; Cell membrane; Computer Retrieval of Information on Scientific Projects Database; Cytoplasm; Electron Microscopy; Family; Funding; Genetic; Goals; Grant; Institution; Membrane; Modeling; Movement; Nitrogen; Nutrient; Plastics; Polyesters; Polymers; Proteins; Research; Research Personnel; Resources; Source; Structure; Thick; United States National Institutes of Health; interest; periplasm

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The goal of this research is to elucidate the mechanism of polyhydroxyalkanoate inclusion biogenesis. Polyhydroxyalkanoates (PHAs) are bacterial polymers that are synthesized in inclusions when carbon levels are high and another essential nutrient, such as nitrogen is limited. There is considerable commercial interest in PHAs because they comprise a family of polyesters that can be formed into plastics that are biodegradable. Electron microscopy studies have been unable to resolve the structure of PHA inclusions and this has inhibited movement toward a cohesive model of inclusion biogenesis. Employing atomic force microscopy, we have determined that there are three layers of structure, an outer envelope that is the thickness of a membrane bilayer, a middle network layer, and an underlying crystalline lamellar layer. Genetic studies have indicated that the middle network is comprised at least partially of PhaP and that PhaP is likely to be translocated to the periplasm. Thus, it would appear that inclusion biogenesis may occur by movement of protein and/or proteins to the periplasm and budding through the cytoplasmic membrane into the cytoplasm, facilitating the acquisition of the cytoplasmic membrane as an envelope.

该子项目是利用该技术的众多研究子项目之一 资源由 NIH/NCRR 资助的中心拨款提供。子项目和 研究者 (PI) 可能已从 NIH 的另一个来源获得主要资金， 因此可以在其他 CRISP 条目中表示。列出的机构是 对于中心来说，它不一定是研究者的机构。 本研究的目的是阐明聚羟基脂肪酸酯包合物生物发生的机制。 聚羟基脂肪酸酯 (PHA) 是一种细菌聚合物，当碳含量较高且另一种必需营养素（例如氮）有限时，内含物中会合成这种聚合物。 PHA 具有相当大的商业兴趣，因为它们包含一系列聚酯，可以制成可生物降解的塑料。电子显微镜研究无法解析 PHA 内含物的结构，这抑制了内含物生物发生的内聚模型的发展。采用原子力显微镜，我们确定了三层结构，即双层膜厚度的外层、中间网络层和下面的结晶层状层。遗传学研究表明，中间网络至少部分由 PhaP 组成，并且 PhaP 很可能易位至周质。因此，看来包涵体生物发生可能是通过蛋白质和/或多种蛋白质移动到周质并通过细胞质膜出芽进入细胞质，从而促进获得细胞质膜作为包膜而发生的。