ENZYMOLOGY OF BACTERIAL CELL MEMBRANES

细菌细胞膜的酶学

• 批准号: 3124406
• 负责人: JOHN S ANDERSON
• 金额: $ 14.01万
• 依托单位: UNIVERSITY OF MINNESOTA
• 依托单位国家: 美国
• 财政年份: 1979
• 资助国家: 美国
• 起止时间: 1979-06-01 至 1991-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3124406
• 关键词: Micrococcaceae; bacteria; cell membrane; cell wall; enzyme mechanism; gel electrophoresis; ion exchange chromatography; lipopolysaccharides; mass spectrometry; membrane activity; membrane permeability; microorganism metabolism; peptidoglycan; radiotracer; teichoate; ultracentrifugation

The objective of this project is to study how the enzymes of the cytoplasmic membrane of Micrococcus luteus, a gram positive bacterium, effect the biosynthesis of teichuronic acid which is covalently linked to the peptidoglycan. A series of intermediates containing undecaprenyl phosphate as carrier lipid effect teichuronic acid biosynthesis by sequential elongation of the carbohydrate chain of teichuronic acid. Modified cell preparations will be used to determine if some of the intermediates can transfer the putative teichuronic acid chain to peptidoglycan. Concomitant peptidoglycan synthesis may also be required. Another objective is to isolate and chemically characterize the unique linkage region oligosaccharide which joins teichuronic acid to peptidoglycan. An enzymatic and chemical degradation scheme based on the presumed structure of the linkage region will be followed by purification. Methylation analysis, mass spectrometry and nuclear magnetic resonance spectroscopy will be used for characterization. The glycosyltransferase which is involved in teichuronic acid chain elongation will be purified so that the mechanism can be determined by which glucosyl residues are incorporated into the polymer with retention of anomeric configuration while the alternate residues of the polymer are incorporated with inversion of configuration. Teichuronidase, an enzyme which degrades teichuronic acid, will be isolated from an organism which can utilize teichuronic acid as growth substrate. Characterization of the enzyme will follow. Immunoelectron microscopy utilizing antibodies directed against teichuronic acid will be used to evaluate the location of teichuronic acid in the cell wall and sites of synthesis in the cytoplasmic membrane. Proteus myxofaciens, a gram negative bacterium, produces an extracellular gel which will be isolated and characterized by methylation analysis, mass spectrometry and nuclear magnetic resonance spectroscopy.

这个项目的目标是研究细胞中的酶是如何 革兰氏阳性菌黄微球菌胞质膜 对共价连接的替胡酸生物合成的影响 多肽聚糖。一系列含十一碳烯基的中间体 磷酸盐作为载体脂类对马兜铃酸生物合成的影响 替胡酸碳水化合物链的连续伸长。 修改后的细胞制剂将被用来确定一些 中间体可以将推定的teichuronic酸链转移到 多肽聚糖。随之而来的肽聚糖合成也可能是必需的。 另一个目标是分离独一无二的 连接替胡萝卜酸的连接区低聚糖 多肽聚糖。一种基于酶和化学降解的方案 在推测的连接区结构之后将进行纯化。 甲基化分析、质谱学和核磁共振 光谱学将用于表征。 与端粒酸链有关的糖基转移酶 延伸率将被提纯，以便通过以下方式确定其机制 哪些葡萄糖基残基被结合到聚合物中并保留 当聚合物的交替残基是 与构型反转结合在一起。 将分离Teichuronidase，一种降解Teichuronic酸的酶 来自一种可以利用替胡萝卜酸作为生长底物的有机体。 随后将对该酶进行表征。 利用针对Tichuronic的抗体的免疫电子显微镜 酸将用来评估替古酸在细胞中的位置 胞质膜中合成的壁和部位。 粘液变形杆菌是一种革兰氏阴性杆菌，产生一种胞外细菌。 该凝胶将被分离并通过甲基化分析、质量分析进行表征 光谱学和核磁共振光谱学。