Analysis of pH dependent regulation in B. burgdorferi

伯氏疏螺旋体 pH 依赖性调节分析

• 批准号: 6646732
• 负责人: James A. Carroll
• 金额: $ 15.66万
• 依托单位: UNIVERSITY OF PITTSBURGH AT PITTSBURGH
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-04-01 至 2005-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6646732
• 关键词: Borrelia; DNA footprinting; Ixodes; Lyme disease; SDS polyacrylamide gel electrophoresis; acid base balance; affinity chromatography; arthropod borne communicable disease; bacteria infection mechanism; electroporation; environmental adaptation; flow cytometry; gel mobility shift assay; genetic regulation; green fluorescent proteins; mass spectrometry; matrix assisted laser desorption ionization; molecular cloning; molecular pathology; polymerase chain reaction; protein binding; proteomics; regulatory gene

DESCRIPTION (provided by applicant): Lyme disease is a multi-systemic disorder caused by Borrelia burgdorferi that spreads to mammals by the bite of an Ixodes tick. In the U.S. alone over 17,000 cases were reported in 2000, making it the number one reportable arthropod-borne infectious disease. In unfed, infected ticks the bacteria reside in the tick midgut, which has a pH/temperature of 8.0-8.4/23degreesC. During tick feeding and transmission the spirochetes experience a shift in pH/temperature from 8.0-8.4/23degreesC to 6.0- 7.4/35degreesC due to the influx of blood from the host. B. burgdorferi adapts to its new surroundings by altering the expression of different genes in response to environmental cues, such as changes in pH and temperature. We propose to delineate the molecular mechanisms that are involved in gene regulation in response to pH. Using affinity chromatography, mass spectroscopy and DNase I footprinting we propose to identify, characterize and inactivate the positive regulator of paralogous gene family 54 in B. burgdorferi. This gene family contains 13 genes that are located on linear plasmids. The role of these genes in the infection or adaptation process is unknown, but gene family members bba64, bba65, bba66, and bba73 are regulated by changes in pH and have been implicated in contributing to acute Lyme arthritis in model systems. By understanding how this bacterium is able to sense the environment and alter gene expression in response to changes in environmental cues, we hope to gain insight into i) the regulatory components necessary for adaptation and infection and ii) the role of pH regulation of target genes in mammalian pathogenesis.

描述（由申请人提供）：莱姆病是由Borrelia burgdorferi引起的一种多系统疾病，它被IXODES tick叮咬传播给哺乳动物。仅在美国，2000年就报告了超过17,000例病例，使其成为可报告的节肢动物传染病的第一大病例。在未染色的，感染的tick中，细菌位于tick中肠中，pH/温度为8.0-8.4/23greesc。在滴答喂食和传播过程中，由于宿主流血流血，螺旋体经历了pH/温度从8.0-8.4/23Degreesc转移到6.0- 7.4/35级。 B. burgdorferi通过响应环境线索（例如pH和温度的变化）来改变不同基因的表达来适应其新环境。我们建议描述响应于pH的基因调节所涉及的分子机制。使用亲和色谱法，质谱和DNase I足迹，我们建议识别，表征和失活B. burgdorferi中寄生基因家族的阳性调节剂54。该基因家族包含13个位于线性质粒上的基因。这些基因在感染或适应过程中的作用尚不清楚，但是基因家族成员BBA64，BBA65，BBA66和BBA73受pH的变化调节，并且与模型系统中的急性莱姆关节炎有关。通过了解该细菌如何能够感知环境并改变基因表达，以应对环境线索的变化，我们希望深入了解i）适应和感染所必需的调节成分以及ii）pH调节靶基因在哺乳动物发病机理中的作用。