PATHOGENIC POTENTIAL OF BLACK-PIGMENTED BACTEROIDES SPECIES

黑色拟杆菌种的致病潜力

• 批准号: 3875385
• 负责人: JOSEPH J ZAMBON
• 金额: --
• 依托单位: STATE UNIVERSITY OF NEW YORK AT BUFFALO
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/3875385
• 关键词: Bacteroides gingivalis; bacterial antigens; bacterial pigment; disease /disorder model; ferriheme; gene expression; genetic strain; germ free condition; guinea pigs; laboratory mouse; laboratory rat; lipopolysaccharides; membrane activity; microorganism classification; microorganism genetics; microorganism metabolism; oral bacteria; oxygen consumption; pathologic process; peptidases; periodontium disorder; ribosomal RNA; virulence

The oral black-pigmented Bacteroides species have been clearly implicated as important microorganisms in the etiology of human periodontal disease, endodontic lesions, and certain severe oral and extra-oral soft tissue infections. Not only have certain of these species such as Bacteroides gingivalis and Bacteroides intermedius been strongly associated with oral infectious disease but recent studies find that certain strains within species are particularly virulent in the mouse and the guinea pig abscess models. This intra-species heterogeneity is also evident in our recent serological studies of B. gingivalis and B. intermedius. The present proposal seeks to define and characterize virulence factors associated with infections due to black-pigmented Bacteroides. The in vivo pathogenic potential of fresh clinical isolates and our own culture collection strains will be examined in the mouse and guinea pig abscess models and in gnotobiotic rats. We will then determine the phenotypic and genotypic traits of each strain by means of biochemical tests, gas-liquid chromatography, light and electron microscopy, serology, and DNA-DNA hybridization. These traits will then be correlated with in vivo pathogenicity of the black-pigmented Bacteroides to pinpoint virulence-associated factors. Since environment plays a key role in determining the expression of bacterial pathogenicity, we will determine the effect of growth rate, iron limitation, pH, and dissolved oxygen content on the expression of virulence- associated factors using the controlled growth environment of the chemostat. These studies will greatly expand the available information on the pathogenesis of human oral and extra-oral infections caused by the black-pigmented Bacteroides. This knowledge can then be used to formulate improved preventive and therapeutic measures for the control of these infections.

口腔黑色素拟杆菌种已被明确 作为重要的微生物在人类病原学中的作用 牙周病、牙髓病和某些严重的口腔疾病 和口腔外软组织感染。 不仅有一定的 这些物种如牙龈拟杆菌和类杆菌 中间肌与口腔传染病密切相关 但最近的研究发现， 在老鼠和豚鼠脓肿中特别致命 模型 这种物种内的异质性在我们的研究中也很明显。 B的血清学研究进展牙龈炎和B.中间体 本提案旨在定义和描述毒性 与黑色色素沉着引起的感染相关的因素 拟杆菌 新鲜的临床病原体的体内致病潜力 分离株和我们自己的培养物收集菌株将在 小鼠和豚鼠脓肿模型和gnotobiotic大鼠。 然后，我们将确定表型和基因型性状的 每种菌株通过生化试验，气液 色谱法、光学和电子显微镜、血清学，以及 DNA-DNA杂交。 这些特征将与 与黑色素拟杆菌的体内致病性， 查明与毒性相关的因素。 由于环境起着 决定细菌致病性表达的关键作用， 我们将确定生长速率、铁限制、pH值 和溶解氧含量对毒力表达的影响- 相关因素，使用受控的生长环境， 恒化器 这些研究将极大地扩展关于 引起的人类口腔和口腔外感染的发病机制 黑色拟杆菌。 这些知识可以 用于制定更好的预防和治疗措施 来控制这些感染。