PATHOGENIC POTENTIAL OF BLACK-PIGMENTED BACTEROIDES SPECIES

黑色拟杆菌种的致病潜力

• 批准号: 3854358
• 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/3854358
• 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.

口腔黑色素拟杆菌属已被明确 被认为是人类病原学中的重要微生物 牙周病、牙髓病变和某些严重口腔疾病 和口腔外软组织感染。 不仅拥有一定的 这些物种，例如牙龈拟杆菌和拟杆菌 中间体与口腔传染病密切相关 但最近的研究发现，物种内的某些菌株 对小鼠和豚鼠脓肿的毒性特别大 模型。 这种种内异质性在我们的研究中也很明显 最近的牙龈芽孢杆菌和中间芽孢杆菌的血清学研究。 本提案旨在定义和描述毒力 与黑色素感染相关的因素 拟杆菌属。 新鲜临床的体内致病潜力 分离株和我们自己的培养物保藏菌株将在 小鼠和豚鼠脓肿模型以及限生大鼠。 然后我们将确定表型和基因型特征 每个菌株均通过生化测试、气液测试 色谱法、光学和电子显微镜、血清学和 DNA-DNA 杂交。 然后这些特征将被关联起来 具有黑色拟杆菌的体内致病性 查明毒力相关因素。 由于环境起着 在确定细菌致病性表达中发挥关键作用， 我们将确定生长速率、铁限制、pH 值的影响， 和溶解氧含量对毒力表达的影响- 使用受控生长环境的相关因素 恒化器。 这些研究将极大地扩展有关该领域的可用信息。 人类口腔和口腔外感染的发病机制 黑色素拟杆菌属。 那么这些知识就可以 用于制定改进的预防和治疗措施 以控制这些感染。