Characterization of viridans group streptococci from endophthalmitis

眼内炎草绿色链球菌的特征

• 批准号: 10245289
• 负责人: MARY E MARQUART
• 金额: $ 22.55万
• 依托单位: UNIVERSITY OF MISSISSIPPI MED CTR
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-09-01 至 2023-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10245289
• 关键词: Amino Acid Sequence; Antibiotics; Bacteria; Bacterial Proteins; Bacteriology; Bioinformatics; Case Study; Clinical; Collection; Deletion Mutagenesis; Development; Disease; Endophthalmitis; Enzymes; Erythrocytes; Etiology; Eye; Eye Infections; Future; Genbank; Gene Expression; Genes; Genetic; Genome; Genomics; Genus staphylococcus; Growth; Health; Heterogeneity; Horizontal Gene Transfer; Human; In Vitro; Infection; Injections; Investigation; Kinetics; Knowledge; Lead; Literature; Mining; Oligonucleotide Primers; Operative Surgical Procedures; Oral cavity; Organism; Oryctolagus cuniculus; Outcome; Pathogenesis; Patients; Peptide Hydrolases; Process; Prognosis; Proteins; Recombinant Proteins; Recombinants; Research; Resistance; Role; Sequence Analysis; Sheep; Streptococcus; Streptococcus Viridans Group; Streptococcus anginosus; Streptococcus gordonii; Streptococcus mitis; Streptococcus mutans; Streptococcus oralis; Streptococcus sanguis; Structure of retinal pigment epithelium; Substrate Specificity; Testing; Translating; Trauma; Variant; Virulence; Virulence Factors; Virulent; Visual; Vitreous humor; bacterial endophthalmitis; comparative; cytokine; epidemiology study; experimental study; extracellular; genome analysis; genome sequencing; in vivo; inhibitor/antagonist; normal microbiota; oral commensal; oral pathogen; pan-genome; protein degradation; protein purification; therapeutic development; therapy development; transcriptome; transcriptome sequencing; transcriptomics; whole genome

Project Summary/Abstract The viridans streptococci are classically considered oral commensals with cariogenic potential; however, these bacteria are also listed among the most common species that cause bacterial endophthalmitis. Exogenous bacterial endophthalmitis can occur following trauma, ocular surgery, or ocular injections. Antibiotics are used to treat this disease, however, antibiotics are only able to kill the bacteria and do not ameliorate the damage to the eye. Streptococcal species in particular are associated with very poor visual outcomes; despite treatment, evisceration or enucleation commonly occur. The immediate objective of this application is to characterize endophthalmitis strains of the viridans streptococci and identify their virulence factors. This objective is intended to initiate study into the broader, long-term objectives of determining the mechanisms of pathogenesis of this important group of species and identify potential targets for future therapies. Two major aims are proposed: 1) to investigate the role of bacterial protease HtrA in endophthalmitis and determine its vitreous and bacterial protein substrates, and 2) to analyze the pangenome and virulence transcriptome of endophthalmitis- causing strains. The first aim will be tested by function analysis of recombinant HtrA variants cloned from the viridans strains and by deletion mutagenesis of htrA from htrA-positive strains, as well as genetic addition of htrA to htrA-negative strains. The second aim will employ whole genome sequencing of 21 strains followed by bioinformatics pangenome analysis to identify conserved genes across the collection, and RNA-seq in vivo and in vitro to determine the virulence transcriptome of this group of species. Accomplishment of these aims will springboard the identification of key factors involved in ocular infection by these species. This research is expected to benefit patient ocular health in the long-term because the knowledge to be gained can aid future therapeutic development.

项目摘要/摘要 Viridans链球菌在经典上被认为具有致癌性的口服共性。但是，这些 细菌也被列为引起细菌性内嗜性的最常见物种之一。外源 创伤，眼部手术或眼部注射后，可能发生细菌性内脑炎。使用抗生素 然而，为了治疗这种疾病，抗生素只能杀死细菌，并且不会改善对 眼睛。特别是链球菌物种与非常差的视觉结局有关。尽管有治疗 通常发生脱核或摘除。此应用的直接目的是表征 Viridans链球菌的内膜菌株并鉴定其毒力因子。这个目标是 旨在启动研究确定发病机理的更广泛的长期目标 在这一重要的物种中，并确定了未来疗法的潜在靶标。两个主要目的是 提议：1）研究细菌蛋白酶htra在内脑炎的作用，并确定其玻璃体和 细菌蛋白底物和2）分析内嗜性染色体的pangenome和毒力转录组 引起菌株。第一个目标将通过重组HTRA变体的功能分析来测试 Viridans菌株和通过HTRA阳性菌株的HTRA的缺失诱变，以及遗传添加 HTRA至HTRA阴性菌株。第二个目标将对21种菌株进行整个基因组测序，然后使用 生物信息学分析以鉴定整个集合中的保守基因以及体内RNA-seq 在体外确定这组物种的毒力转录组。这些目标的实现将 跳板鉴定这些物种涉及的眼部感染的关键因素。这项研究是 从长远来看，预计将使患者眼健康受益，因为要获得的知识可以帮助未来 治疗发展。