Neisseria gonorrhoeae TbpA functional analysis and inhibition

淋病奈瑟菌TbpA功能分析及抑制

• 批准号: 9312227
• 负责人: Devin Cash
• 金额: $ 2.91万
• 依托单位: VIRGINIA COMMONWEALTH UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-08-25 至 2018-05-12
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9312227
• 关键词: Abscess; Active Sites; Affinity; Alanine; Amino Acid Sequence; Antibiotic Resistance; Antibiotics; Antibodies; Antibody Response; Bacteria; Binding; Binding Sites; Biological Assay; Cells; Complex; Crystallization; Disease; Dot Immunoblotting; Drug Targeting; Drug resistance; Dysuria; Ectopic Pregnancy; Electrostatics; Environment; Epitopes; Gender; Genital system; Glycoproteins; Goals; Gonococcal Transferrin Receptor; Gonorrhea; Growth; Human; Immunity; Immunize; Incentives; Individual; Infection; Infection prevention; Infertility; Interruption; Investigation; Iron; Lipoproteins; Liquid substance; Measures; Membrane; Methods; Molecular; Molecular Conformation; Morbidity - disease rate; Mus; Mutation; Neisseria gonorrhoeae; Neisseria meningitidis; Nutrient; Pelvic Inflammatory Disease; Peptides; Phase; Play; Process; Property; Proteins; Publishing; Radiolabeled; Research; Resistance; Role; Serum; Sexually Transmitted Agents; Sexually Transmitted Diseases; Site; Site-Directed Mutagenesis; Solid; Source; Structure; Structure-Activity Relationship; Surface; Symptoms; System; TFRC gene; Tertiary Protein Structure; Therapeutic; Transferrin; Vaccines; Woman; Work; bactericide; base; chronic pelvic pain; combat; drug development; experimental study; human male; immunogenicity; men; mutant; new therapeutic target; novel therapeutics; pathogen; prevent; public health relevance; receptor; three dimensional structure; two-dimensional; uptake; vaccine development

DESCRIPTION (provided by applicant): Neisseria gonorrhoeae is the causative agent of the sexually transmitted infection gonorrhea. Genital gonorrhea is common in both genders, but has significant morbidity for women who are more frequently asymptomatically infected. Gonococcal infection in women has a range of symptoms that starts with dysuria and discharge and can end in conditions including pelvic inflammatory disease, internal abscess, ectopic pregnancy, or infertility. Infected individuals do not develop protective immunity, and the bacteria are rapidly developing antibiotic resistance. It is conceivable that soon we will not have an effective way to treat gonococcal infection. This issue has resulted in an increased incentive to develop a vaccine to prevent gonococcal disease. This study seeks to add to the field by exploring gonococcal properties that can be exploited for human vaccines or therapies. Interestingly, this pathogen has evolved to exclusively infect humans. In so doing, it has adapted unique methods of obtaining nutrients, including hijacking human proteins to acquire the essential nutrient iron. The gonococcal transferrin-iron acquisition system is composed of an integral, outer-membrane, TonB dependent transporter (TbpA), and a surface exposed lipo-protein (TbpB). This system is an ideal target for vaccine and drug development because it is plays a role in bacterial essential nutrient uptake, it is surface exposed, and the protein sequences are well conserved across strains. Previous studies have shown that gonococci lacking the transferrin iron acquisition system are incapable of initiating infection in human males. In addition, whole protein and epitope specific vaccine formulations derived from these proteins have shown growth inhibitory and bactericidal properties. Recently, crystal structures have been solved for TbpA and TbpB from the closely related pathogen Neisseria meningitidis. With a high level of sequence conservation between these two species, these crystals have been used to predict the three dimensional structure for the gonococcal proteins. This new information dramatically enhances the ability to target Tbp functional domains, which has significantly moved this field forward. This study will employ site specific mutagenesis of surface exposed loops of TbpA to assess key structure- function relationships in its interactions with human transferrin. In addition, several surface exposed loop peptides will be synthesized and will be used to immunize mice. The original peptides and the resulting sera will independently be characterized for their ability to interfere with TbpA-transferrin interactions. The goals of this study are to contribute to the understanding of how this receptor complex functions and to determine optimal targets for vaccine and drug development, such that new therapies can be developed for gonococcal infection before current treatments are rendered obsolete by acquired antibiotic resistance.

描述（由申请人提供）：淋病奈瑟氏菌是性传播感染淋病的病因。生殖器淋病在两种性别中都是常见的，但对于更常见于偶像感染的女性，均具有明显的发病率。女性的淋球菌感染具有一系列症状，这些症状始于排尿和出院，并且可以在包括骨盆炎症性疾病，内部脓肿，异位妊娠或不育的情况下结束。受感染的个体不发展保护性免疫，细菌正在迅速发展抗生素耐药性。可以想象，很快我们将没有一种有效的方法来治疗淋球菌感染。这个问题导致增加了开发疫苗以预防淋球菌疾病的动力。 这项研究试图通过探索可用于人类疫苗或疗法的淋球菌特性来增加现场。有趣的是，这种病原体已演变为仅感染人类。这样一来，它已经适应了获得营养的独特方法，包括劫持人蛋白来获得必需的营养铁。淋球菌转铁蛋白铁的采集系统由积分，外膜，TONB依赖性转运蛋白（TBPA）和表面暴露的脂肪蛋白（TBPB）组成。该系统是疫苗和药物开发的理想目标，因为它在细菌必需的营养摄取中起作用，表面暴露，并且蛋白质序列在跨菌株中均能很好地保守。先前的研究表明，缺乏转铁蛋白采集系统的淋球菌无力引发人类男性感染。此外，从这些蛋白质得出的全蛋白和表位特异性疫苗制剂显示出生长抑制和杀菌特性。最近，已经从密切相关的病原体脑膜炎的TBPA和TBPB求解了晶体结构。这些晶体在这两个物种之间具有高序列的保守性，已用于预测淋球菌蛋白的三维结构。这一新信息显着增强了针对TBP功能域的能力，这已经显着将该领域向前移动。 这项研究将采用TBPA表面暴露环的位点特异性诱变，以评估其与人转运蛋白相互作用的关键结构功能关系。此外，将合成几种表面暴露的环路肽，并将用于免疫小鼠。原始的肽和所得的血清将以干扰TBPA转移蛋白相互作用的能力而独立特征。这项研究的目标是有助于理解这种受体复合物功能如何并确定疫苗和药物开发的最佳靶标，以便在通过获得的抗生素耐药性使当前治疗过时之前，可以为淋球菌感染开发新的疗法。