MOLECULAR STUDIES OF T PALLIDUM TPRJ, TPRG, AND TPRE GENES

梅毒螺旋体是梅毒的病原体，梅毒是一种多阶段性传播疾病，是一个全球性的健康问题。该螺旋体的不可培养性阻碍了白螺旋体毒力决定因素和保护性免疫原的鉴定。虽然T. pallidum具有与革兰氏阴性菌相似的细胞结构，但其外膜含有罕见的免疫原性较差的蛋白质，其鉴定和功能仍然难以捉摸。利用TnphoA诱变技术，我们发现了一个编码牙周病原菌牙牙霉主要表面蛋白同源蛋白的基因（tprJ）。tprJ是一个多态多基因家族的成员，该家族编码12种蛋白质（TprA- L），可分为三个亚群。最近的研究显示了3亚群（tprJ、tprE和tprG）基因的异质性。我们假设依恋、入侵等功能活动。我们研究的长期目标是更好地了解3亚群tpr基因及其相应蛋白的变异。该项目的具体目标是：(1)检测白螺旋体tprJ、tprE和tprG基因内部或侧翼的核苷酸序列变化，从皮内感染家兔的机会中获得不同的时间点；(2)检测白僵菌中TprJ、TprE和TprG蛋白的表达，并评估兔IgG抗体对TprJ、TprE和TprG蛋白以及代表Tpr蛋白可变区和/或保守区肽的动力学；(4)确定用肽TprJ、TprE和TprG蛋白免疫家兔是否能保护白衣绦虫感染和/或选择表型变异；(5)评估在当地性病诊所就诊的梅毒患者临床标本中白衣绦虫TprJ、TprE和TprG基因的核苷酸序列变异。

Treponema pallidum is the etiologic agent of syphilis, a multistage sexually transmitted disease that is a global health problem. Identification of virulence determinants and protective immunogens of T. pallidum has been hindered by the non-cultivable nature of this spirochete. Although T. pallidum has a cellular architecture similar to Gram negative bacteria, its outer membrane contains rare, poorly immunogenic proteins whose identified and functions remain elusive. Using TnphoA mutagenesis, we identified a gene (tprJ) encoding a protein with homology to the major surface protein of T. denticola, a periodontal pathogen. The tprJ is a member of a polymorphic multi-gene family encoding 12 proteins (TprA- L), that are divided into three subgroups. Recent studies have shown heterogeneity in the subgroup 3 (tprJ, tprE, and tprG) genes. We hypothesize that functional activities such as attachment, invasion, etc. The long-term goal of our studies is to develop a better understanding of variation of the subgroup 3 tpr genes and their corresponding proteins. The specific aims for the project are: (1) To detect nucleotide sequence variations within or flanking the tprJ, tprE, and tprG genes of T. pallidum obtained a various timepoints from chances of intradermally infected rabbits; (2) To examine expression of the TprJ, TprE and TprG proteins in T. pallidum and to assess the kinetics of the rabbit IgG antibodies to the TprJ, TprE and TprG proteins and to peptides representing the variable and/or conserved regions of the Tpr proteins; (4) To determine if immunization of rabbits with the TprJ, TprE, and TprG proteins of peptide protects against infection with T. pallidum and/or selects for phenotypic variants and (5) To evaluate nucleotide sequence variability of the tprJ, tprE, and tprG genes of T. pallidum in clinical specimens from syphilis patients attending local STD clinics.