中文摘要：

Uropathogenic Escherichia coli (UPEC ) 是人的尿道感染(UTI ) 的最普通的原因的有机体。几个 UPEC 毒力因素被识别了，但是更多还有待于被发现。我们以前在用一种镇压减少性的杂交技术的 UPEC 紧张 132 识别了新奇 789-bp-long DNA 碎片(命名 R049 ) 。在现在的学习，我们使用了染色体去伸长这碎片到的顺序获得整个基因顺序并且在产生保护的免疫检验了这个基因产品的角色。通过生物信息的分析，我们预言这基因是 1311-bp 打开读的框架(ORF ) ，我们它指明了 ORFR049 (GenBank 就职号码：EF488001 ) 。我们进一步通过 IPTG 正式就职和镍亲密关系层析构造了一个原核生物的表达式系统表示完整的 recombinant R049 蛋白质并且孤立并且净化蛋白质。用净化的蛋白质产生的老鼠 immunosera，我们由西方的弄污在野类型的紧张 UPEC132 证实了自然表示和蛋白质的外部膜本地化。作为一个疫苗的候选人测试这蛋白质的潜力，我们在通过尿道与 UPEC132 质问他们前与 recombinant 蛋白质使老鼠免疫。结果与控制组相比在免疫组的尿和肾显示出显著地减少的细菌的殖民。然而，肾的病理学的损坏的度显著地没在使免疫的老鼠被改进。我们的学习识别了能对 UTI 产生保护的免疫的 UPEC 的新奇基因。这新奇基因提供一个有希望的新疫苗的候选人。

英文摘要：

Uropathogenic Escherichia coli （UPEC） is the most common causative organism of human urinary tract infection （UTI）. Several UPEC virulence factors have been identified, but more are yet to be found. We previously identified a novel 789-bp-long DNA fragment （named R049） in UPEC strain 132 using a suppressive subtractive hybridization technique. In the present study, we used genome walking to elongate the sequence of this fragment to obtain the whole gene sequence and examined the role of this gene product in generating protective immunity. Through bioinformatic analysis, we predicted that this gene is a 1311-bp open reading frame （ORF）, which we designated ORFR049 （GenBank accession No.： EF488001）. We further constructed a prokaryotic expression system to express full recombinant R049 protein and isolated and purified the protein through IPTG induction and nickel affinity chromatography. Using mouse immunosera generated by the purified protein, we confirmed the natural expression and outer membrane localization of the protein in wild-type strain UPEC132 by Western blotting. To test the potential of this protein as a vaccine candidate, we immunized mice with the recombinant protein before challenging them with UPEC132 through the urinary tract. The results showed significantly reduced bacterial colonization in the urine and kidneys of the immunization group compared with the control group. However, the degree of renal pathological damage was not significantly improved in the immunized mice. Our study has identified a novel gene of UPEC which can generate protective immunity against UTI. This novel gene provides a promising new vaccine candidate.