PATHOGENESIS OF Helicobacter pylori IN GASTRIC DISEASES

幽门螺杆菌在胃病中的发病机制

• 批准号: 06670295
• 负责人: NAKAZAWA Teruko
• 金额: $ 1.34万
• 依托单位: YAMAGUCHI UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1994
• 资助国家: 日本
• 起止时间: 1994 至 1995
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-06670295/
• 关键词: H.pylori infection; urease; cyclodextrin; gene disruption; nude mouse model; proton-pump inhibitor; chemotaxis; persistent infection; ヘリコバクター・ピロリ; ヌードマウス

1.A low-serum medium containing beta-cyclodextrin for cultivation of Helicobacter pylori has been developed. (14)2.A urease-negative mutant was isolated by allelic exchange mutagenesis. The ureB gene cloned in E.coli was disrupted by the insertion of a Km^R gene, the resulting plasmid was introduced into H.pylori, and a Km^R transformant was obtained which had no urease activity. The wild-type and the mutant strains were indistinguishable from each other in the growth rate, motility, and cytotoxin production. On the other hand, acid resistance in vitro in the presence of urea was abolished in the mutant strain. The colonization ability of these strains was tested by challenging to the nude mouse stomach. After 1 week and 4 weeks the mouse stomach was taken and cut into half. The stomach challenged by the wild-type strain showed inflammation and the strain was recovered. On the other hand, the stomach challenged by the mutant strain did not showed inflammation, and no colonies appeared by cultivation. These results indicated that urease is essentila for colonization in the stomach. (150)3.By using an isogenic urease-negative mutant, it was proved that the antibacterial activity of lansoprazole against H.pylori is independent from its inhibitory activity on H.pylori urease. (30)4.A clone containing the whole urease operon was isolated from a H.pylori strain which showed good growth and high competence activity. To investigate the role of a urease-accesory gene, ureI,the gene was dirupted by allelic exchange mutagenesis. The resulting strain showed no urease activity, but produced the urease apoenzyme which was detected by monoclonal antibodies raised against UreA and UreB subunits. (65)5.H.pylori showed chemotaxis towards urea, urease inhibitor, bicarbonate ion, socium ion, some amino acid. The chemotactic activity was also observed with the urease-negative mutant, indicating that the chemotactic activty of H.pylori towards urea is independent from its urease. (40)

1.研制了一种含β-环糊精的幽门螺杆菌低血清培养基。（14）2.通过等位基因交换诱变分离到一个尿素酶阴性突变体。通过插入Km^R基因破坏大肠杆菌中克隆的ureB基因，将得到的质粒导入幽门螺杆菌，得到不具有尿素酶活性的Km^R质粒。野生型和突变株在生长速率、运动性和细胞毒素产生方面彼此难以区分。另一方面，在尿素的存在下，体外的耐酸性被废除的突变株。通过对裸鼠胃的攻击来测试这些菌株的定殖能力。1周和4周后，取出小鼠胃并切成两半。野生型菌株激发的胃显示炎症，菌株恢复。另一方面，用突变株攻击的胃没有显示炎症，培养时也没有菌落出现。这些结果表明，尿素酶是胃内定殖的必要条件。（150）3.通过使用尿素酶阴性的同基因突变体，证明兰索拉唑对幽门螺杆菌的抗菌活性不依赖于其对幽门螺杆菌尿素酶的抑制活性。（30）4.从一株生长良好、感受态活性高的幽门螺杆菌中分离到一个含有完整尿素酶操纵子的克隆。为了研究尿素酶辅助基因ureI的作用，通过等位基因交换突变使该基因断裂。所得到的菌株显示没有脲酶活性，但产生的尿素酶脱辅基酶，这是由针对UreA和UreB亚基的单克隆抗体检测。（65）5.幽门螺杆菌对尿素、尿素酶抑制剂、碳酸氢根离子、socium离子、某些氨基酸有趋化作用。在尿素酶阴性的突变体中也观察到了趋化活性，表明幽门螺杆菌对尿素的趋化活性与其尿素酶无关。（四十）

项目成果

Tsuda, M.: "A urease-negative mutant of Heiicobacter pylori constructed by allelic exchange mutagenesis lacks the ability to colonize the nude mouse stomach." Infect. Immun.62. 3586-3589 (1994)

Tsuda, M.：“通过等位基因交换诱变构建的幽门螺杆菌脲酶阴性突变体缺乏在裸鼠胃中定殖的能力。”

中澤晶子(分担): "Helicobacter pyloriの最新知見" 日本消化器病学会編、中山書店, 321 (12) (1995)

Akiko Nakazawa（撰稿人）：《幽门螺杆菌的最新发现》，日本胃肠病学会编，中山书店，321（12）（1995）

中澤晶子: "Helicobacter pyloriの細菌学的特徴" 最新医学. 50. 979-984 (1995)

Akiko Nakazawa：“幽门螺杆菌的细菌学特征”现代医学 50. 979-984 (1995)。

中澤晶子(分担): "Helicobacter pyloriの最新知見" 日本消化器病学会編、中山書店, 321(12) (1995)

Akiko Nakazawa（撰稿人）：“幽门螺杆菌的最新发现”，日本胃肠病学会编辑，中山书店，321（12）（1995）

Morshed, M. G.: "Growth medium containing cyclodextrin and low concentration of horse serum for cultivation of Helicfobacter pylori." Microbiol. Immunol.38. 897-900 (1994)

Morshed, M. G.：“含有环糊精和低浓度马血清的生长培养基，用于培养幽门螺杆菌。”