Tsuda M, Karita M, Mizote T, Morshed M G, Okita K, Nakazawa T
Department of Microbiology, Yamaguchi University School of Medicine, Ube, Japan.
Eur J Gastroenterol Hepatol. 1994 Dec;6 Suppl 1:S49-52.
To investigate the involvement of urease in Helicobacter pylori colonization in the nude mouse stomach by using a genetically defined urease-negative mutant.
Through electroporation-mediated gene replacement, one of the urease genes of an H. pylori strain, CYP3401, was disrupted by insertion of a kanamycin-resistance determinant to construct a stable urease-negative mutant, HPT73. Southern analysis confirmed that gene replacement was achieved. The two isogenic strains were introduced into the stomachs of nude mice, and the number of H. pylori and the histological changes in the stomachs were investigated 1 or 4 weeks after the challenge. Gastritis was present in the CPY3401-challenged stomach, from which bacteria indistinguishable from CPY3401 were successfully recovered. In contrast, no gastritis was found in the HPT73-challenged stomach, and H. pylori was not recovered from these stomachs.
H. pylori urease is essential for colonization of the nude mouse stomach.
通过使用基因明确的脲酶阴性突变体，研究脲酶在幽门螺杆菌在裸鼠胃中定植过程中的作用。
通过电穿孔介导的基因置换，将卡那霉素抗性决定簇插入幽门螺杆菌菌株CYP3401的一个脲酶基因中，使其破坏，构建出稳定的脲酶阴性突变体HPT73。Southern分析证实基因置换成功。将这两个同基因菌株接种到裸鼠胃中，在接种后1周或4周，研究幽门螺杆菌数量及胃组织学变化。接种CPY3401的胃出现胃炎，从其中成功分离出与CPY3401无法区分的细菌。相比之下，接种HPT73的胃未发现胃炎，且未从这些胃中分离出幽门螺杆菌。
幽门螺杆菌脲酶对裸鼠胃的定植至关重要。
