ESSENTIAL ROLE OF UREASE IN PATHOGENESIS OF GASTRITIS INDUCED BY HELICOBACTER-PYLORI IN GNOTOBIOTIC PIGLETS
ESSENTIAL ROLE OF UREASE IN PATHOGENESIS OF GASTRITIS INDUCED BY HELICOBACTER-PYLORI IN GNOTOBIOTIC PIGLETS
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DOI：
10.1128/iai.59.7.2470-2475.1991
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发表时间：
1991-07-01
影响因子：
3.1
通讯作者：
KRAKOWKA, S
中科院分区：
文献类型：
--
作者：
EATON, KA;BROOKS, CL;KRAKOWKA, S
利用N-甲基-N'-硝基-N-亚硝基胍制备了弱脲酶活性的幽门螺杆菌突变株。 突变体的脲酶活性（每分钟每μg细菌蛋白0.036+/-0.009nmol尿素）是亲本菌株（每分钟每μg细菌蛋白8.20+/-2.30nmol尿素）的0.4%。 突变体与亲本菌株在其他方面无法区分。 两者都表现出显着的过氧化氢酶和氧化酶活性，并且都产生空泡细胞毒素。 两个菌株的限制性内切酶和十二烷基硫酸钠-聚丙烯酰胺凝胶电泳（SDS-PAGE）图谱和超微结构相同。 通过在软琼脂中铺展和直接显微镜检查来评估，突变体是完全能动的。 突变体和亲本菌株的生长速率、菌落大小和形态是相同的。 用突变体或亲本菌株攻击 17 只无菌小猪，并在攻击后 3 或 21 天处死。 对胃组织进行组织学检查并培养幽门螺杆菌。 在接受亲代菌株攻击的七只小猪中，全部都被感染。 接受脲酶阴性菌株攻击的 10 头仔猪中，均未检测到幽门螺杆菌。 在用亲本品系攻击的所有七只仔猪中都存在淋巴滤泡性胃炎，但在用脲酶阴性品系攻击的仔猪中没有一头出现淋巴滤泡性胃炎。 这些结果表明显着的脲酶活性对于幽门螺杆菌的定植至关重要。
A mutant strain of Helicobacter pylori with weak urease activity was created by using N-methyl-N'-nitro-N-nitrosoguanidine. The urease activity of the mutant (0.036 +/- 0.009 nmol of urea per mu-g of bacterial protein per min) was 0.4% of that of the parental strain (8.20 +/- 2.30 nmol of urea per mu-g of bacterial protein per min). The mutant was otherwise indistinguishable from the parental strain. Both demonstrated prominent catalase and oxidase activities, and both produced vacuolating cytotoxin. Restriction endonuclease and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) patterns and ultrastructure were identical for the two strains. The mutant was fully motile, as evaluated by spreading in soft agar and by direct microscopic examination. Growth rate and colony size and morphology were identical for the mutant and parental strains. Seventeen gnotobiotic piglets were challenged with either the mutant or the parental strain and sacrificed 3 or 21 days after challenge. Gastric tissue was examined histologically and cultured for H. pylori. Of seven piglets challenged with the parental strain, all became infected. H. pylori was not recovered from any of 10 piglets challenged with the urease-negative strain. Lymphofollicular gastritis was present in all seven piglets challenged with the parental strain but in none of the piglets challenged with the urease-negative strain. These results suggest that prominent urease activity is essential for colonization by H. pylori.