77 株临床分离的耐阿莫西林幽门螺杆菌与 77 株阿莫西林敏感株青霉素结合蛋白 1A 特定突变的比较。

Specific mutations of penicillin-binding protein 1A in 77 clinically acquired amoxicillin-resistant Helicobacter pylori strains in comparison with 77 amoxicillin-susceptible strains.

机构信息

Department of Internal Medicine, Seoul National University Bundang Hospital, Seongnam, South Korea.

Department of Internal Medicine, Kyungpook National University Hospital, Daegu, South Korea.

出版信息

Helicobacter. 2017 Dec;22(6). doi: 10.1111/hel.12437. Epub 2017 Aug 25.

DOI:10.1111/hel.12437

PMID:28840971

Abstract

BACKGROUND

Amoxicillin (Amx) is one of the most important antibiotics for eradication of Helicobacter pylori (H. pylori). Main determinants of genetically stable Amx resistance are mutations in the C-terminus of penicillin-binding protein 1A (pbp1A). However, contribution of individual mutation remains unclear.

METHODS

77 Amx-resistant (Amx ) and 77 Amx-susceptible (Amx ) H. pylori strains were isolated from gastric tissues, and DNA sequencing was performed to compare C-terminus sequences of pbp1A gene between Amx and Amx strains. Natural transformation of these mutated genes into amoxicillin-susceptible strains was performed.

RESULTS

Among many mutations in pbp1A, D479E (OR: 37.4, 95% CI: 5.53-252.49, P < .001), and T593 mutation (OR: 32.0, 95% CI: 4.04-252.86, P < .001) independently contributed to Amx resistance in H. pylori strains. In the transformation experiment, T593 mutations were identified in their transformants showing Amx resistance. However, PCR product of D479E was not inserted into recipient (ATCC 43504) resulting in transformation failure.

CONCLUSION

Amx resistance is associated with various substitutions in pbp1A and T593 mutation contributes to Amx resistance of H. pylori.

摘要

背景

阿莫西林（Amx）是根除幽门螺杆菌（H. pylori）的最重要抗生素之一。青霉素结合蛋白 1A（pbp1A）C 末端的突变是导致基因稳定的 Amx 耐药的主要决定因素。然而，个别突变的贡献仍不清楚。

方法

从胃组织中分离出 77 株 Amx 耐药（Amx）和 77 株 Amx 敏感（Amx）H. pylori 菌株，对 pbp1A 基因 C 末端序列进行 DNA 测序，比较 Amx 和 Amx 菌株之间的序列。将这些突变基因自然转化为 Amx 敏感株。

结果

在 pbp1A 中的许多突变中，D479E（OR：37.4，95%CI：5.53-252.49，P<.001）和 T593 突变（OR：32.0，95%CI：4.04-252.86，P<.001）独立导致 H. pylori 菌株对 Amx 的耐药性。在转化实验中，在表现出 Amx 耐药性的转化子中发现了 T593 突变。然而，D479E 的 PCR 产物未插入受体（ATCC 43504），导致转化失败。