Godoy Anita P O, Reis Fernanda C, Ferraz Lúcio F C, Gerrits Monique M, Mendonça Sergio, Kusters Johannes G, Ottoboni Laura M M, Ribeiro Marcelo L, Pedrazzoli José
Clinical Pharmacology and Gastroenterology Unit, São Francisco University Medical School, Braganca Paulista, SP, Brazil.
FEMS Immunol Med Microbiol. 2007 Jul;50(2):226-30. doi: 10.1111/j.1574-695X.2006.00209.x.
Because the molecular mechanism of amoxicillin resistance in Helicobacter pylori seems to be partially explained by several mutational changes in the pbp1A gene, the aim of the present study was to evaluate the gene expression pattern in response to amoxicillin in the Amx(R) Hardenberg strain using RNA arbitrarily primed PCR (RAP-PCR). In the experiments, c. 100 differentially expressed RAP-PCR products were identified using five arbitrary primers. The cDNAs that presented the highest levels of induction or repression were cloned and sequenced, and the sequences were compared with those present in databases using the blast search algorithm. The differential expression of the isolated cDNAs was confirmed by real-time PCR. The preliminary results showed that amoxicillin alters the expression of five cDNAs involved in biosynthesis, two involved with pathogenesis, four related to cell envelope formation, two involved in cellular processes, three related with transport and binding proteins, one involved with protein degradation, one involved with energy metabolism and seven hypothetical proteins. Further analysis of these cDNAs will allow a better comprehension of both the molecular mechanism(s) of amoxicillin resistance and the adaptative mechanism(s) used by H. pylori in the presence of this antibiotic.
由于幽门螺杆菌对阿莫西林耐药的分子机制似乎部分可由pbp1A基因的若干突变变化来解释，因此本研究的目的是使用RNA任意引物PCR（RAP-PCR）评估Amx（R）哈登贝格菌株中对阿莫西林产生反应的基因表达模式。在实验中，使用5种任意引物鉴定出约100种差异表达的RAP-PCR产物。对呈现出最高诱导或抑制水平的cDNA进行克隆和测序，并使用blast搜索算法将序列与数据库中存在的序列进行比较。通过实时PCR确认分离出的cDNA的差异表达。初步结果表明，阿莫西林改变了5种参与生物合成的cDNA、2种参与致病机制的cDNA、4种与细胞壁形成相关的cDNA、2种参与细胞过程的cDNA、3种与转运和结合蛋白相关的cDNA、1种参与蛋白质降解的cDNA、1种参与能量代谢的cDNA以及7种假定蛋白的表达。对这些cDNA的进一步分析将有助于更好地理解阿莫西林耐药的分子机制以及幽门螺杆菌在这种抗生素存在时所采用的适应性机制。
