Differentially expressed genes in response to amoxicillin in Helicobacter pylori analyzed by RNA arbitrarily primed PCR.
ABSTRACT 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.
- SourceAvailable from: Jeong-Heon Cha[Show abstract] [Hide abstract]
ABSTRACT: The ability of clinicians to wage an effective war against many bacterial infections is increasingly being hampered by skyrocketing rates of antibiotic resistance. Indeed, antibiotic resistance is a significant problem for treatment of diseases caused by virtually all known infectious bacteria. The gastric pathogen Helicobacter pylori is no exception to this rule. With more than 50% of the world's population infected, H. pylori exacts a tremendous medical burden and represents an interesting paradigm for cancer development; it is the only bacterium that is currently recognized as a carcinogen. It is now firmly established that H. pylori infection is associated with diseases such as gastritis, peptic and duodenal ulceration and two forms of gastric cancer, gastric adenocarcinoma and mucosa-associated lymphoid tissue (MALT) lymphoma. With such a large percentage of the population infected, increasing rates of antibiotic resistance are particularly vexing for a treatment regime that is already fairly complicated; treatment consists of two antibiotics and a proton pump inhibitor. To date, resistance has been found to all primary and secondary lines of antibiotic treatment as well as to drugs used for rescue therapy.Current Drug Therapy 09/2008; 3(3):190-203.
- [Show abstract] [Hide abstract]
ABSTRACT: Pristine microbial mats from Camargue salterns (France)maintained in microcosm were contaminated by Erika fueloil in order to identify gene sequences induced in responseto heavy fuel oil contamination. The differential displayapproach was adapted to detect differentially expressedmRNA in complex bacterial communities. Among the sixdifferentially expressed (DD) cDNA fragments isolated,one was identified and associated with an ABC-type effluxpump. A second DD-fragment was related to a conservedhypothetical protein found in many different bacterial species.Despite differentially expressed fragments could notbe clearly identified, this study reveals new perspectivesfor the improvement of our knowledge on the response ofmicrobial community after petroleum contamination.Journal of Microbial & Biochemical Technology. 01/2009;
- [Show abstract] [Hide abstract]
ABSTRACT: Helicobacter pylori (H. pylori) antibiotic resistance is the main factor affecting the efficacy of the current eradicating therapies. The aim of this editorial is to report on the recent information about the mechanisms accounting for the resistance to the different antibiotics currently utilized in H. pylori eradicating treatments. Different mechanisms of resistance to clarithromycin, metronidazole, quinolones, amoxicillin and tetracycline are accurately detailed (point mutations, redox intracellular potential, pump efflux systems, membrane permeability) on the basis of the most recent data available from the literature. The next hope for the future is that by improving the knowledge of resistance mechanisms, the elaboration of rational and efficacious associations for the treatment of the infection will be possible. Another auspicious progress might be the possibility of a cheap, feasible and reliable laboratory test to predict the outcome of a therapeutic scheme.World journal of gastrointestinal pathophysiology. 06/2011; 2(3):35-41.