10 documents found, page 1 of 1
Screening and in silico characterization of prophages in Helicobacter pylori cl...
Ferreira, Rute Vanessa Novais; Pinto, Graça; Presa, Eva; Oleastro, Mónica; Silva, Catarina; Vieira, Luís; Sousa, Cláudia Sofia CunhaThe increase of antibiotic resistance calls for alternatives to control Helicobacter pylori, a Gram-negative bacterium associated with various gastric diseases. Bacteriophages (phages) can be highly effective in the treatment of pathogenic bacteria. Here, we developed a method to identify prophages in H. pylori genomes aiming at their future use in therapy. A polymerase chain reaction (PCR)-based technique test...
Advances on diagnosis of Helicobacter pylori infections
Sousa, Cláudia Sofia Cunha; Ferreira, Rute Vanessa Novais; Santos, Sílvio Roberto Branco; Azevedo, Nuno F.; Melo, Luís Daniel RodriguesThe association of Helicobacter pylori to several gastric diseases, such as chronic gastritis, peptic ulcer disease, and gastric cancer, and its high prevalence worldwide, raised the necessity to use methods for a proper and fast diagnosis and monitoring the pathogen eradication. Available diagnostic methods can be classified as invasive or non-invasive, and the selection of the best relies on the clinical cond...
Screening and in silico characterization of prophages in Helicobacter pylori ge...
Ferreira, Rute Vanessa Novais; Sousa, Cláudia Sofia Cunha; Presa, Eva; Pires, Diana Priscila Penso; Oleastro, Mónica; Azeredo, Joana; Figueiredo, CéuTemperate bacterio(phages) play an important role on the evolution of pathogenic bacteria. Nevertheless, information on their role in Helicobacter pylori (an important gastric pathogen bacterium) is scarce. The present study developed a workflow for the identification of prophages in Portuguese H. pylori clinical strains, proposing the use of a new PCR-based screening method. The genome of strains with differen...
H. pylori phages: from genome release to hope for use as therapy
Ferreira, Rute Vanessa Novais; Sousa, Cláudia Sofia Cunha; Presa, Eva; Pires, Diana Priscila Penso; Gonçalves, Raquel F. S.; Pinheiro, A. C.The increasing antibiotic-resistant Helicobacter pylori infections worldwide and the ineffectiveness of treatments led the World Health Organization to designate clarithromycin-resistant H. pylori as a high-priority bacterium for antibiotic research and development. (Bacterio)phages, viruses that infect bacteria, showing effectiveness in the treatment of pathogenic bacteria, could be a promising alternative str...
Characterization and genomic analysis of a new phage infecting Helicobacter pylori
Ferreira, Rute Vanessa Novais; Sousa, Cláudia Sofia Cunha; Gonçalves, Raquel; Pinheiro, A. C.; Oleastro, Mónica; Wagemans, Jeroen; Lavigne, RobHelicobacter pylori, a significant human gastric pathogen, has been demonstrating increased antibiotic resistance, causing difficulties in infection treatment. It is therefore important to develop alternatives or complementary approaches to antibiotics to tackle H. pylori infections, and (bacterio)phages have proven to be effective antibacterial agents. In this work, prophage isolation was attempted using H. py...
A novel Helicobacter pylori phage to combat gastric infections: first character...
Ferreira, Rute Vanessa Novais; Sousa, Cláudia Sofia Cunha; Gonçalves, Raquel F. S.; Pinheiro, A. C.; Oleastro, Mónica; Azeredo, Joana; Figueiredo, CéuHelicobacter pylori, a Gram-negative microaerophilic bacterium in a spiral shape, is recognized as an etiological agent of active chronic gastritis and contributes to peptic ulceration1. Furthermore, some studies associate it to development of gastric carcinoma2. Currently, treatment of H. pylori is performed with conventional antibiotics that in addition to the several side effects, increase the appearance of ...
Elucidating morphology of bacterial cells from complementary imaging by electro...
Petrovykh, Dmitri Y.; Silva, A. R.; Sousa, Cláudia Sofia Cunha; Exner, Daniela; Schwaiger, Ruth; Alves, M. M.; Pereira, LucianaWhen bacterial cells are imaged using vacuum-based high-resolution microscopy techniques, an important consideration is minimizing artifacts, which can arise from sample preparation protocols or from imaging conditions [1,2]. Commonly encountered artifacts include damage to the relatively fragile cells due to sample preparation, vacuum conditions, or high-energy imaging beams. We report on resolving a less comm...
Induction and initial characterization of a new Helicobacter pylori prophage
Ferreira, Rute Vanessa Novais; Sousa, Cláudia Sofia Cunha; Presa, Eva; Pires, Diana Priscila Penso; Mónica Oleastro; Azeredo, Joana; Figueiredo, CéuHelicobacter pylori is a Gram-negative bacterium that colonizes the stomach and it is considered one of the major human pathogens. Current treatments include a set of antibiotics with decreasing eradication rates, mainly due to the increase in the appearance of antibiotic-resistant strains. Bacterio(phages) have emerged in recent years as an effective alternative to fight bacterial infections. For therapeutic p...
Comparison of bioinformatics tools to predict the presence of prophages in Heli...
Ferreira, Rute Vanessa Novais; Sousa, Cláudia Sofia Cunha; Presa, Eva; Pires, Diana Priscila Penso; Oleastro, Mónica; Azeredo, Joana; Figueiredo, CéuBacterio(phages) are specific viruses for bacteria, being their natural enemies. When the genome of a phage is integrated into the host bacterial genome, it is named prophage. These are a latent form of phages, in which the viral genes can increase the virulence and/or fitness characteristics of the host. This life cycle - lysogenic - does not cause the bacterial cell to rupture. Prophages have already been ide...
Helicobacter pylori prophages: screening, detection, induction and potential th...
Ferreira, Rute Vanessa Novais; Sousa, Cláudia Sofia Cunha; Presa, Eva; Pires, Diana Priscila Penso; Oleastro, Mónica; Azeredo, Joana; Figueiredo, CéuHelicobacter pylori is a microaerophilic bacterium that chronically infects the human gastric mucosa. Infections caused by this pathogen are difficult to treat, mainly due to the increased resistance of this species to conventional antibiotics. Therefore, it is important to develop antibiotic alternative or complementary approaches to tackle H. pylori infections. Bacterio(phages) have proven to be efficient ant...