Helicobacter Pylori Strains Research Articles

Correlation Analysis between the Characteristics of Helicobacter pylori Resistance and the Antibiotic Use Density in a Hospital from 2012 to 2018.

Objective To explore the correlation between the resistance characteristics of Helicobacter pylori (HP) and antibiotic use density (AUD) in a hospital from 2012 to 2018. Methods HP strains isolated from Chinese PLA General Hospital from 2012 to 2018 were collected to analyze the drug resistance of clarithromycin, levofloxacin, amoxicillin, and metronidazole, and their correlation with the AUD of the outpatient department and inpatient department was analyzed, respectively. Results From 2012 to 2018, metronidazole-resistant strains accounted for the largest proportion, followed by clarithromycin and levofloxacin, and amoxicillin-resistant strains accounted for the least. In 2012–2018, the resistance rate of clarithromycin, levofloxacin, amoxicillin, and metronidazole has basically increased year by year; from 2012 to 2018, the highest outpatient AUD in a hospital was amoxicillin, followed by clarithromycin and levofloxacin, metronidazole was the lowest, and the inpatient AUD from high to low was levofloxacin, metronidazole, amoxicillin, and clarithromycin. The drug resistance rate of HP in the hospital from 2012 to 2018 was positively correlated with the AUD of clarithromycin (r = 0.884, P=0.017) and levofloxacin (r = 0.934, P=0.002) in the outpatient department. Conclusions Helicobacter pylori has the strongest resistance to metronidazole and the worst resistance to amoxicillin in the hospital from 2012 to 2018, being related to the intensity of clarithromycin and levofloxacin in the outpatient department. It may provide certain reference significance for the clinical treatment of Helicobacter pylori.

Correlation between clarithromycin resistance, virulence factors and clinical characteristics of the disease in Helicobacter pylori infected patients in Shahrekord, Southwest Iran

The purpose of this study was to determine the mutations associated with clarithromycin resistance in Helicobacter pylori strains isolated from biopsy samples that were collected from the endoscopic ward of Shahrekord Hajar teaching Hospital and also to study the frequency of virulence factor and their correlation and pathological findings with clarithromycin resistance during the years 2019–2020. In this cross-sectional descriptive study, 152 patients with Helicobacter pylori infection were considered, and then, two common A2142G and A2143G mutations in the 23SrRNA gene associated with resistance were analyzed by Real-time PCR (Taq man). The presence of vacA, iceA1, iceA2, cagA, babA2, and oipA virulence genes was investigated by PCR and electrophoresis in 8% polyacrylamide gel. Then, data were analyzed using the relevant statistical tests. In this study, the frequency of Helicobacter pylori was 76% and the frequency of mutant isolates was 57.2%. The frequencies of A2142G and A2143G point mutations were 42.1% and 28.3%. There was a significant correlation among oipA, vacA, and iceA1 virulence factors, type of disease, chronic inflammatory score, and glandular atrophy with the antibiotic resistance to clarithromycin. There was no significant correlation between the age and sex of the patients with antibiotic resistance. According to the results of this study, it seems that the use of clarithromycin to combat this bacterium should be limited.

Complete Genome Sequence of Helicobacter pylori Strain 3401, a Suitable Host for Bacteriophages KHP30 and KHP40.

ABSTRACTHelicobacter pylori 3401, isolated from a patient with duodenal ulcers in Japan, is susceptible to the bacteriophages KHP30 and KHP40. In this study, we report the complete genome sequence of H. pylori 3401. This study may lead to the establishment of phage therapy against H. pylori infection.

Cytotoxin-associated gene A (CagA) promotes aortic endothelial inflammation and accelerates atherosclerosis through the NLRP3/caspase-1/IL-1β axis.

Atherosclerosis is a chronic inflammatory disease. Pathophysiological similarities between chronic infections and atherosclerosis triggered interests between these conditions. The seroepidemiological study showed that Helicobacter pylori strains that express cytotoxin-associated gene A (CagA), an oncoprotein and a major virulence factor, was positively correlated with atherosclerosis and related clinical events. Nevertheless, the underlying mechanism is poorly understood. In this study, the seroprevalence of infection by H. pylori and by strains express CagA assessed by enzyme-linked immunosorbent assay (ELISA) showed that the prevalence of CagA strains rather than H. pylori in patients was positively correlated with atherogenesis. Correspondingly, we found that CagA augmented the growth of plaque of ApoE-/- mice in the early stage of atherosclerosis and promoted the expression of adhesion molecules and inflammatory cytokines in mouse aortic endothelial cells (MAECs). Mechanistically, both si-NLRP3 and si-IL-1β mitigated the promoting effect of CagA on the inflammatory activation of HAECs. In vivo, the inhibition of NLRP3 by MCC950 significantly attenuated the promoting effect of CagA on plaque growth of ApoE-/- mice. We also propose NLRP3 as a potential therapeutic target for CagA-positive H. pylori infection-related atherosclerosis and emphasize the importance of inflammation in atherosclerosis pathology.

Effect of some medicinal plant extracts on multidrug resistant Helicobacter pylori strains isolated from Sohag and Assiut University Hospitals and some medical laboratories

Effect of some medicinal plant extracts on multidrug resistant Helicobacter pylori strains isolated from Sohag and Assiut University Hospitals and some medical laboratories

Effect of some medicinal plant extracts on multidrug resistant Helicobacter pylori strains isolated from Sohag and Assiut University Hospitals and some medical laboratories

Effect of some medicinal plant extracts on multidrug resistant Helicobacter pylori strains isolated from Sohag and Assiut University Hospitals and some medical laboratories

A comprehensive method for determining cellular uptake of purine nucleoside phosphorylase and adenylosuccinate synthetase inhibitors by H. pylori

Due to the growing number of Helicobacter pylori strains resistant to currently available antibiotics, there is an urgent need to design new drugs utilizing different molecular mechanisms than those that have been used up to now. Enzymes of the purine salvage pathway are possible targets of such new antibiotics because H. pylori is not able to synthetize purine nucleotides de novo. The bacterium’s recovery of purines and purine nucleotides from the environment is the only source of these essential DNA and RNA building blocks. We have identified formycins and hadacidin as potent inhibitors of purine nucleoside phosphorylase (PNP) and adenylosuccinate synthetase (AdSS) from H. pylori — two key enzymes of the purine salvage pathway. However, we have found that these compounds are not effective in H. pylori cell cultures. To address this issue, we have developed a universal comprehensive method for assessing H. pylori cell penetration by drug candidates, with three alternative detection assays. These include liquid chromatography tandem mass spectrometry, UV absorption, and inhibition of the target enzyme by the tested compound. Using this approach, we have shown that cellular uptake by H. pylori of formycins and hadacidin is very poor, which reveals why their in vitro inhibition of PNP and AdSS and their effect on H. pylori cell cultures are so different. The cell penetration assessment method developed here will be extremely useful for validating the cellular uptake of other drug candidates, facilitating the design of new potent therapeutic agents against H. pylori.Key points• A method for assessing H. pylori cells penetration by drug candidates is described.• Three alternative detection assays that complement each other can be used.• The method may be adapted for other bacteria as well.

Helicobacter Pylori Induce Gastric Upset

Editorial: Helicobacter pylori is a micro-aerophilic, helical-form gramnegative aggressive bacteria. Accordingly, the idiom “Helico” intimates its helical appearance, “bacter” symbolizes bacteria, while “pylori” denotes stomach due to the first and common site of this bacteria living. Further, Marshall B. and Warren R. observed and described it in 1982. Then, the followed investigators studied this bacterium in detail with its consequences and complexities [1]. Gastric upset (Indigestion), dyspepsia: means impaired gastric digestion. Accordingly, the patient complains of upper abdominal pain, heartburn, belching, nausea, even feeling earlier gastric fullness than expected while eating. Furthermore, there are many causes of indigestion like gastroesophageal reflux disease, ulcer disease, gastritis, and even gastric cancer. Hence, unexplained recent onset dyspepsia in older people may need additional examinations. Moreover, one of the common causes is Helicobacter pylori infection, which needs laboratory and endoscopic examination [2]. Argument Many theories investigated the etiology and pathogenesis of Helicobacter pylori infection, concerning chronic or acute gastritis. Hence, gastric upset is the main presentation of both types of gastritis. Evidences The genotype is valuable in determining the dominant Helicobacter pylori strains as the isolates were different genetically plus heterogeneous distribution. Accordingly, the vac and cag markers operate a significant function in defining clinical consequences. These virulence agents are present in a subset of Helicobacter pylori strains isolates like cagA, iceA, vacA, and ureC. Moreover, the cagA causes cytotoxins induction by the gastric epithelial cell as Interleukin 8 [3]. The molecular intercommunication researches exhibit that the act of acarus calamus in hindering biofilm formation in Helicobacter pylori is due to the inhibitory impact of phytobio-active component, β-sitosterol, on the quorum sensing molecules-ToxB, PhnB, DnaA, plus Sip. Consequently, this opinion may suggest the molecular mechanism of Helicobacter pylori in producing the acidrelated complaints and gives a clue to a new therapy [4]. Helicobacter pylori infection causes lncRNA risk impression linked to H. pylori in gastric cancer patients and can prognosticate the prediction of these patients [5]. There was a close relationship between raised serum IgE levels in Helicobacter pylori infected patients [6]. Counterargument The laboratory investigations of Helicobacter pylori infection depend on several factors like the fluctuations of serum antibody titers in a time series, the antigene detection in stool tests, the false-positive results of lab tests, or the manner of endoscopic biopsy collection. Furthermore, other factors like the variations in Cytotoxin-Associated Gene A (CagA) in East Asian patients. Moreover, the gastric nodularity or atrophy, the patient’s age, the severity of the gastric mucosal infection are causes of variations in Helicobacter pylori detection at the time of the investigation [7]. Refutation The significant markers of H. pylori, the presence of the vacuolating cytotoxin (vacA), the cytotoxin-associated gene A (cagA), which induced by the direct communication with gastric epithelium factor antigen (iceA gene), and the presence of urease C gene (ureC). Consequently, all these factors play the principal factors in deciding the gastric consequences of Helicobacter infections. Conclusion Helicobacter pylori induce gastric upset by several mechanisms to form numerous Gastric diseases.

Biliary Migration, Colonization, and Pathogenesis of O. viverrini Co-Infected with CagA+ Helicobacter pylori.

Co-infection with the cagA strain of Helicobacter pylori exacerbates the pathology of human liver fluke Opisthorchis viverrini (OV) infection leading to cholangiocarcinoma. However, underlying mechanisms remain unclear. We report a significant increase in cagA-positive and cagA-negative H. pylori in the stomach, blood, bile, and in the OV worms of co-infected Syrian golden hamsters at one hour, three hours, and one month, post-infection, compared to hamsters infected with either OV or H. pylori alone. Except in the worms, H. pylori numbers declined at three months post-infection, particularly in the bile fluid of co-infected animals. Both strains of H. pylori were immunohistochemically detected in the tegument of the worm, as well as in the bile duct epithelium when co-infected with O. viverrine, but not in H. pylori infection alone. Interestingly, only the cagA-positive strain was detected in the gut of the worm. Co-infection between cagA-positive H. pylori and O. viverrini resulted in a more severe biliary pathology and decreased E-cadherin expression in vivo and in vitro than those of the cagA-negative strain. These data suggest that O. viverrini acts as a carrier of cagA-positive H. pylori and co-migrates to the bile ducts, whereas O. viverrini facilitates H. pylori colonization and enhances the biliary pathogenesis and carcinogenesis.

Evaluating the relationship between Helicobacter pylori infection and carotid intima-media thickness a cross sectional study

IntroductionHelicobacter pylori is a gram-negative spiral bacterium that is frequently found in the human stomach. Significant association has been reported between Cytotoxin associated gene A (CagA)- positive Helicobacter pylori strains and coronary heart disease. The aim of the present study is to investigate the carotid intima-media thickness as an indicator of atherosclerosis in people with Helicobacter pylori infection. MethodsThis study was done on patients who underwent upper GI endoscopy and biopsy, and after obtaining conscious consent underwent ultrasound of the right and left carotid arteries for measuring carotid intima-media thickness (CIMT) and blood tests. ResultsIn this study, 90 patients who underwent upper GI endoscopy were examined in three groups: negative H. pylori negative, positive cagA and negative cagA. The right, left and average of CIMT in cagA-positive group were significantly higher than the other two groups (p < 0.05). Howerver, the average of CIMT was not significantly different between men and women. Also, the hsCRP average level in positive cagA group was significantly higher than other groups (p < 0.05). ConclusionOur findings suggest that there is an increase in CIMT values in patients with H. pylori infection, especially in cases of positive cagA. The positive cagA group showed significantly higher levels of hs-CRP, as a marker of elevated inflammatory response. Therefore, H. pylori infection, especially cagA-positive strains and its associated systemic inflammatory response can be considered as a contributing factor in atherosclerosis and cardiovascular disease.

In Vitro Screening Potential Antibacterial Properties of the Greek Oregano Honey against Clinical Isolates of Helicobacter pylori.

Oregano honey is an exceedingly rare and distinct product, not commercially available, produced by bees bred in oregano fields of alpine altitudes at the mountainous area of Epirus, Greece. In ethnic popular medicine, this product is used as a therapeutic in various gastric diseases. To test this hypothesis, 14 strains of Helicobacter pylori (H. pylori), 6 isolated from gastric ulcers and 8 from cases of clinical gastritis, were employed in the present study. The above bacterial strains were exposed to various concentrations (75% v/v, 50% v/v, 25% v/v, 12.5% v/v, and 6% v/v) of 50 oregano honey samples by using the agar well method and the inhibition zones observed around each well were recorded. Although the inhibitory zones of the H. pylori isolated from the gastric ulcers were wide enough (0–34 mm), those strains, in general, appeared more resistant than the other eight (0–58 mm). The same result was observed when the same strains were tested against six antibiotics used in clinical practice. Extracts of oregano honey were prepared by extraction with four different organic solvents. N-hexane and chloroform extracts had the most potent antibacterial action. Finally, pure oregano honey and diethyl ether extracts of honey showed significant inhibitory activity against urease secreted by the pathogen. These results strongly indicate the susceptibility of H. pylori strains to the oregano honey by more than one mode of action. Consequently, this variety of honey seems to have potential therapeutic properties against gastric ulcers and gastritis, thus explaining the preference of the locals towards this traditional remedy.

Geographic distribution of the cagA, vacA, iceA, oipA and dupA genes of Helicobacter pylori strains isolated in China

BackgroundThere are geographic variations in the genotypes of Helicobacter pylori (H. pylori) cagA, vacA, iceA, oipA and dupA. The aim of the study was to investigate the distribution of these genotypes among H. pylori strains from five regions of China and their association with clinical outcomes.Materials and methodsGastric biopsy specimens were obtained from 348 patients with different gastrointestinal diseases in the five regions of China. The regional distribution was 89 patients from Shandong, 91 from Guangxi, 57 from Hunan, 58 from Qinghai and 53 from Heilongjiang. The presence of cagA, vacA, iceA, oipA and dupA genotypes was determined by polymerase chain reaction (PCR) from H. pylori DNA.ResultsA total of 269 H. pylori isolates were obtained, of which 74 isolates were from Shandong, 78 from Guangxi, 46 from Hunan, 33 from Qinghai and 38 from Heilongjiang. The cagA-positive status was predominant in the five regions. The predominant vacA genotypes were s1c (73.4%), m2 (70.6%) and i1 (92.9%). In strains from Shandong, s1a and m1 were dominant. By contrast, s1c was dominant in Guangxi and i1 was dominant in Hunan and Heilongjiang. The prevalence of m2 subtype in Qinghai (78.8%) was significantly higher than that in other regions (P < 0.05). The predominant iceA genotype was iceA1 and the frequency of iceA1 was significantly more prevalent in Hunan than in other regions (P < 0.05). The oipA status “on” gene was more frequent in Shandong (91.9%) and Guangxi (91%) than in Heilongjiang (71.7%) (P < 0.05). Conversely, the dupA-positive status was less than half in Shandong (31.1%) and Guangxi (15.4%), whereas it was 73.9% in Hunan and 81.8% in Qinghai (P < 0.001). There were no significant associations between the cagA, vacA, iceA, oipA genotypes and clinical outcomes. The dupA-positive strains were more common in peptic ulcer disease (PUD) patients than in non-ulcer dyspepsia (NUD) patients in Shandong and Guangxi (P < 0.05), but the association was not observed in other geographic regions.ConclusionsThere was significant geographic diversity of H. pylori genotypes in different regions of China and the presence of dupA gene can be considered as a marker for the development of gastroduodenal diseases. However, the cagA, iceA, vacA and oipA genes cannot be regarded for prediction of the clinical presentation of H. pylori infection in China.

Isolation of dupA-positive and clarithromycin-resistant Helicobacter pylori from Iranian patients with duodenal ulcer

BackgroundEmergence of the antibiotic-resistant Helicobacter pylori strains has compelled the development of novel and complex therapeutic approaches. The duodenal-ulcer-promoting gene A (dupA), a virulence factor of H. pylori, is thought to be associated with a high risk of duodenal ulcerations but not gastric cancer. We propose that the association between clarithromycin resistance and presence of dupA may help clinicians formulate better therapeutic regimens. MethodsWe thus investigated H. pylori colonization in 90 patients, including 27 with gastritis, 40 with duodenal ulcer, and 23 with gastric cancer. We used the E-test for determining the minimal inhibitory concentrations of clarithromycin according to standard protocols. Bacterial culturing and glmM-specific PCR were used to determine the prevalence of the relevant H. pylori strains. ResultsdupA-Positive strains were not equally distributed among the three disease groups (gastritis 32.5%; duodenal ulcer 62.9%; gastric cancer 21.7%). We found a significant association between dupA-positive H. pylori strains and duodenal ulcer (P = 0.02; OR: 2.67; 0.95 CI: 1.09–6.49). We assessed the susceptibility to clarithromycin of the H. pylori isolates. Clarithromycin resistance was prevalent in 47% of the isolates. The dupA-positive H. pylori strains were more resistant to clarithromycin (P = 0.013; OR: 3.12; 0.95 CI: 1.20–8.11) than other strains. ConclusionWe conclude that dupA presence may be a marker for clarithromycin-resistant H. pylori strains among the patients with duodenal ulcer.

Draft Genome Sequences of 29 Helicobacter pylori Strains Isolated from Colombia.

Here, we present the draft genome sequences of 29 Colombian Helicobacter pylori strains. These strains were isolated in Bogotá, Colombia, from patients diagnosed with chronic gastritis. The genomic characterization of these strains will provide more information on the genetic composition of H. pylori strains from Colombia.

Geographical diversity of Helicobacter pylori strains circulating in the European Part of the Russian Federation

The aim of the study was to identify INDEL markers and study geographical origin of regional H. pylori strains circulating in the European part of the Russian Federation. The study included 56 strains of H. pylori isolated in three regions of the Russian Federation: Saint Petersburg, Astrakhan and Rostov Regions. Genomic DNA was isolated using a set of Probe NA (DNA Technology, Russia), according to the manufacturer’s instructions. Detection of INDEL markers hp5605, hp6405, hp340, hp1390, hp3660 was performed using PCR. Clustering of the identified INDEL genotypes and building a phylogenetic tree were performed using the BioNumerics 7.6 and GrapeTree software packages. 21 strains from the GenBank database with known geographical origin were used as reference strains. In 20 strains from Saint Petersburg, 13 individual genotypes were identified, while 17 strains belong to the European cluster (hpEurope), 2 strains belong to the hspEAsia cluster and one strain belongs to the hspWAfrica cluster. The most common genotype identified in the European cluster includes six strains from Saint Petersburg and two strains from the GenBank database. For further differentiation of these strains, the VNTR typing method was used, which allowed identifying eight individual genotypes in eight strains. Fifty-six studied russian strains are represented by thirty individual genotypes, which reflects the high heterogeneity of strains circulating in the European part of the Russian Federation. The most frequent genotype is represented by two hpEurope strains, one strain from the Astrakhan region, as well as 5 and 6 strains from the Rostov Region and Saint Petersburg, respectively. The vast majority of Russian strains (52/56) belong to the hpEurope population, while two strains from Saint Petersburg are included in the hspEAsia population, and one strain from Saint Petersburg and the Astrakhan Region is included in the hspWAfrica population. Total, 77 H. pylori strains are represented by 37 individual genotypes with a high diversity index (DI = 0.95), which allows us to consider the proposed INDEL typing method as an independent method for genotyping H. pylori strains. Taking into consideration the complexity of the problem of accurately determining the geographical origin of H. pylori strains, the proposed simple and convenient method of INDEL typing of H. pylori strains, based on an available PCR method becomes very relevant and allows us to conduct an adequate primary analysis of the geographical origin of Russian H. pylori strains.

Clinical Strains of Helicobacter pylori With Strong Cell Invasiveness and the Protective Effect of Patchouli Alcohol by Improving miR-30b/C Mediated Xenophagy.

Helicobacter pylori was classified by the World Health Organization as a class 1 carcinogen. The development of drug-resistant strains of this pathogen poses a serious threat to human health worldwide. The cell invasion of H. pylori activates xenophagy in gastric epithelial cells by mediating miR-30b/c, and the emergence of autophagosomes provides a niche that enables the survival of intracellular H. pylori and promotes its drug resistance. This study revealed that some clinical drug-resistant H. pylori strains present much stronger invasive ability than standard strains. Patchouli alcohol (PA), a tricyclic sesquiterpene from Pogostemon cablin (Blanco) Benth (Labiatae), showed reliable activity against intracellular H. pylori. The mechanisms appeared to involve the downregulation of miR-30c-3p/5p and miR-30b-5p, thereby upregulating xenophagy-related gene expression (ULK1, ATG5, ATG12, and ATG14) and enhancing xenophagy. PA also inhibited the nuclear transfection of miR-30b-5p induced by H. pylori, thereby enhancing transcription factor EB function and increasing lysosome activity. The finding of strongly invasive intracellular H. pylori has great implications for clinical treatment, and PA can act against invasive H. pylori based on the improvement of miR-30b/c mediated xenophagy. Taken together, the results demonstrate that PA have potential use as a candidate medication for intracellular drug-resistant H. pylori.

Role of genetic structure of Helicobacter Pylori in formation of chronic inflammatory process in gastric mucosa

The literature review highlights the questions of the interaction of Helicobacter pylori and the human body. Modern data on the structure of the pathogenicity island in the Helicobacter pylori genome are presented. There is given a detailed description of both well-known virulence and pathogenicity factors of the infection (genes encoding the formation of urease subunits, in particular urel, cytotoxin associated gene A, vacuolating cytotoxin gen A, blood group associated binding adhesion, induced by contact with epithelium) and less studied ones (sialic acid-binding adhesion, adhesion-associated lipoprotein A and B, adhesin gene of Helicobacter pylori, Hp outer membrane protein). The significance of individual genes and proteins encoded by them in the development of chronic inflammatory process in diseases of the upper digestive tract, as well as in ulcer and carcinogenesis is analyzed. Mechanisms of interaction of bacteria with epithelial cells of the gastric mucosa, adhesive and cytotoxic effects of Helicobacter pylori, factors of biofilm formation are described. The influence of the genetic structure of Infect on cytological composition of the gastric glands in the form of reduction of specialized glandular cells chief and parietal cells of pyloric glands and the increase of endocrine cells in the pool is assessed. It is shown that colonization of the gastric mucosa by highly pathogenic strains of Helicobacter pylori contributes to the development of widespread pronounced and active inflammation in it, the appearance of morphological signs of atrophy. The role of the genetic characteristics of the infection in the failure of anti-helicobacter therapy is emphasized. Separately, the question of the effect of combined infection of the gastric mucosa with highly pathogenic strains of Helicobacter pylori and Epstein-Barr virus is highlighted.

Diversity of 3\u2032 variable region of cagA gene in Helicobacter pylori strains isolated from Chinese population

BackgroundThe cytotoxin-associated gene A (cagA) is one of the most important virulence factors of Helicobacter pylori (H. pylori). There is a highly polymorphic Glu-Pro-Ile-Tyr-Ala (EPIYA) repeat region in the C-terminal of CagA protein. This repeat region is thought to play an important role in the pathogenesis of gastrointestinal diseases. The aim of this study was to investigate the diversity of cagA 3′ variable region and the amino acid polymorphisms in the EPIYA segments of the CagA C-terminal region of H. pylori, and their association with gastroduodenal diseases.MethodsA total of 515 H. pylori strains from patients in 14 different geographical regions of China were collected. The genomic DNA from each strain was extracted and the cagA 3′ variable region was amplified by polymerase chain reaction (PCR). The PCR products were sequenced and analyzed using MEGA 7.0 software.ResultsA total of 503 (97.7%) H. pylori strains were cagA-positive and 1,587 EPIYA motifs were identified, including 12 types of EPIYA or EPIYA-like sequences. In addition to the four reported major segments, several rare segments (e.g., B′, B″ and D′) were defined and 20 different sequence types (e.g., ABD, ABC) were found in our study. A total of 481 (95.6%) strains carried the East Asian type CagA, and the ABD subtypes were most prevalent (82.1%). Only 22 strains carried the Western type CagA, which included AC, ABC, ABCC and ABCCCC subtypes. The CagA-ABD subtype had statistical difference in different geographical regions (P = 0.006). There were seven amino acid polymorphisms in the sequences surrounding the EPIYA motifs, among which amino acids 893 and 894 had a statistical difference with gastric cancer (P = 0.004).ConclusionsIn this study, 503 CagA sequences were studied and analyzed in depth. In Chinese population, most H. pylori strains were of the CagA-ABD subtype and its presence was associated with gastroduodenal diseases. Amino acid polymorphisms at residues 893 and 894 flanking the EPIYA motifs had a statistically significant association with gastric cancer.

Helicobacter pylori resistance to antibiotics in Europe in 2018 and its relationship to antibiotic consumption in the community

ObjectiveOur aim was to prospectively assess the antibiotic resistance rates in Helicobacter pylori strains in Europe in 2018 and to study the link between antibiotic consumption in the community and...

Whole-Genome Sequencing and Comparative Genomics of Three Helicobacter pylori Strains Isolated from the Stomach of a Patient with Adenocarcinoma.

Helicobacter pylori is a common pathogen associated with several severe digestive diseases. Although multiple virulence factors have been described, it is still unclear the role of virulence factors on H. pylori pathogenesis and disease progression. Whole genome sequencing could help to find genetic markers of virulence strains. In this work, we analyzed three complete genomes from isolates obtained at the same point in time from a stomach of a patient with adenocarcinoma, using multiple available bioinformatics tools. The genome analysis of the strains B508A-S1, B508A-T2A and B508A-T4 revealed that they were cagA, babA and sabB/hopO negative. The differences among the three genomes were mainly related to outer membrane proteins, methylases, restriction modification systems and flagellar biosynthesis proteins. The strain B508A-T2A was the only one presenting the genotype vacA s1, and had the most distinct genome as it exhibited fewer shared genes, higher number of unique genes, and more polymorphisms were found in this genome. With all the accumulated information, no significant differences were found among the isolates regarding virulence and origin of the isolates. Nevertheless, some B508A-T2A genome characteristics could be linked to the pathogenicity of H. pylori.