scholarly journals Helicobacter Pylori Variants with ABC-Type Tyrosine Phosphorylation Motif in Gastric Biopsies of Ghanaian Patients

2021 ◽  
Vol 2021 ◽  
pp. 1-7
Author(s):  
Emmanuel A. Tagoe ◽  
Gordon A. Awandare ◽  
Osbourne Quaye ◽  
Richard H. Asmah ◽  
Timothy N. Archampong ◽  
...  
Keyword(s):  
Amino Acids ◽  
Helicobacter Pylori ◽  
Amino Acid ◽  
Tyrosine Phosphorylation ◽  
Gastric Disease ◽  
Rrna Gene ◽  
Caga Gene ◽  
Caga Protein ◽  
Gastric Biopsies ◽  
H Pylori

Background. Helicobacter pylori pathogenicity and disease severity are determined by the tyrosine phosphorylation motifs of CagA protein. This study is aimed at detecting the presence of H. pylori and identifying the CagA tyrosine phosphorylation motifs in Ghanaian patients. Material and Methods. A total of 94 archival genomic DNA samples from gastric biopsies were used for the study, and H. pylori was detected by amplifying the 16S rRNA gene. The 3 ′ -end variable region of the cagA gene was amplified, and the entire 3 ′ -end was sequenced and translated into amino acids. Results. H. pylori was detected in 53.2% (50/94) of the samples, and all the detected bacteria harboured the cagA gene. Two variants of the bacteria were identified based on the size of the amplified cagA gene: 207 bp and 285 bp. The 207 bp and 285 bp variants accounted for 74% and 22%, respectively, and 4% showed both fragments. Translated amino acid sequence of the cagA gene showed EPIYA-A, EPIYA-B, and EPIYA-C (ABC type) motifs, indicating the Western variant. The CagA protein C-terminal showed insertion of amino acids in the sequence flanking the EPIYA-A motif at the N-terminal and a complete deletion of the EPIYA-CC and EPIYA-CCC motifs together with the flanking sequences. Conclusions. H. pylori identified were Western variant (ABC type) with unique amino acid insertions, suggesting unique variants in Ghanaian patients. Further investigation is however required to understand the role of the molecular diversity of the variant in gastric disease outcome.

Frequency of rdx A Deletion Mutation Conferring Metronidazole Resistance in Helicobacter pylori

2020 ◽  
Vol 29 (3) ◽  
pp. 59-64
Author(s):  
Hanaa M. El Maghraby ◽  
Samar Mohaseb
Keyword(s):  
Helicobacter Pylori ◽  
Epigastric Pain ◽  
Deletion Mutation ◽  
Rapid Urease Test ◽  
Rrna Gene ◽  
University Hospitals ◽  
Metronidazole Resistance ◽  
Urease Test ◽  
Gastric Biopsies ◽  
H Pylori

Background: Metronidazole is one of the antimicrobial drugs that can be used in combination with other drugs for eradication of Helicobacter pylori (H. pylori).Unfortunately, metronidazole resistance in H. plori is an increasing health problem which may be attributed to inactivation of many genes as rdx A gene. Objective: To determine the frequency of rdx A deletion mutation in H. pylori detected in infected patients attending at the Gastroenterology Unit, Zagazig University Hospitals. Methodology: Two gastric biopsies were taken from each enrolled patient by endoscopy. H.pylori detection was done by rapid urease test and polymerase chain reaction (PCR) amplification of 16S rRNA gene. Deletion mutation in rdx A gene was detected by conventional PCR. Results: Out of 134 doubled gastric biopsies obtained from 134 patients, 52.2% were positive for H. pylori. Epigastric pain, vomiting and gastritis were significantly associated with detection of H. pylori infection (p˂ 0.05). Deletion mutation of rdx A gene was detected in 28.6% of H. pylori positive specimens obtained from infected patients. Conclusion: Deletion mutation of rdx A gene is a frequent determinant of rdx A inactivation conferring metronidazole resistance among H. pylori.

scholarly journals Dissemination of cagA and cagE Virulence Genes Among H. Pylori Strains From Sudanese Patients With Gastric Discomfort

2021 ◽  
Author(s):  
Esraa Osman ◽  
Maram M. Elnosh ◽  
Aalaa Mahgoub Albasha ◽  
Amira A M Fadl ◽  
Luai Osman Ibrahim Marouf ◽  
...  
Keyword(s):  
Duodenal Ulcer ◽  
Helicobacter Pylori ◽  
Gastric Ulcer ◽  
Amino Acid ◽  
Virulence Genes ◽  
Protein Sequences ◽  
Pathogenicity Island ◽  
E Gene ◽  
Gastric Biopsies ◽  
H Pylori

Abstract ObjectivesHelicobacter pylori cytotoxin-associated gene pathogenicity island (cag-PAI) is one of the strain-specific genes (they do not exist in all strains). cag-PAI is involved in inducing inflammation, ulceration, and carcinogenesis. This study aimed to detect and characterize cagA and cagE virulence genes among H. pylori strains from Sudanese patients with gastric discomfort.ResultOut of 288 gastric biopsies screened for the presence of H. pylori, 34% (98/288) were positive, cagA gene was present in 41% (40/98) of specimens, mostly in patients with gastritis 72.5% (29/40), followed by duodenal ulcer 15% (6/40), esophagitis 5% (2/40), and 7.5% (3/40) in patients diagnosed normal by endoscopy. cagE gene was present in 39% (38/98) of specimens, the majority 73.7% (28/38) were from patients with gastritis, 10.5% (4/38) duodenal ulcer, 5.3% (2/38) esophagitis, 2.6% (1/38) gastric ulcer, and 7.9% (3/38) were diagnosed as normal. The cagA and cagE protein sequences have synonymous amino acid variations.

scholarly journals Coupled Amino Acid Deamidase-Transport Systems Essential for Helicobacter pylori Colonization

2010 ◽  
Vol 78 (6) ◽  
pp. 2782-2792 ◽  
Author(s):  
Damien Leduc ◽  
Julien Gallaud ◽  
Kerstin Stingl ◽  
Hilde de Reuse
Keyword(s):  
Amino Acids ◽  
Helicobacter Pylori ◽  
Amino Acid ◽  
Nitrogen Sources ◽  
Host Cells ◽  
Transport Systems ◽  
Uptake System ◽  
Highly Active ◽  
H Pylori

ABSTRACT In addition to their classical roles as carbon or nitrogen sources, amino acids can be used for bacterial virulence, colonization, or stress resistance. We found that original deamidase-transport systems impact colonization by Helicobacter pylori, a human pathogen associated with gastric pathologies, including adenocarcinoma. We demonstrated that l-asparaginase (Hp-AnsB) and γ-glutamyltranspeptidase (Hp-γGT) are highly active periplasmic deamidases in H. pylori, producing ammonia and aspartate or glutamate from asparagine and glutamine, respectively. Hp-GltS was identified as a sole and specialized transporter for glutamate, while aspartate was exclusively imported by Hp-DcuA. Uptake of Gln and Asn strictly relies on indirect pathways following prior periplasmic deamidation into Glu and Asp. Hence, in H. pylori, the coupled action of periplasmic deamidases with their respective transporters enables the acquisition of Glu and Asp from Gln and Asn, respectively. These systems were active at neutral rather than acidic pH, suggesting their function near the host epithelial cells. We showed that Hp-DcuA, the fourth component of these novel deamidase-transport systems, was as crucial as Hp-γGT, Hp-AnsB, and Hp-GltS for animal model colonization. In conclusion, the pH-regulated coupled amino acid deamidase-uptake system represents an original optimized system that is essential for in vivo colonization of the stomach environment by H. pylori. We propose a model in which these two nonredundant systems participate in H. pylori virulence by depleting gastric or immune cells from protective amino acids such as Gln and producing toxic ammonia close to the host cells.

Increased Production of Matrix Metalloproteinases in Helicobacter pylori Infection that Stimulates Gastric Cancer Stem Cells

2020 ◽  
Keyword(s):  
Gastric Cancer ◽  
Stem Cells ◽  
Helicobacter Pylori ◽  
Cancer Stem Cells ◽  
Histopathological Examination ◽  
Physiological Saline ◽  
Rrna Gene ◽  
Peptic Ulcers ◽  
Gastric Cancer Stem Cells ◽  
H Pylori

Background and aim: Helicobacter pylori (H. pylori) is an incriminated pathogen causing diseases in both animals and humans and considered a zoonotic pathogen. H. pylori infection is considered a cause of gastric cancer, which rests a significant health care challenge. This study analyzes the expression pattern of matrix metalloprotein 2 (MMP-2) in patients with Helicobacter pylori-associated gastritis and the effect of H. pylori on gastric cancer stem cells, as well as study the role of helicon bacteriosis in dog in transmission of H. pylori infection to human. Materials and methods: Fifty-five of each sample (gastric biopsy, blood and stool) were collected from patients suffering from dyspepsia, chronic vomiting and perforated peptic ulcers and also from apparent healthy dogs. The investigation detected H. pylori by serological and histopathological examination. Biopsies were stored in physiological saline for identification of H. pylori by conventional time PCR. MMP-2 and Gastric cancer stem cells were then identified by immunohistochemistry. Results: Serological identification for H. pylori Antigen and Antibodies revealed (63% human, 50% dogs) and (87% human, 90% dogs) respectively were positive. Genotyping of H. pylori based on 16S rRNA gene showed 54.5% of human and 35% of dogs were positive. Immunohistochemistry revealed strong expression of CD44 in H. pylori- associated gastric cancer cases, MMP-2 expression was observed in all neoplastic lesions associated with H. pylori infection. Conclusion: H. pylori infection affects gastric mucosa and induces changes in gastric stem cells altering their differentiation and increased expression of MMP’s and CD44with a resultant potentiation of oncogenic alteration. In addition the up-regulation of both markers could be an instrumental to interpret the origination of gastric cancer.

Analysis of babA, cagE and cagA Genes in Helicobacter pylori from Upper Gastric Patients in the North of Iran

2019 ◽  
Vol 19 (3) ◽  
pp. 274-278 ◽  
Author(s):  
Saba Fakhrieh Asl ◽  
Mehrnaz Pourvahedi ◽  
Ali Mojtahedi ◽  
Mohammad Shenagari
Keyword(s):  
Helicobacter Pylori ◽  
Gastric Diseases ◽  
Specific Primers ◽  
The North ◽  
Different Types ◽  
North Of Iran ◽  
Gastric Biopsies ◽  
Pcr Method ◽  
Non Ulcer Dyspepsia ◽  
H Pylori

Objective:Helicobacter pylori is a Gram-negative bacterium which has a serious effect on up to half of the world’s population and has been related to different gastric diseases. The goal of this study was to assess the frequency of babA, cagE and cagA genotypes among H. pylori strains isolated from gastric biopsies of endoscopic patients in the north of Iran.Methods:The present study was performed on 90 strains of H. pylori isolated from patients with gastric diseases (Gastric ulcer (GU), Duodenal ulcer (DU), Gastritis (G), Non-ulcer dyspepsia (NUD) and Gastric adenocarcinoma (GC)). DNA was extracted from all isolated strains and PCR method was performed to detect the prevalence of babA2, cagE and cagA genes using specific primers.Results:Among 90 samples of H. pylori, babA2, cagE, and cagA genes were detected in 42.2%, 30% and 82.2% of strains respectively. The statistical analysis showed that the prevalence of cagA gene in GU, G, DU, and NUD was significantly higher than other genes. Moreover, cagA, and babA2 genes were significantly more prevalent in GC patients compared to cagE gene. Our isolates exhibited 8 distinct arrangements of virulence patterns. The occurrence of cagA (35.6%) was the most prevalent pattern followed by cagA/babA2 (20%) and cagA/babA2/cagE (14.4%).Conclusion:In summary, as first report from Guilan province in the north of Iran, we showed significant association between the presence of babA2, cagE, and cagA genes in different types of gastric disorders.

scholarly journals Diversity of 3′ variable region of cagA gene in Helicobacter pylori strains isolated from Chinese population

Gut Pathogens ◽  
2021 ◽  
Vol 13 (1) ◽  
Author(s):  
Zhijing Xue ◽  
Yuanhai You ◽  
Lihua He ◽  
Yanan Gong ◽  
Lu Sun ◽  
...  
Keyword(s):  
Gastric Cancer ◽  
Helicobacter Pylori ◽  
Amino Acid ◽  
Chinese Population ◽  
Statistical Difference ◽  
Variable Region ◽  
Repeat Region ◽  
Geographical Regions ◽  
H Pylori ◽  
Epiya Motifs

Abstract Background The 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. Methods A 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. Results A 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). Conclusions In 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.

scholarly journals Genotyping pattern of the vacuolating cytotoxin A and cytotoxin associated gene A of the Helicobacter pylori strains detected in fecal samples of household dogs

2017 ◽  
Vol 8 (2) ◽  
Author(s):  
Asieh Bolandi ◽  
Saam Torkan ◽  
Iman Alavi
Keyword(s):  
Helicobacter Pylori ◽  
16S Rrna ◽  
16S Rrna Gene ◽  
Pcr Amplification ◽  
Rrna Gene ◽  
Fecal Samples ◽  
The Status ◽  
Cytotoxin Associated Gene A ◽  
H Pylori

In despite of the high clinical impact of Helicobacter pylori, its exact sources and routes of transmission are unknown. Dogs may play an imperative role in the transmission of H. pylori to humans. The current investigation was done to study the status of vacA and cagA genotypes in the H. pylori strains of dogs. One-hundred and fifty fecal samples were collected from healthy and complicated household dogs. Genomic DNA was extracted from fecal samples and presence of 16S rRNA gene was studied using the PCR amplification. Distribution of vacA and cagA genotypes were studied by the multiplex PCR. Thirteen out of 150 fecal samples (8.66%) were positive for H. pylori 16S rRNA gene. Prevalence of H. pylori in healthy and complicated dogs were 5.55% and 8.57%, respectively. Male had the higher prevalence of H. pylori (P=0.038). The most commonly detected genotypes among the H. pylori strains were vacAs1A (61.53%), cagA (38.46%), vacAm1a (38.46%), vacAs2 (30.76%) and vacAm2 (30.76%). The most commonly detected combined genotypes were s1aCagA (30.76%), s1am1a (23.07%), s2m1a (23.07%) and s2CagA (23.07%). Iranian household dogs harbor H. pylori in their fecal samples similar in genotypes of the vacA and cagA alleles which suggest that complicated and even healthy dogs may be the latent host of the H. pylori and its genotypes. However, supplementary studies are required to found the exact role of dogs as a definitive host of the H. pylori.

scholarly journals Genetic Diversity of the cagA gene of Helicobacter pylori strains from Sudanese Patients with Different Gastroduodenal Diseases

2019 ◽  
Author(s):  
Hadeel Gassim Hassan ◽  
Abeer Babiker Idris ◽  
Mohamed A. Hassan ◽  
Hisham N. Altayb ◽  
Kyakonye Yasin ◽  
...  
Keyword(s):  
Helicobacter Pylori ◽  
Amino Acid ◽  
Novel Mutation ◽  
Amino Acid Residues ◽  
Specific Amino Acid ◽  
Gastrointestinal Malignancy ◽  
High Incidence ◽  
H Pylori ◽  
High Level ◽  
Chloride Method

AbstractBackgroundThere is an increase in the prevalence of Helicobacter pylori infection in Sudan, accompanied by a high incidence of upper gastrointestinal malignancy. The cytotoxin-associated gene cagA gene is a marker of a pathogenicity island (PAI) in H. pylori and plays a crucial role in determining the clinical outcome of Helicobacter infections.ObjectiveThis study aimed to determine the frequency and heterogeneity of the cagA gene of H. pylori and correlate the presence of cagA gene with clinical outcomes.Materials and methodsFifty endoscopy biopsies were collected from Fedail and Soba hospitals in Khartoum state. DNA was extracted using the Guanidine chloride method followed by PCR to amplify 16S rRNA and cagA gene of H. pylori using specific primers. DNA amplicons of cagA gene were purified and sequenced. Bioinformatics and statistical analysis were done to characterize and to test the association between cagA gene and gastric complications.ResultsCagA gene was detected in 20/37(54%) of the samples that were found positive for H. pylori. There was no association between endoscopy finding and the presence of the cagA gene (p = 0.225). Specific amino acid variations were found at seven loci related to strains from a patient with duodenitis, gastric ulcer, and gastric atrophy (R448H, T457K, S460L, IT463-464VA, D470E, A482Q, KNV490-491-492TKT) while mutations in cancerous strain were A439P, T457P, and H500Y.ConclusionDisease-specific variations of cagA of H. pylori strains, in the region of amino acid residues 428-510, were evident among Sudanese patients with different gastroduodenal diseases. A novel mutation (K458N) was detected in a patient with duodenitis, which affects the positive electrostatic surface of cagA. Phylogenetic analysis showed a high level of diversity of cagA from Sudanese H. pylori strains.

scholarly journals Evaluation of Better Staining Method among Hematoxylin and Eosin, Giemsa and Periodic Acid Schiff-Alcian Blue for the Detection of Helicobacter pylori in Gastric Biopsies

2020 ◽  
Vol 27 (5) ◽  
pp. 53-61
Author(s):  
Abdullah Saleh Alkhamiss
Keyword(s):  
Helicobacter Pylori ◽  
Alcian Blue ◽  
National Guard ◽  
Periodic Acid ◽  
Giemsa Stain ◽  
Periodic Acid Schiff ◽  
Gastric Biopsies ◽  
Hematoxylin And Eosin ◽  
H Pylori ◽  
Sensitivity Specificity

Background: This study was undertaken to evaluate the preferred method (Giemsa or periodic acid Schiff-Alcian blue [PAS-AB] stains) of detecting Helicobacter pylori (H. pylori) in gastric mucosal biopsies in terms of sensitivity, specificity and applicability. To the best of my knowledge, this is the first report comparing Giemsa and PAS-AB staining for the detection of H. pylori in such biopsies. Methods: The formalin-fixed paraffin-embedded blocks of 49 gastric biopsies from different patients were collected from the archive of anatomical pathology at King Abdulaziz Medical City, National Guard, Riyadh, Saudi Arabia. From each block, three slides were prepared and analysed using the hematoxylin and eosin (H&E), Giemsa and PAS-AB stains to detect the presence/absence of H. pylori, and the results were compared in terms of sensitivity, specificity and applicability. Results: The majority of the biopsies in this study showed antrum-type gastric mucosa. Only 15 biopsies showed active gastritis, whereas the rest showed chronic gastritis. Three biopsies showed intestinal metaplasia. All were detected by PAS-AB stain, but only two-thirds were detected by H&E stain. Fifteen gastric biopsies showed H. pylori infection in general and in 13 of them, active gastritis cases were discovered. Fourteen out of these 15 H. pylori infection cases were detected by Giemsa stain, whereas only 13 cases were detected by H&E stain. PAS-AB stain showed the worst results since it demonstrated only 40% sensitivity and 67.65% specificity in H. pylori detection. Conclusion: Giemsa stain has better sensitivity and specificity in gastric H. pylori infection detection than PAS-AB. Therefore, using PAS-AB stain to detect H. pylori infection is not recommended.

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