Comparative genomics of Helicobacter pylori isolates recovered from ulcer disease patients in England

Pathogen Evolution Group, Laboratory of Molecular and Cell Biology, Centre for DNA Fingerprinting and Diagnostics (CDFD), Hyderabad, India.
BMC Microbiology (Impact Factor: 3.1). 03/2005; 5(32):1-10. DOI: 10.1186/1471-2180-5-32
Source: OAI

ABSTRACT Background . Genomic diversity of H. pylori from many different human populations is largely unknown. We compared genomes of 65 H. pylori strains from Nottingham, England. Molecular analysis was carried out to identify rearrangements within and outside the cag -pathogenicity-island ( cag PAI) and DNA sequence divergence in candidate genes. Phylogenetic analysis was carried out based on various high-resolution genotyping techniques.

Results . Analyses of virulence genes ( cag T, cag E, cag A, vac A, ice A, oip A and bab B) revealed that H. pylori strains from England are genetically distinct from strains obtained from other countries. The toxigenic vac A s1m1 genotype was found to be less common and the plasticity region cluster was found to be disrupted in all the isolates. English isolates showed a predominance of ice A1 alleles and a functional proinflammatory oip A gene. The English H. pylori gene pool revealed several Asian/oriental features. This included the predominance of cag A – glr ( cag A right junction) motif types III and II (up to 42%), presence of vac A m1c alleles and phylogenetic affinity towards East Asian / Amerindian gene pools based on fluorescent amplified fragment length polymorphism (FAFLP) analysis and glm M sequence analysis.

Conclusion . Overall, our results demonstrated genetic affinities of H. pylori in England with both European and the Asian gene pools and some distinctive genetic features of virulence genes that may have evolved in this important European population.

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    ABSTRACT: There is not much information available regarding the prevalence of the genotypes of Helicobacter pylori isolates in Turkey, particularly in eastern Turkey. The aims of this study were to detect the prevalence of different genotypes of H. pylori in Turkish patients with gastrointestinal complaints and to determine the relationship of these genotypes with clinical outcome and sex. One hundred forty H. pylori isolates were examined for the presence of its genotypes by the PCR. We found that the prevalence of vacAs1,vacAs2, cagA, cagE, iceA1, iceA2 and babA2 genes were 88.6%, 11.4%, 71.4%, 35.7%, 41.4%, 58.6%, and 62.1%, respectively. The most predominant vacA subtype was s1a (81.4%). The most vacA allelic combination detected were vacAs1m1 (65.2%) and s1m2 (53.9%) in patients with peptic ulcer and gastritis, respectively. The only vacAs1 isolate was significantly associated with gastritis and peptic ulcer (p<0.05). The vacAs1a, ml, slml and babA2 genes were significantly associated with peptic ulcer (p<0.05), whereas m2 gene was significantly associated with only gastritis (p<0.05). The difference between sex and genotypes was statistically significant among the cagA,vacAs1, iceA2 and babA2 genes. This study reported for the first time the prevalence of H. pylori genotypes in patients with gastrointestinal complaints in eastern Turkey. Further studies are needed to understand epidemiological importance of the genotypes of H. pylori isolates in this region and the association between the virulence genes and clinical outcome in different regions.
    Brazilian Journal of Microbiology 10/2012; 43(4):1332-9. · 0.76 Impact Factor
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    ABSTRACT: Gastroenterología RESUMEN Helicobacter pylori es una bacteria con forma helicoidal, que vive únicamente en el estómago humano. Aunque la relación del bacilo con el epitelio es de antaño debido a que gran parte de la población se halla colonizada, tan solo cerca del 10% de las personas infectadas desarrollan ciertas patologías, entre ellas la úlcera duodenal, el adenocarcinoma estomacal y el linfoma tipo MALT. En las últimas décadas, la investigación sobre el Helicobacter pylori se ha incrementado, y poco a poco, se ha deslumbrando más sobre la fi siopatología de este microorganismo, como la presencia de genes involucrados en la patogenicidad vacA, cagA babA y sabA, indicando con ello que no es precisamente una bacteria totalmente inocua, pero tampoco el del mayor patógeno en el epitelio estomacal. Mediante la presente revisión se pretende abarcar algunos aspectos sobre la bacteria, su relación y benefi cios con el huésped, así como los procesos patológicos que puede desencadenar su accionar. (MÉD.UIS. 2011;24(3):287-96). Palabras Clave: Helicobacter pylori. Úlcera péptica. Linfoma tipo MALT. Linfoma de Células B de la Zona Marginal. SUMMARY Helicobacter pylori: review of physiologic and patologic aspects Helicobacter pylori is a spiral-shaped bacterium, that lives only in the human stomach. Although the relationship of the bacillus in the epithelium has been since ancient because most of the population is colonized, only about 10% of infected people develop certain diseases, including duodenal ulcer, stomach adenocarcinoma and lymphoma MALT. In recent decades, research on Helicobacter pylori has increased, and little by little, has dazzled more about the pathophysiology of this organism, as the presence of genes involved in pathogenicity vacA, cagA, babA and sabA thereby indicating that is just a completely harmless bacteria, but neither of the major pathogen in stomach epithelium. Through this review is to cover some aspects of the bacteria, their relationship and benefi ts to the host and the pathological processes that can trigger their actions. (MÉD.UIS. 2011;24(3):287-96) Key Words: Helicobacter pylori. Peptic ulcer. Lymphoma MALT. Lymphoma. B-Cell. Marginal Zone. INTRODUCCIÓN El Helicobacter pylori (H. pylori) al microscopio óptico y con el uso de colorantes tales como hematoxilina-eosina, tinción de Warthin-Starry o el Giemsa modificada 1 , se observa en medios orgánicos como un bacilo gram negativo con forma curvilínea y multiflagelado cuyo tamaño varía a lo ancho entre 0,5 a 1 µm y a lo largo desde 2,5 hasta 6,5 µm, omitiendo el tamaño de los flagelos que pueden ser de hasta 30 µm 1-3 . El estudio el 20 de agosto de 2011 y aceptado para publicación el 3 de diciembre de 2011.
    Medicas UIS. 06/2011; 24(3-24):287.
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    ABSTRACT: The aims of our work were to determine the presence of the cag pathogenicity-island (cag PAI) and other virulence genes of Helicobacter pylori recovered from patients with gastritis and peptic ulcer, and to investigate the correlation of these virulence genes with clinical outcome. The presence of the cagA, the promoter regions of cagA, cagE, cagT, and the left end of cag-PAI (LEC), cag right junction (cagRJ), the plasticity region open reading frames (ORFs), vacA and oipA genes among 69 H. pylori isolates were determined by polymerase chain reaction. Intact cag PAI was detected in only one (1.4%) isolate. The cagA gene was identified in 52.1% and 76.2% of isolates from patients with dyspepsia (gastritis and peptic ulcer), respectively. The plasticity region ORFs i.e. JHP912 and JHP931 were predominantly detected in isolates from peptic ulcer. Less than 25% of the isolates carried other ORFs. Types I, II and III were the most commonly found among the isolates. None of the isolates possessed type Ib, 1c, IIIb, IV and V motifs. The most commonly vacA genotypes were s1am1a and s1m2 in isolates with peptic ulcer and gastritis, respectively. The results confirmed that the prevalence of oipA (Hp0638) gene was 75% and 85.7% in patients with gastritis and peptic ulcer, respectively. Furthermore, vacA s1am1a positivity was significantly related to peptic ulcer (p < 0.05).
    Brazilian journal of microbiology : [publication of the Brazilian Society for Microbiology]. 12/2013; 44(4):1267-74.

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