Microevolution between paired antral and paired antrum and corpus Helicobacter pylori isolates recovered from individual patients

2004 ◽  
Vol 53 (7) ◽  
pp. 669-677 ◽  
Author(s):  
Ian M. Carroll ◽  
Niyaz Ahmed ◽  
Sarah M. Beesley ◽  
Aleem A. Khan ◽  
Sheikh Ghousunnissa ◽  
...  

Sequence variations located at the signal sequence and mid-region within the vacA gene, the 3′-end of the cagA gene, the indel motifs at the 3′-end of the cag pathogenicity island and the regions upstream of the vacA and ribA genes were determined by PCR in 19 paired antral or antrum and corpus Helicobacter pylori isolates obtained at the same endoscopic session, and three antral pairs taken sequentially. Random amplification of polymorphic DNA (RAPD)-PCR and fluorescent amplified fragment length polymorphism (FAFLP)-PCR fingerprinting were applied to these paired clinical isolates. The FAFLP-PCR profiles generated were phylogenetically analysed. For the 22 paired isolates there were no differences within pairs at five of the genetic loci studied. However, six pairs of isolates (27 %), of which four were antrum and corpus pairs, showed differences in the numbers of repeats located at the 3′-end of the cagA gene. RAPD-PCR fingerprinting showed that 16 (73 %) pairs, nine of which were antrum and corpus pairs, possessed identical profiles, while six (27 %) displayed distinctly different profiles, indicating mixed infections. Three of the six pairs showing differences at the 3′-end of the cagA gene yielded identical RAPD-PCR fingerprints. FAFLP-PCR fingerprinting and phylogenetic analysis revealed that all 16 pairs that displayed identical RAPD-PCR profiles had highly similar, but not identical, fingerprints, demonstrating that these pairs were ancestrally related but had undergone minor genomic alterations. Two antrum and corpus pairs of isolates, within the latter group, were isolates obtained from two siblings from the same family. This analysis demonstrated that each sibling was colonized by ancestrally related strains that exhibited differences in vacA genotype characteristics.

2002 ◽  
Vol 68 (8) ◽  
pp. 4140-4144 ◽  
Author(s):  
Tomoo Sawabe ◽  
Fabiano L. Thompson ◽  
Jeroen Heyrman ◽  
Margo Cnockaert ◽  
Karin Hayashi ◽  
...  

ABSTRACT When analyzed by fluorescent amplified fragment length polymorphism and repetitive extragenic palindrome-PCR fingerprinting, a total of 47 Vibrio halioticoli strains isolated from four Japanese abalone species and one turban shell species formed three clusters that roughly reflect the different species of host abalone from which they were isolated. The V. halioticoli isolates from turban shells were distributed evenly among the clusters. Representative isolates from two clusters were deemed separate species or subspecies by DNA-DNA hybridization.


2006 ◽  
Vol 73 (3) ◽  
pp. 1010-1013 ◽  
Author(s):  
Mai Ping Tan ◽  
Maria Kaparakis ◽  
Maja Galic ◽  
John Pedersen ◽  
Martin Pearse ◽  
...  

ABSTRACT We examined the impact of Helicobacter pylori infection on the murine gastric microbiota by culture and terminal-restriction fragment length polymorphism and found that neither acute nor chronic H. pylori infection substantially affected the gastric microbial composition. Interestingly, the total H. pylori burden detected by real-time PCR was significantly higher than that revealed by viable counts, suggesting that the antigenic load sustaining H. pylori-induced gastritis could be considerably higher than previously believed.


2003 ◽  
Vol 69 (8) ◽  
pp. 4658-4661 ◽  
Author(s):  
Pam Scates ◽  
Lynn Moran ◽  
Robert H. Madden

ABSTRACT Preston broth and agar incubated at either 37 or 42°C have been widely used to isolate campylobacters from foodstuffs. The consequences of using either incubation temperature were investigated. Retail packs of raw chicken (n = 24) and raw lamb liver (n = 30) were purchased. Samples were incubated in Preston broth at 37 and 42°C and then streaked onto Preston agar and incubated as before. Two Campylobacter isolates per treatment were characterized. Poultry isolates were genotyped by random amplification of polymorphic DNA (RAPD), pulsed-field gel electrophoresis (PFGE), and flagellin PCR-restriction fragment length polymorphism, and lamb isolates were genotyped by RAPD only. In total, 96% of the poultry and 73% of the lamb samples yielded campylobacters. The lamb isolates were all Campylobacter jejuni, as were 96% of the poultry isolates, with the remainder being Campylobacter lari. The incubation temperature had no significant effect on the number of positive samples or on the species isolated. However, genotyping of the C. jejuni isolates revealed profound differences in the types obtained. Overall (from poultry and lamb), the use of a single incubation temperature, 37°C, gave 56% of the total number of RAPD C. jejuni genotypes, and hence, 44% remained undetected. The effect was especially marked in the poultry samples, where incubation at 37°C gave 47% of the PFGE genotypes but 53% were exclusively recovered after incubation at 42°C. Thus, the incubation temperature of Preston media selects for certain genotypes of C. jejuni, and to detect the widest range, samples should be incubated at both 37 and 42°C. Conversely, genotyping results arising from the use of a single incubation temperature should be interpreted with caution.


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