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Single-step PCR amplification and enzyme restriction analysis of the entire Helicobacter pylori cytotoxin vacA gene for genetic variability studies.

Centro de Investigación sobre Enfermedades Infecciosas, Instituto Nacional de Salud Pública, Cuernavaca, Mor, Mexico.
FEMS Microbiology Letters (Impact Factor: 2.72). 09/1999; 178(1):55-62. DOI: 10.1111/j.1574-6968.1999.tb13759.x
Source: PubMed

ABSTRACT To monitor changes along the entire Helicobacter pylori vac A gene we carried out full-length single-step PCR amplification in 21 gastritis and gastric cancer isolates. HindIII restriction analysis led us to detect a > 400-bp internal insertion in vacA subsequently shown to be a direct 451-bp gene duplication. We found HindIII profiles for 16 genes that allowed their grouping into two restriction patterns that were related to theoretical profiles for previously sequenced Western genes. Comparisons with theoretical HindIII patterns for Japanese isolates appear suggestive of geographical H. pylori clonality. Full-length single-step PCR amplification seems suitable for quick restriction pattern assignment and detection of gene size changes.

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Available from: Roberto Herrera-Goepfert, Apr 30, 2015
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    • "To analyze how VacA cytotoxin affects AGS cells, we used two strains: the VacA1 2074-Cd (s1/m1) strain and the 4767-C (s1/m1) strain, which presents a duplication of 451 base pairs from the codon 459 through to 594 (Perales et al., 1999). This duplication creates a stop codon nine base pairs downstream from the point of insertion and due to that, a truncated protein of 606 amino acids would be produced. "
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