Multiplex PCR for <i>vacA</i> subtypes, <i>cagA</i> and <i>cag</i> PAI empty site for the absence of <i>cag</i> PAI.

<p>M, 100 bp marker (New England Biolabs); lanes 1–10, single colonies isolated from PG207; C, 26695 for the first set (a) and AM1 (<i>cag</i> PAI negative strain) for the second set (b); N, Negative control (<i>E. coli</i> DNA). (a) Multiplex PCR showed this particular patient was infected by at least three different strains. Lanes 1–6 and lanes 9–10 showed existence of s2m2<i>cagA</i>⁻ strains, lane 7 showed existence of s1m1<i>cagA</i>⁻ strain and lane 8 showed existence of s1m1<i>cagA</i>⁺ strain. (b) All the single colonies, which failed to give amplicon for <i>cagA</i> gene, yielded ∼550 bp product for <i>cag</i> PAI empty site. The colony (Lane 8) that produced amplicon for <i>cagA</i> did not show any amplicon with primers for <i>cag</i> PAI empty site.