Construction of a prokaryotic expression system of vacA gene and detection of vacA gene, VacA protein in Helicobacter pylori isolates and ant-VacA antibody in patients’ sera

Figure 1 The target amplification products with whole length of vacA gene from H pylori strain NCTC11637 and partial frag-ment of vacA gene from a H pylori isolate. Lane 1, DNA marker; lane 2, an amplification fragment of complete vacA gene from H pylori strain NCTC11637; lane 4, an amplification fragment of partial vacA gene from a H pylori isolate; and lanes 3 and 5, blank controls.