RESUMO
<p><b>OBJECTIVE</b>To clone UreB gene of Helicobacter pylori (H. pylori) isolated from children to pGEX-4T-1 expression plasmid, and do sequence analysis.</p><p><b>METHODS</b>A pair of specific primer was designed according to H. pylori UreB gene in the GenBank. Using H. pylori strains isolated from children as a template, a UreB gene was obtained by PCR. After EcoR I and Not I digestion, the PCR production was linked with pGEX-4T-1 which was digested with the same enzymes. The recombinant plasmid was transformed into E.coli BL21 and identified by double enzyme digestion and sequence analysis. The sequence results were compared with the gene sequence in the GenBank.</p><p><b>RESULTS</b>A UreB gene was successfully amplified from children's H. pylori strain GZCH1. It was 1710 bp in size. The objective band was identified by double enzyme digestion. DNA sequence showed that UreB was in the correct open reading frame. The sequence comparison analysis showed that DNA and amino acid sequence identities of UreB gene with other strains were 98%. The sequence of UreB of H. pylori strain GZCH1 was submitted to GenBank (accession number:FJ455126).</p><p><b>CONCLUSIONS</b>UreB of H. pylori strain GZCH1 is successfully cloned to pGEX-4T-1, which provides a basis for research of oral H. pylori vaccine.</p>