The gene encoding urease subunit A (ureA) of Helicobacter pylori (H.pylori) was cloned from H.pylori isolate by polymerase chain reaction (PCR). Sterile distilled water instead of DNA served as negative control. The n...The gene encoding urease subunit A (ureA) of Helicobacter pylori (H.pylori) was cloned from H.pylori isolate by polymerase chain reaction (PCR). Sterile distilled water instead of DNA served as negative control. The nucleotide sequence of the amplified product was determined. Homologous analysis of the ureA against that reported by Clayton CL and the GenBank and SwissProt databases were performed with the BLAST program at the Genome Net through the Internet. 0.8 kb PCR product was amplified from all H.pylori clinical isolators. The nucleotide sequence of the ureA was determined. The nucleotide sequence of the ureA began with ATG as the initiation codon and terminated in TAA as stop codon. The coding regions had a 44 % G+C content. The DNA sequence was 98 % homologous to that reported by Clayton CL (688 out of 702 residues were identical). The derived amino acid sequences of the ureA were 99 % homologous to that reported by Clayton CL (232 out of 234 residues were identical). The nucleotide sequence and the predicted protein showed significant homology to ureA of H.pylori in the NCBI Entrez database.展开更多
Summary: The vacuolated effect of Helicobacter (H. pylori) and its relationship to vacuolated cytotoxin antigen (VacA) were investigated by the method of cytotoxic test and SDS-pobyacrylamide gel electrophoresis (SDS-...Summary: The vacuolated effect of Helicobacter (H. pylori) and its relationship to vacuolated cytotoxin antigen (VacA) were investigated by the method of cytotoxic test and SDS-pobyacrylamide gel electrophoresis (SDS-PAGE). Of the 62 clinical isolates, the broth culture filter (BCF) of 43 strains caused the Vero cell intracytoplasmically vacuolated. H. pylori strains were divided into H. pylori (Toxin +) group with vacuolated effect and H. pylori (Toxin -) group without vacuolated effect. The analysis of the BCF of H. pylori (Toxin +) and that of H. pylori (Toxin -) was studied by SDS-PAGE and Scan reader. A kind of protein with 87 ku molecular weight was recognized in the BCF of 30.23 % (13/43) H. pylori (Toxin +) strains but in none of that of H. pylori (Toxin -) strains, the difference was statistically significant (P<0.05). There was a significant and concordant relationship between OD of the protein band with 87 ku molecular weight and titer of vacuolated activity of H. pylori(Toxin +) (r=0.67 and P<0.05 by linear regression analysis). H. pylori strains were divided into H. pylori (Toxin +) group with vacuolated effect and H. pylori (Toxin -) group without vacuolated effect. The vacuolated effect of H. pylori (Toxin +) was caused by the protein with 87 ku molecular weight (VacA)展开更多
文摘The gene encoding urease subunit A (ureA) of Helicobacter pylori (H.pylori) was cloned from H.pylori isolate by polymerase chain reaction (PCR). Sterile distilled water instead of DNA served as negative control. The nucleotide sequence of the amplified product was determined. Homologous analysis of the ureA against that reported by Clayton CL and the GenBank and SwissProt databases were performed with the BLAST program at the Genome Net through the Internet. 0.8 kb PCR product was amplified from all H.pylori clinical isolators. The nucleotide sequence of the ureA was determined. The nucleotide sequence of the ureA began with ATG as the initiation codon and terminated in TAA as stop codon. The coding regions had a 44 % G+C content. The DNA sequence was 98 % homologous to that reported by Clayton CL (688 out of 702 residues were identical). The derived amino acid sequences of the ureA were 99 % homologous to that reported by Clayton CL (232 out of 234 residues were identical). The nucleotide sequence and the predicted protein showed significant homology to ureA of H.pylori in the NCBI Entrez database.
基金This work was supported by a grant from National NaturalScience Foundation of China(No. 395 70 334 )
文摘Summary: The vacuolated effect of Helicobacter (H. pylori) and its relationship to vacuolated cytotoxin antigen (VacA) were investigated by the method of cytotoxic test and SDS-pobyacrylamide gel electrophoresis (SDS-PAGE). Of the 62 clinical isolates, the broth culture filter (BCF) of 43 strains caused the Vero cell intracytoplasmically vacuolated. H. pylori strains were divided into H. pylori (Toxin +) group with vacuolated effect and H. pylori (Toxin -) group without vacuolated effect. The analysis of the BCF of H. pylori (Toxin +) and that of H. pylori (Toxin -) was studied by SDS-PAGE and Scan reader. A kind of protein with 87 ku molecular weight was recognized in the BCF of 30.23 % (13/43) H. pylori (Toxin +) strains but in none of that of H. pylori (Toxin -) strains, the difference was statistically significant (P<0.05). There was a significant and concordant relationship between OD of the protein band with 87 ku molecular weight and titer of vacuolated activity of H. pylori(Toxin +) (r=0.67 and P<0.05 by linear regression analysis). H. pylori strains were divided into H. pylori (Toxin +) group with vacuolated effect and H. pylori (Toxin -) group without vacuolated effect. The vacuolated effect of H. pylori (Toxin +) was caused by the protein with 87 ku molecular weight (VacA)
