JaLCDOI 10.18926/AMO/49667
FullText URL 67_2_93.pdf
Author Kita, Masahide| Yokota, Kenji| Okada, Hiroyuki| Take, Susumu| Takenaka, Ryuta| Kawahara, Yoshiro| Oguma, Keiji| Matsushita, Osamu| Yamamoto, Kazuhide|
Abstract Atrophy of the gastric mucosa is a precursor of intestinal-type gastric cancer, and Helicobacter pylori infection causes atrophic gastritis. The aim of this study was to determine whether the genetic diversity of H. pylori virulence genes is associated with the development and progression of gastric atrophy in humans. We isolated and cultured H. pylori strains from patients with gastric ulcer and duodenal ulcer accompanied by atrophic gastritis in background mucosa. H. pylori strains were stored at -80℃ prior to the experiments being carried out. We analyzed iceA, babA, vacA, cagA, and cagE genes by PCR. The cagA gene was analyzed through sequencing of the C-terminal region containing the EPIYA motif, which is related to tyrosine phosphorylation. Severe atrophy was observed in patients with gastric ulcer. The major phenotype of the vacA gene was s1c/m1 (93オ). The cagA gene was detected in all strains. The cagE gene was not detected in 2 and 5 strains from the mild cases and severe cases, respectively. The major cagA EPIYA motif, which is amino acids repeat in the C terminus, was the A-B-D type (44 of 58 strains). The virulence genes were not statistically associated with the severity of atrophy in the background gastric mucosa in humans. Not only identification of bacterial virulence factors but also studies of the host response will be necessary to investigate the progression of gastric atrophy and subsequent cancer development in humans.
Keywords Helicobacter pylori virulence genes chronic atrophic gastritis
Amo Type Original Article
Published Date 2013-04
Publication Title Acta Medica Okayama
Volume volume67
Issue issue2
Publisher Okayama University Medical School
Start Page 93
End Page 98
ISSN 0386-300X
NCID AA00508441
Content Type Journal Article
language 英語
Copyright Holders CopyrightⒸ 2013 by Okayama University Medical School
File Version publisher
Refereed True
PubMed ID 23603925
Web of Sience KeyUT 000317801700003
Related Url http://ousar.lib.okayama-u.ac.jp/metadata/52508
JaLCDOI 10.18926/AMO/49252
FullText URL 67_1_9.pdf
Author Fatmawati, Ni Nengah Dwi| Sakaguchi, Yoshihiko| Suzuki, Tomonori| Oda, Masataka| Shimizu, Kenta| Yamamoto, Yumiko| Sakurai, Jun| Matsushita, Osamu| Oguma, Keiji|
Abstract Clostridium botulinum type C and D strains recently have been found to produce PLC on egg yolk agar plates. To characterize the gene, enzymatic and biological activities of C. botulinum PLCs (Cb-PLCs), the cb-plc genes from 8 strains were sequenced, and 1 representative gene was cloned and expressed as a recombinant protein. The enzymatic and hemolytic activities of the recombinant Cb-PLC were measured and compared with those of the Clostridium perfringens alpha-toxin. Each of the eight cb-plc genes encoded a 399 amino acid residue protein preceded by a 27 residue signal peptide. The protein consists of 2 domains, the N- and C-domains, and the overall amino acid sequence identity between Cb-PLC and alpha-toxin was greater than 50%, suggesting that Cb-PLC is homologous to the alpha-toxin. The key residues in the N-domain were conserved, whereas those in the C-domain which are important in membrane interaction were different than in the alpha-toxin. As expected, Cb-PLC could hydrolyze egg yolk phospholipid, p-nitrophenylphosphorylcholine, and sphingomyelin, and also exhibited hemolytic activity;however, its activities were about 4- to over 200-fold lower than those of alpha-toxin. Although Cb-PLC showed weak enzymatic and biological activities, it is speculated that Cb-PLC might play a role in the pathogenicity of botulism or for bacterial survival.
Keywords botulinum phospholipase C botulinum toxin phospholipase C activity sphingomyelinase activity hemolytic activity
Amo Type Original Article
Published Date 2013-02
Publication Title Acta Medica Okayama
Volume volume67
Issue issue1
Publisher Okayama University Medical School
Start Page 9
End Page 18
ISSN 0386-300X
NCID AA00508441
Content Type Journal Article
language 英語
Copyright Holders CopyrightⒸ 2013 by Okayama University Medical School
File Version publisher
Refereed True
PubMed ID 23439504
Web of Sience KeyUT 000316829900002
Related Url http://ousar.lib.okayama-u.ac.jp/metadata/49731