Masatomo Kawakubo1, Kazuki Horiuchi2, Takehisa Matsumoto3, Jun Nakayama1, Taiji Akamatsu4, Tsutomu Katsuyama5, Hiroyoshi Ota6, Junji Sagara6. 1. Department of Molecular Pathology, Shinshu University Graduate School of Medicine, Matsumoto, Japan. 2. Department of Laboratory Medicine, Shinshu University Hospital, Matsumoto, Japan. 3. Department of Laboratory Sciences, Gunma University Graduate School of Health Sciences, Maebashi, Japan. 4. Endoscopy Center, Suzaka Hospital, Nagano Prefectural Shinshu Medical Center, Suzaka, Japan. 5. Maruko Central Hospital, Ueda, Japan. 6. Department of Biomedical Laboratory Science, School of Health Sciences, Shinshu University, Matsumoto, Japan.
Abstract
BACKGROUND: Non-Helicobacter pylori helicobacters (NHPHs) besides H. pylori infect human stomachs and cause chronic gastritis and mucosa-associated lymphoid tissue lymphoma. Cholesteryl-α-glucosides have been identified as unique glycolipids present in H. pylori and some Helicobacter species. Cholesterol-α-glucosyltransferase (αCgT), a key enzyme for the biosynthesis of cholesteryl-α-glucosides, plays crucial roles in the pathogenicity of H. pylori. Therefore, it is important to examine αCgTs of NHPHs. MATERIALS AND METHODS: Six gastric NHPHs were isolated from Japanese patients and maintained in mouse stomachs. The αCgT genes were amplified by PCR and inverse PCR. We retrieved the αCgT genes of other Helicobacter species by BLAST searches in GenBank. RESULTS: αCgT genes were present in most Helicobacter species and in all Japanese isolates examined. However, we could find no candidate gene for αCgT in the whole genome of Helicobacter cinaedi and several enterohepatic species. Phylogenic analysis demonstrated that the αCgT genes of all Japanese isolates show high similarities to that of a zoonotic group of gastric NHPHs including Helicobacter suis, Helicobacter heilmannii, and Helicobacter ailurogastricus. Of 6 Japanese isolates, the αCgT genes of 4 isolates were identical to that of H. suis, and that of another 2 isolates were similar to that of H. heilmannii and H. ailurogastricus. CONCLUSIONS: All gastric NHPHs examined showed presence of αCgT genes, indicating that αCgT may be beneficial for these helicobacters to infect human and possibly animal stomachs. Our study indicated that NHPHs could be classified into 2 groups, NHPHs with αCgT genes and NHPHs without αCgT genes.
BACKGROUND: Non-Helicobacter pylori helicobacters (NHPHs) besides H. pylori infect human stomachs and cause chronic gastritis and mucosa-associated lymphoid tissue lymphoma. Cholesteryl-α-glucosides have been identified as unique glycolipids present in H. pylori and some Helicobacter species. Cholesterol-α-glucosyltransferase (αCgT), a key enzyme for the biosynthesis of cholesteryl-α-glucosides, plays crucial roles in the pathogenicity of H. pylori. Therefore, it is important to examine αCgTs of NHPHs. MATERIALS AND METHODS: Six gastric NHPHs were isolated from Japanese patients and maintained in mouse stomachs. The αCgT genes were amplified by PCR and inverse PCR. We retrieved the αCgT genes of other Helicobacter species by BLAST searches in GenBank. RESULTS: αCgT genes were present in most Helicobacter species and in all Japanese isolates examined. However, we could find no candidate gene for αCgT in the whole genome of Helicobacter cinaedi and several enterohepatic species. Phylogenic analysis demonstrated that the αCgT genes of all Japanese isolates show high similarities to that of a zoonotic group of gastric NHPHs including Helicobacter suis, Helicobacter heilmannii, and Helicobacter ailurogastricus. Of 6 Japanese isolates, the αCgT genes of 4 isolates were identical to that of H. suis, and that of another 2 isolates were similar to that of H. heilmannii and H. ailurogastricus. CONCLUSIONS: All gastric NHPHs examined showed presence of αCgT genes, indicating that αCgT may be beneficial for these helicobacters to infect human and possibly animal stomachs. Our study indicated that NHPHs could be classified into 2 groups, NHPHs with αCgT genes and NHPHs without αCgT genes.