Premium
Profile of Expression of Helicobacter pylori γ‐Glutamyltranspeptidase
Author(s) -
Wachino JunIchi,
Shibayama Keigo,
Suzuki Satowa,
Yamane Kunikazu,
Mori Shigetarou,
Arakawa Yoshichika
Publication year - 2010
Publication title -
helicobacter
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.206
H-Index - 79
eISSN - 1523-5378
pISSN - 1083-4389
DOI - 10.1111/j.1523-5378.2010.00755.x
Subject(s) - microbiology and biotechnology , messenger rna , transcription (linguistics) , biology , primer extension , gene , gene expression , northern blot , start codon , western blot , biochemistry , philosophy , linguistics
Background: Helicobacter pylori produces γ‐glutamyltranspeptidase (GGT), a potential virulence factor involved in induction of host cell apoptosis. Regulation of the production of this protein is not known. Methods: The transcription start sites were determined by primer extension analysis. Transcription level of the GGT gene was examined by measuring the mRNA by RT‐PCR and expression level of GGT protein was examined by Western blot analysis under different conditions. Results: Two transcription start sites were identified; thymine at 78‐bp upstream and adenine at 79‐bp upstream from the ATG codon of the GGT gene. There was a possible ‐10 consensus promoter sequence (ATTAAT), but no apparent ‐35 consensus sequence was found. The transcription of the mRNA and the expression of the protein were at almost constant level during the course of culture. The mRNA level increased by exposure to low pH; however, the actual protein expression level remained almost constant. Addition of glutamine or glutamate did not affect the mRNA level and the protein expression level to a remarkable degree, nor did co‐culture with AGS cells affect the GGT activity level. Conclusion: It was suggested that H. pylori GGT is constitutively expressed under various conditions.