Functional characterization of the Helicobacter pylori chaperone protein HP0795.
Trigger factor (TF) is one of the multiple bacterial chaperone proteins interacting with nascent peptides and facilitating their folding in bacteria. While TF is well-characterized in E. coli, HP0795, a TF-like homologue gene identified earlier in the pathogenic Helicobacter pylori (H. pylori), has not been studied biochemically to date. To characterize its function as a chaperone, we performed 3D-modeling, cross-linking and in vitro enzyme assays to HP0795 in vitro. Our results show that HP0795 possesses peptidyl prolyl cis-trans isomerase activity and exhibits a dimeric structure in solution. In addition, stable expression of HP0795 in a series of well-characterized E. coli chaperone-deficient strains rescued the growth defects in these mutants. Furthermore, we showed that the presence of HP0795 greatly reduced protein aggregation caused by deficiencies of chaperones in these strains. In contrast to other chaperone genes in H. pylori, gene expression of HP0795 displays little induction under acidic pH conditions. Together, our results suggest that HP0795 is a constitutively expressed TF-like protein of the prokaryotic chaperone family that may not play a major role in acid response. Given the pathogenic properties of H. pylori, our insights might provide new avenues for potential future medical intervention for H. pylori-related conditions.
State Key Laboratory of Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China.
Dongjie
D
Fan
School of Life Science and Technology, Harbin Institute of Technology, 2 Yikuang Street, Harbin, 150080, China; Beijing CapitalBio MedLab, 88 D2, Branch Six Street, Economic and Technological Development Zone, Beijing 101111, China.
Qiming
Q
Zhou
School of Life Science and Technology, Harbin Institute of Technology, 2 Yikuang Street, Harbin, 150080, China.
Chuanpeng
C
Liu
State Key Laboratory of Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China. Electronic address: zhangjianzhong@icdc.cn.
Jianzhong
J
Zhang
D001426:Bacterial Proteins / Q000737:chemistry / Q000378:metabolism*; D004926:Escherichia coli / Q000235:genetics / Q000254:growth & development; D015870:Gene Expression; D020869:Gene Expression Profiling; D005816:Genetic Complementation Test; D016480:Helicobacter pylori / Q000201:enzymology*; D006863:Hydrogen-Ion Concentration; D008958:Models, Molecular; D018832:Molecular Chaperones / Q000737:chemistry / Q000378:metabolism*; D019696:Peptidylprolyl Isomerase / Q000737:chemistry / Q000378:metabolism*; D011487:Protein Conformation; D055503:Protein Multimerization
D001426:Bacterial Proteins; D018832:Molecular Chaperones; D019696:Peptidylprolyl Isomerase
Chaperone; Helicobacter pylori; Peptidyl prolyl cis-trans isomerase; Trigger factor