Article
Immunology
Sirena C. Tran, Mark S. Mcclain, Timothy L. Cover
Summary: Helicobacter pylori strains containing the cag pathogenicity island (PAI) are associated with the development of gastric adenocarcinoma and peptic ulcer disease. The cag PAI encodes a secreted effector protein (CagA) and a type IV secretion system (Cag T4SS). This study investigated the role of the CagY antenna region in Cag T4SS OMCC assembly and function.
INFECTION AND IMMUNITY
(2023)
Article
Multidisciplinary Sciences
Yasaman Azizimoghaddam, Sadaf Kermanpour, Nasrin Mirzaei, Hamidreza Houri, Ali Nabavi-Rad, Hamid Asadzadeh Aghdaei, Abbas Yadegar, Mohammad Reza Zali
Summary: The prevalence of cagI and cagN genes in Iranian H. pylori isolates was high, but there was no significant correlation with clinical diseases.
SCIENTIFIC REPORTS
(2023)
Article
Cell Biology
Irshad Sharafutdinov, Steffen Backert, Nicole Tegtmeyer
Summary: This study found that Helicobacter pylori infection induces overexpression of cortactin at the protein level. The upregulation of cortactin requires the involvement of T4SS and effector protein CagA. Ectopic expression of CagA is sufficient to stimulate cortactin overexpression.
CELLULAR MICROBIOLOGY
(2021)
Article
Biophysics
Sa Xiao, Lei Zhang, Xiaolei Wang, Wenjuan Li, Xia Wang
Summary: A novel Cag4-double nanoporous gold biosensor was constructed for screening Cag4 allosteric regulators, providing a fast and useful platform for potential drug discovery.
BIOSENSORS & BIOELECTRONICS
(2023)
Review
Microbiology
Victor E. Reyes
Summary: Helicobacter pylori infection is a major risk factor for gastric cancer and is associated with chronic inflammation and DNA damage. Understanding the mechanisms of H. pylori-induced carcinogenesis and immune evasion is crucial for preventing gastric cancer and reducing the burden of this disease.
Article
Biochemistry & Molecular Biology
Jacky Lu, Kathryn P. Haley, Jamisha D. Francis, Miriam A. Guevara, Ryan S. Doster, Kelly M. Craft, Rebecca E. Moore, Schuyler A. Chambers, Alberto G. Delgado, Maria Blanca Piazuelo, Steven M. Damo, Steven D. Townsend, Jennifer A. Gaddy
Summary: Chronic infection with Helicobacter pylori increases the risk of gastric diseases, including gastric cancer, with strains encoding the cag T4SS system being associated with more serious disease outcomes. The presence of nutrient iron can modulate the activity of the T4SS and biogenesis of T4SS pili, with lactoferrin exerting antimicrobial activity against H. pylori under iron-limited conditions. Additionally, culturing H. pylori with holo-lactoferrin prior to co-culture with gastric epithelial cells can lead to repression of the cag T4SS activity and decreased biogenesis of T4SS pili.
Article
Biochemistry & Molecular Biology
Clara Lettl, Rainer Haas, Wolfgang Fischer
Summary: Type IV secretion of effector proteins is crucial for interaction of human pathogens with target cells, with the example of CagA effector protein produced by Helicobacter pylori. A novel split luciferase-based translocation reporter system was developed to study the kinetics and mode of action of CagA type IV secretion, showing rapid injection of CagA into gastric epithelial cells by H. pylori cells. It was found that unfolding of effector proteins is necessary for transport, providing new insights into the translocation mechanisms of pathogenic bacteria.
MOLECULAR MICROBIOLOGY
(2021)
Article
Biochemistry & Molecular Biology
Manouchehr Ahmadi Hedayati, Delniya Khani, Hamed Bashiri
Summary: This study investigated the correlation between H. pylori virulence genes and Fgf7 gene expression in gastric antral epithelial cells. The results showed that H. pylori infection and pathogenic genes were positively correlated with Fgf7 gene expression, suggesting a potential involvement of H. pylori infection in gastric cancer development through the regulation of Fgf7 expression.
MOLECULAR BIOLOGY REPORTS
(2022)
Article
Biochemistry & Molecular Biology
Rejina Shrestha, Naoko Murata-Kamiya, Satoshi Imai, Masami Yamamoto, Tetsuya Tsukamoto, Sachiyo Nomura, Masanori Hatakeyama
Summary: The initial step in bacterial infection is the adherence of the bacterium to the target cell surface. This study found that the mouse stomach has a much lower expression level of Ceacam1 compared to the human stomach, which leads to the inability of the bacteria to deliver the CagA protein due to the lack of interaction between HopQ and Ceacam1 in mouse gastric epithelial cells.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2022)
Article
Immunology
Larissa Faass, Saskia C. Stein, Martina Hauke, Madeleine Gapp, Manuel Albanese, Christine Josenhans
Summary: The study reveals that Helicobacter pylori activates human phagocytic cells through heptose metabolites, triggering early inflammatory responses in Thp-1 cells and human primary macrophages. The activation is primarily dependent on bacterial LPS inner core heptose metabolites, with a significant contribution of an active CagT4SS.
FRONTIERS IN IMMUNOLOGY
(2021)
Article
Multidisciplinary Sciences
Xiuling Wu, Yanhe Zhao, Hong Zhang, Wendi Yang, Jinbo Yang, Lifang Sun, Meiqin Jiang, Qin Wang, Qianchao Wang, Xianren Ye, Xuewu Zhang, Yunkun Wu
Summary: This study presents the crystal structures of Cag beta and its complex with CagZ, revealing the regulatory mechanisms of Cag beta in delivering the CagA effector. The binding of CagZ to Cag beta prevents the formation of the hexameric assembly required for ATPase activity, thus inhibiting Cag beta and regulating CagA transport.
NATURE COMMUNICATIONS
(2023)
Article
Multidisciplinary Sciences
Bui Hoang Phuc, Vo Phuoc Tuan, Ho Dang Quy Dung, Tran Thanh Binh, Pham Huu Tung, Tran Dinh Tri, Ngo Phuong Minh Thuan, Vu Van Khien, Tran Thi Huyen Trang, Junko Akada, Takeshi Matsumoto, Yoshio Yamaoka
Summary: The acquisition of tfs3/4 ICE was common in H. pylori strains in patients with gastroduodenal disease in Vietnam, and the complete cluster of tfs3 ICE was a reliable marker for the severity of disease in the H. pylori infected population.
SCIENTIFIC REPORTS
(2021)
Review
Medicine, General & Internal
Shamshul Ansari, Yoshio Yamaoka
Summary: H. pylori infection is associated with gastric mucosal diseases and gastric cancer, and animal models are useful for studying the pathophysiology of these complications.
JOURNAL OF CLINICAL MEDICINE
(2022)
Review
Immunology
Larissa Faass, Martina Hauke, Saskia C. Stein, Christine Josenhans
Summary: H. pylori is a human pathogen that has evolved specific host interaction biology through thousands of years of coevolution with its host. The molecular mechanisms of H. pylori's interaction with immune cells in the human system, particularly myeloid cells, are not well understood. Recent research has focused on the role of bacterial cell envelope metabolites and the H. pylori Cag type IV secretion system in activating and modulating cell responses. This review provides an overview of the current understanding of H. pylori's interaction with diverse human cell types, with a focus on bacterial metabolites and myeloid cells.
CURRENT OPINION IN IMMUNOLOGY
(2023)
Article
Oncology
Hyung-Suk Yoon, Xiao-Ou Shu, Hui Cai, Wei Zheng, Jie Wu, Wanqing Wen, Regina Courtney, Chris Shidal, Tim Waterboer, William J. Blot, Qiuyin Cai
Summary: This study found an association between Helicobacter pylori infection and lung cancer risk, which may be related to specific H. pylori antigens. The association between H. pylori infection and lung cancer risk may be more evident among African Americans and may be modified by smoking habits.
