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Ronish LA, Biswas B, Bauer RM, Jacob ME, Piepenbrink KH. The role of extracellular structures in Clostridioides difficile biofilm formation. Anaerobe 2024; 88:102873. [PMID: 38844261 DOI: 10.1016/j.anaerobe.2024.102873] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2023] [Revised: 04/27/2024] [Accepted: 06/03/2024] [Indexed: 07/08/2024]
Abstract
C. difficile infection (CDI) is a costly and increasing burden on the healthcare systems of many developed countries due to the high rates of nosocomial infections. Despite the availability of several antibiotics with high response rates, effective treatment is hampered by recurrent infections. One potential mechanism for recurrence is the existence of C. difficile biofilms in the gut which persist through the course of antibiotics. In this review, we describe current developments in understanding the molecular mechanisms by which C. difficile biofilms form and are stabilized through extracellular biomolecular interactions.
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Affiliation(s)
- Leslie A Ronish
- Department of Biochemistry, University of Nebraska-Lincoln, Lincoln, NE, 68588, USA
| | - Baishakhi Biswas
- Department of Food Science and Technology, University of Nebraska-Lincoln, Lincoln, NE, 68588, USA
| | - Robert M Bauer
- Department of Biochemistry, University of Nebraska-Lincoln, Lincoln, NE, 68588, USA
| | - Mallory E Jacob
- Biochemistry Department, University of Geneva, Geneva, Switzerland
| | - Kurt H Piepenbrink
- Department of Biochemistry, University of Nebraska-Lincoln, Lincoln, NE, 68588, USA; Department of Food Science and Technology, University of Nebraska-Lincoln, Lincoln, NE, 68588, USA; Department of Chemistry, University of Nebraska-Lincoln, Lincoln, NE, 68588, USA; Nebraska Food for Health Center, University of Nebraska-Lincoln, Lincoln, NE, 68588, USA; Center for Integrated Biomolecular Communication, University of Nebraska-Lincoln, Lincoln, NE, 68588, USA.
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2
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Tohumcu E, Kaitsas F, Bricca L, Ruggeri A, Gasbarrini A, Cammarota G, Ianiro G. Helicobacter pylori and the Human Gastrointestinal Microbiota: A Multifaceted Relationship. Antibiotics (Basel) 2024; 13:584. [PMID: 39061266 PMCID: PMC11274338 DOI: 10.3390/antibiotics13070584] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2024] [Revised: 06/17/2024] [Accepted: 06/20/2024] [Indexed: 07/28/2024] Open
Abstract
Helicobacter pylori is a type of Gram-negative bacteria belonging to the Proteobacteria phylum which is known to cause gastrointestinal disorders such as gastritis and gastric ulcers. Its treatment is based on current eradication regimens, which are composed of combinations of antibiotics such as clarithromycin, metronidazole, levofloxacin and amoxicillin, often combined with a proton pump inhibitor (PPI). With the development of sequencing technologies, it has been demonstrated that not only does the colonization of the gastric and gut environment by H. pylori cause microbial changes, but also the treatment regimens used for its eradication have a significant altering effect on both the gastric and gut microbiota. Here, we review current knowledge on microbiota modulations of current therapies in both environments. We also summarize future perspectives regarding H. pylori infection, the integration of probiotics into therapy and what challenges are being faced on a global basis when we talk about eradication.
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Affiliation(s)
- Ege Tohumcu
- Department of Translational Medicine and Surgery, Università Cattolica del Sacro Cuore, Largo A. Gemelli 8, 00168 Rome, Italy; (E.T.); (F.K.); (A.R.); (A.G.); (G.C.)
- Department of Medical and Surgical Sciences, UOC Gastroenterologia, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, 00168 Rome, Italy
- Department of Medical and Surgical Sciences, UOC CEMAD Centro Malattie dell’Apparato Digerente, Medicina Interna e Gastroenterologia, Fondazione Policlinico Universitario Gemelli IRCCS, 00168 Rome, Italy
| | - Francesco Kaitsas
- Department of Translational Medicine and Surgery, Università Cattolica del Sacro Cuore, Largo A. Gemelli 8, 00168 Rome, Italy; (E.T.); (F.K.); (A.R.); (A.G.); (G.C.)
- Department of Medical and Surgical Sciences, UOC Gastroenterologia, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, 00168 Rome, Italy
- Department of Medical and Surgical Sciences, UOC CEMAD Centro Malattie dell’Apparato Digerente, Medicina Interna e Gastroenterologia, Fondazione Policlinico Universitario Gemelli IRCCS, 00168 Rome, Italy
| | - Ludovica Bricca
- Department of Surgical, Oncological and Gastroenterological Sciences (DiSCOG), Padua Univeristy, 35123 Padova, Italy;
| | - Alessandro Ruggeri
- Department of Translational Medicine and Surgery, Università Cattolica del Sacro Cuore, Largo A. Gemelli 8, 00168 Rome, Italy; (E.T.); (F.K.); (A.R.); (A.G.); (G.C.)
- Department of Medical and Surgical Sciences, UOC Gastroenterologia, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, 00168 Rome, Italy
- Department of Medical and Surgical Sciences, UOC CEMAD Centro Malattie dell’Apparato Digerente, Medicina Interna e Gastroenterologia, Fondazione Policlinico Universitario Gemelli IRCCS, 00168 Rome, Italy
| | - Antonio Gasbarrini
- Department of Translational Medicine and Surgery, Università Cattolica del Sacro Cuore, Largo A. Gemelli 8, 00168 Rome, Italy; (E.T.); (F.K.); (A.R.); (A.G.); (G.C.)
- Department of Medical and Surgical Sciences, UOC Gastroenterologia, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, 00168 Rome, Italy
- Department of Medical and Surgical Sciences, UOC CEMAD Centro Malattie dell’Apparato Digerente, Medicina Interna e Gastroenterologia, Fondazione Policlinico Universitario Gemelli IRCCS, 00168 Rome, Italy
| | - Giovanni Cammarota
- Department of Translational Medicine and Surgery, Università Cattolica del Sacro Cuore, Largo A. Gemelli 8, 00168 Rome, Italy; (E.T.); (F.K.); (A.R.); (A.G.); (G.C.)
- Department of Medical and Surgical Sciences, UOC Gastroenterologia, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, 00168 Rome, Italy
- Department of Medical and Surgical Sciences, UOC CEMAD Centro Malattie dell’Apparato Digerente, Medicina Interna e Gastroenterologia, Fondazione Policlinico Universitario Gemelli IRCCS, 00168 Rome, Italy
| | - Gianluca Ianiro
- Department of Translational Medicine and Surgery, Università Cattolica del Sacro Cuore, Largo A. Gemelli 8, 00168 Rome, Italy; (E.T.); (F.K.); (A.R.); (A.G.); (G.C.)
- Department of Medical and Surgical Sciences, UOC Gastroenterologia, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, 00168 Rome, Italy
- Department of Medical and Surgical Sciences, UOC CEMAD Centro Malattie dell’Apparato Digerente, Medicina Interna e Gastroenterologia, Fondazione Policlinico Universitario Gemelli IRCCS, 00168 Rome, Italy
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3
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Drnovsek J, Homan M, Zidar N, Smid LM. Pathogenesis and potential reversibility of intestinal metaplasia - a milestone in gastric carcinogenesis. Radiol Oncol 2024; 58:186-195. [PMID: 38643513 PMCID: PMC11165985 DOI: 10.2478/raon-2024-0028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Accepted: 03/19/2024] [Indexed: 04/23/2024] Open
Abstract
BACKGROUND Non-cardia gastric cancer remains a major cause of cancer-related mortality worldwide, despite declining incidence rates in many industrialized countries. The development of intestinal-type gastric cancer occurs through a multistep process in which normal mucosa is sequentially transformed into hyperproliferative epithelium, followed by metaplastic processes leading to carcinogenesis. Chronic infection with Helicobacter pylori is the primary etiological agent that causes chronic inflammation of the gastric mucosa, induces atrophic gastritis, and can lead to intestinal metaplasia and dysplasia. Both intestinal metaplasia and dysplasia are precancerous lesions, in which gastric cancer is more likely to occur. Atrophic gastritis often improves after eradication of Helicobacter pylori; however, the occurrence of intestinal metaplasia has been traditionally regarded as "the point of no return" in the carcinogenesis sequence. Helicobacter pylori eradication heals non-atrophic chronic gastritis, may lead to regression of atrophic gastritis, and reduces the risk of gastric cancer in patients with these conditions. In this article, we discuss the pathogenesis, epigenomics, and reversibility of intestinal metaplasia and briefly touch upon potential treatment strategy. CONCLUSIONS Gastric intestinal metaplasia no longer appears to be an irreversible precancerous lesion. However, there are still many controversies regarding the improvement of intestinal metaplasia after Helicobacter pylori eradication.
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Affiliation(s)
- Jan Drnovsek
- Department of Gastroenterology, University Medical Centre Ljubljana, Ljubljana, Slovenia
- Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
| | - Matjaz Homan
- Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
- Department of Gastroenterology, Hepatology and Nutrition, University Children’s Hospital, Ljubljana, Slovenia
| | - Nina Zidar
- Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
- Institute of Pathology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
| | - Lojze M Smid
- Department of Gastroenterology, University Medical Centre Ljubljana, Ljubljana, Slovenia
- Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
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4
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Sidner B, Lerma A, Biswas B, Do TVT, Yu Y, Ronish LA, McCullough H, Auchtung JM, Piepenbrink KH. Flagellin is essential for initial attachment to mucosal surfaces by Clostridioides difficile. Microbiol Spectr 2023; 11:e0212023. [PMID: 37823657 PMCID: PMC10714722 DOI: 10.1128/spectrum.02120-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2023] [Accepted: 09/04/2023] [Indexed: 10/13/2023] Open
Abstract
IMPORTANCE Clostridioides difficile is one of the leading causes of hospital-acquired infections worldwide and presents challenges in treatment due to recurrent gastrointestinal disease after treatment with antimicrobials. The mechanisms by which C. difficile colonizes the gut represent a key gap in knowledge, including its association with host cells and mucosa. Our results show the importance of flagellin for specific adhesion to mucosal hydrogels and can help to explain prior observations of adhesive defects in flagellin and pilin mutants.
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Affiliation(s)
- Ben Sidner
- Department of Food Science and Technology, University of Nebraska-Lincoln, Lincoln, Nebraska, USA
| | - Armando Lerma
- Department of Food Science and Technology, University of Nebraska-Lincoln, Lincoln, Nebraska, USA
| | - Baishakhi Biswas
- Department of Food Science and Technology, University of Nebraska-Lincoln, Lincoln, Nebraska, USA
| | - Thi Van Thanh Do
- Department of Food Science and Technology, University of Nebraska-Lincoln, Lincoln, Nebraska, USA
| | - Yafan Yu
- Department of Biochemistry, University of Nebraska-Lincoln, Lincoln, Nebraska, USA
| | - Leslie A. Ronish
- Department of Biochemistry, University of Nebraska-Lincoln, Lincoln, Nebraska, USA
| | - Hugh McCullough
- Department of Food Science and Technology, University of Nebraska-Lincoln, Lincoln, Nebraska, USA
- Nebraska Food for Health Center, University of Nebraska-Lincoln, Lincoln, Nebraska, USA
| | - Jennifer M. Auchtung
- Department of Food Science and Technology, University of Nebraska-Lincoln, Lincoln, Nebraska, USA
- Nebraska Food for Health Center, University of Nebraska-Lincoln, Lincoln, Nebraska, USA
| | - Kurt H. Piepenbrink
- Department of Food Science and Technology, University of Nebraska-Lincoln, Lincoln, Nebraska, USA
- Department of Biochemistry, University of Nebraska-Lincoln, Lincoln, Nebraska, USA
- Nebraska Food for Health Center, University of Nebraska-Lincoln, Lincoln, Nebraska, USA
- Department of Chemistry, University of Nebraska-Lincoln, Lincoln, Nebraska, USA
- Center for Integrated Biomolecular Communication, University of Nebraska-Lincoln, Lincoln, Nebraska, USA
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5
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Li S, Zhao W, Xia L, Kong L, Yang L. How Long Will It Take to Launch an Effective Helicobacter pylori Vaccine for Humans? Infect Drug Resist 2023; 16:3787-3805. [PMID: 37342435 PMCID: PMC10278649 DOI: 10.2147/idr.s412361] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Accepted: 06/02/2023] [Indexed: 06/22/2023] Open
Abstract
Helicobacter pylori infection often occurs in early childhood, and can last a lifetime if not treated with medication. H. pylori infection can also cause a variety of stomach diseases, which can only be treated with a combination of antibiotics. Combinations of antibiotics can cure H. pylori infection, but it is easy to relapse and develop drug resistance. Therefore, a vaccine is a promising strategy for prevention and therapy for the infection of H. pylori. After decades of research and development, there has been no appearance of any H. pylori vaccine reaching the market, unfortunately. This review summarizes the aspects of candidate antigens, immunoadjuvants, and delivery systems in the long journey of H. pylori vaccine research, and also introduces some clinical trials that have displayed encouraging or depressing results. Possible reasons for the inability of an H. pylori vaccine to be available over the counter are cautiously discussed and some propositions for the future of H. pylori vaccines are outlined.
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Affiliation(s)
- Songhui Li
- Jiangsu Key Laboratory of Bioactive Natural Product Research and State Key Laboratory of Natural Medicines, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing, 210009People’s Republic of China
| | - Wenfeng Zhao
- Department of Biochemistry, School of Life Science and Technology, China Pharmaceutical University, Nanjing, 210009People’s Republic of China
| | - Lei Xia
- Bloomage Biotechnology Corporation Limited, Jinan, People’s Republic of China
| | - Lingyi Kong
- Jiangsu Key Laboratory of Bioactive Natural Product Research and State Key Laboratory of Natural Medicines, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing, 210009People’s Republic of China
| | - Lei Yang
- Jiangsu Key Laboratory of Bioactive Natural Product Research and State Key Laboratory of Natural Medicines, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing, 210009People’s Republic of China
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6
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Sidner B, Lerma A, Biswas B, Ronish LA, McCullough H, Auchtung JM, Piepenbrink KH. Flagellin is essential for initial attachment to mucosal surfaces by Clostridioides difficile. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.19.541533. [PMID: 37292962 PMCID: PMC10245794 DOI: 10.1101/2023.05.19.541533] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Mucins are glycoproteins which can be found in host cell membranes and as a gelatinous surface formed from secreted mucins. Mucosal surfaces in mammals form a barrier to invasive microbes, particularly bacteria, but are a point of attachment for others. Clostridioides difficile is anaerobic bacterium which colonizes the mammalian GI tract and is a common cause of acute GI inflammation leading to a variety of negative outcomes. Although C. difficile toxicity stems from secreted toxins, colonization is a prerequisite for C. difficile disease. While C. difficile is known to associate with the mucus layer and underlying epithelium, the mechanisms underlying these interactions that facilitate colonization are less well-understood. To understand the molecular mechanisms by which C. difficile interacts with mucins, we used ex vivo mucosal surfaces to test the ability of C. difficile to bind to mucins from different mammalian tissues. We found significant differences in C. difficile adhesion based upon the source of mucins, with highest levels of binding observed to mucins purified from the human colonic adenocarcinoma line LS174T and lowest levels of binding to porcine gastric mucin. We also observed that defects in adhesion by mutants deficient in flagella, but not type IV pili. These results imply that interactions between host mucins and C. difficile flagella facilitate the initial host attachment of C. difficile to host cells and secreted mucus.
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7
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Bansil R, Constantino MA, Su-Arcaro C, Liao W, Shen Z, Fox JG. Motility of Different Gastric Helicobacter spp. Microorganisms 2023; 11:634. [PMID: 36985208 PMCID: PMC10058440 DOI: 10.3390/microorganisms11030634] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Revised: 02/24/2023] [Accepted: 02/28/2023] [Indexed: 03/06/2023] Open
Abstract
Helicobacter spp., including the well-known human gastric pathogen H. pylori, can cause gastric diseases in humans and other mammals. They are Gram-negative bacteria that colonize the gastric epithelium and use their multiple flagella to move across the protective gastric mucus layer. The flagella of different Helicobacter spp. vary in their location and number. This review focuses on the swimming characteristics of different species with different flagellar architectures and cell shapes. All Helicobacter spp. use a run-reverse-reorient mechanism to swim in aqueous solutions, as well as in gastric mucin. Comparisons of different strains and mutants of H. pylori varying in cell shape and the number of flagella show that their swimming speed increases with an increasing number of flagella and is somewhat enhanced with a helical cell body shape. The swimming mechanism of H. suis, which has bipolar flagella, is more complex than that of unipolar H. pylori. H. suis exhibits multiple modes of flagellar orientation while swimming. The pH-dependent viscosity and gelation of gastric mucin significantly impact the motility of Helicobacter spp. In the absence of urea, these bacteria do not swim in mucin gel at pH < 4, even though their flagellar bundle rotates.
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Affiliation(s)
- Rama Bansil
- Department of Physics, Boston University, Boston, MA 02215, USA
| | | | | | - Wentian Liao
- Department of Physics, Boston University, Boston, MA 02215, USA
| | - Zeli Shen
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02138, USA
| | - James G. Fox
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02138, USA
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Geng B, Liu S, Chen Y, Wu Y, Wang Y, Zhou X, Li H, Li M, Yang S. A plasmid-free Zymomonas mobilis mutant strain reducing reactive oxygen species for efficient bioethanol production using industrial effluent of xylose mother liquor. Front Bioeng Biotechnol 2022; 10:1110513. [PMID: 36619397 PMCID: PMC9816438 DOI: 10.3389/fbioe.2022.1110513] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Accepted: 12/12/2022] [Indexed: 12/24/2022] Open
Abstract
Genome minimization is an effective way for industrial chassis development. In this study, Zymomonas mobilis ZMNP, a plasmid-free mutant strain of Z. mobilis ZM4 with four native plasmids deleted, was constructed using native type I-F CRISPR-Cas system. Cell growth of ZMNP under different temperatures and industrial effluent of xylose mother liquor were examined to investigate the impact of native plasmid removal. Despite ZMNP grew similarly as ZM4 under different temperatures, ZMNP had better xylose mother liquor utilization than ZM4. In addition, genomic, transcriptomic, and proteomic analyses were applied to unravel the molecular changes between ZM4 and ZMNP. Whole-genome resequencing result indicated that an S267P mutation in the C-terminal of OxyR, a peroxide-sensing transcriptional regulator, probably alters the transcription initiation of antioxidant genes for stress responses. Transcriptomic and proteomic studies illustrated that the reason that ZMNP utilized the toxic xylose mother liquor better than ZM4 was probably due to the upregulation of genes in ZMNP involving in stress responses as well as cysteine biosynthesis to accelerate the intracellular ROS detoxification and nucleic acid damage repair. This was further confirmed by lower ROS levels in ZMNP compared to ZM4 in different media supplemented with furfural or ethanol. The upregulation of stress response genes due to the OxyR mutation to accelerate ROS detoxification and DNA/RNA repair not only illustrates the underlying mechanism of the robustness of ZMNP in the toxic xylose mother liquor, but also provides an idea for the rational design of synthetic inhibitor-tolerant microorganisms for economic lignocellulosic biochemical production.
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Affiliation(s)
- Binan Geng
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, School of Life Sciences, Hubei University, Wuhan, China
| | - Shuyi Liu
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, School of Life Sciences, Hubei University, Wuhan, China
| | - Yunhao Chen
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, School of Life Sciences, Hubei University, Wuhan, China
| | - Yalun Wu
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, School of Life Sciences, Hubei University, Wuhan, China
| | - Yi Wang
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, School of Life Sciences, Hubei University, Wuhan, China
| | - Xuan Zhou
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, School of Life Sciences, Hubei University, Wuhan, China
| | - Han Li
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, School of Life Sciences, Hubei University, Wuhan, China
| | - Mian Li
- Zhejiang Huakang Pharmaceutical Co., Ltd., Quzhou, Zhejiang, China
| | - Shihui Yang
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, School of Life Sciences, Hubei University, Wuhan, China,*Correspondence: Shihui Yang,
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9
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Fan D, Gong Y, Sun L, Zhang Y, Zhang J. Comparative transcriptome analysis to investigate the mechanism of anti-Helicobacter pylori activity of zinc. Microb Pathog 2022; 168:105611. [PMID: 35660509 DOI: 10.1016/j.micpath.2022.105611] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Revised: 03/22/2022] [Accepted: 05/28/2022] [Indexed: 10/18/2022]
Abstract
As a potential anti-Helicobacter pylori agent, zinc causes impairment of Helicobacter pylori growth, and this property of zinc is of broad interest to biological investigators. However, little is known about the molecular mechanisms by which zinc inhibits the growth of Helicobacter pylori. Here, an in vitro experiment revealed that zinc at specific concentrations inhibits Helicobacter pylori growth. Furthermore, an RNA sequencing-based investigation of the global regulatory response to zinc revealed that exposure to zinc altered the Helicobacter pylori transcriptional profile in numerous ways. A high concentration of zinc induced the upregulation of genes related to ribosomal subunit, ribosome biosynthesis, chaperone and adhesins. However, flagellar assembly genes and some type IV secretion system genes were repressed. In addition, the expression levels of some genes that encode transporters of metal ions and that play key roles in Helicobacter pylori pathogenicity were altered under conditions of zinc-induced stress. In summary, high concentrations of zinc initiated antimicrobial activity to Helicobacter pylori under the combined effect of multiple repressed or altered pathogenetic genes and metabolic pathways associated with bacteria growth. This result has significant implications for understanding not only the antimicrobial activity mechanism of zinc but also the role of zinc-mediated homeostasis in Helicobacter pylori.
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Affiliation(s)
- Dongjie Fan
- 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.
| | - Yanan Gong
- 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.
| | - Lu Sun
- 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.
| | - Yiyao Zhang
- Healthcare Security Bureau of Haidian District, Beijing, 100000, China.
| | - Jianzhong Zhang
- 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.
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10
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Comparing Diagnostic Accuracy of the fliD Gene and the glmM Gene in Helicobacter pylori. Jundishapur J Microbiol 2022. [DOI: 10.5812/jjm-121476] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Background: Helicobacter pylori (H. pylori) is one of the most common human bacterial infections, accounting for the infection of half of the world's population. The polymerase chain reaction (PCR) has high specificity and sensitivity in diagnosing this bacterial infection. Objectives: The present study aimed to compare the sensitivity and specificity of the fliD gene and the most widely used glmM gene in the PCR technique. Methods: The research population encompassed patients with indications for upper endoscopy. This cross-sectional study compared the sensitivity and specificity of a proposed gene (fliD) with the most widely used glmM gene to detect the H. pylori infection in tissue samples. Results: The participants encompassed ninety-nine participants aged above 18 years. Their median age was 45.92 ± 13.63 years. The most common complaints of the patients were epigastric pain and heartburn. Our described gold standard detected 61.6% and 38.4% as positive and negative, respectively. The sensitivity and specificity were 72.1% and 100.0% for the routine PCR (glmM gene) and 80.3% and 94.7% for the proposed PCR (fliD gene). Conclusions: Different genes have been used to detect H. pylori in PCR. The glmM gene is easily used to diagnose the H. pylori infection; however, according to the present findings, the fliD gene has higher sensitivity than the glmM gene. Accordingly, the former can be used as a screening gene for the H. pylori infection in the PCR technique.
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11
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Luo W, Wang Q, Zhang X, Gu D, Zhang W, Yuan C. Evaluation of the diagnostic value of FliD, a Helicobacter pylori flagellar protein. Jpn J Infect Dis 2022; 75:454-460. [PMID: 35354706 DOI: 10.7883/yoken.jjid.2021.795] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Novel immunodominant antigens are urgently required for diagnosis and vaccine of Helicobacter pylori(HP). FliD, an important colonization factor was cloned and expressed(rFliD) to evaluate the levels of specific-IgG, IgM and IgA antibodies in the serum of patients by ELISA. Rabbit anti-rFliD polyclonal antibody (pAb) was obtained by subcutaneous injections of rFliD. The rFliD-specific IFN-γ and IL-4 of peripheral blood mononuclear cells and CD4+ T cells from human were analyzed by enzyme-linked immunospot and flow cytometry. We found that the levels of rFliD-specific IgG, IgM and IgA were significantly higher in HP-infected-patients compared with healthy controls. IgG, IgM and IgA had diagnostic sensitivities of 92.6, 89.8 and 83.2%; specificities of 91.1, 88.7 and 64.6%; and areas under the receiver operating curves of 0.97, 0.96 and 0.92, respectively. Furthermore, rFliD-pAb was used in the immunohistochemical analysis of gastritis and gastric cancer tissues from patients infected with HP. The levels of rFliD-specific IFN-γ and IL-4 were significantly elevated in HP-infected patients and exhibited a T helper type 1-dominant subtype. These findings indicate that rFliD exhibits high validity as a biomarker in HP diagnosis and may also be a potent antigen for vaccine design due to its high cellular and humoral immune response.
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Affiliation(s)
- Wei Luo
- Department of Clinical Laboratory, Tianjin Medical University General Hospital, China
| | - Qian Wang
- Department of Pathology, Tianjin Haihe Hospital, Key Research Laboratory for Infectious Disease Prevention for State Administration of Traditional Chinese Medicine, China
| | - Xiaofang Zhang
- Department of Clinical Laboratory, Tianjin Medical University General Hospital, China
| | - Dongmei Gu
- Department of Clinical Laboratory, Tianjin Medical University General Hospital, China
| | - Weifeng Zhang
- Department of Clinical Laboratory, Tianjin Medical University General Hospital, China
| | - Chunhui Yuan
- Department of Laboratory Medicine, Wuhan Children's Hospital, Huazhong University of Science and Technology, China
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12
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Comparative Genomic Analysis of Statistically Significant Genomic Islands of Helicobacter pylori strains for better understanding the disease prognosis. Biosci Rep 2022; 42:230988. [PMID: 35258077 PMCID: PMC8935386 DOI: 10.1042/bsr20212084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 02/25/2022] [Accepted: 03/07/2022] [Indexed: 11/17/2022] Open
Abstract
Bacterial virulence factors are often located in their genomic islands (GIs). Helicobacter pylori, a highly diverse organism is reported to be associated with several gastrointestinal diseases like, gastritis, gastric cancer, peptic ulcer, duodenal ulcer etc. A novel similarity score-based comparative analysis with GIs of fifty H. pylori strains revealed clear idea of the various factors which promote disease progression. Two putative pathogenic GIs in some of the H. pylori strains were identified. One GI, having a putative labile enterotoxin and other dynamin-like proteins (DLPs), is predicted to increase the release of toxin by membrane vesicular formation. Another island contains a virulence-associated protein D (vapD) which is a component of a type-II toxin-antitoxin system (TAs), leads to enhance the severity of the H. pylori infection. Besides the well-known virulence factors like CagA, and VacA, several GIs have been identified which showed to have direct or indirect impact on H. pylori clinical outcomes. One such GI, containing lipopolysaccharide (LPS) biosynthesis genes was revealed to be directly connected with disease development by inhibiting the immune response. Another collagenase-containing GI worsens ulcers by slowing down the healing process. GI consisted of fliD operon was found to be connected to flagellar assembly and biofilm production. By residing in biofilms, bacteria can avoid antibiotic therapy, resulting in chronic infection. Along with well-studied CagA and VacA virulent genes, it is equally important to study these identified virulence factors for better understanding H. pylori induced disease prognosis.
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13
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Gollapalli P, Selvan G T, H M, Shetty P, Kumari N S. Genome-scale protein interaction network construction and topology analysis of functional hypothetical proteins in Helicobacter pylori divulges novel therapeutic targets. Microb Pathog 2021; 161:105293. [PMID: 34800634 DOI: 10.1016/j.micpath.2021.105293] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Revised: 08/25/2021] [Accepted: 11/12/2021] [Indexed: 02/07/2023]
Abstract
The emergence and spread of multi-drug resistance among Helicobacter pylori (H. pylori) strain raise more stakes for genetic research for discovering new drugs. The quantity of uncharacterized hypothetical proteins in the genome may provide an opportunity to explore their property and promulgation could act as a platform for designing the drugs, making them an intriguing genetic target. In this context, the present study aims to identify the key hypothetical proteins (HPs) and their biological regulatory processes in H. pylori. This investigation could provide a foundation to establish the molecular connectivity among the pathways using topological analysis of the protein interaction networks (PINs). The giant network derived from the extended network has 374 nodes connected via 925 edges. A total of 43 proteins with high betweenness centrality (BC), 54 proteins with a large degree, and 23 proteins with high BC and large degrees have been identified. HP 1479, HP 0056, HP 1481, HP 1021, HP 0043, HP 1019, gmd, flgA, HP 0472, HP 1486, HP 1478, and HP 1473 are categorized as hub nodes because they have a higher number of direct connections and are potentially more important in understanding HP's molecular interactions. The pathway enrichment analysis of the network clusters revealed significant involvement of HPs in pathways such as flagellar assembly, bacterial chemotaxis and lipopolysaccharide biosynthesis. This comprehensive computational study revealed HP's functional role and its druggability characteristics, which could be useful in the development of drugs to combat H. pylori infections.
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Affiliation(s)
- Pavan Gollapalli
- Central Research Laboratory, KS Hegde Medical Academy, Nitte (Deemed to be University), Mangalore, 575018, Karnataka, India.
| | - Tamizh Selvan G
- Central Research Laboratory, KS Hegde Medical Academy, Nitte (Deemed to be University), Mangalore, 575018, Karnataka, India
| | - Manjunatha H
- Department of Biochemistry, Jnana Bharathi Campus, Bangalore University, Bangalore, Karnataka, 560056, India
| | - Praveenkumar Shetty
- Central Research Laboratory, KS Hegde Medical Academy, Nitte (Deemed to be University), Mangalore, 575018, Karnataka, India
| | - Suchetha Kumari N
- Central Research Laboratory, KS Hegde Medical Academy, Nitte (Deemed to be University), Mangalore, 575018, Karnataka, India
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14
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Cho SY, Song WS, Yoon SI. Crystal structure of the flagellar cap protein FliD from Bdellovibrio bacteriovorus. Biochem Biophys Res Commun 2019; 519:652-658. [PMID: 31542231 DOI: 10.1016/j.bbrc.2019.09.024] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Accepted: 09/08/2019] [Indexed: 01/10/2023]
Abstract
Bdellovibrio bacteriovorus is a predator bacterial species of the Deltaproteobacteria class that requires flagellum-mediated motility to initiate the parasitization of other gram-negative bacteria. The flagellum is capped by FliD, which polymerizes flagellin into a flagellar filament. FliD has been reported to function as a species-specific oligomer, such as a tetramer, a pentamer, or a hexamer, in members of the Gammaproteobacteria class. However, the oligomeric state and structural features of FliD from bacterial species outside the Gammaproteobacteria class are unknown. Based on structural and biochemical analyses, we report here that B. bacteriovorus FliD (bbFliD) forms a tetramer. bbFliD tetramerizes in a circular head-to-tail arrangement by inserting the D2 domain of one subunit into the concave surface of the second subunit generated between the D2 and D3 domains as observed in Serratia marcescens FliD. However, bbFliD adopts a more compact and flat oligomeric structure, which exhibits a more extended tetramerization interface flanked by two additional surfaces due to different intersubunit and interdomain organizations as well as an elongated loop. In conclusion, FliD from B. bacteriovorus, which belongs to the Deltaproteobacteria class, also produces a tetramer similar to FliD from Gammaproteobacterial species but adopts a unique species-specific oligomeric structure.
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Affiliation(s)
- So Yeon Cho
- Division of Biomedical Convergence, College of Biomedical Science, Kangwon National University, Chuncheon, 24341, Republic of Korea
| | - Wan Seok Song
- Division of Biomedical Convergence, College of Biomedical Science, Kangwon National University, Chuncheon, 24341, Republic of Korea
| | - Sung-Il Yoon
- Division of Biomedical Convergence, College of Biomedical Science, Kangwon National University, Chuncheon, 24341, Republic of Korea.
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15
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Tsai J, Yeh Y, Lin L, Sun Y, Hsiao C. Crystal structure of the flagellin protein FlaG from Helicobacter pylori. J CHIN CHEM SOC-TAIP 2019. [DOI: 10.1002/jccs.201900162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Jia‐Yin Tsai
- Department of Life Science and Institute of Bioinformatics and Structural BiologyNational Tsing Hua University Hsinchu Taiwan
| | - Yi‐Hung Yeh
- Institute of Molecular BiologyAcademia Sinica Taipei Taiwan
| | - Lun‐Der Lin
- Department of Life Science and Institute of Bioinformatics and Structural BiologyNational Tsing Hua University Hsinchu Taiwan
| | - Yuh‐Ju Sun
- Department of Life Science and Institute of Bioinformatics and Structural BiologyNational Tsing Hua University Hsinchu Taiwan
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16
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Zhang K, Qin Z, Chang Y, Liu J, Malkowski MG, Shipa S, Li L, Qiu W, Zhang JR, Li C. Analysis of a flagellar filament cap mutant reveals that HtrA serine protease degrades unfolded flagellin protein in the periplasm of Borrelia burgdorferi. Mol Microbiol 2019; 111:1652-1670. [PMID: 30883947 DOI: 10.1111/mmi.14243] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/11/2019] [Indexed: 12/16/2022]
Abstract
Unlike external flagellated bacteria, spirochetes have periplasmic flagella (PF). Very little is known about how PF are assembled within the periplasm of spirochaetal cells. Herein, we report that FliD (BB0149), a flagellar cap protein (also named hook-associated protein 2), controls flagellin stability and flagellar filament assembly in the Lyme disease spirochete Borrelia burgdorferi. Deletion of fliD leads to non-motile mutant cells that are unable to assemble flagellar filaments and pentagon-shaped caps (10 nm in diameter, 12 nm in length). Interestingly, FlaB, a major flagellin protein of B. burgdorferi, is degraded in the fliD mutant but not in other flagella-deficient mutants (i.e., in the hook, rod, or MS-ring). Biochemical and genetic studies reveal that HtrA, a serine protease of B. burgdorferi, controls FlaB turnover. Specifically, HtrA degrades unfolded but not polymerized FlaB, and deletion of htrA increases the level of FlaB in the fliD mutant. Collectively, we propose that the flagellar cap protein FliD promotes flagellin polymerization and filament growth in the periplasm. Deletion of fliD abolishes this process, which leads to leakage of unfolded FlaB proteins into the periplasm where they are degraded by HtrA, a protease that prevents accumulation of toxic products in the periplasm.
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Affiliation(s)
- Kai Zhang
- Department of Oral and Craniofacial Molecular Biology, Philips Research Institute, Virginia Commonwealth University, Richmond, VI, 23298, USA
| | - Zhuan Qin
- Department of Microbial Pathogenesis & Microbial Sciences Institute, Yale University School of Medicine, New Haven, CT, 06516, USA
| | - Yunjie Chang
- Department of Microbial Pathogenesis & Microbial Sciences Institute, Yale University School of Medicine, New Haven, CT, 06516, USA
| | - Jun Liu
- Department of Microbial Pathogenesis & Microbial Sciences Institute, Yale University School of Medicine, New Haven, CT, 06516, USA
| | - Michael G Malkowski
- Department of Structural Biology, Jacobs School of Medicine and Biomedical Sciences, University of Buffalo, Buffalo, NY, 14203, USA
| | - Saimtun Shipa
- Department of Biological Sciences, City University of New York, New York, NY, 10021, USA
| | - Li Li
- Department of Biological Sciences, City University of New York, New York, NY, 10021, USA
| | - Weigang Qiu
- Department of Biological Sciences, City University of New York, New York, NY, 10021, USA
| | - Jing-Ren Zhang
- Center for Infectious Disease Research, School of Medicine, Tsinghua University, Beijing, 100084, China
| | - Chunhao Li
- Department of Oral and Craniofacial Molecular Biology, Philips Research Institute, Virginia Commonwealth University, Richmond, VI, 23298, USA
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17
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Cho SY, Song WS, Oh HB, Kim HU, Jung HS, Yoon SI. Structural analysis of the flagellar capping protein FliD from Helicobacter pylori. Biochem Biophys Res Commun 2019; 514:98-104. [PMID: 31023530 DOI: 10.1016/j.bbrc.2019.04.065] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2019] [Accepted: 04/09/2019] [Indexed: 01/17/2023]
Abstract
Helicobacter pylori is a pathogenic flagellated bacterium that infects the gastroduodenal mucosa and causes peptic ulcers in humans. FliD caps the distal end of the flagellar filament and is essential in filament growth. Moreover, FliD has been studied to diagnose and prevent H. pylori infection. Here, we report structure-based molecular studies of H. pylori FliD (hpFliD). A crystal structure of hpFliD at 2.6 Å resolution presents a four-domain (D2-D5) structure, where the D3 domain forms a central platform surrounded by the other three domains (D2, D4, and D5). hpFliD domains D2 and D3 structurally resemble those of FliD orthologs, whereas the D4 and D5 domains are exclusive to hpFliD. Moreover, our ELISA analysis using anti-H. pylori antibodies demonstrated that the hpFliD-specific D4 and D5 domains are highly antigenic compared to the D2 and D3 domains. Collectively, our structural and serological analyses underscore the structural role of hpFliD domains and provide a molecular basis for vaccine and diagnosis development.
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Affiliation(s)
- So Yeon Cho
- Division of Biomedical Convergence, College of Biomedical Science, Kangwon National University, Chuncheon, 24341, Republic of Korea
| | - Wan Seok Song
- Division of Biomedical Convergence, College of Biomedical Science, Kangwon National University, Chuncheon, 24341, Republic of Korea
| | - Han-Byeol Oh
- Division of Biomedical Convergence, College of Biomedical Science, Kangwon National University, Chuncheon, 24341, Republic of Korea
| | - Han-Ul Kim
- Department of Biochemistry, College of Natural Sciences, Kangwon National University, Chuncheon, 24341, Republic of Korea
| | - Hyun Suk Jung
- Department of Biochemistry, College of Natural Sciences, Kangwon National University, Chuncheon, 24341, Republic of Korea
| | - Sung-Il Yoon
- Division of Biomedical Convergence, College of Biomedical Science, Kangwon National University, Chuncheon, 24341, Republic of Korea; Institute of Bioscience and Biotechnology, Kangwon National University, Chuncheon, 24341, Republic of Korea.
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18
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Kryshtafovych A, Albrecht R, Baslé A, Bule P, Caputo AT, Carvalho AL, Chao KL, Diskin R, Fidelis K, Fontes CMGA, Fredslund F, Gilbert HJ, Goulding CW, Hartmann MD, Hayes CS, Herzberg O, Hill JC, Joachimiak A, Kohring GW, Koning RI, Lo Leggio L, Mangiagalli M, Michalska K, Moult J, Najmudin S, Nardini M, Nardone V, Ndeh D, Nguyen TH, Pintacuda G, Postel S, van Raaij MJ, Roversi P, Shimon A, Singh AK, Sundberg EJ, Tars K, Zitzmann N, Schwede T. Target highlights from the first post-PSI CASP experiment (CASP12, May-August 2016). Proteins 2018; 86 Suppl 1:27-50. [PMID: 28960539 PMCID: PMC5820184 DOI: 10.1002/prot.25392] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Revised: 09/19/2017] [Accepted: 09/25/2017] [Indexed: 12/27/2022]
Abstract
The functional and biological significance of the selected CASP12 targets are described by the authors of the structures. The crystallographers discuss the most interesting structural features of the target proteins and assess whether these features were correctly reproduced in the predictions submitted to the CASP12 experiment.
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Affiliation(s)
- Andriy Kryshtafovych
- Genome Center, University of California, Davis, 451 Health Sciences Drive, Davis, California, 95616
| | - Reinhard Albrecht
- Department of Protein Evolution, Max Planck Institute for Developmental Biology, Tübingen, 72076, Germany
| | - Arnaud Baslé
- Institute for Cell and Molecular Biosciences, University of Newcastle, Newcastle upon Tyne NE2 4HH, United Kingdom
| | - Pedro Bule
- CIISA - Faculdade de Medicina Veterinária, Universidade de Lisboa, Avenida da Universidade Técnica, 1300-477, Portugal, Lisboa
| | - Alessandro T Caputo
- Oxford Glycobiology Institute, Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, England, United Kingdom
| | - Ana Luisa Carvalho
- UCIBIO, REQUIMTE, Departamento de Química, Faculdade de Cien⁁cias e Tecnologia, Universidade Nova de Lisboa, Caparica, 2829-516, Portugal
| | - Kinlin L Chao
- Institute for Bioscience and Biotechnology Research, University of Maryland, Rockville, Maryland, 20850
| | - Ron Diskin
- Department of Structural Biology, Weizmann Institute of Science, Rehovot, Israel
| | - Krzysztof Fidelis
- Genome Center, University of California, Davis, 451 Health Sciences Drive, Davis, California, 95616
| | - Carlos M G A Fontes
- CIISA - Faculdade de Medicina Veterinária, Universidade de Lisboa, Avenida da Universidade Técnica, 1300-477, Portugal, Lisboa
| | - Folmer Fredslund
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen Ø, Denmark
| | - Harry J Gilbert
- Institute for Cell and Molecular Biosciences, University of Newcastle, Newcastle upon Tyne NE2 4HH, United Kingdom
| | - Celia W Goulding
- Department of Molecular Biology and Biochemistry/Pharmaceutical Sciences, University of California Irvine, Irvine, California, 92697
| | - Marcus D Hartmann
- Department of Protein Evolution, Max Planck Institute for Developmental Biology, Tübingen, 72076, Germany
| | - Christopher S Hayes
- Department of Molecular, Cellular and Developmental Biology/Biomolecular Science and Engineering Program, University of California, Santa Barbara, Santa Barbara, California, 93106
| | - Osnat Herzberg
- Institute for Bioscience and Biotechnology Research, University of Maryland, Rockville, Maryland, 20850
- Department of Chemistry and Biochemistry, University of Maryland, College Park, Maryland, 20742
| | - Johan C Hill
- Oxford Glycobiology Institute, Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, England, United Kingdom
| | - Andrzej Joachimiak
- Argonne National Laboratory, Midwest Center for Structural Genomics/Structural Biology Center, Biosciences Division, Argonne, Illinois, 60439
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, Illinois, 60637
| | - Gert-Wieland Kohring
- Microbiology, Saarland University, Campus Building A1.5, Saarbrücken, Saarland, D-66123, Germany
| | - Roman I Koning
- Netherlands Centre for Electron Nanoscopy, Institute of Biology Leiden, Leiden University, 2333, CC Leiden, The Netherlands
- Department of Molecular Cell Biology, Leiden University Medical Center, 2300 RC, Leiden, The Netherlands
| | - Leila Lo Leggio
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen Ø, Denmark
| | - Marco Mangiagalli
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Milano, 20126, Italy
| | - Karolina Michalska
- Argonne National Laboratory, Midwest Center for Structural Genomics/Structural Biology Center, Biosciences Division, Argonne, Illinois, 60439
| | - John Moult
- Department of Cell Biology and Molecular genetics, University of Maryland, 9600 Gudelsky Drive, Institute for Bioscience and Biotechnology Research, Rockville, Maryland, 20850
| | - Shabir Najmudin
- CIISA - Faculdade de Medicina Veterinária, Universidade de Lisboa, Avenida da Universidade Técnica, 1300-477, Portugal, Lisboa
| | - Marco Nardini
- Department of Biosciences, University of Milano, Milano, 20133, Italy
| | - Valentina Nardone
- Department of Biosciences, University of Milano, Milano, 20133, Italy
| | - Didier Ndeh
- Institute for Cell and Molecular Biosciences, University of Newcastle, Newcastle upon Tyne NE2 4HH, United Kingdom
| | - Thanh-Hong Nguyen
- Department of Macromolecular Structures, Centro Nacional de Biotecnologia (CSIC), calle Darwin 3, Madrid, 28049, Spain
| | - Guido Pintacuda
- Université de Lyon, Centre de RMN à Très Hauts Champs, Institut des Sciences Analytiques (UMR 5280 - CNRS, ENS Lyon, UCB Lyon 1), Villeurbanne, 69100, France
| | - Sandra Postel
- University of Maryland School of Medicine, Institute of Human Virology, Baltimore, Maryland, 21201
| | - Mark J van Raaij
- Department of Macromolecular Structures, Centro Nacional de Biotecnologia (CSIC), calle Darwin 3, Madrid, 28049, Spain
| | - Pietro Roversi
- Oxford Glycobiology Institute, Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, England, United Kingdom
- Leicester Institute of Structural and Chemical Biology, Department of Molecular and Cell Biology, University of Leicester, Henry Wellcome Building, University Road, Leicester, LE1 7RN, UK
| | - Amir Shimon
- Department of Structural Biology, Weizmann Institute of Science, Rehovot, Israel
| | - Abhimanyu K Singh
- School of Biosciences, University of Kent, Canterbury, Kent, CT2 7NJ, United Kingdom
| | - Eric J Sundberg
- Department of Medicine and Department of Microbiology and Immunology, University of Maryland School of Medicine, Institute of Human Virology, Baltimore, Maryland, 21201
| | - Kaspars Tars
- Latvian Biomedical Research and Study Center, Rātsupītes 1, Riga, LV1067, Latvia
- Faculty of Biology, Department of Molecular Biology, University of Latvia, Jelgavas 1, Riga, LV-1004, Latvia
| | - Nicole Zitzmann
- Oxford Glycobiology Institute, Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, England, United Kingdom
| | - Torsten Schwede
- Biozentrum/SIB Swiss Institute of Bioinformatics, Klingelbergstrasse 50, Basel, 4056, Switzerland
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19
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Li H, Zhang B, Hu X, Dong Y, Fan Q, Guo F, Ren X, Zhou H, Tian W, Zhao Y. Serum Helicobacter pylori FliD antibody and the risk of gastric cancer. Oncotarget 2017; 7:22397-408. [PMID: 26968951 PMCID: PMC5008368 DOI: 10.18632/oncotarget.7981] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2015] [Accepted: 02/23/2016] [Indexed: 02/06/2023] Open
Abstract
FliD and CagA are important virulence factors of H. pylori. We aimed to evaluate the screening values of FliD and CagA for gastric cancer (GC). Serum samples were obtained from 232 cases and 266 controls in a case-control study. Unconditional multivariate logistic regression with odds ratios (ORs) and 95% confidence intervals (CIs) was used to analyze the relationships between FliD, CagA and GC. The sensitivities, specificities and receiver operating characteristic (ROC) curves were calculated. Finally, the combined screening values of FliD, FlaA, NapA and CagA were assessed based on discriminant analysis. In all subjects, the associations of FliD and CagA with GC were evident with ORs (95% CIs) of 7.6 (4.7-12.3) and 2.5 (1.6-3.8), respectively (*p<0.001). The areas under ROC curves (AUCs) for FliD and CagA were 0.800 and 0.653, respectively. The AUC for the combination of FliD, FlaA and NapA was 0.915, which represented an increase of 0.115 over that of FliD alone (*p<0.001). These findings indicate that the FliD antibody is associated with GC and could exhibit high validity as a biomarker in screening for GC patients. The combination of FliD, FlaA and NapA improved the screening validity.
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Affiliation(s)
- Hailin Li
- Department of Epidemiology, College of Public Health, Harbin Medical University, Harbin, Heilongjiang Province, P. R. China
| | - Bing Zhang
- Department of Epidemiology, College of Public Health, Harbin Medical University, Harbin, Heilongjiang Province, P. R. China
| | - Xiaomeng Hu
- Department of Epidemiology, College of Public Health, Harbin Medical University, Harbin, Heilongjiang Province, P. R. China
| | - Yingzi Dong
- Department of Epidemiology, College of Public Health, Harbin Medical University, Harbin, Heilongjiang Province, P. R. China
| | - Qing Fan
- Xiangfang Center for Disease Control and Prevention, Harbin, Heilongjiang Province, P. R. China
| | - Fang Guo
- Department of Epidemiology, College of Public Health, Harbin Medical University, Harbin, Heilongjiang Province, P. R. China
| | - Xiyun Ren
- Department of Epidemiology, College of Public Health, Harbin Medical University, Harbin, Heilongjiang Province, P. R. China
| | - Haibo Zhou
- Department of Epidemiology, College of Public Health, Harbin Medical University, Harbin, Heilongjiang Province, P. R. China
| | - Wenjing Tian
- Department of Epidemiology, College of Public Health, Harbin Medical University, Harbin, Heilongjiang Province, P. R. China
| | - Yashuang Zhao
- Department of Epidemiology, College of Public Health, Harbin Medical University, Harbin, Heilongjiang Province, P. R. China
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20
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Cho SY, Song WS, Hong HJ, Lee GS, Kang SG, Ko HJ, Kim PH, Yoon SI. Tetrameric structure of the flagellar cap protein FliD from Serratia marcescens. Biochem Biophys Res Commun 2017; 489:63-69. [PMID: 28527888 DOI: 10.1016/j.bbrc.2017.05.093] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2017] [Accepted: 05/16/2017] [Indexed: 11/30/2022]
Abstract
Bacterial motility is provided by the flagellum. FliD is located at the distal end of the flagellum and plays a key role in the insertion of each flagellin protein at the growing tip of the flagellar filament. Because FliD functions as an oligomer, the determination of the oligomeric state of FliD is critical to understanding the molecular mechanism of FliD-mediated flagellar growth. FliD has been shown to adopt a pentameric or a hexameric structure depending on the bacterial species. Here, we report another distinct oligomeric form of FliD based on structural and biochemical studies. The crystal structures of the D2 and D3 domains of Serratia marcescens FliD (smFliD) were determined in two crystal forms and together revealed that smFliD assembles into a tetrameric architecture that resembles a four-pointed star plate. smFliD tetramerization was also confirmed in solution by cross-linking experiments. Although smFliD oligomerizes in a head-to-tail orientation using a common primary binding interface between the D2 and D3' domains (the prime denotes the second subunit in the oligomer) similarly to other FliD orthologs, the smFliD tetramer diverges to present a unique secondary D2-D2' binding interface. Our structure-based comparative analysis of FliD suggests that bacteria have developed diverse species-specific oligomeric forms of FliD that range from tetramers to hexamers for flagellar growth.
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Affiliation(s)
- So Yeon Cho
- Division of Biomedical Convergence, College of Biomedical Science, Kangwon National University, Chuncheon 24341, Republic of Korea
| | - Wan Seok Song
- Division of Biomedical Convergence, College of Biomedical Science, Kangwon National University, Chuncheon 24341, Republic of Korea
| | - Ho Jeong Hong
- Division of Biomedical Convergence, College of Biomedical Science, Kangwon National University, Chuncheon 24341, Republic of Korea
| | - Geun-Shik Lee
- College of Veterinary Medicine, Kangwon National University, Chuncheon 24341, Republic of Korea
| | - Seung Goo Kang
- Division of Biomedical Convergence, College of Biomedical Science, Kangwon National University, Chuncheon 24341, Republic of Korea
| | - Hyun-Jeong Ko
- Laboratory of Microbiology and Immunology, College of Pharmacy, Kangwon National University, Chuncheon 24341, Republic of Korea
| | - Pyeung-Hyeun Kim
- Department of Molecular Bioscience, School of Biomedical Science, Kangwon National University, Chuncheon 24341, Republic of Korea
| | - Sung-Il Yoon
- Division of Biomedical Convergence, College of Biomedical Science, Kangwon National University, Chuncheon 24341, Republic of Korea; Institute of Bioscience and Biotechnology, Kangwon National University, Chuncheon 24341, Republic of Korea.
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21
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Gu H. Role of Flagella in the Pathogenesis of Helicobacter pylori. Curr Microbiol 2017; 74:863-869. [PMID: 28444418 PMCID: PMC5447363 DOI: 10.1007/s00284-017-1256-4] [Citation(s) in RCA: 101] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Accepted: 04/18/2017] [Indexed: 12/15/2022]
Abstract
This review aimed to investigate the role of Helicobacter pylori flagella on the pathogenicity of this bacterium in humans. Helicobacter pylori is a flagellated pathogen that colonizes the human gastroduodenal mucosa and produces inflammation, and is responsible for gastrointestinal disease. Its pathogenesis is attributed to colonization and virulence factors. The primary function of H. pylori flagella is to provide motility. We believe that H. pylori flagella play an important role in the colonization of the gastrointestinal mucosa. Therefore, we reviewed previous studies on flagellar morphology and motility in order to explore the relationship between H. pylori flagella and pathogenicity. Further investigation is required to confirm the association between flagella and pathogenicity in H. pylori.
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Affiliation(s)
- Haiying Gu
- Medical School, Ningbo University, Ningbo, 315211, China.
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Song WS, Cho SY, Hong HJ, Park SC, Yoon SI. Self-Oligomerizing Structure of the Flagellar Cap Protein FliD and Its Implication in Filament Assembly. J Mol Biol 2017; 429:847-857. [PMID: 28179186 DOI: 10.1016/j.jmb.2017.02.001] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Revised: 02/01/2017] [Accepted: 02/01/2017] [Indexed: 12/30/2022]
Abstract
FliD is a self-oligomerizing structural protein that caps the growing end of the bacterial flagellar filament. FliD also plays a key role in the flagellar system by continuously adding a new flagellin protein to the tip of the filament. To structurally characterize FliD oligomerization and to provide a FliD-mediated flagellin polymerization mechanism, we have determined the crystal structures of FliD proteins from Escherichia coli and Salmonella enterica serovar Typhimurium (ecFliD and stFliD, respectively). ecFliD consists of three domains (D1, D2, and D3) and forms a hexamer plate of the D2 and D3 domains that resembles a six-pointed star with legs consisting of the D1 domain. In contrast, the D2 and D3 domains of stFliD assemble into a pentamer as a five-pointed star plate. Despite their distinct oligomeric states, ecFliD and stFliD engage a common molecular surface for oligomerization. FliD also features interdomain and intersubunit flexibility, suggesting that FliD reorganizes its domains and adjacent subunits depending on the FliD binding partner. The similarity of the FliD shape to flagellin and the structural dynamics of FliD led us to propose a FliD-catalyzed filament elongation mechanism. In this model, FliD occupies a position in place of a nascent flagellin until the flagellin reaches the growing end of the filament, and then, FliD moves aside to repeat the positional replacement.
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Affiliation(s)
- Wan Seok Song
- Division of Biomedical Convergence, College of Biomedical Science, Kangwon National University, Chuncheon 24341, Republic of Korea
| | - So Yeon Cho
- Division of Biomedical Convergence, College of Biomedical Science, Kangwon National University, Chuncheon 24341, Republic of Korea
| | - Ho Jeong Hong
- Division of Biomedical Convergence, College of Biomedical Science, Kangwon National University, Chuncheon 24341, Republic of Korea
| | - Sun Cheol Park
- Division of Biomedical Convergence, College of Biomedical Science, Kangwon National University, Chuncheon 24341, Republic of Korea
| | - Sung-Il Yoon
- Division of Biomedical Convergence, College of Biomedical Science, Kangwon National University, Chuncheon 24341, Republic of Korea; Institute of Bioscience and Biotechnology, Kangwon National University, Chuncheon 24341, Republic of Korea.
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Ratthawongjirakul P, Thongkerd V, Chaicumpa W. The impacts of a fliD mutation on the biofilm formation of Helicobacter pylori. Asian Pac J Trop Biomed 2016. [DOI: 10.1016/j.apjtb.2016.10.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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24
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Postel S, Deredge D, Bonsor DA, Yu X, Diederichs K, Helmsing S, Vromen A, Friedler A, Hust M, Egelman EH, Beckett D, Wintrode PL, Sundberg EJ. Bacterial flagellar capping proteins adopt diverse oligomeric states. eLife 2016; 5. [PMID: 27664419 PMCID: PMC5072837 DOI: 10.7554/elife.18857] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Accepted: 09/23/2016] [Indexed: 11/13/2022] Open
Abstract
Flagella are crucial for bacterial motility and pathogenesis. The flagellar capping protein (FliD) regulates filament assembly by chaperoning and sorting flagellin (FliC) proteins after they traverse the hollow filament and exit the growing flagellum tip. In the absence of FliD, flagella are not formed, resulting in impaired motility and infectivity. Here, we report the 2.2 Å resolution X-ray crystal structure of FliD from Pseudomonas aeruginosa, the first high-resolution structure of any FliD protein from any bacterium. Using this evidence in combination with a multitude of biophysical and functional analyses, we find that Pseudomonas FliD exhibits unexpected structural similarity to other flagellar proteins at the domain level, adopts a unique hexameric oligomeric state, and depends on flexible determinants for oligomerization. Considering that the flagellin filaments on which FliD oligomers are affixed vary in protofilament number between bacteria, our results suggest that FliD oligomer stoichiometries vary across bacteria to complement their filament assemblies. DOI:http://dx.doi.org/10.7554/eLife.18857.001 Many bacteria, including several that cause diseases in people, have long whip-like appendages called flagella that extend well beyond their cell walls. Flagella can rotate and propel the bacteria through liquids, such as water or blood, and they are constructed primarily from thousands of copies of a single protein called flagellin. When flagella are built, the flagellin proteins are placed in their proper positions by another protein called FliD, several copies of which form a cap on the end of flagella. Without FliD, bacteria cannot properly assemble flagella and, thus, can no longer swim; this also hinders their ability to cause disease. Determining the three-dimensional structure of a protein, down to the level of its individual atoms, can provide unique insights into how the protein operates. However, no one had resolved the structure of a FliD protein from any bacterium to this level of detail before. Now, Postel et al. report the high-resolution structure of a large fragment of FliD from the bacterium Pseudomonas aeruginosa. The structure reveals that parts of this FliD protein are shaped like parts of other proteins from which flagella are constructed, including the flagellin protein that FliD places into position. Some parts of the FliD protein are also very flexible and these parts of the protein are responsible for holding numerous FliD proteins together as a cap. Finally, Postel et al. saw that six copies of FliD bind to one another to form a protein complex on the end of flagella. This last finding was particularly unexpected since it was thought that all FliD proteins formed five-membered cap complexes, an assumption that was based largely on studies of FliD from another bacterium called Salmonella. The current structure covers about half of the FliD protein, and so the next challenge is to determine the structure of the full-length protein. An improved understanding of the structure of FliD may, in future, help researchers to design drugs that stop bacteria from building flagella and, therefore, from swimming and causing disease. DOI:http://dx.doi.org/10.7554/eLife.18857.002
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Affiliation(s)
- Sandra Postel
- Institute of Human Virology, University of Maryland School of Medicine, Baltimore, United States
| | - Daniel Deredge
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, Baltimore, United States
| | - Daniel A Bonsor
- Institute of Human Virology, University of Maryland School of Medicine, Baltimore, United States
| | - Xiong Yu
- Department of Biochemistry and Molecular Genetics, University of Virginia, Charlottesville, United States
| | - Kay Diederichs
- Department of Biology, University of Konstanz, Konstanz, Germany
| | - Saskia Helmsing
- Department of Biotechnology, Institute of Biochemistry, Biotechnology and Bioinformatics, Technische Universität Braunschweig, Braunschweig, Germany
| | - Aviv Vromen
- Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Assaf Friedler
- Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Michael Hust
- Department of Biotechnology, Institute of Biochemistry, Biotechnology and Bioinformatics, Technische Universität Braunschweig, Braunschweig, Germany
| | - Edward H Egelman
- Department of Biochemistry and Molecular Genetics, University of Virginia, Charlottesville, United States
| | - Dorothy Beckett
- Department of Chemistry and Biochemistry, University of Maryland College Park, Baltimore, United States
| | - Patrick L Wintrode
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, Baltimore, United States
| | - Eric J Sundberg
- Institute of Human Virology, University of Maryland School of Medicine, Baltimore, United States.,Department of Medicine, University of Maryland School of Medicine, Baltimore, United States.,Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, United States
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Comparative Genomic and Phenotypic Characterization of Pathogenic and Non-Pathogenic Strains of Xanthomonas arboricola Reveals Insights into the Infection Process of Bacterial Spot Disease of Stone Fruits. PLoS One 2016; 11:e0161977. [PMID: 27571391 PMCID: PMC5003339 DOI: 10.1371/journal.pone.0161977] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Accepted: 08/15/2016] [Indexed: 02/07/2023] Open
Abstract
Xanthomonas arboricola pv. pruni is the causal agent of bacterial spot disease of stone fruits, a quarantinable pathogen in several areas worldwide, including the European Union. In order to develop efficient control methods for this disease, it is necessary to improve the understanding of the key determinants associated with host restriction, colonization and the development of pathogenesis. After an initial characterization, by multilocus sequence analysis, of 15 strains of X. arboricola isolated from Prunus, one strain did not group into the pathovar pruni or into other pathovars of this species and therefore it was identified and defined as a X. arboricola pv. pruni look-a-like. This non-pathogenic strain and two typical strains of X. arboricola pv. pruni were selected for a whole genome and phenotype comparative analysis in features associated with the pathogenesis process in Xanthomonas. Comparative analysis among these bacterial strains isolated from Prunus spp. and the inclusion of 15 publicly available genome sequences from other pathogenic and non-pathogenic strains of X. arboricola revealed variations in the phenotype associated with variations in the profiles of TonB-dependent transporters, sensors of the two-component regulatory system, methyl accepting chemotaxis proteins, components of the flagella and the type IV pilus, as well as in the repertoire of cell-wall degrading enzymes and the components of the type III secretion system and related effectors. These variations provide a global overview of those mechanisms that could be associated with the development of bacterial spot disease. Additionally, it pointed out some features that might influence the host specificity and the variable virulence observed in X. arboricola.
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Kao CY, Sheu BS, Wu JJ. Helicobacter pylori infection: An overview of bacterial virulence factors and pathogenesis. Biomed J 2016; 39:14-23. [PMID: 27105595 PMCID: PMC6138426 DOI: 10.1016/j.bj.2015.06.002] [Citation(s) in RCA: 263] [Impact Index Per Article: 32.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2015] [Accepted: 06/08/2015] [Indexed: 12/16/2022] Open
Abstract
Helicobacter pylori pathogenesis and disease outcomes are mediated by a complex interplay between bacterial virulence factors, host, and environmental factors. After H. pylori enters the host stomach, four steps are critical for bacteria to establish successful colonization, persistent infection, and disease pathogenesis: (1) Survival in the acidic stomach; (2) movement toward epithelium cells by flagella-mediated motility; (3) attachment to host cells by adhesins/receptors interaction; (4) causing tissue damage by toxin release. Over the past 20 years, the understanding of H. pylori pathogenesis has been improved by studies focusing on the host and bacterial factors through epidemiology researches and molecular mechanism investigations. These include studies identifying the roles of novel virulence factors and their association with different disease outcomes, especially the bacterial adhesins, cag pathogenicity island, and vacuolating cytotoxin. Recently, the development of large-scale screening methods, including proteomic, and transcriptomic tools, has been used to determine the complex gene regulatory networks in H. pylori. In addition, a more available complete genomic database of H. pylori strains isolated from patients with different gastrointestinal diseases worldwide is helpful to characterize this bacterium. This review highlights the key findings of H. pylori virulence factors reported over the past 20 years.
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Affiliation(s)
- Cheng-Yen Kao
- Department of Medical Laboratory Science and Biotechnology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Bor-Shyang Sheu
- Department of Internal Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Jiunn-Jong Wu
- Department of Medical Laboratory Science and Biotechnology, College of Medicine, National Cheng Kung University, Tainan, Taiwan; Center of Infectious Disease and Signaling Research, National Cheng Kung University, Tainan, Taiwan; Department of Biotechnology and Laboratory Science in Medicine, School of Biomedical Science and Engineering, National Yang-Ming University, Taipei, Taiwan.
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Flagellar Cap Protein FliD Mediates Adherence of Atypical Enteropathogenic Escherichia coli to Enterocyte Microvilli. Infect Immun 2016; 84:1112-1122. [PMID: 26831466 DOI: 10.1128/iai.01001-15] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Accepted: 01/27/2016] [Indexed: 11/20/2022] Open
Abstract
The expression of flagella correlates with different aspects of bacterial pathogenicity, ranging from adherence to host cells to activation of inflammatory responses by the innate immune system. In the present study, we investigated the role of flagella in the adherence of an atypical enteropathogenic Escherichia coli (aEPEC) strain (serotype O51:H40) to human enterocytes. Accordingly, isogenic mutants deficient in flagellin (FliC), the flagellar structural subunit; the flagellar cap protein (FliD); or the MotAB proteins, involved in the control of flagellar motion, were generated and tested for binding to differentiated Caco-2 cells. Binding of the aEPEC strain to enterocytes was significantly impaired in strains with the fliCa nd fliD genes deleted, both of which could not form flagella on the bacterial surface. A nonmotile but flagellated MotAB mutant also showed impaired adhesion to Caco-2 cells. In accordance with these observations, adhesion of a EPEC strain 1711-4 to Caco-2 cells was drastically reduced after the treatment of Caco-2 cells with purified FliD. In addition, incubation of a EPEC bacteria with specific anti-FliD serum impaired binding to Caco-2 cells. Finally, incubation of Caco-2 cells with purified FliD, followed by immunolabeling, showed that the protein was specifically bound to the microvillus tips of differentiated Caco-2 cells. The a EPEC FliD or anti-FliD serum also reduced the adherence of prototype typical enteropathogenic, enterohemorrhagic, and enterotoxigenic E. coli strains to Caco-2 cells. In conclusion, our findings further strengthened the role of flagella in the adherence of a EPEC to human enterocytes and disclosed the relevant structural and functional involvement of FliD in the adhesion process.
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28
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Yeh H, Hiett KL, Line JE, Jagne JF, Lauer DC. Seroprevalence in Chickens against
Campylobacter jejuni
Flagellar Capping Protein (FliD) in Selected Areas of the United States. Zoonoses Public Health 2015; 63:265-70. [DOI: 10.1111/zph.12237] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2015] [Indexed: 01/27/2023]
Affiliation(s)
- H.‐Y. Yeh
- United States Department of Agriculture Agricultural Research Service U.S. National Poultry Research Center Poultry Microbiological Safety and Processing Research Unit Athens GA USA
| | - K. L. Hiett
- United States Department of Agriculture Agricultural Research Service U.S. National Poultry Research Center Poultry Microbiological Safety and Processing Research Unit Athens GA USA
| | - J. E. Line
- United States Department of Agriculture Agricultural Research Service U.S. National Poultry Research Center Poultry Microbiological Safety and Processing Research Unit Athens GA USA
| | - J. F. Jagne
- Animal Health Diagnostic Center Cornell University Ithaca NY USA
| | - D. C. Lauer
- Minnesota Poultry Testing Laboratory University of Minnesota Willmar MN USA
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29
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Cao J, Lai Q, Yuan J, Shao Z. Genomic and metabolic analysis of fluoranthene degradation pathway in Celeribacter indicus P73T. Sci Rep 2015; 5:7741. [PMID: 25582347 PMCID: PMC4291564 DOI: 10.1038/srep07741] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2014] [Accepted: 11/20/2014] [Indexed: 01/22/2023] Open
Abstract
Celeribacter indicus P73(T), isolated from deep-sea sediment from the Indian Ocean, is capable of degrading a wide range of polycyclic aromatic hydrocarbons (PAHs) and is the first fluoranthene-degrading bacterium within the family Rhodobacteraceae. Here, the complete genome sequence of strain P73(T) is presented and analyzed. Besides a 4.5-Mb circular chromosome, strain P73(T) carries five plasmids, and encodes 4827 predicted protein-coding sequences. One hundred and thirty-eight genes, including 14 dioxygenase genes, were predicted to be involved in the degradation of aromatic compounds, and most of these genes are clustered in four regions. P73_0346 is the first fluoranthene 7,8-dioxygenase to be discovered and the first fluoranthene dioxygenase within the toluene/biphenyl family. The degradative genes in regions B and D in P73(T) are absent in Celeribacter baekdonensis B30, which cannot degrade PAHs. Four intermediate metabolites [acenaphthylene-1(2H)-one, acenaphthenequinone, 1,2-dihydroxyacenaphthylene, and 1,8-naphthalic anhydride] of fluoranthene degradation by strain P73(T) were detected as the main intermediates, indicating that the degradation of fluoranthene in P73(T) was initiated by dioxygenation at the C-7,8 positions. Based on the genomic and metabolitic results, we propose a C-7,8 dioxygenation pathway in which fluoranthene is mineralized to TCA cycle intermediates.
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Affiliation(s)
- Junwei Cao
- State Key Laboratory Breeding Base of Marine Genetic Resources; Key Laboratory of Marine Genetic Resources, The Third Institute of State Oceanic Administration; Key Laboratory of Marine Genetic Resources of Fujian Province; Collaborative Innovation Center of Deep Sea Biology; Collaborative Innovation Center for Exploitation and Utilization of Marine Biological Resources, Xiamen 361005, China
- School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin 150090, China
| | - Qiliang Lai
- State Key Laboratory Breeding Base of Marine Genetic Resources; Key Laboratory of Marine Genetic Resources, The Third Institute of State Oceanic Administration; Key Laboratory of Marine Genetic Resources of Fujian Province; Collaborative Innovation Center of Deep Sea Biology; Collaborative Innovation Center for Exploitation and Utilization of Marine Biological Resources, Xiamen 361005, China
| | - Jun Yuan
- State Key Laboratory Breeding Base of Marine Genetic Resources; Key Laboratory of Marine Genetic Resources, The Third Institute of State Oceanic Administration; Key Laboratory of Marine Genetic Resources of Fujian Province; Collaborative Innovation Center of Deep Sea Biology; Collaborative Innovation Center for Exploitation and Utilization of Marine Biological Resources, Xiamen 361005, China
| | - Zongze Shao
- State Key Laboratory Breeding Base of Marine Genetic Resources; Key Laboratory of Marine Genetic Resources, The Third Institute of State Oceanic Administration; Key Laboratory of Marine Genetic Resources of Fujian Province; Collaborative Innovation Center of Deep Sea Biology; Collaborative Innovation Center for Exploitation and Utilization of Marine Biological Resources, Xiamen 361005, China
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Kao CY, Sheu BS, Wu JJ. CsrA regulates Helicobacter pylori J99 motility and adhesion by controlling flagella formation. Helicobacter 2014; 19:443-54. [PMID: 25109343 DOI: 10.1111/hel.12148] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
BACKGROUND Motility mediated by the flagella of Helicobacter pylori has been shown to be required for normal colonization and is thought to be important for the bacteria to move toward the gastric mucus in niches adjacent to the epithelium. Barnard et al. showed that CsrA appears to be necessary for full motility and the ability to infect mice, but its mechanism of regulation is still unclear. METHODS Motility and cell adhesion ability were determined in wild-type, csrA mutant, and revertant J99 strains. The bacterial shape and flagellar structure were evaluated by transmission electron microscopy. The expression of two major flagellins, flaA/flaB, and the alternative sigma factor rpoN (σ(54)) were determined by real-time quantitative RT-PCR and Western blot. RESULTS The csrA mutant showed loss of motility and lower adhesion ability compared with the wild-type and revertant J99 strains. The csrA mutant was not flagellated. Transcription of flaA and flaB mRNA decreased to only 40% and 16%, respectively, in the csrA mutant compared with the wild-type J99 (p = .006 and <.0001, respectively), and Western blot analysis showed dramatically reduced FlaA/FlaB proteins in a csrA mutant. The disruption of csrA also decreased expression of rpoN to 48% in the csrA mutant, but the degradation rate of rpoN mRNA was not changed. CONCLUSION These results suggest that CsrA regulates H. pylori J99 flagella formation and thereby affects bacterial motility.
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Affiliation(s)
- Cheng-Yen Kao
- Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan
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Yeh HY, Hiett KL, Line JE, Seal BS. Characterization and antigenicity of recombinant Campylobacter jejuni flagellar capping protein FliD. J Med Microbiol 2014; 63:602-609. [DOI: 10.1099/jmm.0.060095-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Campylobacter jejuni, a flagellated, spiral-rod, Gram-negative bacterium, is the leading pathogen of human acute bacterial gastroenteritis worldwide, and chickens are regarded as a major reservoir of this micro-organism. Bacterial flagella, composed of more than 35 proteins, play important roles in colonization and adhesion to the mucosal surface of chicken caeca. In this study, the flagellar capping protein, FliD, encoded by the fliD gene, from the Campylobacter jenuni D1-39 isolate was expressed and characterized, and its antigenicity determined. The fliD gene comprised 1929 nt, potentially encoding a 642 aa peptide with a calculated molecular mass of 69.6 kDa. This gene was PCR amplified and overexpressed in Escherichia coli. The recombinant FliD protein was purified by cobalt-chelating affinity chromatography and confirmed by nucleotide sequencing of the expression plasmid, SDS-PAGE analysis, His tag detection and matrix-assisted laser desorption/ionization time of flight mass spectrometry. The immunoblot data showed that the purified recombinant FliD protein reacted strongly to sera from broiler chickens older than 4 weeks, indicating that anti-FliD antibody may be prevalent in the poultry population. These results provide a rationale for further evaluation of the FliD protein as a vaccine candidate for broiler chickens to improve food safety for poultry.
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Affiliation(s)
- Hung-Yueh Yeh
- US Department of Agriculture, Agricultural Research Service, Richard B. Russell Agricultural Research Center, Poultry Microbiological Safety Research Unit, 950 College Station Road, Athens, GA 30605-2720, USA
| | - Kelli L. Hiett
- US Department of Agriculture, Agricultural Research Service, Richard B. Russell Agricultural Research Center, Poultry Microbiological Safety Research Unit, 950 College Station Road, Athens, GA 30605-2720, USA
| | - John E. Line
- US Department of Agriculture, Agricultural Research Service, Richard B. Russell Agricultural Research Center, Poultry Microbiological Safety Research Unit, 950 College Station Road, Athens, GA 30605-2720, USA
| | - Bruce S. Seal
- US Department of Agriculture, Agricultural Research Service, Richard B. Russell Agricultural Research Center, Poultry Microbiological Safety Research Unit, 950 College Station Road, Athens, GA 30605-2720, USA
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Pereira LE, Tsang J, Mrázek J, Hoover TR. The zinc-ribbon domain of Helicobacter pylori HP0958: requirement for RpoN accumulation and possible roles of homologs in other bacteria. MICROBIAL INFORMATICS AND EXPERIMENTATION 2014; 1:1-10. [PMID: 22408721 PMCID: PMC3372290 DOI: 10.1186/2042-5783-1-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Background Helicobacter pylori HP0958 protein (FlgZ) prevents the rapid turnover of RpoN (σ54), a transcription factor required for expression of several flagellar genes in H. pylori. FlgZ possesses a zinc-ribbon domain (DUF164) that contains two conserved CXXC motifs which coordinate a zinc ion and is thought to interact with nucleic acids or proteins. Two conserved cysteine residues in FlgZ (Cys-202 and Cys-223) were replaced with serine to assess their significance in FlgZ function. After confirming the importance of the CXXC motifs in the DUF164 domain of FlgZ, the distribution of DUF164 proteins and RpoN homologs in other bacteria was examined to determine if a correlation existed for the concurrence of the two proteins. Results Levels of RpoN were greatly reduced in H. pylori strains that expressed the FlgZC202S or FlgZC223S variants. The FlgZC202S variant, but not the FlgZC223S variant, accumulated at levels similar to the wild-type protein. DUF164 proteins are not universally distributed and appear to be absent in several major bacterial taxa, including Cyanobacteria as well as Alpha-, Beta- and Gammaproteobacteria. With the exception of the Actinobacteria, members of which generally lack RpoN, genes encoding DUF164 proteins and RpoN are frequently found in the same genome. Interestingly, many of the DUF164 proteins in Actinobacteria and Bacteroidetes lack most or even all of the conserved cysteine residues. Conclusions These findings suggest the importance of the zinc-ribbon domain of FlgZ in protecting RpoN from turnover. Since many bacteria that possess a DUF164 protein also contain RpoN, DUF164 proteins may have roles in RpoN protection or function in other bacteria.
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Affiliation(s)
- Lara E Pereira
- Emory Vaccine Center, 954 Gatewood Road, Emory University, Atlanta, GA 30329, USA
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33
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Helicobacter pylori FliD protein is a highly sensitive and specific marker for serologic diagnosis of H. pylori infection. Int J Med Microbiol 2013; 303:618-23. [DOI: 10.1016/j.ijmm.2013.08.005] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2013] [Revised: 08/07/2013] [Accepted: 08/18/2013] [Indexed: 02/06/2023] Open
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The role of the bacterial flagellum in adhesion and virulence. BIOLOGY 2013; 2:1242-67. [PMID: 24833223 PMCID: PMC4009794 DOI: 10.3390/biology2041242] [Citation(s) in RCA: 343] [Impact Index Per Article: 31.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/30/2013] [Revised: 09/27/2013] [Accepted: 09/30/2013] [Indexed: 12/11/2022]
Abstract
The bacterial flagellum is a complex apparatus assembled of more than 20 different proteins. The flagellar basal body traverses the cell wall, whereas the curved hook connects the basal body to the whip-like flagellar filament that protrudes several µm from the bacterial cell. The flagellum has traditionally been regarded only as a motility organelle, but more recently it has become evident that flagella have a number of other biological functions. The major subunit, flagellin or FliC, of the flagellum plays a well-documented role in innate immunity and as a dominant antigen of the adaptive immune response. Importantly, flagella have also been reported to function as adhesins. Whole flagella have been indicated as significant in bacterial adhesion to and invasion into host cells. In various pathogens, e.g., Escherichia coli, Pseudomonas aeruginosa and Clostridium difficile, flagellin and/or the distally located flagellar cap protein have been reported to function as adhesins. Recently, FliC of Shiga-toxigenic E. coli was shown to be involved in cellular invasion via lipid rafts. Here, we examine the latest or most important findings regarding flagellar adhesive and invasive properties, especially focusing on the flagellum as a potential virulence factor.
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Sun Y, Liu S, Li W, Shan Y, Li X, Lu X, Li Y, Guo Q, Zhou Y, Jia J. Proteomic analysis of the function of sigma factor σ54 in Helicobacter pylori survival with nutrition deficiency stress in vitro. PLoS One 2013; 8:e72920. [PMID: 24015282 PMCID: PMC3755968 DOI: 10.1371/journal.pone.0072920] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2013] [Accepted: 07/15/2013] [Indexed: 12/13/2022] Open
Abstract
H. pylori can survive under a nutrition-deficient environment. During infection and transmission, H. pylori is confronted with nutrient limitation and the bacterium requires rapid alteration in gene expression for survival under stress conditions. However, the mechanism underlining this regulation remains unknown. A previous study showed that σ54 is an important regulation factor for H. pylori survival in the nutrition-deficient environment. Our results show that the expression of σ54 (rpoN) is significantly induced in the stationary phase (nutrition deficiency) and the rpoN mutant showed a significantly lower viability than wild-type H. pylori in the late stationary phase. Thus, σ54 is involved in H. pylori survival during nutrient limitation. We used comparative proteomics to analyze the protein differentiation between wild-type and rpoN mutant during the stationary phase. With depleted nutrients, σ54 can slow the process of proliferation by negatively regulating genes involved in energy metabolism and biosynthesis and enhance stress-resistant ability by positively regulating genes involved in protein fate and redox reaction. Especially, NapA positively regulated by σ54 plays an important function in H. pylori survival both in the stationary phase and in water, and the latter situation would be beneficial for bacterial in vitro transmission. Our investigations give new light on the adaptive regulation of H. pylori under stress conditions.
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Affiliation(s)
- Yundong Sun
- Department of Microbiology, Key Laboratory for Experimental Teratology of Chinese Ministry of Education, School of Medicine, Shandong University, Jinan, Shandong, China
- * E-mail: (JJ); (YS)
| | - Shuang Liu
- Department of Microbiology, Key Laboratory for Experimental Teratology of Chinese Ministry of Education, School of Medicine, Shandong University, Jinan, Shandong, China
- Clinical Laboratory, First Affiliated Hospital of Dalian Medical University, Dalian, Liaoning, China
| | - Wen Li
- Department of Microbiology, Key Laboratory for Experimental Teratology of Chinese Ministry of Education, School of Medicine, Shandong University, Jinan, Shandong, China
| | - Yuqun Shan
- Department of Microbiology, Key Laboratory for Experimental Teratology of Chinese Ministry of Education, School of Medicine, Shandong University, Jinan, Shandong, China
| | - Xinpeng Li
- Department of Microbiology, Key Laboratory for Experimental Teratology of Chinese Ministry of Education, School of Medicine, Shandong University, Jinan, Shandong, China
- Disease Control and Prevention of Shandong Province, Jinan, China
| | - Xingxiao Lu
- Department of Microbiology, Key Laboratory for Experimental Teratology of Chinese Ministry of Education, School of Medicine, Shandong University, Jinan, Shandong, China
| | - Yan Li
- School of Control Science and Engineering, Shandong University, Jinan, China
| | - Qing Guo
- Department of Microbiology, Key Laboratory for Experimental Teratology of Chinese Ministry of Education, School of Medicine, Shandong University, Jinan, Shandong, China
| | - Yabin Zhou
- Department of Microbiology, Key Laboratory for Experimental Teratology of Chinese Ministry of Education, School of Medicine, Shandong University, Jinan, Shandong, China
| | - Jihui Jia
- Department of Microbiology, Key Laboratory for Experimental Teratology of Chinese Ministry of Education, School of Medicine, Shandong University, Jinan, Shandong, China
- * E-mail: (JJ); (YS)
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Kao CY, Sheu BS, Sheu SM, Yang HB, Chang WL, Cheng HC, Wu JJ. Higher motility enhances bacterial density and inflammatory response in dyspeptic patients infected with Helicobacter pylori. Helicobacter 2012; 17:411-6. [PMID: 23066970 DOI: 10.1111/j.1523-5378.2012.00974.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
BACKGROUND Motility mediated by the flagella of Helicobacter pylori is important for the cells to move toward the gastric mucus in niches adjacent to the epithelium; then, H. pylori uses the adhesin SabA to interact with sialyl-Le(x) on inflammatory host cells for persistent infection. Here, we reveal the clinical association of bacterial motility, SabA expression, and pathological outcomes. METHODS Ninety-six clinical isolates were screened for bacterial motility, and the expression of SabA of each isolate was confirmed by Western blotting. H. pylori-infected patients were assessed for their bacterial density, sialyl-Le(x) expression, inflammatory scores, and clinical diseases. RESULTS The mean diameter in the motility assay was 17 mm, and eight (8.3%) of the strains had impaired motility, with a diameter <5 mm. H. pylori density in cardia, the acute inflammatory score in the body locus, and the prevalence rate of gastric atrophy were increased in patients infected with higher-motility strains (p = .023, <.001, or <.001, respectively). The total inflammatory scores (both acute and chronic) and bacterial density dramatically increased in patients expressing the sialyl-Le(x) antigen and infected with higher-motility, SabA-positive H. pylori (p = .016, .01, or .005, respectively). CONCLUSION These results suggest that the higher motility of H. pylori enhances pathological outcomes, and the SabA-sialyl-Le(x) interaction has a synergistic effect on virulence of the higher-motility strains.
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Affiliation(s)
- Cheng-Yen Kao
- Institute of Basic Medical Sciences, College of Medicine, National Cheng-Kung University, Tainan, Taiwan
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Shao C, Zhou Y, Sun Y, Wang H, Qu W, Yu H, Chen C, Jia J. Analysis of aztreonam-inducing proteome changes in nondividing filamentous Helicobacter pylori. Curr Microbiol 2012; 65:108-15. [PMID: 22538471 DOI: 10.1007/s00284-012-0132-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2012] [Accepted: 04/11/2012] [Indexed: 11/26/2022]
Abstract
When stressed, bacteria can enter various nondividing states. In the present study, nondividing filamentous form in Helicobacter pylori was induced by a β-lactam antibiotic, aztreonam. In order to find possible cell division checkpoints in H. pylori, 2-DE was used to compare the proteomic profile of nondividing filamentous H. pylori with its spiral form. In total, 21 proteins involved in various cellular processes showed differential expression. One protein induced by aztreonam was a cell division inhibitor (minD), related to cell division. We then constructed the deletion mutant of minD in H. pylori 26695. Scanning electron microscope observation showed that the deletion of this protein provoked some bacteria to change into a short rod-shape and the viability of the mutant is lower than that of the wild type. Moreover, sequence comparison showed that minD of H. pylori and that of Escherichia coli share 50 % amino acid identity. This suggested that this protein possibly plays the similar part in H. pylori as in E. coli.
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Affiliation(s)
- Chunhong Shao
- Clinical Laboratory, Provincial Hospital Affiliated to Shandong University, Jinan, People's Republic of China.
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38
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Lertsethtakarn P, Ottemann KM, Hendrixson DR. Motility and chemotaxis in Campylobacter and Helicobacter . Annu Rev Microbiol 2012; 65:389-410. [PMID: 21939377 DOI: 10.1146/annurev-micro-090110-102908] [Citation(s) in RCA: 218] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Flagellar motility of Campylobacter jejuni and Helicobacter pylori influences host colonization by promoting migration through viscous milieus such as gastrointestinal mucus. This review explores mechanisms C. jejuni and H. pylori employ to control flagellar biosynthesis and chemotactic responses. These microbes tightly control the activities of σ(54) and σ(28) to mediate ordered flagellar gene expression. In addition to phase-variable and posttranslational mechanisms, flagellar biosynthesis is regulated spatially and numerically so that only a certain number of organelles are placed at polar sites. To mediate chemotaxis, C. jejuni and H. pylori combine basic chemotaxis signal transduction components with several accessory proteins. H. pylori is unusual in that it lacks a methylation-based adaptation system and produces multiple CheV coupling proteins. Chemoreceptors in these bacteria contain nonconserved ligand binding domains, with several chemoreceptors matched to environmental signals. Together, these mechanisms allow for swimming motility that is essential for colonization.
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Affiliation(s)
- Paphavee Lertsethtakarn
- Department of Microbiology and Environmental Toxicology, University of California, Santa Cruz, Santa Cruz, California 95064, USA
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Sonnenschein EC, Gärdes A, Seebah S, Torres-Monroy I, Grossart HP, Ullrich MS. Development of a genetic system for Marinobacter adhaerens HP15 involved in marine aggregate formation by interacting with diatom cells. J Microbiol Methods 2011; 87:176-83. [PMID: 21880271 DOI: 10.1016/j.mimet.2011.08.008] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2011] [Revised: 08/12/2011] [Accepted: 08/12/2011] [Indexed: 10/17/2022]
Abstract
Diatom aggregation is substantial for organic carbon flux from the photic zone to deeper waters. Many heterotrophic bacteria ubiquitously found in diverse marine environments interact with marine algae and thus impact organic matter and energy cycling in the ocean. In particular, Marinobacter adhaerens HP15 induces aggregate formation while interacting with the diatom, Thalassiosira weissflogii. To study this effect at the molecular level, a genetic tool system was developed for strain HP15. The antibiotic susceptibility spectrum of this organism was determined and electroporation and conjugation protocols were established. Among various plasmids of different incompatibility groups, only two were shown to replicate in M. adhaerens. 1.4×10(-3) transconjugants per recipient were obtained for a broad-host-range vector. Electroporation efficiency corresponded to 1.1×10(5)CFU per μg of DNA. Transposon and gene-specific mutageneses were conducted for flagellum biosynthetic genes. Mutant phenotypes were confirmed by swimming assay and microscopy. Successful expression of two reporter genes in strain HP15 revealed useful tools for gene expression analyses, which will allow studying diverse bacteria-algae interactions at the molecular level and hence to gain a mechanistic understanding of micro-scale processes underlying ocean basin-scale processes. This study is the first report for the genetic manipulation of a Marinobacter species which specifically interacts with marine diatoms and serves as model to additionally analyze various previously reported Marinobacter-algae interactions in depth.
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Affiliation(s)
- Eva C Sonnenschein
- Jacobs University Bremen, School of Engineering and Science, 28759 Bremen, Germany
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Genetic and molecular characterization of flagellar assembly in Shewanella oneidensis. PLoS One 2011; 6:e21479. [PMID: 21731763 PMCID: PMC3120886 DOI: 10.1371/journal.pone.0021479] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2011] [Accepted: 06/02/2011] [Indexed: 01/17/2023] Open
Abstract
Shewanella oneidensis is a highly motile organism by virtue of a polar flagellum. Unlike most flagellated bacteria, it contains only one major chromosome segment encoding the components of the flagellum with the exception of the motor proteins. In this region, three genes encode flagellinsaccording to the original genome annotation. However, we find that only flaA and flaB encode functional filament subunits. Although these two genesare under the control of different promoters, they are actively transcribed and subsequently translated, producing a considerable number of flagellin proteins. Additionally, both flagellins are able to interact with their chaperon FliS and are subjected to feedback regulation. Furthermore, FlaA and FlaB are glycosylated by a pathwayinvolving a major glycosylating enzyme,PseB, in spite of the lack of the majority of theconsensus glycosylation sites. In conclusion, flagellar assembly in S. oneidensis has novel features despite the conservation of homologous genes across taxa.
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Gilbreath JJ, Cody WL, Merrell DS, Hendrixson DR. Change is good: variations in common biological mechanisms in the epsilonproteobacterial genera Campylobacter and Helicobacter. Microbiol Mol Biol Rev 2011; 75:84-132. [PMID: 21372321 PMCID: PMC3063351 DOI: 10.1128/mmbr.00035-10] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Microbial evolution and subsequent species diversification enable bacterial organisms to perform common biological processes by a variety of means. The epsilonproteobacteria are a diverse class of prokaryotes that thrive in diverse habitats. Many of these environmental niches are labeled as extreme, whereas other niches include various sites within human, animal, and insect hosts. Some epsilonproteobacteria, such as Campylobacter jejuni and Helicobacter pylori, are common pathogens of humans that inhabit specific regions of the gastrointestinal tract. As such, the biological processes of pathogenic Campylobacter and Helicobacter spp. are often modeled after those of common enteric pathogens such as Salmonella spp. and Escherichia coli. While many exquisite biological mechanisms involving biochemical processes, genetic regulatory pathways, and pathogenesis of disease have been elucidated from studies of Salmonella spp. and E. coli, these paradigms often do not apply to the same processes in the epsilonproteobacteria. Instead, these bacteria often display extensive variation in common biological mechanisms relative to those of other prototypical bacteria. In this review, five biological processes of commonly studied model bacterial species are compared to those of the epsilonproteobacteria C. jejuni and H. pylori. Distinct differences in the processes of flagellar biosynthesis, DNA uptake and recombination, iron homeostasis, interaction with epithelial cells, and protein glycosylation are highlighted. Collectively, these studies support a broader view of the vast repertoire of biological mechanisms employed by bacteria and suggest that future studies of the epsilonproteobacteria will continue to provide novel and interesting information regarding prokaryotic cellular biology.
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Affiliation(s)
- Jeremy J. Gilbreath
- Department of Microbiology and Immunology, Uniformed Services University of the Health Sciences, Bethesda, Maryland 20814, Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| | - William L. Cody
- Department of Microbiology and Immunology, Uniformed Services University of the Health Sciences, Bethesda, Maryland 20814, Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| | - D. Scott Merrell
- Department of Microbiology and Immunology, Uniformed Services University of the Health Sciences, Bethesda, Maryland 20814, Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| | - David R. Hendrixson
- Department of Microbiology and Immunology, Uniformed Services University of the Health Sciences, Bethesda, Maryland 20814, Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, Texas 75390
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42
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Helicobacter pylori and gastric cancer: factors that modulate disease risk. Clin Microbiol Rev 2010; 23:713-39. [PMID: 20930071 DOI: 10.1128/cmr.00011-10] [Citation(s) in RCA: 919] [Impact Index Per Article: 65.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Helicobacter pylori is a gastric pathogen that colonizes approximately 50% of the world's population. Infection with H. pylori causes chronic inflammation and significantly increases the risk of developing duodenal and gastric ulcer disease and gastric cancer. Infection with H. pylori is the strongest known risk factor for gastric cancer, which is the second leading cause of cancer-related deaths worldwide. Once H. pylori colonizes the gastric environment, it persists for the lifetime of the host, suggesting that the host immune response is ineffective in clearing this bacterium. In this review, we discuss the host immune response and examine other host factors that increase the pathogenic potential of this bacterium, including host polymorphisms, alterations to the apical-junctional complex, and the effects of environmental factors. In addition to host effects and responses, H. pylori strains are genetically diverse. We discuss the main virulence determinants in H. pylori strains and the correlation between these and the diverse clinical outcomes following H. pylori infection. Since H. pylori inhibits the gastric epithelium of half of the world, it is crucial that we continue to gain understanding of host and microbial factors that increase the risk of developing more severe clinical outcomes.
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Detailed in vivo analysis of the role of Helicobacter pylori Fur in colonization and disease. Infect Immun 2010; 78:3073-82. [PMID: 20421381 DOI: 10.1128/iai.00190-10] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Helicobacter pylori persistently colonizes the harsh and dynamic environment of the stomach in over one-half of the world's population and has been identified as a causal agent in a spectrum of pathologies that range from gastritis to invasive adenocarcinoma. The ferric uptake regulator (Fur) is one of the few regulatory proteins that has been identified in H. pylori. Fur regulates genes important for acid acclimation and oxidative stress and has been shown to be important for colonization of H. pylori in both murine and Mongolian gerbil models of infection. To more thoroughly define the role of Fur in vivo, we conducted an extensive temporal analysis of the location of, competitive ability of, and resultant pathology induced by a Deltafur strain in the Mongolian gerbil model of infection and compared the results to results for its wild-type parent. We found that at the earliest time points postinfection, significantly more Deltafur bacteria than wild-type bacteria were recovered. However, this trend was reversed by day 3, when there was significantly increased recovery of the wild-type strain. The increased recovery of the Deltafur strain at 1 day postinfection reflected increased recovery from both the corpus and the antrum of the stomach. When the wild-type strain was allowed to colonize first, the Deltafur strain was unable to compete for colonization at any time postinfection. However, when the Deltafur strain was allowed to colonize first, the wild type efficiently outcompeted the Deltafur strain only at early times postinfection. Finally, we demonstrated that there was a delay in the development and severity of inflammation and pathology of the Deltafur strain in the gastric mucosa even after comparable levels of colonization occurred. Together, these data indicate that H. pylori Fur is most important at early stages of infection and illustrate the importance of the ability of H. pylori to adapt to its constantly fluctuating environment when it is establishing infection, inflammation, and disease.
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Abstract
Cronobacter spp. are opportunistic food-borne pathogens that can cause severe and sometimes lethal infections in neonates. In some outbreaks, the sources of infection were traced to contaminated powdered infant formula (PIF) or contaminated utensils used for PIF reconstitution. In this study, we investigated biofilm formation in Cronobacter sakazakii strain ES5. To investigate the genetic basis of biofilm formation in Cronobacter on abiotic surfaces, we screened a library of random transposon mutants of strain ES5 for reduced biofilm formation using a polystyrene microtiter assay. Genetic characterization of the mutants led to identification of genes that are associated with cellulose biosynthesis and flagellar structure and biosynthesis and genes involved in basic cellular processes and virulence, as well as several genes whose functions are currently unknown. In two of the mutants, hypothetical proteins ESA_00281 and ESA_00282 had a strong impact on flow cell biofilm architecture, and their contribution to biofilm formation was confirmed by genetic complementation. In addition, adhesion of selected biofilm formation mutants to Caco-2 intestinal epithelial cells was investigated. Our findings suggest that flagella and hypothetical proteins ESA_00281 and ESA_00282, but not cellulose, contribute to adhesion of Cronobacter to this biotic surface.
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Sheu BS, Yang HB, Yeh YC, Wu JJ. Helicobacter pylori colonization of the human gastric epithelium: a bug's first step is a novel target for us. J Gastroenterol Hepatol 2010; 25:26-32. [PMID: 20136973 DOI: 10.1111/j.1440-1746.2009.06141.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
After Helicobacter pylori enters the stomach, three steps are vital for infection: (i) establishing colonization; (ii) evading host immunity; and (iii) invading gastric mucosa; the last step is what is associated with diverse outcomes. Urease activity and motility mediated by the flagella of H. pylori are important in harboring colonies beneath the gastric mucus in niches adjacent to the epithelium. Several putative adhesins attach the organism to the gastric epithelium and prompt the succeeding processes for evading host immunity and invading the mucosa. Successful colonization is thus the leading and critical step. From another point of view, this can be a novel target to control this common and important infection. This review summarizes the putative adhesins that influence the evasion of host immunity, and how these could determine different clinico-pathologic outcomes. The putative adhesins include the interplay between bacterial and host Lewis antigens (type I: Le(a) and Le(b); type II: Le(x) and Le(y)), the dominant pathway between BabA and Le(b), the SabA adhesin binding to sialylated Le(x) that is upregulated in inflamed gastric tissue or those with weak-Le(b), the CagL apparatus to adapt with the alpha5beta1 integrin to mediate a type IV secretory system for CagA translocation into the epithelium; and other outer membrane proteins as HopZ, AlpA/AlpB, or OipA, without known corresponding receptors. This review implicates the adhesins vital for bugs that could be alternatively provided as novel targets for us to overcome the colonization.
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Affiliation(s)
- Bor-Shyang Sheu
- Department of Internal Medicine and Graduate Institute of Clinical Medicine, National Cheng Kung University Medical Center, Tainan, Taiwan.
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Duckworth MJ, Okoli AS, Mendz GL. Novel Helicobacter pylori therapeutic targets: the unusual suspects. Expert Rev Anti Infect Ther 2009; 7:835-67. [PMID: 19735225 DOI: 10.1586/eri.09.61] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Understanding the current status of the discovery and development of anti-Helicobacter therapies requires an overview of the searches for therapeutic targets performed to date. A summary is given of the very substantial body of work conducted in the quest to find Helicobacter pylori genes that could be suitable candidates for therapeutic intervention. The products of most of these genes perform metabolic functions, and others have roles in growth, cell motility and colonization. The genes identified as potential targets have been organized into three categories according to their degree of characterization. A short description and evaluation is provided of the main candidates in each category. Investigations of potential therapeutic targets have generated a wealth of information about the physiology and genetics of H. pylori, and its interactions with the host, but have yielded little by way of new therapies.
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Affiliation(s)
- Megan J Duckworth
- School of Medicine, Sydney, The University of Notre Dame Australia, 160 Oxford Street, Darlinghurst, NSW 2010, Australia.
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Qu W, Zhou Y, Shao C, Sun Y, Zhang Q, Chen C, Jia J. Helicobacter pylori proteins response to nitric oxide stress. J Microbiol 2009; 47:486-93. [PMID: 19763424 DOI: 10.1007/s12275-008-0266-0] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2008] [Accepted: 04/01/2009] [Indexed: 12/12/2022]
Abstract
Helicobacter pylori is a highly pathogenic microorganism with various strategies to evade human immune responses. Nitric oxide (NO) and reactive nitrogen species (RNS) generated via nitric oxide synthase pathway are important effectors during the innate immune response. However, the mechanisms of H. pylori to survive the nitrosative stress are not clear. Here the proteomic approach has been used to define the adaptive response of H. pylori to nitrosative stress. Proteomic analysis showed that 38 protein spots were regulated by NO donor, sodium nitroprusside (SNP). These proteins were involved in protein processing, anti-oxidation, general stress response, and virulence, as well as some unknown functions. Particularly, some of them were participated in iron metabolism, potentially under the control of ferric uptake regulator (Fur). Real time PCR revealed that fur was induced under nitrosative stress, consistent with our deduction. One stress-related protein up-regulated under nitrosative conditions was thioredoxin reductase (TrxR). Inactivation of fur or trxR can lead to increased susceptivity to nitrosative stress respectively. These studies described the adaptive response of H. pylori to nitric oxide stress, and analyzed the relevant role of Fur regulon and TrxR in nitrosative stress management.
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Affiliation(s)
- Wei Qu
- Department of Microbiology and Key Lab for Experimental Teratology of Chinese Ministry of Education, School of Medicine, Shandong University, Jinan 250012, P. R. China
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Chiu HC, Lin TL, Yang JC, Wang JT. Synergistic effect of imp/ostA and msbA in hydrophobic drug resistance of Helicobacter pylori. BMC Microbiol 2009; 9:136. [PMID: 19594901 PMCID: PMC2719649 DOI: 10.1186/1471-2180-9-136] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2009] [Accepted: 07/13/2009] [Indexed: 11/22/2022] Open
Abstract
Background Contamination of endoscopy equipment by Helicobacter pylori (H. pylori) frequently occurs after endoscopic examination of H. pylori-infected patients. In the hospital, manual pre-cleaning and soaking in glutaraldehyde is an important process to disinfect endoscopes. However, this might not be sufficient to remove H. pylori completely, and some glutaraldehyde-resistant bacteria might survive and be passed to the next patient undergoing endoscopic examination through unidentified mechanisms. We identified an Imp/OstA protein associated with glutaraldehyde resistance in a clinical strain, NTUH-C1, from our previous study. To better understand and manage the problem of glutaraldehyde resistance, we further investigated its mechanism. Results The minimal inhibitory concentrations (MICs) of glutaraldehyde andexpression of imp/ostA RNA in 11 clinical isolates from the National Taiwan University Hospital were determined. After glutaraldehyde treatment, RNA expression in the strains with the MICs of 4–10 μg/ml was higher than that in strains with the MICs of 1–3 μg/ml. We examined the full-genome expression of strain NTUH-S1 after glutaraldehyde treatment using a microarray and found that 40 genes were upregulated and 31 genes were downregulated. Among the upregulated genes, imp/ostA and msbA, two putative lipopolysaccharide biogenesis genes, were selected for further characterization. The sensitivity to glutaraldehyde or hydrophobic drugs increased in both of imp/ostA and msbA single mutants. The imp/ostA and msbA double mutant was also hypersensitive to these chemicals. The lipopolysaccharide contents decreased in individual imp/ostA and msbA mutants and dramatically reduced in the imp/ostA and msbA double mutant. Outer membrane permeability assay demonstrated that the imp/ostA and msbA double mutation resulted in the increase of outer membrane permeability. Ethidium bromide accumulation assay demonstrated that MsbA was involved in efflux of hydrophobic drugs. Conclusion The expression levels of imp/ostA and msbA were correlated with glutaraldehyde resistance in clinical isolates after glutaraldehyde treatment. Imp/OstA and MsbA play a synergistic role in hydrophobic drugs resistance and lipopolysaccharide biogenesis in H. pylori.
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Affiliation(s)
- Hung-Chuan Chiu
- Department of Microbiology, National Taiwan University College of Medicine, Taipei City 10051, Taiwan, Republic of China.
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Franco AT, Friedman DB, Nagy TA, Romero-Gallo J, Krishna U, Kendall A, Israel DA, Tegtmeyer N, Washington MK, Peek RM. Delineation of a carcinogenic Helicobacter pylori proteome. Mol Cell Proteomics 2009; 8:1947-58. [PMID: 19470446 DOI: 10.1074/mcp.m900139-mcp200] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Helicobacter pylori is the strongest known risk factor for gastric adenocarcinoma, yet only a fraction of infected persons ever develop cancer. The extensive genetic diversity inherent to this pathogen has precluded comprehensive analyses of constituents that mediate carcinogenesis. We previously reported that in vivo adaptation of a non-carcinogenic H. pylori strain endowed the output derivative with the ability to induce adenocarcinoma, providing a unique opportunity to identify proteins selectively expressed by an oncogenic H. pylori strain. Using a global proteomics DIGE/MS approach, a novel missense mutation of the flagellar protein FlaA was identified that affects structure and function of this virulence-related organelle. Among 25 additional differentially abundant proteins, this approach also identified new proteins previously unassociated with gastric cancer, generating a profile of H. pylori proteins to use in vaccine development and for screening persons infected with strains most likely to induce severe disease.
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Affiliation(s)
- Aime T Franco
- Division of Gastroenterology, Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-2279, USA
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Smith TG, Pereira L, Hoover TR. Helicobacter pylori FlhB processing-deficient variants affect flagellar assembly but not flagellar gene expression. MICROBIOLOGY-SGM 2009; 155:1170-1180. [PMID: 19332819 DOI: 10.1099/mic.0.022806-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Regulation of the Helicobacter pylori flagellar gene cascade involves the transcription factors sigma(54) (RpoN), employed for expression of genes required midway through flagellar assembly, and sigma(28) (FliA), required for expression of late genes. Previous studies revealed that mutations in genes encoding components of the flagellar protein export apparatus block expression of the H. pylori RpoN and FliA regulons. FlhB is a membrane-bound component of the export apparatus that possesses a large cytoplasmic domain (FlhB(C)). The hook length control protein FliK interacts with FlhB(C) to modulate the substrate specificity of the export apparatus. FlhB(C) undergoes autocleavage as part of the switch in substrate specificity. Consistent with previous reports, deletion of flhB in H. pylori interfered with expression of RpoN-dependent reporter genes, while deletion of fliK stimulated expression of these reporter genes. In the DeltaflhB mutant, disrupting fliK did not restore expression of RpoN-dependent reporter genes, suggesting that the inhibitory effect of the DeltaflhB mutation is not due to the inability to export FliK. Amino acid substitutions (N265A and P266G) at the putative autocleavage site of H. pylori FlhB prevented processing of FlhB and export of filament-type substrates. The FlhB variants supported wild-type expression of RpoN- and FliA-dependent reporter genes. In the strain producing FlhB(N265A), expression of RpoN- and FliA-dependent reporter genes was inhibited when fliK was disrupted. In contrast, expression of these reporter genes was unaffected or slightly stimulated when fliK was disrupted in the strain producing FlhB(P266G). H. pylori HP1575 (FlhX) shares homology with the C-terminal portion of FlhB(C) (FlhB(CC)) and can substitute for FlhB(CC) in flagellar assembly. Disrupting flhX inhibited expression of a flaB reporter gene in the wild-type but not in the DeltafliK mutant or strains producing FlhB variants, suggesting a role for FlhX or FlhB(CC) in normal expression of the RpoN regulon. Taken together, these data indicate that the mechanism by which the flagellar protein export apparatus exerts control over the H. pylori RpoN regulon is complex and involves more than simply switching substrate specificity of the flagellar protein export apparatus.
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Affiliation(s)
- Todd G Smith
- Department of Microbiology, University of Georgia, Athens, GA 30602, USA
| | - Lara Pereira
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Timothy R Hoover
- Department of Microbiology, University of Georgia, Athens, GA 30602, USA
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