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Ren Z, Yang Z, Yuan H, Song Y, He H, Nie L, Wang X, Yuan ZG, Zhang XX. 4D label-free proteomic analysis reveals key potential pathways of Toxoplasma invasion into the central nervous system. Int Immunopharmacol 2024; 138:112618. [PMID: 38996663 DOI: 10.1016/j.intimp.2024.112618] [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: 04/01/2024] [Revised: 06/19/2024] [Accepted: 06/30/2024] [Indexed: 07/14/2024]
Abstract
Toxoplasma gondii is a successful parasite capable of infecting a wide range of warm-blooded animals, including people, livestock, and wildlife. In individuals with intact immune function, T. gondii can invade the host brain tissue by altering the blood-brain barrier permeability, leading to chronic infection. Proteins play crucial regulatory roles in disease progression. By monitoring changes in proteins, a deeper understanding of the molecular mechanisms underlying host resistance to infection and the potential pathogenic mechanisms of pathogens can be gained. This study analyzed differential protein expression and associated signaling pathways in mouse brain tissues during acute and chronic T. gondii infection using proteomic and bioinformatics methods. The results showed that during acute and chronic T. gondii infection stages, 74 and 498 differentially expressed proteins (DEPs) were identified in mouse brain tissue, respectively. Among them, 45 and 309 were up-regulated, while 29 and 189 were down-regulated. GO and KEGG analyses revealed that some of these DEPs were implicated in host immunity, pathogen immune evasion, and T. gondii invasion of the central nervous system, particularly interleukin production and secretion, complement system activation, and alterations in tight junction pathways. Notably, the upregulation of Rab13 was identified as a potential molecular mechanism for T. gondii to regulate blood-brain barrier permeability and facilitate central nervous system invasion. Our findings provided fundamental data for understanding host control of Toxoplasmosis infection and offered new insights into parasite immune evasion and invasion mechanisms within the central nervous system. These insights are crucial for developing strategies to prevent the establishment of chronic T. gondii infection.
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Affiliation(s)
- Zhaowen Ren
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, College of Veterinary Medicine, South China Agricultural University, Guangzhou, Guangdong, China; Key Laboratory of Livestock Disease Prevention of Guangdong Province, Scientific Observation and Key Laboratory for Prevention and Control of Avian Influenza and Other Major Poultry Diseases, Ministry of Agriculture and Rural Affairs, Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Baishigang, Wushan Street, Tianhe District, Guangzhou 510640, China
| | - Zipeng Yang
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, College of Veterinary Medicine, South China Agricultural University, Guangzhou, Guangdong, China
| | - Hao Yuan
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, College of Veterinary Medicine, South China Agricultural University, Guangzhou, Guangdong, China
| | - Yining Song
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, College of Veterinary Medicine, South China Agricultural University, Guangzhou, Guangdong, China
| | - Houjing He
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, College of Veterinary Medicine, South China Agricultural University, Guangzhou, Guangdong, China
| | - Linchong Nie
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, College of Veterinary Medicine, South China Agricultural University, Guangzhou, Guangdong, China
| | - Xiaohu Wang
- Key Laboratory of Livestock Disease Prevention of Guangdong Province, Scientific Observation and Key Laboratory for Prevention and Control of Avian Influenza and Other Major Poultry Diseases, Ministry of Agriculture and Rural Affairs, Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Baishigang, Wushan Street, Tianhe District, Guangzhou 510640, China.
| | - Zi-Guo Yuan
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, College of Veterinary Medicine, South China Agricultural University, Guangzhou, Guangdong, China.
| | - Xiu-Xiang Zhang
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, College of Veterinary Medicine, South China Agricultural University, Guangzhou, Guangdong, China.
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Guo Y, Xiao R, Feng J, Wang X, Lai J, Kang W, Li Y, Zhu X, Ji T, Huang X, Pang D, An Y, Meng L, Wang Y. Distribution of virulence genes and antimicrobial resistance of Escherichia coli isolated from hospitalized neonates: A multi-center study across China. Heliyon 2024; 10:e35991. [PMID: 39229497 PMCID: PMC11369463 DOI: 10.1016/j.heliyon.2024.e35991] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2024] [Revised: 07/14/2024] [Accepted: 08/07/2024] [Indexed: 09/05/2024] Open
Abstract
Background Escherichia coli is the most common gram-negative pathogen to cause neonatal infections. Contemporary virulence characterization and antimicrobial resistance (AMR) data of neonatal E. coli isolates in China are limited. Methods A total of 159 E. coli strains isolated from neonates were collected and classified into invasive and non-invasive infection groups, according to their site of origin. The presence of virulence genes was determined using polymerase chain reaction (PCR). All the strains were subjected to antimicrobial susceptibility testing using the broth dilution method. Results The top three virulence genes with the highest detection rates were fimH (90.6 %), iutA (88.7 %), and kspMT II (88.1 %). The prevalences of fyuA (p = 0.023), kpsMT K1 (p = 0.019), ibeA (p < 0.001), and iroN (p = 0.027) were significantly higher in the invasive infection group than in the non-invasive infection group. Resistance to ceftazixime, sulfamethoxazole/trimethoprim, and ciprofloxacin was 75.5 %, 65.4 %, and 48.4 %, respectively. Lower rates of resistance to ceftazidime (p = 0.022), cefepime (p = 0.005), ticarcillin/clavulanic acid (p = 0.020) and aztreonam (p = 0.001) were observed in the invasive infection group compared to the non-invasive infection group. The number of virulence genes carried by E. coli was positively correlated with the number of antibiotics to which the isolates were resistant (r = 0.71, p = 0.016), and a specific virulence gene was associated with resistance to various species of antibiotics. Conclusions Neonatal E. coli isolates carried multiple virulence genes and were highly resistant to antibiotics. Further studies are needed to understand the molecular mechanisms underlying the association between virulence and AMR.
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Affiliation(s)
- Yuting Guo
- Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, China
- Department of Neonatology, Fifth Medical Center of Chinese PLA General Hospital, Beijing, China
| | - Ruiqi Xiao
- Capital Institute of Pediatrics, Beijing, China
| | - Jinxing Feng
- Department of Neonatology, Shenzhen Children's Hospital, Shenzhen, China
| | - Xiaoyun Wang
- Inner Mongolia Maternity and Child Health Care Hospital, Inner Mongolia, China
| | - Jidong Lai
- Department of Neonatology, Women and Children's Hospital, School of Medicine, Xiamen University, Xiamen, Fujian, China
| | - Wenqing Kang
- Neonatal Intensive Care Unit, Children's Hospital Affiliated to Zhengzhou University, Henan Children's Hospital, Zhengzhou, Henan, China
| | - Yangfang Li
- Department of Neonatology, Children's Hospital of Kunming, Kunming, Yunnan, China
| | - Xueping Zhu
- Department of Neonatology, Children's Hospital of Soochow University, Suzhou City, Jiangsu Province, China
| | - Tongzhen Ji
- Clinical Laboratory, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing Maternal and Child Health Care Hospital, Beijing, China
| | - Xuerong Huang
- Department of Neonatology, Women and Children's Hospital, School of Medicine, Xiamen University, Xiamen, Fujian, China
| | - Dan Pang
- Clinical Laboratory,Inner Mongolia Maternity and Child Health Care Hospital,Inner Mongolia, China
| | - Yanbin An
- Inner Mongolia Maternity and Child Health Care Hospital, Inner Mongolia, China
| | - Lihui Meng
- Department of Infectious Diseases, Children's Hospital, Capital Institute of Pediatrics, 2# Yabao Road, Chaoyang District, Beijing 100020, China
| | - Yajuan Wang
- Department of Neonatology, Children's Hospital, Capital Institute of Pediatrics, 2# Yabao Road, Chaoyang District, Beijing 100020, China
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Poteete O, Cox P, Ruffin F, Sutton G, Brinkac L, Clarke TH, Fouts DE, Fowler VG, Thaden JT. Serum susceptibility of Escherichia coli and its association with patient clinical outcomes. PLoS One 2024; 19:e0307968. [PMID: 39074102 DOI: 10.1371/journal.pone.0307968] [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: 03/15/2024] [Accepted: 07/14/2024] [Indexed: 07/31/2024] Open
Abstract
The innate immune system eliminates bloodstream pathogens such as Escherichia coli in part through complement protein deposition and subsequent bacterial death (i.e., "serum killing"). Some E. coli strains have developed mechanisms to resist serum killing, though the extent of variation in serum killing among bloodstream infection (BSI) isolates and the clinical impact of this variation is not well understood. To address this issue, we developed a novel assay that uses flow cytometry to perform high throughput serum bactericidal assays (SBAs) with E. coli BSI isolates (n = 183) to define the proportion of surviving bacteria after exposure to serum. We further determined whether E. coli resistance to serum killing is associated with clinical outcomes (e.g., in-hospital attributable mortality, in-hospital total mortality, septic shock) and bacterial genotype in the corresponding patients with E. coli BSI. Our novel flow cytometry-based SBA performed similarly to a traditional SBA, though with significantly decreased hands-on bench work. Among E. coli BSI isolates, the mean proportion that survived exposure to 25% serum was 0.68 (Standard deviation 0.02, range 0.57-0.93). We did not identify associations between E. coli resistance to serum killing and clinical outcomes in our adjusted models. Together, this study describes a novel flow cytometry-based approach to the bacterial SBA that allowed for high-throughput testing of E. coli BSI isolates and identified high variability in resistance to serum killing among a large set of BSI isolates.
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Affiliation(s)
- Orianna Poteete
- Department of Medicine, Division of Infectious Diseases, Duke University School of Medicine, Durham, NC, United States of America
| | - Phillip Cox
- Department of Medicine, Division of Infectious Diseases, Duke University School of Medicine, Durham, NC, United States of America
| | - Felicia Ruffin
- Department of Medicine, Division of Infectious Diseases, Duke University School of Medicine, Durham, NC, United States of America
| | - Granger Sutton
- J. Craig Venter Institute, Rockville, MD, United States of America
| | - Lauren Brinkac
- J. Craig Venter Institute, Rockville, MD, United States of America
| | - Thomas H Clarke
- J. Craig Venter Institute, Rockville, MD, United States of America
| | - Derrick E Fouts
- J. Craig Venter Institute, Rockville, MD, United States of America
| | - Vance G Fowler
- Department of Medicine, Division of Infectious Diseases, Duke University School of Medicine, Durham, NC, United States of America
- Duke Clinical Research Institute, Durham, NC, United States of America
| | - Joshua T Thaden
- Department of Medicine, Division of Infectious Diseases, Duke University School of Medicine, Durham, NC, United States of America
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Lê-Bury P, Echenique-Rivera H, Pizarro-Cerdá J, Dussurget O. Determinants of bacterial survival and proliferation in blood. FEMS Microbiol Rev 2024; 48:fuae013. [PMID: 38734892 PMCID: PMC11163986 DOI: 10.1093/femsre/fuae013] [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: 11/06/2023] [Revised: 04/29/2024] [Accepted: 05/10/2024] [Indexed: 05/13/2024] Open
Abstract
Bloodstream infection is a major public health concern associated with high mortality and high healthcare costs worldwide. Bacteremia can trigger fatal sepsis whose prevention, diagnosis, and management have been recognized as a global health priority by the World Health Organization. Additionally, infection control is increasingly threatened by antimicrobial resistance, which is the focus of global action plans in the framework of a One Health response. In-depth knowledge of the infection process is needed to develop efficient preventive and therapeutic measures. The pathogenesis of bloodstream infection is a dynamic process resulting from the invasion of the vascular system by bacteria, which finely regulate their metabolic pathways and virulence factors to overcome the blood immune defenses and proliferate. In this review, we highlight our current understanding of determinants of bacterial survival and proliferation in the bloodstream and discuss their interactions with the molecular and cellular components of blood.
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Affiliation(s)
- Pierre Lê-Bury
- Institut Pasteur, Université Paris Cité, CNRS UMR6047, Yersinia Research Unit, 28 rue du Dr Roux, 75015 Paris, France
- Université Paris-Saclay, Inserm, CEA, Center for Immunology of Viral, Autoimmune, Hematological and Bacterial Diseases (IMVA-HB/IDMIT), 18 route du Panorama, 92260 Fontenay-aux-Roses, France
| | - Hebert Echenique-Rivera
- Institut Pasteur, Université Paris Cité, CNRS UMR6047, Yersinia Research Unit, 28 rue du Dr Roux, 75015 Paris, France
| | - Javier Pizarro-Cerdá
- Institut Pasteur, Université Paris Cité, CNRS UMR6047, Yersinia Research Unit, 28 rue du Dr Roux, 75015 Paris, France
- Institut Pasteur, Université Paris Cité, Yersinia National Reference Laboratory, WHO Collaborating Research & Reference Centre for Plague FRA-146, 28 rue du Dr Roux, 75015 Paris, France
| | - Olivier Dussurget
- Institut Pasteur, Université Paris Cité, CNRS UMR6047, Yersinia Research Unit, 28 rue du Dr Roux, 75015 Paris, France
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Correa GB, Freire CA, Dibo M, Huerta-Cantillo J, Navarro-Garcia F, Barbosa AS, Elias WP, Moraes CTP. Plasmid-encoded toxin of Escherichia coli cleaves complement system proteins and inhibits complement-mediated lysis in vitro. Front Cell Infect Microbiol 2024; 14:1327241. [PMID: 38371299 PMCID: PMC10869522 DOI: 10.3389/fcimb.2024.1327241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Accepted: 01/08/2024] [Indexed: 02/20/2024] Open
Abstract
Plasmid-encoded toxin (Pet) is an autotransporter protein of the serine protease autotransporters of Enterobacteriaceae (SPATE) family, important in the pathogenicity of Escherichia coli. The pet gene was initially found in the enteroaggregative E. coli (EAEC) virulence plasmid, pAA2. Although this virulence factor was initially described in EAEC, an intestinal E. coli pathotype, pet may also be present in other pathotypes, including extraintestinal pathogenic strains (ExPEC). The complement system is an important defense mechanism of the immune system that can be activated by invading pathogens. Proteases produced by pathogenic bacteria, such as SPATEs, have proteolytic activity and can cleave components of the complement system, promoting bacterial resistance to human serum. Considering these factors, the proteolytic activity of Pet and its role in evading the complement system were investigated. Proteolytic assays were performed by incubating purified components of the complement system with Pet and Pet S260I (a catalytic site mutant) proteins. Pet, but not Pet S260I, could cleave C3, C5 and C9 components, and also inhibited the natural formation of C9 polymers. Furthermore, a dose-dependent inhibition of ZnCl2-induced C9 polymerization in vitro was observed. E. coli DH5α survived incubation with human serum pre-treated with Pet. Therefore, Pet can potentially interfere with the alternative and the terminal pathways of the complement system. In addition, by cleaving C9, Pet may inhibit membrane attack complex (MAC) formation on the bacterial outer membrane. Thus, our data are suggestive of a role of Pet in resistance of E. coli to human serum.
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Affiliation(s)
| | | | - Miriam Dibo
- Laboratório de Bacteriologia, Instituto Butantan, São Paulo, Brazil
| | - Jazmin Huerta-Cantillo
- Department of Cell Biology, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (IPN), Mexico City, Mexico
| | - Fernando Navarro-Garcia
- Department of Cell Biology, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (IPN), Mexico City, Mexico
| | | | - Waldir P. Elias
- Laboratório de Bacteriologia, Instituto Butantan, São Paulo, Brazil
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Acharya R, Clapp WL, Upadhyay K. Efficacy and Safety of Eculizumab in Enteroaggregative E. coli Associated Hemolytic Uremic Syndrome. Pediatr Rep 2024; 16:26-34. [PMID: 38251312 PMCID: PMC10801546 DOI: 10.3390/pediatric16010003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Revised: 12/22/2023] [Accepted: 12/29/2023] [Indexed: 01/23/2024] Open
Abstract
BACKGROUND Hemolytic uremic syndrome (HUS) may present atypically without the full triad of classical HUS. Eculizumab has been shown to be efficacious in complement-mediated atypical HUS and some cases of Shiga-toxin (ST) associated HUS. We report the utility of eculizumab in enteroaggregative E. coli (EAEC) associated HUS. CASE SUMMARY A female toddler presented with hemolytic anemia, oliguric acute kidney injury (AKI) without thrombocytopenia, and peripheral schistocytes. The stool examination for ST was negative but positive for EAEC. She required several hemodialysis sessions and received one dosage of eculizumab with rapid reversal of AKI and hemolytic markers. A kidney biopsy revealed acute tubular injury and segmental glomerular basement membrane splitting. Genetic testing was negative for complement mutations or deficiencies. A follow-up six months later showed persistently normal renal function and hematological markers. CONCLUSION The clinical and histological manifestations of non-ST-associated diarrheal HUS and the role of eculizumab in this condition warrant future larger studies.
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Affiliation(s)
- Ratna Acharya
- Division of Pediatric Emergency Medicine, Department of Pediatrics, Nemours Children’s Hospital, Orlando, FL 32827, USA;
| | - William L. Clapp
- Division of Anatomic Pathology, Department of Pathology, University of Florida, Gainesville, FL 32610, USA;
| | - Kiran Upadhyay
- Division of Pediatric Nephrology, Department of Pediatrics, University of Florida, Gainesville, FL 32610, USA
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Arredondo-Alonso S, Blundell-Hunter G, Fu Z, Gladstone RA, Fillol-Salom A, Loraine J, Cloutman-Green E, Johnsen PJ, Samuelsen Ø, Pöntinen AK, Cléon F, Chavez-Bueno S, De la Cruz MA, Ares MA, Vongsouvath M, Chmielarczyk A, Horner C, Klein N, McNally A, Reis JN, Penadés JR, Thomson NR, Corander J, Taylor PW, McCarthy AJ. Evolutionary and functional history of the Escherichia coli K1 capsule. Nat Commun 2023; 14:3294. [PMID: 37322051 PMCID: PMC10272209 DOI: 10.1038/s41467-023-39052-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2023] [Accepted: 05/26/2023] [Indexed: 06/17/2023] Open
Abstract
Escherichia coli is a leading cause of invasive bacterial infections in humans. Capsule polysaccharide has an important role in bacterial pathogenesis, and the K1 capsule has been firmly established as one of the most potent capsule types in E. coli through its association with severe infections. However, little is known about its distribution, evolution and functions across the E. coli phylogeny, which is fundamental to elucidating its role in the expansion of successful lineages. Using systematic surveys of invasive E. coli isolates, we show that the K1-cps locus is present in a quarter of bloodstream infection isolates and has emerged in at least four different extraintestinal pathogenic E. coli (ExPEC) phylogroups independently in the last 500 years. Phenotypic assessment demonstrates that K1 capsule synthesis enhances E. coli survival in human serum independent of genetic background, and that therapeutic targeting of the K1 capsule re-sensitizes E. coli from distinct genetic backgrounds to human serum. Our study highlights that assessing the evolutionary and functional properties of bacterial virulence factors at population levels is important to better monitor and predict the emergence of virulent clones, and to also inform therapies and preventive medicine to effectively control bacterial infections whilst significantly lowering antibiotic usage.
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Affiliation(s)
- Sergio Arredondo-Alonso
- Department of Biostatistics, University of Oslo, 0317, Oslo, Norway
- Parasites and Microbes, Wellcome Sanger Institute, Cambridge, UK
| | | | - Zuyi Fu
- Department of Infectious Disease, Centre for Bacterial Resistance Biology, Imperial College London, London, UK
| | - Rebecca A Gladstone
- Department of Biostatistics, University of Oslo, 0317, Oslo, Norway
- Parasites and Microbes, Wellcome Sanger Institute, Cambridge, UK
| | - Alfred Fillol-Salom
- Department of Infectious Disease, Centre for Bacterial Resistance Biology, Imperial College London, London, UK
| | | | - Elaine Cloutman-Green
- Great Ormond Street Institute of Child Health, University College London, London, UK
| | - Pål J Johnsen
- Department of Pharmacy, Faculty of Health Sciences, UiT The Arctic University of Norway, Tromsø, Norway
| | - Ørjan Samuelsen
- Department of Pharmacy, Faculty of Health Sciences, UiT The Arctic University of Norway, Tromsø, Norway
- Norwegian National Advisory Unit on Detection of Antimicrobial Resistance, Department of Microbiology and Infection Control, University Hospital of North Norway, Tromsø, Norway
| | - Anna K Pöntinen
- Department of Biostatistics, University of Oslo, 0317, Oslo, Norway
- Norwegian National Advisory Unit on Detection of Antimicrobial Resistance, Department of Microbiology and Infection Control, University Hospital of North Norway, Tromsø, Norway
| | - François Cléon
- Department of Pharmacy, Faculty of Health Sciences, UiT The Arctic University of Norway, Tromsø, Norway
| | - Susana Chavez-Bueno
- University of Missouri Kansas City, Kansas City, USA
- Division of Infectious Diseases, Children's Mercy Hospital Kansas City, UMKC School of Medicine, Kansas City, USA
| | - Miguel A De la Cruz
- Unidad de Investigación Médica en Enfermedades Infecciosas y Parasitarias, Hospital de Pediatría, Centro Médico Nacional Siglo XXI Instituto Mexicano del Seguro Social, Mexico City, Mexico
- Facultad de Medicina, Benemérita Universidad Autónoma de Puebla, Puebla, Mexico
| | - Miguel A Ares
- Unidad de Investigación Médica en Enfermedades Infecciosas y Parasitarias, Hospital de Pediatría, Centro Médico Nacional Siglo XXI Instituto Mexicano del Seguro Social, Mexico City, Mexico
| | - Manivanh Vongsouvath
- Lao-Oxford-Mahosot Hospital-Wellcome Trust Research Unit (LOMWRU), Microbiology Laboratory, Mahosot Hospital, Vientiane, Lao PDR
| | - Agnieszka Chmielarczyk
- Faculty of Medicine, Chair of Microbiology, Jagiellonian University Medical College, Czysta str. 18, 31-121, Kraków, Poland
| | - Carolyne Horner
- British Society for Antimicrobial Chemotherapy, Birmingham, UK
| | - Nigel Klein
- Great Ormond Street Institute of Child Health, University College London, London, UK
| | - Alan McNally
- Institute of Microbiology and Infection, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK
| | - Joice N Reis
- Laboratory of Pathology and Molecular Biology (LPBM), Gonçalo Moniz Research Institute, Oswaldo Cruz Foundation, Salvador, Brazil
- Faculdade de Farmácia, Universidade Federal da Bahia, Salvador, Brazil
| | - José R Penadés
- Department of Infectious Disease, Centre for Bacterial Resistance Biology, Imperial College London, London, UK
| | - Nicholas R Thomson
- Parasites and Microbes, Wellcome Sanger Institute, Cambridge, UK
- London School of Hygiene and Tropical Medicine, London, UK
| | - Jukka Corander
- Department of Biostatistics, University of Oslo, 0317, Oslo, Norway.
- Parasites and Microbes, Wellcome Sanger Institute, Cambridge, UK.
- Helsinki Institute of Information Technology, Department of Mathematics and Statistics, University of Helsinki, Helsinki, Finland.
| | - Peter W Taylor
- School of Pharmacy, University College London, London, UK.
| | - Alex J McCarthy
- Department of Infectious Disease, Centre for Bacterial Resistance Biology, Imperial College London, London, UK.
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Jalil A, Masood S, Ain Q, Andleeb S, Dudley EG, Adnan F. High resistance of fluoroquinolone and macrolide reported in avian pathogenic Escherichia coli isolates from the humid subtropical regions of Pakistan. J Glob Antimicrob Resist 2023; 33:5-17. [PMID: 36764657 DOI: 10.1016/j.jgar.2023.01.009] [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: 10/07/2022] [Revised: 01/20/2023] [Accepted: 01/25/2023] [Indexed: 02/11/2023] Open
Abstract
OBJECTIVES This study aimed to assess the antimicrobial resistance profile, virulence potential, and genetic characterization of avian pathogenic Escherichia coli (APEC) that cause colibacillosis in poultry. METHODS Antibiotic susceptibility testing (AST) was measured via the Kirby-Bauer disc diffusion method against 27 commonly used antibiotics. Phylogrouping, virulence-associated gene detection, and hybrid strain detection via multiplex polymerase chain reaction (PCR) and genetic diversity were analysed via ERIC-PCR fingertyping method. RESULTS AST analysis showed 100% of isolates were multidrug-resistant (MDR) and highest resistance was against penicillin, tetracycline, and macrolide classes of antibiotics. The mcr-1 gene was present in 40% of the isolates, though only 4% of isolates were showing phenotypic resistance. Despite the scarce use of fluoroquinolone, carbapenem, and cephalosporin in the poultry sector, resistance was evident because of the high prevalence of extended-spectrum β-lactamase (ESBL) (53.7%) and other β-lactamases in APEC isolates. β-lactamase genotyping of APEC isolates revealed that 85.7% of isolates contained either blaCTX or blaTEM and around 38% of isolates were complement resistant. Growth in human urine was evident in 67.3% of isolates. Phylogroup B1 (51%) was the most prevalent group followed by phylogroups A (30.6%), D (13.61%), and B2 (4.76%). The most prevalent virulence-associated genes were fimH, iss, and tatT. Results showed that 26 isolates (17.69%) can be termed hybrid strains and APEC/EHEC (enterohemorrhagic E. coli) was the most prevalent hybrid E. coli pathotype. ERIC-PCR fingerprinting genotype analysis clustered APEC isolates in 40 groups (E1-E40). This study provides insights into the antibiotic resistance and virulence profiling of the APEC isolates in Pakistan. CONCLUSIONS The findings of this study provide insights into that the antibiotic resistance and virulence profiling of the APEC isolates in Pakistan. This data can inform future studies designed to better estimate the severity of the colibacillosis in poultry farms.
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Affiliation(s)
- Amna Jalil
- Atta Ur Rahman School of Applied Biosciences, National University of Sciences and Technology, Islamabad, Pakistan
| | - Saleha Masood
- Atta Ur Rahman School of Applied Biosciences, National University of Sciences and Technology, Islamabad, Pakistan
| | - Quratul Ain
- Atta Ur Rahman School of Applied Biosciences, National University of Sciences and Technology, Islamabad, Pakistan
| | - Saadia Andleeb
- Atta Ur Rahman School of Applied Biosciences, National University of Sciences and Technology, Islamabad, Pakistan
| | - Edward G Dudley
- Department of Food Sciences, Pennsylvania State University, University Park, Pennsylvania; Escherichia coli Reference Centre, Pennsylvania State University, University Park, Pennsylvania
| | - Fazal Adnan
- Atta Ur Rahman School of Applied Biosciences, National University of Sciences and Technology, Islamabad, Pakistan.
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9
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Dong A, Liu C, Hua X, Yu Y, Guo Y, Wang D, Liu X, Chen H, Wang H, Zhu L. Bioinformatic analysis of structures and encoding genes of Escherichia coli surface polysaccharides sheds light on the heterologous biosynthesis of glycans. BMC Genomics 2023; 24:168. [PMID: 37016299 PMCID: PMC10072801 DOI: 10.1186/s12864-023-09269-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Accepted: 03/22/2023] [Indexed: 04/06/2023] Open
Abstract
BACKGROUND Surface polysaccharides (SPs), such as lipopolysaccharide (O antigen) and capsular polysaccharide (K antigen), play a key role in the pathogenicity of Escherichia coli (E. coli). Gene cluster for polysaccharide antigen biosynthesis encodes various glycosyltransferases (GTs), which drive the process of SP synthesis and determine the serotype. RESULTS In this study, a total of 7,741 E. coli genomic sequences were chosen for systemic data mining. The monosaccharides in both O and K antigens were dominated by D-hexopyranose, and the SPs in 70-80% of the strains consisted of only the five most common hexoses (or some of them). The linkages between the two monosaccharides were mostly α-1,3 (23.15%) and β-1,3 (20.49%) bonds. Uridine diphosphate activated more than 50% of monosaccharides for glycosyltransferase reactions. These results suggest that the most common pathways could be integrated into chassis cells to promote glycan biosynthesis. We constructed a database (EcoSP, http://ecosp.dmicrobe.cn/ ) for browse this information, such as monosaccharide synthesis pathways. It can also be used for serotype analysis and GT annotation of known or novel E. coli sequences, thus facilitating the diagnosis and typing. CONCLUSIONS Summarizing and analyzing the properties of these polysaccharide antigens and GTs are of great significance for designing glycan-based vaccines and the synthetic glycobiology.
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Affiliation(s)
- Ao Dong
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Biotechnology, No. 20, Dongda Street, Fengtai District, Beijing, 100071, People's Republic of China
| | - Chengzhi Liu
- Department of Infectious Diseases, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, People's Republic of China
- Hangzhou Digital-Micro Biotech Co., Ltd, Hangzhou, People's Republic of China
| | - Xiaoting Hua
- Department of Infectious Diseases, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, People's Republic of China
- Key Laboratory of Microbial Technology and Bioinformatics of Zhejiang Province, Hangzhou, People's Republic of China
- Regional Medical Center for National Institute of Respiratory Diseases, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, People's Republic of China
| | - Yunsong Yu
- Department of Infectious Diseases, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, People's Republic of China
- Key Laboratory of Microbial Technology and Bioinformatics of Zhejiang Province, Hangzhou, People's Republic of China
- Regional Medical Center for National Institute of Respiratory Diseases, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, People's Republic of China
| | - Yan Guo
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Biotechnology, No. 20, Dongda Street, Fengtai District, Beijing, 100071, People's Republic of China
| | - Dongshu Wang
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Biotechnology, No. 20, Dongda Street, Fengtai District, Beijing, 100071, People's Republic of China
| | - Xiankai Liu
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Biotechnology, No. 20, Dongda Street, Fengtai District, Beijing, 100071, People's Republic of China
| | - Huan Chen
- Department of Infectious Diseases, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, People's Republic of China.
- Hangzhou Digital-Micro Biotech Co., Ltd, Hangzhou, People's Republic of China.
- Zhejiang Chinese Medical University, Hangzhou, People's Republic of China.
| | - Hengliang Wang
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Biotechnology, No. 20, Dongda Street, Fengtai District, Beijing, 100071, People's Republic of China.
| | - Li Zhu
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Biotechnology, No. 20, Dongda Street, Fengtai District, Beijing, 100071, People's Republic of China.
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10
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Downs CJ, Schoenle LA, Goolsby EW, Oakey SJ, Ball R, Jiang RHY, Martin LB. Large Mammals Have More Powerful Antibacterial Defenses Than Expected from Their Metabolic Rates. Am Nat 2023; 201:287-301. [PMID: 36724463 DOI: 10.1086/722504] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
AbstractTerrestrial mammals span seven orders of magnitude in body size, ranging from the <2-g Etruscan pygmy shrew (Suncus etruscus) to the >3,900-kg African elephant (Loxodonta africana). Although body size profoundly affects the behavior, physiology, ecology, and evolution of species, how investment in functional immune defenses changes with body size across species is unknown. Here, we (1) developed a novel 12-point dilution curve approach to describe and compare antibacterial capacity against three bacterial species among >160 terrestrial species of mammals and (2) tested published predictions about the scaling of immune defenses. Our study focused on the safety factor hypothesis, which predicts that broad, early-acting immune defenses should scale hypermetrically with body mass. However, our three statistical approaches demonstrated that antibacterial activity in sera across mammals exhibits isometry; killing capacity did not change with body size across species. Intriguingly, this result indicates that the serum of a large mammal is less hospitable to bacteria than would be predicted by its metabolic rates. In other words, if metabolic rates underlie the rates of physiological reactions as postulated by the metabolic theory of ecology, large species should have disproportionately lower antibacterial capacity than small species, but they do not. These results have direct implications for effectively modeling the evolution of immune defenses and identifying potential reservoir hosts of pathogens.
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11
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Crintea A, Carpa R, Mitre AO, Petho RI, Chelaru VF, Nădășan SM, Neamti L, Dutu AG. Nanotechnology Involved in Treating Urinary Tract Infections: An Overview. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:555. [PMID: 36770516 PMCID: PMC9919202 DOI: 10.3390/nano13030555] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Revised: 01/22/2023] [Accepted: 01/27/2023] [Indexed: 06/18/2023]
Abstract
Considered as the most frequent contaminations that do not require hospitalization, urinary tract infections (UTIs) are largely known to cause significant personal burdens on patients. Although UTIs overall are highly preventable health issues, the recourse to antibiotics as drug treatments for these infections is a worryingly spread approach that should be addressed and gradually overcome in a contemporary, modernized healthcare system. With a virtually alarming global rise of antibiotic resistance overall, nanotechnologies may prove to be the much-needed 'lifebuoy' that will eventually suppress this prejudicial phenomenon. This review aims to present the most promising, currently known nano-solutions, with glimpses on clinical and epidemiological aspects of the UTIs, prospective diagnostic instruments, and non-antibiotic treatments, all of these engulfed in a comprehensive overview.
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Affiliation(s)
- Andreea Crintea
- Department of Medical Biochemistry, Faculty of Medicine, Iuliu Hatieganu University of Medicine and Pharmacy, 400349 Cluj-Napoca, Romania
| | - Rahela Carpa
- Department of Molecular Biology and Biotechnology, Faculty of Biology and Geology, Babes-Bolyai University, 400084 Cluj-Napoca, Romania
| | - Andrei-Otto Mitre
- Department of Pathophysiology, Faculty of Medicine, Iuliu Hatieganu University of Medicine and Pharmacy, 400349 Cluj-Napoca, Romania
| | - Robert Istvan Petho
- Faculty of Medicine, Iuliu Hatieganu University of Medicine and Pharmacy, 400349 Cluj-Napoca, Romania
| | - Vlad-Florin Chelaru
- Faculty of Medicine, Iuliu Hatieganu University of Medicine and Pharmacy, 400349 Cluj-Napoca, Romania
| | - Sebastian-Mihail Nădășan
- Faculty of Medicine, Iuliu Hatieganu University of Medicine and Pharmacy, 400349 Cluj-Napoca, Romania
| | - Lidia Neamti
- Department of Medical Biochemistry, Faculty of Medicine, Iuliu Hatieganu University of Medicine and Pharmacy, 400349 Cluj-Napoca, Romania
| | - Alina Gabriela Dutu
- Department of Medical Biochemistry, Faculty of Medicine, Iuliu Hatieganu University of Medicine and Pharmacy, 400349 Cluj-Napoca, Romania
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12
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Jalil A, Gul S, Bhatti MF, Siddiqui MF, Adnan F. High Occurrence of Multidrug-Resistant Escherichia coli Strains in Bovine Fecal Samples from Healthy Cows Serves as Rich Reservoir for AMR Transmission. Antibiotics (Basel) 2022; 12:antibiotics12010037. [PMID: 36671238 PMCID: PMC9855024 DOI: 10.3390/antibiotics12010037] [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: 11/08/2022] [Revised: 12/11/2022] [Accepted: 12/20/2022] [Indexed: 12/28/2022] Open
Abstract
OBJECTIVES Antibiotics are valuable therapeutics. However, the unwarranted and excessive use of these antimicrobials in food animals and the consequent contamination of the environment have been associated with the emergence and spread of antimicrobial resistance. Continuous surveillance and monitoring of antimicrobial resistance among E. coli isolates is recommended, not only for bovine health but also for public health. This study aims to assess the antimicrobial resistance profile, virulence potential, and genetic characterization of fecal E. coli isolates from healthy cows. METHODOLOGY The in vitro, phenotypic antibiotic resistance of isolates was measured via the Kirby-Bauer disc-diffusion method against twenty-seven antibiotics. The β-lactamase enzymatic activities of the strains were also investigated. For the assessment of virulence potential, fecal E. coli isolates were subjected to several in vitro pathogenicity assays, including biofilm formation ability, blood hemolysis, complement resistance, and growth in human urine. Phylogroup determination and virulence-associated genes were detected via multiplex PCR. RESULTS In vitro antibiotic resistance profiling showed that 186/200 (93%) of the isolates were multidrug-resistant (MDR), with the highest resistance against penicillin, tetracycline, fluoroquinolone, and macrolide classes of antibiotics. Of particular concern was the phenotypic resistance to colistin in 52/200 isolates (26%), though 16% of the total isolates harbored mcr1, the genetic determinant of colistin. Despite the scarce use of fluoroquinolone, cephalosporin, and carbapenem in the agricultural sector, resistance to these classes was evident due to the presence of extended-spectrum β-lactamase (ESBL) in 41% of E. coli isolates. The β-lactamase genotyping of E. coli isolates showed that 47% of isolates harbored either blaCTX or blaTEM. Approximately 32% of isolates were resistant to serum complement, and their growth in human urine was evident in 18% of isolates, indicating a possible infection of these isolates in high nitrogenous condition. Phylogrouping showed that the most prevalent phylogenetic group among fecal E. coli isolates was phylogroup B1 (57%), followed by phylogroups A (33%), D (6%), and B2 (4%). The most prevalent virulence-associated genes in fecal E. coli were fimH, iss and tatT. Results showed that ten isolates (5%) harbored the stx1 gene, the genetic marker of enterohemorrhagic E. coli. This study provides insights into the antibiotic resistance and virulence profiling of the fecal E. coli isolates from healthy cows. These results emphasize the need for imposing regulations on the proper use of antibiotics and growth promoters in food-producing animals.
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Affiliation(s)
- Amna Jalil
- Atta ur Rahman School of Applied Biosciences (ASAB), National University of Sciences and Technology (NUST), Islamabad 44000, Pakistan
| | - Shabana Gul
- Atta ur Rahman School of Applied Biosciences (ASAB), National University of Sciences and Technology (NUST), Islamabad 44000, Pakistan
| | - Muhammad Faraz Bhatti
- Atta ur Rahman School of Applied Biosciences (ASAB), National University of Sciences and Technology (NUST), Islamabad 44000, Pakistan
| | | | - Fazal Adnan
- Atta ur Rahman School of Applied Biosciences (ASAB), National University of Sciences and Technology (NUST), Islamabad 44000, Pakistan
- Correspondence:
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13
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Geurtsen J, de Been M, Weerdenburg E, Zomer A, McNally A, Poolman J. Genomics and pathotypes of the many faces of Escherichia coli. FEMS Microbiol Rev 2022; 46:fuac031. [PMID: 35749579 PMCID: PMC9629502 DOI: 10.1093/femsre/fuac031] [Citation(s) in RCA: 43] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2021] [Accepted: 06/22/2022] [Indexed: 01/09/2023] Open
Abstract
Escherichia coli is the most researched microbial organism in the world. Its varied impact on human health, consisting of commensalism, gastrointestinal disease, or extraintestinal pathologies, has generated a separation of the species into at least eleven pathotypes (also known as pathovars). These are broadly split into two groups, intestinal pathogenic E. coli (InPEC) and extraintestinal pathogenic E. coli (ExPEC). However, components of E. coli's infinite open accessory genome are horizontally transferred with substantial frequency, creating pathogenic hybrid strains that defy a clear pathotype designation. Here, we take a birds-eye view of the E. coli species, characterizing it from historical, clinical, and genetic perspectives. We examine the wide spectrum of human disease caused by E. coli, the genome content of the bacterium, and its propensity to acquire, exchange, and maintain antibiotic resistance genes and virulence traits. Our portrayal of the species also discusses elements that have shaped its overall population structure and summarizes the current state of vaccine development targeted at the most frequent E. coli pathovars. In our conclusions, we advocate streamlining efforts for clinical reporting of ExPEC, and emphasize the pathogenic potential that exists throughout the entire species.
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Affiliation(s)
- Jeroen Geurtsen
- Janssen Vaccines and Prevention B.V., 2333 Leiden, the Netherlands
| | - Mark de Been
- Janssen Vaccines and Prevention B.V., 2333 Leiden, the Netherlands
| | | | - Aldert Zomer
- Department of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, 3584 Utrecht, the Netherlands
| | - Alan McNally
- Institute of Microbiology and Infection, College of Medical and Dental Sciences, University of Birmingham, B15 2TT Birmingham, United Kingdom
| | - Jan Poolman
- Janssen Vaccines and Prevention B.V., 2333 Leiden, the Netherlands
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14
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Doorduijn DJ, Lukassen MV, van 't Wout MFL, Franc V, Ruyken M, Bardoel BW, Heck AJR, Rooijakkers SHM. Soluble MAC is primarily released from MAC-resistant bacteria that potently convert complement component C5. eLife 2022; 11:77503. [PMID: 35947526 PMCID: PMC9402229 DOI: 10.7554/elife.77503] [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: 02/01/2022] [Accepted: 08/01/2022] [Indexed: 11/21/2022] Open
Abstract
The membrane attack complex (MAC or C5b-9) is an important effector of the immune system to kill invading microbes. MAC formation is initiated when complement enzymes on the bacterial surface convert complement component C5 into C5b. Although the MAC is a membrane-inserted complex, soluble forms of MAC (sMAC), or terminal complement complex (TCC), are often detected in sera of patients suffering from infections. Consequently, sMAC has been proposed as a biomarker, but it remains unclear when and how it is formed during infections. Here, we studied mechanisms of MAC formation on different Gram-negative and Gram-positive bacteria and found that sMAC is primarily formed in human serum by bacteria resistant to MAC-dependent killing. Surprisingly, C5 was converted into C5b more potently by MAC-resistant compared to MAC-sensitive Escherichia coli strains. In addition, we found that MAC precursors are released from the surface of MAC-resistant bacteria during MAC assembly. Although release of MAC precursors from bacteria induced lysis of bystander human erythrocytes, serum regulators vitronectin (Vn) and clusterin (Clu) can prevent this. Combining size exclusion chromatography with mass spectrometry profiling, we show that sMAC released from bacteria in serum is a heterogeneous mixture of complexes composed of C5b-8, up to three copies of C9 and multiple copies of Vn and Clu. Altogether, our data provide molecular insight into how sMAC is generated during bacterial infections. This fundamental knowledge could form the basis for exploring the use of sMAC as biomarker.
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Affiliation(s)
- Dennis J Doorduijn
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht, Netherlands
| | - Marie V Lukassen
- Biomolecular Mass Spectrometry and Proteomics, Utrecht University, Utrecht, Netherlands
| | - Marije F L van 't Wout
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht, Netherlands
| | - Vojtech Franc
- Biomolecular Mass Spectrometry and Proteomics, Utrecht University, Utrecht, Netherlands
| | - Maartje Ruyken
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht, Netherlands
| | - Bart W Bardoel
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht, Netherlands
| | - Albert J R Heck
- Biomolecular Mass Spectrometry and Proteomics, Utrecht University, Utrecht, Netherlands
| | - Suzan H M Rooijakkers
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht, Netherlands
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15
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Silva HGDS, Franzolin MR, dos Anjos GF, Barbosa AS, dos Santos LF, Miranda KF, Marques RM, de Souza MCL, Piazza RMF, Domingos MDO. O55 Polysaccharides Are Good Antigen Targets for the Formulation of Vaccines against O55 STEC and Capsulated aEPEC Strains. Pathogens 2022; 11:pathogens11080895. [PMID: 36015015 PMCID: PMC9414270 DOI: 10.3390/pathogens11080895] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Revised: 08/04/2022] [Accepted: 08/05/2022] [Indexed: 11/16/2022] Open
Abstract
The serogroup O55 of E. coli is composed of strains whose mechanisms of virulence are different from each other. Since the O55 polysaccharides are present in all E. coli O55 strains, and so are the polymers that compose the capsule of O55 atypical enteropathogenic E. coli (aEPEC), it was investigated whether anti-O55 antibodies were able to help the innate immune system to eliminate capsulated aEPEC and Shiga toxin-producing E. coli (STEC) belonging to the serogroup O55. The results demonstrate that the capsule of EPEC was able to inhibit the deposition of C3b on the bacterial surface and, as a consequence, their lysis by the alternative pathway of the complement system. However, in the presence of antibodies, the ability of the complement to lyse these pathogens was restored. It was also observed that macrophages were able to ingest EPEC and STEC, but they were only able to kill the ingested pathogens in the presence of antibodies. Anti-O55 antibodies were also able to inhibit aEPEC and STEC O55 adherence to human epithelial cells. In summary, the results demonstrated that the O55 polysaccharides have the potential to induce an effective humoral immune response against STEC and EPEC, indicating that they are good antigen targets to be used in vaccine formulations against these pathogens.
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Affiliation(s)
| | - Marcia Regina Franzolin
- Laboratório de Bacteriologia, Instituto Butantan, Avenida Vital Brasil, 1500, São Paulo CEP 05503-900, SP, Brazil
| | - Geovana Ferreira dos Anjos
- Laboratório de Bacteriologia, Instituto Butantan, Avenida Vital Brasil, 1500, São Paulo CEP 05503-900, SP, Brazil
| | - Angela Silva Barbosa
- Laboratório de Bacteriologia, Instituto Butantan, Avenida Vital Brasil, 1500, São Paulo CEP 05503-900, SP, Brazil
| | - Luis Fernando dos Santos
- Centro de Bacteriologia, Núcleo de Doenças Entéricas, Instituto Adolfo Lutz, Avenida Dr. Arnaldo, 355, São Paulo CEP 01246-000, SP, Brazil
| | - Kaique Ferrari Miranda
- Laboratório de Bacteriologia, Instituto Butantan, Avenida Vital Brasil, 1500, São Paulo CEP 05503-900, SP, Brazil
| | - Ronaldo Maciel Marques
- Laboratório de Bacteriologia, Instituto Butantan, Avenida Vital Brasil, 1500, São Paulo CEP 05503-900, SP, Brazil
| | - Matilde Costa Lima de Souza
- Laboratório de Bacteriologia, Instituto Butantan, Avenida Vital Brasil, 1500, São Paulo CEP 05503-900, SP, Brazil
| | - Roxane Maria Fontes Piazza
- Laboratório de Bacteriologia, Instituto Butantan, Avenida Vital Brasil, 1500, São Paulo CEP 05503-900, SP, Brazil
| | - Marta de Oliveira Domingos
- Laboratório de Bacteriologia, Instituto Butantan, Avenida Vital Brasil, 1500, São Paulo CEP 05503-900, SP, Brazil
- Correspondence: ; Tel.: +55-11-2627-9708
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Roy Chowdhury A, Sah S, Varshney U, Chakravortty D. Salmonella Typhimurium outer membrane protein A (OmpA) renders protection from nitrosative stress of macrophages by maintaining the stability of bacterial outer membrane. PLoS Pathog 2022; 18:e1010708. [PMID: 35969640 PMCID: PMC9410544 DOI: 10.1371/journal.ppat.1010708] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2021] [Revised: 08/25/2022] [Accepted: 06/27/2022] [Indexed: 11/18/2022] Open
Abstract
Bacterial porins are highly conserved outer membrane proteins used in the selective transport of charged molecules across the membrane. In addition to their significant contributions to the pathogenesis of Gram-negative bacteria, their role(s) in salmonellosis remains elusive. In this study, we investigated the role of outer membrane protein A (OmpA), one of the major outer membrane porins of Salmonella, in the pathogenesis of Salmonella Typhimurium (STM). Our study revealed that OmpA plays an important role in the intracellular virulence of Salmonella. An ompA deficient strain of Salmonella (STM ΔompA) showed compromised proliferation in macrophages. We found that the SPI-2 encoded virulence factors such as sifA and ssaV are downregulated in STM ΔompA. The poor colocalization of STM ΔompA with LAMP-1 showed that disruption of SCV facilitated its release into the cytosol of macrophages, where it was assaulted by reactive nitrogen intermediates (RNI). The enhanced recruitment of nitrotyrosine on the cytosolic population of STM ΔompAΔsifA and ΔompAΔssaV compared to STM ΔsifA and ΔssaV showed an additional role of OmpA in protecting the bacteria from host nitrosative stress. Further, we showed that the generation of greater redox burst could be responsible for enhanced sensitivity of STM ΔompA to the nitrosative stress. The expression of several other outer membrane porins such as ompC, ompD, and ompF was upregulated in STM ΔompA. We found that in the absence of ompA, the enhanced expression of ompF increased the outer membrane porosity of Salmonella and made it susceptible to in vitro and in vivo nitrosative stress. Our study illustrates a novel mechanism for the strategic utilization of OmpA by Salmonella to protect itself from the nitrosative stress of macrophages. Salmonella Typhimurium majorly uses SPI-1 and SPI-2 encoded T3SS and virulence factors for thriving in the host macrophages. But the role of non-SPI genes in Salmonella pathogenesis remains unknown. This article illustrates a novel mechanism of how a non-SPI virulent protein, OmpA, helps Salmonella Typhimurium to survive in murine macrophages. Our data revealed that Salmonella lacking OmpA (STM ΔompA) is deficient in producing SPI-2 effector proteins and has a severe defect in maintaining the stability of its outer membrane. It is released into the cytosol of macrophages during infection after disrupting the SCV membrane. STM ΔompA was severely challenged with reactive nitrogen intermediates in the cytosol, which reduced their proliferation in macrophages. We further showed that the deletion of OmpA increased the expression of other larger porins (ompC, ompD, and ompF) on the surface of Salmonella. It was observed that the enhanced expression of OmpF in STM ΔompA increased the outer membrane permeability and made the bacteria more susceptible to in vitro and in vivo nitrosative stress. Altogether our study proposes new insights into the role of Salmonella OmpA as an essential virulence factor.
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Affiliation(s)
- Atish Roy Chowdhury
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore, Karnataka, India
| | - Shivjee Sah
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore, Karnataka, India
| | - Umesh Varshney
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore, Karnataka, India
| | - Dipshikha Chakravortty
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore, Karnataka, India
- * E-mail:
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17
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Bacteria reduce flagellin synthesis to evade microglia-astrocyte-driven immunity in the brain. Cell Rep 2022; 40:111033. [PMID: 35793624 DOI: 10.1016/j.celrep.2022.111033] [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: 06/15/2021] [Revised: 05/09/2022] [Accepted: 06/13/2022] [Indexed: 11/23/2022] Open
Abstract
The immune response of brain cells to invading bacteria in vivo and the mechanism used by pathogenic bacteria to escape brain immune surveillance remain largely unknown. It is believed that microglia eliminate bacteria by phagocytosis based on in vitro data. Here we find that a small percentage of microglia in the brain engulf neonatal meningitis-causing Escherichia coli (NMEC), but more microglia are activated to produce tumor necrosis factor alpha (TNFα), which activates astrocytes to secrete complement component 3 (C3) involved in anti-bacterial activity. To evade anti-bacterial activity of the immune system, NMEC senses low concentration of threonine in cerebrospinal fluid (CSF) to down-modulate the expression of flagellin and reduce microglial TNFα and astrocyte C3 production. Our findings may help develop strategies for bacterial meningitis treatment.
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18
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Heo J. Antibacterial Effect of Various Fermentation Products and Identification of Differentially Expressed Genes of E.coli. KOREAN JOURNAL OF CLINICAL LABORATORY SCIENCE 2022. [DOI: 10.15324/kjcls.2022.54.2.119] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Affiliation(s)
- Jihye Heo
- Department of Biomedical Laboratory Science, Donggang University, Gwangju, Korea
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19
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Edwardsiella tarda TraT is an anti-complement factor and a cellular infection promoter. Commun Biol 2022; 5:637. [PMID: 35768577 PMCID: PMC9243006 DOI: 10.1038/s42003-022-03587-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Accepted: 06/15/2022] [Indexed: 12/04/2022] Open
Abstract
Edwardsiella tarda is a well-known bacterial pathogen with a broad range of host, including fish, amphibians, and mammals. One eminent virulence feature of E. tarda is its strong ability to resist the killing of host serum complement, but the involving mechanism is unclear. In this report, we identified E. tarda TraT as a key player in both complement resistance and cellular invasion. TraT, a surface-localized protein, bound and recruited complement factor H onto E. tarda, whereby inhibiting complement activation via the alternative pathway. TraT also interacted with host CD46 in a specific complement control protein domain-dependent manner, whereby facilitating the cellular infection and tissue dissemination of E. tarda. Thus, by acting as an anti-complement factor and a cellular infection promoter, TraT makes an important contribution to the complement evasion and systemic infection of E. tarda. These results add insights into the pathogen-host interaction mechanism during E. tarda infection. Edwardsiella tarda TraT promotes cellular infection and serves as an anti-complement factor, shedding light on the mechanisms of E. tarda’s strong evasion of killing by the host.
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20
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Freire CA, Silva RM, Ruiz RC, Pimenta DC, Bryant JA, Henderson IR, Barbosa AS, Elias WP. Secreted Autotransporter Toxin (Sat) Mediates Innate Immune System Evasion. Front Immunol 2022; 13:844878. [PMID: 35251044 PMCID: PMC8891578 DOI: 10.3389/fimmu.2022.844878] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Accepted: 01/24/2022] [Indexed: 11/13/2022] Open
Abstract
Several strategies are used by Escherichia coli to evade the host innate immune system in the blood, such as the cleavage of complement system proteins by secreted proteases. Members of the Serine Proteases Autotransporters of Enterobacteriaceae (SPATE) family have been described as presenting proteolytic effects against complement proteins. Among the SPATE-encoding genes sat (secreted autotransporter toxin) has been detected in high frequencies among strains of E. coli isolated from bacteremia. Sat has been characterized for its cytotoxic action, but the possible immunomodulatory effects of Sat have not been investigated. Therefore, this study aimed to evaluate the proteolytic effects of Sat on complement proteins and the role in pathogenesis of BSI caused by extraintestinal E. coli (ExPEC). E. coli EC071 was selected as a Sat-producing ExPEC strain. Whole-genome sequencing showed that sat sequences of EC071 and uropathogenic E. coli CFT073 present 99% identity. EC071 was shown to be resistant to the bactericidal activity of normal human serum (NHS). Purified native Sat was used in proteolytic assays with proteins of the complement system and, except for C1q, all tested substrates were cleaved by Sat in a dose and time-dependent manner. Moreover, E. coli DH5α survived in NHS pre-incubated with Sat. EC071-derivative strains harboring sat knockout and in trans complementations producing either active or non-active Sat were tested in a murine sepsis model. Lethality was reduced by 50% when mice were inoculated with the sat mutant strain. The complemented strain producing active Sat partially restored the effect caused by the wild-type strain. The results presented in this study show that Sat presents immunomodulatory effects by cleaving several proteins of the three complement system pathways. Therefore, Sat plays an important role in the establishment of bloodstream infections and sepsis.
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Affiliation(s)
- Claudia A Freire
- Laboratório de Bacteriologia, Instituto Butantan, São Paulo, Brazil.,Institute of Microbiology and Infection, University of Birmingham, Birmingham, United Kingdom
| | - Rosa M Silva
- Departamento de Microbiologia, Imunologia e Parasitologia, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Rita C Ruiz
- Laboratório de Bacteriologia, Instituto Butantan, São Paulo, Brazil
| | - Daniel C Pimenta
- Laboratório de Bioquímica, Instituto Butantan, São Paulo, Brazil
| | - Jack A Bryant
- Institute of Microbiology and Infection, University of Birmingham, Birmingham, United Kingdom
| | - Ian R Henderson
- Institute of Microbiology and Infection, University of Birmingham, Birmingham, United Kingdom.,Institute for Molecular Bioscience, University of Queensland, Brisbane, QLD, Australia
| | - Angela S Barbosa
- Laboratório de Bacteriologia, Instituto Butantan, São Paulo, Brazil
| | - Waldir P Elias
- Laboratório de Bacteriologia, Instituto Butantan, São Paulo, Brazil
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21
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Loads of Coliforms and Fecal Coliforms and Characterization of Thermotolerant Escherichia coli in Fresh Raw Milk Cheese. Foods 2022; 11:foods11030332. [PMID: 35159482 PMCID: PMC8834472 DOI: 10.3390/foods11030332] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 01/17/2022] [Accepted: 01/20/2022] [Indexed: 12/15/2022] Open
Abstract
The aim of this study was to assess the hygienic status of raw milk cheese and determine the trends of virulence and antimicrobial resistance in thermotolerant Escherichia coli. Two hundred samples of karish, a popular Egyptian fresh raw milk cheese, were analyzed for coliforms and fecal coliforms using a standard most probable number (MPN) technique. Overall, 85% of samples were unsuitable for consumption, as they exceeded Egyptian standards for coliforms (10 MPN/g), and 65% of samples exhibited coliforms at 44.5 °C. Of 150 recovered thermotolerant strains, 140 (93.3%) were identified as E. coli. Importantly, one Shiga toxin-producing E. coli (STEC) strain carrying a striking virulence pattern, stx1−, stx2+, eae−, was detected. Eleven strains (7.8%, 11/140) showed resistance to third-generation cephalosporins. Antibiotic resistance genes included blaSHV, blaCTX-M, qnrS, tet(A), and tet(B), which were present in 4.3%, 2.8%, 0.71%, 2.1%, and 0.71% of isolates, respectively. In conclusion, this study indicated that hygienic-sanitary failures occurred throughout the production process of most retail karish cheese. Furthermore, our findings emphasize the need for adopting third-generation cephalosporin-resistant E. coli as an indicator for monitoring antimicrobial resistance in raw milk cheese to identify the potential public health burden associated with its consumption.
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22
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Anish C, Beurret M, Poolman J. Combined effects of glycan chain length and linkage type on the immunogenicity of glycoconjugate vaccines. NPJ Vaccines 2021; 6:150. [PMID: 34893630 PMCID: PMC8664855 DOI: 10.1038/s41541-021-00409-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Accepted: 11/01/2021] [Indexed: 11/09/2022] Open
Abstract
The development and use of antibacterial glycoconjugate vaccines have significantly reduced the occurrence of potentially fatal childhood and adult diseases such as bacteremia, bacterial meningitis, and pneumonia. In these vaccines, the covalent linkage of bacterial glycans to carrier proteins augments the immunogenicity of saccharide antigens by triggering T cell-dependent B cell responses, leading to high-affinity antibodies and durable protection. Licensed glycoconjugate vaccines either contain long-chain bacterial polysaccharides, medium-sized oligosaccharides, or short synthetic glycans. Here, we discuss factors that affect the glycan chain length in vaccines and review the available literature discussing the impact of glycan chain length on vaccine efficacy. Furthermore, we evaluate the available clinical data on licensed glycoconjugate vaccine preparations with varying chain lengths against two bacterial pathogens, Haemophilus influenzae type b and Neisseria meningitidis group C, regarding a possible correlation of glycan chain length with their efficacy. We find that long-chain glycans cross-linked to carrier proteins and medium-sized oligosaccharides end-linked to carriers both achieve high immunogenicity and efficacy. However, end-linked glycoconjugates that contain long untethered stretches of native glycan chains may induce hyporesponsiveness by T cell-independent activation of B cells, while cross-linked medium-sized oligosaccharides may suffer from suboptimal saccharide epitope accessibility.
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Affiliation(s)
- Chakkumkal Anish
- grid.497529.40000 0004 0625 7026Bacterial Vaccines Discovery and Early Development, Janssen Vaccines and Prevention B.V., Leiden, Netherlands
| | - Michel Beurret
- Bacterial Vaccines Discovery and Early Development, Janssen Vaccines and Prevention B.V., Leiden, Netherlands.
| | - Jan Poolman
- grid.497529.40000 0004 0625 7026Bacterial Vaccines Discovery and Early Development, Janssen Vaccines and Prevention B.V., Leiden, Netherlands
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23
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Doorduijn DJ, Heesterbeek DAC, Ruyken M, de Haas CJC, Stapels DAC, Aerts PC, Rooijakkers SHM, Bardoel BW. Polymerization of C9 enhances bacterial cell envelope damage and killing by membrane attack complex pores. PLoS Pathog 2021; 17:e1010051. [PMID: 34752492 PMCID: PMC8604303 DOI: 10.1371/journal.ppat.1010051] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 11/19/2021] [Accepted: 10/20/2021] [Indexed: 11/21/2022] Open
Abstract
Complement proteins can form membrane attack complex (MAC) pores that directly kill Gram-negative bacteria. MAC pores assemble by stepwise binding of C5b, C6, C7, C8 and finally C9, which can polymerize into a transmembrane ring of up to 18 C9 monomers. It is still unclear if the assembly of a polymeric-C9 ring is necessary to sufficiently damage the bacterial cell envelope to kill bacteria. In this paper, polymerization of C9 was prevented without affecting binding of C9 to C5b-8, by locking the first transmembrane helix domain of C9. Using this system, we show that polymerization of C9 strongly enhanced damage to both the bacterial outer and inner membrane, resulting in more rapid killing of several Escherichia coli and Klebsiella strains in serum. By comparing binding of wildtype and ‘locked’ C9 by flow cytometry, we also show that polymerization of C9 is impaired when the amount of available C9 per C5b-8 is limited. This suggests that an excess of C9 is required to efficiently form polymeric-C9. Finally, we show that polymerization of C9 was impaired on complement-resistant E. coli strains that survive killing by MAC pores. This suggests that these bacteria can specifically block polymerization of C9. All tested complement-resistant E. coli expressed LPS O-antigen (O-Ag), compared to only one out of four complement-sensitive E. coli. By restoring O-Ag expression in an O-Ag negative strain, we show that the O-Ag impairs polymerization of C9 and results in complement-resistance. Altogether, these insights are important to understand how MAC pores kill bacteria and how bacterial pathogens can resist MAC-dependent killing. In this paper, we focus on how complement proteins, an essential part of the immune system, kill Gram-negative bacteria via so-called membrane attack complex (MAC) pores. The MAC is a large pore that consists of five different proteins. The final component, C9, assembles a ring of up to 18 C9 molecules that damages the bacterial cell envelope. Here, we aimed to better understand if this polymeric-C9 ring is necessary to kill bacteria and if bacteria can interfere in its assembly. We uncover that polymerization of C9 increased the damage to the entire bacterial cell envelope, which resulted in more rapid killing of several Gram-negative species. We also show that some clinical Escherichia coli strains can block polymerization of C9 and survive MAC-dependent killing by modifying sugars in the bacterial cell envelope, namely the O-antigen of lipopolysaccharide. These insights help us to better understand how the immune system kills bacteria and how pathogenic bacteria can survive killing.
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Affiliation(s)
- Dennis J. Doorduijn
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Dani A. C. Heesterbeek
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Maartje Ruyken
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Carla J. C. de Haas
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Daphne A. C. Stapels
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Piet C. Aerts
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Suzan H. M. Rooijakkers
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Bart W. Bardoel
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht, The Netherlands
- * E-mail:
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24
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Hammers D, Carothers K, Lee S. The Role of Bacterial Proteases in Microbe and Host-microbe Interactions. Curr Drug Targets 2021; 23:222-239. [PMID: 34370632 DOI: 10.2174/1389450122666210809094100] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Revised: 06/15/2021] [Accepted: 06/16/2021] [Indexed: 11/22/2022]
Abstract
BACKGROUND Secreted proteases are an important class of factors used by bacterial to modulate their extracellular environment through the cleavage of peptides and proteins. These proteases can range from broad, general proteolytic activity to high degrees of substrate specificity. They are often involved in interactions between bacteria and other species, even across kingdoms, allowing bacteria to survive and compete within their niche. As a result, many bacterial proteases are of clinical importance. The immune system is a common target for these enzymes, and bacteria have evolved ways to use these proteases to alter immune responses for their benefit. In addition to the wide variety of human proteins that can be targeted by bacterial proteases, bacteria also use these secreted factors to disrupt competing microbes, ranging from outright antimicrobial activity to disrupting processes like biofilm formation. OBJECTIVE In this review, we address how bacterial proteases modulate host mechanisms of protection from infection and injury, including immune factors and cell barriers. We also discuss the contributions of bacterial proteases to microbe-microbe interactions, including antimicrobial and anti-biofilm dynamics. CONCLUSION Bacterial secreted proteases represent an incredibly diverse group of factors that bacteria use to shape and thrive in their microenvironment. Due to the range of activities and targets of these proteases, some have been noted for having potential as therapeutics. The vast array of bacterial proteases and their targets remains an expanding field of research, and this field has many important implications for human health.
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Affiliation(s)
- Daniel Hammers
- Department of Biological Sciences, University of Notre Dame, Galvin Hall, Notre Dame, IN 46556, United States
| | - Katelyn Carothers
- Department of Biological Sciences, University of Notre Dame, Galvin Hall, Notre Dame, IN 46556, United States
| | - Shaun Lee
- Department of Biological Sciences, University of Notre Dame, Galvin Hall, Notre Dame, IN 46556, United States
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25
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Thomas C, Nothaft H, Yadav R, Fodor C, Alemka A, Oni O, Bell M, Rada B, Szymanski CM. Characterization of ecotin homologs from Campylobacter rectus and Campylobacter showae. PLoS One 2020; 15:e0244031. [PMID: 33378351 PMCID: PMC7773321 DOI: 10.1371/journal.pone.0244031] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Accepted: 12/01/2020] [Indexed: 12/18/2022] Open
Abstract
Ecotin, first described in Escherichia coli, is a potent
inhibitor of a broad range of serine proteases including those typically
released by the innate immune system such as neutrophil elastase (NE). Here we
describe the identification of ecotin orthologs in various
Campylobacter species, including Campylobacter
rectus and Campylobacter showae residing in the
oral cavity and implicated in the development and progression of periodontal
disease in humans. To investigate the function of these ecotins in
vitro, the orthologs from C.
rectus and C. showae were
recombinantly expressed and purified from E.
coli. Using CmeA degradation/protection assays,
fluorescence resonance energy transfer and NE activity assays, we found that
ecotins from C. rectus and C.
showae inhibit NE, factor Xa and trypsin, but not the
Campylobacter jejuni serine protease HtrA or its ortholog
in E. coli, DegP. To further evaluate ecotin
function in vivo, an E. coli
ecotin-deficient mutant was complemented with the C.
rectus and C. showae
homologs. Using a neutrophil killing assay, we demonstrate that the low survival
rate of the E. coli ecotin-deficient mutant
can be rescued upon expression of ecotins from C.
rectus and C. showae. In
addition, the C. rectus and
C. showae ecotins partially compensate for
loss of N-glycosylation and increased protease susceptibility in the related
pathogen, Campylobacter jejuni, thus implicating a similar role
for these proteins in the native host to cope with the protease-rich environment
of the oral cavity.
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Affiliation(s)
- Cody Thomas
- Department of Microbiology and Complex Carbohydrate Research Center,
University of Georgia, Athens, Georgia, United States of
America
| | - Harald Nothaft
- Department of Biological Sciences, University of Alberta, Edmonton,
Alberta, Canada
| | - Ruchi Yadav
- Department of Infectious Diseases, University of Georgia, Athens,
Georgia, United States of America
| | - Christopher Fodor
- Department of Biological Sciences, University of Alberta, Edmonton,
Alberta, Canada
| | - Abofu Alemka
- Department of Biological Sciences, University of Alberta, Edmonton,
Alberta, Canada
| | - Oluwadamilola Oni
- Department of Infectious Diseases, University of Georgia, Athens,
Georgia, United States of America
| | - Michael Bell
- Department of Infectious Diseases, University of Georgia, Athens,
Georgia, United States of America
| | - Balázs Rada
- Department of Infectious Diseases, University of Georgia, Athens,
Georgia, United States of America
| | - Christine M. Szymanski
- Department of Microbiology and Complex Carbohydrate Research Center,
University of Georgia, Athens, Georgia, United States of
America
- Department of Biological Sciences, University of Alberta, Edmonton,
Alberta, Canada
- * E-mail:
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26
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Pirdel L, Pirdel M. A Differential Immune Modulating Role of Vitamin D in Urinary Tract Infection. Immunol Invest 2020; 51:531-545. [PMID: 33353437 DOI: 10.1080/08820139.2020.1845723] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Vitamin D is known as an important modulator of numerous immune functions. We aimed to investigate the association of 25-hydroxyvitamin D [25(OH)D] with several humoral mediators of the immune system in the patients with urinary tract infection (UTI) caused by uropathogenic E. coli (UPEC). Serum levels of 25(OH)D, cytokines (interferon (IFN)-γ, interleukin (IL)-4, IL-6, IL-10, IL-17A, tumor necrosis factor transforming growth factor (TNF)-α, and tumor growth factor (TGF)-β), immunoglobulin (Ig) isotypes (IgG, IgM, and IgM), complement proteins (C3 and C4) with hemolytic activities (CH50 and AP50), and nitric oxide (NO) were evaluated in 65 patients, compared to 45 age- and sex-matched healthy controls. An insignificant decrease in 25(OH)D levels was observed in patients, compared to controls. In the patient group, elevated levels of IFN-γ, IL-17A, and IL-10 had a significant association with the serum levels of 25(OH)D, while the levels of TGF-β, IL-6, and TNF-α showed an insignificant association. The levels of IgG, C3, and NO also displayed such a statistically significant association with serum 25(OH)D levels. The AP50 levels which had significant difference were found to be not associated with serum 25(OH)D levels. Vitamin D might mediate a link between the innate and adaptive immune responses via the induction of Th1/Th17 polarization of cytokine responses and isotype regulation of antibody production, along with the maintenance of the capacity of the alternative complement pathway, in response to a UPEC infection. However, further studies are needed to validate the defined nature of the host immune response.
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Affiliation(s)
- Leila Pirdel
- Department of Medicine, Ardabil Branch, Islamic Azad University, Ardabil, Iran
| | - Manijeh Pirdel
- Department of Midwifery, Astara Branch, Islamic Azad University, Astara, Iran
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27
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Meza-Segura M, Zaidi MB, Vera-Ponce de León A, Moran-Garcia N, Martinez-Romero E, Nataro JP, Estrada-Garcia T. New Insights Into DAEC and EAEC Pathogenesis and Phylogeny. Front Cell Infect Microbiol 2020; 10:572951. [PMID: 33178627 PMCID: PMC7593697 DOI: 10.3389/fcimb.2020.572951] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Accepted: 09/09/2020] [Indexed: 11/13/2022] Open
Abstract
Diarrheagenic E. coli can be separated into six distinct pathotypes, with enteroaggregative (EAEC) and diffusely-adherent E. coli (DAEC) among the least characterized. To gain additional insights into these two pathotypes we performed whole genome sequencing of ten DAEC, nine EAEC strains, isolated from Mexican children with diarrhea, and one EAEC plus one commensal E. coli strains isolated from an adult with diarrhea and a healthy child, respectively. These genome sequences were compared to 85 E. coli genomes available in public databases. The EAEC and DAEC strains segregated into multiple different clades; however, six clades were heavily or exclusively comprised of EAEC and DAEC strains, suggesting a phylogenetic relationship between these two pathotypes. EAEC strains harbored the typical virulence factors under control of the activator AggR, but also several toxins, bacteriocins, and other virulence factors. DAEC strains harbored several iron-scavenging systems, toxins, adhesins, and complement resistance or Immune system evasion factors that suggest a pathogenic paradigm for this poorly understood pathotype. Several virulence factors for both EAEC and DAEC were associated with clinical presentations, not only suggesting the importance of these factors, but also potentially indicating opportunities for intervention. Our studies provide new insights into two distinct but related diarrheagenic organisms.
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Affiliation(s)
- Mario Meza-Segura
- Molecular Biomedicine Department, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Mexico City, Mexico
| | - Mussaret B Zaidi
- Infectious Diseases Research Unit, Hospital General O'Horan, Mérida, Mexico.,Department of Epidemiology and Biostatistics, Michigan State University, Lansing, MI, United States
| | | | - Nadia Moran-Garcia
- Molecular Biomedicine Department, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Mexico City, Mexico
| | | | - James P Nataro
- Department of Pediatrics, University of Virginia, Charlottesville, VI, United States
| | - Teresa Estrada-Garcia
- Molecular Biomedicine Department, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Mexico City, Mexico
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28
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Ohno M, Hasegawa M, Hayashi A, Caballero-Flores G, Alteri CJ, Lawley TD, Kamada N, Núñez G, Inohara N. Lipopolysaccharide O structure of adherent and invasive Escherichia coli regulates intestinal inflammation via complement C3. PLoS Pathog 2020; 16:e1008928. [PMID: 33027280 PMCID: PMC7571687 DOI: 10.1371/journal.ppat.1008928] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 10/19/2020] [Accepted: 08/25/2020] [Indexed: 12/28/2022] Open
Abstract
Gut dysbiosis associated with intestinal inflammation is characterized by the blooming of particular bacteria such as adherent-invasive E. coli (AIEC). However, the precise mechanisms by which AIEC impact on colitis remain largely unknown. Here we show that antibiotic-induced dysbiosis worsened chemically-induced colitis in IL-22-deficient mice, but not in wild-type mice. The increase in intestinal inflammation was associated with the expansion of E. coli strains with genetic and functional features of AIEC. These E. coli isolates exhibited high ability to out compete related bacteria via colicins and resistance to the host complement system in vitro. Mutation of wzy, the lipopolysaccharide O polymerase gene, rendered AIEC more sensitive to the complement system and more susceptible to engulfment and killing by phagocytes while retaining its ability to outcompete related bacteria in vitro. The wzy AIEC mutant showed impaired fitness to colonize the intestine under colitic conditions, but protected mice from chemically-induced colitis. Importantly, the ability of the wzy mutant to protect from colitis was blocked by depletion of complement C3 which was associated with impaired intestinal eradication of AIEC in colitic mice. These studies link surface lipopolysaccharide O-antigen structure to the regulation of colitic activity in commensal AIEC via interactions with the complement system.
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Affiliation(s)
- Masashi Ohno
- Department of Pathology, University of Michigan Medical School, Ann Arbor, Michigan, United States of America
- Department of Medicine, Shiga University of Medical Science, Otsu, Japan
| | - Mizuho Hasegawa
- Department of Pathology, University of Michigan Medical School, Ann Arbor, Michigan, United States of America
| | - Atsushi Hayashi
- Internal Medicine, University of Michigan Medical School, Ann Arbor, Michigan, United States of America
- Miyarisan Pharmaceutical Co., Ltd., Central Research Institute, Saitama, Japan
| | - Gustavo Caballero-Flores
- Rogel Cancer Center, University of Michigan Medical School, Ann Arbor, Michigan, United States of America
| | - Christopher J. Alteri
- Department of Natural Sciences, University of Michigan-Dearborn, Dearborn, Michigan, United States of America
| | - Trevor D. Lawley
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, United Kingdom
| | - Nobuhiko Kamada
- Internal Medicine, University of Michigan Medical School, Ann Arbor, Michigan, United States of America
| | - Gabriel Núñez
- Department of Pathology, University of Michigan Medical School, Ann Arbor, Michigan, United States of America
- Rogel Cancer Center, University of Michigan Medical School, Ann Arbor, Michigan, United States of America
| | - Naohiro Inohara
- Department of Pathology, University of Michigan Medical School, Ann Arbor, Michigan, United States of America
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29
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Tille A, Lehnert T, Zipfel PF, Figge MT. Quantification of Factor H Mediated Self vs. Non-self Discrimination by Mathematical Modeling. Front Immunol 2020; 11:1911. [PMID: 33013842 PMCID: PMC7493836 DOI: 10.3389/fimmu.2020.01911] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Accepted: 07/16/2020] [Indexed: 11/13/2022] Open
Abstract
The complement system is part of the innate immune system and plays an important role in the host defense against infectious pathogens. One of the main effects is the opsonization of foreign invaders and subsequent uptake by phagocytosis. Due to the continuous default basal level of active complement molecules, a tight regulation is required to protect the body's own cells (self cells) from opsonization and from complement damage. A major complement regulator is Factor H, which is recruited from the fluid phase and attaches to cell surfaces where it effectively controls complement activation. Besides self cells, pathogens also have the ability to bind Factor H; they can thus escape opsonization and phagocytosis causing severe infections. In order to advance our understanding of the opsonization process at a quantitative level, we developed a mathematical model for the dynamics of the complement system-termed DynaCoSys model-that is based on ordinary differential equations for cell surface-bound molecules and on partial differential equations for concentration profiles of the fluid phase molecules in the environment of cells. This hybrid differential equation approach allows to model the complement cascade focusing on the role of active C3b in the fluid phase and on the cell surface as well as on its inactivation on the cell surface. The DynaCoSys model enables us to quantitatively predict the conditions under which Factor H mediated complement evasion occurs. Furthermore, investigating the quantitative impact of model parameters by a sensitivity analysis, we identify the driving processes of complement activation and regulation in both the self and non-self regime. The two regimes are defined by a critical Factor H concentration on the cell surface and we use the model to investigate the differential impact of complement model parameters on this threshold value. The dynamic modeling on the surface of pathogens are further relevant to understand pathophysiological situations where Factor H mutants and defective Factor H binding to target surfaces results in pathophysiology such as renal and retinal disease. In the future, this DynaCoSys model will be extended to also enable evaluating treatment strategies of complement-related diseases.
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Affiliation(s)
- Alexander Tille
- Applied Systems Biology, Leibniz Institute for Natural Product Research and Infection Biology-Hans Knöll Institute, Jena, Germany.,Faculty of Biological Sciences, Institute of Microbiology, Friedrich-Schiller-University Jena, Jena, Germany
| | - Teresa Lehnert
- Applied Systems Biology, Leibniz Institute for Natural Product Research and Infection Biology-Hans Knöll Institute, Jena, Germany
| | - Peter F Zipfel
- Faculty of Biological Sciences, Institute of Microbiology, Friedrich-Schiller-University Jena, Jena, Germany.,Infection Biology, Leibniz Institute for Natural Product Research and Infection Biology-Hans Knöll Institute, Jena, Germany
| | - Marc Thilo Figge
- Applied Systems Biology, Leibniz Institute for Natural Product Research and Infection Biology-Hans Knöll Institute, Jena, Germany.,Faculty of Biological Sciences, Institute of Microbiology, Friedrich-Schiller-University Jena, Jena, Germany
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30
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Sharma S, Bhatnagar R, Gaur D. Complement Evasion Strategies of Human Pathogenic Bacteria. Indian J Microbiol 2020; 60:283-296. [PMID: 32655196 PMCID: PMC7329968 DOI: 10.1007/s12088-020-00872-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2019] [Accepted: 04/07/2020] [Indexed: 12/21/2022] Open
Abstract
Human pathogens need to overcome an elaborate network of host defense mechanisms in order to establish their infection, colonization, proliferation and eventual dissemination. The interaction of pathogens with different effector molecules of the immune system results in their neutralization and elimination from the host. The complement system is one such integral component of innate immunity that is critically involved in the early recognition and elimination of the pathogen. Hence, under this immune pressure, all virulent pathogens capable of inducing active infections have evolved immune evasive strategies that primarily target the complement system, which plays an essential and central role for host defense. Recent reports on several bacterial pathogens have elucidated the molecular mechanisms underlying complement evasion, inhibition of opsonic phagocytosis and cell lysis. This review aims to comprehensively summarize the recent findings on the various strategies adopted by pathogenic bacteria to escape complement-mediated clearance.
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Affiliation(s)
- Shikhar Sharma
- Laboratory of Malaria and Vaccine Research, School of Biotechnology, Jawaharlal Nehru University, New Mehrauli Road, New Delhi, 110067 India
| | - Rakesh Bhatnagar
- Molecular Biology and Genetic Engineering Laboratory, School of Biotechnology, Jawaharlal Nehru University, New Delhi, India
| | - Deepak Gaur
- Laboratory of Malaria and Vaccine Research, School of Biotechnology, Jawaharlal Nehru University, New Mehrauli Road, New Delhi, 110067 India
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31
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Bacterial killing by complement requires direct anchoring of membrane attack complex precursor C5b-7. PLoS Pathog 2020; 16:e1008606. [PMID: 32569291 PMCID: PMC7351214 DOI: 10.1371/journal.ppat.1008606] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Revised: 07/10/2020] [Accepted: 05/06/2020] [Indexed: 12/22/2022] Open
Abstract
An important effector function of the human complement system is to directly kill Gram-negative bacteria via Membrane Attack Complex (MAC) pores. MAC pores are assembled when surface-bound convertase enzymes convert C5 into C5b, which together with C6, C7, C8 and multiple copies of C9 forms a transmembrane pore that damages the bacterial cell envelope. Recently, we found that bacterial killing by MAC pores requires local conversion of C5 by surface-bound convertases. In this study we aimed to understand why local assembly of MAC pores is essential for bacterial killing. Here, we show that rapid interaction of C7 with C5b6 is required to form bactericidal MAC pores on Escherichia coli. Binding experiments with fluorescently labelled C6 show that C7 prevents release of C5b6 from the bacterial surface. Moreover, trypsin shaving experiments and atomic force microscopy revealed that this rapid interaction between C7 and C5b6 is crucial to efficiently anchor C5b-7 to the bacterial cell envelope and form complete MAC pores. Using complement-resistant clinical E. coli strains, we show that bacterial pathogens can prevent complement-dependent killing by interfering with the anchoring of C5b-7. While C5 convertase assembly was unaffected, these resistant strains blocked efficient anchoring of C5b-7 and thus prevented stable insertion of MAC pores into the bacterial cell envelope. Altogether, these findings provide basic molecular insights into how bactericidal MAC pores are assembled and how bacteria evade MAC-dependent killing. In this paper we focus on how the complement system, an essential part of the immune system, kills bacteria via so-called membrane attack complex (MAC) pores. The MAC is a large, ring-shaped pore that consists of five different proteins, which is assembled when the complement system is activated on the bacterial surface. Here, we aimed to better understand how MAC pores are assembled on Escherichia coli and how clinical E. coli strains resist killing by MAC pores. We uncover that rapid recruitment of one of the MAC proteins, namely C7, is crucial to efficiently anchor the MAC precursor to the bacterial surface and ensure killing of a variety of E. coli strains via MAC pores. Furthermore, we reveal that some clinical E. coli strains prevent this efficient anchoring of MAC precursors and thereby resist bacterial killing. These insights help us to better understand how the immune system kills bacteria and how pathogenic bacteria evade this.
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Virulence gene transcription, phylogroups, and antibiotic resistance of cervico-vaginal pathogenic E. coli in Mexico. PLoS One 2020; 15:e0234730. [PMID: 32569308 PMCID: PMC7307731 DOI: 10.1371/journal.pone.0234730] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Accepted: 06/01/2020] [Indexed: 11/19/2022] Open
Abstract
The pathogenicity of Escherichia coli strains that cause cervico-vaginal infections (CVI) is due to the presence of several virulence genes. The objective of this study was to define the variability regarding the genotype of antibiotic resistance, the transcription profiles of virulence genes after in vitro infection of the vaginal cell line A431 and the phylogroup composition of a group of cervico-vaginal E. coli strains (CVEC). A total of 200 E. coli strains isolated from Mexican women with CVI from two medical units of the Mexican Institute of Social Security were analysed. E. coli strains and antibiotic resistance genes were identified using conventional polymerase chain reaction (PCR), and phylogroups were identified using multiplex PCR. Virulence gene transcription was measured through reverse-transcriptase real-time PCR after infection of the vaginal cell line A431. The most common antibiotic resistance genes among the CVEC strains were aac(3)II, TEM, dfrA1, sul1, and qnrA. The predominant phylogroup was B2. The genes most frequently transcribed in these strains were fimH, papC, irp2, iroN, kpsMTII, cnf1, and ompT, mainly in CVEC strains isolated from chronic and occasional vaginal infections. The strains showed a large diversity of transcription of the virulence genes phenotype and antibiotic resistance genotype, especially in the strains of phylogroups, B2, A, and D. The strains formed 2 large clusters, which contained several subclusters. The genetic diversity of CVEC strains was high. These strains have a large number of transcription patterns of virulence genes, and one-third of them carry three to seven antibiotic resistance genes.
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Moraes CTP, Longo J, Silva LB, Pimenta DC, Carvalho E, Morone MSLC, da Rós N, Serrano SMT, Santos ACM, Piazza RMF, Barbosa AS, Elias WP. Surface Protein Dispersin of Enteroaggregative Escherichia coli Binds Plasminogen That Is Converted Into Active Plasmin. Front Microbiol 2020; 11:1222. [PMID: 32625178 PMCID: PMC7315649 DOI: 10.3389/fmicb.2020.01222] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2019] [Accepted: 05/14/2020] [Indexed: 01/24/2023] Open
Abstract
Dispersin is a 10.2 kDa-immunogenic protein secreted by enteroaggregative Escherichia coli (EAEC). In the prototypical EAEC strain 042, dispersin is non-covalently bound to the outer membrane, assisting dispersion across the intestinal mucosa by overcoming electrostatic attraction between the AAF/II fimbriae and the bacterial surface. Also, dispersin facilitates penetration of the intestinal mucus layer. Initially characterized in EAEC, dispersin has been detected in other E. coli pathotypes, including those isolated from extraintestinal sites. In this study we investigated the binding capacity of purified dispersin to extracellular matrix (ECM), since dispersin is exposed on the bacterial surface and is involved in intestinal colonization. Binding to plasminogen was also investigated due to the presence of conserved carboxy-terminal lysine residues in dispersin sequences, which are involved in plasminogen binding in several bacterial proteins. Moreover, some E. coli components can interact with this host protease, as well as with tissue plasminogen activator, leading to plasmin production. Recombinant dispersin was produced and used in binding assays with ECM molecules and coagulation cascade compounds. Purified dispersin bound specifically to laminin and plasminogen. Interaction with plasminogen occurred in a dose-dependent and saturable manner. In the presence of plasminogen activator, bound plasminogen was converted into plasmin, its active form, leading to fibrinogen and vitronectin cleavage. A collection of E. coli strains isolated from human bacteremia was screened for the presence of aap, the dispersin-encoding gene. Eight aap-positive strains were detected and dispersin production could be observed in four of them. Our data describe new attributes for dispersin and points out to possible roles in mechanisms of tissue adhesion and dissemination, considering the binding capacity to laminin, and the generation of dispersin-bound plasmin(ogen), which may facilitate E. coli spread from the colonization site to other tissues and organs. The cleavage of fibrinogen in the bloodstream, may also contribute to the pathogenesis of sepsis caused by dispersin-producing E. coli.
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Affiliation(s)
| | - Jonathan Longo
- Laboratory of Bacteriology, Butantan Institute, São Paulo, Brazil
| | - Ludmila B Silva
- Laboratory of Bacteriology, Butantan Institute, São Paulo, Brazil
| | - Daniel C Pimenta
- Laboratory of Biochemistry and Biophysics, Butantan Institute, São Paulo, Brazil
| | - Eneas Carvalho
- Laboratory of Bacteriology, Butantan Institute, São Paulo, Brazil
| | - Mariana S L C Morone
- Laboratory of Applied Toxinology - Center of Toxins, Immune-Response and Cell Signaling (CeTICS), Butantan Institute, São Paulo, Brazil
| | - Nancy da Rós
- Laboratory of Applied Toxinology - Center of Toxins, Immune-Response and Cell Signaling (CeTICS), Butantan Institute, São Paulo, Brazil
| | - Solange M T Serrano
- Laboratory of Applied Toxinology - Center of Toxins, Immune-Response and Cell Signaling (CeTICS), Butantan Institute, São Paulo, Brazil
| | - Ana Carolina M Santos
- Department of Microbiology, Immunology and Parasitology, Federal University of São Paulo, São Paulo, Brazil
| | | | - Angela S Barbosa
- Laboratory of Bacteriology, Butantan Institute, São Paulo, Brazil
| | - Waldir P Elias
- Laboratory of Bacteriology, Butantan Institute, São Paulo, Brazil
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Salamon H, Nissim-Eliraz E, Ardronai O, Nissan I, Shpigel NY. The role of O-polysaccharide chain and complement resistance of Escherichia coli in mammary virulence. Vet Res 2020; 51:77. [PMID: 32539761 PMCID: PMC7294653 DOI: 10.1186/s13567-020-00804-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Accepted: 05/27/2020] [Indexed: 12/19/2022] Open
Abstract
Mastitis, inflammation of the mammary gland, is a common disease of dairy animals. The disease is caused by bacterial infection ascending through the teat canal and mammary pathogenic Escherichia coli (MPEC) are common etiology. In the first phase of infection, virulence mechanisms, designated as niche factors, enable MPEC bacteria to resist innate antimicrobial mechanisms, replicate in milk, and to colonize the mammary gland. Next, massive replication of colonizing bacteria culminates in a large biomass of microbe-associated molecular patterns (MAMPs) recognized by pattern recognition receptors (PRRs) such as toll-like receptors (TLRs) mediating inflammatory signaling in mammary alveolar epithelial cells (MAEs) and macrophages. Bacterial lipopolysaccharides (LPSs), the prototypical class of MAMPs are sufficient to elicit mammary inflammation mediated by TLR4 signaling and activation of nuclear factor kB (NF-kB), the master regulator of inflammation. Using in vivo mastitis model, in low and high complements mice, and in vitro NF-kB luminescence reporter system in MAEs, we have found that the smooth configuration of LPS O-polysaccharides in MPEC enables the colonizing organisms to evade the host immune response by reducing inflammatory response and conferring resistance to complement. Screening a collection of MPEC field strains, we also found that all strains were complement resistant and 94% (45/48) were smooth. These results indicate that the structure of LPS O-polysaccharides chain is important for the pathogenesis of MPEC mastitis and provides protection against complement-mediated killing. Furthermore, we demonstrate a role for complement, a key component of innate immunity, in host-microbe interactions of the mammary gland.
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Affiliation(s)
- Hagit Salamon
- The Koret School of Veterinary Medicine, Hebrew University of Jerusalem, POB 12, 76100, Rehovot, Israel
| | - Einat Nissim-Eliraz
- The Koret School of Veterinary Medicine, Hebrew University of Jerusalem, POB 12, 76100, Rehovot, Israel
| | - Oded Ardronai
- The Koret School of Veterinary Medicine, Hebrew University of Jerusalem, POB 12, 76100, Rehovot, Israel
| | - Israel Nissan
- The Koret School of Veterinary Medicine, Hebrew University of Jerusalem, POB 12, 76100, Rehovot, Israel
| | - Nahum Y Shpigel
- The Koret School of Veterinary Medicine, Hebrew University of Jerusalem, POB 12, 76100, Rehovot, Israel.
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Kumar D, Romero Y, Schuck KN, Smalley H, Subedi B, Fleming SD. Drivers and regulators of humoral innate immune responses to infection and cancer. Mol Immunol 2020; 121:99-110. [PMID: 32199212 PMCID: PMC7207242 DOI: 10.1016/j.molimm.2020.03.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2019] [Revised: 03/06/2020] [Accepted: 03/09/2020] [Indexed: 12/21/2022]
Abstract
The complement cascade consists of cell bound and serum proteins acting together to protect the host from pathogens, remove cancerous cells and effectively links innate and adaptive immune responses. Despite its usefulness in microbial neutralization and clearance of cancerous cells, excessive complement activation causes an immune imbalance and tissue damage in the host. Hence, a series of complement regulatory proteins present at a higher concentration in blood plasma and on cell surfaces tightly regulate the cascade. The complement cascade can be initiated by B-1 B cell production of natural antibodies. Natural antibodies arise spontaneously without any known exogenous antigenic or microbial stimulus and protect against invading pathogens, clear apoptotic cells, provide tissue homeostasis, and modulate adaptive immune functions. Natural IgM antibodies recognize microbial and cancer antigens and serve as an activator of complement mediated lysis. This review will discuss advances in complement activation and regulation in bacterial and viral infections, and cancer. We will also explore the crosstalk of natural antibodies with bacterial populations and cancer.
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MESH Headings
- Antigens, Bacterial/immunology
- Antigens, Bacterial/metabolism
- Antigens, Neoplasm/immunology
- Antigens, Neoplasm/metabolism
- Antigens, Viral/immunology
- Antigens, Viral/metabolism
- Apoptosis/immunology
- B-Lymphocytes/immunology
- B-Lymphocytes/metabolism
- Bacterial Infections/immunology
- Complement Activation
- Complement System Proteins/immunology
- Complement System Proteins/metabolism
- Humans
- Immunity, Humoral
- Immunity, Innate
- Immunoglobulin M/immunology
- Immunoglobulin M/metabolism
- Neoplasms/immunology
- Receptors, Complement/immunology
- Receptors, Complement/metabolism
- Tumor Escape
- Virus Diseases/immunology
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Affiliation(s)
- Deepak Kumar
- Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS, USA
| | - Yeni Romero
- Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, KS, USA
| | - Kaitlynn N Schuck
- Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS, USA
| | - Haley Smalley
- Division of Biology, Kansas State University, Manhattan, KS, USA
| | - Bibek Subedi
- Division of Biology, Kansas State University, Manhattan, KS, USA
| | - Sherry D Fleming
- Division of Biology, Kansas State University, Manhattan, KS, USA.
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Heimes A, Brodhagen J, Weikard R, Seyfert HM, Becker D, Meyerholz MM, Petzl W, Zerbe H, Hoedemaker M, Rohmeier L, Schuberth HJ, Schmicke M, Engelmann S, Kühn C. Hepatic Transcriptome Analysis Identifies Divergent Pathogen-Specific Targeting-Strategies to Modulate the Innate Immune System in Response to Intramammary Infection. Front Immunol 2020; 11:715. [PMID: 32411137 PMCID: PMC7202451 DOI: 10.3389/fimmu.2020.00715] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Accepted: 03/30/2020] [Indexed: 12/22/2022] Open
Abstract
Mastitis is one of the major risks for public health and animal welfare in the dairy industry. Two of the most important pathogens to cause mastitis in dairy cattle are Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli). While S. aureus generally induces a chronic and subclinical mastitis, E. coli is an important etiological pathogen resulting in an acute and clinical mastitis. The liver plays a central role in both, the metabolic and inflammatory physiology of the dairy cow, which is particularly challenged in the early lactation due to high metabolic and immunological demands. In the current study, we challenged the mammary glands of Holstein cows with S. aureus or E. coli, respectively, mimicking an early lactation infection. We compared the animals' liver transcriptomes with those of untreated controls to investigate the hepatic response of the individuals. Both, S. aureus and E. coli elicited systemic effects on the host after intramammary challenge and seemed to use pathogen-specific targeting strategies to bypass the innate immune system. The most striking result of our study is that we demonstrate for the first time that S. aureus intramammary challenge causes an immune response beyond the original local site of the mastitis. We found that in the peripheral liver tissue defined biological pathways are switched on in a coordinated manner to balance the immune response in the entire organism. TGFB1 signaling plays a crucial role in this context. Important pathways involving actin and integrin, key components of the cytoskeleton, were downregulated in the liver of S. aureus infected cows. In the hepatic transcriptome of E. coli infected cows, important components of the complement system were significantly lower expressed compared to the control cows. Notably, while S. aureus inhibits the cell signaling by Rho GTPases in the liver, E. coli switches the complement system off. Also, metabolic hepatic pathways (e.g., lipid metabolism) are affected after mammary gland challenge, demonstrating that the liver restricts metabolic tasks in favor of the predominant immune response after infection. Our results provide new insights for the infection-induced modifications of the dairy cow's hepatic transcriptome following mastitis.
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Affiliation(s)
- Annika Heimes
- Leibniz Institute for Farm Animal Biology (FBN), Institute of Genome Biology, Dummerstorf, Germany
| | - Johanna Brodhagen
- Leibniz Institute for Farm Animal Biology (FBN), Institute of Genome Biology, Dummerstorf, Germany
| | - Rosemarie Weikard
- Leibniz Institute for Farm Animal Biology (FBN), Institute of Genome Biology, Dummerstorf, Germany
| | - Hans-Martin Seyfert
- Leibniz Institute for Farm Animal Biology (FBN), Institute of Genome Biology, Dummerstorf, Germany
| | - Doreen Becker
- Leibniz Institute for Farm Animal Biology (FBN), Institute of Genome Biology, Dummerstorf, Germany
| | - Marie M Meyerholz
- Clinic for Ruminants with Ambulatory and Herd Health Services, Centre for Clinical Veterinary Medicine, Ludwig-Maximilians-University Munich, Oberschleißheim, Germany
| | - Wolfram Petzl
- Clinic for Ruminants with Ambulatory and Herd Health Services, Centre for Clinical Veterinary Medicine, Ludwig-Maximilians-University Munich, Oberschleißheim, Germany
| | - Holm Zerbe
- Clinic for Ruminants with Ambulatory and Herd Health Services, Centre for Clinical Veterinary Medicine, Ludwig-Maximilians-University Munich, Oberschleißheim, Germany
| | - Martina Hoedemaker
- Clinic for Cattle, University of Veterinary Medicine Hanover, Hanover, Germany
| | - Laura Rohmeier
- Clinic for Ruminants with Ambulatory and Herd Health Services, Centre for Clinical Veterinary Medicine, Ludwig-Maximilians-University Munich, Oberschleißheim, Germany.,Clinic for Swine, Small Ruminants, Forensic Medicine and Ambulatory Service, University of Veterinary Medicine Hanover, Hanover, Germany
| | | | - Marion Schmicke
- Faculty of Natural Sciences III, Martin-Luther Universität Halle-Wittenberg, Halle, Germany
| | - Susanne Engelmann
- Technical University Braunschweig, Institute for Microbiology, Brunswick, Germany.,Helmholtz Centre for Infection Research, Microbial Proteomics, Brunswick, Germany
| | - Christa Kühn
- Leibniz Institute for Farm Animal Biology (FBN), Institute of Genome Biology, Dummerstorf, Germany.,Agricultural and Environmental Faculty, University Rostock, Rostock, Germany
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Comparative Genomic Analysis Provides Insights into the Phylogeny, Resistome, Virulome, and Host Adaptation in the Genus Ewingella. Pathogens 2020; 9:pathogens9050330. [PMID: 32354059 PMCID: PMC7281767 DOI: 10.3390/pathogens9050330] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 04/20/2020] [Accepted: 04/22/2020] [Indexed: 12/18/2022] Open
Abstract
Ewingella americana is a cosmopolitan bacterial pathogen that has been isolated from many hosts. Here, we sequenced a high-quality genome of E. americana B6-1 isolated from Flammulina filiformis, an important cultivated mushroom, performed a comparative genomic analysis with four other E. americana strains from various origins, and tested the susceptibility of B6-1 to antibiotics. The genome size, predicted genes, and GC (guanine-cytosine) content of B6-1 was 4.67 Mb, 4301, and 53.80%, respectively. The origin of the strains did not significantly affect the phylogeny, but mobile genetic elements shaped the evolution of the genus Ewingella. The strains encoded a set of common genes for type secretion, virulence effectors, CAZymes, and toxins required for pathogenicity in all hosts. They also had antibiotic resistance, pigments to suppress or evade host defense responses, as well as genes for adaptation to different environmental conditions, including temperature, oxidation, and nutrients. These findings provide a better understanding of the virulence, antibiotic resistance, and host adaptation strategies of Ewingella, and they also contribute to the development of effective control strategies.
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Lindholm M, Metsäniitty M, Granström E, Oscarsson J. Outer membrane vesicle-mediated serum protection in Aggregatibacter actinomycetemcomitans. J Oral Microbiol 2020; 12:1747857. [PMID: 32363008 PMCID: PMC7178816 DOI: 10.1080/20002297.2020.1747857] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Revised: 03/16/2020] [Accepted: 03/18/2020] [Indexed: 01/23/2023] Open
Abstract
Aggregatibacter actinomycetemcomitans belongs to the HACEK group of fastidious Gram-negative organisms, a recognized cause of infective endocarditis. A. actinomycetemcomitans is also implicated in periodontitis, with rapid progress in adolescents. We recently demonstrated that the major outer membrane protein, OmpA1 was critical for serum survival of the A. actinomycetemcomitans serotype a model strain, D7SS, and that the paralogue, OmpA2 could operate as a functional homologue to OmpA1 in mediating serum resistance. In the present work, an essentially serum-sensitive ompA1 ompA2 double mutant A. actinomycetemcomitans strain derivative was exploited to elucidate if A. actinomycetemcomitans OMVs can contribute to bacterial serum resistance. Indeed, supplementation of OMVs resulted in a dose-dependent increase of the survival of the serum-sensitive strain in incubations in 50% normal human serum (NHS). Whereas neither OmpA1 nor OmpA2 was required for the OMV-mediated serum protection, OMVs and LPS from an A. actinomycetemcomitans strain lacking the LPS O-antigen polysaccharide part were significantly impaired in protecting D7SS ompA1 ompA2. Our results using a complement system screen assay support a model where A. actinomycetemcomitans OMVs can act as a decoy, which can trigger complement activation in an LPS-dependent manner, and consume complement components to protect serum-susceptible bacterial cells.
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Affiliation(s)
- Mark Lindholm
- Oral Microbiology, Department of Odontology, Umeå University, Umeå, Sweden
| | - Marjut Metsäniitty
- Oral Microbiology, Department of Odontology, Umeå University, Umeå, Sweden
| | | | - Jan Oscarsson
- Oral Microbiology, Department of Odontology, Umeå University, Umeå, Sweden
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Nagy ZA, Szakács D, Boros E, Héja D, Vígh E, Sándor N, Józsi M, Oroszlán G, Dobó J, Gál P, Pál G. Ecotin, a microbial inhibitor of serine proteases, blocks multiple complement dependent and independent microbicidal activities of human serum. PLoS Pathog 2019; 15:e1008232. [PMID: 31860690 PMCID: PMC6944378 DOI: 10.1371/journal.ppat.1008232] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Revised: 01/06/2020] [Accepted: 11/21/2019] [Indexed: 12/20/2022] Open
Abstract
Ecotin is a serine protease inhibitor produced by hundreds of microbial species, including pathogens. Here we show, that ecotin orthologs from Escherichia coli, Yersinia pestis, Pseudomonas aeruginosa and Leishmania major are potent inhibitors of MASP-1 and MASP-2, the two key activator proteases of the complement lectin pathway. Factor D is the key activator protease of another complement activation route, the alternative pathway. We show that ecotin inhibits MASP-3, which is the sole factor D activator in resting human blood. In pathway-specific ELISA tests, we found that all ecotin orthologs are potent lectin pathway inhibitors, and at high concentration, they block the alternative pathway as well. In flow cytometry experiments, we compared the extent of complement-mediated opsonization and lysis of wild-type and ecotin-knockout variants of two E. coli strains carrying different surface lipopolysaccharides. We show, that endogenous ecotin provides significant protections against these microbicidal activities for both bacteria. By using pathway specific complement inhibitors, we detected classical-, lectin- and alternative pathway-driven complement attack from normal serum, with the relative contributions of the activation routes depending on the lipopolysaccharide type. Moreover, in cell proliferation experiments we observed an additional, complement-unrelated antimicrobial activity exerted by heat-inactivated serum. While ecotin-knockout cells are highly vulnerable to these activities, endogenous ecotin of wild-type bacteria provides complete protection against the lectin pathway-related and the complement-unrelated attack, and partial protection against the alternative pathway-related damage. In all, ecotin emerges as a potent, versatile self-defense tool that blocks multiple antimicrobial activities of the serum. These findings suggest that ecotin might be a relevant antimicrobial drug target. Bloodstream infections are major cause of morbidity and mortality in many countries around the globe. As the number of multi-drug resistant pathogenic strains is growing, it is urgent to identify their virulence factors and unveil the corresponding mechanisms of action that enable the pathogen to avoid potent immune response. A microbial inhibitor of serine proteases, ecotin was previously implicated in protecting various pathogenic bacteria and eukaryotic Leishmania species against the host immune system by inhibiting leukocyte elastase. However, the interaction of ecotin with the complement system, which provides a first line defense against pathogens, remained unexplored. We found that ecotin blocks activation of the complement lectin pathway by inhibiting its key activator enzymes, MASP-1 and MASP-2. Furthermore, by inhibiting MASP-3, ecotin also disrupts a fundamental link between the lectin- and the alternative pathways. We provide evidence that E. coli cells devoid of ecotin are extremely vulnerable to complement-mediated lysis and they are also potently killed by some complement-independent antimicrobial factors of human serum. These findings could explain the observations of other research groups reporting that ecotin is crucial for the survival of pathogenic microbes in the host. Our results therefore also highlight ecotin as a potential target of future antimicrobial therapies.
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Affiliation(s)
- Zoltán Attila Nagy
- Department of Biochemistry, ELTE, Eötvös Loránd University, Budapest, Hungary
| | - Dávid Szakács
- Department of Biochemistry, ELTE, Eötvös Loránd University, Budapest, Hungary
| | - Eszter Boros
- Department of Biochemistry, ELTE, Eötvös Loránd University, Budapest, Hungary
| | - Dávid Héja
- Department of Biochemistry, ELTE, Eötvös Loránd University, Budapest, Hungary
- Department of Nephrology, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America
| | - Eszter Vígh
- Department of Biochemistry, ELTE, Eötvös Loránd University, Budapest, Hungary
| | - Noémi Sándor
- Department of Immunology, ELTE, Eötvös Loránd University, Budapest, Hungary
| | - Mihály Józsi
- Department of Immunology, ELTE, Eötvös Loránd University, Budapest, Hungary
| | - Gábor Oroszlán
- Institute of Enzymology, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Budapest, Hungary
| | - József Dobó
- Institute of Enzymology, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Budapest, Hungary
| | - Péter Gál
- Institute of Enzymology, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Budapest, Hungary
| | - Gábor Pál
- Department of Biochemistry, ELTE, Eötvös Loránd University, Budapest, Hungary
- * E-mail:
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Patro LPP, Rathinavelan T. Targeting the Sugary Armor of Klebsiella Species. Front Cell Infect Microbiol 2019; 9:367. [PMID: 31781512 PMCID: PMC6856556 DOI: 10.3389/fcimb.2019.00367] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2019] [Accepted: 10/09/2019] [Indexed: 12/25/2022] Open
Abstract
The emergence of multidrug-resistant strains of Gram-negative Klebsiella species is an urgent global threat. The World Health Organization has listed Klebsiella pneumoniae as one of the global priority pathogens in critical need of next-generation antibiotics. Compared to other Gram-negative pathogens, K. pneumoniae accumulates a greater diversity of antimicrobial-resistant genes at a higher frequency. The evolution of a hypervirulent phenotype of K. pneumoniae is yet another concern. It has a broad ecological distribution affecting humans, agricultural animals, plants, and aquatic animals. Extracellular polysaccharides of Klebsiella, such as lipopolysaccharides, capsular polysaccharides, and exopolysaccharides, play crucial roles in conferring resistance against the host immune response, as well as in colonization, surface adhesion, and for protection against antibiotics and bacteriophages. These extracellular polysaccharides are major virulent determinants and are highly divergent with respect to their antigenic properties. Wzx/Wzy-, ABC-, and synthase-dependent proteinaceous nano-machineries are involved in the biosynthesis, transport, and cell surface expression of these sugar molecules. Although the proteins involved in the biosynthesis and surface expression of these sugar molecules represent potential drug targets, variation in the amino acid sequences of some of these proteins, in combination with diversity in their sugar composition, poses a major challenge to the design of a universal drug for Klebsiella infections. This review discusses the challenges in universal Klebsiella vaccine and drug development from the perspective of antigen sugar compositions and the proteins involved in extracellular antigen transport.
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Ferro P, Vaz-Moreira I, Manaia CM. Betaproteobacteria are predominant in drinking water: are there reasons for concern? Crit Rev Microbiol 2019; 45:649-667. [PMID: 31686572 DOI: 10.1080/1040841x.2019.1680602] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Betaproteobacteria include some of the most abundant and ubiquitous bacterial genera that can be found in drinking water, including mineral water. The combination of physiology and ecology traits place some Betaproteobacteria in the list of potential, yet sometimes neglected, opportunistic pathogens that can be transmitted by water or aqueous solutions. Indeed, some drinking water Betaproteobacteria with intrinsic and sometimes acquired antibiotic resistance, harbouring virulence factors and often found in biofilm structures, can persist after water disinfection and reach the consumer. This literature review summarises and discusses the current knowledge about the occurrence and implications of Betaproteobacteria in drinking water. Although the sparse knowledge on the ecology and physiology of Betaproteobacteria thriving in tap or bottled natural mineral/spring drinking water (DW) is an evidence of this review, it is demonstrated that DW holds a high diversity of Betaproteobacteria, whose presence may not be innocuous. Frequently belonging to genera also found in humans, DW Betaproteobacteria are ubiquitous in different habitats, have the potential to resist antibiotics either due to intrinsic or acquired mechanisms, and hold different virulence factors. The combination of these factors places DW Betaproteobacteria in the list of candidates of emerging opportunistic pathogens. Improved bacterial identification of clinical isolates associated with opportunistic infections and additional genomic and physiological studies may contribute to elucidate the potential impact of these bacteria.
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Affiliation(s)
- Pompeyo Ferro
- Universidade Católica Portuguesa, CBQF - Centro de Biotecnologia e Química Fina - Laboratório Associado, Escola Superior de Biotecnologia, Porto, Portugal
| | - Ivone Vaz-Moreira
- Universidade Católica Portuguesa, CBQF - Centro de Biotecnologia e Química Fina - Laboratório Associado, Escola Superior de Biotecnologia, Porto, Portugal
| | - Célia M Manaia
- Universidade Católica Portuguesa, CBQF - Centro de Biotecnologia e Química Fina - Laboratório Associado, Escola Superior de Biotecnologia, Porto, Portugal
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Chen DD, Li JH, Yao YY, Zhang YA. Aeromonas hydrophila suppresses complement pathways via degradation of complement C3 in bony fish by metalloprotease. FISH & SHELLFISH IMMUNOLOGY 2019; 94:739-745. [PMID: 31561026 DOI: 10.1016/j.fsi.2019.09.057] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Revised: 09/18/2019] [Accepted: 09/23/2019] [Indexed: 06/10/2023]
Abstract
Aeromonas hydrophila is a pathogen that causes high mortality in the grass carp. The complement system, as a frontline defence of innate immunity, plays an important role in the immune response against pathogens. However, the immunity evasion mechanism of A. hydrophila against the complement system of grass carp remains unclear. In this study, we described an additional mechanism used by A. hydrophila GD18 to evade the complement system and survive in grass carp serum. First, A. hydrophila evaded the bactericidal activity of grass carp serum. Second, the haemolytic activity assays showed that A. hydrophila obviously suppressed the alternative pathway, which depended on preventing the formation or disabling the function of the membrane-attack complex (MAC). Further research indicated that A. hydrophila targeted complement C3, the central component of the three complement pathways, and degraded it in the grass carp serum, leading to the inhibition of the complement pathways, which resulted in the serum-resistance of A. hydrophila. Furthermore, cleavage analyses showed that extracellular proteases (ECPases) of A. hydrophila efficiently cleaved purified C3 as well as C3 in grass carp serum. Finally, protease inhibitor studies and mass spectrum analysis identified the secreted metalloprotease elastase (AhE), which was present in large amounts in crude ECPases, as the central molecule responsible for C3 cleavage. Compared to wild strain GD18, the AhE knockout, Δahe was dramatically reduced in the ability of serum resistance. Our findings suggested that A. hydrophila escaped serum-killing by suppressing the complement pathways via the degradation of complement C3 in bony fish, which was related to secreted metalloproteases.
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Affiliation(s)
- Dan-Dan Chen
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China; Key Laboratory of Aquaculture Disease Control, Ministry of Agriculture, Wuhan, China
| | - Ji-Hong Li
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China; University of Chinese Academy of Sciences, Beijing, China
| | - Yuan-Yuan Yao
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China; University of Chinese Academy of Sciences, Beijing, China
| | - Yong-An Zhang
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China; State Key Laboratory of Agricultural Microbiology, College of Fisheries, Huazhong Agricultural University, Wuhan, China.
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Geisinger E, Huo W, Hernandez-Bird J, Isberg RR. Acinetobacter baumannii: Envelope Determinants That Control Drug Resistance, Virulence, and Surface Variability. Annu Rev Microbiol 2019; 73:481-506. [DOI: 10.1146/annurev-micro-020518-115714] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Acinetobacter baumannii has emerged as an important nosocomial pathogen, particularly for patients in intensive care units and with invasive indwelling devices. The most recent clinical isolates are resistant to several classes of clinically important antibiotics, greatly restricting the ability to effectively treat critically ill patients. The bacterial envelope is an important driver of A. baumannii disease, both at the level of battling against antibiotic therapy and at the level of protecting from host innate immune function. This review provides a comprehensive overview of key features of the envelope that interface with both the host and antimicrobial therapies. Carbohydrate structures that contribute to protecting from the host are detailed, and mutations that alter these structures, resulting in increased antimicrobial resistance, are explored. In addition, protein complexes involved in both intermicrobial and host-microbe interactions are described. Finally we discuss regulatory mechanisms that control the nature of the cell envelope and its impact on host innate immune function.
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Affiliation(s)
- Edward Geisinger
- Department of Biology, Northeastern University, Boston, Massachusetts 02115, USA
| | - Wenwen Huo
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts 02111, USA
| | - Juan Hernandez-Bird
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts 02111, USA
| | - Ralph R. Isberg
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts 02111, USA
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Oscarsson J, Claesson R, Lindholm M, Höglund Åberg C, Johansson A. Tools of Aggregatibacter actinomycetemcomitans to Evade the Host Response. J Clin Med 2019; 8:E1079. [PMID: 31336649 PMCID: PMC6678183 DOI: 10.3390/jcm8071079] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Revised: 07/08/2019] [Accepted: 07/18/2019] [Indexed: 02/06/2023] Open
Abstract
Periodontitis is an infection-induced inflammatory disease that affects the tooth supporting tissues, i.e., bone and connective tissues. The initiation and progression of this disease depend on dysbiotic ecological changes in the oral microbiome, thereby affecting the severity of disease through multiple immune-inflammatory responses. Aggregatibacter actinomycetemcomitans is a facultative anaerobic Gram-negative bacterium associated with such cellular and molecular mechanisms associated with the pathogenesis of periodontitis. In the present review, we outline virulence mechanisms that help the bacterium to escape the host response. These properties include invasiveness, secretion of exotoxins, serum resistance, and release of outer membrane vesicles. Virulence properties of A. actinomycetemcomitans that can contribute to treatment resistance in the infected individuals and upon translocation to the circulation, also induce pathogenic mechanisms associated with several systemic diseases.
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Affiliation(s)
- Jan Oscarsson
- Department of Odontology, Oral Microbiology, Umeå University, S-90187 Umeå, Sweden
| | - Rolf Claesson
- Department of Odontology, Oral Microbiology, Umeå University, S-90187 Umeå, Sweden
| | - Mark Lindholm
- Department of Odontology, Oral Microbiology, Umeå University, S-90187 Umeå, Sweden
| | - Carola Höglund Åberg
- Department of Odontology, Molecular Periodontology, Umeå University, S-901 87 Umeå, Sweden
| | - Anders Johansson
- Department of Odontology, Molecular Periodontology, Umeå University, S-901 87 Umeå, Sweden.
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Etienne-Mesmin L, Chassaing B, Desvaux M, De Paepe K, Gresse R, Sauvaitre T, Forano E, de Wiele TV, Schüller S, Juge N, Blanquet-Diot S. Experimental models to study intestinal microbes–mucus interactions in health and disease. FEMS Microbiol Rev 2019; 43:457-489. [DOI: 10.1093/femsre/fuz013] [Citation(s) in RCA: 71] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2019] [Accepted: 05/31/2019] [Indexed: 02/06/2023] Open
Abstract
ABSTRACT
A close symbiotic relationship exists between the intestinal microbiota and its host. A critical component of gut homeostasis is the presence of a mucus layer covering the gastrointestinal tract. Mucus is a viscoelastic gel at the interface between the luminal content and the host tissue that provides a habitat to the gut microbiota and protects the intestinal epithelium. The review starts by setting up the biological context underpinning the need for experimental models to study gut bacteria-mucus interactions in the digestive environment. We provide an overview of the structure and function of intestinal mucus and mucins, their interactions with intestinal bacteria (including commensal, probiotics and pathogenic microorganisms) and their role in modulating health and disease states. We then describe the characteristics and potentials of experimental models currently available to study the mechanisms underpinning the interaction of mucus with gut microbes, including in vitro, ex vivo and in vivo models. We then discuss the limitations and challenges facing this field of research.
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Affiliation(s)
- Lucie Etienne-Mesmin
- Université Clermont Auvergne, INRA, MEDIS, 28 Place Henri Dunant, 63000 Clermont-Ferrand, France
| | - Benoit Chassaing
- Neuroscience Institute, Georgia State University, 100 Piedmont Ave SE, Atlanta, GA 30303 , USA
- Institute for Biomedical Sciences, Georgia State University, 100 Piedmont Ave, Atlanta, GA 30303 , USA
| | - Mickaël Desvaux
- Université Clermont Auvergne, INRA, MEDIS, 28 Place Henri Dunant, 63000 Clermont-Ferrand, France
| | - Kim De Paepe
- Center for Microbial Ecology and Technology (CMET), Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000 Ghent, Belgium
| | - Raphaële Gresse
- Université Clermont Auvergne, INRA, MEDIS, 28 Place Henri Dunant, 63000 Clermont-Ferrand, France
| | - Thomas Sauvaitre
- Université Clermont Auvergne, INRA, MEDIS, 28 Place Henri Dunant, 63000 Clermont-Ferrand, France
| | - Evelyne Forano
- Université Clermont Auvergne, INRA, MEDIS, 28 Place Henri Dunant, 63000 Clermont-Ferrand, France
| | - Tom Van de Wiele
- Center for Microbial Ecology and Technology (CMET), Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000 Ghent, Belgium
| | - Stephanie Schüller
- Norwich Medical School, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, United Kingdom
- Quadram Institute Bioscience, Norwich Research Park, Norwich NR7UQ, United Kingdom
| | - Nathalie Juge
- Quadram Institute Bioscience, Norwich Research Park, Norwich NR7UQ, United Kingdom
| | - Stéphanie Blanquet-Diot
- Université Clermont Auvergne, INRA, MEDIS, 28 Place Henri Dunant, 63000 Clermont-Ferrand, France
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Bánki Z, Krabbendam L, Klaver D, Leng T, Kruis S, Mehta H, Müllauer B, Orth-Höller D, Stoiber H, Willberg CB, Klenerman P. Antibody opsonization enhances MAIT cell responsiveness to bacteria via a TNF-dependent mechanism. Immunol Cell Biol 2019; 97:538-551. [PMID: 30695101 PMCID: PMC6767153 DOI: 10.1111/imcb.12239] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Revised: 12/14/2018] [Accepted: 01/25/2019] [Indexed: 12/11/2022]
Abstract
Mucosal-associated invariant T (MAIT) cells are an abundant human T-cell subset with antimicrobial properties. They can respond to bacteria presented via antigen-presenting cells (APCs) such as macrophages, which present bacterially derived ligands from the riboflavin synthesis pathway on MR1. Moreover, MAIT cells are also highly responsive to cytokines which enhance and even substitute for T-cell receptor-mediated signaling. The mechanisms leading to an efficient presentation of bacteria to MAIT cells by APCs have not been fully elucidated. Here, we showed that the monocytic cell line THP-1 and B cells activated MAIT cells differentially in response to Escherichia coli. THP-1 cells were generally more potent in inducing IFNγ and IFNγ/TNF production by MAIT cells. Furthermore, THP-1, but not B, cells produced TNF upon bacterial stimulation, which in turn supported IFNγ production by MAIT cells. Finally, we addressed the role of antibody-dependent opsonization of bacteria in the activation of MAIT cells using in vitro models. We found that opsonization had a substantial impact on downstream MAIT cell activation by monocytes. This was associated with enhanced activation of monocytes and increased TNF release. Importantly, this TNF acted in concert with other cytokines to drive MAIT cell activation. These data indicate both a significant interaction between adaptive and innate immunity in the response to bacteria, and an important role for TNF in MAIT cell triggering.
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Affiliation(s)
- Zoltán Bánki
- Division of Virology, Medical University of Innsbruck, Innsbruck, Austria
| | - Lisette Krabbendam
- Peter Medawar Building for Pathogen Research, University of Oxford, Oxford, UK
| | - Dominik Klaver
- Division of Virology, Medical University of Innsbruck, Innsbruck, Austria
| | - Tianqi Leng
- Peter Medawar Building for Pathogen Research, University of Oxford, Oxford, UK
| | - Simon Kruis
- Division of Virology, Medical University of Innsbruck, Innsbruck, Austria
| | - Hema Mehta
- Peter Medawar Building for Pathogen Research, University of Oxford, Oxford, UK
| | - Brigitte Müllauer
- Division of Virology, Medical University of Innsbruck, Innsbruck, Austria
| | - Dorothea Orth-Höller
- Division of Hygiene and Medical Microbiology, Medical University of Innsbruck, Innsbruck, Austria
| | - Heribert Stoiber
- Division of Virology, Medical University of Innsbruck, Innsbruck, Austria
| | | | - Paul Klenerman
- Peter Medawar Building for Pathogen Research, University of Oxford, Oxford, UK
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47
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Lindholm M, Min Aung K, Nyunt Wai S, Oscarsson J. Role of OmpA1 and OmpA2 in Aggregatibacter actinomycetemcomitans and Aggregatibacter aphrophilus serum resistance. J Oral Microbiol 2018; 11:1536192. [PMID: 30598730 PMCID: PMC6225413 DOI: 10.1080/20002297.2018.1536192] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Revised: 10/03/2018] [Accepted: 10/10/2018] [Indexed: 12/27/2022] Open
Abstract
Aggregatibacter actinomycetemcomitans and Aggregatibacter aphrophilus belong to the HACEK group of fastidious Gram-negative organisms, a recognized cause of infective endocarditis. A. actinomycetemcomitans is also implicated in aggressive forms of periodontitis. We demonstrated that A. aphrophilus strains, as A. actinomycetemcomitans are ubiquitously serum resistant. Both species encode two Outer membrane protein A paralogues, here denoted OmpA1 and OmpA2. As their respective pangenomes contain several OmpA1 and OmpA2 alleles, they represent potential genotypic markers. A naturally competent strain of A. actinomycetemcomitans and A. aphrophilus, respectively were used to elucidate if OmpA1 and OmpA2 contribute to serum resistance. Whereas OmpA1 was critical for survival of A. actinomycetemcomitans D7SS in 50% normal human serum (NHS), serum resistant ompA1 mutants were fortuitously obtained, expressing enhanced levels of OmpA2. Similarly, OmpA1 rather than OmpA2 was a major contributor to serum resistance of A. aphrophilus HK83. Far-Western blot revealed that OmpA1AA, OmpA2AA, and OmpA1AP can bind to C4-binding protein, an inhibitor of classical and mannose-binding lectin (MBL) complement activation. Indeed, ompA1 mutants were susceptible to these pathways, but also to alternative complement activation. This may at least partly reflect a compromised outer membrane integrity but is also consistent with alternative mechanisms involved in OmpA-mediated serum resistance.
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Affiliation(s)
- Mark Lindholm
- Oral Microbiology, Department of Odontology, Umeå University, Umeå, Sweden
| | - Kyaw Min Aung
- Department of Molecular Biology and the Umeå Centre for Microbial Research (UCMR), Umeå University, Umeå, Sweden
| | - Sun Nyunt Wai
- Department of Molecular Biology and the Umeå Centre for Microbial Research (UCMR), Umeå University, Umeå, Sweden
| | - Jan Oscarsson
- Oral Microbiology, Department of Odontology, Umeå University, Umeå, Sweden
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48
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Harris S, Piotrowska MJ, Goldstone RJ, Qi R, Foster G, Dobrindt U, Madec JY, Valat C, Rao FV, Smith DGE. Variant O89 O-Antigen of E. coli Is Associated With Group 1 Capsule Loci and Multidrug Resistance. Front Microbiol 2018; 9:2026. [PMID: 30233517 PMCID: PMC6128206 DOI: 10.3389/fmicb.2018.02026] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Accepted: 08/09/2018] [Indexed: 11/13/2022] Open
Abstract
Bacterial surface polysaccharides play significant roles in fitness and virulence. In Gram-negative bacteria such as Escherichia coli, major surface polysaccharides are lipopolysaccharide (LPS) and capsule, representing O- and K-antigens, respectively. There are multiple combinations of O:K types, many of which are well-characterized and can be related to ecotype or pathotype. In this investigation, we have identified a novel O:K permutation resulting through a process of major genome reorganization in a clade of E. coli. A multidrug-resistant, extended-spectrum β-lactamase (ESBL)-producing strain - E. coli 26561 - represented a prototype of strains combining a locus variant of O89 and group 1 capsular polysaccharide. Specifically, the variant O89 locus in this strain was truncated at gnd, flanked by insertion sequences and located between nfsB and ybdK and we apply the term O89m for this variant. The prototype lacked colanic acid and O-antigen loci between yegH and hisI with this tandem polysaccharide locus being replaced with a group 1 capsule (G1C) which, rather than being a recognized E. coli capsule type, this locus matched to Klebsiella K10 capsule type. A genomic survey identified more than 200 E. coli strains which possessed the O89m locus variant with one of a variety of G1C types. Isolates from our collection with the combination of O89m and G1C all displayed a mucoid phenotype and E. coli 26561 was unusual in exhibiting a mucoviscous phenotype more recognized as a characteristic among Klebsiella strains. Despite the locus truncation and novel location, all O89m:G1C strains examined showed a ladder pattern typifying smooth LPS and also showed high molecular weight, alcian blue-staining polysaccharide in cellular and/or extra-cellular fractions. Expression of both O-antigen and capsule biosynthesis loci were confirmed in prototype strain 26561 through quantitative proteome analysis. Further in silico exploration of more than 200 E. coli strains possessing the O89m:G1C combination identified a very high prevalence of multidrug resistance (MDR) - 85% possessed resistance to three or more antibiotic classes and a high proportion (58%) of these carried ESBL and/or carbapenemase. The increasing isolation of O89m:G1C isolates from extra-intestinal infection sites suggests that these represents an emergent clade of invasive, MDR E. coli.
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Affiliation(s)
- Susan Harris
- Institute of Biological Chemistry, Biophysics and Bioengineering, Heriot-Watt University, Edinburgh, United Kingdom
| | - Marta J Piotrowska
- Institute of Biological Chemistry, Biophysics and Bioengineering, Heriot-Watt University, Edinburgh, United Kingdom
| | | | - Ruby Qi
- Institute of Biological Chemistry, Biophysics and Bioengineering, Heriot-Watt University, Edinburgh, United Kingdom
| | - Geoffrey Foster
- Veterinary Services, SAC Consulting, Scotland's Rural College, Inverness, United Kingdom
| | - Ulrich Dobrindt
- Institute of Hygiene, University of Münster, Münster, Germany
| | - Jean-Yves Madec
- Unité Antibiorésistances et Virulences Bactériennes, Anses Laboratoire de Lyon, Université Lyon-1, Lyon, France
| | - Charlotte Valat
- Unité Antibiorésistances et Virulences Bactériennes, Anses Laboratoire de Lyon, Université Lyon-1, Lyon, France
| | | | - David G E Smith
- Institute of Biological Chemistry, Biophysics and Bioengineering, Heriot-Watt University, Edinburgh, United Kingdom
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49
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Nauser CL, Howard MC, Fanelli G, Farrar CA, Sacks S. Collectin-11 (CL-11) Is a Major Sentinel at Epithelial Surfaces and Key Pattern Recognition Molecule in Complement-Mediated Ischaemic Injury. Front Immunol 2018; 9:2023. [PMID: 30237800 PMCID: PMC6136055 DOI: 10.3389/fimmu.2018.02023] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Accepted: 08/16/2018] [Indexed: 12/31/2022] Open
Abstract
The complement system is a dynamic subset of the innate immune system, playing roles in host defense, clearance of immune complexes and cell debris, and priming the adaptive immune response. Over the last 40 years our understanding of the complement system has evolved from identifying its presence and recognizing its role in the blood to now focusing on understanding the role of local complement synthesis in health and disease. In particular, the local synthesis of complement was found to have an involvement in mediating ischaemic injury, including following transplantation. Recent work on elucidating the triggers of local complement synthesis and activation in renal tissue have led to the finding that Collectin-11 (CL-11) engages with L-fucose at the site of ischaemic stress, namely at the surface of the proximal tubular epithelial cells. What remains unknown is the precise structure of the damage-associated ligand that participates in CL-11 binding and subsequent complement activation. In this article, we will discuss our hypothesis regarding the role of CL-11 as an integral tissue-based pattern recognition molecule which we postulate has a significant contributory role in complement-mediated ischaemic injury.
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Affiliation(s)
- Christopher L Nauser
- MRC Centre for Transplantation, School of Immunology and Microbial Sciences, King's College London, Guy's and St. Thomas' NHS Foundation Trust, London, United Kingdom
| | - Mark C Howard
- MRC Centre for Transplantation, School of Immunology and Microbial Sciences, King's College London, Guy's and St. Thomas' NHS Foundation Trust, London, United Kingdom
| | - Giorgia Fanelli
- MRC Centre for Transplantation, School of Immunology and Microbial Sciences, King's College London, Guy's and St. Thomas' NHS Foundation Trust, London, United Kingdom
| | - Conrad A Farrar
- MRC Centre for Transplantation, School of Immunology and Microbial Sciences, King's College London, Guy's and St. Thomas' NHS Foundation Trust, London, United Kingdom
| | - Steven Sacks
- MRC Centre for Transplantation, School of Immunology and Microbial Sciences, King's College London, Guy's and St. Thomas' NHS Foundation Trust, London, United Kingdom
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50
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Li MF, Sun L. Edwardsiella tarda Sip2: A Serum-Induced Protein That Is Essential to Serum Survival, Acid Resistance, Intracellular Replication, and Host Infection. Front Microbiol 2018; 9:1084. [PMID: 29887847 PMCID: PMC5980991 DOI: 10.3389/fmicb.2018.01084] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2018] [Accepted: 05/07/2018] [Indexed: 12/12/2022] Open
Abstract
Edwardsiella tarda is a broad-host pathogen that can infect mammals, reptiles, and fish. E. tarda exhibits a remarkable ability to survive in host serum and replicate in host phagocytes, but the underlining mechanism is unclear. In this study, in order to identify E. tarda proteins involved in serum resistance, iTRAQ proteomic analysis was performed to examine the whole-cell protein profiles of TX01, a pathogenic E. tarda isolate, in response to serum treatment. Of the differentially expressed proteins identified, one (named Sip2) possesses a conserved hydrogenase domain and is homologous to the putative hydrogenase accessory protein HypB. When Sip2 was expressed in Escherichia coli, it significantly enhanced the survival of the host cells in serum. Compared to TX01, the sip2 knockout, TX01Δsip2, was dramatically reduced in the ability of hydrogenase activity, serum resistance, intracellular replication, dissemination in fish tissues, and causing mortality in infected fish. The lost virulence capacities of TX01Δsip2 were restored by complementation with the sip2 gene. Furthermore, TX01Δsip2 was significantly reduced in the capacity to grow under low pHs and iron-depleted conditions, and was unable to maintain its internal pH in acidic environment. Taken together, these results indicate that Sip2 is a novel serum-induced protein that is essential to serum resistance, cellular and tissue infection, and coping with acidic stress via its ability to modulate intracellular pH.
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Affiliation(s)
- Mo-fei Li
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
| | - Li Sun
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
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