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Evolution of tetraspanin antigens in the zoonotic Asian blood fluke Schistosoma japonicum. Parasit Vectors 2023; 16:97. [PMID: 36918965 PMCID: PMC10012309 DOI: 10.1186/s13071-023-05706-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2022] [Accepted: 02/17/2023] [Indexed: 03/16/2023] Open
Abstract
BACKGROUND Despite successful control efforts in China over the past 60 years, zoonotic schistosomiasis caused by Schistosoma japonicum remains a threat with transmission ongoing and the risk of localised resurgences prompting calls for a novel integrated control strategy, with an anti-schistosome vaccine as a core element. Anti-schistosome vaccine development and immunisation attempts in non-human mammalian host species, intended to interrupt transmission, and utilising various antigen targets, have yielded mixed success, with some studies highlighting variation in schistosome antigen coding genes (ACGs) as possible confounders of vaccine efficacy. Thus, robust selection of target ACGs, including assessment of their genetic diversity and antigenic variability, is paramount. Tetraspanins (TSPs), a family of tegument-surface antigens in schistosomes, interact directly with the host's immune system and are promising vaccine candidates. Here, for the first time to our knowledge, diversity in S. japonicum TSPs (SjTSPs) and the impact of diversifying selection and sequence variation on immunogenicity in these protiens were evaluated. METHODS SjTSP sequences, representing parasite populations from seven provinces across China, were gathered by baiting published short-read NGS data and were analysed using in silico methods to measure sequence variation and selection pressures and predict the impact of selection on variation in antigen protein structure, function and antigenic propensity. RESULTS Here, 27 SjTSPs were identified across three subfamilies, highlighting the diversity of TSPs in S. japonicum. Considerable variation was demonstrated for several SjTSPs between geographical regions/provinces, revealing that episodic, diversifying positive selection pressures promote amino acid variation/variability in the large extracellular loop (LEL) domain of certain SjTSPs. Accumulating polymorphisms in the LEL domain of SjTSP-2, -8 and -23 led to altered structural, functional and antibody binding characteristics, which are predicted to impact antibody recognition and possibly blunt the host's ability to respond to infection. Such changes, therefore, appear to represent a mechanism utilised by S. japonicum to evade the host's immune system. CONCLUSION Whilst the genetic and antigenic geographic variability observed amongst certain SjTSPs could present challenges to vaccine development, here we demonstrate conservation amongst SjTSP-1, -13 and -14, revealing their likely improved utility as efficacious vaccine candidates. Importantly, our data highlight that robust evaluation of vaccine target variability in natural parasite populations should be a prerequisite for anti-schistosome vaccine development.
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Characterization of Bordetella pertussis Strains Isolated from India. Pathogens 2022; 11:pathogens11070794. [PMID: 35890038 PMCID: PMC9322502 DOI: 10.3390/pathogens11070794] [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: 05/16/2022] [Revised: 06/11/2022] [Accepted: 06/16/2022] [Indexed: 11/25/2022] Open
Abstract
Despite high level vaccination and the availability of two different types of vaccines, whole cell (wP) and acellular vaccines (aP), the resurgence of pertussis has been reported in many countries. Antigenic variation within circulating and vaccine strains is the most documented reason reported for the resurgence of pertussis. Research on genetic divergence among circulating and vaccine strains has largely been reported in countries using aP vaccines. There are inadequate data available for antigenic variation in B. pertussis from wP-using countries. India has used wP for more than 40 years in their primary immunization program. The present study reports five clinical isolates of B. pertussis from samples of pediatric patients with pertussis symptoms observed in India. Genotypic and phenotypic characterization of clinical isolates were performed by serotyping, genotyping, whole genome analyses and comparative genomics. All clinical isolates showed serotype 1, 2 and 3 based on the presence of fimbriae 2 and 3. Genotyping showed genetic similarities in allele types for five aP genes within vaccine strains and clinical isolates reported from India. The presence of the ptxP3 genotype was observed in two out of five clinical isolates. Whole-genome sequencing was performed for clinical isolates using the hybrid strategy of combining Illumina (short reads) and oxford nanopore (long reads) sequencing strategies. Clinical isolates (n = 5) and vaccine strains (n = 7) genomes of B. pertussis from India were compared with 744 B. pertussis closed genomes available in the public databases. The phylogenomic comparison of B. pertussis genomes reported from India will be advantageous in better understanding pertussis resurgence reported globally with respect to pathogen adaptation.
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Saedi S, Safarchi A, Moghadam FT, Heidarzadeh S, Nikbin VS, Shahcheraghi F. Fha Deficient Bordetella pertussis Isolates in Iran with 50 Years Whole Cell Pertussis Vaccination. IRANIAN JOURNAL OF PUBLIC HEALTH 2021; 50:1454-1462. [PMID: 34568185 PMCID: PMC8426785 DOI: 10.18502/ijph.v50i7.6636] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/16/2020] [Accepted: 05/19/2020] [Indexed: 11/24/2022]
Abstract
Background: Bordetella pertussis, a highly contagious respiratory. Notably, the resurgence of pertussis has recently been associated with the lacking production of vaccine virulence factors. This study aimed to screen pertactin (Prn) and filamentous hemagglutinin (Fha) production in Iran with 50 years’ whole cell vaccine (WCV) immunization program. Methods: Overall, 130 B. pertussis isolates collected from Pertussis Reference Laboratory of Iran during 2005–2018. Real-time PCR was performed by targeting IS481, ptxP, IS1001 and IS1002 for species confirmation of B. pertussis. Western-blot was used to evaluate the expression of virulence factors (pertactin and filamentous hemagglutinin). Results: All tested B. pertussis isolates expressed Prn and all except two isolates expressed Fha. We have sequenced genomes of these strains and identified differences compared with genome reference B. pertussis Tohama I. Conclusion: Many countries reporting Prn and Fha-deficiency due to acellular vaccine (ACV) pressure. Our results demonstrate in a country with WCV history, Fha-deficient isolates may rise independently. However, Prn-deficient isolates are more under the ACV pressure in B. pertussis isolates. Continues surveillance will provide a better understanding of the effect of WCV on the evolution of the pathogen deficiency.
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Affiliation(s)
- Samaneh Saedi
- Department of Bacteriology, Pasteur Institute of Iran, Tehran, Iran
| | - Azadeh Safarchi
- Department of Bacteriology, Pasteur Institute of Iran, Tehran, Iran
| | | | - Siamak Heidarzadeh
- Department of Microbiology and Virology, School of Medicine, Zanjan University of Medical Sciences, Zanjan, Iran
| | | | - Fereshteh Shahcheraghi
- Pertussis Reference Laboratory, Department of Bacteriology, Pasteur Institute of Iran, Tehran, Iran
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Di Camillo C, Vittucci AC, Antilici L, Ciarlitto C, Linardos G, Concato C, Lancella L, Villani A. Pertussis in early life: underdiagnosed, severe, and risky disease. A seven-year experience in a pediatric tertiary-care hospital. Hum Vaccin Immunother 2021; 17:705-713. [PMID: 32755440 PMCID: PMC7993225 DOI: 10.1080/21645515.2020.1791617] [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: 03/23/2020] [Revised: 06/10/2020] [Accepted: 06/28/2020] [Indexed: 10/23/2022] Open
Abstract
AIM Pertussis continues to be a common worldwide infection in pediatric and adult populations.We aimed to study epidemiological and clinical characteristics of infants and children admitted for pertussis to a tertiary-care hospital and to investigate the risk factors for pediatric intensive care unit (PICU) admission. MATERIALS AND METHODS With a retrospective study, we analyzed all medical reports of patients admitted to Bambino Gesù Children's Hospital in Rome from January 2011 to December 2018 with a diagnosis of pertussis. RESULTS We examined 195 patients. The majority of hospitalized children (66.15%) were <3 months of age. No mother had received pertussis containing vaccine during pregnancy. Ten cases required admission in PICU. The age at admission was lower in PICU patients with respect to ward patients (42.8 vs 240 days; p < .0007), length of hospital stay was longer in PICU group (24.7 vs 7.52 days; p < .003). Patients who needed PICU admission had greater white blood cell count at hospital admission compared with those hospitalized in the pediatric ward. One infant died and one had encephalitis. CONCLUSIONS Pertussis is a remerging disease. In infants, it is associated with significant morbidity and mortality. In recent years, many countries have implemented different vaccination strategies and public health measures to prevent the increase in pertussis cases. Maternal vaccination has been shown to be highly protective for infants <3 months of age before they can develop their own immunity via vaccination.
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Affiliation(s)
- Chiara Di Camillo
- Academic Department of Pediatrics, Pediatric and Infectious Disease Unit, Children’s Hospital Bambino Gesù (IRCCS), Rome, Italy
| | - Anna Chiara Vittucci
- Academic Department of Pediatrics, Pediatric and Infectious Disease Unit, Children’s Hospital Bambino Gesù (IRCCS), Rome, Italy
| | - Livia Antilici
- Academic Department of Pediatrics, Tor Vergata University of Rome, Rome, Italy
| | - Claudia Ciarlitto
- Academic Department of Pediatrics, Tor Vergata University of Rome, Rome, Italy
| | - Giulia Linardos
- Virology Unit, Bambino Gesù Children’s Hospital (IRCCS), Rome, Italy
| | - Carlo Concato
- Virology Unit, Bambino Gesù Children’s Hospital (IRCCS), Rome, Italy
| | - Laura Lancella
- Academic Department of Pediatrics, Pediatric and Infectious Disease Unit, Children’s Hospital Bambino Gesù (IRCCS), Rome, Italy
| | - Alberto Villani
- Academic Department of Pediatrics, Pediatric and Infectious Disease Unit, Children’s Hospital Bambino Gesù (IRCCS), Rome, Italy
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Alai S, Ghattargi VC, Gautam M, Patel K, Pawar SP, Dhotre DP, Shaligram U, Gairola S. Comparative genomics of whole-cell pertussis vaccine strains from India. BMC Genomics 2020; 21:345. [PMID: 32381023 PMCID: PMC7204287 DOI: 10.1186/s12864-020-6724-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2020] [Accepted: 04/06/2020] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND Despite high vaccination coverage using acellular (ACV) and whole-cell pertussis (WCV) vaccines, the resurgence of pertussis is observed globally. Genetic divergence in circulating strains of Bordetella pertussis has been reported as one of the contributing factors for the resurgence of the disease. Our current knowledge of B. pertussis genetic evolution in circulating strains is mostly based on studies conducted in countries using ACVs targeting only a few antigens used in the production of ACVs. To better understand the adaptation to vaccine-induced selection pressure, it will be essential to study B. pertussis populations in developing countries which are using WCVs. India is a significant user and global supplier of WCVs. We report here comparative genome analyses of vaccine and clinical isolates reported from India. Whole-genome sequences obtained from vaccine strains: WCV (J445, J446, J447 and J448), ACV (BP165) were compared with Tohama-I reference strain and recently reported clinical isolates from India (BPD1, BPD2). Core genome-based phylogenetic analysis was also performed using 166 isolates reported from countries using ACV. RESULTS Whole-genome analysis of vaccine and clinical isolates reported from India revealed high genetic similarity and conserved genome among strains. Phylogenetic analysis showed that clinical and vaccine strains share genetic closeness with reference strain Tohama-I. The allelic profile of vaccine strains (J445:ptxP1/ptxA2/prn1/fim2-1/fim3-1; J446: ptxP2/ptxA4/prn7/fim2-2/fim3-1; J447 and J448: ptxP1/ptxA1/ prn1/fim2-1/fim3-1), which matched entirely with clinical isolates (BPD1:ptxP1/ptxA1/prn1/fim2-1 and BPD2: ptxP1/ptxA1/prn1/fim2-1) reported from India. Multi-locus sequence typing (MLST) demonstrated the presence of dominant sequence types ST2 and primitive ST1 in vaccine strains which will allow better coverage against circulating strains of B. pertussis. CONCLUSIONS The study provides a detailed characterization of vaccine and clinical strains reported from India, which will further facilitate epidemiological studies on genetic shifts in countries which are using WCVs in their immunization programs.
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Affiliation(s)
- Shweta Alai
- Department of Health and Biological Sciences, Symbiosis International University, Pune, Maharashtra, 412115, India
| | - Vikas C Ghattargi
- National Centre for Microbial Resource, National Centre for Cell Science, Pune, Maharashtra, 411021, India
| | - Manish Gautam
- Serum Institute of India Pvt. Ltd, Pune, Maharashtra, 411028, India
| | - Krunal Patel
- Serum Institute of India Pvt. Ltd, Pune, Maharashtra, 411028, India
| | - Shrikant P Pawar
- National Centre for Microbial Resource, National Centre for Cell Science, Pune, Maharashtra, 411021, India
| | - Dhiraj P Dhotre
- National Centre for Microbial Resource, National Centre for Cell Science, Pune, Maharashtra, 411021, India
| | - Umesh Shaligram
- Serum Institute of India Pvt. Ltd, Pune, Maharashtra, 411028, India
| | - Sunil Gairola
- Serum Institute of India Pvt. Ltd, Pune, Maharashtra, 411028, India.
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Wong A, Opinel A, Combes SJB, Toubiana J, Brisse S. Determining Factors for Pertussis Vaccination Policy: A Study in Five EU Countries. Vaccines (Basel) 2020; 8:vaccines8010046. [PMID: 31991855 PMCID: PMC7158661 DOI: 10.3390/vaccines8010046] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2019] [Revised: 01/20/2020] [Accepted: 01/21/2020] [Indexed: 01/26/2023] Open
Abstract
Pertussis vaccination policy varies across Europe, not only in the type of vaccine-whole cell (wP) vs. acellular (aP1/2/3/5)-but also in the schedule and recommendation for parents. This study aims to investigate the determining factors for the type of vaccine, immunization schedule and maternal immunization recommendation. From March to May 2019, experts in national health agencies and major academic or research institutions from Denmark, France, Poland, Sweden and the UK were invited to a semi-structured interview. Thematic analysis was performed on the transcripts using a codebook formulated by three coders. Inter-coder agreement was assessed. Fifteen expert interviews were conducted. The identified driving factors for pertussis vaccine policy were classified into three domains: scientific factors, sociological factors, and pragmatic factors. The determining factors for the type of vaccine were prescriber's preference, concern of adverse events following immunization (AEFI), effectiveness, and consideration of other vaccine components in combined vaccines. The determining factors for infant schedule were immunity response and the potential to improve coverage and timeliness. The determining factors for maternal immunization were infant mortality and public acceptability. To conclude, socio-political and pragmatic factors were, besides scientific factors, important in determining the pertussis vaccine type, schedule of childhood immunization and recommendations for parents.
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Affiliation(s)
- Anabelle Wong
- Institut Pasteur/INSERM/University of Versailles Saint Quentin, UMR 1181 Biostatistics, Biomathematics, Pharmacoepidemiology and Infectious Diseases, 25 rue du Dr Roux, CEDEX 15, F-75724 Paris, France;
- EHESP French School of Public Health, F-35000 Rennes, France
- ScHARR, The University of Sheffield, 30 Regent Street, Sheffield S1 4DA, UK
- Correspondence:
| | - Annick Opinel
- Institut Pasteur/INSERM/University of Versailles Saint Quentin, UMR 1181 Biostatistics, Biomathematics, Pharmacoepidemiology and Infectious Diseases, 25 rue du Dr Roux, CEDEX 15, F-75724 Paris, France;
| | - Simon Jean-Baptiste Combes
- Univ Rennes, EHESP, CNRS, ARENES—UMR 6051, F-35000 Rennes, France;
- French Collaborative Institute on Migration, 93322 Aubervilliers, France
| | - Julie Toubiana
- Institut Pasteur, Unit Biodiversity and Epidemiology of Bacterial Pathogens, 25 rue du Dr Roux, CEDEX 15, F-75724 Paris, France; (J.T.); (S.B.)
- National Reference Center for Whooping Cough and OtherBordetella Infections, Institut Pasteur, 25 rue du Dr Roux, CEDEX 15, F-75724 Paris, France
- Department of General Paediatrics and Infectious Diseases, Necker-Enfants malades University Hospital, Université de Paris, AP-HP, 135 rue de Sevres, 75015 Paris, France
| | - Sylvain Brisse
- Institut Pasteur, Unit Biodiversity and Epidemiology of Bacterial Pathogens, 25 rue du Dr Roux, CEDEX 15, F-75724 Paris, France; (J.T.); (S.B.)
- National Reference Center for Whooping Cough and OtherBordetella Infections, Institut Pasteur, 25 rue du Dr Roux, CEDEX 15, F-75724 Paris, France
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MacArthur I, Belcher T, King JD, Ramasamy V, Alhammadi M, Preston A. The evolution of Bordetella pertussis has selected for mutations of acr that lead to sensitivity to hydrophobic molecules and fatty acids. Emerg Microbes Infect 2019; 8:603-612. [PMID: 30966996 PMCID: PMC6461096 DOI: 10.1080/22221751.2019.1601502] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Whooping cough, or pertussis, is resurgent in numerous countries worldwide. This has renewed interest in Bordetella pertussis biology and vaccinology. The in vitro growth of B. pertussis has been a source of difficulty, both for the study of the organism and the production of pertussis vaccines. It is inhibited by fatty acids and other hydrophobic molecules. The AcrAB efflux system is present in many different bacteria and in combination with an outer membrane factor exports acriflavine and other small hydrophobic molecules from the cell. Here, we identify that the speciation of B. pertussis has selected for an Acr system that is naturally mutated and displays reduced activity compared to B. bronchiseptica, in which the system appears intact. Replacement of the B. pertussis locus with that of B. bronchiseptica conferred higher levels of resistance to growth inhibition by acriflavine and fatty acids. In addition, we identified that the transcription of the locus is repressed by a LysR-type transcriptional regulator. Palmitate de-represses the expression of the acr locus, dependent on the LysR regulator, strongly suggesting that it is a transcriptional repressor that is regulated by palmitate. It is intriguing that the speciation of B. pertussis has selected for a reduction in activity of the Acr efflux system that typically is regarded as protective to bacteria.
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Affiliation(s)
- Iain MacArthur
- a The Milner Centre for Evolution, University of Bath , Bath , UK.,b Department of Biology and Biochemistry , University of Bath , Bath , UK
| | - Thomas Belcher
- b Department of Biology and Biochemistry , University of Bath , Bath , UK
| | - Jerry D King
- b Department of Biology and Biochemistry , University of Bath , Bath , UK
| | - Vasantha Ramasamy
- b Department of Biology and Biochemistry , University of Bath , Bath , UK
| | - Munirah Alhammadi
- b Department of Biology and Biochemistry , University of Bath , Bath , UK
| | - Andrew Preston
- a The Milner Centre for Evolution, University of Bath , Bath , UK.,b Department of Biology and Biochemistry , University of Bath , Bath , UK
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Di Mattia G, Nicolai A, Frassanito A, Petrarca L, Nenna R, Midulla F. Pertussis: New preventive strategies for an old disease. Paediatr Respir Rev 2019; 29:68-73. [PMID: 29914744 DOI: 10.1016/j.prrv.2018.03.011] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Revised: 03/13/2018] [Accepted: 03/16/2018] [Indexed: 12/14/2022]
Abstract
In the last twenty years, despite high vaccination coverage, epidemics of pertussis are occurring in both developing and developed countries. Many reasons could explain the pertussis resurgence: the increasing awareness of the disease, the availability of new diagnostic tests with higher sensitivity, the emergence of new Bordetella pertussis (B. pertussis) strains different from those contained in the current vaccines, the asymptomatic transmission of B. pertussis in adolescents and adults and the shorter duration of protection given by the acellular pertussis (aP) vaccine. New preventive strategies have already been implemented, such as booster doses of aP vaccine in adolescents and adults, maternal immunisation during pregnancy and the "cocooning" strategy, but more are still needed. Knowing what is new about this old disease is necessary to reduce its incidence and to protect infants too young to be vaccinated, which have the highest risk of complications and death.
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Affiliation(s)
- Greta Di Mattia
- Department of Paediatrics, "Sapienza" University of Rome, V.le Regina Elena 324, 00161 Rome, Italy
| | - Ambra Nicolai
- Department of Paediatrics, "Sapienza" University of Rome, V.le Regina Elena 324, 00161 Rome, Italy
| | - Antonella Frassanito
- Department of Paediatrics, "Sapienza" University of Rome, V.le Regina Elena 324, 00161 Rome, Italy
| | - Laura Petrarca
- Department of Paediatrics, "Sapienza" University of Rome, V.le Regina Elena 324, 00161 Rome, Italy
| | - Raffaella Nenna
- Department of Paediatrics, "Sapienza" University of Rome, V.le Regina Elena 324, 00161 Rome, Italy
| | - Fabio Midulla
- Department of Paediatrics, "Sapienza" University of Rome, V.le Regina Elena 324, 00161 Rome, Italy.
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Abstract
Safe and efficacious vaccines are arguably the most successful medical interventions of all time. Yet the ongoing discovery of new pathogens, along with emergence of antibiotic-resistant pathogens and a burgeoning population at risk of such infections, imposes unprecedented public health challenges. To meet these challenges, innovative strategies to discover and develop new or improved anti-infective vaccines are necessary. These approaches must intersect the most meaningful insights into protective immunity and advanced technologies with capabilities to deliver immunogens for optimal immune protection. This goal is considered through several recent advances in host-pathogen relationships, conceptual strides in vaccinology, and emerging technologies. Given a clear and growing risk of pandemic disease should the threat of infection go unmet, developing vaccines that optimize protective immunity against high-priority and antibiotic-resistant pathogens represents an urgent and unifying imperative.
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Affiliation(s)
- Michael R Yeaman
- Department of Medicine, David Geffen School of Medicine at UCLA, Los Angeles, California 90024.,Division of Molecular Medicine, Department of Medicine, Harbor-UCLA Medical Center, Torrance, California 90509; .,Division of Infectious Diseases, Department of Medicine, Harbor-UCLA Medical Center, Torrance, California 90509.,Los Angeles Biomedical Research Institute, Torrance, California 90502
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10
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Fyson N, King J, Belcher T, Preston A, Colijn C. A curated genome-scale metabolic model of Bordetella pertussis metabolism. PLoS Comput Biol 2017; 13:e1005639. [PMID: 28715411 PMCID: PMC5553986 DOI: 10.1371/journal.pcbi.1005639] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Revised: 08/11/2017] [Accepted: 06/15/2017] [Indexed: 11/30/2022] Open
Abstract
The Gram-negative bacterium Bordetella pertussis is the causative agent of whooping cough, a serious respiratory infection causing hundreds of thousands of deaths annually worldwide. There are effective vaccines, but their production requires growing large quantities of B. pertussis. Unfortunately, B. pertussis has relatively slow growth in culture, with low biomass yields and variable growth characteristics. B. pertussis also requires a relatively expensive growth medium. We present a new, curated flux balance analysis-based model of B. pertussis metabolism. We enhance the model with an experimentally-determined biomass objective function, and we perform extensive manual curation. We test the model’s predictions with a genome-wide screen for essential genes using a transposon-directed insertional sequencing (TraDIS) approach. We test its predictions of growth for different carbon sources in the medium. The model predicts essentiality with an accuracy of 83% and correctly predicts improvements in growth under increased glutamate:fumarate ratios. We provide the model in SBML format, along with gene essentiality predictions. Metabolic flux models have been used to understand how organisms adapt their metabolism under different growth conditions, and are finding increasing application in synthetic biology and biotechnology. One barrier to progress in this field is the construction and curation of metabolic flux models for new organisms. Here we present a curated genome-scale metabolic flux model for Bordetella pertussis, the causative agent of whooping cough. Producing vaccines against whooping cough requires growing B. pertussis in large volumes. However, its growth is relatively slow, final yields of biomass are relatively low and growth characteristics can be variable. Understanding B. pertussis metabolism has applications to improving vaccine production, as well as in understanding the basic biology of this organism.
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Affiliation(s)
- Nick Fyson
- Department of Mathematics, Imperial College, London, UK
| | - Jerry King
- The Milner Centre for Evolution and Department of Biology and Biochemistry, University of Bath, Bath, UK
| | - Thomas Belcher
- The Milner Centre for Evolution and Department of Biology and Biochemistry, University of Bath, Bath, UK
| | - Andrew Preston
- The Milner Centre for Evolution and Department of Biology and Biochemistry, University of Bath, Bath, UK
| | - Caroline Colijn
- Department of Mathematics, Imperial College, London, UK
- * E-mail:
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