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Jenkins CH, Scott AE, O’Neill PA, Norville IH, Prior JL, Ireland PM. The Arabinose 5-Phosphate Isomerase KdsD Is Required for Virulence in Burkholderia pseudomallei. J Bacteriol 2023; 205:e0003423. [PMID: 37458584 PMCID: PMC10448790 DOI: 10.1128/jb.00034-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Accepted: 06/06/2023] [Indexed: 08/25/2023] Open
Abstract
Burkholderia pseudomallei is the causative agent of melioidosis, which is endemic primarily in Southeast Asia and northern Australia but is increasingly being seen in other tropical and subtropical regions of the world. Melioidosis is associated with high morbidity and mortality rates, which is mediated by the wide range of virulence factors encoded by B. pseudomallei. These virulence determinants include surface polysaccharides such as lipopolysaccharide (LPS) and capsular polysaccharides (CPS). Here, we investigated a predicted arabinose-5-phosphate isomerase (API) similar to KdsD in B. pseudomallei strain K96243. KdsD is required for the production of the highly conserved 3-deoxy-d-manno-octulosonic acid (Kdo), a key sugar in the core region of LPS. Recombinant KdsD was expressed and purified, and API activity was determined. Although a putative API paralogue (KpsF) is also predicted to be encoded, the deletion of kdsD resulted in growth defects, loss of motility, reduced survival in RAW 264.7 murine macrophages, and attenuation in a BALB/c mouse model of melioidosis. Suppressor mutations were observed during a phenotypic screen for motility, revealing single nucleotide polymorphisms or indels located in the poorly understood CPS type IV cluster. Crucially, suppressor mutations did not result in reversion of attenuation in vivo. This study demonstrates the importance of KdsD for B. pseudomallei virulence and highlights further the complex nature of the polysaccharides it produces. IMPORTANCE The intrinsic resistance of B. pseudomallei to many antibiotics complicates treatment. This opportunistic pathogen possesses a wide range of virulence factors, resulting in severe and potentially fatal disease. Virulence factors as targets for drug development offer an alternative approach to combat pathogenic bacteria. Prior to initiating early drug discovery approaches, it is important to demonstrate that disruption of the target gene will prevent the development of disease. This study highlights the fact that KdsD is crucial for virulence of B. pseudomallei in an animal model of infection and provides supportive phenotypic characterization that builds a foundation for future therapeutic development.
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Affiliation(s)
- Christopher H. Jenkins
- Chemical, Biological and Radiological Division, Defence Science and Technology Laboratory, Salisbury, Wiltshire, United Kingdom
| | - Andrew E. Scott
- Chemical, Biological and Radiological Division, Defence Science and Technology Laboratory, Salisbury, Wiltshire, United Kingdom
| | - Paul A. O’Neill
- University of Exeter Sequencing Service, Exeter, United Kingdom
| | - Isobel H. Norville
- Chemical, Biological and Radiological Division, Defence Science and Technology Laboratory, Salisbury, Wiltshire, United Kingdom
- Biosciences Department, University of Exeter, Exeter, United Kingdom
| | - Joann L. Prior
- Chemical, Biological and Radiological Division, Defence Science and Technology Laboratory, Salisbury, Wiltshire, United Kingdom
- Biosciences Department, University of Exeter, Exeter, United Kingdom
- Southampton General Hospital, Southampton, United Kingdom
| | - Philip M. Ireland
- Chemical, Biological and Radiological Division, Defence Science and Technology Laboratory, Salisbury, Wiltshire, United Kingdom
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Wilkinson AJ, Ooi N, Finlayson J, Lee VE, Lyth D, Maskew KS, Newman R, Orr D, Ansell K, Birchall K, Canning P, Coombs P, Fusani L, McIver E, Pisco J, Ireland PM, Jenkins C, Norville IH, Southern SJ, Cowan R, Hall G, Kettleborough C, Savage VJ, Cooper IR. Evaluating the druggability of TrmD, a potential antibacterial target, through design and microbiological profiling of a series of potent TrmD inhibitors. Bioorg Med Chem Lett 2023; 90:129331. [PMID: 37187252 DOI: 10.1016/j.bmcl.2023.129331] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Revised: 05/11/2023] [Accepted: 05/12/2023] [Indexed: 05/17/2023]
Abstract
The post-transcriptional modifier tRNA-(N1G37) methyltransferase (TrmD) has been proposed to be essential for growth in many Gram-negative and Gram-positive pathogens, however previously reported inhibitors show only weak antibacterial activity. In this work, optimisation of fragment hits resulted in compounds with low nanomolar TrmD inhibition incorporating features designed to enhance bacterial permeability and covering a range of physicochemical space. The resulting lack of significant antibacterial activity suggests that whilst TrmD is highly ligandable, its essentiality and druggability are called into question.
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Affiliation(s)
- Andrew J Wilkinson
- Infex Therapeutics Ltd, Mereside, Alderley Park, Macclesfield, SK10 4TG, UK.
| | - Nicola Ooi
- Infex Therapeutics Ltd, Mereside, Alderley Park, Macclesfield, SK10 4TG, UK
| | - Jonathan Finlayson
- Infex Therapeutics Ltd, Mereside, Alderley Park, Macclesfield, SK10 4TG, UK
| | - Victoria E Lee
- Infex Therapeutics Ltd, Mereside, Alderley Park, Macclesfield, SK10 4TG, UK
| | - David Lyth
- Infex Therapeutics Ltd, Mereside, Alderley Park, Macclesfield, SK10 4TG, UK
| | - Kathryn S Maskew
- Infex Therapeutics Ltd, Mereside, Alderley Park, Macclesfield, SK10 4TG, UK
| | - Rebecca Newman
- Infex Therapeutics Ltd, Mereside, Alderley Park, Macclesfield, SK10 4TG, UK
| | - David Orr
- Infex Therapeutics Ltd, Mereside, Alderley Park, Macclesfield, SK10 4TG, UK
| | - Keith Ansell
- LifeArc, Accelerator Building, Open Innovation Campus, Stevenage, SG1 2FX, UK
| | - Kristian Birchall
- LifeArc, Accelerator Building, Open Innovation Campus, Stevenage, SG1 2FX, UK
| | - Peter Canning
- LifeArc, Accelerator Building, Open Innovation Campus, Stevenage, SG1 2FX, UK
| | - Peter Coombs
- LifeArc, Accelerator Building, Open Innovation Campus, Stevenage, SG1 2FX, UK
| | - Lucia Fusani
- LifeArc, Accelerator Building, Open Innovation Campus, Stevenage, SG1 2FX, UK
| | - Ed McIver
- LifeArc, Accelerator Building, Open Innovation Campus, Stevenage, SG1 2FX, UK
| | - João Pisco
- LifeArc, Accelerator Building, Open Innovation Campus, Stevenage, SG1 2FX, UK
| | - Philip M Ireland
- CBR division, Dstl Porton Down, Salisbury, Wiltshire, SP4 0JQ, UK
| | | | | | | | - Richard Cowan
- Leicester Institute of Structural and Chemical Biology and Department of Molecular and Cell Biology, Henry Wellcome Building, University of Leicester, Leicester, LE1 7RH, UK
| | - Gareth Hall
- Leicester Institute of Structural and Chemical Biology and Department of Molecular and Cell Biology, Henry Wellcome Building, University of Leicester, Leicester, LE1 7RH, UK
| | | | - Victoria J Savage
- Infex Therapeutics Ltd, Mereside, Alderley Park, Macclesfield, SK10 4TG, UK
| | - Ian R Cooper
- Infex Therapeutics Ltd, Mereside, Alderley Park, Macclesfield, SK10 4TG, UK
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Senior NJ, Sasidharan K, Saint RJ, Scott AE, Sarkar-Tyson M, Ireland PM, Bullifent HL, Rong Yang Z, Moore K, Oyston PCF, Atkins TP, Atkins HS, Soyer OS, Titball RW. An integrated computational-experimental approach reveals Yersinia pestis genes essential across a narrow or a broad range of environmental conditions. BMC Microbiol 2017; 17:163. [PMID: 28732479 PMCID: PMC5521123 DOI: 10.1186/s12866-017-1073-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Accepted: 07/17/2017] [Indexed: 01/07/2023] Open
Abstract
Background The World Health Organization has categorized plague as a re-emerging disease and the potential for Yersinia pestis to also be used as a bioweapon makes the identification of new drug targets against this pathogen a priority. Environmental temperature is a key signal which regulates virulence of the bacterium. The bacterium normally grows outside the human host at 28 °C. Therefore, understanding the mechanisms that the bacterium used to adapt to a mammalian host at 37 °C is central to the development of vaccines or drugs for the prevention or treatment of human disease. Results Using a library of over 1 million Y. pestis CO92 random mutants and transposon-directed insertion site sequencing, we identified 530 essential genes when the bacteria were cultured at 28 °C. When the library of mutants was subsequently cultured at 37 °C we identified 19 genes that were essential at 37 °C but not at 28 °C, including genes which encode proteins that play a role in enabling functioning of the type III secretion and in DNA replication and maintenance. Using genome-scale metabolic network reconstruction we showed that growth conditions profoundly influence the physiology of the bacterium, and by combining computational and experimental approaches we were able to identify 54 genes that are essential under a broad range of conditions. Conclusions Using an integrated computational-experimental approach we identify genes which are required for growth at 37 °C and under a broad range of environments may be the best targets for the development of new interventions to prevent or treat plague in humans. Electronic supplementary material The online version of this article (doi:10.1186/s12866-017-1073-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Nicola J Senior
- College of Life and Environmental Sciences, University of Exeter, Exeter, EX4 4SB, UK
| | - Kalesh Sasidharan
- School of Life Sciences, University of Warwick, Coventry, CV4 7AL, UK
| | - Richard J Saint
- Defence Science Technology Laboratory, Porton Down, Salisbury, SP4 OJQ, UK
| | - Andrew E Scott
- Defence Science Technology Laboratory, Porton Down, Salisbury, SP4 OJQ, UK
| | - Mitali Sarkar-Tyson
- Defence Science Technology Laboratory, Porton Down, Salisbury, SP4 OJQ, UK.,Marshall Centre for Infectious Disease Research and Training, School of Pathology and Laboratory Medicine, University of Western Australia, Perth, WA, 6009, Australia
| | - Philip M Ireland
- Defence Science Technology Laboratory, Porton Down, Salisbury, SP4 OJQ, UK
| | - Helen L Bullifent
- Defence Science Technology Laboratory, Porton Down, Salisbury, SP4 OJQ, UK
| | - Z Rong Yang
- College of Life and Environmental Sciences, University of Exeter, Exeter, EX4 4SB, UK
| | - Karen Moore
- College of Life and Environmental Sciences, University of Exeter, Exeter, EX4 4SB, UK
| | - Petra C F Oyston
- Defence Science Technology Laboratory, Porton Down, Salisbury, SP4 OJQ, UK
| | - Timothy P Atkins
- College of Life and Environmental Sciences, University of Exeter, Exeter, EX4 4SB, UK.,Defence Science Technology Laboratory, Porton Down, Salisbury, SP4 OJQ, UK
| | - Helen S Atkins
- College of Life and Environmental Sciences, University of Exeter, Exeter, EX4 4SB, UK.,Defence Science Technology Laboratory, Porton Down, Salisbury, SP4 OJQ, UK
| | - Orkun S Soyer
- School of Life Sciences, University of Warwick, Coventry, CV4 7AL, UK
| | - Richard W Titball
- College of Life and Environmental Sciences, University of Exeter, Exeter, EX4 4SB, UK.
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Vanaporn M, Sarkar-Tyson M, Kovacs-Simon A, Ireland PM, Pumirat P, Korbsrisate S, Titball RW, Butt A. Trehalase plays a role in macrophage colonization and virulence of Burkholderia pseudomallei in insect and mammalian hosts. Virulence 2017; 8:30-40. [PMID: 27367830 PMCID: PMC5963195 DOI: 10.1080/21505594.2016.1199316] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Revised: 06/01/2016] [Accepted: 06/03/2016] [Indexed: 10/21/2022] Open
Abstract
Trehalose is a disaccharide formed from two glucose molecules. This sugar molecule can be isolated from a range of organisms including bacteria, fungi, plants and invertebrates. Trehalose has a variety of functions including a role as an energy storage molecule, a structural component of glycolipids and plays a role in the virulence of some microorganisms. There are many metabolic pathways that control the biosynthesis and degradation of trehalose in different organisms. The enzyme trehalase forms part of a pathway that converts trehalose into glucose. In this study we set out to investigate whether trehalase plays a role in both stress adaptation and virulence of Burkholderia pseudomallei. We show that a trehalase deletion mutant (treA) had increased tolerance to thermal stress and produced less biofilm than the wild type B. pseudomallei K96243 strain. We also show that the ΔtreA mutant has reduced ability to survive in macrophages and that it is attenuated in both Galleria mellonella (wax moth larvae) and a mouse infection model. This is the first report that trehalase is important for bacterial virulence.
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Affiliation(s)
- Muthita Vanaporn
- College of Life and Environmental Sciences, University of Exeter, Exeter, UK
- Department of Microbiology and Immunology, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | | | - Andrea Kovacs-Simon
- College of Life and Environmental Sciences, University of Exeter, Exeter, UK
| | - Philip M. Ireland
- CBR Division, Defense Science and Technology Laboratory, Salisbury, UK
| | - Pornpan Pumirat
- Department of Microbiology and Immunology, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Sunee Korbsrisate
- Department of Immunology, Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Richard W. Titball
- College of Life and Environmental Sciences, University of Exeter, Exeter, UK
| | - Aaron Butt
- College of Life and Environmental Sciences, University of Exeter, Exeter, UK
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Ford DC, Ireland PM, Bullifent HL, Saint RJ, McAlister EV, Sarkar-Tyson M, Oyston PCF. Construction of an inducible system for the analysis of essential genes in Yersinia pestis. J Microbiol Methods 2014; 100:1-7. [PMID: 24524852 DOI: 10.1016/j.mimet.2014.01.017] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2013] [Revised: 01/20/2014] [Accepted: 01/25/2014] [Indexed: 01/14/2023]
Abstract
Yersinia pestis, a Gram negative bacterium, causes bubonic and pneumonic plague. Emerging antibiotic resistance in clinical isolates is driving a need to develop novel antibiotics to treat infection by this transmissible and highly virulent pathogen. Proteins required for viability, so called essential genes, are attractive potential therapeutic targets, however, confirmation of essentiality is problematic. For the first time, we report the development of a system that allows the rapid determination of Y. pestis gene essentiality through mutagenesis and inducible expression of a plasmid borne copy of the target gene. Using this approach, we have confirmed the uridine monophosphate kinase PyrH as an essential protein in Y. pestis. This methodology and the tools we have developed will allow the confirmation of other putative essential genes in this dangerous pathogen, and facilitate the identification of novel targets for antimicrobial development.
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Affiliation(s)
- D C Ford
- Defence Science and Technology Laboratory, Porton Down, Salisbury, Wiltshire SP4 0JQ, UK.
| | - P M Ireland
- Defence Science and Technology Laboratory, Porton Down, Salisbury, Wiltshire SP4 0JQ, UK
| | - H L Bullifent
- Defence Science and Technology Laboratory, Porton Down, Salisbury, Wiltshire SP4 0JQ, UK
| | - R J Saint
- Defence Science and Technology Laboratory, Porton Down, Salisbury, Wiltshire SP4 0JQ, UK
| | - E V McAlister
- Defence Science and Technology Laboratory, Porton Down, Salisbury, Wiltshire SP4 0JQ, UK
| | - M Sarkar-Tyson
- Defence Science and Technology Laboratory, Porton Down, Salisbury, Wiltshire SP4 0JQ, UK
| | - P C F Oyston
- Defence Science and Technology Laboratory, Porton Down, Salisbury, Wiltshire SP4 0JQ, UK
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7
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Ireland PM, McMahon RM, Marshall LE, Halili M, Furlong E, Tay S, Martin JL, Sarkar-Tyson M. Disarming Burkholderia pseudomallei: structural and functional characterization of a disulfide oxidoreductase (DsbA) required for virulence in vivo. Antioxid Redox Signal 2014; 20:606-17. [PMID: 23901809 PMCID: PMC3901323 DOI: 10.1089/ars.2013.5375] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
AIMS The intracellular pathogen Burkholderia pseudomallei causes the disease melioidosis, a major source of morbidity and mortality in southeast Asia and northern Australia. The need to develop novel antimicrobials is compounded by the absence of a licensed vaccine and the bacterium's resistance to multiple antibiotics. In a number of clinically relevant Gram-negative pathogens, DsbA is the primary disulfide oxidoreductase responsible for catalyzing the formation of disulfide bonds in secreted and membrane-associated proteins. In this study, a putative B. pseudomallei dsbA gene was evaluated functionally and structurally and its contribution to infection assessed. RESULTS Biochemical studies confirmed the dsbA gene encodes a protein disulfide oxidoreductase. A dsbA deletion strain of B. pseudomallei was attenuated in both macrophages and a BALB/c mouse model of infection and displayed pleiotropic phenotypes that included defects in both secretion and motility. The 1.9 Å resolution crystal structure of BpsDsbA revealed differences from the classic member of this family Escherichia coli DsbA, in particular within the region surrounding the active site disulfide where EcDsbA engages with its partner protein E. coli DsbB, indicating that the interaction of BpsDsbA with its proposed partner BpsDsbB may be distinct from that of EcDsbA-EcDsbB. INNOVATION This study has characterized BpsDsbA biochemically and structurally and determined that it is required for virulence of B. pseudomallei. CONCLUSION These data establish a critical role for BpsDsbA in B. pseudomallei infection, which in combination with our structural characterization of BpsDsbA will facilitate the future development of rationally designed inhibitors against this drug-resistant organism.
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Affiliation(s)
- Philip M Ireland
- 1 Defence Science and Technology Laboratory , Porton Down, Salisbury, Wiltshire, United Kingdom
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Ireland PM, LeButt H, Thomas RM, Oyston PCF. A Francisella tularensis SCHU S4 mutant deficient in γ-glutamyltransferase activity induces protective immunity: characterization of an attenuated vaccine candidate. Microbiology (Reading) 2011; 157:3172-3179. [PMID: 21852349 DOI: 10.1099/mic.0.052902-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Francisella tularensis is an intracellular pathogen which causes tularaemia. There is no licensed vaccine currently available for prophylaxis. The γ-glutamyl transpeptidase (GGT) encoded by the ggt gene has been shown to be important for the intracellular survival of F. tularensis. In this study we have constructed a ggt deletion mutant in the highly virulent F. tularensis strain SCHU S4. Characterization of the mutant strain confirmed the function of ggt, and confirmed the role of GGT in cysteine acquisition. The mutant strain was highly attenuated both in vitro and in vivo using murine models of infection. Moreover, we have demonstrated that the attenuated mutant is able to induce protective immunity against an F. tularensis SCHU S4 challenge, and thus may be a candidate for the development of an attenuated vaccine.
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Affiliation(s)
- Philip M Ireland
- Defence Science and Technology Laboratory, Porton Down, Salisbury, Wiltshire SP4 0JQ, UK
| | - Helen LeButt
- Defence Science and Technology Laboratory, Porton Down, Salisbury, Wiltshire SP4 0JQ, UK
| | - Rebecca M Thomas
- Defence Science and Technology Laboratory, Porton Down, Salisbury, Wiltshire SP4 0JQ, UK
| | - Petra C F Oyston
- Defence Science and Technology Laboratory, Porton Down, Salisbury, Wiltshire SP4 0JQ, UK
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Dean RE, Ireland PM, Jordan JE, Titball RW, Oyston PCF. RelA regulates virulence and intracellular survival of Francisella novicida. Microbiology (Reading) 2009; 155:4104-4113. [PMID: 19762448 DOI: 10.1099/mic.0.031021-0] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Analysis of the genome of Francisella tularensis has revealed few regulatory systems, and how the organism adapts to conditions in different niches is poorly understood. The stringent response is a global stress response mediated by (p)ppGpp. The enzyme RelA has been shown to be involved in generation of this signal molecule in a range of bacterial species. We investigated the effect of inactivation of the relA gene in Francisella by generating a mutant in Francisella novicida. Under amino acid starvation conditions, the relA mutant was defective for (p)ppGpp production. Characterization showed the mutant to grow similarly to the wild-type, except that it entered stationary phase later than wild-type cultures, resulting in higher cell yields. The relA mutant showed increased biofilm formation, which may be linked to the delay in entering stationary phase, which in turn would result in higher cell numbers present in the biofilm and reduced resistance to in vitro stress. The mutant was attenuated in the J774A macrophage cell line and was shown to be attenuated in the mouse model of tularaemia, but was able to induce a protective immune response. Therefore, (p)ppGpp appears to be an important intracellular signal, integral to the pathogenesis of F. novicida.
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Affiliation(s)
- R E Dean
- Biomedical Sciences, Dstl Porton Down, Salisbury, Wiltshire SP4 0JQ, UK
| | - P M Ireland
- Biomedical Sciences, Dstl Porton Down, Salisbury, Wiltshire SP4 0JQ, UK
| | - J E Jordan
- Biomedical Sciences, Dstl Porton Down, Salisbury, Wiltshire SP4 0JQ, UK
| | - R W Titball
- School of Biosciences, University of Exeter, Geoffrey Pope Building, Stocker Road, Exeter EX4 4QD, UK
| | - P C F Oyston
- Biomedical Sciences, Dstl Porton Down, Salisbury, Wiltshire SP4 0JQ, UK
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Abstract
In 1991, five different total joint replacement surgeons performed 337 primary total knee replacements and 250 primary total hip replacements. They revised 25 total knee replacements and 73 total hip replacements. The average length of stay was 6.6 days for the primary total knee arthroplasty and 7.5 days for knee revisions. For total hip replacement, average stay was 5.9 days for primary surgery and 6 days for revisions. The operative time required for each of the five surgeons to complete a total knee replacement increased 55%, 3%, 38%, 72% and 38%; whereas for the total hip replacement, time increased 87%, 77%, 84% and 58%. Overall, there was a 41% increase in operating time for revision total knee replacements and a 77% increase for revision total hip replacement. Allowable charges by Medicare in 1993 for a primary knee and hip replacement were $1,298 and $1,363, respectively. Revision total knee replacement increased 24.3% ($1,613) and revision total hip replacement increased 30.8% ($1,782) in the state of Indiana. These figures do not encourage those surgeons who are capable of doing total joint replacements to revise other surgeons' problems.
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Affiliation(s)
- M A Ritter
- Center for Hip and Knee Surgery, Mooresville, Ind. 46158, USA
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