Name: high-throughput parallel sequencing to measure fitness of leptospira interrogans transposon insertion mutants during golden syrian hamster infection
Uploaded: 2017-12-18T12:30:00
Description: Watch this Scientific Journal Video about High-throughput Parallel Sequencing to Measure Fitness of Leptospira interrogans Transposon Insertion Mutants During Golden Syrian Hamster Infection at JoVE.c

Ce travail a été soutenu par un prix de mérite d’affaires des anciens combattants (à D.A.H.) et un Institut National de la santé accorde le R01 AI 034431 (à D.A.H.).

ATTENTION : Des souches pathogènes de Leptospira spp doivent être manipulés sous procédures de confinement de niveau de biosécurité 2 (BSL-2). Portez un équipement de protection individuelle (EPI) approprié doit être porté. Une armoire de biosécurité classe II doit être utilisée pour toutes les manipulations des pathogènes Leptospira spp.
1. création du Transposon bibliothèque mutante15
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Transfert du transposon dans ...

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	<li>Murray, G. L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Genome-wide+transposon+mutagenesis+in+pathogenic+Leptospira+species.">Genome-wide transposon mutagenesis in pathogenic Leptospira species.</a> Infect Immun. 77 (2), 810-816 (2009).</li><li>Adler, B., Lo, M., Seemann, T., Murray, G. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pathogenesis+of+leptospirosis:+the+influence+of+genomics.">Pathogenesis of leptospirosis: the influence of genomics.</a> Vet Microbiol. 153 (1-2), 73-81 (2011).</li><li>Marcsisin, R. A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Use+of+a+high-throughput+screen+to+identify+Leptospira+mutants+unable+to+colonize+the+carrier+host+or+cause+disease+in+the+acute+model+of+infection.">Use of a high-throughput screen to identify Leptospira mutants unable to colonize the carrier host or cause disease in the acute model of infection.</a> J Med Microbiol. 62, 1601-1608 (2013).</li><li>van Opijnen, T., Bodi, K. L., Camilli, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tn-seq:+high-throughput+parallel+sequencing+for+fitness+and+genetic+interaction+studies+in+microorganisms.">Tn-seq: high-throughput parallel sequencing for fitness and genetic interaction studies in microorganisms.</a> Nat Methods. 6 (10), 767-772 (2009).</li><li>van Opijnen, T., Lazinski, D. W., Camilli, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Genome-wide+fitness+and+genetic+interactions+determined+by+Tn-seq,+a+high-throughput+massively+parallel+sequencing+method+for+microorganisms.">Genome-wide fitness and genetic interactions determined by Tn-seq, a high-throughput massively parallel sequencing method for microorganisms.</a> Curr Protoc Microbiol. 36, 1E.3.1-1E.3.24 (2015).</li><li>Troy, E. B., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Understanding+barriers+to+Borrelia+burgdorferi+dissemination+during+infection+using+massively+parallel+sequencing.">Understanding barriers to Borrelia burgdorferi dissemination during infection using massively parallel sequencing.</a> Infect Immun. 81 (7), 2347-2357 (2013).</li><li>Wunder, E. A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Real-time+PCR+reveals+rapid+dissemination+of+Leptospira+interrogans+after+intraperitoneal+and+conjunctival+inoculation+of+hamsters.">Real-time PCR reveals rapid dissemination of Leptospira interrogans after intraperitoneal and conjunctival inoculation of hamsters.</a> Infect Immun. 84 (7), 2105-2115 (2016).</li><li>Lourdault, K., Aviat, F., Picardeau, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Use+of+quantitative+real-time+PCR+for+studying+the+dissemination+of+Leptospira+interrogans+in+the+guinea+pig+infection+model+of+leptospirosis.">Use of quantitative real-time PCR for studying the dissemination of Leptospira interrogans in the guinea pig infection model of leptospirosis.</a> J Med Microbiol. 58, 648-655 (2009).</li><li>Coutinho, M. L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Kinetics+of+Leptospira+interrogans+infection+in+hamsters+after+intradermal+and+subcutaneous+challenge.">Kinetics of Leptospira interrogans infection in hamsters after intradermal and subcutaneous challenge.</a> PLoS Negl Trop Dis. 8 (11), e3307 (2014).</li><li>Athanazio, D. A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Rattus+norvegicus+as+a+model+for+persistent+renal+colonization+by+pathogenic+Leptospira+interrogans.">Rattus norvegicus as a model for persistent renal colonization by pathogenic Leptospira interrogans.</a> Acta Trop. 105 (2), 176-180 (2008).</li><li>Ratet, G., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Live+imaging+of+bioluminescent+Leptospira+interrogans+in+mice+reveals+renal+colonization+as+a+stealth+escape+from+the+blood+defenses+and+antibiotics.">Live imaging of bioluminescent Leptospira interrogans in mice reveals renal colonization as a stealth escape from the blood defenses and antibiotics.</a> PLoS Negl Trop Dis. 8 (12), e3359 (2014).</li><li>Gutierrez, M. G., Yoder-Himes, D. R., Warawa, J. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comprehensive+identification+of+virulence+factors+required+for+respiratory+melioidosis+using+Tn-seq+mutagenesis.">Comprehensive identification of virulence factors required for respiratory melioidosis using Tn-seq mutagenesis.</a> Front Cell Infect Microbiol. 5 (78), (2015).</li><li>Gawronski, J. D., Wong, S. M., Giannoukos, G., Ward, D. V., Akerley, B. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tracking+insertion+mutants+within+libraries+by+deep+sequencing+and+a+genome-wide+screen+for+Haemophilus+genes+required+in+the+lung.">Tracking insertion mutants within libraries by deep sequencing and a genome-wide screen for Haemophilus genes required in the lung.</a> Proc Natl Acad Sci U S A. 106 (38), 16422-16427 (2009).</li><li>Gallagher, L. A., Shendure, J., Manoil, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Genome-scale+identification+of+resistance+functions+in+Pseudomonas+aeruginosa+using+Tn-seq.">Genome-scale identification of resistance functions in Pseudomonas aeruginosa using Tn-seq.</a> MBio. 2 (1), (2011).</li><li>Slamti, L., Picardeau, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Construction+of+a+library+of+random+mutants+in+the+spirochete+Leptospira+biflexa+using+a+mariner+transposon.">Construction of a library of random mutants in the spirochete Leptospira biflexa using a mariner transposon.</a> Methods Mol Biol. 859, (2012).</li><li>Picardeau, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Conjugative+transfer+between+Escherichia+coli+and+Leptospira+spp.+as+a+new+genetic+tool.">Conjugative transfer between Escherichia coli and Leptospira spp. as a new genetic tool.</a> Appl Environ Microbiol. 74 (1), 319-322 (2008).</li><li>Lourdault, K., Matsunaga, J., Haake, D. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=High-throughput+parallel+sequencing+to+measure+fitness+of+Leptospira+interrogans+transposon+insertion+mutants+during+acute+infection.">High-throughput parallel sequencing to measure fitness of Leptospira interrogans transposon insertion mutants during acute infection.</a> PLoS Negl Trop Dis. 10 (11), e0005117 (2016).</li><li>Ellinghausen, H. C., McCullough, W. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nutrition+of+Leptospirapomona+and+growth+of+13+other+serotypes:+Fractionation+of+oleic+albumin+complex+and+a+medium+of+bovine+albumin+and+polysorbate+80.">Nutrition of Leptospirapomona and growth of 13 other serotypes: Fractionation of oleic albumin complex and a medium of bovine albumin and polysorbate 80.</a> Am J Vet Res. 26, 45-51 (1965).</li><li>Johnson, R. C., Harris, V. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Differentiation+of+pathogenic+and+saprophytic+letospires.+I.+Growth+at+low+temperatures.">Differentiation of pathogenic and saprophytic letospires. I. Growth at low temperatures.</a> J Bacteriol. 94 (1), 27-31 (1967).</li><li>Demarre, G., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+new+family+of+mobilizable+suicide+plasmids+based+on+broad+host+range+R388+plasmid+(IncW)+and+RP4+plasmid+(IncPa)+conjugative+machineries+and+their+cognate+Escherichia+coli+host+strains.">A new family of mobilizable suicide plasmids based on broad host range R388 plasmid (IncW) and RP4 plasmid (IncPa) conjugative machineries and their cognate Escherichia coli host strains.</a> Res Microbiol. 156 (2), 245-255 (2005).</li><li>Vallenet, D., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=MicroScope:+a+platform+for+microbial+genome+annotation+and+comparative+genomics.">MicroScope: a platform for microbial genome annotation and comparative genomics.</a> Database (Oxford). , bap021 (2009).</li><li>Goodman, A. L., Wu, M., Gordon, J. I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Identifying+microbial+fitness+determinants+by+insertion+sequencing+using+genome-wide+transposon+mutant+libraries.">Identifying microbial fitness determinants by insertion sequencing using genome-wide transposon mutant libraries.</a> Nat. Protocols. 6 (12), 1969-1980 (2011).</li><li>Miller, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Spirochetes in body fluids and tissues manual of investigative methods. , 22-23 (1971).</li><li>Ristow, P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+OmpA-like+protein+Loa22+is+essential+for+leptospiral+virulence.">The OmpA-like protein Loa22 is essential for leptospiral virulence.</a> PLoS Pathog. 3 (7), (2007).</li><li>Croda, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Targeted+mutagenesis+in+pathogenic+Leptospira+species:+disruption+of+the+LigB+gene+does+not+affect+virulence+in+animal+models+of+leptospirosis.">Targeted mutagenesis in pathogenic Leptospira species: disruption of the LigB gene does not affect virulence in animal models of leptospirosis.</a> Infect Immun. 76 (12), 5826-5833 (2008).</li><li>Haake, D. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hamster+model+of+leptospirosis.">Hamster model of leptospirosis.</a> Curr Protoc Microbiol. 12, 2 (2006).</li><li>Giardine, B., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Galaxy:+a+platform+for+interactive+large-scale+genome+analysis.">Galaxy: a platform for interactive large-scale genome analysis.</a> Genome Res. 15 (10), 1451-1455 (2005).</li><li>Goecks, J., Nekrutenko, A., Taylor, J., Galaxy, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Galaxy:+a+comprehensive+approach+for+supporting+accessible,+reproducible,+and+transparent+computational+research+in+the+life+sciences.">Galaxy: a comprehensive approach for supporting accessible, reproducible, and transparent computational research in the life sciences.</a> Genome Biol. 11 (8), R86 (2010).</li><li>Blankenberg, D., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Galaxy:+a+web-based+genome+analysis+tool+for+experimentalists.">Galaxy: a web-based genome analysis tool for experimentalists.</a> Curr Protoc Mol Biol. (Chapter 19), 11-21 (2010).</li><li>Afgan, E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+Galaxy+platform+for+accessible,+reproducible+and+collaborative+biomedical+analyses:+2016+update.">The Galaxy platform for accessible, reproducible and collaborative biomedical analyses: 2016 update.</a> Nucleic Acids Res. 8 (44), (2016).</li><li>McCoy, K. M., Antonio, M. L., van Opijnen, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=MAGenTA;+a+Galaxy+implemented+tool+for+complete+Tn-Seq+analysis+and+data+visualization.">MAGenTA; a Galaxy implemented tool for complete Tn-Seq analysis and data visualization.</a> Bioinformatics. , 1367 (2017).</li><li>Langmead, B., Trapnell, C., Pop, M., Salzberg, S. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ultrafast+and+memory-efficient+alignment+of+short+DNA+sequences+to+the+human+genome.">Ultrafast and memory-efficient alignment of short DNA sequences to the human genome.</a> Genome Biol. 10 (3), R25 (2009).</li><li>Kamp, H. D., Patimalla-Dipali, B., Lazinski, D. W., Wallace-Gadsden, F., Camilli, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Gene+fitness+landscapes+of+Vibrio+cholerae+at+important+stages+of+its+life+cycle.">Gene fitness landscapes of Vibrio cholerae at important stages of its life cycle.</a> PLoS Pathog. 9 (12), e1003800 (2013).</li><li>Poggi, D., Oliveira de Giuseppe, P., Picardeau, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Antibiotic+resistance+markers+for+genetic+manipulations+of+Leptospira+spp.">Antibiotic resistance markers for genetic manipulations of Leptospira spp.</a> Appl Environ Microbiol. 76 (14), 4882-4885 (2010).</li><li>van Opijnen, T., Camilli, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Transposon+insertion+sequencing:+a+new+tool+for+systems-level+analysis+of+microorganisms.">Transposon insertion sequencing: a new tool for systems-level analysis of microorganisms.</a> Nat Rev Microbiol. 11 (7), 435-442 (2013).</li><li>Pappas, C. J., Picardeau, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Control+of+gene+expression+in+Leptospira+spp.+by+Transcription+activator-like+effectors+demonstrates+a+potential+role+for+LigA+and+LigB+in+Leptospira+interrogans+virulence.">Control of gene expression in Leptospira spp. by Transcription activator-like effectors demonstrates a potential role for LigA and LigB in Leptospira interrogans virulence.</a> Appl Environ Microbiol. 81 (22), 7888-7892 (2015).</li><li>Koskiniemi, S., Sun, S., Berg, O. G., Andersson, D. I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Selection-driven+gene+loss+in+bacteria.">Selection-driven gene loss in bacteria.</a> PLoS Genet. 8 (6), e1002787 (2012).</li><li>Troy, E. B., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Global+Tn-seq+analysis+of+carbohydrate+utilization+and+vertebrate+infectivity+of+Borrelia+burgdorferi.">Global Tn-seq analysis of carbohydrate utilization and vertebrate infectivity of Borrelia burgdorferi.</a> Mol Microbiol. 101 (6), 1003-1023 (2016).</li><li>Ramsey, M. E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+high-throughput+genetic+screen+identifies+previously+uncharacterized+Borrelia+burgdorferi+genes+important+for+resistance+against+reactive+oxygen+and+nitrogen+species.">A high-throughput genetic screen identifies previously uncharacterized Borrelia burgdorferi genes important for resistance against reactive oxygen and nitrogen species.</a> PLoS Negl Trop Dis. 13 (2), e1006225 (2017).</li></ol>

Bien que les résultats de notre expérience pilote pour hamster contestée par voie intrapéritonéale avec 42 L. interrogans mutants sont présentés17, gageons que plus grandes piscines de mutants peuvent être projetés par Tn-suiv. Parce que la fréquence des transconjugants est faible (100-200 transconjugants/accouplement), plusieurs accouplements sont nécessaires pour générer un nombre suffisant de mutants pour les grandes expériences de Tn-Seq. Maintenir un grand nombre de mut...

Identification des gènes de virulence pour certaines bactéries, comme Leptospira spp., est difficile en raison du nombre limité d’outils génétiques disponibles. Une approche couramment utilisée est la création d’une collection de mutants par mutagenèse aléatoire transposon, suivie de l’identification du site d’insertion dans chaque mutant et test de virulence des mutants de transposon individuels dans un modèle animal. Cette approche est longue et coûteuse et nécessite un grand nombre d’animaux.
Lorsque la mutagénèse aléatoire a été d’abord développé pour le pathogène Leptospira interrogans, gènes impliqués dans la virulence ont été identifiés en testant différents mutants dans un modèle animal1. Mutants ont été sélectionnés selon des critères comme leurs rôles potentiels dans la signalisation ou la motilité ou leur prédit la membrane externe ou surface emplacement. Comme la majorité des leptospires gènes codent pour des protéines hypothétiques de fonction inconnue2, sélection des mutants basé sur ces limites de critères la capacité à découvrir des gènes de virulence de leptospires roman.
Plus récemment, piscines de mutants de transposon L. interrogans ont été examinés pour l’agent infectieux dans les modèles3hamster et souris. Chaque animal a été contestée avec une piscine de 10 mutants. Infectiosité d’un mutant a été marquée comme étant positif s’il a été détecté par PCR des cultures obtenues à partir de sang et les reins. Test de PCR a été laborieux car il exigeait une réaction de PCR individuelle pour chaque mutant dans la piscine. Parce que la fréquence de chaque mutant dans les cultures n’avait pas été évaluée, l’approche était biaisée vers l’identification des mutants très atténués.
Nous décrivons un transposon séquençage (Tn-Seq) technique, comme une stratégie pour dépister plus efficacement les gènes de virulence. TN-seq consistant en la création d’une bibliothèque de mutants par mutagénèse du transposon suivie par séquençage parallèle massive4,5,6. Brièvement, transposon mutants sont mis en commun, inoculés dans animaux et par la suite récupérés de différents organes (sortie piscines). L’ADN de la piscine de sortie est extraite et digéré par les enzymes de restriction ou cisaillée par sonication. Deux cycles de PCR ciblant les jonctions des sites d’insertion de transposon sont effectuées. Cette étape permet l’ajout de l’adaptateur nécessaire pour le séquençage. Les produits PCR obtenus sont analysés par séquençage haut-débit pour identifier le site d’insertion de transposon de chaque mutant de la piscine ainsi que de leur abondance relative, qui est comparé à la composition initiale du bassin de mutant.
Le principal avantage de cette approche est la capacité à l’écran simultanément un grand nombre de mutants avec un petit nombre d’animaux. TN-Seq n’exige pas la connaissance préalable des sites d’insertion de transposon qui augmente les chances de découvrir des nouveaux Leptospira-certains gènes impliqués dans la virulence avec moins de temps et une plus grande efficacité. Parce que le fardeau de leptospires dans les tissus est relativement élevée en rongeur modèles susceptibles d’être mortelles infections (typiquement 104 à 108 bactéries/g de tissu)7,8,9 , ainsi que dans des hôtes réservoirs 10,11, les tissus peuvent être analysés directement sans avoir à la culture, réduire les biais en raison de la croissance in vitro .
Dans les études de Tn-Seq avec la plupart des bactéries pathogènes décrites à ce jour, la haute fréquence de mutagenèse insertionnelle permis infection avec grandes piscines contenant des mutants ayant collectivement plusieurs insertions transposon rapprochés au sein de chaque gène4 ,12,13,14. TN-Seq a également été développé pour une bactérie dont la fréquence de la mutagénèse est beaucoup inférieur6. Avec Leptospira, une bibliothèque de mutants de transposons peut être générée en introduisant le transposon sur un plasmide mobilisable par conjugaison tel que décrit par Slamti et al.15. Toutefois, la fréquence de la mutagénèse transposon de L. interrogans est faible. Lorsque le transposon Himar1 a été introduit dans un plasmide conjugatif, la fréquence de transconjuguant a été signalée comme seuls 8,5 x 10-8 par destinataire de cellules souche de L. interrogans16 Lai et est susceptible d’être de même pauvre avec la plupart des autres souches de L. interrogans. Le protocole décrit ici est en partie basé sur conçu pour Borrelia burgdorferi, dont la fréquence de la mutagénèse insertionnelle transposon est également faible6.
Pour notre expérience pilote avec le protocole17, nous avons mené mutagénèse du transposon avec L. interrogans serovar Manilae souche L495 en raison du succès des autres groupes à isoler des mutants d’insertion de transposon dans la souche ainsi que sa faible DL50 (dose létale) pour virulence1. Nous avons projeté 42 mutants par Tn-Seq et identifié plusieurs candidats mutants défectueux dans la virulence, dont deux avec insertions dans un gène de l’adénylate cyclase du candidat. Une évaluation individuelle des deux mutants chez les hamsters ont confirmé qu’ils étaient déficients en virulence17.

<table>
	<tbody>
		<tr>
			<td>Kanamycin sulfate from Streptomyces kanamyceticus</td>
			<td>Sigma-Aldrich</td>
			<td>K4000</td>
			<td></td>
		</tr>
		<tr>
			<td>2,6-diaminopimelic acid</td>
			<td>Sigma-Aldrich</td>
			<td>D1377</td>
			<td></td>
		</tr>
		<tr>
			<td>Spectinomycin dihydrochloride pentahydrate</td>
			<td>Sigma-Aldrich</td>
			<td>S4014</td>
			<td></td>
		</tr>
		<tr>
			<td>Axio Lab A1 microscope with a darkfieldcondenser</td>
			<td>Zeiss</td>
			<td>490950-001-000</td>
			<td></td>
		</tr>
		<tr>
			<td>DNeasy blood and tissue kit</td>
			<td>Qiagen</td>
			<td>69504/69506</td>
			<td></td>
		</tr>
		<tr>
			<td>MinElute PCR Purification</td>
			<td>Qiagen</td>
			<td>28004/28006</td>
			<td></td>
		</tr>
		<tr>
			<td>QIAquick PCR purification kit</td>
			<td>Qiagen</td>
			<td>28104/28106</td>
			<td></td>
		</tr>
		<tr>
			<td>Model 505 Sonic Dismembrator</td>
			<td>Fisher Scientific</td>
			<td>FB-505</td>
			<td></td>
		</tr>
		<tr>
			<td>2.5&#34; Cup horn</td>
			<td>Fisher Scientific</td>
			<td>FB-4625</td>
			<td></td>
		</tr>
		<tr>
			<td>Bead Ruptor 24</td>
			<td>Omni International</td>
			<td>19-010</td>
			<td>Step 3.1.2.4</td>
		</tr>
		<tr>
			<td>Terminal deoxynucleotidyl transferase</td>
			<td>Promega</td>
			<td>M828C</td>
			<td></td>
		</tr>
		<tr>
			<td>Master mix Phusion</td>
			<td>Thermo Scientific</td>
			<td>F531</td>
			<td>Preparation of genomic libraries, step 3.4.</td>
		</tr>
		<tr>
			<td>DreamTaq Master Mix</td>
			<td>Thermo Scientific</td>
			<td>K9011/K9012</td>
			<td>Identification of the transposon insertion site, step 1.2.</td>
		</tr>
		<tr>
			<td>dCTP</td>
			<td>Thermo Scientific</td>
			<td>R0151</td>
			<td></td>
		</tr>
		<tr>
			<td>ddCTP</td>
			<td>Affymetrix/ USBProducts</td>
			<td>77112</td>
			<td></td>
		</tr>
		<tr>
			<td>T100 Thermal cycler</td>
			<td>BioRad</td>
			<td>1861096</td>
			<td></td>
		</tr>
		<tr>
			<td>Qubit 2.0 fluorometer</td>
			<td>Invitrogen</td>
			<td>Q32866</td>
			<td>step 3.6.</td>
		</tr>
		<tr>
			<td>Qubit dsDNA HS assay kit</td>
			<td>Invitrogen</td>
			<td>Q32851/Q32854</td>
			<td>step 3.6.</td>
		</tr>
		<tr>
			<td>Qubit assay tubes</td>
			<td>life technologies</td>
			<td>Q32856</td>
			<td>step 3.6.</td>
		</tr>
		<tr>
			<td>PBS pH 7.2 (1X)</td>
			<td>Gibco</td>
			<td>20012-027 20012-050</td>
			<td></td>
		</tr>
		<tr>
			<td>Disposable scalpel No10</td>
			<td>Feather</td>
			<td>2975#10</td>
			<td></td>
		</tr>
		<tr>
			<td>Plastic K2 EDTA 2 ml tubes</td>
			<td>BD vacutainer</td>
			<td>367841</td>
			<td></td>
		</tr>
		<tr>
			<td>syringe U-100 with 26G x &#189;&#8221; needle</td>
			<td>BD vacutainer</td>
			<td>329652</td>
			<td>IP challenge, step 2.2.1.</td>
		</tr>
		<tr>
			<td>3 mL Luer-Lok tip syringe</td>
			<td>BD vacutainer</td>
			<td>309657</td>
			<td>Cardiac puncture, step 2.4.2.</td>
		</tr>
		<tr>
			<td>25G X 5/8&#8221; needle</td>
			<td>BD vacutainer</td>
			<td>305901</td>
			<td>Cardiac puncture, step 2.4.2.</td>
		</tr>
		<tr>
			<td>25 mm fritted glass base with stopper</td>
			<td>EMD Millipore</td>
			<td>XX1002502</td>
			<td>Filtration unit system, step 1.1.7.</td>
		</tr>
		<tr>
			<td>25 mm aluminum spring clamp</td>
			<td>EMD Millipore</td>
			<td>XX1002503</td>
			<td>Filtration unit system, step 1.1.7.</td>
		</tr>
		<tr>
			<td>15 ml borosilcate glass funnel</td>
			<td>EMD Millipore</td>
			<td>XX1002514</td>
			<td>Filtration unit system, step 1.1.7.</td>
		</tr>
		<tr>
			<td>125 ml side-arm Erlenmeyer flask</td>
			<td>EMD Millipore</td>
			<td>XX1002505</td>
			<td>Filtration unit system, step 1.1.7.</td>
		</tr>
		<tr>
			<td>Acetate-cellulose filter VVPP (pore size 0.1 mm; diameter 25 mm)</td>
			<td>EMD Millipore</td>
			<td>VVLP02500</td>
			<td></td>
		</tr>
	</tbody>
</table>

high-throughput parallel sequencing to measure fitness of leptospira interrogans transposon insertion mutants during golden syrian hamster infection

Dans ce manuscrit, les auteurs décrivent un transposon séquençage (Tn-Seq) technique pour identifier et quantifier des mutants de Leptospira interrogans altérés de remise en forme au cours de l’infection de hamsters syriens dorés. TN-Seq combine la mutagénèse aléatoire transposon avec la puissance de la technologie de séquençage haut-débit. Animaux est mis au défi avec une piscine de mutants transposon (entrée piscine), suivie de la récolte du sang et des tissus quelques jours plus tard afin d’identifier et de quantifier le nombre de mutants dans chaque organe (sortie piscines). Les piscines de sortie sont comparés à la piscine d’entrée afin d’évaluer l’aptitude en vivo de chaque mutant. Cette approche permet le dépistage d’une grande piscine de mutants dans un nombre limité d’animaux. Avec des modifications mineures, ce protocole peut être effectué avec n’importe quel modèle animal de la leptospirose, modèles hôte réservoir comme les rats et les infections aiguës comme les hamsters, ainsi que des études in vitro . TN-Seq fournit un outil puissant à l’écran pour des mutants présentant des défauts de remise en forme in vivo et in vitro .

Création d’une bibliothèque de mutants de transposon dans L. interrogans par conjugaison nécessite une unité de filtration, comme illustré à la Figure 1. Nous avons récupéré des transconjugants 100-200 de chaque croisement.
Le site d’insertion de transposon est identifié dans chaque mutant par séquençage du produit PCR généré par PCR semi aléatoire qui cible à la fin du...

Watch this Scientific Journal Video about High-throughput Parallel Sequencing to Measure Fitness of Leptospira interrogans Transposon Insertion Mutants During Golden Syrian Hamster Infection at JoVE.c

High-throughput Parallel Sequencing to Measure Fitness of Leptospira interrogans Transposon Insertion Mutants During Golden Syrian Hamster Infection

Nous décrivons ici une technique qui associe une mutagenèse par transposon séquençage haut-débit pour identifier et quantifier des mutants de leptospires transposon dans les tissus après une contestation des hamsters. Ce protocole peut être utilisé à des mutants de l’écran de survie et de la diffusion chez les animaux et peut également être appliqué à des études in vitro .

Haut débit séquençage parallèle à la mesure de remise en forme de Leptospira interrogans Transposon Insertion Mutants durant Golden syrien Hamster Infection

In this manuscript, we describe a transposon sequencing (Tn-Seq) technique to identify and quantify Leptospira interrogans mutants altered in fitness ...

The overall goal of this high-throughput transposon sequencing technique is to identify and quantify transposon mutants with in vivo and in vitro fitness defects, and thereby, identify Leptospira genes involved in virulence. This method can help answer key questions in the Leptospira field, such as identifying genes involved in colonization, dissemination, and survival of the bacteria in the host. The main advantage of this technique is that a large number of mutants can be screened with a limited number of animals.Though this method was designed to examine the fitness of Leptospira interrogans mutants in the hamster model with acute leptospirosis, it can also be applied through a chronic infection models, in vitro studies, and other strains of Leptospira. Demonstrating the procedure will be Kritel Lourdault and Karen Evangelista, both post-docs from my laboratory. First, assemble a filtration unit.Place the base on a 125 milliliter side arm Erlenmeyer flask. Position an acetate cellulose filter at the base and clamp a funnel onto the base. Connect the filtration unit to a vacuum system.Next, add five milliliters of Leptospira culture and 0.5 milliliters of E.coli culture into the funnel. Turn on the vacuum to filter the solution. Then place the filter with bacteria-side up onto an EMJH plate, supplemented with DAP.Incubate the plate at 30 degrees Celsius over night. The next day, transfer the filter into a 15 milliliter tube containing one milliliter of EMJH, and vortex the tube for 10 seconds to release the bacteria in the suspension. Then spread the suspension onto five EMJH plates, supplemented with kanamycin using glass beads or a spreader.Wrap the plates in parafilm and incubate them upside down at 30 degrees Celsius until colonies are visible. When colonies are visible, collect and transfer them individually into three milliliters of EMJH containing kanamycin. Then incubate the tubes at 30 degrees Celsius with 150 rpm agitation for seven to 10 days, or to a density of 100 million cells per milliliter.To identify the transposon insertion site, perform nested PCRs. First, prepare the mix for the first PCR. Then, add the samples from culture to the PCR mixes.After running the first reaction, prepare the mix for the second PCR. Add two microliters of PCR product from the first PCR to the complete the reaction mixes. After running the PCR, examine the products on an agarose gel.Proceed by sequencing the products to determine the transposon insertion site. To begin the animal experiment, first grow individual mutants in EMJH, supplemented with kanamycin. Then determine the culture densities using a dark field microscope.Dilute each cultured mutant strain in EMJH to the same density. Then, pool an equal volume of all the mutants to make the input pool. Now challenge the animals as described in the text protocol.The number of animals required depends on the size of the input pool. Be sure to consult a biostatistician to determine the number of animals to inoculate. Allow the infection to develop for four days, then harvest blood and tissues as described in the text protocol.To extract the DNA from the blood sample, use a commercial extraction kit. For tissue, dice 50 to 80 milligrams of tissue into one millimeter cubes. Then, transfer the diced tissues to a screw cap tube and weigh them on a precision balance.Next, add 500 microliters of sterile PBS into the tube. Homogenize it using a disrupter for one minute. Then use a volume corresponding to 25 milligrams of tissue to extract the DNA.Use a commercial kit according to the manufacturer's instructions. Dilute the DNA in 100 microliters of elution buffer. Next, transfer 50 microliters of extracted DNA into a 1.5 milliliter microcentrifuge tube.Then shear the DNA. Place the tube into a sonicator cup horn filled with water at four degrees Celsius. Run the sonicator for three minutes while wearing ear protection.Next, load 2.5 microliters of the sheared DNA into a 2%agarose gel to confirm that most of the DNA fragments are under 600 base pairs. Next, prepare the reaction mix to add cytosine tails to the DNA fragments. Incubate the reaction for an hour at 37 degrees Celsius.Then, inactivate the enzyme by increasing the temperature to 75 degrees Celsius for 20 minutes. When the reaction is done, clean it up using a PCR purification kit and elute the DNA with 12 microliters of elution buffer. Run two PCRs to create the genomic libraries.For the first PCR, prepare mixes with TnkN3 and olj376 primers. Primer TnkN3 is specific to the transposon and primer olj376 is specific to the C-tail. For each sample, combine 22 microliters of mix with three microliters of C-tailed purified DNA.Then, run the PCR as described in the text protocol. For the second PCR, use one microliter of the first PCR product as a template. For primers, use pMargent2 to target the transposon and use the IP primers.The IP primers each have a six base pair barcode and specific sequences recognizable by the next generation sequencing platform. Next run out three microliters of the second PCR products on a 2%agarose gel. The library should show a smear with the majority of the signal between 200 to 600 base pairs, and no amplification should be observable in the control reaction.Next, clean the genomic libraries with a PCR purification kit and elute the DNA with 30 microliters of elution buffer. Then measure the DNA concentration with a fluorometer. Now, calculate the volume of each library needed for 15 to 20 nanograms of DNA.Mix the libraries and determine the DNA molar concentration in the pool, using a publicly available calculator. Now send the pooled genomic libraries out for high-throughput sequencing. Later, process the FASTQ files obtained from sequencing using open source software and analyze the results.Eight hamsters were challenged with one milliliter of pooled transposon mutants and the infection was allowed to develop for four days. After extracting the DNA collected from these hamsters'livers, it was sheared and characterized on an agarose gel. Most of the fragments were between 200 and 600 base pairs.After adding C-tail to the sheared DNA, PCRs were used to prepare genomic libraries. Electrophoresis was performed to confirm the size of the PCR products. The size of most of the PCR products was between 200 and 600 base pairs.After processing the sequencing reads, the output/input ratios were determined using the transposon sequencing approach. As expected, mutants known to be virulent, such as flaA1 and IlgB do not show any change in fitness. In contrast, mutants known to be attenuated, such as loa22 show a decrease in fitness.Mutants with a reduced in vivo fitness level were identified, such as lic12327. Follow up experimentation showed the virulence of these mutants to be attenuated in hamsters. After watching this video, you should have a good understanding of how to generate genomic DNA libraries in order to quantify and identify mutants with altered in vivo fitness.After mutants with in vivo fitness defects are identified, they can be tested individually in hamsters to determine if their virulence is attenuated. Don't forget that Leptospira interrogans can be lethal and must be handled using BSL2 containment. Personal protective equipment including gloves and a lab coat must be worn while handling the bacteria.

Research

JoVE Journal

Immunology and Infection

High-throughput Parallel Sequencing to Measure Fitness of Leptospira interrogans Transposon Insertion Mutants During Golden Syrian Hamster Infection

High-throughput Detection Method for Influenza Virus

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Génération et multi-phénotypique criblage à haut contenu de<em&gt; Coxiella burnetii</em&gt; Mutants de transposon

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Creation of a Dense Transposon Insertion Library Using Bacterial Conjugation in Enterobacterial Strains Such As Escherichia Coli or Shigella flexneri

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Transposon mutagenesis is a method that allows gene disruption via the random genomic insertion of a piece of DNA called a transposon. The protocol below ...

Replication of the Ordered, Nonredundant Library of Pseudomonas aeruginosa strain PA14 Transposon Insertion Mutants

Replication of the Ordered, Nonredundant Library of Pseudomonas aeruginosa strain PA14 Transposon Insertion Mutants

Réplication de l’ordonné, bibliothèque non redondante de la souche Pseudomonas aeruginosa PA14 Transposon Mutants d’Insertion

Pseudomonas aeruginosa is a phenotypically and genotypically diverse and adaptable Gram-negative bacterium ubiquitous in human environments. P. aeruginosa ...

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Un test haut débit pour évaluer et quantifier les neutrophiles piège extracellulaire Formation

Neutrophil extracellular traps (NETs) are immunogenic extracellular DNA structures that can be released by neutrophils upon a wide variety of triggers. ...

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A High-throughput Shigella-specific Bactericidal Assay

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Serum bactericidal assays (SBAs) measure the functional activity of antibodies and have been used for many decades. SBAs directly measure antibody killing ...

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Streptococcus pneumoniae serotype 1 remains a huge problem in low-and-middle income countries, particularly in sub-Saharan Africa. Despite its importance, ...