- The Institute
- Travel & Vaccines
- Alumni & Friends
Leishmania parasites are the causative agents of diseases ranging from self-healing cutaneous lesions known as Oriental Sore to the lethal visceral leishmaniasis known as Kala-Azar. According to WHO figures, more than 12 million humans are currently infected, with 2 million new infections per year. Leishmaniasis exists in 88 countries on four continents and is a major, compounding complication in HIV infections.
The parasites are unicellular microorganisms that are transmitted to mammals, including humans, by blood-feeding sandflies. They infect and destroy the macrophages of the mammalian immune systems, thereby causing varying forms of immune pathologies.
No vaccination exists against Leishmania infections. Protection is afforded by insect repellents, appropriate clothing, and the use of repellent-treated bed nets. First line drugs against leishmaniasis have varying efficacy depending on the species and the endemic regions, requiring the development of new therapeutic strategies.
Heat shock proteins are traditionally seen as protecting against environmental stress, e.g. non-physiological temperatures, acidic milieu and reactive oxygen species. In the Leishmania parasites, heat shock proteins have evolved according to the needs of their life cycle.
The chaperones HSP100 and Cyclophilin 40 are essential for the intracellular survival of the parasites inside their macrophage host cells, the former by affecting the immune modulation of the mammalian host.
HSP23 is required for the survival of temperatures > 34°C and for resistance against acidic milieu and metalloid compounds, the latter being a mainstay of anti-Leishmania therapy.
Cochaperones Sti1 and SGT are essential for viability, while cochaperones P23 and Aha1 affect the ATPase of the HSP90 chaperone.
We currently investigate how Leishmania copes with the loss of the HSP23 gene and analyse genome alterations that correlate with the gene loss.
Leishmania parasites undergo a shape change when transmitted from sandflies to mammals: spindle shaped insect forms, promastigotes, transform into ovoid amastigotes inside their target cells, macrophages. This process is critical for parasite survival and pathogenicity because only the amastigotes are able to colonise macrophages. The differentiation can be mimicked by the pharmacological inhibition of a key protein, the 90 kD heat shock protein (HSP90).
New systems biology strategies, e.g. ribosome profiling-based, genome-wide quantification of protein synthesis, allowed us to investigate the processes induced during stage differentiation, and we found that i) stage-specific protein synthesis is regulated at the level of translation, ii) inhibition of HSP90 indeed induces the synthesis of several groups of amastigote-specific proteins, and iii) quantitative RNA analysis cannot predict protein synthesis rates.
We are currently looking into the implications of elevated synthesis of two induced protein groups, histones and ribosomal proteins, determining their impact on chromatin structure and selective protein synthesis, respectively.
Moreover, we investigate the roles of the mitochondrial and ER-specific HSP90 family members in the context of life cycle control and stress tolerance.
Leishmania donovani 90 kD Heat Shock Protein - Impact of Phosphosites on Parasite Fitness, Infectivity and Casein Kinase Affinit
Antje Hombach-Barrigah, Katharina Bartsch, Despina Smirlis, Heidi Rosenqvist, Andrea MacDonald, Florence Dingli, Damaris Loew, Gerald F. Späth, Najma Rachidi, Martin Wiese, Joachim Clos
Sci Rep (2019) 9, 5074
Ribosome profiling reveals HSP90 inhibitor effects on stage-specific protein synthesis in Leishmania donovani.
Bifeld E, Lorenzen S, Bartsch K, Vasquez J-J, Siegel TN, Clos J.
mSystems (2018) 3:e00214-18
Geographical sequence variability in the Leishmania major virulence factor P46
Eugenia Bifeld, Mareike Chrobak, Gabi Schönian, Ulrike Schleicher, and Joachim Clos
Infect Genet Evol 30 (2015), 195-205
ARM58 Overexpression Reduces Intracellular Antimony Concentration in Leishmania infantum.
Schäfer, C., Tejera Nevado, P., Zander, D., and Clos, J.
Antimicrob. Agents Chemother. 2014, 58(3):1565.
A small heat shock protein is essential for thermotolerance and intracellular survival of Leishmania donovani
Antje Hombach, Gabi Ommen, Andrea MacDonald, and Joachim Clos
J Cell Science 127 (2014), 4762-4773
Gene Replacement by Homologous Recombination
Zirpel, H. Clos, J.
Methods Mol Biol (2019) 1971, 169-188
Cosmid Library Construction and Functional Cloning
Clos, J. Zander-Dinse, D.
Methods Mol Biol (2019) 1971, 123-140
Generation of Bone Marrow-Derived Macrophages for In Vitro Infection Experiments
Methods Mol Biol (2019) 1971, 237-247
Quantification of Intracellular Leishmania spp. Using Real-Time Quantitative PCR (qPCR)
Methods Mol Biol (2019) 1971, 249-263
Pharmacological Validation of N-Myristoyltransferase as a Drug Target in Leishmania donovani
Corpas-Lopez, V. Moniz, S. Thomas, M. Wall, R. J. Torrie, L. S. Zander-Dinse, D. Tinti, M. Brand, S. Stojanovski, L. Manthri, S. Hallyburton, I. Zuccotto, F. Wyatt, P. G. De Rycker, M. Horn, D. Ferguson, M. A. J. Clos, J. Read, K. D. Fairlamb, A. H. Gilbert, I. H. Wyllie, S.
ACS Infect Dis (2019) 5, 111-122
Accelerating Drug Discovery Efforts for Trypanosomatidic Infections Using an Integrated Transnational Academic Drug Discovery Platform
Moraes, C. B. Witt, G. Kuzikov, M. Ellinger, B. Calogeropoulou, T. Prousis, K. C. Mangani, S. Di Pisa, F. Landi, G. Iacono, L. D. Pozzi, C. Freitas-Junior, L. H. Dos Santos Pascoalino, B. Bertolacini, C. P. Behrens, B. Keminer, O. Leu, J. Wolf, M. Reinshagen, J. Cordeiro-da-Silva, A. Santarem, N. Venturelli, A. Wrigley, S. Karunakaran, D. Kebede, B. Pohner, I. Muller, W. Panecka-Hofman, J. Wade, R. C. Fenske, M. Clos, J. Alunda, J. M. Corral, M. J. Uliassi, E. Bolognesi, M. L. Linciano, P. Quotadamo, A. Ferrari, S. Santucci, M. Borsari, C. Costi, M. P. Gul, S.
SLAS Discov 24, 346-361
Discovery of a benzothiophene-flavonol halting miltefosine and antimonial drug resistance in Leishmania parasites through the application of medicinal chemistry, screening and genomics
Borsari, C. Jimenez-Anton, M. D. Eick, J. Bifeld, E. Torrado, J. J. Olias-Molero, A. I. Corral, M. J. Santarem, N. Baptista, C. Severi, L. Gul, S. Wolf, M. Kuzikov, M. Ellinger, B. Reinshagen, J. Witt, G. Linciano, P. Tait, A. Costantino, L. Luciani, R. Tejera Nevado, P. Zander-Dinse, D. Franco, C. H. Ferrari, S. Moraes, C. B. Cordeiro-da-Silva, A. Ponterini, G. Clos, J. Alunda, J. M. Costi, M. P.
Eur J Med Chem 183, 111676
Leishmania donovani 90 kD Heat Shock Protein - Impact of Phosphosites on Parasite Fitness, Infectivity and Casein Kinase Affinity
Hombach-Barrigah, A. Bartsch, K. Smirlis, D. Rosenqvist, H. MacDonald, A. Dingli, F. Loew, D. Spath, G. F. Rachidi, N. Wiese, M. Clos, J.
Sci Rep 9, 5074
Leishmania - Methods and Protocols
Clos, J. ed.
Methods in Molecular Biology (2019) 1971, 1-368
Molecular Preadaptation to Antimony Resistance in Leishmania donovani on the Indian Subcontinent
Dumetz, F. Cuypers, B. Imamura, H. Zander, D. D'Haenens, E. Maes, I. Domagalska, M. A. Clos, J. Dujardin, J. C. De Muylder, G.
mSphere 3, 10.1128/mSphere.00548-17
Ribosome Profiling Reveals HSP90 Inhibitor Effects on Stage-Specific Protein Synthesis in Leishmania donovani
Bifeld, E. Lorenzen, S. Bartsch, K. Vasquez, J. J. Siegel, T. N. Clos, J.
mSystems 3, 10.1128/mSystems.00214-18
Hsp90 Inhibitors radicicol and geldanamycin have opposing effects onLeishmaniaAha1-dependent proliferation
Bartsch K, Hombach-Barrigah A and Clos J.
Cell Stress and Chaperones, accepted
Methoxylated 2'-hydroxychalcones as antiparasitic hit compounds.
Borsari C, Santarem N, Torrado J, Olías AI, Corral MJ, Baptista C, Gul S, Wolf M, Kuzikov M, Ellinger B, Reinshagen J, Linciano P, Tait A, Costantino L, Freitas-Junior LH, Moraes CB, Pascoalino B, Alcântara LMaria, Franco CH, Bertolacini CD, Fontana V, Tejera Nevado P, Clos J, Alunda JM, Cordeiro-da-Silva A, Ferrari S, Costi MP
European Journal of Medicinal Chemistry, 126, 1129-1135
Leishmania donovani chaperonin 10 regulates parasite internalization and intracellular survival in human macrophages
Colineau L, Clos J, Moon KM, Foster LJ and Reiner NE
Med Microbiol Immunol 206, 235-257.
Characterization of the protein tyrosine phosphatase LmPRL-1 secreted by Leishmania major via the exosome pathway.
Leitherer S, Clos J, Liebler-Tenorio EM, Schleicher U, Bogdan C and Soulat D
Infect Immun - accepted
Leishmania Heat Shock Proteins as Effectors of Immune Evasion and Virulence
Bartsch K, Eick J, Zirpel H and Clos J
Current Immunology Reviews, 2017, 13 - accepted
MAPK1 of Leishmania donovani interacts and phosphorylates HSP70 and HSP90 subunits of foldosome complex
Kaur, P., Garg, M., Hombach-Barrigah, A., Clos, J., and Goyal, N
Sci Rep 7, 10202
Synthetic analogs of an Entamoeba histolytica glycolipid designed to combat intracellular Leishmania infection
Choy, S.L., Bernin, H., Aiba, T., Bifeld, E., Lender, S.C., Muhlenpfordt, M., Noll, J., Eick, J., Marggraff, C., Niss, H., N.G. Roldan, S. Tanaka, M. Kitamura, K. Fukase, J. Clos, E. Tannich, Y. Fujimoto & H. Lotter
Sci Rep 7, 9472
A versatile qPCR assay to quantify trypanosomatidic infections of host cells and tissues.
Bifeld E, Tejera Nevado P, Bartsch J, Eick J, Clos J.
Med Microbiol Immunol. doi 10.1007/s00430-016-0460-3
Profiling of flavonol derivatives for the development of anti-trypanosomatidic drugs.
Borsari C, Luciani R, Pozzi C, Pohner I, Henrich S, Trande M, Cordeiro-da-Silva A, Santarem N, Baptista C, Tait A, Di Pisa F, Dello Iacono L, Landi G, Gul S, Wolf M, Kuzikov M, Ellinger B, Reinshagen J, Witt G, Gribbon P, Kohler M, Keminer O, Behrens B, Costantino L, Tejera Nevado P, Bifeld E, Eick J, Clos J, Torrado J, Jimenez-Anton MD, Corral MJ, Alunda JM, Pellati F, Wade RC, Ferrari S, Mangani S, Costi MP
J Med Chem. doi: 10.1021/acs.jmedchem.6b00698
Joining forces: first application of a rapamycin-induced dimerizable Cre system for conditional null mutant analysis in Leishmania.
Späth GF, Clos J
Mol Microbiol doi: 100:923-927.10.1111/mmi.13374
A Telomeric Cluster of Antimony Resistance Genes on Chromosome 34 of Leishmania infantum
Tejera Nevado P, Bifeld E, Höhn K, Clos J.
Antimicrob Agents Chemother. doi: 10.1128/AAC.00544-16
Phenotypic Characterization of a Leishmania donovani Cyclophyilin 40 Null Mutant.
Wai-Lok Y, Lambertz U, Colineau L, Pescher P, MacDonald A, Zander D, Retzlaff S, Eick J, Reiner NE, Clos J, Späth GF.
J Eukaryot Microbiol. doi: 10.1111/jeu.12329
Geographical sequence variation in the Leishmania major virulence factor P46
Eugenia Bifeld, Mareike Chrobak, Dorothea Zander, Ulrike Schleicher, Gabriele Schönian, Joachim Clos
Infection, Genetics and Evolution 30 (2015) 195–205
Heat Shock Proteins of Leishmania: Parasites in the Driver's Seat
Joachim Clos and Antje Hombach
Adak, S., Datta, R. (Eds.), Leishmania – Current Biology and Control. Caister Academic Press, Norfolk, United Kingdom, pp. 17-36.
Leishmania donovani P23 protects parasites against HSP90 inhibitor-mediated growth arrest
Hombach A, Ommen G, Sattler V, Clos J
Cell Stress & Chaperones 2015, 20, 673-685
The genetics of Leishmania virulence
Bifeld, E. and Clos, J.
Med Microbiol Immunol, 204, 619-634
Co-circulation of a novel phlebovirus and Massilia virus in sandflies, Portugal
Amaro, Fatima, Ze-Ze, Libia, Alves, Maria J., Borstler, Jessica, Clos, Joachim, Lorenzen, Stephan, Becker, Stefanie Christine, Schmidt-Chanasit, Jonas, and Cadar, Daniel
Virology journal 12, 174
A Novel Marker, ARM58, Confers Antimony Resistance to Leishmania spp
Nühs A, Schäfer C, Zander D, Trübe L, Tejera Nevado P, Schmidt S, Arevalo J, Adaui V, Maes L, Dujardin J-C, Clos J
Int. J. Parasitol: Drugs and Drug Resistance (2014) 4:37-47
ARM58 Overexpression Reduces Intracellular Antimony Concentration in Leishmania infantum
Schäfer C, Tejera Nevado P, Zander D, Clos J
Antimicrob Agents Chemother (2014) 58:1565–1574
No stress - Hsp90 and the signal transduction in Leishmania
Hombach A, Clos J
Parasitology (2014) 141, 1156–1166
Cyclophilin 40-deficient Leishmania donovani fail to undergo stress-induced development of the infectious metacyclic stage
Yau W-L, Pescher P, Macdonald A, Zander D, Retzlaff S, Blisnick T, Rotureau B, Bastin P, Clos J, Späth G
Cell. Microbiol. (2014) 93:80-97
Leishmania infantum EndoG is an endo/exo-nuclease essential for parasite survival
Rico E, Oliva C, Gutierrez KJ, Alzate JF, Genes CM, Moreno D, Casanova E, Gigante A, Perez-Perez MJ, Camarasa MJ, Clos J, Gago F, Jimenez-Ruiz A
PloS one (2014) 9:e89526
A small heat shock protein is essential for thermotolerance and intracellular survival of Leishmania donovani
Hombach A, Ommen G, MacDonald A, Clos J
J. Cell Science (2014) in press
The Hsp90-Sti1 Interaction is Critical for Leishmania donovani Proliferation in Both Life Cycle Stages
Hombach A, Ommen G, Chrobak M, Clos J
Cell Microbiol (2013) 15:585-600
The loss of virulence of histone H1 overexpressing Leishmania donovani parasites is directly associated with a reduction of HSP83 rate of translation
Alexandratos A, Clos J, Samiotaki M, Efstathiou A, Panayotou G, Soteriadou K, Smirlis D
Mol Microbiol (2013) 88:1015-1031
Leishmania donovani HslV does not interact stably with HslU proteins
Chrobak M, Forster S, Meisel S, Pfefferkorn R, Forster F, Clos J
Int J Parasitol (2012) 42:329-339
Secreted virulence factors and immune evasion in visceral leishmaniasis
Lambertz U, Silverman JM, Nandan D, McMaster WR, Clos J, Foster LJ, Reiner NE
Journal of Leukocyte Biology (2012) 91:887-899
Rapid identification of Leishmania spp. in formalin-fixed, paraffin-embedded tissue samples by fluorescence in situ hybridization
Frickmann H, Alnamar Y, Essig A, Clos J, Racz P, Barth TF, Hagen RM, Fischer M, Poppert S
TM & IH (2012) 17:1117-1126
Overexpression of a single Leishmania major gene is sufficient to enhance parasite infectivity in vivo and in vitro
Reiling L, Chrobak M, Schmetz C, Clos J
Mol Microbiol (2010) 76:1175-1190
Phosphoproteome dynamics reveals heat shock protein complexes specific to the Leishmania infectious stage
Morales M, Watanabe R, Dacher M, Chafey P, Osorio y Fortéa J, Beverley S, Ommen G, Clos J, Hem S, Lenormand P, Rousselle J-C, Namane A, Spath G
Proc Natl Acad Sci U S A (2010) 107:8381-8386
The co-chaperone SGT of Leishmania donovani is essential for the parasite's viability
Ommen G, Chrobak M, Clos J
Cell Stress and Chaperones (2010) 39:541-546
An exosome-based secretion pathway is responsible for protein export from Leishmania and communication with macrophages
Silverman JM, Clos J, de'Oliveira CC, Shirvani O, Fang Y, Wang C, Foster LJ, Reiner NE
J Cell Sci (2010) 123:842-852
Leishmania exosomes modulate innate and adaptive immune responses through effects on monocytes and dendritic cells
Silverman JM, Clos J, Horakova E, Wang AY, Wiesgigl M, Kelly I, Lynn MA, McMaster WR, Foster LJ, Levings MK, Reiner NE
J Immunol (2010) 185:5011-5022
LmxMPK4, an essential mitogen-activated protein kinase of Leishmania mexicana is phosphorylated and activated by the STE7-like protein kinase LmxMKK5
von Freyend SJ, Rosenqvist H, Fink A, Melzer IM, Clos J, Jensen ON, Wiese M
Int J Parasitol (2010) 40:969-978
Characterization of a Subunit of the Outer Dynein Arm Docking Complex Necessary for Correct Flagellar Assembly in Leishmania donovani
Harder S, Thiel M, Clos J, Bruchhaus I
PLoS Negl Trop Dis (2010) 4:e586
One-step generation of double-allele gene replacement mutants in Leishmania donovani
Ommen G, Lorenz S, Clos J
Int J Parasitol (2009) 39:541-546
Leishmania infantum expresses a mitochondrial nuclease homologous to EndoG that migrates to the nucleus in response to an apoptotic stimulus
Rico E, Alzate JF, Arias AA, Moreno D, Clos J, Gago F, Moreno I, Dominguez M, Jimenez-Ruiz A
Mol Biochem Parasitol (2009) 163:28-38
Identification of a Leishmania infantum gene mediating resistance to miltefosine and SbIII
Choudhury K, Zander D, Kube M, Reinhardt R, Clos J
Int J Parasitol (2008) 38:1411-1423
Leishmania major: identification of developmentally regulated proteins in procyclic and metacyclic promastigotes
Mojtahedi Z, Clos J, Kamali-Sarvestani E
Exp Parasitol (2008) 119:422-429
Structural characterization of beta-sheeted oligomers formed on the pathway of oxidative prion protein aggregation in vitro
Redecke L, von Bergen M, Clos J, Konarev PV, Svergun DI, Fittschen UE, Broekaert JA, Bruns O, Georgieva D, Mandelkow E, Genov N, Betzel C
J Struct Biol (2007) 157:308-320
Spontaneous recovery of pathogenicity by Leishmania major hsp100-/- alters the immune response in mice
Reiling L, Jacobs T, Kroemer M, Gaworski I, Graefe S, Clos J
Infect Immun (2006) 74:6027-6036
Functional cloning as a means to identify Leishmania genes involved in drug resistance
Clos J, Choudhury K
Mini Rev Med Chem (2006) 6:123-129
Complement C3 is required for the progression of cutaneous lesions and neutrophil attraction in Leishmania major infection
Jacobs T, Andra J, Gaworski I, Graefe S, Mellenthin K, Kromer M, Halter R, Borlak J, Clos J
Med Microbiol Immunol (2005) 194:143-149
Comparative analysis of the human and chicken prion protein copper binding regions at pH 6.5
Redecke L, Meyer-Klaucke W, Koker M, Clos J, Georgieva D, Genov N, Echner H, Kalbacher H, Perbandt M, Bredehorst R, Voelter W, Betzel C
J Biol Chem (2005) 280:13987-13992
Stage-specific expression of the mitochondrial co-chaperonin of Leishmania donovani, CPN10
Zamora-Veyl FB, Kroemer M, Zander D, Clos J
Kinetoplastid Biol Dis (2005) 4:3
Oligomerization of the proteolytic products is an intrinsic property of prion proteins
Georgieva D, Koker M, Redecke L, Perbandt M, Clos J, Bredehorst R, Genov N, Betzel C
Biochem Biophys Res Commun (2004) 323:1278-1286
Synthetic human prion protein octapeptide repeat binds to the proteinase K active site
Georgieva D, Rypniewski W, Echner H, Perbandt M, Koker M, Clos J, Redecke L, Bredehorst R, Voelter W, Genov N, Betzel C
Biochem Biophys Res Commun (2004) 325:1406-1411
A Leishmania donovani gene that confers accelerated recovery from stationary phase growth arrest
Hoyer C, Zander D, Fleischer S, Schilhabel M, Kroener M, Platzer M, Clos J
Int J Parasitol (2004) 34:803-811
Developmentally induced changes of the proteome in the protozoan parasite Leishmania donovani
Bente M, Harder S, Wiesgigl M, Heukeshoven J, Gelhaus C, Krause E, Clos J, Bruchhaus I
Proteomics (2003) 3:1811-1829
Comparison of the A2 gene locus in Leishmania donovani and Leishmania major and its control over cutaneous infection
Zhang WW, Mendez S, Ghosh A, Myler P, Ivens A, Clos J, Sacks DL, Matlashewski G
J Biol Chem (2003) 278:35508-35515
Inhibition of HSP90 in Trypanosoma cruzi Induces a Stress Response but No Stage Differentiation
Graefe SE, Wiesgigl M, Gaworski I, Macdonald A, Clos J
Eukaryot Cell (2002) 1:936-943
Heat Shock Protein 90 Homeostasis Controls Stage Differentiation in Leishmania donovani.
Wiesgigl M, Clos J
Mol Biol Cell (2001) 12:3307-3316.
Leishmania and the Leishmaniases: the heat shock protein 90 of Leishmania donovani.
Wiesgigl M, Clos J
Med. Microbiol. Immunol. (2001) 190:27-31
Leishmania and the Leishmaniases: Use of genetic complementation to identify gene(s) which specify species-specific organ tropism of Leishmania.
Hoyer C, Mellenthin K, Schilhabel M, Platzer M, Clos J
Med. Microbiol. Immunol. (2001) 190:53-56
Expression and Subcellular Localization of Cpn60 Protein Family Members in Leishmania donovani
Schlueter, A., M. Wiesgigl, C. Hoyer, S. Fleischer, L. Klaholz, C. Schmetz & J. Clos
Biochim. Biophys. Acta 2000 1491: 65-74
Cross-species Homologous Recombination in Leishmania donovani Reveals the Sites of Integration
Krobitsch, S. and J. Clos
Mol. Biochem. Parasitol. 2000 107: 123-128
Uniform distribution of transcription complexes on the clpB gene locus of Leishmania donovani
Wiesgigl, M. & J. Clos
Protist 1999 150: 369-373
A novel role for 100 kD heat shock proteins in the parasiteLeishmania donovani
Krobitsch, S., and Clos, J.
Cell Stress Chaperones 1999 4, 191-198
Leishmania donovani heat shock protein 100: characterization and function in amastigote stage differentiation
Krobitsch, S., Brandau, S., Hoyer, C., Schmetz, C., Hübel, A., and Clos, J.
J Biol Chem 1998 273, 6488-6494
Chemical stress does not induce heat shock protein synthesis in Leishmania donovani
Clos, J., S. Brandau & C. and Hoyer, C
Protist 1998 149: 167-172
Leishmania major Hsp100 is required chiefly in the mammalian stage of the parasite
Hubel, A., Krobitsch, S., Horauf, A., and Clos, J.
Mol Cell Biol 1997 17, 5987-5995
Transcription of the Leishmania major Hsp70-I gene locus does not proceed through the noncoding region
Dresel, A. & J. Clos
Exp Parasitol 1997 86: 206-212
The genomic organization of the HSP83 gene locus is conserved in three Leishmania species
Hubel, A. & J. Clos
Exp Parasitol 1996 82: 225-228
A member of the ClpB family of stress proteins is expressed during heat shock in Leishmania spp
Hubel, A., Brandau, S., Dresel, A., and Clos, J.
Mol Biochem Parasitol 1995 70, 107-118
High constitutive levels of heat-shock proteins in human-pathogenic parasites of the genus Leishmania
Brandau, S., Dresel, A., and Clos, J. (). .
Biochem J 1995 310, 225-232
pJC20 and pJC40- two high-copy-number vectors for T7 RNA polymerase-dependent expression of recombinant genes in Escherichia coli
Clos, J. & S. Brandau
Prot. Expression Purif. 1994 5: 133-137