Prof Graham Stewart
Tuberculosis (TB) is one of the most important infectious diseases of mankind, claiming 30,000 lives every week. One third of the world's population carry an asymptomatic persistent infection with a 10% risk of progression to active disease. Of the 9 million new cases of tuberculosis every year, more than half a million are caused by strains of Mycobacterium tuberculosis that have acquired multidrug-resistance. BCG is currently the only vaccine used against TB and while it is successful in protecting against disease in children, it is ineffective against adult pulmonary TB. Improvement in diagnosis, drugs and vaccines for tuberculosis will be needed to control this epidemic.
Bovine tuberculosis is the most important veterinary health problem in the UK. The projected economic burden to the UK over the next decade is predicted to be £1 billion. Control is likely to require an integrated approach with vaccination of cattle representing a key component. Presently, the M.bovis BCG vaccine represents the most encouraging vaccination option, but it compromises the diagnostic skin test and has a protective efficacy of only ~50-70%.
To form a rational platform upon which to develop novel drugs, vaccines and diagnostic agents we are working to understand the molecular basis of how M. tuberculosis and M.bovis are able to establish infection and generate disease.
High-throughput functional genomic studies of M.tuberculosis complex bacteria and their host cells by our lab and others have revealed that virulence is controlled by complex multifactorial interactions between thousands of bacterial and host components. From these interaction networks emerge the properties that characterise the pathogenesis of TB. Systems Biology provides a strategy to explore this complexity, integrating experimental analysis and computational tools to develop predictive models that will facilitate effective drug and vaccine development strategies based on a higher level of biological understanding.
We are identifying and studying molecular interaction networks associated with the pathogenesis features below:
Mycobacterial inhibition of phagosome maturation
The success of M.tuberculosis/M.bovis as pathogens relies on an ability to grow inside host macrophages. Multiple factors are involved in intracellular survival but a key feature is the ability of M. tuberculosis to arrest the normal process of phagosome maturation, blocking acidification of the intracellular compartment and fusion with lysosomes.
Mycobacterial control of host cell death
Evidence suggests that M.tuberculosis is able to control the fate of host cells such as macrophages,neutrophils and dendritic cells. Early in infection it is able to inhibit apoptosis to preserve its replicative niche but later it has the capacity to induce an inflammatory form of cell death.
Mycobacterial metabolism in host cells/tissues
The features of mycobacterial metabolism during infection are poorly understood. The bacterium exists in many and diverse sites in the host and understanding the variety and nature of metabolic processes utilised in these environments will be essential to novel drug discovery.
The mycobacterial stress response
Pathogenic mycobacteria must endure a variety of other hostile environments during infection. The bacteria counter these harsh conditions with specific and general stress responses that remodel the physiology, biochemistry and structure of the cell. These mechanisms are an essential component of pathogenicity.
In collaboration with Professor Mike Taylor we aim to understand the evolution and macroecology of leprosy and tuberculosis by studying ancient pathogen DNA in archaeological specimens. Characterisation of individual polymorphisms or even reconstruction of whole genome sequences is possible for mycobacterial infections from over 1000 years ago, allowing accurate phylogenetic and evolutionary models to be developed.
Financial support for our research is provided by The Wellcome Trust, the BBSRC and the Rosetrees Trust.
Main internal collaborators:
BMS1026 Microbiology: An Introduction to the Microbial World
BMS1031 Introduction to Molecular Biology and Genetics
BMS2037 Cellular Microbiology and Virology
BMS3079 Human Microbial Diseases
MSc Medical Microbiology
MMIM018 Microbial Genetics and Molecular Biology
MMIM026 Research Methods 1
MMIM024 Pathogenesis of infectious disease
Infectious Diseases Research Group Leader
Chair Board of Examinations MSc Medical Microbiology Programmes
Mendum TA, Wu H, Kierzek AM and Stewart GR (2015). Lipid metabolism and Type VII secretion systems dominate the genome scale virulence profile of Mycobacterium tuberculosis in human dendritic cells. BMC Genomics 16: 372
Inskip SA, Taylor GM, Zakrzewski SR, Mays SA, Pike AWG, Llewellyn G, Williams CM, Lee O Y-C, Wu H, Minnikin DE, Besra GS and Stewart GR. (2015). Osteological, Biomolecular and Geochemical Examination of an Early Anglo-Saxon Case of Lepromatous Leprosy. PLoS One 13;10(5): e0124282
Francis R, Butler RE, Stewart GR. (2014). Mycobacterium tuberculosis ESAT-6 is a leukocidin causing Ca2+ influx, necrosis and neutrophil extracellular trap formation. Cell Death and Disease 5(10):e1474.
Mendum TA, Schuenemann VJ, Roffey S, Taylor GM, Wu H, Singh P, Tucker K, Hinds J, Cole ST, Kierzek AM, Nieselt K, Krause J, and Stewart GR. (2014) Mycobacterium leprae genomes from a British medieval leprosy hospital: towards understanding an ancient epidemic. BMC Genomics 15:270.
Schuenemann VJ, Singh P, Mendum T, Krause-Kyora B, Jäger G, Bos KI, Herbig A, Economou C, Benjak A, Busso P, Nebel A, Boldsen JL, Kjellström A, Stewart GR, Taylor GM, Bauer P, Lee OY-C, Minnikin DE, Tucker K, Roffey S, Sow SO, Cole ST, Nieselt K, and Krause J. (2013). Genome-wide comparison of medieval and modern Mycobacterium leprae. Science 12;341(6142):179-83.
Taylor GM, Tucker K, Butler R, Pike AWG, Lewis J, Roffey S, Marter, Lee OY-C, Wu HHT, Minnikin DE, Besra GS, Singh P, Cole ST, Stewart GR. (2013) Detection and Strain Typing of Ancient Mycobacterium leprae from a Medieval Leprosy Hospital. PLoS ONE 8(4): e62406.
Butler RE, Brodin P, Jang J, Jang MS, Robertson BD, Gicquel B and Stewart GR. (2012) The balance of apoptotic and necrotic cell death in Mycobacterium tuberculosis infected macrophages is not dependent on bacterial virulence. PLoS ONE 7(10):e47573
Snelgrove RJ, Cornere MM, Edwards L, Dagg B, Keeble J, Rodgers A, Lyonga DE, Stewart GR, Young DB, Walker B, Hussell T. (2012). OX40 ligand fusion protein delivered simultaneously with the BCG vaccine provides superior protection against murine Mycobacterium tuberculosis infection. Journal of Infectious Diseases 205:975-983.
Brodin P, Poquet Y, Levillain F, Peguillet I, Larrouy-Maumus G, Gilleron M, Christophe T, Fenistein D, Ewann F, Jang J, Jang M-S, Rauzier J, Carralot J-P, Shrimpton R, Genovesio A, Asensio JAG, Puzo G, Martin C, Brosch R, Stewart GR, Gicquel B and Neyrolles O. (2010) High content phenotypic cell-based visual screen identifies Mycobacterium tuberculosis acyltrehalose-containing glycolipids involved in phagosome remodelling. PLoS Pathogens 6(9): e1001100
Estorninho M, Smith H, Thole J, Harders-Westerveen J, Kierzek A, Butler RE, Neyrolles O and Stewart GR. (2010) ClgR regulation of chaperone and protease systems is essential for Mycobacterium tuberculosis parasitism of the macrophage. Microbiology 156, part 11, pp. 3445 - 3455.
Butler RE, Cihlarova V and Stewart GR. (2010) Effective generation of reactive oxygen species in the mycobacterial phagosome requires K+ efflux from the bacterium. Cellular Microbiology 12(8),1186-93.
Beste D, Espasa M, B. Bonde, C. Kierzek AM, Stewart GR and McFadden J. (2009) The genetic requirements for fast and slow growth in mycobacteria. PloS ONE 4, E5349
Wilkinson KA, Newton SM, Stewart GR, Martineau AR, Sullivan SM, Herrmann J-L, Neyrolles O, Young DB, Wilkinson RJ (2009) Genetic determination of the effect of post-translational modification on the innate immune response to the 19kDa lipoprotein of Mycobacterium tuberculosis. BMC Microbiology 9:93..
Henao-Tamayo M, Junqueira-Kipnis AP, Ordway D, Gonzales-Juarrero M, Stewart GR, Young DB, Wilkinson RJ, Basaraba RJ, Orme IM. (2007) A mutant of Mycobacterium tuberculosis lacking the 19-kDa lipoprotein Rv3763 is highly attenuated in vivo but retains potent vaccinogenic properties. Vaccine 25(41):7153-9.
Beste D, Hooper T, Stewart GR, Bonde B, Avignone-Rossa C, Bushell M, Wheeler PR, Klamt S, Kierzek AM, and McFadden JJ. (2007) GSMN-TB: a web-based genome scale network model of Mycobacterium tuberculosis metabolism. Genome Biology. 8(5):R89.
Newton SM, Smith RJ, Wilkinson KA, Garton NJ, Staples KJ, Ziegler-Heitbrock L, Stewart GR, Wain JR, Nicol MP, Martineau AR, Al-Obaidi A, Shafi J, Levin M, Rajakumar K, Andrew PW, Barer MR, Wilkinson RJ. (2006). A deletion defining a common Asian lineage of Mycobacterium tuberculosis associates with immune subversion. Proceedings of the National Academy of Science 103, 15594-98.
Humphreys I.R., Stewart G.R., Turner D.J., Patel J., Karamanou D., Snelgrove R.J., Young D.B. (2006). A role for dendritic cells in the dissemination of mycobacterial infection. Microbes and Infection. 8(5),1339-46.
Pitarque S., Herrmann J-L., Duteyrat J-L, Jackson M., Stewart G.R., Lecointe F., Payré B., Schwartz O., Young D.B., Marchal G., Lagrange P.H., Puzo G., Gicquel B., Nigou J. and Neyrolles O. (2005) Deciphering the molecular bases of Mycobacterium tuberculosis binding to DC-SIGN reveals an underestimated complexity. Biochemical Journal 392, 615-24.
Stewart G.R., Patel J., Robertson B.D., Rae A. and Young D.B. (2005). Mycobacterial mutants with defective control of phagosomal acidification. PLoS Pathogens 1, 269-78.
Stewart G.R., Wilkinson K.A., Wain J.R., Sullivan S.M., Newton S.M., Patel J., Neyrolles O., Pool K.L., Young D.B. and Wilkinson R.J. (2005) The effects of deletion or overexpression of the 19 kDa lipoprotein (Rv3763) on the innate response to Mycobacterium tuberculosis. Infection and Immunity 73(10), 6831-7.
Murphy H.N., Stewart G.R., Mischenko V., Apt A., Harris R., McAlister M.S.B., Driscoll P.C., Young D.B., and Robertson B.D. (2005) The OtsAB pathway is essential for trehalose biosynthesis in Mycobacterium tuberculosis. Journal of Biological Chemistry 280(15), 14524-9.
Wilkinson K.A., Stewart G.R., Newton S.M., Vordermeier H.M., Wain J.R., Murphy H.N., Horner K., Young D.B. and Wilkinson R.J. (2005) Infection biology of a novel alpha-crystallin of Mycobacterium tuberculosis: Acr2. Journal of Immunology 174(7), 4237-43.
Blokpoel M.C.J., Murphy H.N., O'Toole R., Wiles S., Stewart G.R., Young D.B. and Robertson B.D. (2005) Tetracycline-inducible gene regulation in mycobacteria. Nucleic Acids Research 33(2), e22 (7 pages)
Stewart G.R., Newton S., Wilkinson K.A., Murphy H.N., Robertson B.D., Wilkinson R.J. and Young D.B. (2005) The stress responsive chaperone alpha-crystallin 2 is required for pathogenesis of Mycobacterium tuberculosis. Molecular Microbiology 55(4), 1127-37.
Ciaramella A., Cavone A., Santucci M.B., Bocchino M., Galati D., Martino A., Auricchio G., Stewart G.R., Neyrolles O., Young D.B., Colizzi V. and Fraziano M. (2004) 19-kDa lipoprotein induces inflammatory apoptosis in the course of Mycobacterium tuberculosis infection. Journal of Infectious Diseases. 190, 1167-76.
Stewart G.R. and Young D.B. (2004) Heat shock proteins and the host-pathogen interaction during bacterial infection. Current Opinion in Immunology. 16, 506-10.
Stewart G.R. Robertson B.D. and Young D.B. (2004) Analysis of the function of mycobacterial DnaJ proteins by overexpression and microarray profiling. Tuberculosis 84(3-4), 180-7.
Papatheodorou I., Sergot M., Randall M, Stewart G.R. and Robertson B.D. (2004). Visualisation of microarray results to assist interpretation. Tuberculosis. 84(3-4), 275-81.
Taylor G.M., Stewart G.R, Cooke M., Ladva S. and Young D.B. (2003). Koch's Bacillus - a look at the first isolate of Mycobacterium tuberculosis from a modern perspective. Microbiology 149, 3213-3220.
Stewart G.R, Robertson B.D. and Young D.B. (2003). Tuberculosis: A problem with persistence. Nature Reviews Microbiology 1, 97-105.
Stewart G.R., Stabler R., Mangan J., Hinds J., Laing K.G., Butcher P.D. and Young D.B.. (2002). The heat shock response of Mycobacterium tuberculosis: linking gene expression, immunology and pathogenesis. Comparative and Functional Genomics 3, 348-351.
Stewart G.R. Wernisch L., Stabler R., Hinds J., Mangan J., Young D.B. and Butcher P. (2002). Dissection of the heat shock response of Mycobacterium tuberculosis using mutants and microarrays. Microbiology 148, 3129-3138.
Young D.B. and Stewart G.R. (2002). Tuberculosis Vaccines. British Medical Bulletin 62, 73-86.
Bhatt A., Stewart G.R. and Kieser T. (2002). Transposition of Tn4560 of Streptomyces fradiae in Mycobacterium smegmatis. FEMS Microbiology Letters. 206, 241-246.
Stewart G.R., Snewin V.A., O Gaora P., Tormay P., Goyal M., Brown I.B. and Young D.B. (2001). Overexpression of heat shock proteins reduces survival of Mycobacterium tuberculosis in the chronic phase of infection. Nature Medicine 7, 732-737.
Dussurget O., Stewart G., Neyrolles O., Pescher P., Young D. and Marchal G. (2001). Role of Mycobacterium tuberculosis copper-zinc superoxide dismutase. Infection and Immunity 69, 529-533.
Stewart G.R., Perry R.N. and Wright D.J. (2001). Occurrence of dopamine in Panagrellus redivivus and Meloidogyne incognita. Nematology 3, 843-858.
Yeremeev V.Y., Stewart G.R., Neyrolles N., Skrabal K., Avdienko V.G., Apt A. and Young D.B. (2000). Deletion of the 19kDa antigen does not alter the protective efficacy of BCG. Tubercle and Lung Disease 80, 243-247.
Stewart G.R., Ehrt S., Riley L., Dale J., and McFadden J. (2000). Deletion of the putative antioxidant NoxR1 does not alter the virulence of Mycobacterium tuberculosis H37Rv. Tubercle and Lung Disease 80, 237-242.
Stewart G.R., Boussinesq M., Coulson T., Elson L., Nutman T., and Bradley J.E. (1999). Onchocerciasis modulates the immune response to mycobacterial antigens. Clinical and Experimental Immunology 117, 517-523.
Bradley J.E., Stewart G.R., Atogho B., and Boussinesq M. (1998). A cocktail of recombinant Onchocerca volvulus antigens for serological diagnosis can effectively predict the endemicity of onchocerciasis infection. American Journal of Tropical Medicine and Hygiene 59, 877-82.
Stewart, G.R., Zhu, Y.H., Parredes, W., Tree, T.M., Guderian, R., and Bradley, J.E. (1997). Novel cuticular collagen Ovcol-1 of Onchocerca volvulus is preferentially recognized by immunoglobulin G3 from putatively immune individuals. Infection and Immunity 65, 164-170.
Bradley, J.E., Elson, L., Tree, T.M., Stewart, G., Guderian, R., Calvopina, M., Paredes, W., Araujo, E., and Nutman, T.B. (1995). Resistance to Onchocerca volvulus - differential cellular and humoral responses to a recombinant antigen, ovmbp20/11. Journal of Infectious Diseases 172, 831-837.
Stewart, G.R., Elson, L., Araujo, E., Guderian, R., Nutman, T.B., and Bradley, J.E. (1995). Isotype-specific characterization of antibody responses to Onchocerca volvulus in putatively immune individuals. Parasite Immunology 17, 371-380.
Stewart, G.R., Perry, R.N., and Wright, D.J. (1994). Immunocytochemical studies on the occurrence of gamma-aminobutyric acid in the nervous system of the nematodes Panagrellus redivivus, Meloidogyne incognita and Globodera rostochiensis. Fundamental And Applied Nematology 17, 433-439.
Stewart, G.R., Perry, R.N., and Wright, D.J. (1993). Studies on the amphid specific glycoprotein gp32 in different life- cycle stages of Meloidogyne species. Parasitology 107, 573-578.
Stewart, G.R., Perry, R.N., Alexander, J., and Wright, D.J. (1993). A glycoprotein specific to the amphids of Meloidogyne species. Parasitology 106, 405-412.
Stewart G.R. Papatheodorou I. and Young D.B. (2005) The stress response. In Mycobacterial Molecular Microbiology. T. Parrish (Horizon Scientific Press Ltd).
Snewin V., Stewart G. and Young D. (2000). Genetic Strategies for Vaccine Development. In Molecular Genetics of Mycobacteria. G.F. Hatfull and W.R. Jacobs, Jr. eds. (ASM Press, Washington , D.C.)
Stewart G.R. and McFadden J. (1999). Recombination. In Mycobacteria: Molecular Biology and Virulence. C. Ratledge and Dale J, eds. (Blackwell Science).