Dr GM Preston
Molecular Plant-Microbe Interactions
The biology and evolution of plant-associated Pseudomonas
Bacteria belonging to the genus Pseudomonas
cause diseases of a wide variety of plants, including economically important crop plants such as tomato, wheat and bean, and are commonly used as model organisms to understand the molecular basis of plant disease. Our research aims to understand the evolution of plant pathogenic (disease causing) lifestyles in Pseudomonas
and the molecular mechanisms used by plant pathogenic and non-pathogenic Pseudomonas
to colonise plant tissues.
Our projects draw on the wealth of genome sequence information that is available for Pseudomonas
, and we use a wide range of experimental techniques ranging from microbiology and microscopy to molecular genetics and metabolomics.
I) Pseudomonas as agents of plant disease
Plant pathogenic Pseudomonas
such as Pseudomonas syringae
are able to multiply in the apoplastic fluid that surrounds plant cells, and use toxins, hormones and secreted proteins to suppress plant defences and maintain access to plant nutrients. We are using genomic, molecular genetic and metabolomic techniques to investigate how the molecular composition of apoplastic fluid affects the growth of P. syringae
and how P. syringae
and other pseudomonads are adapted for growth in plant tissues. We are particularly interested in understanding how successful plant pathogens, such as P. syringae
, manipulate plant metabolism to create a favourable environment for pathogen growth, and in understanding the role of environmental factors, such as soil nutrients, in modifying plant metabolism and disease susceptibility.
We collaborate with researchers in the Plant Science and Chemistry departments at Oxford, Rothamsted Research (Prof. Mike Beale and Dr. Jane Ward), UWE (Dr. Dawn Arnold), University of Reading (Dr. Robert Jackson), Kingston University (Dr. Ali Ryan and Dr. Edith Sim) and the University of Sheffield (Dr. Wei Huang) to investigate how factors such as nitrogen, cyanide, toxic metals and plant-derived anti-microbial compounds affect susceptibility and disease resistance in plants, and to develop techniques that can be used to monitor cellular processes and plant defences. We have also collaborated with Prof. Jotun Hein (Statistics) to develop in silico
models of the structure and evolution of metabolic networks in Pseudomonas,
which has led to the development of a software tool for studying and comparing metabolic pathways.
II) The role of "plant pathogenicity" factors in mushroom pathogenic Pseudomonas and plant growth-promoting Pseudomonas
A second research theme in the group is founded on the observation that some of the “pathogenicity” mechanisms that have been characterised in plant pathogenic bacteria are also present in mushroom pathogenic and plant growth promoting Pseudomonas,
which raises important questions about the evolution of these mechanisms and their role in Pseudomonas-
plant interactions. For example, both plant pathogenic and plant growth promoting Pseudomonas
possess similar mechanisms to inject proteins into host cells. We are currently investigating whether these mechanisms are involved in plant colonisation, or whether they have alternative uses in bacterial interactions with plant-associated eukaryotes such as fungi, nematodes and amoebae. Research into Pseudomonas
interactions with nematodes and fungi has uncovered novel mechanisms for inhibition of nematode predation and fungal growth, which we are studying in collaboration with Prof. J. Hodgkin (Dept. of Biochemistry, University of Oxford), Dr. David Studholme (University of Exeter), Dr. J. Leveau (UC-Davis), Dr. Pascale Frey-Klett (INRA-Nancy), Dr. David Guttman (University of Toronto).
Dr. Preston is the Programme Director of the BBSRC-funded Interdisciplinary Bioscience DTP. Prospective graduate students may wish to consider applying for graduate study in the Department of Plant Sciences or to the Interdisciplinary Bioscience Doctoral Training Partnership, Life Science Interface Doctoral Training Centre or the Systems Biology Doctoral Training Centre. For further details please visit www.dtc.ox.ac.uk
Preston Group Members
2013) Pseudomonas fluorescens NZI7 repels grazing by C. elegans, a natural predator ISME Journal..
2012) Oxygenase-catalyzed ribosome hydroxylation occurs in prokaryotes and humans Nature Chemical Biology..
2011) Pseudomonas fluorescens BBc6R8 type III secretion mutants no longer promote ectomycorrhizal symbiosis Environmental Microbiology Reports. 3 (2): pp 203-210.
2011) Local biotic environment shapes the spatial scale of bacteriophage adaptation to bacteria American Naturalist. 177 (4): pp 440-451.
2011) Comparative analysis of metabolic networks provides insight into the evolution of plant pathogenic and nonpathogenic lifestyles in Pseudomonas Molecular Biology and Evolution. 28 (1): pp 483-499.
2011) The metabolic interface between Pseudomonas syringae and plant cells Current Opinion in Microbiology. 14 (1): pp 31-38.
2010) A Bayesian approach to the evolution of metabolic networks on a phylogeny PLoS Computational Biology 6(8): e1000868..
2010) Mutations in Î³-aminobutyric acid (GABA) transaminase genes in plants or Pseudomonas syringae reduce bacterial virulence Plant Journal. 64 (2): pp 318-330.
2010) How bacterial plant pathogens escape their fate in disease-resistant plants Microbiology Today. 37 (3): pp 164-169
2010) Karma chameleons: How bacterial plant pathogens escape their fate in disease resistant plants Microbiology Today (www.sgm.ac.uk/pubs/micro_today : Aug2010). pp 164-169
2010) Agroinfiltration reduces ABA levels and suppresses Pseudomonas syringae-elicited salicylic acid production in Nicotiana tabacum. PloS one. 5 (1):.
2010) Agroinfiltration reduces ABA Levels and suppresses Pseudomonas syringae-elicited salicylic acid production in Nicotiana tabacum PLoS ONE. 5 (1): pp 1-12.
2009) Pseudomonas syringae pv. syringae B728a hydrolyses indole-3-acetonitrile to the plant hormone indole-3-acetic acid Molecular Plant Pathology. 10 (6): pp 857-865.
2009) Rahnuma: Hypergraph-based tool for metabolic pathway prediction and network comparison Bioinformatics. 25 (14): pp 1831-1832.
2009) A stochastic model for the evolution of metabolic networks with neighbor dependence Bioinformatics. 25 (12): pp 1528-1535.
2009) Genomic and genetic analyses of diversity and plant interactions of Pseudomonas fluorescens Genome Biology. 10 (5):.
2008) Pseudomonas syringae pv. tomato DC3000 uses constitutive and apoplast-induced nutrient assimilation pathways to catabolize nutrients that are abundant in the tomato apoplast Molecular Plant-Microbe Interactions. 21 (2): pp 269-282.
2008) Adaptation to the plant apoplast by plant pathogenic bacteria Plant Pathogenic Bacteria: Genomics and Molecular Biology. Eds. R. W. Jackson. Horizon Scientific Press, Norwich, UK. ISBN: 9781904455370.
2007) Integrated bioinformatic and phenotypic analysis of RpoN-dependent traits in the plant growth-promoting bacterium Pseudomonas fluorescens SBW25 Environmental Microbiology. 9 (12): pp 3046-3046.
2007) Bacterial Pathogenomics . ASM Press. ISBN: 1555814514.
2007) Post-genomic analysis of plant pathogenic bacteria Bacterial Pathogenomics. Eds. M. J. Pallen, K. Nelson, and G. M. Preston. ASM Press. ISBN: 1555814514. pp 392-418
2007) Ultrasound-mediated DNA transfer for bacteria Nucleic Acids Research. 35 (19):.
2006) Quantitative in situ assay of salicylic acid in tobacco leaves using a genetically modified biosensor strain of Acinetobacter sp. ADP1 Plant Journal. 46 (6): pp 1073-1083.
2005) Genetic characterization of Pseudomonas fluorescens SBW25 rsp gene expression in the phytosphere and in vitro Journal of Bacteriology. 187 (24): pp 8477-8488.
2005) Protein domains and architectural innovation in plant-associated proteobacteria BMC Genomics. 6:.
2004) Eukaryotic and prokaryotic stomatins: The proteolytic link Blood Cells, Molecules, and Diseases. 32 (3): pp 411-422.
2004) The type III secretion systems of plant-associated pseudomonads: Genes and proteins on the move Pseudomonas. Eds. J. L. Ramos. Plenum Press. ISBN: 0306483769. pp 181-219
2004) Plant perceptions of plant growth-promoting Pseudomonas Philosophical Transactions of the Royal Society of London Series B Biological Sciences. 359 (1446): pp 907-918
2003) Genes encoding a cellulosic polymer contribute toward the ecological success of Pseudomonas fluorescens SBW25 on plant surfaces Molecular Ecology. 12 (11): pp 3109-3121
2000) Regulatory interactions between the Hrp type III protein secretion system and coronatine biosynthesis in Pseudomonas syringae pv. tomato DC3000 Microbiology. 146 (10): pp 2447-2456
2000) Pseudomonas syringae pv. tomato: the right pathogen, of the right plant, at the right time Molecular Plant Pathology. 1 (5): pp 263-275.
2000) In vivo expression technology strategies: Valuable tools for biotechnology Current Opinion in Biotechnology. 11 (5): pp 440-444.
1998) The Pseudomonas syringae pv. tomato HrpW protein has domains similar to harpins and pectate lyases and can elicit the plant hypersensitive response and bind to pectate Journal of Bacteriology. 180 (19): pp 5211-5217
1998) Characterization of the hrpC and hrpRS operons of Pseudomonas syringae pathovars syringae, tomato, and glycinea and analysis of the ability of hrpF, hrpG, hrcC, hrpT, and hrpV mutants to elicit the hypersensitive response and disease in plants Journal of Bacteriology. 180 (17): pp 4523-4531
1998) Negative regulation of hrp genes in Pseudomonas syringae by hrpV Journal of Bacteriology. 180 (17): pp 4532-4537
1998) Bacterial genomics and adaptation to life on plants: Implications for the evolution of pathogenicity and symbiosis Current Opinion in Microbiology. 1 (5): pp 589-597
Our research is funded by the Biotechnology and Biological Sciences Research Council (BBSRC), the Leverhulme Trust and the John Fell Fund.
Current job opportunities
Applications are currently being accepted for October 2013 commencement with the MPLS Doctoral Training Centre’s three programmes: Life Sciences Interface Doctoral Training Centre; Systems Biology Doctoral Training Centre; and Systems Approaches to Biomedical Science Industrial Doctorate Centre. To find out more information about the programmes held at the Doctoral Training Centre please visit: http://www.dtc.ox.ac.uk/
David Studholme, University of Exeter, UK
Dawn Arnold, University of the West of England, UK
Jane Ward and Mike Beale, Rothamsted Research, UK
Robert Jackson, University of Reading, UK
Wei Huang, University of Sheffield, UK
Alan Collmer, Cornell University, Ithaca, NY, USA
Carol Bender, Oklahoma State University, Stillwater, OK, USA
Johan Leveau, UC-Davis, Davis, CA, USA
Pascale Frey-Klett, INRA-Nancy, France
David Guttman, University of Toronto
Joyce Loper, USDA, Oregon State University