AgreenSkills session, year: 1st session, 2013
Receiving laboratory: PVBMT Plant Communities and Biological Invaders in Tropical Environment La Réunion, France
Country of origin : Spain
Functional genomic approaches to determine Ralstonia solanacearum phylotype IV host range and virulence
How do some pathogenic bacteria increase their repertoire of virulence genes and adapt to new host plants? The Ralstonia solanacearum (Rs) species complex provides unique models for studying plant-pathogen interactions, including basic biology of pathogenesis and non-host resistance in the context of an unusually broad host range and latent (asymptomatic) infection. This organism is a high-impact pathogen of economically important cash and industrial crops like tomato, potato, banana, and ornamentals. Moreover, it is spreading globally and adapting to new hosts, increasing its threat potential. Rs is a quarantine pathogen, dual use in Europe and bioterrorism select agent in the USA. The project will examine bacterial speciation and emergent properties using our collective expertise on the complex genetic diversity and evolution of Rs. Our group has developed the significant genomic resource of 26 Rs genomes – including the Blood Disease Bacterium (BDB) and R. syzygii (Rsy) a pathogen of clove – establishing a partial pangenome. However, the observed variations in pathogenicity could not be explained with comparative genomic analyses of known and likely pathogenicity determinants, or by assortment patterns of conserved hypothetical proteins. This suggests that key biological differences among strains may be explained by differential expression of genes. We therefore propose to use transcriptomic analysis to identify functions that are differentially expressed in particular hosts. What traits does a BDB strain need to solely infect banana and what is missing to be a successful tomato pathogen? We will examine and compare the pathogen RNA sets present in bananas infected with BDB during its compatible interaction, as well as the Rs RNA sets present in alternative compatible hosts like tomato. Functional genomic follow-up experiments will quantify the specific roles of identified traits in the plant-microbe interaction and will elucidate the characteristics that make this dual use quarantine organism so difficult to manage.
I completed my undergraduate degree in Plant Physiology at the University of Oviedo and my PhD at IPLA-CSIC. The purpose of my PhD thesis work was to gain molecular and physiological insights into the mechanisms of response of bifidobacteria to gastrointestinal stress factors (mainly acid pH and bile salts). This ended in the identification of protein targets and functions whose validity was further confirmed by physiological approaches. I have a postdoctoral position in the IPLA-CSIC since May 2009, and I am developing my work in the group of Probiotics and Prebiotics. I am working on the identification of extracellular proteins produced by probiotic bacteria, with relevant roles in the molecular cross-talking with the host, notably in immunomodulation. In addition, we are working on the intestinal metagenomics of specific human populations, such as Lupus patients, Allergy or premature babies.
- Borja Sánchez, Clara G. de los Reyes-Gavilán and Abelardo Margolles*. 2006. The F1F0-ATPase of Bifidobacterium animalis is involved in bile tolerance. Environmental Microbiology 8: 1825-1833.
- Borja Sánchez*, María Urdaci and Abelardo Margolles. 2010. Extracellular proteins secreted by probiotic bacteria as mediators of effects that promote mucosa-bacteria interactions. Microbiology-SGM. 156: 3232–3242.
- Francesca Turroni, Francesca Bottacini, Elena Foroni, Imke Mulder, Jae-Han Kim, Aldert Zomer, Borja Sánchez, Alessandro Bidossi, Alberto Ferrarini, Vanessa Giubellini, Massimo Delledonne, Bernard Henrissat, Pedro Coutinho, Marco Oggioni, Gerald F. Fitzgerald, David Mills, Abelardo Margolles, Denise Kelly, Douwe van Sinderen, and Marco Ventura*. 2010. Genome analysis of Bifidobacterium bifidum PRL2010 reveals metabolic pathways for host-derived glycan foraging. Proceedings of the Natural Academy of Sciences U. S. A. 107: 19514-19519.
- Borja Sánchez*, Carmen González-Tejedo, Patricia Ruas-Madiedo, María C. Urdaci, and Abelardo Margolles. 2011. Lactobacillus plantarum extracellular chitin binding protein and its role in the interaction between chitin, Caco-2 cells and mucin. Applied and Environmental Microbiology. 77: 1123-1126.
- Sánchez B*, Bernardo D, Al-Hassi HO, Mann ER, Urdaci MC, Knight SC, Margolles A. 2012. Microbiota/Host crosstalk biomarkers: regulatory response of human intestinal dendritic cells exposed to Lactobacillus extracellular encrypted peptide. PLOS ONE. 7(5): e36262.
- Francesca Turroni, Fausta Serafini, Elena Foroni, Sabrina Duranti, Mary O’Connell Motherway, Valentina Taverniti, Marta Mangifesta, Christian Milani, Alice Viappiani, Tommaso Roversi, Borja Sánchez, Andrea Santoni, Laura Gioiosa, Alberto Ferrarini, Massimo Delledonne, Abelardo Margolles, Laura Piazza, Paola Palanza, Angelo Bolchi, Simone Guglielmetti, Douwe van Sinderen, Marco Ventura. 2013. The role of sortase-dependent pili of Bifidobacterium bifidum PRL2010 in modulating bacterium-host interactions. Proceedings of the Natural Academy of Sciences U. S. A. doi: 10.1073/pnas.1303897110.
Peptide secreted by lactobacillus plantarum with immunomodulating function. WO 2013034795 A1.