E-mail: rbalbontin at igc.gulbenkian.pt
I am currently a postdoc in the Evolutionary Biology group at the IGC. After graduating in Biology at the University of Seville (2004) I did a joint-PhD between the University of Seville and the Université Paris-Sud (Paris XI), working on transcriptional and post-transcriptional regulation of gene expression in Salmonella Typhimurium (2010). My first postdoctoral fellowship was at the Centre de Génétique Moléculaire (CNRS, Gif-sur-Yvette), where I studied the regulation of iron uptake mediated by small non-coding RNAs in Salmonella Typhimurium (2010-2011). In a second postdoc stage at Harvard Medical School I studied the mutualistic interaction between Salmonella Typhimurium and Aspergillus niger and the consequences of this relationship for colonization of plants (2012-2014).
I am interested in understanding how gene expression shapes microbial evolution, and why specific regulatory mechanisms of gene expression have been selected during evolution. Complementarily, I would like to understand how epigenetics and phenotypic heterogeneity affect the “canonical” mutation-driven evolutionary processes. Moreover, I am interested in the role of microbial interaction in these processes.
Current Research Project: “Phenotypic and molecular dissection of the epistasis between antibiotic resistance mutations in Escherichia coli“, FCT fellowship (2015-2018).
The rise of bacteria resistant to multiple antibiotics is an important problem at a global scale. Mutations that confer resistance usually reduce the fitness of the bacterium so the acquisition of resistance to multiple drugs depends both on the cost of each mutation individually and on how they interact—epistasis. A recent study from our lab showed that in the absence of antibiotic the cost of multiple resistance is smaller than expected, indicating the existence of positive epistasis among alleles that confer resistance to antibiotics. I am studying the molecular mechanisms involved in the positive epistasis between resistance mutations. Since the processes involved are essential for bacterial physiology, this will also help to further understand fundamental mechanisms of cell biology.
(* first author; ** corresponding author)
Özkaya Ö, Balbontín R, Gordo I and Xavier KB (2018) Cheating on Cheaters Stabilizes Cooperation in Pseudomonas aeruginosa. Current Biology 28(13):2070-2080.e6. doi:10.1016/j.cub.2018.04.093. Press coverage
Balbontín, R.*, Villagra, N, Pardos de la Gándara, M, Mora, G, Figueroa-Bossi, N, Bossi, L (2016) Expression of IroN, the salmochelin siderophore receptor, requires mRNA activation by RyhB small RNA homologues. Molecular Microbiology.
Balbontín, R**, Vlamakis, H and Kolter, R (2014) Mutualistic interaction between Salmonella enterica and Aspergillus niger and its effects on Zea mays colonization. Microbial Biotechnology, 7: 589–600.
Balbontín R*, Fiorini F, Figueroa-Bossi N, Casadesús J, Bossi L (2010) Recognition of heptameric seed sequence underlies multi-target regulation by RybB small RNA in Salmonella enterica. Mol Microbiol. 78(2):380-94.
Balbontín R*, Figueroa-Bossi N, Casadesús J, Bossi L (2008) Insertion hot spot for horizontally acquired DNA within a bidirectional small-RNA locus in Salmonella enterica. J Bacteriol. 190(11):4075-8.
Broadbent SE, Balbontin R, Casadesús J, Marinus MG, van der Woude M (2007) YhdJ, a nonessential CcrM-like DNA methyltransferase of Escherichia coli and Salmonella enterica. J Bacteriol. 189(11):4325-7.
Balbontín R*, Rowley G, Pucciarelli MG, López-Garrido J, Wormstone Y, Lucchini S, García- del Portillo F, Hinton JCD, Casadesús J (2006) DNA adenine methylation regulates virulence gene expression in Salmonella enterica serovar Typhimurium. J Bacteriol. 188(23):8160-8.
Figueroa-Bossi N, Lemire S, Maloriol D, Balbontín R, Casadesús J, Bossi L (2006) Loss of Hfq activates the SigmaE-dependent envelope stress response in Salmonella enterica. Mol Microbiol. 62(3):838-52.