Microbial biotechnology and host-pathogen interaction
Prof. Dr.
Juárez, Antonio
Group Leader
Ed. Hèlix | Baldiri Reixac 15-21 | 08028 | Barcelona
Email : ajuarez
ibecbarcelona.eu
Research Topics
Pathogenic bacteria / Nucleoid-associated proteins / Ribonucleotide Reductases / Bacterial biofilms / Single cell studies / Atomic Force Microscopy
1. Structure and function of bacterial proteins that modulate virulence expression
Protein–protein and protein–DNA interactions play key roles in the ability of virulent bacteria to adapt to the host environment and cause disease. Two groups of proteins are currently the focus of our research: nucleoid-associated proteins (NAPs) that contribute to DNA architecture and modulate gene expression, and ribonucleotide reductases (RNRs), which are key enzymes in all living organisms providing the nucleotide precursors for DNA replication and repair. In the former group, we are interested in unravelling the role played by two of these proteins—Hha and H-NS—in the regulation of virulence. In the case of the latter group, our current research objectives are to analyze the importance of bacterial RNRs in pathogenesis and the molecular mechanisms of gene expression and to identify new specific RNR inhibitors. Owing to their essential function, these enzymes offer excellent potential for combating bacterial infection.
Representative portion of a Salmonella typhimurium microarray.
2. Application of nanotools of bacterial biotechnology
2.1. Dielectrophoresis. We have previously shown that dielectrophoresis can be a valuable tool for bacterial cell sorting and characterization. We are currently using different chip designs (2D and 3D carbon electrodes) with three different objectives: a) to study the effect of electric fields on bacterial cell physiology; b) to evaluate the ability of chip designs to capture and release bacterial cells, and c) to concentrate bacterial pathogens and facilitate their detection.
2.2. Atomic force microscopy (AFM). Conventional AFM approaches have been shown to be powerful techniques for characterizing both biomaterials and biomolecules. In a joint project with the Nanoscale Bioelectrical Characterization group (page 41), we intend to use electrical-AFM to characterize the bacterial cell envelope. We also plan to use this approach to analyze further the location of bacterial proteins of unknown function predicted to be present on the bacterial cell envelope.
Structural superposition of NrdA (class I) and NrdD (class III) subunits of ribonucleotide reductase.
