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leaD researcher
García López, Ernesto
agencia estatal consejo Superior de Investigaciones Científicas
Centro de Investigaciones Biológicas
Ramiro de Maeztu, 9 28040 Madrid
(+34) 91 837 31 12 [email protected] group website
GROUP MEMBERS
Staff members: Ruiz García, Susana
Associated members: Díez Martínez, Roberto | Domenech Lucas, Mirian | García González, Pedro | Moscoso Naya, Miriam | Ramos Sevillano, Elisa | Yuste Lobo, José Enrique
Main lines of research
It is noteworthy that 65–80% of chronic bacterial infections are caused by microbes growing in biofilms. The tolerance of these communities to antibiotic therapy is well known. Firm evidence also links biofilms both
to chronic and acute lung infections, as exemplified by cystic fibrosis and ventilator-associated pneumonia, respectively. The nasopharynx and the lungs are involved in constant and essential chemical signaling
among the local microbiota, and between this and both local and systemic tissues critical to human physiology. The healthy nasopharynx and lungs are colonized by different microorganisms that form mixed biofilms: 1) encapsulated pneumococci associate with non-typeable pneumococci (NTPn), strains of S. pseudopneumoniae and/or non-typeable H. influenzae in the nasopharynx; 2) bacteria belonging to the phyla Firmicutes (mainly Streptococcus), Proteobacteria, and Bacteroidetes in lungs. We are currently studying the requirements (microbiological and otherwise) for in vitro mixed biofilm formation between S. pneumoniae and other bacterial pathogens.
Pathogenic bacteria are becoming increasingly resistant to the classic antibiotics used with much success in recent decades. Among the few alternatives currently envisaged for treating this problem are phage endolysins (also called enzybiotics), which are modular enzymes that hydrolyze specific peptidoglycan bonds of susceptible bacteria. In the laboratory we test new endolysins mainly targeted against respiratory pathogens, obtained from phage origin or by construction of chimeras resulting from the fusion of different functional domains. These enzymes are very effective against either planktonic cultures or biofilms. Validation of in vitro
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PROGRAMMES
Infectious Respiratory Diseases