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Most relevant scientific articles
• FerraNdIz M.-J., de La caMpa a.G. . The fluoroquinolone levofloxacin triggers the transcriptional activa- tion of iron transport genes that contribute to cell death in streptococcus pneumoniae . Antimicrobial Agents and Chemotherapy . 2014;58(1):247-257 .
• MartIN-GaLIaNo a.J., YuSte J., cerceNado M.I., de La caMpa a.G. . Inspecting the potential physiological and biomedical value of 44 conserved uncharacterised proteins of Streptococcus pneumoniae . BMC Genomics . 2014;15(1):- .
• ardaNuY c., de La caMpa a.G., GarcIa e., FeNoLL a., caLataYud L., cerceNado e. et al . Spread of strepto- coccus pneumoniae serotype 8-st63 multidrug-resistant recombinant clone, Spain . Emerging Infec- tious Diseases . 2014;20(11):1848-1856 .
• Lopez e., doMeNech a., FerraNdIz M.-J., FrIaS M.J., ardaNuY c., raMIrez M. et al . Induction of prophages by fluoroquinolones in Streptococcus pneumoniae: Implications for emergence of resistance in genetica- lly-related clones . PLoS ONE . 2014;9(4):- .
• doMeNech a., tIrado-VeLez J.M., FeNoLL a., ardaNuY c., YuSte J., LINareS J. et al . Fluoroquinolone-resistant pneumococci: Dynamics of serotypes and clones in Spain in 2012 compared with those from 2002 and 2006 . Antimicrobial Agents and Chemotherapy . 2014;58(4):2393-2399 .
Highlights
Institution: Instituto de Salud Carlos III Contact: Centro Nacional de Microbiología · Campus Majadahonda . Ctra .Majadahonda-Pozuelo km 2 .200 . Madrid . · Phone: (+34) 91 822 39 44 · E .mail: agcampa@isciii .es
PROJECTS
• We have characterized a global transcriptomic response of Streptococcus pneumoniae under fluoro- quinolone treatment . Such a response has revealed an increase in the reactive oxygen species that contribute to levofloxacin lethality . These effects occur mainly by the activation of an iron transport . The possibility to increase fluoroquinolones efficacy by elevating the levels of intracellular iron remains open .
• We have performed the functional identification of 44 hypothetical proteins of S. pneumoniae. A new antibacterial target has been identified . Five proteins seemed to be virulence factors .
• We have performed an epidemiological study of fluoroquinolone resistance in S. pneumoniae of year 2012 and compared the data with our previous studies of 2002 and 2006 . Fluoroquinolone-resistance has been stabilized in 2 .3%, even when levofloxacin consumption has increased . We have detected changes both in serotypes and in genotypes distributions as a consequence of vaccination .
• We have detected the spread of a pre-existent multi-drug resistant clone, 8-ST63. This clone has been originated by the acquisition of the capsular genes of serotype 8 from clone 8-ST53 . The new clone 8-ST63 has been identified as a cause of invasive disease in Spain . An increase in fluoroquinolone resistance would occur by the expansion of these kinds of clones .
• We have characterized the induction of bacteriophages by fluoroquinolones in S. pneumoniae. Re- sistant isolates carried less functional prophages than the susceptible ones . Two isogenic strains, one lysogen and the other non-lysogen were treated with subinhibitory fluoroquinolone concentrations . Resistant mutants only emerged in the non-lysogen strain . These results are compatible with the lysis of lysogenic isolates receiving fluoroquinolones before the development of resistance and explain the inverse relation between presence of inducible prophages and fluoroquinolone resistance .
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