Maria Soledad Ramirez


Photograph of Maria Soledad Ramirez Identification and characterization of antibiotic resistance mechanisms, their dissemination, evolution and impact in morbidity and mortality of bacterial infections

We are in the midst of a dramatic antibiotic resistance outbreak that has spread across the world. The World Health Organization has recently identified this problem as a public health priority ( Research on the different causes of antibiotic resistance in clinical and non-clinical environments is urgently required to develop strategies to contain or overcome this problem. Our laboratory focuses on identifying mechanisms of antibiotic resistance, and understanding their evolution, means of dissemination across different genera, and impact in the morbidity and mortality of bacterial infections.

We place special emphasis on Acinetobacter baumannii, an important cause of high mortality nosocomial infections worldwide. A. baumannii’s infections are becoming increasingly difficult to treat, and in some cases they are untreatable as there are no antibacterial options left. The rapid increase in antibiotic resistance is due to the extreme genome plasticity of A. baumannii. Therefore, understanding of the molecular mechanisms by which this bacterium acquires and exchanges genetic information is to understand the physiology and virulence of this bacterium to devise new treatments.

Considering that A. baumannii is one of the most troublesome pathogens for its remarkable capability to acquire antibiotic resistance, explore the genetic basis of the antibiotic resistance; its acquisition and its dissemination will help to clarify the mechanisms that are playing a role not only in the development of antibiotic resistance, but also in the acquisition of the new determinants that allow A. baumannii to survive in extreme environments and drives to genome diversification.

Selected publications (Click for full list - coming soon)

Almuzara M, Traglia GM, Krizova L, Barberis C, Montana S, Bakai R, Tuduri A, Vay C, Nemec A, Ramirez MS. A taxonomically unique Acinetobacter strain with proteolytic and hemolytic activities recovered from a patient with a soft tissue injury. J. Clin. Microbiol. 2015. 53: 349-351

Traglia GM, Chua K, Centrón D, Tolmasky ME, Ramírez MS. Whole-genome sequence analysis of the naturally competent Acinetobacter baumannii clinical isolate A118. Genome Biol Evol. 2014 Aug 26;6(9):2235-2239

Svilacoba, E., Almuzara M., Gulone L., Rodriguez R, Pallone E., Bakai R., Centrón D, Ramírez M.S. Outbreak of extensively drug-resistant Acinetobacter baumannii indigo-pigmented strains. J. Clinical Microbiol. 2013. 51: 3726-3730

M. S. Ramirez, T. R. Parenteau, D. Centrón, and M. E. Tolmasky. Functional Characterization of Tn1331 Gene Cassettes. Journal of Antimicrobial Chemotherapy 2008 62 669-673

Vilacoba E., Almuzara M., Gulone. L, Traglia G., Figueroa S.A., Sly G., Fernández A., Centrón D., Ramírez M.S. Emergence and spread of tet(B)::ISCR2 plasmid-borne in minocycline resistance Acinetobacter baumannii isolates. Antimicrob Agents Chemother. 2013. 57: 651-654

Ramirez M.S., Adams M.D., Bonomo R.A., Centrón D., and Tolmasky M.E. Genomic Analysis of Acinetobacter baumannii A118 by Comparison of Optical Maps: Identification of Structures Related to its Susceptibility Phenotype. Antimicrob Agents Chemother. 2011. 55:1520-1526