SURVIVAL AND GENES EXPRESSION OF MRSA EPIDEMIC CLONES ON AN ENVIRONMENTAL INERT SURFACE

ANA L EGEA; DANILO BARCUDI; NICOLA JUAN PABLO; BOCCO, JOSE LUIS; CLAUDIA SOLA

Cordoba

Congreso; Reunión Anual de la Sociedad Argentina de Investigación en Bioquímica y. Biología Molecular; 2016

Sociedad Argentina de Investigación en Bioquímica y. Biología Molecular

Methicillin-resistant Staphylococcus aureus (MRSA) causes both hospital (HA) and community-acquired (CA) infections. In order to investigate the relationship between the epidemiological success of epidemic MRSA clones and their capacity to persist on an environmental inert surface, the survival and genes expression during the persistence on melamine surface were analyzed. Volumes of 100 μL of bacterial suspensions (1011?1012 UFC/ml in saline solution, SS) of isolates representatives the epidemic clones (CAMRSA: ST5-IV, ST30-IV and USA300-ST8-IV, HAMRSA: ST5-I, ST5-IVnv, ST239-IIIA and ST5-II) were spotted onto a melamine surface. Dried MRSA were collected with SS at 24h; 10; 25 and 40days to perform the colony counts and for RNA preparation. The genes expression (spaA, fnbpA, fnbpB, hla, psmA1A2, IsdD, agrA, RNAIII) was analyzed by qRT-PCR. All MRSA clones showed a similar survival tendency, decreasing progressively towards 40 day, being higher (p<0,05) in ST5-I and C-ST5-IVnv clones than the others. The genes expression levels by each clone at 10 day, were higher than those in its initial condition 24h (p<0,001). IsdD transcription was increased about 40- and 35-fold in ST5-I and C-ST5-IVnv clones, respectively. These results suggest that isdD could be involved in the persistence onto inert surfaces in the hospital setting of both epidemic MRSA clones