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

EGEA AL; BARCUDI D; NICOLA JP; BOCCO JL; SOLA C

Córdoba

Congreso; 52th Annual Meeting Argentine Society for Biochemistry and Molecular Biology; 2016

SAIB

CIBICI?CONICET. Fac. de Cs. Químicas, UNC. E-mail: aegea@fcq.unc.edu.arMethicillin-resistantStaphylococcus aureus(MRSA) causes both hospital (HA) and community-acquired (CA) infections. In order toinvestigate the relationship between the epidemiological success of epidemic MRSA clones and their capacity to persist on anenvironmental inert surface, the survival and genes expression during the persistence on melamine surface were analyzed. Volumes of100 μL of bacterial suspensions (1011?1012UFC/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 40 days to perform the colony counts and for RNA preparation. The genesexpression (spaA, fnbpA, fnbpB, hla, psmA1A2, IsdD, agrA, RNAIII) was analyzed by qRT-PCR. All MRSA clones showed a similarsurvival 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).isdDtranscriptionwas increased about 40- and 35-fold in ST5-I and C-ST5-IVnv clones, respectively. These results suggest thatisdDcould be involved inthe persistence onto inert surfaces in the hospital setting of both epidemic MRSA clones