| Autor: |
William da Fonseca Batistão D; Medical School (FAMED), Federal University of Uberlândia, Campus Umuarama, Uberlândia, Brazil., Amaral de Campos P; Laboratory of Molecular Microbiology, Biomedical Science Institute, Federal University of Uberlândia, Campus Umuarama, Uberlândia, Brazil., Caroline Camilo N; Laboratory of Molecular Microbiology, Biomedical Science Institute, Federal University of Uberlândia, Campus Umuarama, Uberlândia, Brazil., Royer S; Laboratory of Molecular Microbiology, Biomedical Science Institute, Federal University of Uberlândia, Campus Umuarama, Uberlândia, Brazil., Fuga Araújo B; Laboratory of Molecular Microbiology, Biomedical Science Institute, Federal University of Uberlândia, Campus Umuarama, Uberlândia, Brazil., Spirandelli Carvalho Naves K; Laboratory of Molecular Microbiology, Biomedical Science Institute, Federal University of Uberlândia, Campus Umuarama, Uberlândia, Brazil., Martins M; Institute for Biotechnology and Bioengineering, Centre of Biological Engineering, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal., Olívia Pereira M; Institute for Biotechnology and Bioengineering, Centre of Biological Engineering, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal., Henriques M; Institute for Biotechnology and Bioengineering, Centre of Biological Engineering, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal., Pinto Gontijo-Filho P; Laboratory of Molecular Microbiology, Biomedical Science Institute, Federal University of Uberlândia, Campus Umuarama, Uberlândia, Brazil., Botelho C; Institute for Biotechnology and Bioengineering, Centre of Biological Engineering, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal., Oliveira R; Institute for Biotechnology and Bioengineering, Centre of Biological Engineering, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal., Marques Ribas R; Laboratory of Molecular Microbiology, Biomedical Science Institute, Federal University of Uberlândia, Campus Umuarama, Uberlândia, Brazil. |
| Abstrakt: |
Biofilms plays an important role in medical-device-related infections. This study aimed to determine the factors that influence adherence and biofilm production, as well as the relationship between strong biofilm production and genetic determinants in clinical isolates of meticillin-resistant Staphylococcus aureus (MRSA). Fifteen strains carrying different chromosomal cassettes recovered from hospitalized patients were selected; five SCC mec II, five SCC mec III and five SCC mec IV. The SCC mec type, agr group and the presence of the virulence genes ( bbp, clfA, icaA, icaD, fnbB, bap, sasC and IS 256 ) were assessed by PCR. PFGE and multilocus sequence typing (MLST) techniques were also performed. The initial adhesion and biofilm formation were examined by quantitative assays. The surface tension and hydrophobicity of the strains were measured by the contact angle technique to evaluate the association between these parameters and adhesion ability. SCC mec III and IV strains were less hydrophilic, with a high value for the electron acceptor parameter and higher adhesion in comparison with SCC mec II strains. Only SCC mec III strains could be characterized as strong biofilm producers. The PFGE showed five major pulsotypes (A-E); however, biofilm production was related to the dissemination of one specific PFGE clone (C) belonging to MLST ST239 (Brazilian epidemic clonal complex). The genes agr I, fnbB and IS 256 in SCC mec III strains were considered as genetic determinants associated with strong biofilm-formation by an ica -independent biofilm pathway. This study contributes to the understanding of biofilm production as an aggravating factor potentially involved in the persistence and severity of infections caused by multidrug-resistant MRSA belonging to this genotype. |
