Formação de biofilmes com cepas de micobactérias de crescimento rápido de fenótipos liso e rugoso

• Ano de defesa: 2010
• Autor(a) principal: Lima, Jéssica Maria Moreno Rodrigues de [UNIFESP]
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de São Paulo (UNIFESP)
• Palavras-chave em Português: Fontes ambientais; Biofilmes; Fenótipo; Surtos de doenças; Micobactérias não tuberculosas
• Link de acesso: http://repositorio.unifesp.br/handle/11600/9656

Non-Tuberculous Mycobacteria (NTM) are ubiquitously distributed bacteria equipped to support different temperatures and lack of nutrients. They also show resistance to diverse disinfectants and antimicrobials. Several Mycobacterium species have been associated to biofilms in surgical equipment and water systems in hospital environment and this has important implications in epidemiology, survival in the environment and resistance to biocides and antimicrobials. Rapidly-Growing Mycobacteria (RGM) have been associated to outbreaks of infections in invasive procedures, as plastic and ophthalmological surgeries, laparoscopic surgeries and cosmetic procedures. The objective of this study was to investigate the capacity of RGM with different phenotypes (smooth and rough), especially Mycobacterium massiliense, of forming biofilms, by comparison of isolates related to outbreaks with isolates not related to outbreaks. Twenty-seven isolates were analyzed with respect to adhesion to different abiotic supports in the presence of different solutions. Growth curves were obtained using resazurin as indicator. The production of glycopeptidolipids and polysaccharides in the cell wall and the sliding motility in semisolid medium were also analyzed. Bacteria adhered to solid supports were visualized through optical and electronic microscopes. Results obtained with outbreak-related isolates and isolates not related to outbreaks were similar. The presence of 2% glutaraldehyde inhibited the adhesion of rough colony phenotype bacteria to plastic. With these results we concluded that biofilm formation capacity cannot differentiate outbreak-related isolates from isolates not related to outbreaks, or rough from smooth phenotype bacteria. It is possible that a collection of factors may facilitate the selection of particular strains more adapted to cause infections and with potential to originate outbreaks. The identification and characterization of these factors could contribute to the control of new outbreaks and to the epidemiological surveillance of infections by these opportunistic pathogens.