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Photodynamic damage predominates on different targets depending on cell growth phase of Candida albicans.
Baptista, Alessandra; Sabino, Caetano P; Núñez, Silvia C; Miyakawa, Walter; Martin, Airton A; Ribeiro, Martha S.
Afiliação
  • Baptista A; Center for Lasers and Applications, Nuclear and Energy Research Institute, IPEN - CNEN/SP, São Paulo, SP, Brazil; Biomedical Engineering Post-Graduation Program, Universidade Brasil, São Paulo, SP, Brazil.
  • Sabino CP; Center for Lasers and Applications, Nuclear and Energy Research Institute, IPEN - CNEN/SP, São Paulo, SP, Brazil; Department of Microbiology, Institute for Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil.
  • Núñez SC; Biomedical Engineering Post-Graduation Program, Universidade Brasil, São Paulo, SP, Brazil.
  • Miyakawa W; Photonics Division, Institute for Advanced Studies, São José dos Campos, SP, Brazil.
  • Martin AA; Biomedical Engineering Post-Graduation Program, Universidade Brasil, São Paulo, SP, Brazil.
  • Ribeiro MS; Center for Lasers and Applications, Nuclear and Energy Research Institute, IPEN - CNEN/SP, São Paulo, SP, Brazil. Electronic address: marthasr@usp.br.
J Photochem Photobiol B ; 177: 76-84, 2017 Dec.
Article em En | MEDLINE | ID: mdl-29107205
Photodynamic inactivation (PDI) has been reported to be effective to eradicate a wide variety of pathogens, including antimicrobial-resistant microorganisms. The aim of this study was to identify the potential molecular targets of PDI depending on growth phase of Candida albicans. Fungal cells in lag (6h) and stationary (48h) phases were submitted to PDI mediated by methylene blue (MB) combined with a (662±21) nm-LED, at 360mW of optical power. Pre-irradiation time was 10min and exposure times were 12min, 15min and 18min delivering radiant exposures of 129.6J/cm2, 162J/cm2 and 194.4J/cm2, respectively, on a 24-well plate of about 2cm2 at an irradiance of 180mW/cm2. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), atomic force spectroscopy (AFS) and Fourier transform infrared spectroscopy (FT-IR) were employed to evaluate the photodynamic effect in young and old fungal cells following 15min of irradiation. Morphological analysis revealed wrinkled and shrunk fungal cell membrane for both growth phases while extracellular polymeric substance (EPS) removal was only observed for old fungal cells. Damaged intracellular structures were more pronounced in young fungal cells. The surface nanostiffness of young fungal cells decreased after PDI but increased for old fungal cells. Cellular adhesion force was reduced for both growth phases. Fungal cells in lag phase predominantly showed degradation of nucleic acids and proteins, while fungal cells in stationary phase showed more pronounced degradation of polysaccharides and lipids. Taken together, our results indicate different molecular targets for fungal cells in lag and stationary growth phase following PDI.
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Texto completo: 1 Coleções: 01-internacional Base de dados: MEDLINE Assunto principal: Candida albicans / Fármacos Fotossensibilizantes / Luz Idioma: En Revista: J Photochem Photobiol B Assunto da revista: BIOLOGIA Ano de publicação: 2017 Tipo de documento: Article País de afiliação: Brasil País de publicação: Suíça

Texto completo: 1 Coleções: 01-internacional Base de dados: MEDLINE Assunto principal: Candida albicans / Fármacos Fotossensibilizantes / Luz Idioma: En Revista: J Photochem Photobiol B Assunto da revista: BIOLOGIA Ano de publicação: 2017 Tipo de documento: Article País de afiliação: Brasil País de publicação: Suíça