Mechanistic aspects of the photodynamic inactivation of Candida albicans induced by cationic porphyrin derivatives

摘要: Abstract Photodynamic inactivation of Candida albicans produced by 5-(4-trifluorophenyl)-10,15,20-tris(4- N , -trimethylammoniumphenyl)porphyrin (TFAP 3+ ), 5,10,15,20-tetrakis(4- (TMAP 4+ ) and -methylpyridyl)porphyrin (TMPyP was investigated to obtain insight about the mechanism cellular damage. In solution, absorption spectroscopic studies showed that these cationic porphyrins interact strongly with calf thymus DNA. The electrophoretic analysis indicated photocleavage DNA induced TFAP took place after long irradiation periods (>5 h). contrast, TMAP a marked reduction in band 1 h irradiation. C. albicans ∼3.5 log decrease survival when cell suspensions (10 7  cells/mL) were incubated 5 μM photosensitizer irradiated for 30 min visible light (fluence 162 J/cm 2 ). After this treatment, modifications genomic isolated from cells not found electrophoresis. Furthermore, transmission electron microscopy structural changes appearance low density areas into irregularities barriers. However, photodamage envelope insufficient cause release intracellular biopolymers. Therefore, cytoplasmic biomolecules alteration barriers could be mainly involved photoinactivation.