title: Photosensitization of Colpoda inflata cysts by meso-substituted cationic porphyrins.
abstract: Colpoda inflata cysts accumulate significantly large amounts of meso-substituted cationic porphyrins, including meso-tetrakis(N-methyl-4-pyridyl)porphine (TMP-C1) and its mono-N-methyldecyl (TMP-C10) and -tetradecyl (TMP-C14) analogues upon incubation for 1 h with 1-48 microM porphyrin concentrations. All three porphyrins at concentrations greater than 10 microM exhibited a significant toxicity toward the cysts, in particular lowering the degree of excystment. Upon visible light irradiation of the porphyrin-loaded cysts, extensive photodamage was observed even in the presence of 1 microM porphyrin, as shown by light microscopy observations and counting of vegetative emerging cells The presence of one decyl or tetradecyl hydrocarbon chain caused about 10-fold enhancement of the phototoxic effects.
authors.affiliation: National Institute of Laser Enhanced Science, Cairo University, Egypt.
authors.forename: Kawser
authors.initials: K
authors.lastname: Kassab
authors.forename: Thameur
authors.initials: T
authors.lastname: Ben Amor
authors.forename: Giulio
authors.initials: G
authors.lastname: Jori
authors.forename: Olimpia
authors.initials: O
authors.lastname: Coppellotti
mesh_terms: D000818:Animals; D002412:Cations; D056890:Eukaryota / Q000187:drug effects* / Q000528:radiation effects; D008853:Microscopy; D017319:Photosensitizing Agents / Q000494:pharmacology*; D011166:Porphyrins / Q000494:pharmacology*
chemical_list: D002412:Cations; D017319:Photosensitizing Agents; D011166:Porphyrins