Premium
Encystation of Acanthamoeba castellanii : Dye uptake for assessment by flow cytometry and confocal laser scanning microscopy
Author(s) -
Connell C.,
Rutter A.,
Hill B.,
Suller M.,
Lloyd D.
Publication year - 2001
Publication title -
journal of applied microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.889
H-Index - 156
eISSN - 1365-2672
pISSN - 1364-5072
DOI - 10.1046/j.1365-2672.2001.01296.x
Subject(s) - library science , confocal laser scanning microscopy , biology , microbiology and biotechnology , computer science
Aims: To develop rapid means of distinguishing between cysts and trophozoites of the opportunistic pathogen, Acanthamoeba castellanii , the causative agent of keratitis. Methods and Results: Fluorescence of Congo Red, Calcoflor White was specific for the endocyst wall; trophozoites did not become fluorescent. The anionic oxonol dye, DiBAC 4 (3), did not penetrate the cytoplasmic membrane after short‐term (<5 min) exposure, whereas cysts are permeable and become fluorescent. Confocal scanning laser microscopy confirmed these properties and large populations of organisms were analysed by flow cytometry. Conclusions: These data provide a rapid alternative to traditional haemocytometer or plate counts for discrimination of trophozoites from cysts. Significance and Impact of the Study: Rapid and precise determination of the growth cycle of a dangerous ocular pathogen.