Ultrastructural architecture of colonies of different morphologies produced by phenotypic switching of a clinical strain of Candida tropicalis and biofilm formation by variant phenotypes

► We investigated switching event in a Candida tropicalis clinical strain. ► The ultrastructural architecture of different phenotypes and biofilm were characterized. ► The biofilm-forming ability varied among the switch phenotypes. ► First time SEM was used to verify the architecture of whole Candida colonies at ultrastructural level. ► Extracellular material was correlated with complex colony architecture.