“…The chloromethyl group reacts with thiols such as glutathione producing fluorescent conjugates that are membrane impermeable and so are retained within the vacuole lumen (Haugland, 1995;Cole et al, 1997). Similarly, a set of fluorescent vacuole markers based on 6-carboxyfluorescein diacetate (CFDA) and its derivatives (CDCFDA, 5-[and 6-] carboxy-2′, 7′-dichlorofluorescein diacetate, cDFFDA, and Oregon Green 488 carboxylic acid diacetate) have been used to visualise vacuoles in a range of fungi such as C. albicans (Veses et al, 2009b), P. tinctorius (Hyde et al, 2002), Paxillus involutus (Tuszynska, 2006), P. velutina (Darrah et al, 2006;Fricker et al, 2008;Zhuang et al, 2009), A. nidulans (Peñalva, 2005), Gigaspora margarita (Saito et al, 2004), S. cerevisiae (Shiflett et al, 2004), U. maydis (Torralba and Heath, 2002) and C. neoformans (Harrison et al, 2002). They work by the same principle as CMAC, and are colourless non-polar compounds which readily diffuse across cell membranes.…”