In fungal cells, there is evidence of some functions of ecto-ATPase (Zhong et al., 2000; Junior et al., 2005; Collopy-Junior et al., 2006; Kiffer-Moreira et al., 2010), but little information is available about the activity of ecto-5′-nucleotidase and its product, adenosine. Identification of the physiological role of this enzyme would contribute to understanding the biochemical aspects of host–parasite interactions involving C. parapsilosis. We would like to thank Ribociclib price Ms Fatima Regina de Vasconcelos Goulart for preparation of fungal cultures and Mr Fabiano Ferreira Esteves and Ms Rosangela Rosa de Arau´jo for excellent technical assistance. This work was supported by grants from the Brazilian
Agencies Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) and Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ). “
“The main α-glucan synthesized by lichens of the genera Ramalina in the symbiotic state is isolichenan. This polysaccharide was not found in the aposymbiotically cultivated symbionts. It is still unknown if this glucan is produced by the mycobiont only in the presence of a photobiont, in a lichen thallus, or if the isolichenan suppression is influenced by the composition of
culture medium used in its aposymbiotic cultive. Consequently, the latter hypothesis is tested in this study. Cultures of the mycobiont Ramalina complanata were obtained from germinated ascospores and cultivated on 4% glucose Lilly and Barnett medium. Freeze-dried Selleck BMS354825 colonies were defatted and their carbohydrates extracted successively with hot water and aqueous 10% KOH, each at 100 °C. The polysaccharides nigeran, laminaran and galactomannan were liberated, along
with a lentinan-type β-glucan and a heteropolysaccharide (Man : Gal : Glc, 21 : 28 : 51). Nevertheless, the α-glucan isolichenan was not found in the extracts. It follows that it was probably a symbiotic product, synthesized Non-specific serine/threonine protein kinase by the mycobiont only in this particular microenvironment, in the presence of the photobiont in the lichen thallus. A discussion about polysaccharides found in the symbiotic thallus as well as in other aposymbiotic cultivated Ramalina mycobionts is also included. The lichen thallus, the symbiotic phenotype of lichen-forming fungi in association with their photobiont (algae and/or cyanobacteria), contains considerable amounts of polysaccharide. Although this symbiotic nature was first revealed in 1867, the development of a lichen thallus is often so integrated that it has been perceived and studied as a single organism until quite recently (Nash, 2008; Lutzoni & Miadlikowska, 2009). Investigations on lichen polysaccharides were carried out using material extracted from the entire thallus (Gorin & Iacomini, 1984, 1985; Gorin et al., 1993; Teixeira et al., 1995; Olafsdottir & Ingólfsdottir, 2001), with no mention of the origin of component polymers (fungal partner or photobiont).