First report on polysaccharides of Asterochloris and their potential role in the lichen symbiosis

Lichen Polysaccharides

“…Later Cordeiro et al (2005Cordeiro et al ( , 2007Cordeiro et al ( , 2008, found that, dissimilarities between the polysaccharides extracted from the cultivated photobionts Trebouxia and Asterochloris with those from their respective lichens could indicate that the photobiont or mycobiont was responsible for these differences. Galactoglucomannans were isolated from the mycobiont of (Cordeiro et al, 2005).…”

“…It consisted of (1→3)-linked galactofuranosyl units with side chains of galactofuranosyl units 5-O and 6-Osubstituted, as well rhamnopyranosyl units 2-O, 3-O and 2,3-di-O-substituted at position 6. Nonreducing end units were composed of Xylose (Cordeiro et al, 2007). In 2006, (1→3)-and (1→6)-linked -glucans, namely laminaran and pustulan and galactofuranomannan which have a main chain of (1→6)-linked -mannopyranosyl residues, partially substituted at O-2, O-4 were isolated from another lichen Umbilicaria mammulata (Carbonero et al, 2006) Coccomyxa mucigena of the lichen Peltigera aphthosa was thought to be the origin of this heteropolysaccharide since the lichen thallus yielded a polysaccharide of different structure.…”

“…Lichen polysaccharides, can also be used as a taxonomic tool to differentiate some lichen species, since some of the heteropolysaccharides and their chemical characters are unique to certain groups of lichens (Carbonero et al, 2006 andCordeiro et al, 2007). Further, the polysaccharides content of the lichen photobiont may be used as a marker in algal symbiont taxonomy (Cordeiro et al, 2007).…”

“…Further, the polysaccharides content of the lichen photobiont may be used as a marker in algal symbiont taxonomy (Cordeiro et al, 2007).…”

Structural characterisation of a new O-methylated heteroglycan, colleman, from the cyanolichen Collema flaccidum

“…Lichen polysaccharides, which can be isolated in high yield, such as the glucans and galactomannans, are generally considered to be of fungal origin (Gorin, Baron, & Iacomini, 1988;Gorin, Baron, Silva, Teixeira, & Iacomini, 1993). This has been supported by comparing the polysaccharides isolated from the intact lichen with those produced by the aposymbiotically cultured mycobionts and photobionts (Cordeiro, de Oliveira, Buchi, & Lacomini, 2008;Cordeiro, Sassaki, & Iacomini, 2007;Cordeiro, Stocker-Worgotter, Gorin, & Iacomini, 2004;Ruthes et al, 2008;Takahashi, Takeda, & Shibata, 1979).…”