Polysaccharides present in cultivated Teloschistes flavicans symbiosis: comparison with those of the thallus.
The chemical structures of polysaccharides present in aposymbiotically cultured myco- and photobionts of the lichen Teloschistes flavicans were determined, in order to compare them with those previously found in the intact thallus. The mycobiont was cultured on a solid Lilly and Barnett medium and the resulting colonies were freeze dried, defatted, and their polysaccharides were extracted successively with 2%, 10% and 30% aq. KOH, each at 100 degrees C. The extracts were neutralized (HOAc) and fractionated, giving rise to three homogeneous fractions, PFSK2 from 2% KOH, which contained a (1-->4),(1-->6)-linked alpha-glucan (1:1 ratio, pullulan), fraction PK10 from 10% KOH extraction, which was a linear (1-->3)-linked linear beta-glucan (laminaran), and fraction PK30 from 30% KOH extraction, being a branched (1-->3),(1-->6)-linked beta-glucan. The photobiont (Trebouxia sp. de Puymaly) was cultured in liquid nutrient medium, and after purification, a linear (1-->5)-linked beta-galactofuranan was characterized. The galactofuranan and the laminaran were not present in the symbiotic thallus, in contrast to the glucans, showing that the mycobiont alone produces them without participation of the photobiont.
Ruthes
Andrea C
AC
Departamento de Bioquímica e Biologia Molecular, Universidade Federal do Paraná, Curitiba, PR, Brazil.
Komura
Dirce L
DL
Carbonero
Elaine R
ER
Cordeiro
Lucimara M C
LM
Reis
Rodrigo A
RA
Sassaki
Guilherme L
GL
Gorin
Philip A J
PA
Iacomini
Marcello
M
D001203:Ascomycota / Q000166:cytology / Q000254:growth & development*; D002236:Carbohydrate Conformation; D056890:Eukaryota / Q000166:cytology / Q000254:growth & development; D008011:Lichens / Q000166:cytology / Q000254:growth & development; D011134:Polysaccharides / Q000096:biosynthesis*; D013559:Symbiosis / Q000502:physiology*
D011134:Polysaccharides