title: Fatty acid composition of the tropical lichen Teloschistes flavicans and its cultivated symbionts.
abstract: Fatty acid components, in both the free and combined form of the intact tropical lichen Teloschistes flavicans, and its isolated photobiont and mycobiont, were analyzed by GC-MS of derived methyl esters. Its rDNA analysis confirmed that the isolated cultured symbionts belong to the genera Trebouxia and Teloschistes, respectively. The fatty acid composition of the lichen did not correspond to those found in the isolated symbionts, suggesting that the fatty acid metabolism is markedly influenced by the symbiosis. Differences in the fatty acid composition in the lichen were observed during the summer (27 degrees C), when the main fatty acids were saturated and in the winter (22 degrees C) when an increase of unsaturated fatty acids occurred. Similar differences of composition were also observed for the cultured mycobiont at different temperatures. The increase in the unsaturation level at low temperatures would maintain the membrane fluidity. Our results are the first on the fatty acids of a tropical lichen and suggest that it is sensitive to small temperature variations, which influences its saturated and unsaturated fatty acid composition.
authors.affiliation: Departamento de Bioquímica, Universidade Federal do Paraná, Curitiba, PR, Brazil.
authors.forename: Rodrigo Arantes
authors.initials: RA
authors.lastname: Reis
authors.forename: Marcello
authors.initials: M
authors.lastname: Iacomini
authors.forename: Philip Albert James
authors.initials: PA
authors.lastname: Gorin
authors.forename: Lauro Mera
authors.initials: LM
authors.lastname: de Souza
authors.forename: Martin
authors.initials: M
authors.lastname: Grube
authors.forename: Lucimara Mach Cortes
authors.initials: LM
authors.lastname: Cordeiro
authors.forename: Guilherme Lanzi
authors.initials: GL
authors.lastname: Sassaki
mesh_terms: D000217:Acyltransferases; D001203:Ascomycota / Q000737:chemistry / Q000235:genetics / Q000254:growth & development; D001938:Brazil; D000460:Chlorophyta / Q000737:chemistry / Q000235:genetics / Q000254:growth & development; D002849:Chromatography, Gas; D004952:Esters / Q000032:analysis; D005227:Fatty Acids / Q000032:analysis*; D005231:Fatty Acids, Unsaturated / Q000032:analysis; D008011:Lichens / Q000737:chemistry / Q000302:isolation & purification / Q000502:physiology*; D013058:Mass Spectrometry; D012621:Seasons; D013559:Symbiosis; D013696:Temperature; D014329:Tropical Climate
chemical_list: D004952:Esters; D005227:Fatty Acids; D005231:Fatty Acids, Unsaturated; D000217:Acyltransferases; C074049:fatty acid modifying enzyme