Osaku Clarice A, Sassaki Guilherme L, Zancan Glaci T, Iacomini Marcello
Departamento de Bioquímica, Universidade Federal do Paraná, C P 19046, 81531-990, PR, Curitiba, Brazil.
FEMS Microbiol Lett. 2002 Nov 5;216(2):145-9. doi: 10.1111/j.1574-6968.2002.tb11428.x.
The ectomycorrhizal hymenomycete Thelephora terrestris was grown in synthetic pure culture and the production of extracellular polysaccharide was monitored. The exopolysaccharides were prepared by ethanol precipitation and then fractionated into two components using a DEAE-Sepharose column. A neutral fraction (NeP) was fractionated on Sepharose CL-6B, which resulted in three peaks: NeP1, NeP2 and NeP3. NeP1 was filtered through an exclusion membrane and two polysaccharides were obtained (fractions: NeA, NeB). Fraction NeB was submitted to methylated derivatives and 1H-, 13C- and 2D NMR spectroscopic analyses. These analyses showed a main chain of a (1-->6)-linked alpha-D-Manp units substituted at O-2 by a variety of side chains containing alpha-Fucp, beta-Xylp and beta-Galp residues. The main fraction corresponds to mannan as shown by methylation analysis. Size exclusion chromatography (HPSEC-MALLS) of fraction NeB showed a main component of 15.0 kDa. It contained mannose, galactose, fucose and xylose in a molar ratio of 50:29:11:10. The fractions NeP2 and NeP3 were characterised as a (1-->6)-linked beta-glucan (pustulan) and (1-->3)-linked beta-glucan, respectively.
外生菌根担子菌土生梭柄盘菌在合成纯培养物中生长，并监测细胞外多糖的产生。胞外多糖通过乙醇沉淀制备，然后使用DEAE-琼脂糖柱分离成两个组分。中性组分（NeP）在琼脂糖CL-6B上进行分离，得到三个峰：NeP1、NeP2和NeP3。NeP1通过排阻膜过滤，得到两种多糖（组分：NeA、NeB）。组分NeB进行甲基化衍生物以及1H-、13C-和二维核磁共振光谱分析。这些分析表明，主链由α(1→6)连接的α-D-甘露糖基单元组成，在O-2位被含有α-岩藻糖基、β-木糖基和β-半乳糖基残基的各种侧链取代。如甲基化分析所示，主要组分对应于甘露聚糖。组分NeB的尺寸排阻色谱（HPSEC-MALLS）显示主要成分的分子量为15.0 kDa。它含有甘露糖、半乳糖、岩藻糖和木糖，摩尔比为50:29:11:10。组分NeP2和NeP3分别被鉴定为α(1→6)连接的β-葡聚糖（块菌多糖）和α(1→3)连接的β-葡聚糖。
