Abstract A bioactive polysaccharide from Ganoderma atrum (PSG-1-F0.2) was previously characterized as a hyper-branched acidic β-(1 → 3)-glucan with long β-(1 → 6)-glucose side chains. The conformational properties of PSG-1-F0.2 were systematically investigated by high performance size exclusion chromatography (HPSEC), light scattering, atomic force microscope (AFM) and molecular modeling techniques. Large aggregates were found when PSG-1-F0.2 dissolved in pure water, while 0.9% NaCl solution exhibited the ability to reduce/eliminate the aggregates. The weight average molecular weight (Mw), radius of gyration (Rg), hydrodynamic radius (Rh) and intrinsic viscosity [η] were determined as 12.73 kDa, 17.1 nm, 8.1 nm and 0.09 dL/g, respectively. The conformation analysis and AFM results together indicated that PSG-1-F0.2 exhibited as hyper-branched compact spherical conformation in 0.9% NaCl solution. The results of molecular modeling identified that long β-(1 → 6)-glucose side chain played an important role in the aggregation and spherical conformation of PSG-1-F0.2.

中文翻译：

---

通过光散射和分子建模从灵芝生物活性多糖的构象特性

摘要 灵芝生物活性多糖 (PSG-1-F0.2) 先前被表征为具有长 β-(1 → 6)-葡萄糖侧链的超支化酸性 β-(1 → 3)-葡聚糖。通过高效尺寸排阻色谱 (HPSEC)、光散射、原子力显微镜 (AFM) 和分子建模技术系统地研究了 PSG-1-F0.2 的构象特性。当 PSG-1-F0.2 溶解在纯水中时发现了大的聚集体，而 0.9% NaCl 溶液则表现出减少/消除聚集体的能力。重均分子量 (Mw)、回转半径 (Rg)、流体力学半径 (Rh) 和特性粘度 [η] 分别测定为 12.73 kDa、17.1 nm、8.1 nm 和 0.09 dL/g。构象分析和 AFM 结果共同表明 PSG-1-F0. 2 在 0.9% NaCl 溶液中表现出超支化的紧凑球形构象。分子建模结果表明，长 β-(1 → 6)-葡萄糖侧链在 PSG-1-F0.2 的聚集和球形构象中起重要作用。