title: Structure and chain conformation of a neutral intracellular heteropolysaccharide from mycelium of Paecilomyces cicadae.
abstract: A neutral heteropolysaccharide (PCIPS2) was isolated and purified from mycelium of Paecilomyces cicadae, which was investigated to be mainly composed of D-mannose, L-rhamnose, 3-O-methyl-D-galactose, D-glucose and D-galactose with a molar ratio of 47.9:3.1:6.4:0.9:0.8. It had a backbone of 1,4-linked α-L-Rhap residues and 1,6-linked α-D-Manp residues with branches at O-3 of α-D-Manp residues. Its side chain was comprised of minor terminal β-D-glucose and 1,4-linked α-3-O-Me-D-Galp residues terminated by α-D-galactose. Furthermore, its chain information on the values of weight-average molar mass (Mw), root mean square radius ([Formula: see text]), hydrodynamic radius (Rh) and intrinsic viscosity ([η]) for PCIPS2 were analyzed to be 3.09 × 10(4)g/mol, 7.8 nm, 3.6 nm and 8.5 mL/g, respectively. The structural exponent α of 0.57 indicated that PCIPS2 existed as a flexible chain conformation with a coil-like structure in 0.1M NaNO3 at 25 °C. In terms of known theory for worm-like chains, the model parameters for PCIPS2 were as following: molar mass per unit contour length (ML) = 379 nm(-1), persistence length (q) = 0.74 nm and hydrodynamic diameter of cylinder (d) = 0.82 nm, which were further evidenced by atomic force microscopy (AFM).
authors.affiliation: The Key Laboratory of Biochemical Utilization of Zhejiang Province, Zhejiang Forestry Academy, Hangzhou 310023, China; Institute of Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou 310058, China.
authors.forename: Chao-yang
authors.initials: CY
authors.lastname: Wei
authors.affiliation: Institute of Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou 310058, China.
authors.forename: Wei-qi
authors.initials: WQ
authors.lastname: Li
authors.affiliation: Institute of Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou 310058, China.
authors.forename: Shuang-shuang
authors.initials: SS
authors.lastname: Shao
authors.affiliation: The Key Laboratory of Biochemical Utilization of Zhejiang Province, Zhejiang Forestry Academy, Hangzhou 310023, China. Electronic address: kite006@126.com.
authors.forename: Liang
authors.initials: L
authors.lastname: He
authors.affiliation: The Key Laboratory of Biochemical Utilization of Zhejiang Province, Zhejiang Forestry Academy, Hangzhou 310023, China.
authors.forename: Junwen
authors.initials: J
authors.lastname: Cheng
authors.affiliation: The Key Laboratory of Biochemical Utilization of Zhejiang Province, Zhejiang Forestry Academy, Hangzhou 310023, China.
authors.forename: Sufang
authors.initials: S
authors.lastname: Han
authors.affiliation: Institute of Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou 310058, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Liu
mesh_terms: D002236:Carbohydrate Conformation; D062610:Fungal Polysaccharides / Q000737:chemistry*; D025282:Mycelium / Q000737:chemistry; D010143:Paecilomyces / Q000737:chemistry*
chemical_list: D062610:Fungal Polysaccharides
keywords: AFM; Chain conformation; Heteropolysaccharide; Paecilomyces cicadae; Structural characterization