One proteoglycan from the fruiting bodies of Chroogomphis rutilus (Schaeff.: Fr.) O.K. Miller: purification and structural features

A water-soluble proteoglycan (CRP-W2) was purified from the fruiting bodies of Chroogomphis rutilus by boiled water extraction, ethanol precipitation, weak anion exchange and size exclusion chromatography. Its molecular weight (Mw) was estimated to be about 1.3 × 104 Da using high-performance size-exclusion chromatography (HPSEC). As a precondition to understand the bioactivity, the structural features of CRP-W2 was analyzed using chemical methods, IR spectroscopy and NMR spectroscopy. The results indicated that CRP-W2 had a backbone consisting of 1,6-linked and 1,2,6-linked-α-d-Gal, which was terminated with 1-linked-α-d-Man and 1-linked-α-d-Glc residues at the O-2 position of 1,2,6-linked-α-d-Gal in the molar ratio of 2:2:1:1.