Isolation of a 41-kDa protein with cell adhesion activity for animal tumorcells from the mushroom Hypsizigus marmoreus by affinity chromatography with type IV collagen immobilized on agarose

A type IV collagen-binding protein of 41 kDa was isolated from the mushroom Hypsizigus marmoreus and the protein was designated as HM41. The Western b lotting analysis with anti-HM41 antibodies demonstrated that HM41 was unrel ated to HM23, which had been shown to have an affinity for type IV collagen . The microsequence analysis of the membrane-blotted peptides generated by fragmentation with cyanogen bromide showed no homologous proteins reported. HM41 had cell adhesion-promoting activity for murine Lewis lung carcinoma LL2 cells and human fibrosarcoma HT1080 cells. These results indicate that HM41 is a hitherto undescribed fungus protein that can interact both with a nimal extracellular matrix protein type IV collagen and with animal tumor c ells.