[Purification and activities of an alkaline protein from mushroom Coprinus comatus]

An Alkaline protein, y3, can be purified from the fruiting bodies of mushroom Coprinus comatus by means of CM-sepharose FF ion-exchange column chromatography and Superdex 75 High Resolution molecular sieve chromatography. The protein has a molecular weight of about 14.4kD by SDS-PAGA. Some activities of y3 have been detected, and the result is the following: the inhibition rate against Tobacco Mosaic Virus is 83.0% when the concentration of y3 is 12.5 microg/ mL. y3 is able to agglutinate rabbit and human erythrocytes at the concentration of 1.562 microg/mL and 0.781 microg/mL. Using an assay system based on mach cancer cell line MGC-803, y3 was studied for its inhibitory ability against celles multiplication, and the IC50 is 12 microg/mL. The N-terminal sequence is NRDVAACARFIDDFCDTLTP, which has no homology with other sequences in Genbank.