1 , 2 - i - D - Mannosidase from Peniciiium citrinum : molecular and enzymic properties of two isoenzymes
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چکیده
Two isoforms of acidic 1,2-a-D-mannosidases have been isolated from culture filtrate of Penicillium citrinum. The pl values of the two forms, designated 1,2-a-mannosidase la and lb, were 4.6 and 4.7 respectively. Isoenzymes Ia and Ib exhibited the same molecular mass which was determined to be 53 kDa by SDS/ PAGE and 54 kDa by gel-permeation chromatography. Enzymes Ia and lb hydrolysed yeast mannan and 1,2-a-linked mannooligosaccharides, but did not hydrolyse p-nitrophenyl a-D-man-
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