Purification and Properties of an alpha-L-Arabinofuranosidase from Cotyledons of Soybean Seedlings.

Abstract

An α-L-arabinosidase (α-L-arabinofuranoside arabinofuranohydrolase, EC 3.2.1.55) that can degrade both purified water soluble polysaccharide from soybean seeds and p-nitrophenyl-α-L-arabinofuranoside was purified 453-fold to near homogeneity from cotyledons of 4-day-old soybean seedlings. The optimum pH and Km against p-nitrophenyl-α-L-arabinofuranoside of the purified enzyme were 4.8 and 0.53 mM, respectively. The enzyme was activated by Ca2+ and Zn2+ ions, but Cu2+, Hg2+, EDTA, and L-arabonic-γ-lactone inhibited the enzyme activity. The molecular weight of the enzyme subunit was estimated to be 87, 000 by SDS-PAGE.