Purification and Some Properties of Two Phosphorylases from Typha latifolia Pollen

Abstract

Two starch phosphorylases, P-1 and P-2, were purified from pollen grains of Typha latifolia Linne. The purified P-1 was homogeneous on polyacrylamide gel electrophoresis and its molecular weight was 112,000 by SDS-polyacrylamide gel electrophoresis. Both enzymes had optimum pHs of 5.5 ~ 5.8 in the direction of Pi release and of 7.3 ~ 8.0 in the direction of G-I-P formation. In both directions, the two enzymes had similar activities for soluble starch and amylose, but a definite difference of activity for starch granules from the pollen was observed; P-1 showed a high activity, comparable to those for other substrates, while the activity of P-2 was very low in the direction of Pi release. P-1 had higher Km values for amylose, maltoheptaose, and maltopentaose in both directions than P-2 did.