Selected cell wall proteins from Zea mays: Assessment of their role in wall hydrolysis

Abstract

Coleoptile cell wall proteins from Zea mays L. hybrid B 37 × Mo 17 were extracted and fractionated. Three enzymes identified in that extract were examined to determine their role in cell wall hydrolysis with a goal of evaluating the extent to which they participated in autohydrolytic reactions. Two separate proteins were identified as endo‐ and exo‐glucanases. Incubation of these enzymes with heat inactivated cell walls, liberates products derived from the constitutive (1→3), (1→4)‐β‐d‐glucan. The release of sugars from walls resembles that of cell wall autolysis. A third cell wall protein degraded polysaccharides in a more general manner, releasing carbohydrates containing xylose, arabinose, galactose and glucose. Polyclonal antibodies raised against the exoglucanase protein suppressed autolytic reactions of isolated cell wall.