Location of a Protease and its Inhibitor in the Barley Kernel

Tissues of barley caryopsis and seedling were examined for the protease, BAPAase, and an inhibitor. The enzyme was present in extracts of alevn‐one but was absent from aleurone incubation media and extracts of: embryo with scutellum; seedling with scutellum and rootlets, and endosperm that was free of aleurone tissue. The enzyme was present in non‐incubated aleurone and did not increase significantly during incubation under conditions where alpha‐amylase increased in the medium and tissue. Addition of gibberellie acid produced no detectable increase in BAPAase. Extracts of endosperm had weak BAPAase‐inhibitory activity; embryo or seedling extracts produced strong inhibition. The inhibitor present in these extracts was dialyzable.