Alpha-1,4-glucan lyase, a new class of starch/glycogen-degrading enzyme. II. Subcellular localization and partial amino-acid sequence.

Antibodies have been raised against an alpha-1,4-glucan lyase purified from the red alga Gracilariopsis lemaneiformis (Bory) Dawson, Acleto et Foldvik. Localization of alpha-1,4-glucan lyase in ultra-thin sections of the red alga was performed using immunogold/transmission electron microscopy. The enzyme was found exclusively in the stroma of the chloroplasts of the algal cells, not in the cell wall, cytosol or around the cytosolic starch granules. Partial amino-acid sequences of the algal lyase, with a total length of 100 amino-acid residues, were obtained. No sequence homology was found with proteins and peptides of known sequences.