Profiiles of Proteins in Guard-cell and Mesophyll Protoplasts from Vicia faba L. Fractionated by Sodium Dodecylsulfate-Polyacrylamide Gel Electrophoresis

Polypeptides of low molecular weight unique to protoplasts ofVicia guard cells were found by sodium dodecylsulfate-polyacrylamidegel electrophoresis. The polypeptides were 16 kDa (2 species),15 kDa and 12.5 kDa, and were concentrated in membrane-richfractions. The large subunit and holoenzyme of ribulose bisphosphatecarboxylase were identified in guard-cell protoplasts by immunoblotting. ³Present address: Biological Laboratory, College of GeneralEducation, Kyushu University, Ropponmatsu, Fukuoka, 810 Japan. (Received January 25, 1989; Accepted April 24, 1989)