Presence de sous-unites de la RubPcase dan les enveloppes des chloroplastes d'epinard

Abstract

Electrophoretic analysis of the envelope of Spinach chloroplasts demonstrated the presence of two polypeptides with apparent molecular weight similar to that of the subunits of the ribulose-1,5-biphosphate-carboxylase (RubPcase). The identification of the small and large subunits of RubPcase, in the envelope fraction, was further established with serum anti-RubPcase. These molecules do not seem in relation with a stromatic contamination which could occur during the course of the envelopes preparation. Their presence could reflect an ‘in vivo’ binding with the chloroplastic envelope and perhaps a transient stage in the process of the transfer of the RubPcase small subunit into the chloroplast.