The pea chloroplast membrane‐associated protein, IEP96, is a subunit of acetyl‐CoA carboxylase

摘要: Two forms of acetyl-CoA carboxylase (ACCase) have been characterized in pea (Pisum sativum L.) leaves; a heteromeric chloroplast enzyme and homomeric, presumably cytosolic enzyme. The biotin (BC), carboxyl carrier protein (BCCP), beta-carboxyltransferase (CT) subunits the plastidial-ACCase recently cloned. To further characterize carboxyltransferase, an improved assay for CT was developed used to follow its partial purification. activity co-purifies with ACCase during gel permeation chromatography. However, upon anion-exchange chromatography or native PAGE, separates from BC BCCP is lost. In addition, it demonstrated that previously sequenced cDNA unknown function (IEP96) predicted molecular weight 91 kDa encodes alpha-CT subunit MS-ACCase. Antibodies raised against first 404 amino acids IEP96 detected polypeptide co-eluted plastidial activities. These antibodies also immunoprecipitated activities both concomitant precipitation beta-CT subunit. Furthermore, protein. Two-dimensional PAGE DEAE purification tight association Pea leaf fractionated into soluble membrane fractions primarily associated fraction. Together, these data demonstrate ACCase.