Lemaire C, Wollman F A
Service de Photosynthèse, Institut de Biologie Physico-chimique, Paris, France.
J Biol Chem. 1989 Jun 15;264(17):10228-34.
We have characterized the subunit composition of the chloroplast ATP synthase from Chlamydomonas reinhardtii by means of a comparison of the polypeptide deficiencies in a mutant defective in photophosphorylation, with the polypeptide content in purified coupling factor (CF)1 and CF1.CF0 complexes. We could distinguish nine subunits in the enzyme, four of which were CF0 subunits. Further characterization of these subunits was undertaken by immunoblotting experiments, [14C]dicyclohexylcarbodiimide binding and analysis of their site of translation. In particular, we were able to show the presence of an as yet unidentified delta subunit in CF1 from C. reinhardtii. We have identified a 70-kDa peripheral membrane protein in the thylakoid membranes of C. reinhardtii, which is immunologically related to the beta subunit of CF1. We discuss its conceivable ATPase function with respect to the Ca2+-dependent ATPase activity previously reported in the thylakoid membranes from C. reinhardtii.
我们通过比较光合磷酸化缺陷型突变体中的多肽缺陷与纯化的偶联因子（CF）1和CF1·CF0复合物中的多肽含量，对莱茵衣藻叶绿体ATP合酶的亚基组成进行了表征。我们能够在该酶中区分出9个亚基，其中4个是CF0亚基。通过免疫印迹实验、[14C]二环己基碳二亚胺结合以及对其翻译位点的分析，对这些亚基进行了进一步表征。特别是，我们能够证明莱茵衣藻的CF1中存在一个尚未鉴定的δ亚基。我们在莱茵衣藻的类囊体膜中鉴定出一种70 kDa的外周膜蛋白，它与CF1的β亚基具有免疫相关性。我们根据先前报道的莱茵衣藻类囊体膜中Ca2+依赖性ATP酶活性，讨论了其可能的ATP酶功能。
