Andrews T J, Greenwood D M, Yellowlees D
Arch Biochem Biophys. 1984 Oct;234(1):313-7. doi: 10.1016/0003-9861(84)90354-0.
Ribulose bisphosphate carboxylase from the procaryotic green alga, Prochloron (the symbiont of Lissoclinum patellum), has eight large and eight small subunits, and a low affinity for CO2, similar to that of cyanobacterial carboxylases. The small subunits were progressively removed from this carboxylase and from that from the cyanobacterium, Synechococcus ACMM 323, by twice-repeated, mild-acid precipitation. This procedure produced large-subunit octamers, greatly depleted in small subunits, as well as isolated small subunits. Catalytic activity of the large-subunit preparations reflected their residual small-subunit content. The two large-subunit preparations were reconstituted with both homologous and heterologous small subunits. The reassembled enzymes were catalytically competent in all cases. When fully saturated with small subunits, the hybrid enzymes were only about 20% less active than the homologously reconstituted enzymes. Heterologous reconstitution underscores the essential function of the small subunits in catalysis.
来自原核绿藻原绿球藻（帕氏扁海鞘的共生体）的核酮糖二磷酸羧化酶有八个大亚基和八个小亚基，对二氧化碳的亲和力较低，这与蓝藻羧化酶类似。通过两次重复的温和酸沉淀法，从小球藻属的该羧化酶以及蓝细菌聚球藻ACMM 323的羧化酶中逐步去除小亚基。此过程产生了小亚基严重缺失的大亚基八聚体以及分离出的小亚基。大亚基制剂的催化活性反映了其残留的小亚基含量。用同源和异源小亚基对两种大亚基制剂进行了重组。在所有情况下，重新组装的酶都具有催化活性。当小亚基完全饱和时，杂合酶的活性仅比同源重组酶低约20%。异源重组强调了小亚基在催化中的基本功能。
