Southern Regional Research Laboratory, New Orleans, Louisiana 70179.
Plant Physiol. 1972 Jun;49(6):937-43. doi: 10.1104/pp.49.6.937.
Spherosomes are bounded by unusual single-line "membranes" which measure 2 to 3.5 nanometers in width, contrasted to the well known tripartite unit-membranes which measure 6 to 8.5 nanometers in over-all thickness. Juxtaposed externally (from the side addressing the hyaloplasm), two spherosomal membranes adjoin to form a thicker single line, but apposed internally (the sides that contact stored lipid) two single-line membranes touch to form a tripartite structure resembling a unit-membrane. Morphologically, we interpret the single-line membranes of spherosomes as half unit-membranes whose polar surfaces face the hyaloplasm and whose lipoidal nonpolar surfaces contact internal storage lipid.Corroboration of this interpretation was shown biochemically by demonstrating the presence of membrane structural protein in peanut spherosomes. In addition, an immunological identity between membrane protein isolated from spherosomes of quiescent seeds and membrane protein extracted from the mitochondrial fraction of 10-day germinated seedlings was observed. We conclude that the atypical, single-line membranes bounding spherosomes are in fact biological membranes that correspond to half unit-membranes.
球状体被不寻常的单线“膜”所包围，其宽度为 2 至 3.5 纳米，与众所周知的三部分单位膜相比，其总厚度为 6 至 8.5 纳米。从外部（从面向透明质体的侧面）并列的两个球状体膜连接形成更厚的单线，但从内部（与储存脂质接触的侧面）并列的两个单线膜接触形成类似于单位膜的三部分结构。从形态学上看，我们将球状体的单线膜解释为半单位膜，其极性表面面向透明质体，而亲脂性非极性表面与内部储存脂质接触。通过证明花生球状体中存在膜结构蛋白，从生物化学上证实了这一解释。此外，从休眠种子的球状体中分离出的膜蛋白与从 10 天发芽幼苗的线粒体部分提取的膜蛋白之间观察到免疫同一性。我们得出结论，包围球状体的非典型单线膜实际上是生物膜，对应于半单位膜。
