Geetha V, Gnanam A
Biochim Biophys Acta. 1980 Jul 29;608(2):427-34. doi: 10.1016/0005-2787(80)90188-4.
Isolated chloroplasts from the seedlings of Sorghum vulgare leaves incorporated 14C-labelled amino acids into soluble and membrane-bound products, using light as the sole energy source. The labelled chloroplasts were lysed osmotically and fractionated on a discontinuous gradient of sucrose into the soluble, thylakoid and envelope membrane fractions. About 24% of the total radioactivity in the chloroplasts was recovered in the soluble fraction, 66% in the thylakoid membranes and less than 1% in the envelope membranes. The products of protein synthesis in the different fractions, as well as in the whole chloroplasts were analyzed by electrophoresis on polyacrylamide gels in the presence of sodium dodecyl sulfate. There were three zones of radioactivity in the gels of the soluble fraction. The thylakoid membranes contained nine labelled polypeptides, the most prominent ones having the molecular weights of about 66 000, 56 000 and 27 000. The envelope membranes contained a major radioactive component of molecular weight of about 54 000 and two other minor components.
从高粱叶片幼苗中分离出的叶绿体，以光作为唯一能源，将14C标记的氨基酸掺入可溶性和膜结合产物中。标记的叶绿体经渗透压裂解，然后在不连续的蔗糖梯度上进行分级分离，得到可溶性部分、类囊体和包膜膜部分。叶绿体中约24%的总放射性在可溶性部分中回收，66%在类囊体膜中，而在包膜膜中的不到1%。通过在十二烷基硫酸钠存在下的聚丙烯酰胺凝胶电泳分析不同部分以及整个叶绿体中蛋白质合成的产物。可溶性部分的凝胶中有三个放射性区域。类囊体膜含有九种标记多肽，最突出的多肽分子量约为66000、56000和27000。包膜膜含有一种分子量约为54000的主要放射性成分和另外两种次要成分。
