Wada A, Koyama K, Maki Y, Shimoi Y, Tanaka A, Tsuji H
Department of Physics, Faculty of Science, Kyoto University, Japan.
FEBS Lett. 1993 Mar 15;319(1-2):115-8. doi: 10.1016/0014-5793(93)80048-y.
The proteins of the 30 S ribosomal subunits from spinach chloroplasts were investigated using a radical-free and highly reducing (RFHR) method of two-dimensional polyacrylamide gel electrophoresis (PAGE). Twenty-three proteins were resolved on the gel down to the smallest protein of 5 kDa. The N-terminal amino acid sequence of the 5 kDa protein showed no homology with that of any other protein stored in databases, and the copy numbers were estimated to be 0.88 +/- 0.16 and 0.72 +/- 0.04 in the 30 S subunits and the 70 S ribosomes, respectively. The results suggest that the 5 kDa protein, which we have called SCS23, may be an essential ribosomal protein specific to spinach chloroplasts.
采用无自由基且强还原(RFHR)的二维聚丙烯酰胺凝胶电泳(PAGE)方法,对菠菜叶绿体30 S核糖体亚基的蛋白质进行了研究。凝胶上分辨出了23种蛋白质,最小的蛋白质为5 kDa。5 kDa蛋白质的N端氨基酸序列与数据库中存储的任何其他蛋白质均无同源性,其拷贝数在30 S亚基和70 S核糖体中分别估计为0.88±0.16和0.72±0.04。结果表明,我们命名为SCS23的5 kDa蛋白质可能是菠菜叶绿体特有的一种必需核糖体蛋白。