Bölter B, May T, Soll J
Botanisches Institut, Universität Kiel, Germany.
FEBS Lett. 1998 Dec 11;441(1):59-62. doi: 10.1016/s0014-5793(98)01525-7.
The protein import complex of the chloroplastic outer envelope (Toc-complex) contains a prominent subunit of 86 kDa molecular weight (Toc86). Toc86 was identified as a putative precursor receptor. The Arabidopsis genome sequencing project indicates that Toc86 represents only a proteolytic fragment of a larger polypeptide of 160 kDa. The 160-kDa protein, which we name Toc160, is only present in significant amounts in pea chloroplasts isolated under stringent conditions. The capacity of chloroplasts to import an in vitro translated precursor protein correlates well with the integrity of Toc160. We conclude that Toc160 is still a bonafide subunit of the protein import machinery of chloroplasts.
叶绿体外被膜的蛋白质输入复合体（Toc复合体）包含一个分子量为86 kDa的主要亚基（Toc86）。Toc86被鉴定为一种假定的前体受体。拟南芥基因组测序项目表明，Toc86只是一个160 kDa较大多肽的蛋白水解片段。我们将这种160 kDa的蛋白质命名为Toc160，它仅在严格条件下分离得到的豌豆叶绿体中大量存在。叶绿体导入体外翻译前体蛋白的能力与Toc160的完整性密切相关。我们得出结论，Toc160仍然是叶绿体蛋白质输入机制的一个真正亚基。
