Haley J, Bogorad L
Department of Cellular and Developmental Biology, Harvard University, Cambridge, MA 02138.
Proc Natl Acad Sci U S A. 1989 Mar;86(5):1534-8. doi: 10.1073/pnas.86.5.1534.
Four polypeptides, three of which are chloroplast-encoded, have been shown to be associated with the thylakoid membrane cytochrome b6-f complex. In this report, the gene for a fifth polypeptide, which copurifies with the b6-f complex, is identified through the use of an antibody generated against a synthetic decapeptide predicted from a maize chloroplast DNA sequence. The deduced 37-amino acid sequence of the immunoreactive 4-kDa polypeptide is 100% and 86% conserved in the respective similar open reading frames encoded by Nicotiana tabacum and Marchantia chloroplast DNA. The 4-kDa polypeptide is present in both etioplasts and chloroplasts of maize and is found as well in spinach, tobacco, pea, wheat, and rice thylakoids. Similar to the other subunits of the b6-f complex, it is intrinsic to the membrane, and its hydrophilic COOH terminus is located at the stromal thylakoid surface. We propose to call the 4-kDa polypeptide "subunit 5" and the chloroplast gene that encodes it the petE gene.
已证实有四种多肽与类囊体膜细胞色素b6-f复合体相关联，其中三种由叶绿体编码。在本报告中，通过使用针对根据玉米叶绿体DNA序列预测的合成十肽产生的抗体，鉴定出了与b6-f复合体共纯化的第五种多肽的基因。免疫反应性4 kDa多肽推导的37个氨基酸序列在烟草和地钱叶绿体DNA编码的各自相似开放阅读框中分别有100%和86%的保守性。4 kDa多肽存在于玉米的黄化质体和叶绿体中，也存在于菠菜、烟草、豌豆、小麦和水稻的类囊体中。与b6-f复合体的其他亚基相似，它是膜内在蛋白，其亲水的COOH末端位于类囊体基质表面。我们提议将4 kDa多肽称为“亚基5”，并将编码它的叶绿体基因称为petE基因。
