Williams J C, Steiner L A, Feher G, Simon M I
Proc Natl Acad Sci U S A. 1984 Dec;81(23):7303-7. doi: 10.1073/pnas.81.23.7303.
The reaction center is an integral membrane protein that, together with several cofactors, mediates the primary photochemical events in bacterial photosynthesis. The amino-terminal sequences of the three subunits, L, M, and H, of the reaction center protein and the sequence of the structural gene encoding the M subunit have been reported previously. In the present study, we found that the 3' end of the structural gene encoding the L subunit overlaps by eight bases the 5' end of the gene encoding the M subunit. The primary structure of the L subunit has been determined from the nucleotide sequence of the gene and from analyses of the amino and carboxyl termini of the protein. The sequences of a number of tryptic and chymotryptic peptides were used to corroborate the nucleotide sequence. The L subunit was found to be composed of 281 amino acids (Mr 31,319) and to contain five hydrophobic segments. It is homologous to the M subunit and to a plant thylakoid protein referred to as the QB or Mr 32,000 protein.
反应中心是一种整合膜蛋白，它与几种辅因子一起介导细菌光合作用中的初级光化学事件。反应中心蛋白的三个亚基L、M和H的氨基末端序列以及编码M亚基的结构基因的序列先前已有报道。在本研究中，我们发现编码L亚基的结构基因的3'末端与编码M亚基的基因的5'末端有8个碱基重叠。L亚基的一级结构已根据该基因的核苷酸序列以及对该蛋白质的氨基和羧基末端的分析确定。一些胰蛋白酶和胰凝乳蛋白酶肽段的序列用于证实核苷酸序列。发现L亚基由281个氨基酸组成（Mr 31,319），并包含五个疏水片段。它与M亚基以及一种称为QB或Mr 32,000蛋白的植物类囊体蛋白同源。
