Pigment stoichiometry of a newly isolated D1—D2—Cyt b 559 complex from the higher plant Beta vulgaris L

FEBS Letters

Yruela, I.¹  Montoya, G.¹  Picorel, R.¹ 

[1] Estación Experimental Aula Dei, CSIC Apdo. 202, 50080 Zaragoza, Spain

关键词: Beta vulgaris;    Photosystem II;    Pigment;    Reaction center;    Stoichiometry;   

DOI  :  10.1016/0014-5793(91)80601-X

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Two D1-D2-Cyt b ₅₅₉ complexes with different pigment stoichiometry were isolated from the higher plant B. vulgaris. The procedures for isolating both complexes only differed in the washing time of the DEAE column with 50 mM Tris-HCl, pH 7.2, 0.05% Triton X-100 and 30 mM NaCl. When the column was washed until the eluate had an absorbance of 0.01 at 670 nm, the isolated D1—D2—Cyt b ₅₅₉ complex presented a pigment stoichiometry of 6 chlorophyll a, 2 β-carotene, and 1 cytochrome b ₅₅₉ per 2 pheophytin a. In contrast, when the column was exhaustively washed until the eluate reached an absorbance of 0.005 at 670 nm, the complex had a stoichiometry of 4 chlorophyll a, 1 β-carotene, and 1 cytochrome b ₅₅₉ per 2 pheophytin a. We think that the former stoichiometry corresponds to that of the native D1—D2—Cyt b ₅₅₉ complex. Moreover, both preparations showed 2 mol of pheophytin a per 1 mol of reaction center protein.

【 授权许可】

Unknown