Premium
Unassembled subunits of the photosynthetic oxygen‐evolving complex present in the thylakoid lumen are long‐lived and assembly‐competent
Author(s) -
Akiko Hashimoto,
Yasusi Yamamoto,
Theg Steven M.
Publication year - 1996
Publication title -
febs letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.593
H-Index - 257
eISSN - 1873-3468
pISSN - 0014-5793
DOI - 10.1016/0014-5793(96)00686-2
Subject(s) - thylakoid , protein subunit , photosystem ii , chloroplast , cytochrome b6f complex , photosynthesis , biophysics , biology , photosystem i , oxygen evolution , photosynthetic reaction centre , biochemistry , chemistry , microbiology and biotechnology , gene , electrode , electrochemistry
Physiologically healthy pea chloroplasts contain unassembled, soluble subunits of the oxygen‐evolving complex in the thylakoid lumen. We report that the lifetimes of two of these subunits, both on and off the membrane, exceed 8 h in vitro. We also demonstrate that each of the subunits present in the thylakoid lumen is competent for assembly into the membrane‐bound complex. These data are consistent with the postulate that the soluble lumen‐resident subunits play a role in photosystem II homeostasis. We also demonstrate that the reconstitution of the 33 kDa subunit is inhibited by extremely low concentrations of Triton X‐100, suggesting that hydrophobic interactions are involved in the binding of this subunit to the photosystem II reaction center.