Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Presence in photosystem II core complexes of a 34-kilodalton polypeptide required for water photolysis

Journal Article · · Plant Physiol.; (United States)
DOI:https://doi.org/10.1104/pp.76.3.829· OSTI ID:5934809
Photosystem II (PSII) reaction center core complexes have been isolated and characterized from wild type (WT) Scenedesmus obliquus and from its LF-1 mutant. LF-1 thylakoids are blocked on the oxidizing side of PSII and have a reduced Mn content. Visible absorption and low temperature fluorescence spectra of both core complexes are identical and resemble those reported for spinach. Lithium dodecyl sulfate-polycrylamide gel electrophoresis reveals that a protein alteration, originally observed in thylakoid membranes is retained in the PSII core particles. That is, a 34-kilodalton (kD) polypeptide, present in the WT core complex, is missing in the mutant, and the core complex of the mutant contains a 36-kD protein not present in the WT. The 34-kD intrinsic protein is also observed in O/sub 2/-evolving PSII preparations and PSII core complexes from spinach. It is distinct from the 33-kD extrinsic protein first reported by T. Kuwabara and N. Murata. We suggest that the 34-kD protein is a site of Mn binding in the PSII membrane. 21 references, 3 figures.
Research Organization:
Solar Energy Research Inst., Golden, CO
DOE Contract Number:
AC02-83CH10093
OSTI ID:
5934809
Journal Information:
Plant Physiol.; (United States), Journal Name: Plant Physiol.; (United States) Vol. 76:3; ISSN PLPHA
Country of Publication:
United States
Language:
English