1C51

PHOTOSYNTHETIC REACTION CENTER AND CORE ANTENNA SYSTEM (TRIMERIC), ALPHA CARBON ONLY

Summary for 1C51

• Entry DOI: 10.2210/pdb1c51/pdb
• Descriptor: PROTEIN (PHOTOSYSTEM I: SUBUNIT PSAA), PHYLLOQUINONE, IRON/SULFUR CLUSTER, ... (11 entities in total)
• Functional Keywords: photosynthesis, photosynthetic reaction center, oxygenic photosynthesis, core- antenna light-harvesting system, thermophilic cyanobacterium, helix-bundle membrane protein, photosynthesis-electron transport complex, photosynthesis/electron transport
• Biological source: Synechococcus elongatus; More
• Total number of polymer chains: 8
• Total formula weight: 223365.34

Authors

Klukas, O.,Schubert, W.D.,Jordan, P.,Krauss, N.,Fromme, P.,Witt, H.T.,Saenger, W. (deposition date: 1999-10-21, release date: 2000-03-31, Last modification date: 2023-12-27)

Primary citation

Klukas, O.,Schubert, W.D.,Jordan, P.,Krauss, N.,Fromme, P.,Witt, H.T.,Saenger, W.
Photosystem I, an improved model of the stromal subunits PsaC, PsaD, and PsaE.
J.Biol.Chem., 274:7351-7360, 1999

PubMed Abstract: An improved electron density map of photosystem I (PSI) calculated at 4-A resolution yields a more detailed structural model of the stromal subunits PsaC, PsaD, and PsaE than previously reported. The NMR structure of the subunit PsaE of PSI from Synechococcus sp. PCC7002 (Falzone, C. J., Kao, Y.-H., Zhao, J., Bryant, D. A., and Lecomte, J. T. J. (1994) Biochemistry 33, 6052-6062) has been used as a model to interpret the region of the electron density map corresponding to this subunit. The spatial orientation with respect to other subunits is described as well as the possible interactions between the stromal subunits. A first model of PsaD consisting of a four-stranded beta-sheet and an alpha-helix is suggested, indicating that this subunit partly shields PsaC from the stromal side. In addition to the improvements on the stromal subunits, the structural model of the membrane-integral region of PSI is also extended. The current electron density map allows the identification of the N and C termini of the subunits PsaA and PsaB. The 11-transmembrane alpha-helices of these subunits can now be assigned uniquely to the hydrophobic segments identified by hydrophobicity analyses.

PubMed: 10066799
DOI: 10.1074/jbc.274.11.7351

Experimental method

X-RAY DIFFRACTION (4 Å)