Structural highlights
5l8r is a 16 chain structure with sequence from Pisum sativum. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
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| Ligands: | , , , , , , , , , , , , , |
| Related: | 4y28, 1jb0, 4xk8 |
| Activity: | Photosystem I, with EC number 1.97.1.12 |
| Resources: | FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT |
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Function
[PSAC_PEA] Apoprotein for the two 4Fe-4S centers FA and FB of photosystem I (PSI); essential for photochemical activity. FB is the terminal electron acceptor of PSI, donating electrons to ferredoxin. The C-terminus interacts with PsaA/B/D and helps assemble the protein into the PSI complex. Required for binding of PsaD and PsaE to PSI. PSI is a plastocyanin-ferredoxin oxidoreductase, converting photonic excitation into a charge separation, which transfers an electron from the donor P700 chlorophyll pair to the spectroscopically characterized acceptors A0, A1, FX, FA and FB in turn (By similarity).[HAMAP-Rule:MF_01303] [PSAI_PEA] May help in the organization of the PsaL subunit. [A0A0F6NGI2_PEA] PsaA and PsaB bind P700, the primary electron donor of photosystem I (PSI), as well as the electron acceptors A0, A1 and FX. PSI is a plastocyanin-ferredoxin oxidoreductase, converting photonic excitation into a charge separation, which transfers an electron from the donor P700 chlorophyll pair to the spectroscopically characterized acceptors A0, A1, FX, FA and FB in turn. Oxidized P700 is reduced on the lumenal side of the thylakoid membrane by plastocyanin.[HAMAP-Rule:MF_00482] [CB23_PEA] The light-harvesting complex (LHC) functions as a light receptor, it captures and delivers excitation energy to photosystems with which it is closely associated.[1] May channel protons produced in the catalytic Mn center of water oxidation into the thylakoid lumen.[2] [D5MAL3_PEA] May help in the organization of the PsaE and PsaF subunits.[HAMAP-Rule:MF_00522] [CB24_PEA] The light-harvesting complex (LHC) functions as a light receptor, it captures and delivers excitation energy to photosystems with which it is closely associated.[3] May channel protons produced in the catalytic Mn center of water oxidation into the thylakoid lumen.[4] [PSAA_PEA] PsaA and PsaB bind P700, the primary electron donor of photosystem I (PSI), as well as the electron acceptors A0, A1 and FX. PSI is a plastocyanin-ferredoxin oxidoreductase, converting photonic excitation into a charge separation, which transfers an electron from the donor P700 chlorophyll pair to the spectroscopically characterized acceptors A0, A1, FX, FA and FB in turn. Oxidized P700 is reduced on the lumenal side of the thylakoid membrane by plastocyanin.
Publication Abstract from PubMed
Four elaborate membrane complexes carry out the light reaction of oxygenic photosynthesis. Photosystem I (PSI) is one of two large reaction centres responsible for converting light photons into the chemical energy needed to sustain life. In the thylakoid membranes of plants, PSI is found together with its integral light-harvesting antenna, light-harvesting complex I (LHCI), in a membrane supercomplex containing hundreds of light-harvesting pigments. Here, we report the crystal structure of plant PSI-LHCI at 2.6 A resolution. The structure reveals the configuration of PsaK, a core subunit important for state transitions in plants, a conserved network of water molecules surrounding the electron transfer centres and an elaborate structure of lipids bridging PSI and its LHCI antenna. We discuss the implications of the structure for energy transfer and the evolution of PSI.
Structure of the plant photosystem I supercomplex at 2.6 A resolution.,Mazor Y, Borovikova A, Caspy I, Nelson N Nat Plants. 2017 Mar 1;3:17014. doi: 10.1038/nplants.2017.14. PMID:28248295[5]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Jahns P, Junge W. Dicyclohexylcarbodiimide-binding proteins related to the short circuit of the proton-pumping activity of photosystem II. Identified as light-harvesting chlorophyll-a/b-binding proteins. Eur J Biochem. 1990 Nov 13;193(3):731-6. PMID:2174365
- ↑ Jahns P, Junge W. Dicyclohexylcarbodiimide-binding proteins related to the short circuit of the proton-pumping activity of photosystem II. Identified as light-harvesting chlorophyll-a/b-binding proteins. Eur J Biochem. 1990 Nov 13;193(3):731-6. PMID:2174365
- ↑ Jahns P, Junge W. Dicyclohexylcarbodiimide-binding proteins related to the short circuit of the proton-pumping activity of photosystem II. Identified as light-harvesting chlorophyll-a/b-binding proteins. Eur J Biochem. 1990 Nov 13;193(3):731-6. PMID:2174365
- ↑ Jahns P, Junge W. Dicyclohexylcarbodiimide-binding proteins related to the short circuit of the proton-pumping activity of photosystem II. Identified as light-harvesting chlorophyll-a/b-binding proteins. Eur J Biochem. 1990 Nov 13;193(3):731-6. PMID:2174365
- ↑ Mazor Y, Borovikova A, Caspy I, Nelson N. Structure of the plant photosystem I supercomplex at 2.6 A resolution. Nat Plants. 2017 Mar 1;3:17014. doi: 10.1038/nplants.2017.14. PMID:28248295 doi:http://dx.doi.org/10.1038/nplants.2017.14
