1yf6: Difference between revisions
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[[Image:1yf6.gif|left|200px]] | [[Image:1yf6.gif|left|200px]] | ||
'''Structure of a quintuple mutant of photosynthetic reaction center from rhodobacter sphaeroides''' | {{Structure | ||
|PDB= 1yf6 |SIZE=350|CAPTION= <scene name='initialview01'>1yf6</scene>, resolution 2.25Å | |||
|SITE= | |||
|LIGAND= <scene name='pdbligand=FE2:FE+(II)+ION'>FE2</scene>, <scene name='pdbligand=CL:CHLORIDE+ION'>CL</scene>, <scene name='pdbligand=PO4:PHOSPHATE+ION'>PO4</scene>, <scene name='pdbligand=BCL:BACTERIOCHLOROPHYLL+A'>BCL</scene>, <scene name='pdbligand=BPH:BACTERIOPHEOPHYTIN+A'>BPH</scene>, <scene name='pdbligand=U10:UBIQUINONE-10'>U10</scene>, <scene name='pdbligand=SPO:SPHEROIDENE'>SPO</scene>, <scene name='pdbligand=CDL:CARDIOLIPIN'>CDL</scene>, <scene name='pdbligand=HTO:HEPTANE-1,2,3-TRIOL'>HTO</scene>, <scene name='pdbligand=LDA:LAURYL+DIMETHYLAMINE-N-OXIDE'>LDA</scene> and <scene name='pdbligand=GOL:GLYCEROL'>GOL</scene> | |||
|ACTIVITY= | |||
|GENE= pufL ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=1063 Rhodobacter sphaeroides]), pufM ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=1063 Rhodobacter sphaeroides]), puhA ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=1063 Rhodobacter sphaeroides]) | |||
}} | |||
'''Structure of a quintuple mutant of photosynthetic reaction center from rhodobacter sphaeroides''' | |||
==Overview== | ==Overview== | ||
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==About this Structure== | ==About this Structure== | ||
1YF6 is a [ | 1YF6 is a [[Protein complex]] structure of sequences from [http://en.wikipedia.org/wiki/Rhodobacter_sphaeroides Rhodobacter sphaeroides]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1YF6 OCA]. | ||
==Reference== | ==Reference== | ||
Quinone (QB) reduction by B-branch electron transfer in mutant bacterial reaction centers from Rhodobacter sphaeroides: quantum efficiency and X-ray structure., Paddock ML, Chang C, Xu Q, Abresch EC, Axelrod HL, Feher G, Okamura MY, Biochemistry. 2005 May 10;44(18):6920-8. PMID:[http:// | Quinone (QB) reduction by B-branch electron transfer in mutant bacterial reaction centers from Rhodobacter sphaeroides: quantum efficiency and X-ray structure., Paddock ML, Chang C, Xu Q, Abresch EC, Axelrod HL, Feher G, Okamura MY, Biochemistry. 2005 May 10;44(18):6920-8. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/15865437 15865437] | ||
[[Category: Protein complex]] | [[Category: Protein complex]] | ||
[[Category: Rhodobacter sphaeroides]] | [[Category: Rhodobacter sphaeroides]] | ||
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[[Category: integral membrane protein]] | [[Category: integral membrane protein]] | ||
[[Category: quinone movement]] | [[Category: quinone movement]] | ||
[[Category: rhodobacter | [[Category: rhodobacter sphaeroide]] | ||
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Mar 20 15:22:06 2008'' | ||
Revision as of 16:22, 20 March 2008
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| , resolution 2.25Å | |||||||
|---|---|---|---|---|---|---|---|
| Ligands: | , , , , , , , , , and | ||||||
| Gene: | pufL (Rhodobacter sphaeroides), pufM (Rhodobacter sphaeroides), puhA (Rhodobacter sphaeroides) | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
Structure of a quintuple mutant of photosynthetic reaction center from rhodobacter sphaeroides
OverviewOverview
The photosynthetic reaction center (RC) from purple bacteria converts light into chemical energy. Although the RC shows two nearly structurally symmetric branches, A and B, light-induced electron transfer in the native RC occurs almost exclusively along the A-branch to a primary quinone electron acceptor Q(A). Subsequent electron and proton transfer to a mobile quinone molecule Q(B) converts it to a quinol, Q(B)H(2). We report the construction and characterization of a series of mutants in Rhodobacter sphaeroides designed to reduce Q(B) via the B-branch. The quantum efficiency to Q(B) via the B-branch Phi(B) ranged from 0.4% in an RC containing the single mutation Ala-M260 --> Trp to 5% in a quintuple mutant which includes in addition three mutations to inhibit transfer along the A-branch (Gly-M203 --> Asp, Tyr-M210 --> Phe, Leu-M214 --> His) and one to promote transfer along the B-branch (Phe-L181 --> Tyr). Comparing the value of 0.4% for Phi(B) obtained in the AW(M260) mutant, which lacks Q(A), to the 100% quantum efficiency for Phi(A) along the A-branch in the native RC, we obtain a ratio for A-branch to B-branch electron transfer of 250:1. We determined the structure of the most effective (quintuple) mutant RC at 2.25 A (R-factor = 19.6%). The Q(A) site did not contain a quinone but was occupied by the side chain of Trp-M260 and a Cl(-). In this structure a nonfunctional quinone was found to occupy a new site near M258 and M268. The implications of this work to trap intermediate states are discussed.
About this StructureAbout this Structure
1YF6 is a Protein complex structure of sequences from Rhodobacter sphaeroides. Full crystallographic information is available from OCA.
ReferenceReference
Quinone (QB) reduction by B-branch electron transfer in mutant bacterial reaction centers from Rhodobacter sphaeroides: quantum efficiency and X-ray structure., Paddock ML, Chang C, Xu Q, Abresch EC, Axelrod HL, Feher G, Okamura MY, Biochemistry. 2005 May 10;44(18):6920-8. PMID:15865437
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