3H1K: Chicken Cytochrome Bc1 Complex With Zn++ And An Iodinated Derivative Of Kresoxim-Methyl Bound

Citation:
Abstract
The chicken mitochondrial ubiquinol cytochrome c oxidoreductase (bc(1) complex) is inhibited by Zn(2+) ions, but with higher K(i) ( approximately 3 microM) than the corresponding bovine enzyme. When equilibrated with mother liquor containing 200 microM ZnCl(2) for 7 days, the crystalline chicken bc(1) complex specifically binds Zn(2+) at 4 sites representing two sites on each monomer in the dimer. These two sites are close to the stigmatellin-binding site, taken to be center Q(o) of the Q-cycle mechanism, and are candidates for the inhibitory site. One binding site is actually in the hydrophobic channel between the Q(o) site and the bulk lipid phase, and may interfere with quinone binding. The other is in a hydrophilic area between cytochromes b and c(1), and might interfere with the egress of protons from the Q(o) site to the intermembrane aqueous medium. No zinc was bound near the putative proteolytic active site of subunits 1 and 2 (homologous to mitochondrial processing peptidase) under these conditions.
PDB ID: 3H1KDownload
MMDB ID: 71459
PDB Deposition Date: 2009/4/12
Updated in MMDB: 2009/12
Experimental Method:
x-ray diffraction
Resolution: 3.48  Å
Source Organism:
Similar Structures:
Biological Unit for 3H1K: eicosameric; determined by author and by software (PISA)
Molecular Components in 3H1K
Label Count Molecule
Proteins (20 molecules)
2
Mitochondrial Ubiquinol-cytochrome-c Reductase Complex Core Protein I
Molecule annotation
2
Mitochondrial Ubiquinol-cytochrome-c Reductase Complex Core Protein 2
Molecule annotation
2
Cytochrome B(Gene symbol: CYTB)
Molecule annotation
2
Mitochondrial Cytochrome C1, Heme Protein
Molecule annotation
2
Cytochrome B-c1 Complex Subunit Rieske, Mitochondrial(Gene symbol: UQCRFS1)
Molecule annotation
2
Mitochondrial Ubiquinol-cytochrome C Reductase 14 KDA Protein
Molecule annotation
2
Mitochondrial Ubiquinol-cytochrome C Reductase Ubiquinone- Binding Protein Qp-c
Molecule annotation
2
Mitochondrial Ubiquinol-cytochrome C Reductase 11 KDA Protein, Complex III Subunit Viii
Molecule annotation
2
Cytochrome B-c1 Complex Subunit Rieske, Mitochondrial(Gene symbol: UQCRFS1)
Molecule annotation
2
Mitochondrial Ubiquinol-cytochrome C Reductase 7.2 KDA Protein
Molecule annotation
Chemicals (36 molecules)
1
6
2
5
3
4
4
2
5
2
6
4
7
2
8
2
9
2
10
5
11
2
* Click molecule labels to explore molecular sequence information.

Citing MMDB
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