Rieske iron protein

Complex III is an example of the consilient mechanism for elasticity that includes the coupling of hydrophobic association with development of an elastic force. In particular, the Rieske iron protein (RIP) of Complex III resides on the cytoplasmic side and contains a long hydrophobic a-helix that passes through the lipid bilayer from the cytoplasmic side to emerge on the matrix side with charged residues that combine to anchor the iron protein to the membrane. On the cytoplasmic side, a sequence of about 15 residues that is continuous with the transmembrane anchor... 

Hypothesis 2 Hydrophobic Association Within Complex III of the Hydrophobic (FeS) Tip of the Rieske Iron Protein with the Hydrophobic Ubiquinol-containing Qo Site Causes Extension and Damping of Internal Chain Dynamics in the Tether of the Iron Protein... 

Consilient Mechanisms for Electron Transfer/Proton Transport Reside in the Movement of the Rieske Iron Protein FeS Center... 

Molecular Structures That Show Relocation of the Globular Domain of the Rieske Iron Protein... 

Stretched Tether Connecting the Membrane Anchor to the Globular Component of the Rieske Iron Protein When Hydrophobically Associated at the Qo Site... 

Is the Tether of the Rieske Iron Protein a Free Standing (Kinetically Free) Chain When the FeS Center Is at the... 

Figure 8.14. Stereo view of the monomer of Complex III the cytochrome bci complex of chicken. Shown are ligands plus the Rieske Iron Protein, where the inhibitors stigmatellin and antimycin are used to show FeS center relocation on reduction. The Rieske Iron Protein anchors in one monomer and then reaches across to accept an electron at its FeS center from the Qo site of the second monomer. (A) With inhibitors, the FeS center is in position, with the tip of the globular component of the Rieske Iron Protein pointing directly downward at the level of the Qo site, where it is to be reduced by the second component of the functional homodimer. (Prepared using the crystallographic results of Zhang et al. as...

Figure 8.15. Stereo view of yeast cytochromes b and Cl of Complex III showing Qo and heme Ci binding sites for the FeS center of the Rieske Iron Protein. Neutral residues are given in light gray, aromatic residues in black, other hydrophobic residues in gray, and charged residues in white in order to show visually the relative hydrophobicity of the two sites. Note at the Qo site that ubiquinol would reside at the base of a hydrophobic pit into which the hydrophobic FeS tip of the Rieske Iron Protein fits (see Figure 8.16), whereas the heme Cj site is not as hydrophobic. Also note that the hydrophobic residues L263 and V264...

S Is the Tether Contracted When the FeS Center of the Rieske Iron Protein Resides at the Heme Ci Site ... 

Figure 8.18. An expanded stereo view of the complete yeast Complex HI dimer of the qrtochrome bci complex. Identified are the tethers of Rieske Iron Protein connecting the membrane anchor to the globular component. The purpose is to demonstrate that the tether sequence from A66 to V94 is free standing in the structure and would, therefore, be capable of exhibiting the changes in entropy on extension required to produce an entropic elastic...

Movement of Rieske Iron Protein, Both Metaphorically and Literally, Represents a Movable Cusp of Insolubility... 

Formation of the hydrophobic association between the hydrophobic tip of the Rieske Iron Protein and the hydrophobic ubiquinol-containing site stretches an interconnecting chain segment. This extended chain segment functions as a free-standing tether originating from an anchor in the membrane and bridging... 

The nuclear-encoded proteins are inserted into both inner and outer mitochondrial membranes, the intermembrane space, and the matrix and there are several different mechanisms involved. As mentioned above there is no apparent requirement for a presequence on proteins which insert specifically into the mitochondrial outer membrane. For proteins destined for the inner mitochondrial membrane, a stop-transfer mechanism is proposed. Thus some information in the peptide must stop the complete transfer of the protein into the mitochondrial matrix, enabling the protein to remain in the inner mitochondrial membrane. For some proteins in the intermembrane space (for example the Rieske iron-sulphur protein associated with the outer face of complex III), a particularly complicated import pathway... 

Rieske proteins are constituents of the be complexes that are hydro-quinone-oxidizing multisubunit membrane proteins. All be complexes, that is, bci complexes in mitochondria and bacteria, b f complexes in chloroplasts, and corresponding complexes in menaquinone-oxidizing bacteria, contain three subunits cytochrome b (cytochrome 6e in b f complexes), cytochrome Ci (cytochrome f in b(,f complexes), and the Rieske iron sulfur protein. Cytochrome 6 is a membrane protein, whereas the Rieske protein, cytochrome Ci, and cytochrome f consist of water-soluble catalytic domains that are bound to cytochrome b through a membrane anchor. In Rieske proteins, the membrane anchor can be identified as an N-terminal hydrophobic sequence (13). 

Rieske, J. S. In Nonheme Iron Proteins Role in Energy Conservation San Pietro, E., Ed. The Antioch Press Yellow Springs, OH, 1965, 461-468. 

R)-2-METHYLMALATE DEHYDRATASE NICOTINATE DEHYDROGENASE NITRATE REDUCTASE NITRITE REDUCTASE PHENYLALANINE MONOOXYGENASE PROLYL 3-HYDROXYLASE PROLYL 4-HYDROXYLASE PROTOCATECHUATE 3,4-DIOXYGENASE PROTOCATECHUATE 4,5-DIOXYGENASE RIESKE IRON-SULFUR PROTEIN RUBREDOXIN... 

RIBULOSE-5-PHOSPHATE 4-EPIMERASE RIESKE IRON-SULFUR PROTEIN Ring reversal (or ring inversion),... 

Cinnamaldehyde complexes with iron, 12 246 Circular dichroism flavocytochrome b, 36 271 magnetic, see Magnetic circular dichroism Rieske and Rieske-type proteins, 47 113, 115-116... 

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