Página 1 desde 25 resultados
The electrostatic interaction between plastocyanin (PC) and cytochrome f (cyt f), electron transfer partners in photosynthesis was studied using Brownian dynamics (BD) simulations. By using the software package MacroDox, which implements the BD algorithm of Northrup et al. (Northrup, S. H., J. O.
The prominent basic patch seen in the atomic structure of the lumen-side domain of turnip cytochrome f, consisting of Arg209 and Lys187, 58, 65, and 66, was proposed to be an electrostatically complementary docking site for its physiological electron acceptor, plastocyanin [Martinez, S. E., Huang,
Cytochrome f and plastocyanin from the cyanobacterium Phormidium laminosum react an order of magnitude faster than their counterparts from chloroplasts when long-range electrostatic interactions have been screened out by high salt concentration [Schlarb-Ridley, B. G., et al. (2002) Biochemistry 41,
The role of electrostatic interactions in determining the rate of electron transfer between cytochrome f and plastocyanin has been examined in vitro with mutants of turnip cytochrome f and mutants of pea and spinach plastocyanins. Mutation of lysine residues Lys58, Lys65 and Lys187 of cytochrome f
The orientation of poplar plastocyanin in the complex with turnip cytochrome f has been determined by rigid-body calculations using restraints from paramagnetic NMR measurements. The results show that poplar plastocyanin interacts with cytochrome f with the hydrophobic patch of plastocyanin close to
Most biological functions, including photosynthetic activity, are mediated by protein interactions. The proteins plastocyanin and cytochrome f are reaction partners in a photosynthetic electron transport chain. We designed a 3D computer simulation model of diffusion and interaction of spinach
The role of the acidic patches of spinach plastocyanin in the interaction with a soluble form of turnip cytochrome ƒ was studied by a combination of site-directed mutagenesis, NMR spectroscopy and kinetic analysis. The charge of the two 'eastern' patches, consisting of conserved acidic residues
Brownian Dynamics (BD) computer simulations were used to study electrostatic interactions between turnip cytochrome f (cyt f) and spinach plastocyanin (PC). Three different spinach PC structures were studied: The X-ray crystal structure of Xue and coworkers [(1998) Protein Sci 7:2099-2105] and the
We have investigated the electron transfer (ET) reactions between turnip cytochrome f, and the native and NO2-Tyr83-modified forms of spinach plastocyanin (PCu) at 10.0 degrees C and ionic strength 0.200 M(NaCl), in both directions as a function of pH. The PCu(II)/cytochrome f(II) rate constants in
In general, inter-protein electron transfer proceeds via the formation of transient complexes. The initial stage of the interaction between plastocyanin (PCu) and cytochrome f (cyt f ) from plants is mediated by complementary electrostatics. Given the diffuse nature of its acidic patch, parsley PCu
Part of the petCA operon was cloned and the sequence of the cytochrome f gene from the moderately thermophilic cyanobacterium Phormidium laminosum determined. A partial sequence of the petC gene encoding the Rieske iron-sulphur protein was also obtained. The cytochrome f gene encodes a mature
Plastocyanin (PC) and its physiological reaction partner cytochrome (cyt) f form a complex which is electrostatically stabilized by interactions between complementary localized charges. We have measured the kinetics of intracomplex electron transfer between several reduced cytochromes and PC using
Spinach plastocyanin and turnip cytochrome f have been covalently linked by using a water-soluble carbodiimide to yield an adduct of the two proteins. The redox potential of cytochrome f in the adduct was shifted by -20 mV relative to that of free cytochrome f, while the redox potential of
Soluble turnip cytochrome f has been purified from the periplasmic fraction of Escherichia coli expressing a truncated petA gene encoding the precursor protein lacking the C-terminal 33 amino-acid residues. The protein is identical [as judged by 1H-NMR spectroscopy, midpoint redox potential (+ 365
Plastocyanin can be covalently cross-linked to the monomeric cytochrome f from turnip by incubation in the presence of a water-soluble carbodiimide. The adduct between the two proteins has a molecular weight of approximately 43,000 suggesting a 1:1 stoichiometry between the two proteins of the