Energy Transfer in Proteins

Stryer L. Energy transfer in proteins and polypeptides. Radiat. Res. 1960 (2) 432-451. 

Such a method has been used, for example, by Epand (54) in a glucagon while Galley and Stryer (54b) studied triplet-triplet energy transfer in proteins as a criterion of proximity. 

Several groups have studied energy transfer in proteins theoretically and experimentally. To explore the energy transfer pathways in PYP, we developed a theoretical tool with which energy transport phenomena can be analyzed in atomistic detail. We proposed a new method to define microscopic energy conductivity in terms of interatomic energy flux (Ishikura and Yamato 2006). 

FIGURE 14.2 Indole is a typical molecule or side group (of the peptide tryptophan) for excitation energy transfer in proteins. 

Ward, W. W., and Cormier, M. J. (1978). Energy transfer via protein-protein interaction in Renilla bioluminescence. Photochem. Photobiol. 27 389-396. 

The important criterion thus becomes the ability of the enzyme to distort and thereby reduce barrier width, and not stabilisation of the transition state with concomitant reduction in barrier height (activation energy). We now describe theoretical approaches to enzymatic catalysis that have led to the development of dynamic barrier (width) tunneUing theories for hydrogen transfer. Indeed, enzymatic hydrogen tunnelling can be treated conceptually in a similar way to the well-established quantum theories for electron transfer in proteins. 

Visser NV, Borst JW, Hink MA, van Hoek A, Visser AJWG (2005) Direct observation of resonance tryptophan-to-chromophore energy transfer in visible fluorescent proteins. Biophys Chem 116 207-212... 

Kato, N., Pontier, D. and Lam, E. (2002). Spectral profiling for the simultaneous observation of four distinct fluorescent proteins and detection of protein-protein interaction via fluorescence resonance energy transfer in tobacco leaf nuclei. Plant Physiol. 129, 931-42. 

D. G. Searcy, T. Montenay-Garestier, and C. Helene, Phenylalanine-to-tyrosine energy transfer in the archaebacterial histone-like protein HTa, Biochemistry 28, 9058-9065 (1989). 

T. H. Watts, H. E. Gaub, and H. M. McConnell, T-cell-mediated association of peptide antigen and major histocompatibility complex protein detected by energy transfer in an evanescent wave-field, Nature 320, 176-179 (1986). 

The theory of electron transfer in chemical and biological systems has been discussed by Marcus and many other workers 74 84). Recently, Larson 8l) has discussed the theory of electron transfer in protein and polymer-metal complex structures on the basis of a model first proposed by Marcus. In biological systems, electrons are mediated between redox centers over large distances (1.5 to 3.0 nm). Under non-adiabatic conditions, as the two energy surfaces have little interaction (Fig. 5), the electron transfer reaction does not occur. If there is weak interaction between the two surfaces, a, and a2, the system tends to split into two continuous energy surfaces, A3 and A2, with a small gap A which corresponds to the electronic coupling matrix element. Under such conditions, electron transfer from reductant to oxidant may occur, with the probability (x) given by Eq. (10),... 

KINETIC ANALYSIS OF G PROTEIN-COUPLED RECEPTOR SIGNALING USING FLUORESCENCE RESONANCE ENERGY TRANSFER IN LIVING CELLS... 

Cogdell, R.J. and Thomber, J.P. 1979. The preparation and characterization of different types of light-harvesting pigment-protein complexes. In Chlorophyll organization and Energy Transfer in Photosynthesis . (CIBA Foundation Symposium 61, new series). (Excerpta Medica, Amsterdam), pp. 61-79. 

Finally, it should be noted that singlet-state lifetimes in [Re(L)(CO)3(bpy)], are long enough to allow for ultrafast electron or energy transfer in supramolecular assemblies, at surfaces or molecule/nanoparticle interfaces, see Sect. 7.3. Indeed, a hot electron injection has been seen with Ti02 nanoparticles [42] or in Re-labeled redox proteins [43],... 

The cytochromes are the electron carrier heme proteins occurring in the mitochondrial respiratory chain.449 There are five cytochromes linking coenzymes Q (ubiquinone) and 02 in this electron transport chain (Scheme 7). Cytochromes are also involved in energy transfer in photosynthesis. The iron atom in cytochromes cycles between the Fe11 and Fe111 states, i.e. they are one-electron carriers, in contrast to CoQ and the NADH flavins they act upon which are two-electron carriers. Thus, one molecule of reduced CoQ transfer its two high potential electrons to two molecules of cytochrome b, the next member of the electron transport chain. 

Although diffusion is a slow process compared to energy transfer and electron transfer at the shortest distances, it can be an exceptionally effective way to move electrons and protons over long distances. However, unlike the hard-wired cofactor chains that guide electron transfer in protein complexes, diffusion faces the problem of directing where... 

Electron transfer in proteins generally involves redox centers separated by long distances. The electronic interaction between redox sites is relatively weak and the transition state for the ET reaction must be formed many times before there is a successhil conversion from reactants to products the process is electronically nonadiabatic. A Eandau-Zener treatment of the reactant-product transition probability produces the familiar semiclassical expression for the rate of nonadiabatic electron transfer between a donor (D) and acceptor (A) held at fixed distance (equation 1). Biological electron flow over long distances with a relatively small release of free energy is possible because the protein fold creates a suitable balance between AG° and k as well as adequate electronic coupling between distant redox centers. 

The question of energy transfer through proteins by various mechanisms has been considered in a recent symposium (Augenstine, 1960) and will not be discussed here, nor shall we discuss the studies of protein and amino acid luminescence from the solid state (phosphorescence) Debye and Edwards (1952, 1956). The photoinactivation of proteins will also not be considered. The recent paper by McLaren and Luse (1961) is suggested as a leading reference. 

Germain-Desprez, D., Bazinet, M., Bouvier, M. and Aubry, M. (2003) Oligomerization of transcriptional intermediary factor 1 regulators and interaction with ZNF74 nuclear matrix protein revealed by bioluminescence resonance energy transfer in living cells. J. Biol. Chem. 278, 22367-22373. 

The subject of energy transfer in phycobilisomes and their sub-structures already has a large literature (see Ref. 65 for a review), mostly beyond the scope of this chapter. However, two of these sub-structures - trimeric C-phycocyanin from the thermophilic cyanobacterium Mastigocladus laminosus and hexameric C-phycocyanin from the cyanobacterium Agmenellum quadruplicatum-have very recently become respectively the third and fourth photosynthetic pigment-protein complexes for which structural models based on single-crystal X-ray diffraction near atomic resolution are now available (Refs. 66,67 and Chapter 11). Since these are presently the only such complexes, in addition to the two already discussed (Sections 5 and 6), it seems appropriate to conclude this review of exciton effects with some brief remarks on these C-phycocyanin structures. 

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