Electron transfer dynamics: Zusman equation versus exact theory

2009 ◽  
Vol 130 (16) ◽  
pp. 164518 ◽  
Author(s):  
Qiang Shi ◽  
Liping Chen ◽  
Guangjun Nan ◽  
Ruixue Xu ◽  
YiJing Yan
Keyword(s):  
Electron Transfer ◽  
Exact Theory ◽  
Equation Versus

ELECTRON TRANSFER THEORY REVISITED: QUANTUM SOLVATION EFFECT

2006 ◽  
Vol 05 (03) ◽  
pp. 685-692 ◽  
Author(s):  
PING HAN ◽  
RUI-XUE XU ◽  
PING CUI ◽  
YAN MO ◽  
GUOZHONG HE ◽  
...  
Keyword(s):  
Electron Transfer ◽  
Relaxation Time ◽  
Close Relation ◽  
Longitudinal Relaxation Time ◽  
Inverse Temperature ◽  
Exact Theory ◽  
Transfer Theory ◽  
Electron Transfer Theory ◽  
Rate Processes ◽  
Classical Picture

The effect of solvation on ET rate processes has been investigated on the basis of the exact theory constructed in J. Phys. Chem. B110:11438, 2006. The nature of solvation has been studied in close relation with the mechanism of ET processes. The resulting Kramers' turnover and Marcus' inversion characteristics have been analyzed accordingly. The classical picture of solvation has been found to be invalid when the solvent longitudinal relaxation time is short compared with the inverse temperature.

A light optical diffractometer for electron microscopical images operating in line

1978 ◽  
Vol 36 (1) ◽  
pp. 86-87
Author(s):  
P. Bonhomme ◽  
A. Beorchia
Keyword(s):  
Electron Microscopy ◽  
Electron Transfer ◽  
Electron Microscope ◽  
Image Converter ◽  
Coherent Light ◽  
Spatial Filters ◽  
Electron Image ◽  
Electron Microscopical ◽  
Working Parameters ◽  
Amorphous Part

We have already described (1.2.3) a device using a pockel's effect light valve as a microscopical electron image converter. This converter can be read out with incoherent or coherent light. In the last case we can set in line with the converter an optical diffractometer. Now, electron microscopy developments have pointed out different advantages of diffractometry. Indeed diffractogram of an image of a thin amorphous part of a specimen gives information about electron transfer function and a single look at a diffractogram informs on focus, drift, residual astigmatism, and after standardizing, on periods resolved (4.5.6). These informations are obvious from diffractogram but are usualy obtained from a micrograph, so that a correction of electron microscope parameters cannot be realized before recording the micrograph. Diffractometer allows also processing of images by setting spatial filters in diffractogram plane (7) or by reconstruction of Fraunhofer image (8). Using Electrotitus read out with coherent light and fitted to a diffractometer; all these possibilities may be realized in pseudoreal time, so that working parameters may be optimally adjusted before recording a micrograph or before processing an image.

Flavin radicals, conformational sampling and robust design principles in interprotein electron transfer: the trimethylamine dehydrogenase-electron-transferring flavoprotein complex

2004 ◽  
Vol 71 ◽  
pp. 1-14
Author(s):  
David Leys ◽  
Jaswir Basran ◽  
François Talfournier ◽  
Kamaldeep K. Chohan ◽  
Andrew W. Munro ◽  
...  
Keyword(s):  
Electron Transfer ◽  
Dimensional Space ◽  
Three Dimensional ◽  
Kinetic Studies ◽  
Molecular Assembly ◽  
Conformational Sampling ◽  
Trimethylamine Dehydrogenase ◽  
Key Residues ◽  
Electron Transferring Flavoprotein ◽  
Electron Transfer Complex

TMADH (trimethylamine dehydrogenase) is a complex iron-sulphur flavoprotein that forms a soluble electron-transfer complex with ETF (electron-transferring flavoprotein). The mechanism of electron transfer between TMADH and ETF has been studied using stopped-flow kinetic and mutagenesis methods, and more recently by X-ray crystallography. Potentiometric methods have also been used to identify key residues involved in the stabilization of the flavin radical semiquinone species in ETF. These studies have demonstrated a key role for 'conformational sampling' in the electron-transfer complex, facilitated by two-site contact of ETF with TMADH. Exploration of three-dimensional space in the complex allows the FAD of ETF to find conformations compatible with enhanced electronic coupling with the 4Fe-4S centre of TMADH. This mechanism of electron transfer provides for a more robust and accessible design principle for interprotein electron transfer compared with simpler models that invoke the collision of redox partners followed by electron transfer. The structure of the TMADH-ETF complex confirms the role of key residues in electron transfer and molecular assembly, originally suggested from detailed kinetic studies in wild-type and mutant complexes, and from molecular modelling.

Sign in / Sign up

Export Citation Format

Share Document