Electronic properties of biological

Pethig, R. "Dielectric and Electronic Properties of Biological Materials" John Wiley Sons, New York, 1979 p. 153. 

Denis, A., and A. Pullman Theoretical study of the electronic properties of biological purines and pyrimidines. III. Theoret. Chim. Acta (Berlin) 7, 110 (1967). Del Re, G. A simple MO-LCAO method for the calculation of charge distributions in saturated organic molecules. J. Chem. Soc. (London) 4031 (1958). 

Pethig, R. (1979). Dielectric and Electronic Properties oF Biological Materials. Wiley, Chichester, England. 

R. Pethig, Dielectric and electronic properties of biological materials, Wiley, UK (1979). 

Pethig R. 1979. Dielectric and Electronic Properties of Biological Materials. Chichester, John Wiley. 

Nyboer, J., 1970b. Electrorheometric properties of tissues and fluids. Ann. N.Y. Acad. Sci. 170, 410—420. Pethig, R., 1979. Dielectric and Electronic Properties of Biological Materials. John Wiley. 

Empirical energy functions can fulfill the demands required by computational studies of biochemical and biophysical systems. The mathematical equations in empirical energy functions include relatively simple terms to describe the physical interactions that dictate the structure and dynamic properties of biological molecules. In addition, empirical force fields use atomistic models, in which atoms are the smallest particles in the system rather than the electrons and nuclei used in quantum mechanics. These two simplifications allow for the computational speed required to perform the required number of energy calculations on biomolecules in their environments to be attained, and, more important, via the use of properly optimized parameters in the mathematical models the required chemical accuracy can be achieved. The use of empirical energy functions was initially applied to small organic molecules, where it was referred to as molecular mechanics [4], and more recently to biological systems [2,3]. 

Several copper enzymes will be discussed in detail in subsequent sections of this chapter. Information about major classes of copper enzymes, most of which will not be discussed, is collected in Table 5.1 as adapted from Chapter 14 of reference 49. Table 1 of reference 4 describes additional copper proteins such as the blue copper electron transfer proteins stellacyanin, amicyanin, auracyanin, rusticyanin, and so on. Nitrite reductase contains both normal and blue copper enzymes and facilitates the important biological reaction NO) — NO. Solomon s Chemical Reviews article4 contains extensive information on ligand field theory in relation to ground-state electronic properties of copper complexes and the application of... 

Cyclopropanation is an important synthetic method, and enantioselective catalytic reactions of olefins and diazoacetates provide access to valuable products with biological activity. In general, these reactions are conducted in anhydrous solvents and in several cases water was found to diminish the rate or selectivity (or both) of a given process. Therefore it came as a surprise, that the Cyclopropanation of styrene with (+)- or (-)-menthyl diazoacetates, catalyzed by a water-soluble Ru-complex with a chiral bis(hydroxymethyldihydrooxazolyl)pyridine (hm-pybox) ligand proceeded not only faster but with much Wgher enantioselectivity (up to 97 % e.e.) than the analogous reactions in neat THF or toluene(8-28 % e.e.) (Scheme 6.34) [72]. The fine yields and enantioselectivities may be the results of an accidental favourable match of the steric and electronic properties of hm-pybox and those of the menthyl-dizaoacetates, since the hydroxyethyl or isopropyl derivatives of the ligand proved to be inferior to the hydroxymethyl compound. Nevertheless, this is the first catalytic aqueous cyclopropanation which may open the way to other similar reactions in aqueous media. 

D. M. Smith, S. D. Wetmore, and L. Radom, Theoretical Studies of Coenzyme-Bi2-Dependent Carbon-Skeleton Rearrangements, in Theoretical Biochemistry—Processes and Properties of Biological Systems, L. A. Ericksson, Ed., Elsevier, Amsterdam, The Netherlands, 2001, pp. 183-214. Electronic structure calculations are applied to the understanding and prediction of how enzymes can lower the barriers to the 1,2-shifts in radicals that occur in reactions catalyzed by B12. 

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