Electrostatic modulation

P Swaren, D Golemi, S Cabantous, A Bulychev, L Maveyraud, S Mobashery, JP Samana. X-ray structure of the Asn276Asp variant of the Escherichia coli TEM-1 (3-lactamase direct observation of electrostatic modulation in resistance to inactivation by clavulanic acid. Biochemistry 38 9570-9576, 1999. 

Equation 10.12 is more informative than the equivalent Equation 3.21 for interpreting the influence of temperature under IPC conditions. Equation 10.12 indicates that the experimental capacity factor is actually the weighted average of the electrostatically modulated retention factors of the free analyte and that of the paired analyte. Notably, the global A7/° for IPC retention can be thought of as a weighted average of the retention of both free (electrostatically tuned) analyte and paired analyte. 

Naray-Szabo, G., 1997, Electrostatic modulation of electron transfer in the active site of heme peroxidases, J. Biol. Inorg. Chem. 2 135nl38. 

Another aspect of electrostatic modulation of redox systems is metal cofactor interactions. Although these interactions are surprisingly uncommon in biological systems, metal-cofactor interactions have been well documented in certain families of enzymes such as bacterial alcohol dehydrogenases. These enzymes utilize the pyrroloquinolinequinone (PQQ) system as a redox cofactor (Figure 12) [45]. In these systems, it has been established that Ca + serves as additional cofactors in the enzymatic processes catalyzed by PQQ-dependent proteins [46]. 

He, B. and Wilson, E.A. (2003) Electrostatic modulation in steroid receptor recruitment of LXXLL and FXXLF motifs. Molecular and Cellular Biology, 23, 2135-2150. 

Electrostatic Modulation of Electromagnetically Induced Nonthermal Responses in Biological Membranes... 

Presently there exists no generally accepted theory of how very weak electromagnetic fields couple nonthermally to a biosystem. This is the basis for part of the controversy. Some of the hypotheses that have been suggested to explain such nonthermal interactions of the electric field component will be reviewed herein with an emphasis on those that focus on interactions with biological membranes. It will then be shown how some of these hypotheses might be tested by electrostatically modulating the response. Electrostatic modulation can be achieved by modifying the electrochemical environment of the system. 

M. A. Noble, S. Gul, C. S. Verma, and K. Brocklehurst, Biochem. J., 351, 732 (2000). Ionization Characteristics and Chemical Influences of Aspartic Acid Residue 158 of Papain and Caricain Determined by Structure-Related Kinetic and Computational Techniques Multiple Electrostatic Modulators and Active-Centre Chemistry. 

Click Chemistry Interactive for a self-study module interatomic electrostatic interactions. 

Hu, W. Z., Haddad, P. R., Tanakar, K., and Hasebe, K., Modulation of the separation selectivity of inorganic anions in electrostatic ion chromatography using acidic eluents, Analyst, 125, 241, 2000. 

Mehler EL, Guarnieri F (1999) A self-consistent, microenvironment modulated screened coulomb potential approximation to calculate pH-dependent electrostatic effects in proteins. Biophys J 75 3-22. 

The modulation of the charge of the adsorbed atom by the vibrations of heavy particles leads to a number of additional effects. In particular, it changes the electron and vibrational wave functions and the electrostatic energy of the adatom. These effects may also influence the transition probability and its dependence on the electrode potential. 

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