Perturbation wobbling

Fortunately, the imino forms of A and C and the enol forms of G and T occur rarely. Most A C and G T mispairs observed to date in high-resolution crystal structures (e.g., References 22 and 23) associate through a wobble configuration (14), with the bases sheared past one another relative to the Watson-Crick configuration (Table 1 and Fig. 1). These structural perturbations (Table 1 and Table 2) alter the patterns of atomic charges and accessibihty that are presumably required for protein recognition and enzymatic action (see discussion below). 

The noise (ripple) is a kind of a jitter of Eq which throws around and destroys some ions otherwise passing the gap. This effectively constrains the gap, so in curved FAIMS increasing the noise sharpens the peaks, improving the resolving power R (Figure 4.21a and b). As more ions are destroyed, the sensitivity drops. Like with oscillations due to E(t) by Equation 3.43, the magnitude of wobble due to Ec perturbation is proportional to its amplitude and inverse frequency. Hence greater... 

The differences in the thermodynamic destabilization intfoduced by various mismatches did not dictate the electrochemical response obtained at the corresponding films. For example, a GT mispair that caused a 6° decrease in the T of a 15-mer duplex gave the same attenuation in integrated current for the reduction of DM as a CA mispair that caused a 12° decrease in the T of the same duplex. Both perturbations in the orientations of bases involved in mispairs and increased base dynamics for wobble base pairs may disrupt stacking and attenuate rates of electron transfer. This attenuation may allow for the detection of mismatches with varying thermodynamic stabilities. 

This effect may be explained in terms of the quantum theory of electrodynamics. According to this theory each mode of the quantized radiation field possesses a zero-point energy of hu)/2. This implies that, even in the absence of external radiation, the mean square value of the time-depen-dent electric field is finite and that a hydrogen atom will experience a perturbation produced by the fluctuations in this field. These zero-point fluctuations cause the electron to wobble randomly in its orbit and so smear the charge over a greater volume of space. Since the electron is bound to the nucleus by a non-uniform electric field, the reduction in electron density causes a shift in the atomic energy levels. This Lamb shift, as it is now called, is greatest for those states in which iK0) is finite, i.e. the n states. 

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