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ELECTRO- AND MAGNETOBIOLOGY, 11(2), 97-108 (1992)

CHROMOSOME DNA AS A TARGET OF RESONANT INTERACTION BETWEEN Escherichia coli CELLS AND LOW-INTENSITY MILLIMETER WAVES lgor Ya. Belyaev, Yevgeny D. Alipov, and Victor S. Shcheglov SRC “Vidguk” Moscow Engineering Physics Institute 3 1 Kashirskoye sh. Moscow, 115409, Russia

ABSTRACT The method of anomalous viscosity time dependence (AVTD) was used to study the influence of nonthermal microwaves on the genome conformational state (GCS) of Escherichiu coli cells. 20-Gy X-rayed cells were exposed to circularly polarized microwaves at seven frequencies of the 5 1.62-5 1.84 GHz band in which linearly polarized electromagnetic radiation (EMR) resonantly inhibits repair of X-ray-induced changes in the GCS. At all the frequencies that were studied, right-handed-polarized microwaves effectively influenced the GCS of X-rayed cells, whereas left-handed polarization was virtually ineffective. And conversely, right-handed polarization was ineffective and the left-handed polarized EMR effectively influenced the GCS when intact cells were exposed to microwaves. The two resonance dependences of millimeter waves’ effect on the GCS of E. coli cells (both preliminarily irradiated and unirradiated by X-rays) had the same resonance frequency of 51.76 GHz, and a half-width of the resonance of about 100 MHz. Relative efficiency of circularly polarized components of EMR at this resonance frequency was studied, depending on the dose of radiation applied to the cells. It was shown that the effects of left- and right-handed EMRs become the same at 50 cGy. This dose is too small to damage any cellular structures except DNA. It was estimated that the dose induces about one single-strand DNA break per genome of the bacterial cell. Seen from the standpoint of the previously suggested physical model, the results suggest that the target of resonant interaction between E. coli cells and millimeter waves appears to be chromosomal DNA. 97 Copyright 0 1992 by Marcel Dekker, Inc.

98

BELYAEV, ALIPOV, AND SHCHEGLOV

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INTRODUCTION We had previously discovered the resonance effect of low-intensity millimeter waves on the genome conformational state (GCS) of Escherichia coli cells (1). Changes in the GCS were measured with the method of anomalous viscosity time dependency. The method is based on radial migration of DNA macromolecules in the Quette flow of a rotating cylinder viscosimeter (2,3) and is highly sensitive to hydrodynamic parameters of chromosomal DNA, which are determined by its molecular weight, nativity, and bonds with proteins. Linearly polarized microwaves in two frequency bands (41.25-41 S O GHz and 51.62-51.84 GHz) suppressed repair of the GCS in cells exposed to 20-30 Gy of Xrays. In both bands, the effect was frequency dependent with resonance frequencies of f l = 41.32 GHz and f2 = 51.76 GHz, respectively (43). It was established in subsequent studies that right- and left-handed circularly polarized EMR have different efficiency at resonance frequencies (4,6). Left-handed polarized microwaves at f = 41.32 GHz suppress repair of the GCS almost completely, whereas the right-handed polarizations are virtually ineffective. And conversely, left-handed-polarized EMR at& = 51.76 GHz was ineffective, whereas right-handed-polarized microwaves blocked repair of the GCS. The result confirmed our assumption that discrete transitions that occur in a living system in the millimeter range of the electromagnetic field obey selection rules of helicity. Further experiments revealed that the difference in the effects of right- and lefthanded-polarized EMRs of the same resonance frequency depends on the ellipticity coefficient (k) and grows, reaching maximal value at k- 1 (7). The study also showed that the sign of effective polarization changes for microwaves of both resonance frequencies (41.32 and 5 1.76 GHz) when intact cells (those not preliminarily irradiated by X-rays) are exposed. The results make it obvious that the 0-20 Gy range contains at least one dose that removes the difference between the efficiencies of subsequently applied circularly polarized EMRs of the same resonance frequency. The determination of the dose (or the minimal effective dose) is of key importance for the building of a physical model of resonance interaction, which, according to the hypothesis suggested earlier (8), is exercised through direct interaction between EMR and vibration modes in DNA. That was why the present study investigated relative efficiency of right- and left-handed-polarized microwaves at 51.76 GHz in relation to the dose of X-rays applied to the cells. To determine the sign of effective polarization and parameters of resonances in the 51.62-5 1.84 GHz band, we studied the effect of differently polarized millimeter waves on the GCS of intact cells and cells exposed to X-rays at a dose of 20 Gy.

MATERIALS AND METHODS E. coli cells were exposed to microwaves in Petri dishes, in a thin layer of M9 buffer as described earlier (1,2-7). The EMR frequency’s deviation was kept within f 1 MHz. The irradiation device could simultaneously irradiate three Petri dishes with EMR of one frequency but different polarizations: linear, left-handed circular,

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E. coli CELLS AND LOW-INTENSITY WAVES

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and right-handed circular. Circularly polarized radiation was obtained by transformation of linearly polarized EMR with the help of quarter-wave mica plates. The ellipticity coefficient with voltage along the axis of the beam in the zone of the irradiated object did not exceed 1.05 k 0.05 for both circularly polarized components. The simultaneously irradiated Petri dishes were separated with absorbing screens. Specific absorbed rate (SAR) was measured with calorimetric and acoustic methods (9). The distribution of power density (PD) in the zone of the irradiated Petri dishes was determined with Shottke diode probes. The average PD and SAR were determined with an accuracy of k 10%. In our conditions of irradiation, in the 51.625 1.84 GHz range, the PD = 1 pW/cm2 corresponded to SAR = 6 pW/g. Exposure of cells to X-rays in an RUP-150 device was described in earlier papers (1,4,5). Irradiation with 0.01-3 Gy was conducted at a dose rate of 0.2 Gy/min, and with larger doses at 0.8 Gy/min. The maximum energy of X-rays was 150 KeV. E. cofi K12 AB1157 cells were cultivated in Luria broth as described earlier (1). Cells of overnight cultures were resuspended at a concentration of (3-7) x 10' cells/ mL in M9 salt buffer. Following irradiation and subsequent incubation, the cell suspension from each Petri dish was divided into three equal aliquots of 1 ml each. The cells were then lysed in plastic test tubes, which were later used as replaceable stators of the rotating viscosimeter for the study of AVTD. Added to the 1 ml of each cell suspension were: 0.3 ml of LET-lysozyme (LET-medium: 0.5 M Na2 EDTA, 0.01 M Tris, pH 7) at a concentration of 6 mg/mL (11.906 u/mg, Cooper Biomedical); 1 mL of LET-sarcosy1 (2%, Serva); and 0.7 ml of LET-papain (3 mg/ml, Merck, in 10% glycerol), in order. The lysates were kept in the dark for 40 h at 30°C, and AVTD was then measured. AVTD was measured in a Zimm-Crothers viscosimeter with automatic registration of the rotor rotation period (2). AVTD curves were replicated three times for each variant of exposure. Maximum viscosity, the most sensitive parameter of AVTD, which is proportionate to the maximum rotor rotation period (T,J, was used to measure changes in the conformational state of the genome. The Student t-test was used to evaluate the difference between experimental and control values of T,,,.

RESULTS Figure 1 shows several AVTD curves, each obtained from three measurements in one experiment. Curve 1 is AVTD for lysates of intact cells. At the initial stage of measurement, viscosity increases (in proportion to the rotor rotation period) due to the radial migration of DNA macromolecules to the rotating rotor. Following deposition of DNA on the rotor's surface, viscosity drops to values characteristic of the solvent. Exposure of the cells to 20 Gy substantially reduces T,,, (Fig. 1, curve 2), which reflects changes in the hydrodynamic parameters of chromosomal DNA caused by induction of damage and changes in the spectrum of proteins bound. After exposure to 20 Gy, the AVTD curve, including the T,,, parameter, is restored to the control level if the cells are incubated for 90 min after irradiation (Fig. 1, curve 3). The process reflects repair of the GCS, including repair of the DNA damage. However, if the cell suspension is exposed to low-intensity EMR at the 51.76-GHz resonance

BELYAEV, ALIPOV, AND SHCHEGLOV

100

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b

20

,

101

,

,

11: 1

0

50

100 150 2 0 0 2 5 0

TIME

s

FIGURE 1 Dependence of rotor rotation period (7‘) in cell lysates on the measurement time (t). 1, Lysates of intact cells; 2, cells lysed after exposure to X-rays (20 Gy); 3, cells lysed after exposure to X-rays and subsequent incubation in M9 buffer (90rnin); 4,5,6, in the interval of 10-20 min of postradiation incubation, the cells were exposed to left-handed, right-handed, or Linearly polarized EMR (51.76 GHz, 100 pW/cm’, 10 rnin).

frequency (100 pW/cmz) during postradiation incubation, the repair of GCS is blocked. The blocking effect depends on the polarization of the microwaves. Right-handed circularly polarized EMR (Fig. 1, curve 5 ) is very effective. Left-handed circular polarization (Fig. l , curve 4) is virtually ineffective. Linear polarization’s efficiency is a mean of the circularly polarized ones (Fig. 1, curve 6). The significance of the level of differences in T,,, among curves 4, 5 , and 6 does not exceed 0.002. The blocking effect of millimeter waves can be assessed with the following formula (7):

a,‘x

€ = -

*,ax

-

x+i

- Tmaxx+EMR

x+I - T m a x x

where: -

1. T,,,

is the rotor’s maximum rotation period averaged from three independent measurements in lysates of E. coli cells lysed after exposure to X-rays; 2. T,,, x + , is the average T,,, in lysates of cells lysed after exposure to X-rays and 90-min incubation; subsequent 3. Tmaxx+EMR is the average T,,, in lysates of cells exposed to microwaves during the postradiation incubation. To study the frequency dependence of the effect, EMR of a preset frequency was applied for 5 min within 10-30 minutes after exposure to X-rays. We had shown that the effect of EMR of a resonant frequency did not depend on which part of this time interval the 5-min application of microwaves took place (4). The cells were incubated for 90 min after exposure to X-rays and prior t o lysis, as in the previous experiments. The frequency dependence obtained in one of the independent experiments is shown in Figure 2. Left-handed polarized microwaves did not affect repair of the GCS, while the frequency dependence of the effect of righthanded-polarized EMR had a resonance curve close to a normal distribution. The

E. coli CELLS AND LOW-INTENSITY WAVES

T

1.0

-

0.8

-

w

0.6

-

cr,

0.4

-

0.2

-

0.0

.-________

u

101

c4

w

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I

, " ' . , ' .

significance level of differences between the effects of components of circularly polarized EMRs at frequencies (0 of 51.72, 51.74, 51.76, and 51.78 GHz did not exceed 0.008. The parameters of the dependence (mean value?, which is equal to the resonant frequency in the case of symmetrical curves, and dispersion uj ) were assessed in a standard manner for n measurements: -

f =zJ;t,/zt,;O;=E(f;-f)'x I

I

I

tlxn/C€,x(n-l) I

The half-width of the resonance can be evaluated with the formula r, = 2.35 x a, given a normal distribution. In another experiment, cells were exposed to EMR at 51.62, 51.76, 51.80, and 51.84 GHz, with right-handed-polarized microwaves, which again proved to be more effective than left-handed-polarized ones. Therefore, the sign of the effective circularly polarized component (right-handed) does not change within the limits of the resonance under investigation. The resonance frequencies and half-widths of resonances for the effect of right-handed-polarized EMR are shown in Table 1. A comparison of the same type of frequency dependencies obtained in similar conditions shows that the resonance frequency remains quite stable = 51.76 0.01 GHz), whereas the half-widths of the resonances have a certain instability. But the absolute value of the resonance half-width is small comand therefore the sharpness of the pared to the resonance frequency (I',/?resonances is very high. Two independent experiments were also conducted to study frequency dependence of the effect of polarized microwaves on intact cells. In each of them, cells were exposed for 5 min to one of the five to six frequencies within the 51.62-51.84 GHz, 60-90 min prior to lysis. It had been shown that the EMR effect does not depend on the part of the 60-to 90-min interval within which the 51.76-GHz frequency is applied. The effect on the GCS of intact cells was assessed with the help of relative viscosity, which was determined using the following formula: _+

VI

= Tmax EMR

Tmax CONT

BELYAEV, ALIPOV, AND SHCHEGLOV

102

Table 1 Exposure of E. coli cells to circularly polarized EMR in the 5 1.62-5 1.84 GHz band Type of exposure

X-rays (20 Gy)

EMR

EMR

Blocking of the GCS repair

Effect

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+

100 5

Power density, pW/cmz Time of EMR exposure, min Effective polarization Resonance frequency, GHz Mean value, GHz Half-width of resonance, GHz Mean value, GHz

Relative viscosity 100 5

100 5

100

5 Left-handed

Right-handed 5 1.76

51.76 51.76 f 0.01 0.16 0.04 0.10 0.06

51.76 51.75 51.76 k 0.01 0.06 0.08 0.07 k 0.01

*

where: -

1. T,,, CONT is T,, averaged in three independent measurements in lysates of intact E. - coli cells; 2. T,,, E M R is average T,, in lysates of cells lysed after exposure to microwaves and subsequent incubation in M9 buffer. The results of one of the experiments are presented in Figure 3, which shows that right-handed-polarized microwaves have virtually no or very little effect on the GCS of E. coli cells. At the same time, there is a pronounced effect of left-handed-polarized EMR, which is obviously resonant frequency dependent. The difference in the effects of EMR’s circularly polarized components at every frequency of the resonance investigated, except the extreme two (5 1.68 and 51.84 GHz), had a significance level of p < 0.001. The second experiment, when EMR was applied to intact cells at 5 1.62, 5 1.68, 5 1.76, 5 1.80, and 5 1.84 GHz, also revealed a resonant effect of left-handedpolarized microwaves, and the virtual inefficiency of right-handed polarization.

1L7.

,

51.65

,

,

,

,

51.70

,

,

,

.

51.75

,

,

,

,

51.80

,

51.85

FREQUENCY, GHz

FIGURE 3 Dependence of the relative viscosity (7,) on the frequency of microwaves to which intact cells are exposed (100 pW/cmz, 5 min). 1, 2, Left- and right-handed circular polarization.

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E. coli CELLS AND LOW-INTENSITY WAVES

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It follows that the sign of effective circular polarization does not change within the investigated resonance. Table 1 presents an assessment of the half-width and resonance frequency of the observed frequency dependences. It can be seen that in spite of the inversion in the sign of effective polarization, the resonance frequency of the EMR effect on the GCS of intact and X-rayed cells does not change. The half-widths of the resonances do not change either within the limits of the error. Seven independent experiments were carried out to determine the dose required for the inversion in the sign of EMR’s effective polarization at 51.76 GHz. The effect of X-rays on the GCS of E. coli cells (Fig. 4A) was assessed by means of relative viscosity: qz =

-

-

‘maxX’

TmaxCONT

The AVTD peaks grow within the interval from 0.01 to 0.1 Gy with obvious difference from the control when the doses are 0.05 Gy (p < 0.05)’0.1 Gy (p < 0.003), and 0.2 Gy (p < 0.02). The further dependence of relative viscosity on the dose is characterized by gradual decrease until the dose reaches 20 Gy (not shown in Fig. 4). To determine relative efficiency on EMR’s circularly polarized components, cells were exposed to microwaves for 10 min during a 10- to 30-min interval after X-ray irradiation. As in the previous experiments, lysis was carried out 90 min after expo-

1.4

1

B

1.2 1. o 0.8

0.6 t

I

0

0.5

I

1.0

I

I

I

I

1.5

2.0

2.5

3.0

DOSE, Gy

FIGURE 4 Dose dependences: (A) of relative viscosity ( q 2 ) , which is determined after exposure of E. coli cells to X-rays; (B) of relative efficiency (x) of left-handed polarized EMR (51.76 GHz, 100 pW/cm*, 10 min).

104

BELYAEV, ALIPOV, AND SHCHECLOV

sure to X-rays. The results of the standard experiment are shown in Table 2. The relative efficiency of left-handed polarized EMR was assessed with the following formula: -

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K

=

a ,'x

RIGHT /',ax

LEFT

where: T,, R,GHT (T,, LEFT) is average T,, in lysates of X-rayed cells that were exposed to right-(left-)handed-polarized microwaves during postradiation incubation. As can be seen in Figure 4B, the relative efficiency of the left-handed polarized EMR decreases gradually with increasing dose. The decrease continues to a dose of 20 Gy (not shown in Fig. 4). The efficiency of left- and right-handed-polarized EMR therefore proves the same with one dose only (about 0.5 Gy), with both EMR's circularly polarized components exerting a statistically significant influence on radiation-induced repair of the GCS, as can be clearly seen in Table 2. Also note that the curves in Figure 4A and 4B cross the control level at approximately the same dose of X-rays.

DISCUSSION One of the main results of this work is that EMR's effective circular polarization within the limits of the 51.62-51.84 GHz resonance has a constant sign. We investigated the resonance with a sufficiently small increment: 20 MHz. The data suggest therefore that at any frequency from this band, only right-handed-polarized microwaves will have an effective influence on GCS repair induced by 20 Gy, and only left-handed polarization will be effective when intact E. coli cells are irradiated. A similar situation, but with a reverse sign of effective polarization for intact and X-rayed cells, had been discovered earlier for the 41.25-41 3 0 GHz frequency band (4,6,7). The totality of these results comprises a significant argument in favor of the existence of selection rules on helicity during discrete transitions in a living system. This view assumes that normally functioning cells have discrete levels between which transitions are carried out in the millimeter range of a coherent electromagnetic field. External low-intensity EMR can induce such transitions under two possible (but not independently sufficient) conditions: the quantum energy coincides with the value of Table 2 Examination of 10-min Effect of Circularly Polarized Microwaves (100 pW/cm*, 51.76 GHz) on E. coli Cells X-rayed in a dose of 0.5 Gy ~

Test number

Cell exposure

EMR polarization

T,,, f SE

6)

1

Control

-

55.0 f 0.9

2 3

X-rays X-rays and incubation X-rays and incubation with EMR

-

-

46.7 f 0.7 53.9 f 0.8

Right

39.7 f 0.7

Left

38.8 3~ 0.6

4 5

Significance level p(1,2) < p(1,3) > ~ ( 2 . 3 )< p(3,4) < p(33 < p(4,l) < p(4,5) > ~(5.1)<

0.002 0.1 0.003 0.0002 0.0002 0.0002 0.1 0.0002

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E. coli CELLS AND LOW-INTENSITY WAVES

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the allowed transition, and the latter satisfies the rules of selection, including selection for helicity. In this case, only quanta with definite helicity will cause these transitions. Since an EMR quantum can have only one of the two possible helicities, which correspond to two possible circular polarizations of microwaves, only one of the circularly polarized EMR components will be effective under particular conditions of irradiation. That was established by us experimentally for at least four stimulus variants. The small half-width of the resonance dependencies obtained, and the efficiency of superlow intensities of EMR with P D = W/cm2 (lo), are additional arguments for introducing a quantum approach into the explanation of resonance interactions between cells and millimeter waves (11-13). On the molecular level, the resonance effect of EMR on the GCS can be attributed to direct interaction with chromosomal DNA (4). In this case, the efficiency of circularly polarized millimeter waves is determined by the helicity of DNA sequences that interact with EMR and may be in either the B-form (the right-handed helix) or the Z-form (the left-handed helix). As an extension of the idea, a physical model describing the generation in DNA of collective modes over a wide frequency range (1010”) Hz (8) was suggested. According t o the model, collective modes are generated in the system of transverse hydrogen bonds in nucleotide pairs during local phase transitions of the order-disorder type, which occur, for example, during DNA-protein interactions. An interaction that lasts a sufficiently long time may assure a sharp resonance effect of microwaves. The greatest will be achieved when the EMR helicity coincides with the helicity of DNA sequences, in whose sugar-phosphate skeleton the longitudinal collective mode (polar phonon) of the same frequency exists. The experimental findings support the notion of DNA’s role in resonant interaction between cells and microwaves. Indeed, despite the inversion in the sign of effective polarization when exposing intact cells versus cells irradiated by 20 Gy, the resonance frequency and half-width of the resonance remain virtually unchanged. It should also be noted here that the same values of the resonance frequency (51.76 GHz) and the half-width of the resonance were obtained in the previous studies of the effect of linearly polarized EMR (43). Barring a chance coincidence of the results obtained, this means that in all three cases we deal with the same molecular target of the EMR effect, in which an intracellular electromagnetic field is generated. The presence of only one dose of X-rays in a wide range of doses, which changes the sign of effective EMR polarization when cells are exposed to it, shows that it is only at this dose that X-rays induce in the target of interest sufficient damage to change the conformation. The structure of DNA sequences that can be in either B- or Z-form is well known at present (14). These sequences are assumed to play an important role in regulation of elementary genetic processes such as transcription, replication, recombination, and repair. The experiment shows, among other things, that conformational transitions B%Z occur during transcription in the living cells (14,15). The relationship between B S Z transitions and supercoiling of DNA has been established (16). In view of the data obtained, the change in the sign of effective polarization has a logical explanation, given that ionizing radiation, which induces breaks in DNA, removes supercoils and thus may affect the intracellular relative content of Z- and B-forms along the same DNA sequence. Since the E. coli genome consists of only one circular chromosome, only one single-strand DNA break per genome may be enough for this. The number of DNA damages induced by ionizing radiation in cells of different types is known (17,18). Extrapolation of data obtained in experiments with eukary-

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otic cells shows that a dose of about 1 Gy induces one single-strand DNA break per genome of an E. coli cell. The data obtained in experiments with E. coli cells suggest that it requires a higher dose to induce one single-strand break in the genome. Given the radiation-induced output of other DNA damages, there is a clear coincidence in the order of magnitude of the dose that induces a single-strand DNA damage and the dose that equalizes the effects of the EMR’s circularly polarized components. We do not know of data proving that this dose can induce damage in other molecules, which could also change their conformation. It should be noted here that the dose-inducing change in the sign of effective polarization coincides with the dose that changes the sign of the X-ray effect (Fig. 4). Our as-yet-unpublished results demonstrate that effects of cell irradiation in smaller doses are determined not by DNA damage but by changes in the spectrum of DNA-bound proteins. The GCS changes induced by ionizing radiation in small doses that do not cause damage to any cellular structures are due to the portion of the radiation energy that is transmitted by excitation processes (19). Changes in the AVTD curves after irradiation of lysates begin to appear precisely at the X-ray dose that causes the inversion in the sign of effect when intact cells are irradiated. In other words, DNA damages that change the hydrodynamic parameters of the bacterial genome first appear with this dose. It appears that the above-mentioned coincidences are not fortuitous and therefore unambiguously point to DNA as the target of the resonant interaction between cells and low-intensity millimeter waves. Let us also note here that the resonance frequency of 51.76 GHz remains the same for at least four tested strains of E. coli K12: AB1157, RM117, (362, and N99 (43, unpublished data). Moreover, the resonance effect of microwaves on the GCS of ABl157 cells manifests itself irrespective of the growth stage, beginning with the middle logarithmic stage, when cells are exposed to EMR. The results seem to suggest that at least the collective mode under consideration (51.76 GHz) is generated in a relatively universal manner over the greater part of the cell cycle in all strains investigated. Furthermore, the generation of this collective mode does not depend on the number of damages that appear in DNA when the cells are irradiated by doses of 0-20 Gy. We believe that the process of generation takes place in the DNA-protein complex bound to the membrane. Collective modes can also interact with external EMR in other DNA sequences. The result of interaction with circularly polarized EMR will be determined by the relative content of interacting sequences that are in the form (B- or Z-) corresponding to the EMR helicity. It would seem that when E. coli cells are exposed to 1 Gy, about half the DNA sequences that interact with EMR of 51.76 GHz are in the Z-form and the other half are in the B-form. In coming works we shall show how changes in the length of the bacterial chromosome can shift the resonance frequency of EMR’s influence on E. coli cells. We shall also present electrophoretic characteristics of proteins whose cooperative interaction with DNA determines the resonance response of cells to microwaves and low-intensity electromagnetic fields of extremely low frequency.

ACKNOWLEDGMENTS The authors are thankful to L. E. Bockstahler, C. D. Lytle, J-L. Sagripanti, and M. L. Swicord for the provision of enzymes and reagents used in this work.

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REFERENCES

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1. Alipov, Ye. D., Belyaev, I. Ya., Yedneral, D. I., Izmailov, D. M., Lukashevsky, K. V., Obukhova, L. K., Okladnova, 0. V., and Shcheglov, V. S . : Specific ef-

fect of millimeter waves on genome and some genetic processes in norm and during radiation-induced damage. In: Proceedings of the Workshop on Genetic Effects of Charged Particles (K. G. Amirtaev and S. Kozubek, eds.), JINR Press, Dubna, 1989, pp. 150-160 (in Russian). 2. Uhlenhopp, E. L., and Zimm, B. H.: Rotating cylinder viscosimeters. In: Methods in Enzymology, Vol. 21 (C. H. W . Hirs and S . N. Timasheff, eds.), Academic Press, New York, 1973, pp. 483-491. 3. Shafer, R. H., Laiken, N., and Zimm, B. H.: Radial migration of DNA molecules in cylindrical flow. I . Theory of the free-draining model, Biophys. Chem., 2, 180-188, 1974. 4. Belyaev, I. Ya., Alipov, Ye. D., Shcheglov, V. S . , and Lystsov, V. N.: Effect of

millimeter waves on radiation-induced repair of genome conformational state. In: Workshop on DNA Repair and Mutagenesis Induced by Radiation. Proceedings (Ye. D. Krasavin, ed.), JINR Press, Dubna, 1990, pp. 242-261, (in Russian). 5. Belyaev, I. Ya., Alipov, Ye. D., Shcheglov, V. S . , and Lystsov, V. N.: Resonance effect of microwaves on the genome conformational state of E. coli cells, Z. Naturforsch., 47c. 172-178, 1992. 6. Belyaev, I. Ya., Shcheglov, V. S., and Alipov, Ye. D.: Existence of selection rules on helicity during discrete transitions of genome conformational state of E. coli cells exposed to low-level millimeter radiation, Bioelectrochem. Bioenerg., 27, 405-41 1, 1992. 7. Belyaev, I . Ya., Shcheglov, V. S . , and Alipov, Ye. D.: Selection rules on helicity

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9. 10.

11. 12. 13. 14.

during discrete transitions of the genome conformational state in intact and Xrayed cells of E. coli in millimeter range of electromagnetic field. In: Charge and Field Effects in Biosystems-3 (M. J. Allen, S . F. Cleary, A. E. Sowers, and D. D. Shillady, eds.), Birkhauser, Boston, 1992, pp. 115-126. Arinichev, A. D., Belyaev, 1. Ya., Samedov, V. V., and Sitko, S . P.: Physical model of direct electromagnetic field effect on genome conformational state. In: First Congress of the European Bioelectromagnetics Association. Transactions, Brussels, 1992, p. 1. Polnikov, I. G., and Putvinsky, A. V.: Acoustic detection of absorption of millimeter waves in biological objects, Biofizika, 33, 893-894, 1988 (in Russian). Belyaev, I. Ya., Alipov, Ye. D., Shcheglov, V. S . , and Radko, S . P.: Chromosomal DNA as a target of resonance interaction between living cells and low intensive electromagnetic waves. In: First Congress of the European Bioelectromagnetics Association. Transactions, Brussels, 1992, p. 42. Frolich, H.: Long range coherence and energy storage in biological systems. Int. J. Quantum Chem., 2, 641-652, 1968. Keilmann, F.: Triplet-selective chemistry: A possible cause of biological microwave sensitivity, Z. Naturforsch., 41c, 795-798, 1986. Sitko, S. P., and Gizhko, V. V.: Towards a quantum physics of the living state, J . Biol. Phys., 18, 1-10, 1991. Jaworski, A., Hsieh, W-T., Blaho, J. A., Larson, J . E., and Wells, R. D.: Lefthanded DNA in vivo, Science, 238, 773-777, 1987.

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