František Jelínek

Vibrations in Microtubules

Vibrations in microtubules and actin filaments are analysed using amethod similar to that employed for description of lattice vibrationsin solid state physics. The derived dispersion relations show thatvibrations in microtubules can have optical and acoustical branches.The highest frequency of vibrations in microtubules and in actinfilaments is of the order of 108 Hz. Vibrations are polar andinteraction with surroundings is mediated by the generatedelectromagnetic field. Supply of energy from hydrolysis of guanosinetriphosphate (GTP) in microtubules and of adenosine triphosphate(ATP) in actin filaments may excite the vibrations.

ELECTROMAGNETIC ACTIVITY OF YEAST CELLS IN THE M PHASE

Electromagnetic activity around yeast mitotic cells (Saccharomyces cerevisiae) was measured in the frequency range 8–9 MHz and special care was taken to extract reliable information from the raw signals. The characteristic of cold-sensitive tubulin mutants tub2-401 and tub2-406, which come to arrest before mitosis at a restrictive temperature (14°C) and which re-enter mitosis upon a shift back to a permissive temperature (28°C), was used to prepare synchronized mitotic cells. Immunofluorescence microscopy using an antitubulin antibody was used to analyze microtubular structures. The arrested tub2-401 mutant that had back-shifted to permissive temperature displayed no microtubules and no electromagnetic activity around the cells. In contrast, the arrested cells of the mutant tub2-406 displayed developed, but aberrant, nonfunctional microtubules and a high electromagnetic activity around the cells. The electromagnetic activity around the arrested mutant tub2-401 back-shifted to permissive temperature peaks at four time points which may coincide with (i) formation of the mitotic spindle, (ii) binding of chromatids to kinetochore microtubules, (iii) elongation of the spindle in anaphase A, and (iv) elongation of the spindle in anaphase B. The profile of the electromagnetic activity around the synchronized mutant tub2-406 at permissive temperature seems to be delayed by the time required for aberrant nonfunctional microtubules to be depolymerized. Experimental results presented in this paper support Pohls idea of existence of the electromagnetic field around yeast cells.

Microelectronic sensors for measurement of electromagnetic fields of living cells and experimental results

Microelectronic sensors are used for measurements of electromagnetic fields generated by synchronized cultures of yeast cells. Cold sensitive mutant tub2-401 of Saccharomyces cerevisiae is used. The measured electromagnetic signals in the frequency range from 8 to 9 MHz are compared with evolution of the reassembled microtubules. The detected signals peak in the time interval 25-30 min and 45-60 min after the release of the cells from the restrictive to the permissive temperature. The first maximum corresponds to the stage when the mitotic spindle is formed and binds chromatids. The second maximum is measured when the processes of anaphase A and of anaphase B take place.

Endogenous Electric Field and Organization of Living Matter

Microtubules in eucaryotic cells form electrically polar structures, which satisfy conditions for excitation, energy condensation, and generation of endogenous electromagnetic field with strong electric near zone component. Large energy supply connected with continuous rebuilding of the microtubular structure and very likely with activity of motor proteins, and interfacial slip layer at the microtubule surface protecting vibrations in microtubules from viscous damping of the cytosol are important conditions for excitation and formation of coherent state. Generated electric field can exert a driving force for directed transport. The Wiener-Lévy process with symmetry breaking is used to describe motion of molecules and charges. Motion of molecules with diameter 1 and 5 nm at distances up to 50 nm is analysed. Transport driven by the electric field with inseparable thermal component has greater probability to reach the target than transport by thermal motion itself. Transport of electrons display similar dependence. Probability of any action depending on the ratio of the random and of the deterministic component of motion should be high enough to provide small number of errors but sufficiently low to comply with requirements for evolutionary changes.

Electric field around microtubules

Abstract Living cells are organized by the cytoskeleton with a fundamental role of microtubules. The mechanisms of organization are largely unknown. We analyze the vibrations in the microtubules which are polar and are accompanied by polarization waves. Oscillating electric field generated around microtubules can be as high as 10 5 Vm −1 and may have an important role in information system and mass transport in living cells. Energy from hydrolysis of guanosine triphosphate (GTP) stored in microtubules can excite the vibrations above thermodynamic equilibrium level.

Electromagnetic Field of Microtubules: Effects on Transfer of Mass Particles and Electrons

Biological polar molecules and polymer structures with energy supply (such as microtubules in the cytoskeleton) can get excited and generate an endogenous electromagnetic field with strong electrical component in their vicinity. The endogenous electrical fields through action on charges, on dipoles and multipoles, and through polarization (causing dielectrophoretic effect) exert forces and can drive charges and particles in the cell. The transport of mass particles and electrons is analyzed as a Wiener-Lévy process with inclusion of deterministic force (validity of the Bloch theorem is assumed for transport of electrons in molecular chains too). We compare transport driven by deterministic forces (together with an inseparable thermal component) with that driven thermally and evaluate the probability to reach the target. Deterministic forces can transport particles and electrons with higher probability than forces of thermal origin only. The effect of deterministic forces on directed transport is dominant.

Measurement of Electrical Oscillations and Mechanical Vibrations of Yeast Cells Membrane Around 1 kHz

Fröhlich postulated coherent polar oscillations as a fundamental biophysical property of biological systems. Recently, Pelling et al. (2004, 2005) detected mechanical vibrations of yeast cell membrane with atomic force microscope (AFM) and analyzed by Fourier analysis in the frequency range 0.5–2u2009kHz with amplitudes of the order of 1u2009nm. This article describes the measurement of electric activity of yeast cells in the acoustic frequency range and of mechanical vibrations of cell membrane. Spectrum analyzer and electrically and electromagnetically screened box with point sensor and amplifiers fed by batteries were used for measurement of synchronized and non synchronized tubulin mutants of yeast cells. We show that the electric activity of synchronized cells in the M phase is greater that of non synchronized cells. That corresponds to the findings of Pohl et al. (1981). Obtained results of measurement of cell electric activity are in good agreement with AFM findings.

MICROTUBULES IN BIOLOGICAL CELLS AS CIRCULAR WAVEGUIDES AND RESONATORS

The microtubules in the cellular cytoskeleton have a fundamental role in the living processes of biological cells. They are hollow cylinders which resemble circular waveguides or cylindrical resonators. The cutoff and resonant frequencies of the transverse magnetic and transverse electric modes of the microtubule cavities are in the band of soft x-rays. This suggests the possibility of interaction of electromagnetic cavity modes with inner electrons in atoms (e.g., in carbon, nitrogen, and oxygen). Biological cells (e.g., the yeast cells of spherical shape) may also represent cavity resonators. In this case, the resonant frequencies may be in the infrared region.

Measurement system for experimental verification of Fröhlich electromagnetic field

Abstract Biological activity of cells is connected with the generation of an electromagnetic field as follows from experimental measurements. Sophisticated experimental facilities should be used to detect these fields. We describe an experimental system for measurement of weak biological signals. The sensitivity of the system allows measurement of cellular emission the power of which is to the order of about 105 W in the f W in the frequency range from 1 to 100MHz.

Experimental Investigation of Electromagnetic Activity of Yeast Cells at Millimeter Waves

The direct detection of oscillations in biological cells may deliver strong evidence for Fröhlichs theory of coherent excitation in biological systems. Some results of measurement at millimeter waves published in the literature are mentioned. A laboratory equipment for the measurement of mm waves excitations in yeast cells is described. The measurement system is controlled by computer and measured data are stored in the computer memory for evaluation and for statistical processing. Some results of the evaluation are given.