Sharp Resonances in Yeast Growth Prove Nonthermal Sensitivity to Microwaves

Grundler, W.; Keilmann, F.

doi:10.1103/physrevlett.51.1214

Cited by 120 publications

(46 citation statements)

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“…These investigations have been performed on either extracted DNA or polynucleotides. Other than a preliminary study reported in 1987 (4), no studies have been conducted in this spectral region on living biological systems, though there have been investigations in the microwave region (1-cm wavelength) on living yeast (5). Those studies demonstrated a direct effect on yeast growth with a strong frequency dependence with resonances as narrow as 8 MHz.…”

mentioning

confidence: 99%

“…Within 2 min of completion of exposure to the FEL beam, the culture medium was removed from the culture chamber, and fresh medium containing [3H]thymidine (specific activity of 5 ,uCi/ml; 1 Ci = 37 GBq) was injected into the chamber. The isotope-containing chamber was then placed in a 37°C incubator for 30 min, after which 2.5% glutaraldehyde and MEM without fetal bovine serum was injected.…”

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confidence: 99%

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Free electron laser irradiation at 200 microns affects DNA synthesis in living cells.

Berns

Bewley²,

Sun³

et al. 1990

Proc. Natl. Acad. Sci. U.S.A.

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We describe the effect of a 200-pm wavelength free electron laser beam on the ability of asynchronized and synchronized mammalian tissue culture cells to incorporate tritiated thymidine. Compared to controls (unexposed cells), a significant proportion of exposed cells exhibited a reduction in isotope incorporation. The results suggest that this wavelength may affect DNA synthesis.Recent studies on DNA lattice dynamics have utilized the apparent existence of vibrational and resonant modes of the DNA molecule in the infrared spectral region between 100 and 600 ,um (1)(2)(3) (Fig. 1).In all of the experiments, each cell culture was exposed to 100 pulses of the FEL operating at 0.5-0.33 Hz.The cells used were Chinese hamster (Cricetulus griseus) ovary cells obtained from the American Type Culture Collection (CCL no. 61).The cells were maintained in GIBCO's minimum essential medium (MEM) with 10% (vol/vol) fetal bovine serum and were regularly subcultured with 0.25% trypsin. In preparation for the experiment, the cells were grown in Corning 150-cm2 tissue culture flasks. Approximately 11 hr before transporting the cells, halfwere placed in 6 .ul ofColcemid per ml of medium for 3 hr. The mitotic phase cells were removed by agitation and were centrifuged for 5 min at 200 x g. The synchronized cells were resuspended in fresh MEM with 10% fetal bovine serum and injected into standard Rose tissue culture chambers.For the next 8 hr the cells were allowed to attach to the fused silica windows in the Rose chamber. It had been previously shown that the fused silica windows transmit 60% ofthe FEL wavelength at 200 pum (4). After 8 hr the cells were finishing G1 ofthe cell cycle and beginning the DNA synthesis (S) phase. At this point the cells were chilled to 40C on ice for 3 hr during their transport to the laser in Santa Barbara. Previous studies had demonstrated that the cells could be held in S phase for up to 6 hr by this method. When returned to 37°C, the cells continued through the cell cycle. The total cell cycle for CHO cells is 12.5 hr, and the length of S phase is 4 hr. Once at the FEL laser facility, the cells were placed at room temperature 2-5 min prior to irradiation. The nonsynchronized CHO cells were subjected to identical temperature changes and culture conditions as the synchronized cells.For irradiation, each chamber was placed into a holder that was prealigned so that the FEL beam was directed onto the fused silica surface with the cells growing as a monolayer on the opposite side of the glass. Because of the tight adherence of the cell membrane to the glass surface, there was no water interface between the cells and the glass surface. In this configuration, the beam passed directly through the window and exposed the cells without passing through any intervening fluid. A 3-mm-thick stainless steel shield with a 6-mm aperture was placed over the glass surface so that the FEL beam exposed only those cells under the aperture window. All the other cells growing on the glass served as control cells and,...

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mentioning

confidence: 99%

mentioning

confidence: 99%

Free electron laser irradiation at 200 microns affects DNA synthesis in living cells.

Berns

Bewley²,

Sun³

et al. 1990

Proc. Natl. Acad. Sci. U.S.A.

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“…This surprising result has been confirmed several times (10,11), most recently by the experiments of Grundler and Keilmann (12). Subsequently, Webb (13) reported that cultures of Bacillus megaterium and Escherichia coli displayed complex Raman spectra from 50 to 2600 cm-l when they were metabolically active.…”

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confidence: 73%

Transient fluorescence in synchronously dividing Escherichia coli.

Layne¹,

Bigio²,

Scott³

et al. 1985

Proc. Natl. Acad. Sci. U.S.A.

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Using a spectrometer equipped with an optical multichannel analyzer as the detector, we observed the Stokes laser-Raman spectra of metabolically synchronous Escherichia coli from 100 to 2100 cm-'. After more than 400 separate recordings, at cell concentrations of 107-l08 per ml, no Raman lines attributable to the metabolic process nor to the cells themselves were found. However, we did find that synchronous E. coli cultures become more fluorescent during a limited phase of the division cycle. This transient increase in fluorescence may be ascribed to a variation in the redox state of a chemical species within the bacteria or to a variation of the intracellular optical field. The effect is reproducible in synchronous cultures and it is not seen in asynchronous ones. The results suggest that spectral features seen in previous laserRaman spectra of synchronous bacteria (taken with scanning monochromators) are due to a time-dependent variation in bacterial fluorescence.Over the past two decades considerable interest has focused on the possibility that biological macromolecules support collective excitations. Such excitations are supposed to extend over large regions of a protein or DNA macromolecule and are expected to have unusually long lifetimes because of nonlinear interactions. The first biophysical theory to point this out was developed by Frohlich (1,2). In this generic theory, a collection of oscillators interact nonlinearly as they exchange quanta with an ambient heat bath. When metabolic energy pumps these oscillators, a coherent state evolves that is reminiscent of a Bose-Einstein condensation. Later, Davydov (3, 4) proposed a complimentary but more specific model for energy transport in a-helical proteins. In this theory, ATP hydrolysis transfers energy to amide-I vibrations (mainly C=O stretch) in the peptide groups of a helix. Dissipation due to dipole-dipole coupling among amide-I groups is overcome by nonlinear interactions involving hydrogen bonds. The balance between dispersion and nonlinearity results in a solitary wave (soliton) that travels along the helix. Like

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“…The single mode, which can exhibit long range correlations is thus akin to laser-like coherent pumped phonons in the range of 10 9 to 10 11 Hz. The proposed frequency is in the microwave range, 31 and corresponds to recognized protein conformational transitions in the range of nanoseconds to 10 picoseconds. Fröhlich's proposal may be seen in a context of quantum field theory whose proponents have viewed living matter as a sea of electric dipoles organized by electret states, and the consequent ordering of water around biomolecules, providing collective states of ordered symmetry.…”

Section: Fröhlich Coherence Quantum Field Theory and Microtubulesmentioning

confidence: 99%

Quantum states in proteins and protein assemblies: The essence of life?

Hameroff¹,

Tuszyński²

2004

SPIE Proceedings

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Activities in living cells are performed by protein conformational dynamics which in turn are governed by quantum mechanical van der Waals London forces in intra-protein "hydrophobic" pockets. In assemblies of proteins with periodic lattice geometry such as cytoskeletal actin and microtubules (as well as ordered water on their surfaces), Bose-Einstein condensation, quantum coherent superposition and quantum computation with entanglement may occur as a collective effect of these forces due to metabolic coherent phonon pumping. Decoherence can be avoided through isolation/shielding by actin gelation, Debye layer screening and water/ion ordering and topological quantum error correction. As an example, quantum spin transfer through organic molecules is more efficient at higher temperatures than at absolute zero. The unitary oneness and ineffability of living systems may depend on mesoscopic/macroscopic quantum states in protoplasm.Keywords: Bose Einstein condensation, cytoskeleton, decoherence, evolution, life, London forces, microtubules, protein conformation, quantum coherence, quantum superposition OIL VERSUS WATER: HYDROPHOBIC POCKETS IN PROTEINSAll chemistry including biochemistry is based on quantum interactions, so living systems-like non-living systemsdepend on quantum states at the level of chemical bonds. However the unitary oneness and ineffability of living systems have suggested that higher level quantum properties such as Bose-Einstein condensation, quantum coherent superposition and entanglement may operate in biology.1-3 But quantum effects are apparently washed out at scales larger than individual atoms or sub-atomic particles, at warm temperatures, and in aqueous media. Thus the possibility of quantum states playing functional roles at mesoscopic or macroscopic scales in "warm, wet and noisy" biological systems seems unlikely due to environmental decoherence. On the other hand evolution may have solved the decoherence problem so that mesoscopic/macroscopic quantum states are essential features of biological systems. 4 Living cells are 80% water, and many polar, water soluble biomolecules play key roles in cell function. However there are also extensive non-polar "oily" regions in living cells which exclude water. These are called hydrophobic regions, and they occur within proteins 5 , lipid membranes and nucleic acids (e.g. the "pi stack" of DNA). If organized quantum states exist in cells they are presumably integrated among hydrophobic regions of various cellular components and organelles. However here we consider only proteins and geometric arrays of proteins (i.e. protein assemblies) in cytoplasm, the bulk protoplasm between cell membrane and nucleus.Proteins are folded chains of amino acids strung together by peptide bonds (Figure 1, top). Each of the twenty different amino acids which comprise proteins have distinct side groups with varying degrees of polarity and water solubility. Amino acids with side groups (or "residues") which are non-polar and insoluble in water ("hydrophobic...

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Sharp Resonances in Yeast Growth Prove Nonthermal Sensitivity to Microwaves

Cited by 120 publications

References 8 publications

Free electron laser irradiation at 200 microns affects DNA synthesis in living cells.

Free electron laser irradiation at 200 microns affects DNA synthesis in living cells.

Transient fluorescence in synchronously dividing Escherichia coli.

Quantum states in proteins and protein assemblies: The essence of life?

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