Experimental studies of the mechanism of biological organisation.

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One of the most difficult things to understand about living things is their ability to maintain themselves in an active organised state without running down. Physicists expect all systems to be governed by thermodynamics the second law of which states that the disorder, or entropy, of a system will always increase. For a living system this is a sentence of decay, disorder and death and that is the fate of all life. However thermodynamics allows an ordered state to continue provided it is maintained out of equilibrium and a flow of free energy through the system acts to increase the entropy outside of the system. So thermodynamics is compatible with the existence of living things but it does not provide any information on the mechanisms by which living systems organise and maintain themselves.This research programme will provide several experimental tests of a long standing and controversial hypothesis that very long wavelength modes of vibration in the terahertz (THz) region of the electromagnetic spectrum play an important role in the self-organisation of biological systems. THz waves have wavelengths of the order of 300 microns and lie between radio waves and infrared radiation in the electromagnetic spectrum. The idea that THz modes are exploited in mechanisms of biological organisation is appealing since at the temperatures at which living things operate the thermal energy is able to excite waves with energies up to 6 THz. Consequently it is possible that rotational and vibrational modes excited in this frequency range by chemical interactions in living things will have been selected by evolution to play a role in biological organisation. A crucial issue is whether THz modes live long enough to be important in biological activity. The detailed theoretical work is conflicting and the experimental evidence for long-lived THz modes is sparse and controversial. What is needed to resolve this question is experiments. However laboratory sources of THz radiation are weak, with power levels in the micro W to mille W range and these low power levels are the principle reason why it has not been possible to carryout a convincing test of this hypothesis previously. In this programme we will exploit the unique intense THz beamline on the ALICE accelerator at the Daresbury laboratory that is equipped with a tissue culture facility. The beamline has a high peak power, 70 kW, and a low average power 24 mW. The high peak power is delivered in a short pulse of < 1 pico second. The high peak power is important because it enables us to overcome the problem of THz absorption by water. The low average power makes it possible to eliminate thermal effects which can have a major impact on biological systems. Finally some of the experiments could not be done without the ability to maintain the specimens in the tissue culture facility.THz radiation has the potential to influence multiple levels of biological organisation; direct interactions at the molecular level have the potential to affect cell behaviour, which in turn will influence cell-cell interactions thereby affecting the development of the whole organism. We will therefore investigate the role of THz at all three levels of biological organisation by studying:-1) The role of THz modes in biomolecular interactions2) The influence of THz modes on the growth and differentiation of stem cells.3) The influence of THz modes on the normal development of zebra fish embryos. Finally in order to consolidate research collaborations between physical scientists and life scientists in the University of Liverpool we will invite teams from this community to submit proposals for small scale speculative research programmes.