S. COMOROSAN, S. POLOSAN, M. APOSTOL

1. LOCALIZED EXCITATIONS INDUCED IN BIOLOGICAL MACROMOLECULES BY HIGH DENSITY PHOTONSSuggestions for a novel concept- Biological Optical Matter S. COMOROSAN, S. POLOSAN, M. APOSTOL

2. ASK NOT WHAT PHYSICS CAN DO FOR BIOLOGY, ASK WHAT BIOLOGY CAN DO FOR PHYSICS. P. Hänggi

3. A possible suggestion: BIOLOGICAL SPECTROSCOPY S. Comorosan

4. OUTLINE: • Local polypeptide geometry- structural changes under high density photons (HDP) (=514 nm) • Optical spectroscopy • Circular dichroism- ellipticity estimation b) Enzyme activity- SOD and CAT mechanisms • Alterations under strong oxidative effects • Preservation of activity under HDP c) Theoretical considerations

5. Light interactions in biological systems : • UV – oxidative effects - molecules photoionization, free radicals discharge, local disruption of large molecules aggregations. • Visible light – weakly absorbed – may induce local matter polarization.

6. In this context: Irradiation of complex biological structures with high density green photons may induce electric dipoles by polarization effects. The induced dipoles interact with external electromagnetic field (optical forces) and with one another, leading to organized material structures like molecular aggregates, micro-particles, etc. known in physics as “OPTICAL MATTER”.

7. Bovine Serum Albumine For ultraviolet transitions n* (220 nm) * (209 nm) Irradiation =514 nm Light irradiation intensity 104-105 Lx

8. Optical spectroscopy- absorption and fluorescence spectra Obs:- uv irradiation strongly modifies the spectra by disrupting the molecular structures, while the green light reduces the disrupting effects

9. Structural ellipticity alteration Circular dichroism spectroscopy UV light induces defolding processes witch reduce the ellipticity of the macromolecules Green light inhibits the defolding processes preserving native helical structures

10. Mean residual ellipticity estimations  - measured circular dichroism (in milidegree) r – number of aninoacids residues [SA]- serum albumine concentration

11. Enzyme activity- SOD and CAT mechanisms UV irradiation disrupts the enzyme macromolecular structure inhibiting its biological activity Green light preserves the native structure maintaining its biological activity at normal levels

12. Physico-chemical mechanism of GL-irradiation HOMO Under GL  LUMO Obs: the active center of the enzyme is located at the L-Histidine level Polarization changes under green light

13. Theoretical considerations: Under light with the frequency  and electric field E, dipoles p=E are induced interacting with one another, involving an interaction energy: =ω/c when R»1, the interaction energy becomes: where  is the angle interaction between E and R This is a long range interaction (1/R2)

14. At short-distance limit, U becomes: • which is short range interaction between two dipoles. • Obs: • We may expect an ordered state occurring for induced dipoles with a crystalline like structure • Short range interactions may lead to localized domains of organized biological matter • Long range interaction disturbs the arrangement between localized domains • We term these light induced aggregates- “Biological Optical Matter”

15.  GL Dispersed molecules Aggregate of macromolecules

16. Final remarks: Light interaction with matter generates a new force, known as “optical force” leading to new material properties- “optical matter” In biological systems, our model suggests that such optical manipulations may induce what we term “biological optical matter” Dipolar interaction results in the lowering energy of the biological system as compared with individual molecules, generating more stable and less reactive matter. In the biological optical matter, a series of known light interaction effects, like UV denaturation, disruption of internal chemical bonds, generation of free radical are partially inhibited.