1. Light activated bionanodevices Presented at CSIR B60 Conference - Pretoria Unit: National Laser Centre Dr. Raymond Sparrow Senior Researcher in Biophotonics 27 th February 2006

2. Slide 2 © CSIR 2006 www.csir.co.za Agenda Nano – overview Why nano? Bionanodevice project at NLC Outline of project Nanotechnology Overview Advantages Problems Energy transfer using LHC Principles for energy supply and transfer Bionanotechnology Why bio-nano? Energy conversion Outline of component Kinesin motor protein Principles for movement

3. Slide 3 © CSIR 2006 www.csir.co.za Nano - overview There is a constant drive to reduce the size of components and machines. The properties of materials at the nanoscale are very different to the properties in there bulk phase. Technology using components on the nanometer scale. Utilising and manipulating individual atoms or molecules. Bio-nanotechnology uses biological materials or systems.

4. Slide 4 © CSIR 2006 www.csir.co.za Nanotechnology ADVANTAGES New materials New properties Greater efficiency Reduced size (compactness) PROBLEMS The assembly of components. Interconnecting components into working mechanisms The control of components

5. Slide 5 © CSIR 2006 www.csir.co.za Bionano - overview Many problems of nanoscale mechanisms have been overcome in nature. Act at the nanoscale More energy efficient. Hence a great interest in investigating biological materials and systems. Actin, Myosin, Kinesin (movement) ATPsynthase, Photosynthetic pigments (Energy transduction) Many biological systems are self assembling (Protein/DNA/Membranes)

6. Slide 6 © CSIR 2006 www.csir.co.za A Light activated bio-nanodevice Creating a device that will move a tubule/rod in 8nm controllable steps. The device has three sections (modular). It uses the principles of:- - PHOTOSYNTHESIS - ATPsynthase ATP PRODUCTION - KINESIN MOTOR PROTEIN MOVEMENT

7. Slide 7 © CSIR 2006 www.csir.co.za A Light activated bio-nanodevice SECTION A – ENERGY TRAPPING (LIGHT HARVESTING) AND TRANSPORT. SECTION B – ENERGY CONVERSION. SECTION C – MOVEMENT (CAN BE AN ALTERNATIVE COMPONENT).

8. Section A ENERGY TRAPPING (LIGHT HARVESTING) AND TRANSPORT.

9. Slide 9 © CSIR 2006 www.csir.co.za Chlorophylls (Chl) a & b Absorb red (600 - 700 nm) and blue (400 - 500 nm) light Antennae chlorophylls gather light Harvested light energy passed to specialized Chl molecules, a reaction center Chlorophylls arranged in photosynthetic units Generally several hundred light-harvesting antennae Chl for each Chl at a reaction center Chemical reactions of photosynthesis begin at reaction centers

10. Slide 10 © CSIR 2006 www.csir.co.za ABSORPTION OF LIGHT BY CHLOROPHYLLS a and b

11. Slide 11 © CSIR 2006 www.csir.co.za

12. Slide 12 © CSIR 2006 www.csir.co.za AFM OF LHC GONÇALVES, BUSSELEZ, LÉVY, SEGUIN AND SCHEURING J,STRUCTURAL BIOL. 149 (2005)

13. Slide 13 © CSIR 2006 www.csir.co.za A PHOTOSYNTHETIC UNIT

14. Section B ENERGY CONVERSION.

15. Slide 15 © CSIR 2006 www.csir.co.za RC ATPsynthase ADP + Pi ATP ADP + Pi [H + ] PHOTONS LIPOSOME VESICLE Steinberg-Yfrasch et.al (1998)

16. Section C MOVEMENT

17. Slide 17 © CSIR 2006 www.csir.co.za The structure of Kinesin

18. Slide 18 © CSIR 2006 www.csir.co.za Kinesin carrying a cargo

19. Slide 19 © CSIR 2006 www.csir.co.za

20. Current and future work

21. Slide 21 © CSIR 2006 www.csir.co.za Collaborations Professor Barzda, University of Toronto. To determine LH II organisation for potential energy transfer domain size. Utilising non-linear microscopy to detect fluorescence, second and third harmonic data. To corroborate this technique with CD spectroscopy data and develop a micro-CD spectroscope. Dr.Grobler – NWU (Potchefstroom) vesicle production.

22. Slide 22 © CSIR 2006 www.csir.co.za Laser experimental requirements Femtosecond Pulsed Laser System Excitation Wavelength Regions 400 – 900nm (1.5x1015 Photons cm-2). Probe Wavelength Regions 400 – 900nm (1013 Photons cm-2). To Measure Ultra-fast Transient Absorption and Fluorescence Data. To Measure Intensity Dependent Data.

23. Slide 23 © CSIR 2006 www.csir.co.za Finally You are very welcome to visit our brand new Biophotonics Group website! (www.csir.co.za/biophotonics)