1 / 14

Part 3: Photoprotection

PHOTOBIOLOGY. Part 3: Photoprotection. Part 3: Photoprotection. Nadine Schubert Instituto de Ciencias del Mar y Limnología de la UNAM Unidad de Sistemas Arrecifales, Puerto Morelos, México. Photorespiration Water-water cycle Cyclic e - - transport. Energy dissipation.

rhian
Download Presentation

Part 3: Photoprotection

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. PHOTOBIOLOGY Part 3: Photoprotection Part 3: Photoprotection Nadine Schubert Instituto de Ciencias del Mar y Limnología de la UNAM Unidad de Sistemas Arrecifales, Puerto Morelos, México

  2. Photorespiration Water-water cycle Cyclic e-- transport Energy dissipation LIGHT ABSORPTION  UTILIZATION OF ABSORBED LIGHT ENERGY LIGHT Adjustment of antenna size State transition Light capture Thermal dissipation Xanthophyll cycle Photochemistry CO2 fixation Production of Oxygen Radicals Antioxidant systems Photodamage Repair and de novo synthesis Net photodamage

  3. LIGHT ABSORPTION  UTILIZATION OF ABSORBED LIGHT ENERGY Excess energy  Fv/Fm Photosynthesis Photoprotection  Fv/Fm  O2 Photoinactivation/Photodamage Irradiance

  4. Violaxanthin Cycle Yamamoto et al., (1962) XANTHOPHYLL CYCLE

  5. Protective pigment Energy dissipater Accessorypigment Energy collector Violaxantina Zeaxantina S2 Energía Clorofila a S1 S1 Qy Calor S0 PHOTOPROTECTION BY CAROTENOIDS Violaxanthin Zeaxanthin Energy Chlorophyll a Heat Antheraxanthin, Lutein

  6. NON-PHOTOCHEMICAL QUENCHING PS = 0 NPQ = 0 NPQ = (Fm-Fm’)/Fm’ PS = 0 1  NPQ  0 1  PS  0 1  NPQ  0 PS = 1 NPQ = 0

  7. Relationship between ZEA-content and Fv/Fm and NPQ Macrocystis pyrifera Dictyota dichotoma Uhrmacher et al. (1995) Garcia-Mendoza & Colombo-Pallotta (2007) Open symbols = light exposure to 150 mol m-2 s-1 Closed symbols = light exposure to 500 mol m-2 s-1

  8. Müller et al. (2001) NON-PHOTOCHEMICAL QUENCHING

  9. PHOTODAMAGE ATP ADP + Pi NADPH NADP + H+ 2H+ Fd 1O2 ATPase PQH2 PSII LHCII Cyt bf PSI LHCI PQ 1O2 PC H+ 2H2O O2+ 4H+ 2H+

  10. 3P680* P680 3O2 1O2* 3Car* 1Car HEAT PHOTODAMAGE PSII LHCII 1O2 2H2O O2+ 4H+  Carotenoids: -carotene - reaction center

  11. 3Chl* Chl 3O2 1O2* 3Car* 3Car* 1Car 1Car HEAT HEAT 1O2 PHOTODAMAGE PSII LHCII 2H2O O2+ 4H+  Carotenoids: zeaxanthin, lutein - PSII antennae

  12. CYANOABACTERIA RED ALGAE GREEN ALGAE, HIGHER PLANTS BUT CAREFUL…

  13. BUT CAREFUL… Determination of Fm is very difficult in red algae due to phycobilisome movement  application of far-red pulse before measurement to ensure that PSII antenna is associated to PSII

  14. BUT CAREFUL… Campbellet al. (1998)

More Related