1 / 24

Schedule of Activities Session Two

Red Layer Microbial Observatory Biology 507 - In-Lab Workshop Photosynthetic Microbes from Local Rivers & Beyond. Schedule of Activities Session Two. Photosynthesis, Pigments, Archaea Pigment Analysis Set-Up Follow-Up - Last Week Curriculum Discussion/Essay

missy
Download Presentation

Schedule of Activities Session Two

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. Red Layer Microbial ObservatoryBiology 507 - In-Lab WorkshopPhotosynthetic Microbes from Local Rivers & Beyond

  2. Schedule of Activities Session Two • Photosynthesis, Pigments, Archaea • Pigment Analysis Set-Up • Follow-Up - Last Week • Curriculum Discussion/Essay • We may or may not have time for each person to use the fluorescence microscope.

  3. Photosynthetic Pigments Location Specific proteins hold in membrane - nonpolar Species-specific proteins define real absorption Naked pigment uses discrete value - e.g. 770 Species-specific proteins alter - e.g. 800, 900 Different methods for naked vs. protein-bound

  4. Chlorophylls (Chl) - Oxygenic Plants - green a and b Algae - green a/b, gold/brown a/c, red a/d Cyanobacteria - green a only All of these, when excited by UV, “fluoresce” or emit light in the red or yellow range.

  5. Accessory Pigments - Oxygenic Carotenes - yellow or red, WIDESPREAD Xanthophylls (brown), phycoerythrin (red)

  6. Bacteriochlorophylls (Bchl) - Anoxygenic Purple bacteria - Bchl a Green bacteria - Bchl c Heliobacteria - Bchl g

  7. Accessory Pigments - Anoxygenic Carotenes - yellow or red, WIDESPREAD Phycocyanin - blue, similar to phycoerythrin Many chemotrophic pathogens have carotenes because these neutralize H2O2.

  8. Isolating Naked Pigments Because nonpolar, organic solvents involved Methanol for research-grade work - GLOVES Acetone acceptable/available - harsh Because cell walls, you will pulverize sample Petroleum ether (jar/hood) - chromatography Data useful for major grouping assignments A spectrophotometer allows one to skip chromatography.

  9. Isolating Protein/Pigments IN Membrane Disrupt cells using just pulverization - expensive Fragmented pigments called “in vivo” Data useful for grouping and species variation

  10. Archaeal “Photosynthesis” - Class By ItselfRemarkably, these are commercially available. Why Unique? Bacteriorhodopsin (Brho) pigment in membrane Light causes Brho to physically move H+ out This generates proton motive force - ATPase NO ETC involved in this process Brho homologous to eukaryotic rhodopsin.

  11. Halophiles 5.5+ M salt - many different ions and pH Evaporation ponds, salt lakes, salted foods Halobacterium = phototropic halophile Many other Halophiles are not photosynthetic. They are simple chemotrophs.

  12. Photosynthesis and Evolution Hot earth and the purple origin theory Ancient earth - 100°C but dark Heat gives off infrared - 900 nm or more Emerging purple Bchl absorb this Human eyes and salty Archaea - speculate all you want.

  13. What does the tree of life support? Green nonsulfur most ancient - purple members Phototrophy evolved many times Chloroplast most similar to Cyanobacteria

  14. Pigment Analysis Set-Up Overview Each team will set up 2-3 different phototrophs You will pulverize the sample in methanol Extract 15 minutes - ice/dark Then streak on chromatography paper, develop And analyze the rest on a spectrophotometer Share class data - need all for web analysis Analyze fluorescence data on web template.

More Related