Pigments and Physiology of Cyanobacterial Mats that are Modern Analogs of Life on Early Earth
Presentation Type
Oral and/or Visual Presentation
Presenter Major(s)
Biology
Mentor Information
Bopi Biddanda
Department
Annis Water Resource Institute (AWRI)
Location
Kirkhof Center 2266
Start Date
10-4-2013 12:00 AM
End Date
10-4-2013 12:00 AM
Keywords
Environment, Life Science, Physical Science
Abstract
Recently discovered submerged sinkholes in Lake Huron are low-oxygen, high-sulfur extreme environments for microbial life. My work investigates the pigments and photophysiology of the cyanobacteria dominated mats present in these sinkholes under in situ and lab studies to understand acclimation to light treatments. Mats were grown in varying light intensities and photosynthetic inhibitors and examined for pigment composition and photosynthetic efficiency using PAM fluorescence to provide insight about light adaptive capabilities and use of oxygenic and anoxygenic photosynthesis. In situ observations show seasonality in photosynthetic efficiency for all sites throughout the year. Lab results indicate a 1-2 day photoacclimation period after which yield stabilizes and increased light intensity treatments result in increased photosynthetic efficiency. Inhibitor studies reveal that DCMU, a photosystem II inhibitor, significantly halted photosystem II activity, while NaH2S had no effect.
Pigments and Physiology of Cyanobacterial Mats that are Modern Analogs of Life on Early Earth
Kirkhof Center 2266
Recently discovered submerged sinkholes in Lake Huron are low-oxygen, high-sulfur extreme environments for microbial life. My work investigates the pigments and photophysiology of the cyanobacteria dominated mats present in these sinkholes under in situ and lab studies to understand acclimation to light treatments. Mats were grown in varying light intensities and photosynthetic inhibitors and examined for pigment composition and photosynthetic efficiency using PAM fluorescence to provide insight about light adaptive capabilities and use of oxygenic and anoxygenic photosynthesis. In situ observations show seasonality in photosynthetic efficiency for all sites throughout the year. Lab results indicate a 1-2 day photoacclimation period after which yield stabilizes and increased light intensity treatments result in increased photosynthetic efficiency. Inhibitor studies reveal that DCMU, a photosystem II inhibitor, significantly halted photosystem II activity, while NaH2S had no effect.