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Project Progress

Samples were obtained from three different field sites, to isolate strains of the chlorophyll d utilizing cyanobacterium Acaryochloris marina, and preliminary installations were made at one site to quantify its in situ light environment.

At the Salton Sea, California, where a strain of A. marina was previously discovered and of which Blankenship maintains lab cultures, Kiang made several visits to locate areas where A. marina is actively growing. Kiang partnered with JPL scientists, Simon Hook and Bill Johnson of the ASTER and HyTES missions to install settling plates at their meteorological platform in the Salton Sea in January 2014, to grow biofilms for field and lab measurements of community structure, light spectral transmittance and reflectance, and in situ incident spectral irradiance. Plates were installed at two different depths in the water and successfully grew biofilms. Unfortunately, chemical corrosion by the highly polluted waters caused the installation to disintegrate after 6 months and before the plates could be retrieved. Plans for a hardier installation are in progress.

At Pillar Point, Half Moon Bay, and Moss Beach, California, Kiang and Parenteau collected red algae samples and found evidence of Chl d on a sample of the red macroalga Hymenena flabelligera, through pigment extracts and spectral analysis. After this preliminary survey, another field visit is planned for March 18, 2015, partnering with Dr. Kathy Ann Miller, the Curator of Algae at the University Herbarium at UC Berkeley. Identification of Chl d will be done by HPLC in the labs of Blankenship and Hoehler, and enrichments for far-red cyanobacteria done in the labs of Blankenship and Parenteau.

At Cuatro Cienegas Bolson, Mexico, the Early Earth analogue site of Siefert, water and sediment samples were taken from a Laguna intermedia. Gene sequencing of at a Mexican collaborator’s lab produced strong 16S hits for Acaryochloris, which would be the first example of this cyanobacterium in a freshwater environment. Siefert and Mexican collaborators are returning to the site in late February 2015 to collect fresh sample for enrichments of live cultures, to be conducted in the lab of Blankenship.

Kiang published a white paper exploring theoretical challenges in quantifying the long wavelength limit of oxygenic photoysynthesis in a special issue on Astrobiology in The Biochemist magazine.