UC Davis UC Davis Previously Published Works Title An experimental study of magnesium-isotope fractionation in chlorophyll-a photosynthesis Permalink https://escholarship.org/uc/item/8x5346hj Journal Geochimica et Cosmochimica Acta, 70(16) ISSN 0016-7037 Authors Black, J R Yin, Q Z Casey, W H Publication Date 2006-08-01 Peer reviewed eScholarship.org Powered by the California Digital Library University of California Geochim. Cosmochim Acta June 07,2006 An Experimental Study of Magnesium-Isotope Fractionation in Chlorophyll-a Photosynthesis Jay R. Black Department of Chemistry Department of Geology, University of California, Davis, CA 95616.
[email protected] Qing-zhu Yin Department of Geology, University of California, Davis, CA 95616.
[email protected] and William H. Casey* Department of Chemistry Department of Geology, University of California, Davis, CA 95616.
[email protected] keywords: photosynthesis, magnesium isotopes, isotope fractionation, chlorophyll, cyanobacteria, biogeochemistry running title: Mg-isotope fractionation in chlorophyll-a 1 Abstract Measurements are presented of the magnesium isotopic composition of chlorophyll-a, extracted from cyanobacteria, relative to the isotopic composition of the culture medium in which the cyanobacteria were grown. Yields of 50-93% chlorophyll-a were achieved from the pigment extracts of Synechococcus elongatus, a unicellular cyanobacteria. This material was then digested using concentrated nitric acid to extract magnesium. Separation was accomplished using columns of cation-exchange