Lane, T. w. Dept. of Geosciences, Princeton University, tlane@princeton.EDU
Morel, F. w. Dept. of Geosciences, Princeton University, Morel@geo.princeton.EDU
THE ROLE OF CADMIUM IN CARBON ACQUISITION IN THE MARINE DIATOM THALASSIOSIRA WEISSFLOGII
The low availability of a variety of metals can place a limitation on productivity in many marine environments. We are presently examining the strategies that organisms have evolved to compensate for some forms of metal limitation. Carbonic anhydrase (CA) constitutes the major use of intracellular Zn in a number of diatom species including our model organism, Thalassiosira weissflogii. At low Zn concentration the ability of T. weissflogii to utilize HCO3- is impaired and consequently the growth rate is limited at low PCO2. Work from our lab has indicated that Cd can also compensate for Zn limitation in T.weissflogii . Addition of Cd to Zn limited cultures of T. weissflogii enhances the growth rate at low PCO2, although the levels of the major Zn requiring CA, TWCA1, remain low. These cultures express a novel, Cd specific, CA . We have carried out initial characterizations of the regulation of the Cd-CA and have been successful in purifying this Cd-CA by standard chromatographic and electrophoretic techniques and have further demonstrated that it is indeed distinct from TWCA1. We are now cloning the cDNA encoding the Cd-CA. The characterization, isolation, and cloning of the Cd specific CA will be discussed.
Day: Thursday, Feb. 4
Time: 04:45 - 05:00pm
Location: Sweeney Center