Sarah Tian ’18



Project Title

A Biological Role for Vanadium in Cyanobacteria

During my internship, I grew cultures of the cyanobacterium Anabaena variabilis in media containing either molybdenum, vanadium, or both. The purpose of this project was to analyze the metal intake by the cyanobacteria and to study possible uses for vanadium in cyanobacteria. I grew the bacteria under both nitrogen fixing and non-nitrogen fixing conditions to see whether or not vanadium was solely being used for this N-fixation process and to determine if the amount of metal taken in by the cells varied. Trace metals like vanadium play important roles in catalyzing processes of biogeochemical importance; despite this, vanadium is rather understudied. I found that when the bacteria were given a source of nitrogen in the media, they took up less metal in general, but there was a much larger decrease in the amount of molybdenum taken up, not the amount of vanadium. This suggests that there are uses for vanadium in cyanobacteria and future study is warranted. I learned how to conduct independent work and how to think critically about conducting research and running my own experiments. I hope that I can both use and build on these skills in future areas of study as I progress towards my junior independent work and senior thesis.

Internship Year


Project Category

Climate Change and Environmental Science


Morel Laboratory, Geosciences Department, Princeton University, Princeton, NJ


François Morel, Professor, Geosciences