Worden attended Wellesley College, where she received a Bachelor in history, and performed a concentration in earth atmospheric and planetary science coursework at the Massachusetts Institute of Technology. At the latter she worked in the laboratories of John M. Edmond, Reginald Newell and Sallie West. Chisholm. Worden received her Doctor of Philosophy from the Institute of Ecology, University of Georgia, in 2000.
Worden’s research has focused on the physiology and ecology of picophytoplankton, unicellular organisms that are responsible for a large portion of ocean primary production (photosynthetic uptake of atmospheric Carbon dioxide). Worden’s early work focused on methods development for investigating populations while still in the nature environment and their roles in the carbon cycle, and this theme has continued through her career. During an National Science Foundation postdoctoral fellowship at Scripps Institution of Oceanography Worden was recognized for research that revealed the importance of small eukaryotic phytoplankton known as picoeukaryotes, demonstrating that despite low abundance they had a disproportionately high contribution to picoplanktonic primary production.
A second study by Worden while in the laboratory of Farooq Azam overturned the long running idea that Vibrio cholerae existed primarily attached to copepods in aquatic systems
This was considered important for understanding ecology of this human pathogen and vectors for transmission of infective cells. Worden has pioneered eukaryotic "targeted metagenomics" wherein cells of particular interest are separated from the masses using flow cytometry (on a ship) and genomes are then sequenced from only the cells of greatest interest.
Using this approach Worden and collaborators at the Department of Energy Joint Genome Institute sequenced partial genomes from uncultured eukaryotic algae whilst showing the distribution of these photosynthetic protists in the ocean. Her laboratory also investigates ancestral components of land plants, evolutionary biology and distributions of uncultured taxa and interactions between viruses and phytoplankton host cells.
Worden publishes in the fields of environmental microbiology, evolutionary biology, genome science and oceanography.
Worden started a lab as assistant professor at the Rosenstiel School of Marine and Atmospheric Science in 2004, but left soon thereafter for the United States West Coast. In 2009, Worden was named a scholar of the Canadian Institute for Advanced Research (CIFAR), later becoming a fellow of CIFAR (2011).
