Peninsula are dying off as the water warms, and others, not seen before there, are moving in. If Bhattacharya and Schofield can sequence the genomes of those algae cell by cell, as he and
Stepanauskas have done with picobilophytes, they might learn much more about how climate change has affected the ecosystem in that region. Bigelow Laboratory's Single Cell Genomics Center, established by Stepanauskas and his colleagues, has analyzed more than150,000 individual microbial cells, shedding new light on the invisible majority of our planets biological diversity.
When picobilophytes were discovered in 2007, scientists believed they were photosynthetic that is, that, like green plants, they converted carbon dioxide into food, using energy from sunlight. But these tiny cells have been impossible to culture in the laboratory and this may have been because they were starving, deprived of their natural food sources.
For this project, the scientists hauled 50 milliliters (a handful) of seawater out of Boothbay Harbor in Maine, the home of the Bigelow Laboratory. They used a technique called fluorescence activated cell sorting to separate photosynthetic from non-photosynthetic (heterotrophic) cells. They were surprised to find that picobilophytes lacked chlorophyll. They sequenced the genomes of three picobilophytes and were excited to find, in one of them, a new virus, whose circular genome they were able to reconstruct. They were also able to identify and sequence the DNA of creatures the picobilophytes had presumably eaten.
For a marine biologist like Bhattacharya, however, the immediate prospects in his own field hold the most promise. "There is a lot of uncharted biodiversity on our planet that we can't get a hold of because we can't cultivate the cells," he said. "Now, if you can reconstruct the nuclear genomes of individual cells in a sample of seawater, you can begin to infer not only the numbers and kinds
|Contact: Robin Lally|