Science in the First Person: Al Place on making vegetarians of farmed fish

Researchers have produced one of the most complete and detailed genetic maps ever created for a dinoflagellate — a group of microscopic algae that play essential roles in marine food webs and global ecosystem health. The new genome for Amphidinium carterae sheds light on how these tiny organisms organize and control their genes, challenging long-held assumptions about their massive and complex DNA.

Dinoflagellate genomes are far larger and more repetitive than those of most other organisms, making them challenging to study. Using innovative long-read DNA sequencing technology from Oxford Nanopore, the research team assembled a near-complete 1.25 billion–base-pair genome and mapped its genes with a high level of accuracy. 

A group scientists have used new genetic sequencing data to understand how an ancient organism that lived alongside the dinosaurs has evolved over millions of years. A four-year effort by a genetic research team from a dozen universities has uncovered for the first time the biology and evolution of dinoflagellates, tiny but complex organisms primarily known as marine plankton.

About half of atmospheric carbon dioxide is fixed by ocean's phytoplankton, mainly picocyanobacteria, through a process called photosynthesis. Picocyanobacteria are tiny, unicellular microorganisms that are abundant and widely distributed in freshwater and marine environments. A large portion of biologically fixed carbon is formed by picocyanobacteria at the sea surface and then transported to the deep ocean.

What remains a mystery is how colored dissolved organic matter which originates from plant detritus (either on land or at sea) makes it into the deep ocean. A team of scientists from the University of Maryland Center for Environmental Science and around the world potentially found a viable marine source of this colored material.