ESSI seminar - Nick Hawco

Nick Hawco, University of Hawai'i

‘Cobalt Scarcity in the Open Ocean’

For our first ESSI Seminar of 2022 we are delighted to (virtually) welcome Nick Hawco from the University of Hawai’i.

Register to attend here.

Abstract: Society looks to the ocean floor as a bountiful source of cobalt to power smartphones, electric car batteries, and many other green technologies. Yet the oceans themselves are largely devoid of this metal: less than 1 in every trillion molecules of seawater contains a cobalt atom, and fewer still would be recognizable to microbial transporters seeking to acquire Co2+ to power key metalloenzymes. In this seminar, I will present an updated picture of the global cobalt cycle, refined by thousands of new measurements collected from the international GEOTRACES program. I'll also describe culture experiments aimed at quantifying the cobalt requirement of the abundant cyanobacterium Prochlorococcus, whose photosynthesis serves as the foundation for open ocean food webs. Despite maintaining growth with just a few dozen cobalt atoms per cell, wild Prochlorococcus populations may be close to cobalt limitation thresholds, especially in the South Pacific Ocean.