Stockholm university

Research project N2-fixing planktonic symbioses:

biogeochemically significant models to study molecular regulation & genomic innovation

Diatoms are one widespread and important group of phytoplankton. Most diatoms reside in coastal waters, while others thrive in nutrient poor waters by forming partnerships, or symbioses, with N2-fixing cyanobacteria. The cyanobacterial symbiont reduces N2 gas into bioavailable N for their hosts, while also fertilizing the surrounding community. This project aims to identify the genetic content, or genome, of the host diatoms for the first time. Genomes are like ‘blue prints’ of a cells’ potential, where content and gene order are a reflection of evolution. The proposed research combines a variety of methods, including single cell technologies so that activity, messages (transcripts), and identity of genes are linked to the partner cells.

The PI for this research project is a Wallenberg Academy Fellow, Rachel Foster, and the research is funded by an external grant of 8 750 000 SEK, from the Knut and Alice Wallenberg Foundation.

 

RF2
A chain of Hemiaulus-Richelia symbioses using blue excitation fluorescence microscopy. The red is the chloroplast of the diatom (Hemiaulus), while the filaments of the N2 fixing symbiont (Richelia) fluoresce yellow. The larger coccoid cells on the ends of the symbiont filaments are the heterocysts, or the cite of N2 fixation.

Project members

Project managers

Rachel Ann Foster

Professor

Department of Ecology, Environment and Plant Sciences
Dr. Rachel A Foster, Researcher

Members

Elina Viinamäki

Research engineer

Department of Environmental Science
Elina Viinamäki

Sepehr Bardi

Doktorand

Department of Ecology, Environment and Plant Sciences
Sepehr Bardi, PhD student at SU (DEEP)

Linnéa Ström

PhD

Department of Ecology, Environment and Plant Sciences

Vesna Grujcic

Postdoctoral researcher

Department of Ecology, Environment and Plant Sciences
Vesna Grujcic

Publications