My research within the subject photosynthesis currently has developed into two different projects: 1. Investigating the potential of Nordic microalgae for wastewater reclamation and biomass generation and 2. Finding the function of plant proteases. Research objects in my group range from cyanobacteria, via green microalgae and cryptomonad algae to higher plants.

Wastewater reclamation and biomass generation by Nordic microalgae

With the expanding human population, we will need more food, more fuel and more water. At the same time, we have to reduce CO2 emissions by over 80%. One approach to address this problem is to recycle CO2 for fuel- or chemical-production using photosynthesis. Photosynthetic organisms use solar energy to incorporate atmospheric CO2 into organic molecules. We let microalgae perform photosynthesis and at the same time clean municipal and industrial wastewater. The algal biomass then can be used for biofuel, biogas, biofertilizer or even bioplastic. Our challenge is the sub-arctic climate we have in Northern Sweden with low temperatures and short-day lengths. Therefore, we investigate the potential of local, natural algal strains. We test their performance in cleaning wastewater, analyze their biomass and investigate, how to prolong their growth phase.

Plant proteases

Proteases are proteins that break down other proteins. They are involved in many different biological functions, e.g. the digestion of our food, cleaning the cell from malfunctioning proteins or cell signaling. Even though hundreds of proteases are encoded in the genomes of various plants, their biological roles are mostly unknown. Using molecular biological and biochemical methods, we try to find identify the function of some of them. Metacaspases, for example, are proteases thought to be involved in programmed cell death (PCD), the genetically encoded process leading to suicide of specific cells or tissues. In single-cell algae and cyanobacteria the necessity for PCD is less obvious, still these microorganisms contain metacaspases. The aim of our research is to investigate the broad network of PCD in photosynthetic single-cell organisms and at the same time to perform detailed functional, structural and evolutionary studies of the metacaspase homologues.

A) Various green microalgae found in municipal wastewater; B) Scanning electron microscope (SEM) image of the green microalga C. vulgaris 13-1 and its symbiotic bacterium Rhizobium sp. at 50 K magnification (Photos: Lorenza Ferro); C) Electron microscopy image of the cyanobacterium Synechocystis sp. 6803 (Photo: Tania Tibiletti); D) Chlorophyll fluorescence emitted from Arabidopsis thaliana leaves (Photo: Laxmi Mishra)

Svensk sammanfattning