Recombinant proteins are an integrated part of our daily lives – they are in the laundry powder, hair dyes, our food and medicine. In recent years much research has gone into using microalgae as expression hosts. Chlamydomonas reinhardtii is an eukaryotic microalga that has been shown to produce e.g. monoclonal antibodies that are useful in cancer treatment. This kind of protein cannot be produced by conventional hosts (e.g. E. coli). Unfortunately production in microalgae is rarely cost efficient. One reason for this is cultivation issues.

Compared to bacterial or fungal hosts, C. reinhardtii grows only to relatively low densities in bioreactors. This is because it relies on sun light for photosynthesis and cannot grow on organic carbon sources such as sugar. As the density in a culture increases the light cannot reach the center and the algae will lack energy to grow. By supplying a reduced carbon source (acetate) this problem can be alleviated, but acetate affects the pH and thus must be continuously titrated into the culture.

Your project

This project aims at making the green algae C. reinhardtii a more attractive production host in the biotech industry. The objective is to enable C. reinhardtii to grow on common sugars such as glucose and sucrose. The reason C. reinhardtii cannot grow on sugars is primarily due to its lack of sugar importers in the plasma membrane.

You will engineer selected sugar transporters from both other algae species and Arabidopsis thaliana into C. reinhardtii and investigate changes in uptake of and growth on common sugars.

Learning outcome

At the end of this project you will be able to:

• Design expression constructs in silico, perform USER cloning and validate cloned sequences
• Extract gDNA from plant + algae tissue and plasmids from E. coli
• Transform the nuclear genome of C. reinhardtii
• Validate protein expression by targeted proteomics (SRM)
• Set up small scale cultivation of algae and investigate changes in sugar metabolism
• Establish uptake assays with fluorescent sugar analogs to study transporter activity
• And finally, you will be introduced to flow cytometry and learn to analyze the data output

The project provides a solid foundation for future work in both research labs and biotech industry, gives a solid foundation in basic skills used in molecular biology and an understanding of necessary bioinformatics tools.  

Who we are; Transport group of Hussam H. Nour-Eldin in the National Research Centre of Excellence, DynaMo (https://dynamo.ku.dk/). We provide a stimulating, international research environment where you have an execellent opportunity to advance your skills. Our research lab has a strong international research profile with a record of high impact publications