Dr. Anna Joëlle Ruff | RWTH Aachen | ABBt - Biotechnology

Tailored biocatalysts for a sustainable bioeconomy are the area of research of Anna Joëlle Ruff. Rational and evolutive protein design help to develop enzymes that perform under the conditions in chemical industry. One focus are enzymes that recover valuable substances from agricultural residues.

Anna Joëlle Ruff studied biology at RWTH Aachen University, focusing on microbiology and biotechnology. In her diploma thesis at the Institute of Microbiology in 2009 she analyzed the glutathione metabolism of fission yeast. Subsequently she was offered the possibility to do her PhD with Prof. Schwaneberg at the Chair of Biotechnology at RWTH Aachen University. During this time she worked on enzyme engineering of monooxygenases in the frame of the EU project Oxygreen.

Monooxygenases incorporate oxygen into their subtrates. They occur in all organisms, playing an important role in degradation of various substances and thereby in detoxification. Furthermore, in plants they have a key role in production of bioactive substances what makes them highly interesting for biotechnology. In the project Oxygreen, monooxygenases were optimized for the production of vitamin precursors. The results were protected in a patent together with the company DSM.

After finishing her PhD (Dr. rer. nat.) in 2012, Anna Joëlle Ruff built up a research group dealing with monooxygenase evolution and development of diversity generation methods. A highlight was the flow cytometry-based high-throughput platform for screening of bacterial monooxygenases which enables screening of millions of enzyme variants in one hour.

Since 2014 Anna Joëlle Ruff leads the division Molecular Bioeconomy at the Chair of Biotechnology at RWTH Aachen University. PhD students, PostDocs and technical assistants form a team of 12 people. In the division, key technologies for directed evolution (promoter toolbox, cepPCR, OmniChange) are developed and used to produce tailored enzymes for a sustainable bioeconomy. A highlight in monooxygenase evolution is the development of whole cell catalysts with an improved diffusion barrier for efficient oxygenation of aromates and terpenes. This was realized in the BioSC project TPOT by coexpression of monooxygenases with a membrane protein which served as a channel. The development of biocatalysts is being continued in the EU projects ROBOX und OXYTRAIN which aim at an extended industrial use of robust oxidative biocatalysts for transformation and production of alcohols.

Another focus of her research is the development of a technology for enzymatic phosphate recovery which would open up the way to new circular value chains. This technology is based on phytases: enzymes that release free phosphate by degrading the phosphate storage molecule phytate which is formed in plants. The use of phytases enables an efficient phosphate recovery from various biological sources, e.g. sugar beet residues from sugar production or rapeseed press cakes from oil production. The obtained phosphate can either be directly utilized in premium fertilizer or can be transformed to valorised food or feed additives by microorganisms.

Anna Joëlle Ruff coordinated various projects she had also co-applied for. She was involved in the BioSC projects P-ENG, PhytaPhos, BioExpresSPro, TPOT, BioSAF und MoRe-Plants. Currently she is involved in the BioSC FocusLab CombiCom.