Research

Cell free biosynthesis of platform chemicals from waste


wasteIn the last decades microbial biotransformation has replaced costly and difficult chemical synthesis of a wide range of chemicals. Metabolic engineering of microbial hosts, however is a time consuming, laborious and highly complex task. Major challenges such as high substrate costs, cell viability and product toxicity limit the possibilities of in vivo metabolic engineering. A cell free approach of the conversion from natural feedstocks via selected biocatalysts has the potential to become a powerful strategy in tackling the increasing demand of bulk and speciality chemicals. By heterologous expression of selected or engineered enzymes, near-endless combinations of highly efficient biosynthetic routes are possible. In our lab we isolate, characterize and immobilise novel enzymes, for the assembly of efficient production pathways for useful chemicals. Years of extensive research on cellulytic and hemicellulytic enzymes aid to break down complex sugars from various waste compounds. These sugar monomers are being converted by nearly theoretical yield into desired valuable compounds.

 

View our poster for the  “Extremophiles 2016” here.

 

Development of protein-based nanocompartments for drug delivery


Compartmentalisation is an important organisational feature of life that allows otherwise incompatible biochemical processes to function cohesively within a cell. It occurs at varying levels of complexity, from eukaryotic organelles and bacterial microcompartments, to viral capsids and even the molecular reaction chambers formed by enzyme assemblies. Encapsulins are a newly reported class of protein-based nanocompartments produced in bacteria and archaea. They are typically composed of multiple copies of a single protein subunit, which self-assemble with precision to form hollow cage-like nanostructures that are uniform in composition, size and morphology. Encapsulins have been recently used to encapsulate foreign cargo, such as recombinant proteins and inorganics. In addition, the external and internal surfaces of these nanocompartments can be easily genetically engineered to display short peptide sequences (e.g. epitopes for vaccines, peptide-based drugs, and antimicrobial peptides) that can further enhance their functionality. Accordingly, encapsulins represent a promising alternative to the lipid, polymer, and inorganic-based compartments that are currently used as vehicles for the encapsulation and targeted delivery of therapeutics. This project will use synthetic biological techniques to modify encapsulins that can be loaded with a drug and then upon reaching their biological target be activated to disassemble and release the drug, thus providing both spatial and temporal control of drug delivery in vivo.

 

Production of bioactive compounds from paramylon


facs_fig_webParamylon is a storage polysaccharide produced by the flagellated protist Euglena gracilis. It is a high-weight polymer consisting of β-(1,3)-D-glucan units deposited as granules in the cytoplasm of E. gracilis. β-1,3-glucans have been reported to display bioactivity in mammals depending on their chain length, including anticholesterol, immunostimulating, antiinflammatory, antimicrobial, antitumor, hepatoprotective, antidiabetic and antihypoglycemic activities, making them ideal candidates for nutraceuticals. Although the structure of paramylon is not complex, little is known about the mechanism of its degradation via enzymatic hydrolysis. We are trying to elucidate the enzymatic degradation pathway of paramylon to facilitate the biotechnological production of bioactive health-enhancing compounds by developing a high-throughput screening system for paramylon-degrading enzymes using fluorescence-activated cell sorting (FACS).

View our poster for the  ““Advances in Biotechnology for Food and Medical Applications” 2016 workshop ” here.