Uncovering the Extreme: Proteins for Biotechnology

Metagenomic data represents a vast and largely untapped reservoir of novel enzymes with transformative potential for biotechnology. By enabling the discovery of new genetic information without needing to culture source organisms, metagenomics has revealed immense sequence diversity. This is especially evident in extreme
environments where organisms and their enzymes are adapted to harsh conditions of temperature, pressure, salinity or pH. Such enzymes are highly attractive for biotechnology, where robustness under diverse chemical conditions is essential.

The Virus X project explored this diversity to generate innovative products for biotechnology and industry. From their database of over 50 million genes, eleven encoding single-stranded DNA binding proteins were selected for investigation. Ten were expressed and purified with sufficient yield and purity for analysis, and six were
fully characterised using analytical size exclusion chromatography, thermal shift assays, and electrophoretic mobility shift assays. Several proteins also enhanced diagnostic applications. Notably, UvsXt increased the sensitivity of loop-mediated isothermal amplification ten-fold while others reduced false positives.

Additional enzymes with biotechnological promise were also investigated. Two clostripain-like proteases were studied with collaborators at the University of Bergen. Structural modelling of one, globupain, suggested conformation changes during autoproteolytic activation, while promising crystallisation conditions were identified
for the second protease. A novel ulvan lyase, Wf-PL40-V, was also determined to a resolution of 1.4 Å (R/Rfree 0.15/0.18). Unlike previously known single-domain ulvan lyases, Wf-PL40-V comprises two domains and shows greater structural similarity to alginate lyases and heparinases.

Together, these findings highlight the value of extremophilic enzymes for commercialisation. They also serve as tools to advance fundamental understanding of sequence-structure-function relationships in extremophilic proteins.