Hydrolase discovery in the extremophile Galdieria

Galdieria is a red alga that exhibits metabolic versatility and displays enormous capacity to thrive
at highly acidic conditions (down to pH 0) and temperatures above 55C, the theoretical limit of
eukaryotic life. Members in this genus display broad metabolic repertoires allowing vigorous
growth on virtually any sugar, sugar-alcohol or organic-acid source and it is capable of both
photoautotrophic and chemoheterotrophic growth. Galdieria is a metabolic workhorse. The
extremophile lifestyle of Galdieria makes it a fascinating organism to find those novel species with
properties that have industrial biotechnological (IB) applications. To exploit Galdieria for use in the
IB sector, we must define the constellation of diversity in metabolic capacity it displays. In phase 1
of this project, the student will perform phylogenomic discoveries of IB-relevant enzymes. From
there, annotation leads to a description of metabolic predictions using the innovative pipeline that
exploits genome-scale metabolic networks. In phase 2, informatic descriptions will be produced of
excreted enzymes that can function under very low pH and elevated temperature. From the large
diversity of classified enzymes, homology searches will be used to identify xylanases and other
cellulases, proteases and oxidative enzymes. In phase 3, the student will perform enzyme
characterisation and develop information on process-production performance to a pre-industrial
scale-up. By definition, all identified enzymes must function at high temperature and very low pH.
Thus these will be the most heat- and acid-resistant enzymes ever isolated from a eukaryote,
given that Galdieria lives at the absolute limits of eukaryotic life.