Pavel Dvorak

I received my PhD degree in Molecular and Cell Biology from the Masaryk University (Brno, Czech Republic) in 2014. My PhD project was focused on development of a knowledge-based strategy for rational optimization of synthetic biodegradation pathway in vitro, in form of immobilized enzymes, and in vivo, in heterologous bacterial host, namely Escherichia coli. My motivation for postdoctoral stay in laboratory of Víctor de Lorenzo stemmed from a desire to deepen my expertise in the fields of Metabolic Engineering and Synthetic Biology, employed for rational engineering of microbial hosts toward specific biotechnological tasks and in-depth understanding of bacterial cell functioning.

My main project at Víctor’s lab aims at constructing a robust P. putida cell factory, displaying self-assembled designer cellulosomes, capable of growing on cellulosic waste and transforming the lignocellulose-derived sugars into acetyl-CoA and value-added chemicals. Up to 220 million tonnes of lignocellulosic and cellulosic waste (crop residues, wood waste, paper, or food waste) is available for biotechnological purposes in EU every year. Lignocellulose can be decomposed to cellulose- and hemicellulose-derived monomeric sugars and lignin-derived aromatics that can serve as cheap substrates for production of many VAC. A major obstacle to the wider commercialization of biomass-derived products is the high cost of degradation of raw material into simple glucose and pentoses, which is typically achieved using expensive soluble cellulolytic enzymes. The construction of well-defined recombinant microbes that can degrade biomass and convert it efficiently into VAC without externally added enzymes is a holy grail of biotechnology and an essential step toward so called consolidated bioprocessing.

Scheme_overview of the actions

KT2440 represents a perfect bacterial host of choice for a challenging task sketched above. The strain possess great metabolic versatility and can efficiently cope with diverse exogenous and endogenous stresses, which has recently been proven useful for utilization of cellulose-derived glucose and lignin-derived aromatics for biosynthesis of polyhydroxyalkanoates (PHA), biodegradable polyesters that can substitute oil-derived plastics. Strain KT2440 can utilize glucose via acetyl-CoA and de novo fatty acid biosynthesis for formation of medium chain length PHA, that have better elastomeric properties and wider application potential than short chain length PHA, produced by Ralstonia euthropha or recombinant E. coli. The effort shall lead to the first example of deeply engineered microorganism capable of consolidated bioprocessing of all major components of lignocellulose