Bioprospecting of Trichococcus species

Promovendus mr. N (Nikolaos) Strepis MSc
Promotor Fons AJM (Fons) Stams
Copromotor DZ (Diana) Machado de Sousa PhD MSc
dr. PJ (Peter) Schaap
Organisatie Wageningen University, Systems and Synthetic Biology, Laboratory of Microbiology

wo 16 januari 2019 16:00 tot 17:30

Locatie Aula, gebouwnummer 362

Samenvatting (Engelstalig)

Since 1928 with the discovery of penicillin, the value of microbes in our society was reconsidered significantly. Nowadays, 60% of commercial drugs and products mimic or derive from microbial metabolites. After almost a century, can we find new compounds and if so; where? For addressing this question, we need a large-scale screening of the microbial capabilities. Trichococcus species have multiple genes for producing 1,3-propanediol (1,3-PDO), which synthesizes the partially biodegradable plastic PTT. Based on this, we developed a strategy for analyzing 90,000 bacterial genomes that eventually generated information for every microbial characteristic. The outstanding factor is that all this information is stored in a database that can be easily mined for everything. This collective and unbiased strategy resulted in identifying the key genes for efficient production of 1,3-PDO. We discovered 187 novel candidates that can produce 1,3-PDO and some were confirmed in the lab.

Another result of the screening was about Trichococcus patagoniensis. This bacterium grows in minus 5 degrees without oxygen and was discovered by NASA scientists to simulate life in other planets. When it is cold and without oxygen, T. patagoniensis “extra-terrestrial” properties allow it to create its own ”blanket” by producing exopolymer saccharides. We characterized this cryoprotectant compound as inulin, which prevents crystallization of water and many plants use it for preserving their roots in subzero temperatures. Furthermore, inulin is a commercial prebiotic and is connected with gut health. Considering the bacterial kingdom, there are limited members producing inulin and none of them were identified as prychrotolerant species. T. patagoniensisis produces plenty of inulin and due to its robustness, easily can be the next biofactory for the compound.

The applied methods in this PhD thesis is a platform for mining every bacterial or metabolic information. All the knowledge is there and we need to dive into it. Every finding will be revolutionary and expand our perspective for microbes. Big data mining is like Zenos Dichotomy paradox, we will always know half and never everything.