Team:ECUST China/Demonstrate
Our Proposal
As the idea of sustainable development prevails, paper recycling campaigns have been gaining momentum. Numerous paper mills have put waste paper into reuse, attempting to cut the cost. The paper fiber, nevertheless, cannot be recycled infinitely because of keratinization during pulp-beating, and those broken short fibers are discarded in each round of recycling process. Our Paper-transformer is capable of transforming these TRASH into TREASURE!
TRASH Degradation
We have equipped the our chasis organism—E.coli—with three types of cellulase—β-glycosidase, endoglucanase, exoglucanase, encoded by gene cep94A, cenA, cex respectively, which work as a whole to facilitate the host bacterium to degrade cellulose into glucose. Yet we didn’t fantasize the glucose could accumulate gradually as a stable intermediate without being utilized by the host cell, given its ready availability as energy source beyond others. So we decided to stop at cellobiose, a disaccharide produced from cellulose by exoglucanase and endoglucanase combine and catalyzed into glucose by β-glycosidase. secretion strategies: α-heomolysin system(hlyABD).
TREASURE Accumulation
We have also imparted the our chasis organism—E.coli—with cellulose synthase and its accessory proteins, encoded by gene acsAB, acsC and acsD respectively.
Inverter-- trash to treasure
Since cellulase and cellulose synthase function as a pair of antagonists, consuming each other’s product and build their own, it is pivotal to prevent this futile and relentless competition from happening. Thus, we designed an inverter, a duel plasmid system which is compatible in the DH5α host cell, to separate the degradation of cellulose from accumulation of Bacterial cellulose, and to regulate the timely expression of related genes.
Scope beyond paper industry!
textile industry, cosmetic industry, medical use, etc.
