BUILDING THE MOLECULAR BLOCKS OF MULTI-ENZYMATIC COMPLEXES FOR THE IMPROVEMENT OF BIOFUEL PRODUCTION

NATALIA GOROJOVSKY; MATÍAS IGLESIAS PANDO; JAVIER SANTOS; MARTÍN DODES TRAIAN; VANESA ZYLBERMAN; FERNANDO GOLDBAUM; PATRICIO CRAIG

Buenos Aires

Congreso; II Reunión Conjunta de Sociedades de Biociencias; 2017

The enzymatic degradation of lignocellulose generates sugars thatupon fermentation produce bioethanol. The enzymes currently usedin this process are expensive and have low efficiency. It is importantto develop new methods to increase their activity and stability for aneconomically viable production of bioethanol.Cellulosomes are multienzymatic complexes that colocalize different cellulolytic enzymes and cellulose binding domains, increasingtheir degradation activity through enzymatic proximity and substratetargeting effects. However, the industrial production of natural cellulosomes has serious limitations because of the properties of theirscaffolding protein. Our goal is to use the structure of an oligomericprotein that is highly stable and highly expressed in bacteria, as ascaffold for the colocalization of a consortium of cellulolytic enzymesand the development of artificial cellulosomes. For the assemblyof these multienzymatic particles we use a non-covalent couplingstrategy trough high affinity heterodimeric peptides complementaryfused to the oligomeric scaffold and the target enzymes. For thispurpose we cloned and expressed in E.Coli the catalytic domainof a variety of enzymes, including endoglucanases, exoglucanases,xylanases, beta glucosidases and cellulose binding domains fromdifferent organisms, fused to the coupling peptide. The amount andsolubility of these multienzyme building blocks were compared tothe original isolated domains. The coupling peptide doesn?t perturbthe solubility of the target proteins. At least one member of eachfunctional category is solubly expressed in significant amounts, encouraging further development of the artificial cellulosomes.It is expected that these complexes will help to increase the enzymatic lignocellulose degradation, reducing the cost of bioethanolproduction and favoring fossil fuels substitution