Characterization of a novel carbohydrate binding domain of a putative amylase

NICOLAS HEDIN; JULIETA BARCHIESI; DIEGO GOMEZ-CASATI; MA. VICTORIA BUSI

Mar del Plata

Congreso; LI Congreso Anual de la Sociedad Argentina de Investigación Bioquímica y Biología Molecular; 2015

Starch Binding Domains (SBD) are one type of carbohydrate binding domains (CBM) that have acquired the evolutionary advantage of being able to interact and disrupt the substrate surface on a particular way. This can be accomplished because this SBD present two polysaccharide binding sites. The proteins containing these CBMs show a strong physical association with the different substrates, increasing the rate of enzymatic reactions. These modules occur both in catalytic and also in non-catalytic proteins, constituting acore from which the catalytic proteins are organized, in the latter. We decide to study the starch metabolism of the picoeukaryote Ostreococcus tauri because even it has a small genome, this pathway maintain a complexity similar to Arabidopsis thaliana. In the present work, we characterized a predicted CBM20 containing amylase of Ostreococcus tauri. We propose a possible molecular structure using bioinformatics modelling technics, and we analyze the binding capabilities of this module to different insoluble substrates. The results suggest that this particular CBM has a high affinity for linear polysaccharides.