Characterization of SdAmy, a novel alpha amylase from Saccharophagus degradans

WAYLLACE, NATAEL M.; PERALTA, DIEGO A.; CLAVIJO, M.F.; BUSI, MARIA VICTORIA; DIEGO FABIAN GOMEZ CASATI

Virtual

Congreso; 3er. Encuentro & 1er. Workshop, Red Argentina de Tecnología Enzimática (RedTez).; 2021

RedTez

Saccharophagus degradans is a gram-negativemarine bacterium. It is the most versatile bacterium in terms of thedegradation of complex polymers (CP) found to date. The high rate ofdegradation of different polysaccharides that this bacterium has makes it acandidate to obtain and investigate the properties of the enzymes that degradethese polymers. The objective of this work is to carry out the structuralcharacterization of SdAmy, a novel alpha-amylase from S. degradans, and the study of the CBM20 domain of SdAmy. Theenzyme is composed mainly by a N-terminal catalytic domain (CD), a centralAamyC domain (AamyC) and a carbohydrate-binding module family 20 at theC-terminal (CBM20). SdAmy and the CBM20 domain was successfully expressed in Escherichia coli cells, purified and itsproperties were investigated. The enzyme showed maximum activity at 40°C and pH5.0. SdAmy showed a Vmaxand Km values of about 0,04UA.μg-1.min-1 and 0,34 g.l-1 , respectively,when used potato starch as substrate. The activity and stability of SdAmy wasimproved in the presence of calcium. Carbohydrate binding assays showed that theCBM20 domain bind to amylose with a Kadof 3.13 ± 0.25 ml/g. Our results allow us to propose that this novel SdAmy asan alternative amylase that could be used in processes involving enzymes thatact at moderate temperatures.