CHYMOTRYPSIN INTERACTION WITH POLYANIONS: THERMODYNAMICS, SOLUBILITY AND SIZE OF THE COMPLEXES

GUILLERMO PICÓ; NADIA WOITOVICH VALETTI; LAURA CAPPELLA; JULIA LOMBARDI; VALERIA BOERIS

Laussane

Congreso; International Symposio of Polyelectrolytes; 2012

Ecole Polytenic de Lausanne

The complex formation between chymotrypsin (ChTRP), a basic protein, and the following polyanions: carragenane (Carr), polyvinylsulphonate (PVS), polyacrilate (PAA), Eudragit S100 (EuS) and L100 (EuL) was studied by turbidimetry, dynamic light scattering (DLS) and isothermal titration calorimetry (ITC). Thermodynamical thermal stability of the enzyme was also assayed. The net positive electrical charge of the protein is partially neutralized by the negative electrical charges of the different polyelectrolytes (PEL). The differences in the structure of the PEL, such as rigidity, molecular weight (MW), lineal charge density and acidity are related to the pH range of solubility, the stoichiometry of interaction and the size of the soluble complexes and non-soluble macroaggregates.