Influence of High Pressure on Bovine Serum Albumin and Its Complex with Dextran Sulfate
Vanda B. Galazka, Dave A. Ledward, Ian G. Sumner, Eric Dickinson
Journal of Agricultural and Food Chemistry
Abstract
High-pressure processing of bovine serum albumin (BSA) solutions (0.1−1 wt % protein, pH 7) has shown decreasing protein surface hydrophobicity with increasing pressure, which is further reduced in the presence of dextran sulfate (DS) (BSA:DS weight ratio of 2:1 and 4:1). The total calorimetric enthalpy ΔH for pure BSA is substantially reduced after treatment at 600 MPa, and both the endothermic peak temperature and the value of ΔH for BSA + DS is reduced under the same treatment conditions. Size exclusion chromatography indicates extensive pressure-induced protein unfolding and aggregation during BSA treatment at 400 MPa. Complexation with polysaccharide at low ionic strength protects the globular protein against pressure-induced aggregation. The loss of the protective effect of DS on addition of electrolyte (0.1 M NaCl) is consistent with the predominantly electrostatic character of the protein−polysaccharide interaction. Keywords: Protein−polysaccharide interaction; high-pressure processing; surface hydrophobicity; protein aggregation; differential scanning calorimetry; size exclusion chromatography
Extracted Claims
5 claims extracted from this paper into the knowledge graph
protein unfolding and aggregation induced by pressure
“Size exclusion chromatography indicates extensive pressure-induced protein unfolding and aggregation during BSA treatment at 400 MPa”
protein−polysaccharide interaction protected the globular protein against pressure-induced aggregation
“Complexation with polysaccharide at low ionic strength protects the globular protein against pressure-induced aggregation”
endothermic peak temperature and ΔH reduced under same treatment conditions
“both the endothermic peak temperature and the value of ΔH for BSA + DS is reduced under the same treatment conditions”