Evaluation of biological activities, structural and conformational properties of bovine beta- and alpha-trypsin isoforms in aqueous-organic media.

Affiliation

Rosa DP(1), Cruz FT(1), Pereira EV(2), Cicilini MA(3), de Oliveira JS(4), Denadai ÂML(5), Santos AMC(6).
Author information:
(1)Postgraduate at Biochemistry and Immunology, Federal University of Minas Gerais, Belo Horizonte, MG, 31270901, Brazil.
(2)Postgraduate at Biochemistry and Pharmacology, Federal University of Espírito Santo, Vitória, ES, 29047105, Brazil.
(3)Physiological Science Department, Federal University of Espírito Santo, Vitória, ES 29047105, Brazil.
(4)Biochemistry and Immunology Department, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, MG, 31270901, Brazil.
(5)Pharmacy Department, Institute of Life Sciences, Federal University of Juiz de Fora, Campus Governador Valadares
(UFJF-GV), Governador Valadares, MG 35032620, Brazil.
(6)Postgraduate at Biochemistry and Immunology, Federal University of Minas Gerais, Belo Horizonte, MG, 31270901, Brazil; Postgraduate at Biochemistry and Pharmacology, Federal University of Espírito Santo, Vitória, ES, 29047105, Brazil; Postgraduate at Biotechnology, Federal University of Espírito Santo, Vitória, ES 29047105, Brazil. Electronic address: [Email]

Abstract

The study of the biological activity of trypsin isoforms in aqueous-organic media is of great interest to various fields of knowledge and biochemistry applications. Thus enzymatic, structural, and energetic properties of bovine β- and α-trypsin isoforms were compared in aqueous-organic media using 30 mg of each isoform. The results showed that the changes induced on the structure and activity of the same trypsin isoform occur at different concentrations. Better results for activity (ionic strength of 0.11 mol·L-1, at 37 °C and pH 8.0) were found in 0-40% of ethanolic media in which the activity for β-trypsin was about 60% higher than ɑ-trypsin. The ethanolic system does not cause significant changes in the level of secondary structure but the β-trypsin isoform undergoes a major rearrangement. The use of until 60% (v/v) ethanol showed that β-trypsin presents a denaturation process 17% more cooperative. The organic solvent causes redistribution in the supramolecular arrangement of both isoforms: all concentrations used induced the β-trypsin molecules to rearrange into agglomerates. The ɑ-trypsin rearranges into agglomerates up to 60% (v/v) of ethanol and aggregates at 80% (v/v) of ethanol. Both isoforms keep the enzymatic activity up to 60% (v/v) of ethanol.