Comparative studies on thermodynamic characteristics of pea legumin and legumin-T thermal denaturation.
Characteristics of thermal denaturation of pea legumin and a product of its limited proteolysis with trypsin - legumin-T, in a wide range of NaCl concentrations have bean measured by means of differential scanning microcalorimetry. By the increase of NaCl concentration, the number of cooperative units (domains) increases from 1 per one polypeptide chain to 2 for legumin and 1.8 for legumin-T. Deconvolution of denaturation peaks have revealed up to three peaks, which were ascribed to the dissociation of protein macromolecules to subunits and the unfolding of alpha- and beta-polypeptide chains. The analysis of experimental data based on some assumptions showed that the splitting of C-termini of alpha-chains, which are not constituents of cooperative domains, in the course of limited trypsinolysis results in destabilization of the quaternary structure of legumin and loosening of alpha-chains, as well as decrease of the temperatures of their maximum stability.
Kozhevnikov
G O
GO
Russian Academy of Sciences, N.M. Emanuel Institute of Biochemical Physics, 4 Kosygin St., 119991, Moscow, Russia.
Danilenko
A N
AN
Braudo
E E
EE
Schwenke
K D
KD
D002151:Calorimetry; D002152:Calorimetry, Differential Scanning; D006358:Hot Temperature; D018532:Pisum sativum; D010940:Plant Proteins / Q000737:chemistry*; D011485:Protein Binding; D011489:Protein Denaturation; D017510:Protein Folding; D017434:Protein Structure, Tertiary; D012965:Sodium Chloride / Q000494:pharmacology; D013696:Temperature; D013816:Thermodynamics; D000097793:Legumins
D010940:Plant Proteins; D012965:Sodium Chloride; D000097793:Legumins