Changes of the oligomeric structure of legumin from pea (Pisum sativum L.) after succinylation.

The influence of various levels of succinylation on the structure of the legumin from pea seed has been studied by the techniques of sedimentation velocity, viscometry, fluorescence and circular dichroism spectroscopy, as well as dynamic light scattering. The protein dissociates gradually into the 3S subunit forming a 7S intermediate. At a level of 75-80% succinylation, sudden unfolding of the protein occurs characterized by drastic changes in viscometric and spectroscopic properties.

Isolation of the 12 S globulin from rapeseed (Brassica napus L.) and characterization as a "neutral" protein. On seed proteins. Part 13.

An isolation procedure for the 12 S rapeseed globulin is described which includes precipitation by dialysis, purification using gel chromatography on Sephadex G-200, and ion-exchange chromatography on DEAE-Sephadex A-50. The isolated globulin represents a neutral protein with an isoelectric point at pH 7.25--determined by isoelectric focusing--and a relation of the acidic to basic amino acid residues (epsilon Glu, Asp--Amide ammonia: epsilon Arg, Lys, His) of 1.

[Chemical modification of proteins. 7. Effect of succinylation on some physico-chemical and functional properties of casein].

Succinylation of amino groups of the casein complex results in a spontaneous dissociation of the protein into low-molecular 1.8-S components. Succinylated samples of casein are characterized by a higher electrophoretic mobility of the components in alkaline mediums and by a lower mobility in acidic buffer systems.

Hydrodynamic and quasi-elastic light scattering studies on the 12S globulin from rapeseed.

The 12S globulin, one of the major storage proteins of rapeseeds, has the following physico-chemical constants, as determined by ultracentrifugation, quasi-elastic light scattering measurements and gel chromatography: sedimentation coefficient S20(0), w = 12.7 x 10(-13) s; diffusion coefficient (quasi-elastic light scattering) D20(0), w = 3.8 x 10(-7) cm2 S-1; Stokes radius (by quasi-elastic light scattering) Rs = 5.