Electrodecantation of serum proteins.

The sedimentation of albumin under the action of the electric and gravitational fields was determined as a function of time in discontinuous experiments in a rectangular cell, using serum with the albumin fraction stained blue. It was shown that even under the influence of strong electric fields, the upper boundary of the albumin layer fell no further than the mid-point of the cell. In continuous single-stage separation of gamma-globulin from other serum proteins, only about half the gamma-globulins can be obtained from the solution because it remains homogeneously distributed throughout the solution and is only free from albumin and other proteins in the upper half of the cell. In experiments with continuously operated triangular cells, the process was optimized to give gamma-globulin of 97.5% purity in a yield of 80%, at serum flow-through rates of up to 0.5 l/h in a block composed of 40 cells.     

Erythrocyte oxidative damage by myeloperoxidase. The protective action of serum proteins

Influence of main serum proteins (albumin, immunoglobulin G) and proteins-antioxidants (ceruloplasmin, transferrin, superoxide dismutase) on the oxidative damage of erythrocytes by myeloperoxidase and hypochlorite was investigated. The proteins were determined to act as protectors and decrease the degree of hemoglobin oxidation, ceruloplasmin and albumin possessing the highest antioxidant activity.     

Interaction of histones with human serum proteins.

The authors describe the interactions of whole calf thymus histone and its fractions with the human serum proteins. Immunoelectrophoretic analysis revealed two types of interactions: 1) a decrease in the electrophoretic mobility of a whole, immunochemically uniform fraction, and 2) a decrease in the electrophoretic mobility of only some molecules of such a fraction. In this association, the arginine-rich histone fraction (F3) was found to be the most active. The findings are important for interpreting the results of biological treatments.     

Degradation of serum proteins in Triatoma infestans.

It has been previously described (Perassi 1972, 1973)that no serum proteins from the animal on which the insects were fed can be detected in the insects' hemolymph of either male or female Triatoma infestans. In other words, the absorption of the proteins does not take place from the gut content to the hemolymph. Furthermore, according to the present investigation, the degradative processes of the gut content has revealed that, at least from an immunological point of view, an almost complete degradation of the rat serum proteins is carried out in the wide and slender midgut of T. infestans. These findings support the conclusion that in T. infestans the absorption of serum proteins from the gut to the hemolymph does not occur unless the proteins have been degradated previously.     

Dye-promoted precipitation of serum proteins. Mechanism and application.

Immobilized dyes have been used primarily for purification of nucleotide dependent enzymes and proteins from plasma and other sources. Due to their low costs, high protein binding capacity and resistance to degradation dyes bear the potential as ligand for affinity separation of proteins on a large scale. In this paper dyes have been used for precipitation of proteins. Using albumin, prealbumin, alpha 1-acid glycoprotein and immunoglobulin G as model proteins we could demonstrate that dye-promoted precipitation depends on several factors which include the structure of the dye, the pH of the solution, the dye/protein molar ratio and the intrinsic properties of the proteins. It revealed that most of the dyes tested were endowed with the precipitating potential. The efficacy of precipitation was found to increase with the complexity of the dye structure. However, the amount of a dye required for total precipitation was found to be different for a given protein. Electrostatic as well as hydrophobic forces are involved in the mechanism of precipitation. It was demonstrated that by optimizing the conditions, mixtures of proteins can be resolved by dye-promoted precipitation. The high sensitivity of the reaction offers the possibility of using this method for rapid concentration of very diluted protein solutions.