Bovine serum albumin

About: Bovine serum albumin is a research topic. Over the lifetime, 19981 publications have been published within this topic receiving 571291 citations. The topic is also known as: BSA.

Identification of low-abundance proteins of bovine colostral and mature milk using two-dimensional electrophoresis followed by microsequencing and mass spectrometry.

Abstract: We identified several low-abundance proteins of bovine colostrum and mature milk using the immunoabsorption technique and two-dimensional electrophoresis (2-DE) followed by microsequencing and mass spectrometry. Two major milk proteins, beta-casein and immunoglobulin G (IgG), were effectively removed from the milk using immunoabsorbents. Milk samples before and after immunoabsorption were separated by 2-DE. Protein identification of the spots on 2-DE was performed by either gel comparison, microsequencing, matrix-assisted laser desorption/ionization-time of flight mass-spectrometry (MALDI-TOF-MS), peptide mass fingerprinting or peptide sequencing using tandem MS by hybrid quadrupole/orthogonal acceleration time of flight-MS (Q-TOF). Significant differences in protein patterns were observed between the low-abundance proteins of colostrum and mature milk. In addition, several low-abundance proteins including fibrinogen beta-chain, chitinase 3-like 1, alpha-antitrypsin, complement C3 alpha-chain, gelsolin and apolipoprotein H were observed only in colostrum. However, the level of beta-casein fragments increased significantly during this lactation period. alpha-Lactalbumin and beta-lactoglobulin as well as some low-abundance proteins including bovine serum albumin, serotransferrin and lactoferrin were identified in both colostral and mature milk. Low-abundance proteins in bovine colostrum may have special physiologic relevance to the health and development of calves early in lactation.

Porphyrin-binding proteins in serum.

Abstract: The presence of porphyrin-binding proteins in mammalian serum is well known. The first of these proteins t o be described was serum albumin.' y 2 $ Both its physicochemical properties and its interaction with heme5 and other porphyrins have been e ~ a m i n e d . ~ However, the interaction of albumin with other ligands such as lipids4 and bilirubin5 has been more thoroughly studied. In 1957, hemopexin, a heme-binding 0-glycoprotein, was discovered6.' and its biochemistry remains a topic of active research.*Although other pophyrinbinding proteins' l ' may exist, little information concerning them is available. The purpose of this review is to summarize the physicochemical properties of serum albumin and hemopexin and present our current concept of their biological function. Emphasis will be placed on aspects germane to their roles in heme and porphyrin metabolism.

Preferential Hydration of Bovine Serum Albumin in Polyhydric Alcohol-Water Mixtures

Abstract: The preferential solvent interaction with bovine serum albumin in aqueous solution of polyhydric alcohols (ethylene glycol, glycerol, xylitol, sorbitol, mannitol, and inositol) was investigated by a densimetric method with the application of multicomponent theory. This proteins was preferentially hydrated in all solvent systems examined: the extent depended on the number and the steric configuration of the hydroxyl groups of alcohols. The absolute interactions of these alcohols with the protein were estimated by assuming that the amount of hydration of protein at every solvent composition used is identical with that in pure water. The preferential hydration of the protein in 30% aqueous solutions of glycerol and sorbitol was found to decrease as the temperature was increased, indicating that the increase in chemical potential of protein on transferring it from water to both aqueous solvents is generated by a large positive enthalpy change, sufficient to compensate for the positive entropy change in the transfer process. On the basis of these results, and mechanism of stabilization of protein structure by these alcohols was discussed from the viewpoint of the solvation of protein.