Serum albumin volume change

They confirm that 0.1 M potassium chloride lowers the pH at which the expansion occurs and yet show that it does not greatly affect the isomerization near pH 4. Since the isomerization is undetectable at 589 m i, the wavelength used by Kauzmann, the optical rotation at this point will not parallel changes as indicated by other techniques. The volume contraction which continues in 0.15 M potassium chloride near pH 4 may therefore reflect a slight unfolding during isomerization, a possibility that is in harmony both with the concomitant exposure of about 20% of the tyrosyl residues in bovine serum albumin as measured by difference spectroscopy and the small loss in helical content. 

The introduction of succinyl residues producing short-range repulsive forces in place of possible short-range attractive forces in the native molecule resulted in a change of hydrodynamic properties of bovine serum albumin (BSA), bovine y-globulin, and /3-lactoglobulin [3], The succinylated derivatives showed markedly increased intrinsic viscosity and Stokes radius and a decrease of sedimentation coefficient [36,37], These results are compatible only with a considerable increase in the effective volume occupied by the succinylated protein molecule compared to its unreacted counterpart. 

The overall protein composition of a patient s plasma or serum should be studied first in terms of its total protein content. The total protein concentration of serum in healthy adults is 60-80 g 1 There are two general causes of alterations of serum total proteins change in the volume of plasma water and change in the concentration of one or more of the specific proteins in the plasma. A decrease in the volume of plasma water (hemoconcentration), as seen in inadequate water intake or excessive water loss, results in relative hyperproteinemia. Hemodilution (increase in plasma water volume), as seen in water intoxication or salt retention syndromes during massive intravenous infusion, is reflected as relative hypo-proteinemia. In these cases the concentrations of all the individual plasma proteins are increased or decreased to the same degree. Individual serum proteins may also cause an increase or decrease of total plasma protein concentration low levels of albumin cause hypoproteinemia (very commonly and with many causes), while a mild hyperproteinemia may be... 

The hyaluronan network retards the diffusion of other molecules. [31], It can be shown that it is the steric hindrance which restricts the movements and not the viscosity of the solution. The larger the molecule the more it will be hindered. In vivo hyaluronan will therefore act as a diffusion barrier and regulate the transport of other substances through the intercellular spaces. Furthermore, the network will exclude a certain volume of solvent for other molecules the larger the molecule the less space will be available to it [32]. A solution of 10 g/L of hyalmonan will exclude about half of the solvent to serum albumin. Hyaluronan and other polysaccharides therefore take part in the partition of plasma proteins between the vascular and extravascular spaces. The excluded volume phenomenon will also affect the solubility of other macromolecules in the interstitium, change chemical equilibria and stabilize the stractme of, for example, collagen fibers. 

In control experiments, the addition of retinal (dissolved in a small volume of ethanol) or bovine serum albumin to the aqueous bath did not produce significant changes in conductance. 

AE, AH. Serum albumin, a protein, combines with 3.0 g Cu " in water to form a charged complex with the absorption of 0.14 kcal. Calculate AE and AH for the reaction serum albumin(aq) + Cu (aq) - serum albumin—Cu +(aq). (Solids and liquids undergo relatively small changes in volume so that tv is negligible.)... 

Bovine serum albumin (BSA) and some other commercially available proteins were the preferred targets for many investigations, above all for the elucidation of the differences between isomolal and isopotential volumes under quite different conditions. Since the extent of possible volume changes... 

An illustrative example of this kind is shown in Fig. 5, where the denaturation of serum albumin was followed upon addition of increasing concentrations of the denaturant GdmCl [83D1], The volume changes observed in densimetric studies were found to parallel changes of the extinction coefficient and intrinsic viscosity. 

Fig. 5a - c. Molecular properties of bovine serum albumin as a function of the molar concentration, C3, of the denaturant guanidinium chloride (from [83D1]). a apparent isopotential specific volume (in cm g ) b extinction coefficient c intrinsic viscosity (in cm g ). For experimental details see the original reference. Reprinted from International Journal of Biological Macromolecules, Vol. 5, H. Durchschlag and R. Jaenicke, Partial specific volume changes of proteins ultracentrifugal and viscometric studies, pp. 143-148, 1983, with permission from Elsevier Science. 

Another antibody was experimentally produced in rabbits by injecting pepsin (G5). It was detected by the Ouchterlony technique and precipitation reactions, and may have some clinical significance in producing atrophy of chief cells. Repeated injection of this immune serum into rats also caused decrease in the volume of gastric juice, with lower concentrations of acid and pepsin. The controls injected with antibodies to egg albumin, nonspecific globulins, and saline did not show similar changes (see Fig. ). 

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