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.

Interactions of long-chain fatty acids and albumin: determination of free fatty acid levels using the fluorescent probe ADIFAB.

Abstract: Equilibrium binding of long-chain fatty acids (FA) with albumin from human serum (HSA), bovine serum (BSA), and murine serum (MSA) has been studied by measuring the equilibrium levels of free fatty acids (FFA) FFA levels were measured directly, using a new fluorescent probe composed of acrylodan-derivatized intestinal fatty acid binding protein (ADIFAB) Measurements of [FFA] were done as a function of the ratio of total FA to total albumin (v) for v values between 0 and 6, at pH 74 and 37 degrees C Under conditions observed in normal human physiology (v < or = 2), [FFA] values of the most abundant serum FA (palmitate, stearate, oleate) in equilibrium with human or bovine albumin are less than 15 nM These values are considerably smaller than the generally quoted values of [FFA] in equilibrium with albumin: more than 20-fold for palmitate and more than 50-fold for oleate FFA levels were found to increase monotonically with for all three albumins and all FA In most cases [FFA] increased, for the same chain length, with increasing degree of acyl chain unsaturation, suggesting that FA aqueous solubility may play a significant role in the equilibrium between FA association with albumin and the aqueous phase [The highest FFA levels (approximately 3000 nM), for example, were observed for linoleate (18:3) at the maximum v value (6)] Although aqueous-phase solubility of the FA may be important in understanding the interaction between FA and albumin, protein structure, as reflected in differences among the three albumins, also significantly affects the equilibrium(ABSTRACT TRUNCATED AT 250 WORDS)

Protein Digestion in Human Intestine as Reflected in Luminal, Mucosal, and Plasma Amino Acid Concentrations after Meals

Abstract: Normal human volunteers were intubated with either aspiration tubes or a biopsy capsule placed in the small intestine. The subjects were then fed a test meal containing 50 g of purified bovine serum albumin which served as the model dietary protein. Electrophoretic analysis of intestinal fluids showed that for at least 4 h the fed albumin was detectable in jejunal and ileal fluids. On separate occasions, subjects were fed the same meal without the protein. No protein was detected in intestinal fluids when the protein-free meal was fed. After the protein-rich meal, total concentrations of measured free and peptide amino acids rose from 3.21 to 29.29, and 15.94 to 117.97 mumol/ml, respectively, (P values < 0.02) in the jejunum. Similarly, total concentrations of measured free and peptide amino acids rose from 5.45 to 19.74, and 13.59 to 65.39, respectively, (P values < 0.05) in the ileum. In contrast, concentrations of free and peptide amino acids in intestinal fluids did not increase after the protein-free meal. While intracellular concentrations of amino acids in the jejunal mucosa did not show significant changes, plasma concentrations of each individual free amino acid were increased after the protein-rich meal and were either decreased or unaltered after the protein-free meal. The amino acid composition of the fed protein was reflected in the increases in intraluminal and plasma concentrations of individual amino acids after the protein-rich meal. It is concluded that after the ingestion of a test meal containing a substantial amount of protein which is within the usual range of dietary intake; (a) the exogenous protein is the principal source of the increased free and peptide amino acids in the intraluminal contents and in the plasma; (b) there are greater amounts of amino acids present as small peptides than in the free form in the gut lumen; (c) the ingested protein can be recovered as late as 4 h both in the jejunum and in the ileum.

A virus discovery method incorporating DNase treatment and its application to the identification of two bovine parvovirus species.

Abstract: Identification of previously unrecognized viral agents in serum or plasma samples is of great medical interest but remains a major challenge, primarily because of abundant host DNA. The current methods, library screening or representational difference analysis (RDA), are very laborious and require selected sample sets. We have developed a simple and reproducible method for discovering viruses in single serum samples that is based on DNase treatment of the serum followed by restriction enzyme digestion and sequence-independent single primer amplification (SISPA) of the fragments, and have evaluated its performance on known viruses. Both DNA viruses and RNA viruses at a concentration of ≈10 6 genome equivalents per ml were reproducibly identified in 50 μl of serum. While evaluating the method, two previously unknown parvoviruses were discovered in the bovine sera used as diluent. The near complete genome sequence of each virus was determined; their classification as two species (provisionally named bovine parvoviruses 2 and 3) was confirmed by phylogenetic analysis. Both viruses were found to be frequent contaminants of commercial bovine serum. DNase treatment of serum samples may prove to be a very useful tool for virus discovery. The DNase-SISPA method is suitable for screening of a large number of samples and also enables rapid sequence determination of high-titer viruses.