Bovine serum albumin Subject

Besides the previously mentioned collagen, a wide variety of natural polymers have been involved in the synthesis of bio-nanohybrid materials with potential application in bone repair and dental prostheses. For instance, some recent examples refer to bionanocomposites based on the combination of HAP with alginate [96,97], chitosan [98,99], bovine serum albumin (BSA) [100], sodium caseinate [101], hyaluronic acid [102], silk fibroin [103,104], silk sericin [105], or polylactic add (PLA) [106,107]. These examples illustrate the increasing interest in the subject of HAP-based biohybrid materials, which has led to almost 400 articles appeared in scientific journals in 2006 alone. 

The finding that the administration of 6-mercaptopurine to rabbits following exposure to bovine serum albumin prevented antibody formation [374] formed the basis for a new area of chemotherapy for purine analogues and other antimetabolites and was soon followed by the use of these drugs for the therapy of autoimmune disease and the suppression of homograft rejection. This subject has been reviewed in depth [ 12, 375, 375a], has occasioned a symposium [376], and has received much recent publicity as a result of human heart transplants. 

Chemical reactions Polymerization of casein and whey proteins are due to some kind of chemical reactions. The different proteins as found in the supernatant of milk after precipitation at pH 4.6 are collectively called whey proteins. These globular proteins are more water soluble than caseins and are subject to heat dena-turation. Denaturation increases their water-binding capacity. The principal fractions are P-lactoglobulin, a-lactalbumin, bovine serum albumin (BSA), and immunoglobulins (Ig). 

In this experiment, you will evaluate the binding of the dye phenol red to bovine serum albumin. Increasing amounts of dye will be added to fixed amounts of protein in buffered solutions. The reaction mixture will be subjected to gel filtration to separate the dye-protein complex from free, unbound dye. Two types of binding studies can be completed ... 

All the treated and untreated transgenic tobacco plant samples were ground and sieved to 40 mesh prior to the Elcd activity assay. Elcd was extracted from the treated and untreated samples as described by Ziegel-hoffer et al. (15). The total protein of each of the extracts was measured by the Bradford (16) method using bovine serum albumin as a standard. Subsequently the appropriate amount of extract containing the same amount of total protein was subjected to the activity assay. 

With the exception of studies on bovine serum albumin (BSA) and human transferrin, all other digests were carried out on Coomassie Blue-stained gel bands that had been excised from SDS polyacrylamide gels and submitted in eppendorf tubes to the internal protein sequencing service of the HHMI Biopolymer Laboratory/W.M. Keck Foundation Biotechnology Resource Laboratory at Yale University (5). The BSA and transferrin samples were subjected to SDS-PAGE in the Keck Facility and were otherwise prepared as described (5). Proteins were quantified by subjecting 10-15% aliquots of all gel slices to hydrolysis and ion exchange amino acid analysis (5). 

Figure 5. Reverse phase HPLC of in gel tryptic digests of 25 pmol transferrin (A) and 10 pmol bovine serum albumin (B) and of the corresponding digests carried out on blank sections of gels (lower profiles shown in above two figures). In each instance 90% of the digest was subjected to HPLC on a 1.0 mm ID Vydac C-18 coluttm eluted at 50 pl/min. The respective full scale deflections were 18.9 mV for panel A and 4.4 mV for panel B with 0.5 volt corresponding to an absorbance of 1.0 at 210 nm.

Time-dependent offline sampling of 1 ml aliquots was performed aseptically during fermentations. Samples were mixed immediately before dilution in deionized water, and then subjected to duplicate absorbance determination in a spectrophotometer at 600 nm. Diluted cell-free medium was used to establish background readings and set zero absorbance levels. Values were averaged and corrected for dilution. Protein concentration in cell-free extracts was determined by Bradford method [21], using bovine serum albumin as a standard. 

Basic proteins protamine (pKj = 12.4) and histone (pKj = 10.8) did not inhibit attachment. The effect of proteins on attachment were independent of surface charge density on the substratum and thus the decreased attachment in the presence of proteins may be due to non-electrostatic interactions. The behaviour of bovine serum albumin, which has a large number of non-polar side chains, indicates that hydrophobic interactions may be important (Tanford, 84 Goldsack and Chalifux, 85). The effects of hydrophyllic colloids on bacterial floccuTation have been studied by Hodge and Metcalfe (86) and the subject has been reviewed by Harris and Mitchell (87). 

In order to purify the RBCs, the plasma and huffy coat (white cells) are removed for further purification (see above). RBCs are then resuspended and washed three times in a physiological salt solution [PSS in mM, 4.7 KCl, 2.0 CaCh, 140.5 NaCl, 12 MgS04,21.0 tris(hydroxymethyl)aminomethane, 11.1 dextrose with 5% bovine serum albumin (final pH 7.4)]. Cells should generally be prepared and studied on the day of use within 8 h of removal from animal or human subjects. 

In a subject with rhinitis, conjunctivitis and asthma due to phthalic anhydride and giving immediate skin and bronchial reactions to appropriate solutions, Maccia et al. (1976) have obtained a positive RAST for specific IgE antibodies to a conjugate of phthalic anhydride and bovine serum albumin. Passive transfer of skin test sensitivity to phthalic anhydride has been reported (Kern 1939), and lymphocyte transformation has also been reported (Gervais et al. 1972). 

Figure 19. A Gel filtration pattern of a 40X1 tryptic hydrolysate (1 hr) of bovine serum albumin. The hydrolysate (0.3 g) was applied onto a column (2.7 x 80 cm) of Sephadex G-100 which was eluted with 0.01 M NH HCOs. Fractions (7.5 ml each) were analyzed continuously by an ultraviolet monkor. B Chromatogi hic pattern on DEAE-cellulose of peak 3 from A. The material (100 mg) was applied on a column (1.5 x 20 cm) which was subjected to stepwise elution. Initial elution was with 0.005 M sodium phosphate buffer at pH 6.2. At positioa 2 the column was eluted with 0.0175 M phosphate buffer pH 6.2, and at portion 3 the ehient was changed to 0.0175 M phosphate pH 6.2 plus 0.077 M NaCl. Fractions (3 ml) were read continuously by an ultraviolet monitor. From Habeeb and Atassi (19766).

In addition, the membranes were subjected to the separation of proteins such as bovine serum albumin, egg albumin, pepsin, and trypsin [84]. 

Preparation of Cells. Assays for DNA damage (and Ho33342 uptake) were carried out on cultures which had been subjected to a standard protocol for the generation of freeze/thawed (permeabilised) cells directly from monolayer, adapted [17, 18] from the method described by Ganesan et al. [19]. Cells were resuspended in a low salt (LS) buffer (10 mM Tris-HCl, pH 8 100 mM NaCl 10 mM EDTA 1 mg ml bovine serum albumin). 

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