Sodium dodecyl sulfate extract

Figure 13 Map of protein distribution in single wheat starch granules before (left) and after (right) sodium dodecyl sulfate extraction. Granules were scanned after staining with acid fuchsin (from [46]).

Fig. 15. Polysomal mRNP from reticulocytes. A. Sucrose gradient sedimentation of the polyribosomal suspension after EDTA treatment (40 hours centrifugation). B.Sucrose gradient sedimentation of unlabeled, sodium dodecyl sulfate-extracted polyribosomal RNA supplemented with the high specific radioactivity RNA detached from labeled polyribosomes by EDTA treatment. C. CsCi equilibrium sedimentation of the messenger ribonucleoprotein complex. Ribosomal subparticles have been added as Internal markers. The centrifugation was carried out at 4°C for 18 hours at 36,000 rpm in an SW-39 rotor. (From Huez et al. 1967. Biochim. Biophys. Acta, 145 629-636 Burny et al. 1969. Biochim, Biophys. Acta, 190 228-231.)...

Sample preparation Homogenize (Duall ground glass grinder) 1 g of tissue with q 50 mM pH 8.5 Tris HCl buffer containing 3% sodium dodecyl sulfate, extract th° times with 2 vol of ethyl acetate n-propanol 90 10. Evaporate the combined extra t dryness at 45°, reconstitute the residue with MeOH, inject an ahquot. c s to... 

Fig. 3. Sodium dodecyl sulfate—polyacrylamide gel electrophoretic pattern for molecular weight standards (lane 1) water-extractable proteins of defatted soybean meal (lane 2) purified IIS (glycinin) (lane 3) and purified 7S (P-conglycinin) (lane 4) where the numbers represent mol wt x 10. The gel was mn in the presence of 2-mercaptoethanol, resulting in the cleavage of the disulfide bond linking the acidic (A bands) and basic (B bands) polypeptides of the...

Similarly to quantitative determination of high surfactant concentrations, many alternative methods have been proposed for the quantitative determination of low surfactant concentrations. Tsuji et al. [270] developed a potentio-metric method for the microdetermination of anionic surfactants that was applied to the analysis of 5-100 ppm of sodium dodecyl sulfate and 1-10 ppm of sodium dodecyl ether (2.9 EO) sulfate. This method is based on the inhibitory effect of anionic surfactants on the enzyme system cholinesterase-butyryl-thiocholine iodide. A constant current is applied across two platinum plate electrodes immersed in a solution containing butyrylthiocholine and surfactant. Since cholinesterase produces enzymatic hydrolysis of the substrate, the decrease in the initial velocity of the hydrolysis caused by the surfactant corresponds to its concentration. Amounts up to 60 pg of alcohol sulfate can be spectrometrically determined with acridine orange by extraction of the ion pair with a mixture 3 1 (v/v) of benzene/methyl isobutyl ketone [271]. 

A highly sensitive method for the determination of anionic surfactants, particularly sodium dodecyl sulfate, has been described [275]. The method is based on the formation of fluorescent ionic complexes of the anionic surfactant with acridine red and acridine yellow. The complexes are extracted with dichloro-... 

The ion pair extraction by flow injection analysis (FIA) has been used to analyze sodium dodecyl sulfate and sodium dodecyl ether (3 EO) sulfate among other anionic surfactants. The solvating agent was methanol and the phase-separating system was designed with a PTFE porous membrane permeable to chloroform but impermeable to the aqueous solution. The method is applicable to concentrations up to 1.25 mM with a detection limit of 15 pM [304]. 

Regression correlation coefficient Regression coefficient of determination Rolling circle amplification Water solubility Sodium dodecyl sulfate Supercritical fluid extraction Standard operating procedure Solid-phase extraction Surface plasmon resonance Thymine... 

Homogenize 50 g of a prepared sample with a solution containing 50 mL of borate buffer (pH 10) and 50 mL of acetone in a blender for 5 min. Pour the homogenate into an Erlenmeyer flask, add 50 mL of acetone and shake the flask for 10 min using a shaker. Filter the aqueous acetone extract through a 25G-4 glass filter overlaid with 3 g of Celite. Wash the residue on the filter with 50 mL of acetone. Combine the filtrates and remove acetone by rotary evaporation. Transfer the residue with 5 mL of 4% sodium dodecyl sulfate aqueous solution into a separatory funnel, extract the solution with two portions of 50 mL of dichloromethane and collect the organic... 

Other workers used 0.1 m acetic acid for gluten separation then changed to dilute hydrochloric acid followed by neutralisation with sodium hydroxide.8 Byers et al. used 50% propan-l-ol in preference to 70% ethanol.9 Methods based on extraction with sodium dodecyl sulfate (SDS) have been developed by Danno10 as well as Graveland et al.11,12 Sonication of the SDS extract was introduced by Singh et al.13,14 Burnouf et al. introduced the use of dimethyl sulfoxide (DMSO) to remove monomeric proteins and a few small gliadins.15... 

Fusion protein pull-down assays involve the overexpression of bait and/or fusion proteins in bacteria. Often, the expressed fusion proteins are localized in occlusion bodies and not readily soluble under nondenaturing conditions. The expressed proteins can be extracted using urea, sonication, sodium dodecyl sulfate (SDS), or a combination of all the three. The net result is the denaturation of the recombinant protein and it may need to be refolded if the interaction domain is conformationally dependent. A major advantage of the pull-down assay is that high concentrations of proteins can be easily generated thus favoring protein association for a reversible equilibrium between two proteins. 

Figure 6.5. Immunoblot of the urease large subunit. Extracts of H. pylori wild type (WT) and a hypA mutant from cells grown without nickel supplementation were subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and identified by blotting with an anti-urease large-subunit antiserum. Urease activity was 58pmolmin mg for the wild type and Opmolmin" mg for the hypA mutant.

Clostridium sticklandii also expresses a proline reductase that can reduc-tively cleave proline to 8-aminovalerate (Seto and Stadtman 1976). PR was first purified by Seto and Stadtman (1976) by following the decomposition of proUne in the presence of dithiothreitol or NADH. They found PR to have a denatured mass of approximately 30kDa (sodium dodecyl sulfate-polyacrylomide gel electrophoresis SDS-PAGE) and a native size of approximately 300 kDa. The addition of selenite to the growth medium of C sticklandii did increase the specific activity of PR in extracts by threefold however, no selenium was detected in the purified enzyme. It should be noted that this purified enzyme had lost the ability to couple reduction of proline to NADH and thus probably was missing one or more components of the complete enzyme complex. 

Most of the applications of HPLC for protein analysis deal with the storage proteins in cereals (wheat, corn, rice, oat, barley) and beans (pea, soybeans). HPLC has proved useful for cultivar identihcation, protein separation, and characterization to detect adulterations (illegal addition of common wheat flour to durum wheat flour) [107]. Recently Losso et al. [146] have reported a rapid method for rice prolamin separation by perfusion chromatography on a RP POROS RH/2 column (UV detection at 230nm), sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis (PAGE), and molecular size determination by MALDl-MS. DuPont et al. [147] used a combination of RP-HPLC and SDS-PAGE to determine the composition of wheat flour proteins previously fractionated by sequential extraction. 

A study of the foaming capacities and stabilities [10] of a variety of air-entraining agents in a solution of cement extracts showed that commonly used anionic air-entraining agents, such as sodium dodecyl sulfate and sodium resinate (1) were visually precipitated from solution, (2) retained their ability to form stable foams after precipitation with only minor amounts of admixture left in solution, and (3) lost the major part of their ability to form stable foams after filtration. It was further shown from studies in cement pastes firstly that the admixture should be adsorbed on the solid particles of the paste with the non-polar ends of the molecule pointed towards the water phase, imparting a hydrophobic character to the cement... 

Anionic surfactant Sodium dodecyl sulfate (SDS, C] 2 25 3 supplied by Nihon Surfactant Industries Co., Ltd Tokyo, Japan. It was extracted with ether and recrystallized from ethanol. The purity was ascertained by surface tension measurement. Nonionic surfactant Alkyl poly(oxyethylene) ether (CjjPOEjj, CmH2nhPlO(CH2CH20)2oH, m=12, 14, 16, and 18 Ci6H330(CH2CH20) H, n=10, 20, 30, and 40) were supplied by Nihon Surfactant Industries Co., Ltd. These have a narrow molecular weight distribution. 

Octadecyldimethylamine oxide (CieDAO) was a commercial sample from Onyx Chemical Company, Jersey City, N. J. (25% active). After evaporating the solvent in a rotary evaporator under reduced pressure, the crude product was recrystallised several times from ethyl acetate. The final product was dried and stored in vacuo over P2O5. Sodium octadecyl sulfate (SODS) was a sample prepared in this laboratory previously, and was recrystallised from ethanol before use. Sodium dodecyl sulfate (SDS) was obtained from Aldrich Chemical Company, and was of 98% purity. It was further purified by repeated crystallisation from ethanol followed by ether extraction. Benzene and methanol were gold-label reagent grade, purchased from Aldrich Chemical Company (Metuchen, N. J.). 

Evidence for variation in molecular size of gluten proteins was obtained when protein extracts of flour were chromatographed on agarose gel filtration columns (Sephadex C1-4B) in tris buffer containing sodium dodecyl sulfate as shown in Figure 7... 

For some studies, washed lipid globules can be used as such. More commonly, it is necessary to dissociate membranes from globules by chemical or physical methods. Chemical methods normally involve direct extraction of constituents from the globules. Sodium dodecyl sulfate solutions have been used to recover membrane proteins from washed lipid globules for subsequent electrophoretic characterization (Kobylka and Carraway 1972 Mather and Keenan 1975). Other workers have used solutions of detergents such as deoxycholate (Hayashi and Smith 1965) and Triton X-100 (Patton 1982). With these deter-... 

Figure 10.7 Polypeptide patterns of material associated with lipid globules of cow s milk. The sodium dodecyl sulfate-polyacrylamide gel in (a) was stained with coomassie blue, and polypeptides in the gel in (b) were visualized with the more sensitive silver stain (Merril ef at. 1981). In both (a) and (b) the left lane contains proteins extracted directly from washed milk...

In Experiment 4, your sample of a-lactalbumin extracted from bovine milk was subjected along with other proteins to sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). After staining with the dye Coomassie Blue, deeply colored bands appeared on the gel wherever there was a protein. You suspected that some of the blue bands on the gel were due to a-lactalbumin. If molecular weight standards were included on the slab gel, you were able to estimate the molecular weight for a-lactalbumin and other proteins. SDS-PAGE is indeed a very effective analytical tool to achieve fractionation of protein mixtures, to analyze purity, and to estimate molecular weight, but it provides no experimental data to prove the identity... 

In general, a crude or partially purified extract is electrophoresed on a sodium dodecyl sulfate polyacrylamide gel (SDS-PAGE) then the protein band is lightly stained and cut out. In the simplest method, the acrylamide gel band is reduced to a pulp, mixed with Freund s adjuvant, and injected. Unfortunately, this technique is not always successful. Its failure can probably be attributed to factors such as the difficulty of disaggregating the acrylamide, the difficulty with which the protein diffuses from the gel, the presence of SDS in large quantities resulting in extensive tissue and cell damage, and finally, the toxicity of the acrylamide... 

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