Showing papers in "Analytical Biochemistry in 1977"

TL;DR: A simple method based on a linear log-log protein standard curve is presented to permit rapid and totally objective protein analysis using small programmable calculators.

TL;DR: An assay for proteins in solution that depends on the conversion of Coomassie brilliant blue G250 in dilute acid from a brownish-orange to an intense blue color has high reproducibility and can detect less than 1.0 μg of albumin.

TL;DR: A rapid, simple, and inexpensive procedure is described for the isolation and base analysis of bacterial deoxyribonucleic acids (DNA) in samples of 0.2 mg.

TL;DR: The 230 260 method is less dependent on changes in the amino acid composition of the protein(s) being measured than is the 280 260 method, and results in sensitivity equivalent to that of the method of Lowry, Rosebrough, Farr, and Randall.

TL;DR: All 20 amino acid phenylthiohydantoins (PTHs) can be separated in a single analysis in less than 20 min using a 25 × 0.46-cm DuPont Zorbax ODS column and with this procedure it is possible to keep pace with automated Edman methods.

TL;DR: 4′,6-Diamidino-2-phenylindole · 2HCl (DAPI) forms a specific complex with DNA, and this fact has been used for the quantitative fluorimetric estimation of DNA.

TL;DR: Multiple forms of glutathione S -transferase, a family of proteins involved both with bilirubin transport and with the detoxification of electrophiles, have been purified from human liver using a scheme which employs an affinity chromatography column prepared by coupling glutathion to epoxy-activated Sepharose.

TL;DR: During the cleavage of glycosidic linkages by anhydrous hydrogen fluoride there is little or no degradation of the sugars themselves, thus allowing their quantitative recovery, which may also be useful in the analysis of complex polysaccharides.

TL;DR: Radioactive chitin, prepared by acetylation of chitosan with tritiated acetic anhydride, was used as substrate in a rapid and extremely sensitive assay for chitInase, a result that cannot be attributed to an artifact of the method, to inhibition by product, or to instability of the enzyme.

TL;DR: Improved methods for the activation and assay of d -ribulose-1,5-bisphosphate carboxylase and oxygenase are described and the use of a “CO 2 -free” oxygenase reaction mixture is emphasized along with the difficulties arising from the inevitable carryover of CO 2 into the reaction mixture with the activated enzyme.

TL;DR: The method described measures the total AcH content without regard to any binding in biological samples by head-space gas chromatography, and some of the AcH in rat blood was shown to be bound.

TL;DR: The procedure of SDS-PAGE proposed in this study should provide improved reliability of melecular weight estimates andvalid Rf measurement is a requisite for linear Ferguson plots (log Rf vs %T), since the slope of these plots, KR, is a measure of molecular weight.

TL;DR: This is the first rapid assay proposed for isomerically pure, commercially available juvenile hormone I, and it is proposed that this assay is more rapid and less expensive than conventional chromatographic assays while yielding almost identical values of similar precision.

TL;DR: In the DNA and RNA assays carried out with the use of ethidium bromide in cell and tissue homogenates according to the method of Karsten and Wollenberger, Pronase can be replaced to advantage by heparin in the nucleoprotein dissociation step.

TL;DR: Nucleases can be revealed, following their electrophoretic separation in sodium dodecyl sulfate (SDS)-polyacrylamide gels containing DNA or RNA, by incubating the gels in buffer to remove SDS and to allow renaturation and enzymatic activity.

TL;DR: These substrates are amides of an acyl amino acid or peptide with 7-amino-4-methylcoumarin (AMC) and the detection limits obtained by using the best substrates and short incubation times are: chymotrypsin, 25 ng; tryps in, 5 ng; and elastase, 2 ng.

TL;DR: The most slowly eluting peak, Peak IV, has the highest quantum efficiency and binds irreversibly to acetylcholine receptors on electroplax fragments and labels the fragments more intensely than Peaks I–III, which are identified as mixtures of multiply labeled tetramethyl rhodamine α-bungarotoxin.

TL;DR: Application of the binding of Coomassie brilliant blue G-250 to protein in an acid-denaturing solvent shows that the method is a rapid and reproducible method, but that it is of limited analytical value since it shows a wide variability in its sensitivity to various proteins.

TL;DR: A modification of the method of catalase determination by means of the Clark oxygen electrode is described, based on measurement of the initial rate at which oxygen is released bycatalase in an oxygen-free buffer, which is applicable to an 840-fold range ofCatalase concentrations.

TL;DR: A method based on the conversion of radioactive acetyl-CoA to acetyl(−)carnitine in the presence of carnitine acetyltransferase and oxidized glutathione or N -ethylmaleimide to pull the reaction to near completion achieves linear standard curves over a wide range.

TL;DR: A one-step procedure using a mixed reagent of molybdovanadate and sodium dodecyl sulfate for measuring inorganic phosphate in the presence of proteins is described, which is faster, simpler, and more accurate than the previous colorimetric methods.

TL;DR: A differential centrifugation method is described, which results in final mitochondrial yields of at least 35 to 40 mg of mitochondrial protein per gram wet weight of liver, and these mitochondria are shown to be functionally and ultrastructurally intact.

TL;DR: Addition of sodium bismuth tartrate to a carbohydrate reagent consisting of 4-hydroxybenzoic acid hydrazide in aqueous sodium hydroxide enables the reaction to be carried out more rapidly, at a lower temperature, and with four- to fivefold greater sensitivity.

TL;DR: A rapid, relatively sensitive and highly accurate method of determining 25-hydroxyvitamin D/sub 2/ and 25-Hydroxyv vitamin D/ sub 3/ levels in plasma has been devised.

TL;DR: Two alternative methods of analysis of PAGE results are compared and demonstrated to yield linear relationships for multimeric proteins having molecular weights as high as 900,000.

TL;DR: In this paper, a chromatographic resolution and quantification of the calcium-binding amino acid γ-carboxyglutamate (Gla) is presented, which is extremely acid labile and totally converted to glutamic acid during acid hydrolysis.

TL;DR: A simple procedure for the measurement of submicrogram quantities of protein is described which can be used without interference from most common reagents and can be accurately determined.

TL;DR: During sample preparation, sodium dodecyl sulfate can be included, with a resulting enhancement in reproducibility of gel patterns, but heating in the presence of SDS leads to artifactual spots in the gels, probably as a result of protein charge modifications.

TL;DR: Simple procedures for purifying labeled samples of arsenic III and V, and for interconverting these two forms of arsenic, are described.