Bradford protein assay

About: Bradford protein assay is a research topic. Over the lifetime, 635 publications have been published within this topic receiving 239107 citations.

Continuous aqueous phase extraction of proteins: automated on-line monitoring of fumarase activity and protein concentration

Abstract: Automated assay techniques are described for on-line measurements of fumarase activity and total protein concentration, including in-line sample dilution and sample multiplexing during continuous aqueous phase extraction. Fumarase was determined by following the conversion of L-malate to fumurate at a wavelength of 250 nm, while the protein assay was based on the Biuret reaction. Actual assay times of 2 and 4 min were achieved for the fumarase and protein measurements, respectively, with an effective measurement cycle time of 2 min. Standard deviations of c. 3.2 and 2% of the measured values were calculated for the enzyme and protein values, respectively. The assay system was coupled to a computer to allow on-line data visualization and storage.

Determining protein patterns for three fungus species Aspergillus fumigatus, Asp. flavus and Asp. niger, obtained from outdoor air in Iran.

Abstract: Aspergillus species are saprophytic fungi widely distributed in nature and are associated with a number of human disease. The aim of this study was to compare electrophoretic protein patterns Aspergillus fumigatus, Asp. flavus and Asp.niger and identify the differences of three protein patterns. In this study, three species of Aspergillus fumigatus, Asp.flavus and Asp.niger which were separated from outdoor air in Iran were used to compare electrophoretic protein patterns antigens isolated of Aspergillus. First, these fungi were grown in saboraud glucose agar and preserved at 27°C for 48-72 hours and then they were cultured in saboraud glucose broth to provide protein extract of above mentioned fungi and Bradford method was used in order to measure the level of fungi extracts protein. Protein was dissociated by means of sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) with 11% separating gel. The gel was stained with coomassie brilliant blue G250 and after stabilizing, gel staining and disstaining, different protein bands were appeared. Results revealed, 69 protein bands with molecular weights between 11/5 and 178KD. Among these bands, protein bands with molecular weights of 15, 23/5, 27, 33/5 and 61KD are in two species of Asp.fumigatus and Asp.flavus, protein bands 28/5, 40 and 47KD are in two species of Asp.flavus and Asp.niger, the band with 120 KD is in Asp.fumigatus and Asp.niger and protein bands 23, 35 and 36 KD are among these bands which were presented in every three species of Aspergillus. In addition, a number of strong and weak protein bands were recognized. It was concluded that there was no meaningful relation between protein bands, which were obtained from isolated fungal sp. under study and these three isolates did not follow the same electrophoretic protein patterns.

Composition and method of assaying for trace amounts of proteins

Abstract: A new and improved method and composi­tion for determining the presence and concentra­tion of low to trace amounts of proteins, such as albumin, in a test sample, such as urine. The method includes using a reagent composition capable of interacting with low to trace amounts of proteins to produce a visually or instrument­ally detectable and/or measurable response. The method can be used in wet assays or in dry test strip assays, wherein the reagent composition is incorporating into a carrier matrix. The new and improved reagent composition, comprising a dye, such as a polyhydroxybenzenesulfonephthalein-­type indicator, like pyrocatechol violet; a tung­state, such as ammonium tungstate; and, if neces­sary, a suitable buffer, is incorporated into the carrier matrix to provide sufficient sensi­tivity to low to trace protein levels and suffi­cient color resolution between low to trace pro­tein levels, thereby affording an accurate and trustworthy protein assay of test samples having a low protein concentration.

Microbial Physiology and Biochemistry Laboratory: A Quantitative Approach

Abstract: Introduction Acknowledgements Laboratory Rules and Safety Experiment 1: An exercise in pipetting and the Beer-Lambert Law Experiment 2: Bacterial growth curve Experiment 3: Bioassay for micotinic acid Experiment 4: The effect of environment on growth Experiment 5: Lactic acid production by lactic acid bacteria Experiment 6: Assay of protein and RNA in whole cells grown at different growth rates Experiment 7: Analysis of diauxic growth Experiment 8: Assay of amylase and protease secreted by Bacillus Subtilis Experiment 9: Concentration of amylase from Bacillus Subtilis by ammonium sulfate precipitation and separation from protease by affinity purification Experiment 10: Ion-exchange chromatography of amylase Experiment 11: Induction of alkaline phosphatase and the determination of its cellular cation in Escherichia coli Experiment 12: Assay of threonine deaminase: Determination of KM and Vmax Experiment 13: Assaying fructose-1,6-bisphosphatase in Saccharomyces cerevisiae Experiment 14: Purification of glucose-6-phosphate dehydrogenase Experiment 15: How E. coli adapts to anaerobiosis: Nitrate reductase Experiment 17: Chemotaxis of Pseudomonas aeruginosa Experiment 18: Phototasix of Rhodospirllum centenum Experiment 19: Light production by Phorobacterium phosphoreum Appendix A: Analysis of experimental data: How to do simple dilutions Guidelines for writing laboratory reports Appendix B: Laboratory supplies and equipment Appendix C: Media Buffers Solutions Appendix D: RNA assay using orcinol Lowry protein assay Bradford Protein assay Assay for *a-amylase using starch conjugated to a dye Appendix E: The Beer-Lambert law Relative absorbancies Cell density vs. Klett units Appendix F: Quantitative problems Appendix G: Solutions to problems in Appendix F Appendix H: Determining the amount of inorganic phosphate that limits the growth yields of E. coli, Factors that affect the relative amounts of saturated unsaturated, and branched chain fatty acids Measuring the KM and Vmax of fructose-1,6-bisphosphatase and the inhibition by AMP Assaying glycolytic enzymes and fructose-1,6-bisphosphatase in yeast grown on glucose or ethanol Regulation of phosphofructokinase activity Further experiments and demonstrations with Photobacterium