The quenching of the tryptophan fluorescence of avidin by biotin forms the basis for a rapid, sensitive assay for biotin and avidin in solutions free of fluorescent contaminants. Avidin solutions are assayed by titration with a standard biotin solution until no further decrease in fluorescence at 35
A Biotin Capture Assay for Oligosaccharyltransferase
β Scribed by Anjali Srinivasan; James K. Coward
- Publisher
- Elsevier Science
- Year
- 2002
- Tongue
- English
- Weight
- 95 KB
- Volume
- 306
- Category
- Article
- ISSN
- 0003-2697
No coin nor oath required. For personal study only.
β¦ Synopsis
Oligosaccharyltransferase (OST) catalyzes the en bloc transfer of dolichylpyrophosphate oligosaccharides to an asparagine residue found in the sequon Asn-Xaa-Thr/Ser of newly synthesized proteins. Currently the method most commonly used to monitor this reaction, involving multiple solvent extractions and HPLC, is extremely time consuming and tedious. Herein, we present the use of a biotinylated peptide as the acceptor substrate and dolichylpyrophosphate [3H]chitobiose as the donor substrate for the OST-catalyzed reaction. This allows for separation (avidin-agarose beads) and quantitative analysis (scintillation counting) of only the biotinylated glycopeptide product of the OST-catalyzed reaction. This new assay yields highly reproducible results in a rapid manner.
π SIMILAR VOLUMES
A competitive binding assay for biotin, biocytin, and desthiobiotin utilizing a genetically engineered enzyme-ligand conjugate is described herein. This assay is unique in that the enzyme-ligand conjugate consists of the streptavidin binding peptide Strep-tag II, which mimics the binding of biotin t
to labeled biotin results in an inhibition of the signal Biotinylated recombinant aequorin was used in the generated by the label (3-8). The higher the amount development of a heterogeneous bioluminescence of free biotin present, the less labeled biotin is bound binding assay for biotin. This assay