Life Sciences Commons^™

A Simple Spectrophotometric Streptavidin-Biotin Binding Assay Utilizing Biotin-4-Fluorescein., Mark Waner, David Mascotti

Mark J. Waner

A new assay for biotin binding capacity of Streptavidin (SA) is presented in this work. The assay is based on the large decrease in the extinction coefficient at 493 nm that accompanies binding of biotin-4-fluorescein (B4F) to SA. This decrease is attributed to formation of a charge transfer complex between the B4F-donor and one or more SA residues. We show that one may observe the stoichiometric binding via monitoring the absorbance at 493 nm using either SA or B4F as the titrant. The sensitivity of the assay is at the lower end of similar fluorimetric and photometric assays. Though the …

A Simple Spectrophotometric Streptavidin-Biotin Binding Assay Utilizing Biotin-4-Fluorescein., Mark Waner, David Mascotti

David P. Mascotti

A new assay for biotin binding capacity of Streptavidin (SA) is presented in this work. The assay is based on the large decrease in the extinction coefficient at 493 nm that accompanies binding of biotin-4-fluorescein (B4F) to SA. This decrease is attributed to formation of a charge transfer complex between the B4F-donor and one or more SA residues. We show that one may observe the stoichiometric binding via monitoring the absorbance at 493 nm using either SA or B4F as the titrant. The sensitivity of the assay is at the lower end of similar fluorimetric and photometric assays. Though the …

Psf2 Plays Important Roles In Normal Eye Development In Xenopus Laevis, Brian Walter, Kimberly Perry, Lisa Fukui, Erica Malloch, Jason Weaver, Jonathan Henry

Brian Walter

No abstract provided.

'Partial Derivatives: Are You Kidding?': Teaching Thermodynamics Using Virtual Substance, Chrystal Bruce, Carribeth Bliem, John Papanikolas

Chrystal D. Bruce

No abstract provided.

Invited Review: Heat Shock Proteins And Exercise: A Primer, Earl Noble, Kevin Milne, C.W. Melling

Jamie Melling

Heat shock proteins (HSPs) are, in general, prosurvival molecules within the cellular environment, and the overexpression of even just 1 family of HSPs can lead to protection against and improvements after a variety of stressors. Not surprisingly, a fertile area of study has grown out of effors to exploit the innate biologic behaviour of HSPs. Exercise, because of the inherent physiologic stresses associated with it, is but 1 stimulus that can result in a robust increase in various HSPs in several tissues, not the least of which happen to be the heart and skeletal muscle. The purpose of this review …

Combating Drug Resistance – Identifying Resilient Molecular Targets And Robust Drugs, Celia Schiffer

Celia A. Schiffer

In: Robert M. Stroud and Janet Finer-Moore, Computational and Structural Approaches to Drug Discovery: Ligand-Protein Interactions, Royal Society of Chemistry, 2008, Chapter 7, p. 127-132. ISBN 0854043659, 9780854043651.

Mechanism Of Cu+-Transporting Atpases: Soluble Cu+ Chaperones Directly Transfer Cu+ To Transmembrane Transport Sites, José Argüello, Manuel Gonzalez-Guerrero

José M. Argüello

As in other P-type ATPases, metal binding to transmembrane metal-binding sites (TM-MBS) in Cu(+)-ATPases is required for enzyme phosphorylation and subsequent transport. However, Cu(+) does not access Cu(+)-ATPases in a free (hydrated) form but is bound to a chaperone protein. Cu(+) transfer from Cu(+) chaperones to regulatory cytoplasmic metal-binding domains (MBDs) present in these ATPases has been described, but there is no evidence of a proposed subsequent Cu(+) movement from the MBDs to the TM-MBS. Alternatively, we postulate the parsimonious Cu(+) transfer by the chaperone directly to TM-MBS. Testing both models, the delivery of Cu(+) by Archaeoglobus fulgidus Cu(+) chaperone …

Structural And Dynamic Basis Of Phospholamban And Sarcolipin Inhibition Of Ca2+-Atpase, Nathaniel J. Traaseth, Kim N. Ha, Raffaello Verardi, Lei Shi, Jarrod J. Buffy, Larry R. Masterson, Gianluigi Veglia

Larry Masterson