In the major pathway for protein disulfide-bond formation in the endoplasmic reticulum (ER), oxidizing equivalents flow from the conserved ER-membrane protein Ero1p to secretory proteins via protein disulfide isomerase (PDI). Herein, a mutational analysis of the yeast ERO1 gene identifies two pairs of conserved cysteines likely to form redox-active disulfide bonds in Ero1p. Cys100, Cys105, Cys3...

Chloroplast fructose 1,6-bisphosphatase (FBPase) is activated by reduction of a regulatory disulfide through thioredoxin f (Trx f). In the course of this reduction a transient mixed disulfide is formed linking covalently Trx f with FBPase, which possesses three Cys on a loop structure, two of them forming the redox-active disulfide bridge. The goal of this study was to identify the Cys involved...

A method for determining the kinetic fate of structured disulfide species (i.e., whether they are preferentially oxidized or reshuffle back to an unstructured disulfide species) is introduced. The method relies on the sensitivity of unstructured disulfide species to low concentrations of reducing agents. Because a structured des species that preferentially reshuffles generally first rearranges ...

What limited evidence there is indicates that the formulation in which a chemical allergen is encountered on the skin can have a marked impact upon the induction of cutaneous immune responses and the subsequent development of contact sensitization. The purpose of the present investigations was to examine further this phenomenon by analysis of the influence of dibutyl phthalate (DBP) on dermal s...

—The disulfide bonds in γ-46 gliadin were identified: Cys 173 –Cys 192 , Cys 212 –Cys 291 , Cys 165 –Cys 199 (or Cys 200 ), Cys 283 –Cys 200 (or Cys 199 ). The disulfide-containing peptides were obtained by limited hydrolysis of the intact protein with chymotrypsin at an enzyme/substrate ratio of 1:1000 at 20°C for 22 h with subsequent digestion of disulfide-containing fragments with trypsin an...

A novel immobilized N-chlorosuccinimide resin was developed for peptide disulfide bond formation in combinatorial libraries. The resin is prepared in a simple two-step process from commercial starting materials. Disulfide formation is initiated by adding a peptide solution to the resin, and excess reagent is removed by a convenient filtration upon completion of disulfide formation. Completion o...

New measured data for density, (ρ), dynamic and kinematic viscosities, (μD μc), refractive index, (nD), are presented at T = 298.15 K p 0.1 MPa binary ternary mixtures containing dibutyl ether, 2-butanol, cyclohexane. As a result, the derived properties estimated based on data. Excess molar volume, (VE), viscosity deviation (ΔμD), in (ΔnD), as properties, fitted using Redlich–Kister equation. I...

Durand, Kirt Lenroy. Ph.D., Purdue University, December 2014. Determination of Disulfide Bond Connecting Patterns via Tandem Mass Spectrometry (MS) and Biomolecular Ion/Radical Reactions. Major Professor: Yu Xia. Disulfide bond formation is one of the most common post translational modifications to occur in proteins and naturally occurring peptides. Disulfide bond formation plays a critical rol...

A liquid chromatography tandem-mass spectrometry method was developed to map the eleven disulfide bonds in Pfs25, a malaria transmission-blocking vaccine candidate. The compact and complex nature of Pfs25 has led to difficulties in prior peptide mapping efforts. Here, we report confirmation of proper disulfide pairing of a recombinant Pfs25, by optimizing denaturation and digestion with trypsin...