disulphide bridge

disulphide bridge

the covalent bond between two sulphur atoms, particularly in peptides and proteins.
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Based on our generated Ctd1 model, three disulphide bridges (Cys14-Cys35, Cys20-Cys41 and Cys24-Cys43) sustain the specific CS[alpha][beta] architecture and the fourth disulphide bridge (Cys3-Cys47) links the amino and carboxyl terminal to form a particularly stable protein [21].
Defensins are small in size (5-6 kDa), basic, cysteine rich peptides containing 45-54 amino acids, stabilized by eight cysteine residues that form four conserved disulphide bridges [4,41,34].
Later, once the UT receptor was identified as a member of somatostatin receptor family, some somatostatinlike peptides containing a disulphide bridge, such as human melanin-concentrating hormone (MCH), somatostatin-14, cortistatin-14, and octreotide, were screened on UT receptor in order to compare the resulting biological activities with that of the endogenous U-II [9].
considered the replacement of the disulphide bridge by a side-chain-to-side-chain lactam bridge in accordance with observations on several biologically relevant peptides, such as conotoxins, endothelin-1, and somatostatin analogue that gave interesting results by the same modification [29].
The main active components are mistletoe lectins, ribosome-inactivating proteins of type II consisting of two protein chains linked by an intermolecular disulphide bridge. Clinical studies have shown that mistletoe lectin I enhances the secretion of cytokines and interleukins and increases the number of natural killer cells.
In particular, folding of the protein that involves disulphide bridges hinders glycosylation, as seen in interleukin 6, where the elimination of the disulphide bridge between Cys 45 and Cys 51 increases the efficiency of glycosylation at Asn 46 (16).
The expression and stability of single recombinant domains ending in a Cys residue involved in disulphide bridge formation can be obtained by the addition of residues at either end of the domain (31,36).
Thiol consists of a sulfhydryl group, and under conditions of OS these functional groups form reversible disulphide bridges (9).
The strongest of these cross-links are covalent disulphide bridges. The barrier properties of WPI-based films can be improved by increasing the number of strong intermolecular interactions such as covalent cross-links [6,7].
Based on these data, we can conclude that the basal glutathionylation is a cotranslational modification which, for example, is necessary to prevent the formation of disulphide bridges between the neighboring cysteine residues during protein folding.
The conformation of 17 disulphide bridges of serum albumin molecule can be sensitively determined by Raman spectroscopy.
Table 1: ICH Topic Q6 B (Specifications: test procedures and acceptance criteria for biotechnological/biological products) Appendix for Physiochemical Characterization Structural characterization and confirmation a) Amino acid sequence b) Amino acid composition c) Terminal amino acid sequence d) Peptide map e) Sulfhydryl groups and disulphide bridges f) Carbohydrate structure Physicochemical properties --Molecular weight or size --Isoform pattern --Extinction coefficient --Electrophoretic patterns --Liquid chromatographic patterns --Spectroscopic profiles