The difficulties in predicting disulfide connectivity from protein sequences lie in the nonlocal properties of the disulfide bridges that involve cysteine pairs at large sequence separation. Though some progress has been recently made in the prediction of disulfide connectivity, the current methods predict less than half of the disulfide patterns for the data set sharing less than 30% sequence ...

Proinsulin folding within the endoplasmic reticulum (ER) remains incompletely understood, but it is clear that in mutant INS gene-induced diabetes of youth (MIDY), progression of the (three) native disulfide bonds of proinsulin becomes derailed, causing insulin deficiency, β-cell ER stress, and onset of diabetes. Herein, we have undertaken a molecular dissection of proinsulin disulfide bond for...

The NH(2)-terminal somatomedin B (SMB) domain (residues 1-44) of human vitronectin contains eight Cys residues organized into four disulfide bonds and is required for the binding of type 1 plasminogen activator inhibitor (PAI-1). In the present study, we map the four disulfide bonds in recombinant SMB (rSMB) and evaluate their functional importance. Active rSMB was purified from transformed Esc...

Chromatographically homogeneous egg white lysozyme has been subjected under reduced pressure to 0.67-m.e.v. y-rays. At 37% destruction of enzymic activity, three inactive aggregates and one partially active fraction have been isolated by salt precipitation and chromatographic procedures. The aggregates, upon reduction with 2-mercaptoethanol and reaction with iodoacetic acid, give derivatives wi...

Human serum cholinesterase was digested with pepsin under conditions which left disulfide bonds intact. Peptides were isolated by high pressure liquid chromatography, and those containing disulfide bonds were identified by a color assay. Peptides were characterized by amino acid sequencing and composition analysis. Human serum cholinesterase contains 8 half-cystines in each subunit of 574 amino...

The majority of disulfide-linked cytosolic proteins are thought to be enzymes that transiently form disulfide bonds while catalyzing oxidation-reduction (redox) processes. Recent evidence indicates that reactive oxygen species can act as signaling molecules by promoting the formation of disulfide bonds within or between select redox-sensitive proteins. However, few studies have attempted to exa...

The pioneering studies of Anfinsen on ribonuclease have guided much of the research in the field of protein folding (Anfinsen et al., 1961). Anfinsen showed that, in vitro, reduced and denatured ribonuclease could refold into active enzyme with the formation of the appropriate disulfide bonds. These findings demonstrated that there was sufficient information in the primary amino acid sequence o...

The growth hormone receptor contains seven cysteine residues in its extracellular domain. The six in the growth hormone binding domain form disulfide bonds, and help the receptor to gain its correct three-dimensional structure. In this study we replaced the cysteine for serine and alanine residues and investigated their role in growth hormone receptor folding, dimerisation and signal transducti...

Disulfide bond formation is crucial for the biogenesis and structure of many proteins that are localized in the intermembrane space of mitochondria. The importance of disulfide bond formation within mitochondrial proteins was extended beyond soluble intermembrane space proteins. Tim22, a membrane protein and core component of the mitochondrial translocase TIM22, forms an intramolecular disulfid...

Disulfide bonds are generally not used to stabilize proteins in the cytosolic compartments of bacteria or eukaryotic cells, owing to the chemically reducing nature of those environments. In contrast, certain thermophilic archaea use disulfide bonding as a major mechanism for protein stabilization. Here, we provide a current survey of completely sequenced genomes, applying computational methods ...