Children suffering from cystinosis, a genetic disease characterized by high levels of lysosomal cystine, are currently being treated with cysteamine to lower the cystine levels in their cells. In fibroblasts from these patients, cysteamine and its disulfide, cystamine, are equally effective in lowering cystine levels. We recently reported that pantethine, a dietary precursor of coenzyme A, depl...

DISULFIDE bonds in proteins—how these bonds are formed, how they are cleaved, and how they participate in protein folding—have become my passion over the past 25 years. During this period, the discoveries in my lab in this very biochemical realm have come largely from genetic approaches. Many factors have influenced the pace of our progress, including at times ignorance of certain biochemical d...

Objective: Lung cancer has a poor prognosis. Thiol groups with high antioxidant capacity are converted to disulfide bonds through biochemical reactions that neutralize different oxidant compounds. The thiol-disulfide (SH-SS) homeostasis significant effects on cell mechanisms, transcription, and apoptosis. Here we present the prognostic role of dynamic SH-SS in patients operated for NSCLC. Mater...

In this experiment, the chemical composition of the essential oils obtained from Ferula assa-foetida oleo-gum resin collected from two different sites of Yazd province (Tabas and Yazd) in the center of Iran, were identified. The gas chromatography mass-spectroscopy (GC/MS) data showed that the qualitative composition of the components appeare...

Protein disulfide isomerase (PDI) catalyzes the rearrangement of nonnative disulfide bonds in the endoplasmic reticulum of eukaryotic cells, a process that often limits the rate at which polypeptide chains fold into a native protein conformation. The mechanism of the reaction catalyzed by PDI is unclear. In assays involving protein substrates, the reaction appears to involve the complete reduct...

Thioredoxin (Trx) from Escherichia coli was compared with bovine protein disulfide-isomerase (PDI) for its ability to catalyze native disulfide formation in either reduced or randomly oxidized (scrambled) ribonuclease A (RNase). On a molar basis, a 100-fold higher concentration of Trx than of PDI was required to give the same rate of native disulfide formation measured as recovery of RNase acti...

CyDisCo is a system facilitating disulfide bond formation in recombinant proteins in the cytoplasm of Escherichia coli. Previously we screened for soluble expression of single chain antibody fragments (scFv) in the cytoplasm of E. coli in the presence and absence of CyDisCo, with >90% being solubly expressed. Two scFv, those derived from natalizumab and trastuzumab, were solubly produced in hig...

Chicken liver fatty acid synthase is rapidly inactivated and cross-linked at pH 7.2 and 8.0 by incubation with low concentrations of common biological disulfides including glutathione disulfide, coenzyme A disulfide, and glutathione-coenzyme A-mixed disulfide. Glutathione disulfide inactivation of the enzyme is accompanied by the oxidation of a total of 4-5 enzyme thiols per monomer. Only one g...

The identification of disulfide bonds provides critical information regarding the structure and function of a protein and is a key aspect in understanding signaling cascades in biological systems. Recent proteomic approaches using digestion enzymes have facilitated the characterization of disulfide-bonds and/or oxidized products from cysteine residues, although these methods have limitations in...

A prediction method of protein disulfide bond based on support vector machine and sample selection is proposed in this paper. First, the protein sequences selected are encoded according to a certain encoding, input data for the prediction model of protein disulfide bond is generated; Then sample selection technique is used to select a portion of input data as training samples of support vector ...