Protein disulfide isomerases comprise a large family of enzymes responsible for catalyzing the proper oxidation and folding of newly synthesized proteins in the endoplasmic reticulum (ER). Protein disulfide isomerase-related (PDIR) protein (also known as PDIA5) is a specialized member that participates in the folding of α1-antitrypsin and N-linked glycoproteins. Here, the crystal structure of t...

The manipulation of redox potential in secretory pathway by thiol reducing agents can be a strategy to improve the production levels of disulfide-bonded proteins including recombinant antibodies. Here we have studied the influence of cysteamine on viability and the production level of IgG4 in Sp2.0 cells. For this purpose, the recombinant Sp2.0 cells producing an anti CD33 IgG4, were subjected ...

The manipulation of redox potential in secretory pathway by thiol reducing agents can be a strategy to improve the production levels of disulfide-bonded proteins including recombinant antibodies. Here we have studied the influence of cysteamine on viability and the production level of IgG4 in Sp2.0 cells. For this purpose, the recombinant Sp2.0 cells producing an anti CD33 IgG4, were subjected ...

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...

The human immunodeficiency virus-1 (HIV-1) envelope glycoprotein 120 (gp120) binds to cell surface receptors and mediates HIV entry. Previous studies suggest the cell surface protein disulfide isomerase (PDI) might interact with disulfide bond(s) of gp120 and thus facilitate HIV-1 entry. In the present study, a kinetic trapping approach was used to capture the disulfide cross-linking intermedia...

AIMS Posttranslational formation of disulfide bonds is essential for the folding of many secreted proteins. Formation of disulfide bonds in a protein with more than two cysteines is inherently fraught with error and can result in incorrect disulfide bond pairing and, consequently, misfolded protein. Protein disulfide bond isomerases, such as DsbC of Escherichia coli, can recognize mis-oxidized ...

Correct formation of disulfide bonds is critical for protein folding. We find that cells lacking protein disulfide isomerases (PDIs) can use alternative mechanisms for correct disulfide bond formation. By linking correct disulfide bond formation to antibiotic resistance, we selected mutants that catalyze correct disulfide formation in the absence of DsbC, Escherichia coli's PDI. Most of our mut...

Human leukemia inhibitory factor (hLIF) is a multifunctional cytokine that is essential for maintaining the pluripotency of embryonic stem cells. hLIF may be also be useful in aiding fertility through its effects on increasing the implantation rate of fertilized eggs. Thus these applications in biomedical research and clinical medicine create a high demand for bioactive hLIF. However, productio...