A systematically varying series of monolayer-protected clusters (MPCs) was prepared by exposing small gold nanoparticles ( approximately 2 nm in diameter) to the following four adsorbates: n-octadecanethiol ( n - C18), 2-hexadecylpropane-1,3-dithiol ( C18C2), 2-hexadecyl-2-methylpropane-1,3-dithiol ( C18C3), and 1,1,1-tris(mercaptomethyl)heptadecane ( t - C18). The resultant MPCs were character...

Methionine oxidation leads to the formation of S- and R-diastereomers of methionine sulfoxide (MetSO), which are reduced back to methionine by methionine sulfoxide reductases (MSRs) A and B, respectively. MSRBs are classified in two groups depending on the conservation of one or two redox-active Cys; 2-Cys MSRBs possess a catalytic Cys-reducing MetSO and a resolving Cys, allowing regeneration b...

CalDAG-GEFI, a guanine nucleotide exchange factor activating Rap1, is known to play a key role in Ca2+-dependent glycoprotein (GP)IIb/IIIa activation and platelet aggregation. Although inhibition of CalDAG-GEFI could be a potential strategy for antiplatelet therapy, no inhibitor of this protein has been identified. In the present study, phenylarsine oxide (PAO), a vicinal dithiol blocker, poten...

Acute insult to the myocardium is associated with substantial loss of cardiomyocytes during the process of myocardial infarction. In this setting, apoptosis (programmed cell death) and necrosis may operate on a continuum. Because the latter is characterized by the loss of sarcolemmal integrity, we propose that an appropriately labeled tracer directed at a ubiquitously present intracellular moie...

Biosynthesis of the dithiolopyrrolone antibiotic holomycin in Streptomyces clavuligerus involves the closure of a pair of enethiols to a cyclic disulfide. We have shown that the dithiol oxidase HlmI is responsible for the disulfide formation and this enzyme also plays a role in self-protection. In the present study, we examine how S. clavuligerus deals with the proposed toxic dithiol intermedia...

The fields of molecular electronics and self-assembly have the potential to revolutionize the way electronic devices are constructed. There are many high-level designs of self-assembling systems that, given the proper components, could be used to construct such devices, and there are many low-level components that have been experimentally validated and could be used in self-assembling systems. ...

Detailed understanding and control of the intermolecular forces that govern molecular assembly are necessary to engineer structure and function at the nanoscale. Liquid crystal (LC) assembly is exceptionally sensitive to surface properties, capable of transducing nanoscale intermolecular interactions into a macroscopic optical readout. Self-assembled monolayers (SAMs) modify surface interaction...

Platelet function is influenced by the platelet thiol-disulfide balance. Platelet activation resulted in 440% increase in surface protein thiol groups. Two proteins that presented free thiol(s) on the activated platelet surface were protein-disulfide isomerase (PDI) and glycoprotein 1balpha (GP1balpha). PDI contains two active site dithiols/disulfides. The active sites of 26% of the PDI on rest...

Glutaredoxins (Grxs) are redox proteins that use glutathione ((γ)Glu-Cys-Gly; GSH) as a cofactor. Plasmodium falciparum has one classic dithiol (CXXC) glutaredoxin (glutaredoxin 1; PfGrx1) and three monothiol (CXXS) Grx-like proteins (GLPs), which have five residue insertions prior to the active-site Cys. Here, the crystal structure of PfGrx1 has been determined by the sulfur single-wavelength ...

Insulin stimulates phosphorylation of a tyrosine residue(s) on a 15-kDa protein (p15), and the cytosolic phosphorylated protein (pp15) accumulates only when 3T3-L1 adipocytes are treated with phenylarsine oxide. It has been shown previously that phenylarsine oxide, an agent that complexes vicinal dithiols, interrupts signal transmission from the insulin receptor to the glucose transport system....