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The study employs a two-step process, which helps in the identification of special monothiophosphate-modified aptamers (thioaptamers) that can bind to the hyaluronic acid binding domain (HBAD). These thioaptamers are shown to be extremely beneficial and can be used as a targeting agent during the delivery of therapeutic payloads.

Methionine sulfoxide reductases MsrA and MsrB are shown to be involved in the regulation of mitochondrial function. The results have shown that oxidative stress has contributed to mitochondrial dysfunction through oxidation of methionine residues in proteins located in different cellular compartments.

The structural and enzymological characterization of the human R194H mutant in longer form (lf) and short, cytokine-like, form of augmenter of liver regeneration (sfALR) is presented. The studies have shown the impact of the conservative R149H mutation on the stability of dimeric ALR.

The mechanism of the transfer of the sulfuryl moiety (-S[O.sub.3]) from PAPS (3' -phosphoadenosine 5' -phosphosulfate) to the 3' -hydroxyl of [E.sub.2], catalyzed by estrogen sulfotransferase (EST), is examined. The inhibition of estrogen sulfotransferase has no impact on the burst kinetics and has thus occurred after formation of the product central complex.

A radical-based molecular mechanism for the path of Ras-targeting thiopurines used in conjunction with redox agents is presented. The study results indicated that the oncogenic Ras in model cancer cell lines forms a complex with thioguanine nucleotide that is derived from long-term treatment with thiopurines.

UV-vis absorption, circular dichroism (CD), and fluorescence spectroscopy were employed to to study the binding interaction of thiazole Orange (TO) with double-, triple-, and quadruple-stranded forms of DNA. The findings suggested that TO staining might be useful for the detection of noncanonical structural motifs in genomic DNA.

The covalent modification observed in human copper-zinc superoxide dismutase (SOD1) was characterized to ascertain it as a novel heptasulfane bridge connecting the two Cys111 residues in the SOD1 homodimer. The modification might provide SOD1 with a toxic gain of function due to the catalytic ability of polysulfanes and polysulfides to catalyze the generation of reaction oxygen and sulfur species.

Stopped-flow absorption and isotope effect experiments were used to dissect the mechanism of formation of the enzyme cysteinyl persulfide intermediate in the reaction of a cysteine desulfurase (CD), CD0387 from Synechocystis sp. strain PCC 6803. The studies identified seven accumulating intermediates which were tentatively mapped onto the CD chemical mechanism.

Several studies are conducted to explain the chemical synthesis, as well as the impact of LNA-2-thiouridine on the different aspects of oligonucleotide binding to RNA. The complex is shown to highly enhance the stability, as well as the selectivity of the binding process.

Several studies are conducted to explain the significance of the various SufBCD Fe-S scaffold complex and the SufA protein in the biosynthesis of various iron-sulfur (Fe-S) clusters. The interaction between the complex and the clusters are shown to be extremely advantageous for the assembly system.

The article studies the iron-sulfur cluster of pyruvate formate-lyase activating enzyme (PFL-AE) in whole cells that undergoes cluster interconversion and a valence-localized in vitro, with only the [[4Fe-4S].sup.2+] cluster state. Findings reveal changes in cluster composition of PFL-AE in response to the redox state of the cell.

A novel combination of a molten globule-type C-terminal domain and an N-terminal domain with a fully folded regular tertiary structure possessed by human NFU also known as HIRIP5 implicated in cellular iron-sulfur cluster biosynthesis is described. Human NFU is found to be a functionally competent reducing agent for cysteinyl persulfide bond cleavage which release inorganic sulfide for incorporation into the ISU-bound [2Fe-2S] cluster, a reactivity that might be facilitated by the flexibility of the C-terminal domain.

A promiscuous sulfatase activity in nucleotide phosphodiesterase/pyrophosphatase from Xanthomonas axonopodis (NPP) is measured. The results have shown that active site contacts to substrate oxygen atoms that has not contacted the [Zn.sup.2+] ions has played an vital role in defining the selectivity of the enzymes.

The studies about the human NTPDase 2 activity, which is inactivated by membrane perturbation that disrupts interactions of the transmembrane domains and inhibited by p-chloro-mercuriphenylsulfonate (pCMPS), a sulfhydryl reagent are reported. The loss of the ATPase activity of human NTPDase 2 in the presence of pCMPS possibly results from the disturbance of both transmembrane domain interaction and its active site and is attenuated when the enzyme is cross-linked by glutaraldehyde.

The characterization of the human Urm1 and Saccharomyces cerevisiae Uba4 proteins, which have similar sequence as found in MOCS2A and MOCS3, two proteins essential for the biosynthesis of the molybdenum cofactor (Moco) in humans is reported. The functional similarities observed between Uba4 and MOCS3 demonstrate the evolutionary link between ATP-dependent protein conjugation and ATP-dependent cofactor sulfuration.

The impact of phenolsulfonphthalein and phenolphthalein on the mechanism of amyloid fibril formation is studied. The three-dimensional assembly of the polyphenol phenolsulfonphthalein is shown to play a very important role in inhibition of the amyloid formation activity.

The studies about mushroom tyrosinase which behaves as an external monooxygenase and catalyzes the asymmetric oxidation of organic sulfides to corresponding sulfoxides in the presence of suitable reducing agents, catechol are reported. The results provide insight into different experimental mechanism to increase enantioselectivity of tyrosinase activity.