Purine nucleoside phosphorylase (PNP) deficiency in humans is associated with a severe T cell immunodeficiency. To understand further and exploit this T cell lymphospecificity, we have compared the cytotoxicities and metabolism of deoxyguanosine, the cytotoxic substrate of PNP and of arabinosylguanine, a deoxyguanosine analogue that is resistant to PNP cleavage, in T cell (8402) and B cell (839...

A set of three 14mer oligodeoxyribonucleotides of sequence d(5'-CTATGGCCTCAG*CT-3'/3'-GATACCGGAGTCGA-5') containing G* variants either as 2'-deoxyguanosine phosphate (unmodified), N7-cyanoborane 2'-deoxyguanosine phosphate (base-modified) or 2'-deoxyguanosine boranophosphate (backbone-modified) were synthesized by template-directed primer extension. Both the N7-cyanoborane 2'-deoxyguanosine tri...

Aging and exposure to sunlight are two major factors in the deterioration of skin function. In this study, thirty-six fixed human skin samples from sun-exposed and unexposed areas from young and old individuals were used to evaluate the localization of oxidative stress according to levels and distribution of 8-hydroxy-2'-deoxyguanosine and N(ε)-(carboxymethyl)lysine in samples using immunohisto...

INTRODUCTION AND OBJECTIVES Heart failure is associated with increased free radical production, which leads to a state of oxidative stress. Known markers of oxidative stress include 8-hydroxy-2'-deoxyguanosine, which reflects oxidative damage to DNA, and lipid peroxidation, which can be used to quantify damage to lipid-rich structures. The aims of this study were to compare 8-hydroxy-2'-deoxygu...

trans-4-Hydroxy-2-hexenal (t-4HH), a reactive metabolite isolated from the pyrrolizidine alkaloid senecionine, and trans-4-hydroxy-2-nonenal (t-4HN), a product of lipid peroxidation, reacted nonenzymatically with deoxyguanosine at pH 7.4 at 37 degrees C in vitro with each compound yielding two pairs of diastereomeric adducts. Adducts were isolated using reverse phase high-performance liquid chr...

We have computed the total energy surface as a function of two important torsion angles of the carcinogen N-2-acetylaminofluorene (AAF) bonded to the carbon C8 of deoxyguanosine using the semi-empirical quantum mechanical method, MNDO. One global minimum and one local minimum are found separated by an appreciable barrier. The equilibrium geometries show the rearrangement of AAF and the base con...

The preparation of oligonucleotides containing 8-bromo-2'-deoxyguanosine is described. Substitution of G by 8-bromoguanine on an alternating CG decamer stabilizes the Z-form in such a way that the B-form was not observed. Melting temperatures showed that duplexes in which 8-bromo-2'-deoxyguanosine paired with natural bases were much less stable.

Oxidation of 2’-deoxyguanosine (dG) results in the major two-electron product 8oxo-7,8-dihydro-2’-deoxyguanosine (dOG) that can undergo further oxidation to other products. One such product is 5-guanidinohydantoin (dGh) that is highly mutagenic and has been found in vivo. The ring architecture of dGh is similar to allantoin, an oxidation product of uric acid. Allantoin establishes equilibrium b...

A selective synthesis of N2-deoxyguanosine adducts derived from 4-aminobiphenyl (ABP) is described. The reactions of O2-trifluoromethylsulfonyl-O6-allyl-3',5'-O-bis(tert-butyldimethyl silyl)-2'- deoxyxanthosine with 3-amino-4-acetaminobiphenyl and 4-hydrazinobiphenyl, respectively, are the key steps. Successive removal of the protecting groups from the protected adducts leads to the free adduct...