The asymmetric unit of the title salt adduct, C(6)H(13)N(2)O(+)·C(8)H(5)O(4) (-)·C(8)H(6)O(4), comprises one isonipecotamide cation, a hydrogen phthalate anion and a phthalic acid adduct mol-ecule. These form a two-dimensional hydrogen-bonded network through head-to-tail cation-anion-adduct mol-ecule inter-actions which include a cyclic heteromolecular amide-carboxyl-ate motif [graph set R(2) (...

To analyse the electrocatalytic oxidation of carbon monoxide by Rh porphyrins, we isolated a CO-adduct of Rh octaethylporphyrin, and examined its properties and reactivity by IR, NMR, and X-ray crystallographic analyses. The results indicate that the CO adduct of Rh octaethylporphyrin is vulnerable to nucleophilic attack by H2O. The CO-adduct was easily oxidized by an electron acceptor (1,4-nap...

A major and previously undetected carcinogen-DNA adduct was found in the livers of rats given N,N-dimethylnitrosamine or 1,2-dimethylhydrazine. This adduct, which accounted for 55% of the total methyl residues in DNA at 72 hours after carcinogen treatment, was chromatographically identical to a synthetic purine ring-opened derivative of 7-methylguanine and could be released from the isolated he...

Acrolein reacted with deoxyguanosine at pH 7 and 37 degrees to give three major products, Adducts 1 to 3, which were separated by high-performance liquid chromatography. They were identified by their ultraviolet, mass, and nuclear magnetic resonance spectra, by the spectra of the corresponding guanine derivatives, and by chemical transformations. Adducts 1 and 2 were two rapidly equilibrating d...

The reaction of purified bovine mitochondrial cytochrome c oxidase (CcO) and hydrogen peroxide was studied using the ESR spin-trapping technique. A protein-centered radical adduct was trapped by 5, 5-dimethyl-1-pyrroline N-oxide and was assigned to a thiyl radical adduct based on its hyperfine coupling constants of aN = 14.7 G and abetaH = 15.7 G. The ESR spectra obtained using the nitroso spin...

Brown bullheads (Ictalurus nebulosus) were sampled from sites in the Buffalo and Detroit Rivers where fish are exposed to high levels of sediment bound polycyclic aromatic hydrocarbons, and suffer from an elevated frequency of liver cancer. DNA was isolated from the livers of these wild fish and from control specimens which were raised in clean aquariums. DNA was enzymatically digested to norma...

The formation of adducts of benzo(a)pyrene metabolites on DNA was investigated in endometrial tissue from humans, hamsters, mice, and rats. anti-Benzo(a)pyrene-7,8-diol-9,10-epoxide was the predominant adduct identified in all the species studied. The amount of (+)-anti-benzo(a)pyrene-7,8-diol-9,10-epoxide bound to DNA from human endometrium was approximately 3 times higher than to DNA from ham...

Nitrated pyrenes are environmental pollutants and potent mutagens in the Salmonella reversion assay. In this study reversion induction by 1-nitropyrene and 1,8-dinitropyrene in Salmonella typhimurium TA1538 and mutation induction by 1-nitropyrene in Chinese hamster ovary (CHO) cells were related to the extent of metabolism and DNA adduct formation. In suspension cultures of Salmonella typhimuri...

We are interested in devising techniques which will allow us to measure and quantitate exposure to chemical carcinogens and which eventually can be used in risk analysis with humans. Our recent research with HPLC/fluorescence has demonstrated that we can detect, identify, and quantitate the binding of benzo(a)pyrene (BaP) with DNA of mouse skin. The technique not only allows femtomole amounts o...

Nonenzymatic glycation of proteins has been implicated in various diabetic complications and age-related disorders. Proteins undergo glycation at the N-terminus or at the epsilon-amino group of lysine residues. Glycation of proteins proceeds through the stages of Schiff base formation, conversion to ketoamine product and advanced glycation end products. Gramicidin S, which has two ornithine res...