The ability to bias chemical reaction pathways is a fundamental goal for chemists and material scientists to produce innovative materials. Recently, two-dimensional materials have emerged as potential platforms for exploring novel mechanically activated chemical reactions. Here we report a mechanochemical phenomenon in graphene oxide membranes, covalent epoxide-to-ether functional group transfo...

The major adduct formed on acid hydrolysis of calf thymus DNA which has been reacted with 8,9-dichloro-8,9-dihydroaflatoxin B1, a chemical model of the ultimate carcinogen 8,9-dihydro-8,9-epoxyaflatoxin B1 (AFB1-epoxide), has been characterized by proton nuclear magnetic resonance and fast atom bombardment mass spectroscopy. This adduct has been identified as an N7-substituted guanine adduct an...

Epoxide hydrolases (EH, EC 3.3.2.3) have been proposed to be key enzymes in the biosynthesis of polyether (PE) ladder compounds such as the brevetoxins which are produced by the dinoflagellate Karenia brevis. These enzymes have the potential to catalyze kinetically disfavored endo-tet cyclization reactions. Data mining of K. brevis transcriptome libraries revealed two classes of epoxide hydrola...

A liver microsomal protein, previously referred to as preneoplastic antigen, from hyperplastic nodules of rats fed a diet containing 2-acetylaminofluorene has been identified as the enzyme epoxide hydrase [glycol hydro-lyase (epoxideforming), EC 4.2.1.63]. Purified preneoplastic antigen from hyperplastic nodules and purified rat liver microsomal epoxide hydrase are immunochemically identical on...

The ability to bias chemical reaction pathways is a fundamental goal for chemists and material scientists to produce innovative materials. Recently, two-dimensional materials have emerged as potential platforms for exploring novel mechanically activated chemical reactions. Here we report a mechanochemical phenomenon in graphene oxide membranes, covalent epoxide-to-ether functional group transfo...

Microsomal epoxide hydrolase plays a dual role in the activation and detoxification of carcinogenic compounds. Two polymorphic sites have been described in exons 3 and 4 of the microsomal epoxide hydrolase gene that change tyrosine residue 113 to histidine (Tyr113His) and histidine 139 to arginine (His139Arg), respectively. The exon 3 polymorphism reduces enzyme activity by approximately 50%, w...

In nipple aspirates of breast fluid from nonpregnant healthy women, cholesterol and cholesterol epoxide levels were determined with gas-liquid chromatography and mass spectrophotometric techniques. Cholesterol levels were found to be elevated above plasma levels averaging 2200 +/- 1995 (S.D.) mg/dl and showing progressive increases in mean breast fluid cholesterol levels with advancing age, ave...

Haliangicin is a beta-methoxyacrylate-type polyene antibiotic isolated from the unique marine myxobacterium Haliangium ochraceum. A further investigation of the extract of this microorganism has resulted in the isolation of haliangicin as well as its geometrical isomers. The configuration of the epoxide in haliangicin, which was unknown previously, was determined in this study. The planar struc...

Glutathione S-transferase activities have been identified in the small intestine of the rat. Thrree activities obtained with p-nitrobenzyl chloride (aralkyl), 1,2-epoxy-3(p-nitrophenoxy)propane (epoxide), and ethacrynic acid (alkene) as substrates were present in significant amounts. Gel filtration indicated an elution volume for the intestinal transferase activities that was similar to those a...

K-region epoxides of benz[a] anthracene, dibenz[a,h] anthracene, and 3-methylcholanthrene have been found to be toxic and more active in producing malignant transformation of cells derived from mouse prostate than their respective parent hydrocarbons and K-region dihydrodiols and phenols. The data support the view that metabolism of these polycyclic hydrocarbons is a prerequisite for their biol...