The intestinal bioavailability and biotransformation of 3-hydroxybenzo(a)pyrene, a major metabolite of benzo(a)pyrene in many animal species, was investigated in an in situ isolated intestinal preparation from the channel catfish, and in vitro with preparations of catfish intestine and blood. 3-Hydroxybenzo(a)pyrene was a good substrate for adenosine 3'-phosphate 5'-phosphosulfate (PAPS)-sulfot...

Through binding and fluorescence studies of oligonucleotides covalently attached to a pyrene group via one carbon linker at the sugar residue, we previously found that pyrene-modified RNA oligonucleotides do not emit well in the single-stranded form, yet the attached pyrene emits with a significantly high quantum yield upon binding to a complementary RNA strand. In sharp contrast, similarly mod...

The transfer of pyrene between high density lipoproteins was studied as a model of lipid exchange. When high density lipoprotein containing pyrene was mixed with unlabeled lipoprotein, pyrene excimer fluorescence decreased with a half-time of approximately 3 ms. The rate of pyrene transfer was invariant over a 100-fold range of unlabeled lipoprotein concentrations. Since a decrease in excimer f...

Metabolic activity, particularly conjugation, was examined in fish by analyzing pyrene (a four-ring, polycyclic aromatic hydrocarbon) metabolites using high-performance liquid chromatography (HPLC) with fluorescence detector (FD), a mass spectrometry (MS) system, and kinetic analysis of conjugation enzymes. Fourteen fresh water fish species, including Danio rerio and Orizias latipes, were expos...

Twelve workers from a coke plant in The Netherlands participated in an intensive skin monitoring programme combined with personal air sampling and biological monitoring during five consecutive eight hour workshifts. The purpose of the study was to make a quantitative assessment of both the dermal and respiratory intake of polycyclic aromatic hydrocarbons (PAHs). Pyrene was used as a marker comp...

The binding and fluorescence properties of complementary RNA sequences attached to different numbers of pyrenes via one carbon linker at the 2'-O-positions have been investigated. Upon hybridization of the pyrene-modified RNA sequences, the modified RNA duplexes with normal thermal stability are formed, and the pyrene arrays are assembled in an inter-strand manner. Because hypochromic effects i...

Pyrene is a very resistant polycyclic aromatic hydrocarbon (PAH) with four benzene rings that survives in the environment. This study was aimed at investigating tolerance of earthworms soil contaminated pyrene. The studies were performed by employing gathered from shady regions adjacent to sewage ponds as pyrene degraders eradicate soil. Numerous factors affecting degradation efficiency explore...

The pi-pi interaction between pyrene molecules and single-walled carbon nanotubes (SWNTs) or multi-walled carbon nanotubes (MWNTs) was studied by fluorescence, FTIR, Raman spectroscopy and molecular simulation. The carbon nanotubes were incubated in pyrene solution and dried for characterization. A broadband fluorescence emission at 463 nm of the incubated samples was observed, which is similar...

In this study, we obtained over 4,000 transposon mutants of Mycobacterium vanbaalenii PYR-1 and analyzed one of the mutants, 8F7, which appeared to lose its ability to degrade pyrene while still being able to degrade fluoranthene. This mutant was identified to be defective in nidA, encoding an aromatic ring-hydroxylating oxygenase (RHO), known to be involved in the initial oxidation step of pyr...

The metabolism of benzo(a)pyrene in cultured human colon has been investigated. Nontumorous colonie tissue was collected at the time of either surgery or "immediate autopsy" from patients with or without colonie cancer. After 24 hr in culture the expiants were exposed to [3H]benzo(a)pyrene for another 24 hr and the binding to cellular DMA and protein was measured. Two adducts, formed between be...