We propose that the cellular burden of certain carcinogens may be mitigated by P-glycoprotein (P-gp), the putative drug effiux pump. In a series of multidrug resistant human breast cancer MCF-7 cells with increasing P-gp expression we examined this hypothesis using benzo(a)pyrene, a widely distributed environmental and dietary carcinogen. We found that multidrug resistant cells were cross-resis...

The review focuses on the unique spectral features of pyrene that can be utilized to investigate protein structure and conformation. Pyrene is a fluorescent probe that can be attached covalently to protein side chains, such as sulfhydryl groups. The spectral features of pyrene are exquisitely sensitive to the microenvironment of the probe: it exhibits an ensemble of monomer fluorescence emissio...

Several closely related branched structures related to the well-established benzyl ether dendrimers were tested as hosts for the removal of pyrene from water. Fluorescence spectroscopy based complexation studies showed that the first generation benzyl ether dendrimers removed on average 94 % of pyrene from a saturated aqueous solution after 30 min. By contrast, branched systems containing modif...

The degradation of pyrene, a polycyclic aromatic hydrocarbon containing four aromatic rings, by pure cultures of a Mycobacterium sp. was studied. Over 60% of [14C]pyrene was mineralized to CO2 after 96 h of incubation at 24 degrees C. High-pressure liquid chromatography analyses showed the presence of one major and at least six other metabolites that accounted for 95% of the total organic-extra...

a fast and simple modified quechers (quick, easy, cheap, rugged and safe) extraction method based on spiked calibration curves and direct sample introduction was developed for determination of benzo[a]pyrene (bap) in bread by gas chromatography-mass spectrometry single quadrupole selected ion monitoring (gc/ms-sq-sim). sample preparation includes extraction of bap into acetone followed by clean...

Pyrene derivatives can absorb onto the surface of carbon nanotubes and graphite particles through pi-pi interactions to functionalize these inorganic building blocks with organic surface moieties. Using single molecule force spectroscopy, we have demonstrated the first direct measurement of the interaction between pyrene and a graphite surface. In particular, we have connected a pyrene molecule...

Pyrene is a useful chromophore for monitoring the tertiary structure and folding of large RNAs. This unit describes the general preparation of a large RNA (>80 nucleotides in length) that has been site-specifically modified with pyrene at the 2'-position of an individual internal nucleotide. A protocol is provided for derivatizing a 2'-amino-RNA oligonucleotide with a suitably activated pyrene ...

The search of new organic emitters is receiving a strong motivation by the development ORTP materials. In present study we report on preparation, optical and photophysical characterization, both steady state time resolved techniques, two pyrene-functionalized cyclic triimidazole derivatives. Together with already reported mono-substituted derivative, di- tri-substituted members family have reve...

Understanding the potential for Polycyclic aromatic hydrocarbons (PAH) degradation by indigenous microbiota and the influence of PAHs on native microbial communities is of great importance for bioremediation and ecological evaluation. Various studies have focused on the bacterial communities in the environment where obvious PAH degradation was observed, little is known about the microbiota in t...

The metabolism of benzo(a)pyrene (BaP) by hepatic or cheek pouch epithelium microsomes obtained from Syrian golden hamsters which had been consuming an ethanol-containing liquid diet for 4 wk and from pair-fed controls was measured. Glutathione S-transferase activity with 1-chloro-2,4-dinitrobenzene or (+/-)-r-7,t-8-dihydroxy-t-9,10-epoxy-7,8,9,10-tetrahydrobenzo(a)pyrene as substrates was meas...