Disease relevance of pyrene

• A mutant strain of Beijerinckia, after growth with succinate plus biphenyl, contains an enzyme system that oxidizes benzo [a] pyrene and benzo [a] anthracene to mixtures of vicinal dihydrodiols [1].
• Photosensitized killing of cultured fibroblasts from patients with peroxisomal disorders due to pyrene fatty acid-mediated ultraviolet damage [2].
• Reduced survival was observed in cells deficient in plasmalogens (rhizomelic chondrodysplasia punctata) and in cells deficient in peroxisomal fatty acid oxidation (bifunctional enzyme deficiency), which accumulated pyrene-fatty acids [2].
• This paper describes a method, designated "receptor-dependent photosensitization," by which the receptor-mediated endocytosis of low density lipoprotein (LDL) can be used to deliver a photosensitizing agent, pyrene, to cultured human and animal cells [3].
• Pyrene did not induce either DNA adducts or lung adenomas at any of the doses examined [4].

Psychiatry related information on pyrene

• The gas-phase photochemical reaction of pyrene with nitrogen dioxide was examined in a quartz vessel with various reaction times and temperatures [5].
• An effect of alcohol consumption and the use of medication on the toxicokinetics of pyrene was not found [6].

High impact information on pyrene

• Here we test this idea by using a pyrene nucleoside triphosphate (dPTP) in which the fluorescent 'base' is nearly as large as an entire Watson-Crick base pair [7].
• The outer (exofacial) and inner (endofacial) leaflets of the erythrocyte membrane differ in lipid composition, and recent studies using a group of membrane-impermeant pyrene fluorophores have demonstrated that the lipid fluidity of the outer leaflet exceeds that of the inner [8].
• In pyrene actin assay, Cdc42 enhanced VirG-stimulating actin polymerization by N-WASP-actin-related protein (Arp)2/3 complex [9].
• X-linked adrenoleukodystrophy fibroblasts accumulated pyrene-fatty acids and showed increased UV sensitivity only when exposed to longer-chain pyrene fatty acids [2].
• Viscosity measurements and studies on the polymerization kinetics of pyrene-labeled actin showed that hsc70 increased the capping activity of cap32/34 up to 10-fold, whereas hsc70 alone had no effect on actin polymerization [10].

Chemical compound and disease context of pyrene

• BeP clearly showed the least toxicity followed by pyrene and anthracene [11].
• The uptake of a fluorescent derivative of a fatty acid (FDFA), 12-(1-pyrene) dodecanoic acid (P12) by murine erythroleukemia (MEL) cells was studied [12].
• The well-characterized integral membrane protein lactose (lac) permease from Escherichia coli was reconstituted together with trace amounts (molar fraction X = 0.005 of the total phospholipid) of different pyrene-labeled phospholipid analogs into 1-palmitoyl-2-oleoyl-sn-glycero-3-sn-glycero-3-phospho-rac'-glycerol (POPG) liposomes [13].
• Microcosms inoculated with the Mycobacterium sp. showed enhanced mineralization, singly and as components in a mixture, of 2-methylnaphthalene, phenanthrene, pyrene, and benzo[alpha]pyrene [14].
• Mycobacterium sp. strain Pyr-1 cells, which were grown to the stationary phase in media with and without pyrene, were centrifuged and resuspended in a medium containing 1-nitropyrene [15].

Biological context of pyrene

• Pyrene excimer fluorescence and resonance energy transfer studies on the labeled mutant troponin C reveal a Ca(2+)-induced increase in distance between the two cysteines [16].
• On the other hand, the results of the quenching study with KI, excimer fluorescence, and polarization measurements of pyrene-labeled membranes suggested an increase of membrane fluidity on addition of KCl to medium [17].
• To probe adriamycin-phospholipid interactions, the effects of this cytotoxin on the hydrolysis of a pyrene-labeled acidic alkyl-acyl phospholipid analog 1-octa-cosanyl-2-(6-pyren-1-yl)hexanoyl-sn-glycero-3-phos p hatidylmethanol (C28-O-PHPM) by porcine pancreatic phospholipase A2 (PLA2) were studied [18].
• Although the pyrene tag weakens protein binding, unbiased protein-RNA association constants were obtained in competition experiments with untagged RNA [19].
• These results provide important information regarding the role of lipids on membrane protein folding and conformation as well as demonstrate the usefulness of a pyrene-based system in studying the forces that govern interhelical packing [20].

Anatomical context of pyrene

• Second, as measured with pyrene-labeled yeast actin, but not with intrinsic fluorescence, there is an overshoot in the fluorescence that has not been observed with skeletal muscle actin under the same conditions [21].
• Toward this end, a monoclonal antibody against an antigen on the surface of T lymphocytes was covalently attached to liposomes containing a phototoxic drug, pyrene, bound to the lipid bilayer [22].
• When a pyrene derivative of sphingomyelin was introduced into the lysosomes of cultured fibroblasts from a type A NPD patient by using apolipoprotein E-mediated endocytosis, only approximately 6% of the delivered substrate was degraded [23].
• The interaction of actin filaments and monomers with human serum was studied by following the kinetics and extent of the depolymerization of pyrene-labeled F-actin and by analysis of serum proteins adhering to immobilized actin monomers [24].
• These experiments suggest that thehydroxylase is important in determining the sensitivity of epithelial cells to the cytotoxic action of benzo (a) pyrene, but other factors may also modulate this sensitivity [25].

Associations of pyrene with other chemical compounds

• The chemotherapeutic agent 6-mercaptopurine was previously shown to inhibit the binding of 7r,8t-dihydroxy-9,10t-oxy-7,8,9,10-tetrahydro-benzo(a) pyrene (BPDE-I) to DNA in Chinese hamster ovary cells [26].
• Under similar conditions adriamycin also enhanced the rate of hydrolysis of the pyrene-labeled diacyl lipid 1-palmitoyl-2-(pyren-1-yl)hexanoyl-sn-glycero-3-phosphatidylgly cer ol and inhibited the hydrolysis of PLA2 on the phosphatidylcholine derivative [18].
• The rate of increase in pyrene fluorescence matches the rate of increase in tryptophan fluorescence [27].
• The Stern-Volmer quenching constants of pyrene-ATPase fluorescence were 10 times lower than the constant obtained for acrylamide quenching of the fluorescent adduct of pyrene-maleimide-cystein used as a control, indicating that the pyrene moiety of the probe was considerably shielded from the medium solvent when covalently attached to the ATPase [28].
• Using CE-gamma-CD-mediated transfer, we introduced hydrophobic pyrene-labeled phosphatidylserine to the plasma membrane of fibroblast cells and followed their distribution with time [29].

Gene context of pyrene

• To monitor binding of tropomyosin to yeast actin, we mutated S235 to C and labeled the actin with pyrene maleimide at both C235 and the normally reactive C374 [30].
• 2. When PyrPC-rHDL was incubated with HDL3 in the presence of PLTP, a rapid decline of the pyrene excimer/monomer fluorescence ratio (E/M) occurred, demonstrating that PLTP induced mixing of the surface lipids of PyrPC-rHDL and HDL3 [31].
• Adduction of the human N-ras codon 61 sequence with (-)-(7S,8R,9R,10S)-7,8-dihydroxy-9,10-epoxy-7,8,9,10-tetrahydrobenzo[a] pyrene: structural refinement of the intercalated SRSR(61,2) (-)-(7S,8R,9S,10R)-N6-[10-(7,8,9,10- tetrahydrobenzo[a]pyrenyl)]-2'-deoxyadenosyl adduct from 1H NMR [32].
• In occupationally exposed populations CYP2E1 and GSTM1 appear to play an important role in the metabolism of pyrene and naphthalene [33].
• Pyrene excimer fluorescence of yeast alcohol dehydrogenase: a sensitive probe to investigate ligand binding and unfolding pathway of the enzyme [34].

Analytical, diagnostic and therapeutic context of pyrene

• Fluorescence titrations showed that an increase in salt concentration not only decreased the binding constant of troponin to Tm but also decreased the magnitude of the total pyrene fluorescence change [35].
• In a low ionic strength buffer the absence of filaments was confirmed by electron microscopy, ultracentrifugation, and the fluorescence of pyrene-labeled actin [36].
• Trypsin digestion of pyrene-labeled aminotransferase, followed by gel filtration and "fingerprint" analysis, revealed the presence of only one peptide tagged with the fluorescent probe [37].
• Fluorescence, UV-vis absorption, and circular dichroism measurements indicate that in our studies pyrene pendants attached themselves along PGA in a clustered manner [38].
• A ratiometric fluorescent biosensor for Hg2+ is constructed from the MerR protein and a duplex DNA containing a pyrene excimer [39].

References