Global ETD Search
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Showing 1 to 20 of 38 for “"Cytochromes P450"”.
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Mechanistic Studies of Two Steroidogenic Cytochromes P450, CYP17A1 and CYP21A2
Human CYP17A1 (P450c17 or 17alpha-hydroxylase/17,20-lyase) is a member of the P450 superfamily of proteins. This enzyme is responsible for hydroxylating the 17-position of pregnenolone or progesterone and cleaving the 17,20-carbon,carbon-bond of its hydroxylated products, which leads to the …
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Investigating the evolution of cytochromes P450 involved in GA biosynthesis
… kaurene oxidases (KO), which are multifunctional cytochromes P450 that catalyze oxidation at the C4α methyl, converting ent-kaurene to ent -kaurenoic acid, an early step in gibberellin phytohormone biosynthesis. Arabidopsis produces no labdane-related diterpenoids other than gibberellins, whereas …
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Mechanistic investigation of human cytochromes P450 involved in hormone biosynthesis
CYP17A1 and CYP19A1 are the key cytochromes P450 involved in steroidogenesis. Mutations causing hypo- or hyper-activation of both these enzymes results in diseased states, including cancers. In addition to carrying out mono-oxygenation reactions, both CYP17A1 and CYP19A1 also catalyze carbon-carbon …
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The Membrane Topology of the Microsomal Cytochromes P450: Interfacial Characterization of Protein Structure
… used to monitor the binding of two truncated P450s with a phosphatidylcholine supported lipid bilayer. The data has been fit to a kinetic model that incorporates a semi-empirical available surface function to account for the effect of steric interactions between pre-adsorbed molecules. The …
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Engineering Enhanced Cytochromes P450: Understanding Thermostability and Mechanism Through Rational Design and Directed Evolution
Although random and rational approaches for protein engineering are often used as separate approaches, this work has demonstrated the benefits of combining these approaches. Through the use of both methods a better understanding of thermostability, catalytic mechanism and substrate specificity was …
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Microarray and molecular genetic analysis of aberrant splicing in human drug metabolizing cytochromes P450 CYP2D6 and CYP2B6
… of alternative splicing within the Cytochrome P450 enzymes 2D6 and 2B6, mapping of the most common splice variants and to draw connections to certain single nucleotide polymorphisms (SNPs) and alleles. For both enzymes a splicing sensitive microarray was developed. The microarray was produced …
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Expression différentielle des cytochromes P450 et des glutathion S-transférases en réponse au spinosad chez le doryphore de la pomme de terre
… l’expression de transcrits codant pour les CYP450s et les GSTs, des molécules précédemment liées à la réponse aux insecticides. De plus, l’utilisation de l’ARNi afin de diminuer l’expression de certains transcrits et d’étudier l’impact phénotypique d’une telle modification chez le doryphore de …
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Capture and Characterization of Dioxygen Reactive Intermediates in CYP51 Catalysis
The cytochromes P450 (CYPs) are a superfamily of biological catalysts that are ubiquitous throughout the biological domain. CYPs are heme-b containing monooxygenases which oxidize substrates with the help of accessory redox partners. CYP substrates include endogenous compounds required for many …
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Phytochemical Investigation and Drug Interaction Potential of <em>Cyanotis vaga</em>
… about its effect on the drug metabolizing enzyme Cytochromes P450 to predict its interaction with concomitantly used medications. In this study, eight ecdysteroids were isolated from <em>C. vaga</em>, including two previously reported from <em>C. vaga</em>. The additional six ecdysteroids were …
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Transcriptional regulation of basal and phenobarbital-mediated expression of rat cytochrome 2B genes
Cytochromes P450 2B1 and 2B2 (CYP2B1 and CYP2B2) are well known phenobarbital inducible genes in rat liver. Potential transcriptional regulatory elements in the proximal promoter regions of rat CYP2B genes were analyzed by transfection in HepG2 cells and by binding of nuclear proteins. Deletion of …
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Prediction of CYP3A4 metabolic activity from whole genome RNA-seq data with feature selection machine learning methods
CYP3A4, one of the isozyme of the cytochromes P450 (CYPs), contributes significantly to drug clearance and drug-drug interactions. The goals of this project are to identify hepatically-expressed genes that are associated with CYP3A4 metabolic activity in human liver tissue and to predict CYP3A4 …
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Investigation of cytochrome P450s in the biosynthesis of rice phytoalexins
… group of enzymes in diterpenoid biosynthesis are cytochromes P450 (CYPs) which catalyze various tailoring reactions on LRD olefins to produce bioactive diterpenoids. Intriguingly, two biosynthetic gene clusters (BGCs), composed of CYPs and upstream cyclases dedicated to LRD production, have been …
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Vliv cytochromu b5 na enzymovou kinetiku hydroxylace Sudanu I lidským cytochromem P450 1A1
Cytochromes P450 are the major xenobiotics converting enzymes. They are classified as mixed function monooxygenases (MFO). Isoform 1A1 is a extrahepatic form found mainly in the lung and other tissues. It is strongly induced by polycyclic aromatic hydrocarbons and their derivatives via the Ah …
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Elucidation of gene clusters underlying withanolide biosynthesis in ashwagandha
… with in vitro enzyme assays. We discover two cytochromes P450 (CYP87G1 and CYP749B2) and a short-chain dehydrogenase (SDH2) responsible for formation of the lactone ring on the sterol side chain, a key chemical feature of withanolides. Two additional P450s (CYP88C7 and CYP88C10) and a …
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Biomimetic emulators of high potential peroxygenases: Implications in bioremediation and metabolic studies
… and to predict the drug metabolism by cytochromes P450. The biomimetic catalysts, for the studied cases, also proved to be much more efficient than the corresponding enzymes.
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Exploration of [2+2+2] cyclotrimerisation reactions of alkynes. A new methodology for the synthesis of small molecules to probe biological systems
… cell lines are known to express extra-hepatic cytochromes P450 enzymes, it is possible that these are involved in generating cytotoxic metabolites that may damage DNA.
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Exploration of [2+2+2] cyclotrimerisation reactions of alkynes. A new methodology for the synthesis of small molecules to probe biological systems
… cell lines are known to express extra-hepatic cytochromes P450 enzymes, it is possible that these are involved in generating cytotoxic metabolites that may damage DNA.
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Exploration of [2+2+2] cyclotrimerisation reactions of alkynes. A new methodology for the synthesis of small molecules to probe biological systems
… cell lines are known to express extra-hepatic cytochromes P450 enzymes, it is possible that these are involved in generating cytotoxic metabolites that may damage DNA.
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The Effects of Ethanol and Nicotine on Hepatic and Brain CYP2 Family Enzymes in African Green Monkeys
Cytochromes P450 (CYPs) metabolize a vast array of xenobiotics, including many drugs and toxins. Induction or downregulation of the CYPs can have important consequences such as changes in drug efficacy and altered susceptibility to toxicity. Our study investigated the independent and combined …
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