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https://www.readbyqxmd.com/read/29124283/semi-rational-engineering-of-cyp153a35-to-enhance-%C3%AF-hydroxylation-activity-toward-palmitic-acid
#1
Eunok Jung, Beom Gi Park, Hee-Wang Yoo, Joonwon Kim, Kwon-Young Choi, Byung-Gee Kim
CYP153A35 from Gordonia alkanivorans was recently characterized as fatty acid ω-hydroxylase. To enhance the catalytic activity of CYP153A35 toward palmitic acid, site-directed saturation mutagenesis was attempted using a semi-rational approach that combined structure-based computational analysis and subsequent saturation mutagenesis. Using colorimetric high-throughput screening (HTS) method based on O-demethylation activity of P450, CYP153A35 D131S and D131F mutants were selected. The best mutant, D131S, having a single mutation on BC-loop, showed 13- and 17-fold improvement in total turnover number (TTN) and catalytic efficiency (k cat/K M) toward palmitic acid compared to wild-type, respectively...
November 9, 2017: Applied Microbiology and Biotechnology
https://www.readbyqxmd.com/read/29115994/exploring-venlafaxine-pharmacokinetic-variability-with-a-phenotyping-approach-a-multicentric-french-swiss-study-marvel-study
#2
Célia Lloret-Linares, Youssef Daali, Sylvie Chevret, Isabelle Nieto, Fanny Molière, Philippe Courtet, Florence Galtier, Raphaëlle-Marie Richieri, Sophie Morange, Pierre-Michel Llorca, Wissam El-Hage, Thomas Desmidt, Frédéric Haesebaert, Philippe Vignaud, Jerôme Holtzmann, Jean-Luc Cracowski, Marion Leboyer, Antoine Yrondi, Fabienne Calvas, Liova Yon, Philippe Le Corvoisier, Olivier Doumy, Kyle Heron, Damien Montange, Siamak Davani, Julien Déglon, Marie Besson, Jules Desmeules, Emmanuel Haffen, Frank Bellivier
BACKGROUND: It is well known that the standard doses of a given drug may not have equivalent effects in all patients. To date, the management of depression remains mainly empirical and often poorly evaluated. The development of a personalized medicine in psychiatry may reduce treatment failure, intolerance or resistance, and hence the burden and costs of mood depressive disorders. The Geneva Cocktail Phenotypic approach presents several advantages including the "in vivo" measure of different cytochromes and transporter P-gp activities, their simultaneous determination in a single test, avoiding the influence of variability over time on phenotyping results, the administration of low dose substrates, a limited sampling strategy with an analytical method developed on DBS analysis...
November 7, 2017: BMC Pharmacology & Toxicology
https://www.readbyqxmd.com/read/29104318/comparison-of-the-oxidation-of-carcinogenic-aristolochic-acid-i-and-ii-by-microsomal-cytochromes-p450-in-vitro-experimental-and-theoretical-approaches
#3
Václav Martínek, František Bárta, Petr Hodek, Eva Frei, Heinz H Schmeiser, Volker M Arlt, Marie Stiborová
Abstract: The herbal drug aristolochic acid, a natural mixture of 8-methoxy-6-nitrophenanthro[3,4-d]-1,3-dioxole-5-carboxylic acid (AAI) and 6-nitrophenanthro[3,4-d]-1,3-dioxole-5-carboxylic acid (AAII), is derived from Aristolochia species and is the cause of two nephropathies. Ingestion of aristolochic acid is associated with the development of urothelial tumors linked with aristolochic acid nephropathy and is implicated in the development of Balkan endemic nephropathy-associated urothelial tumors...
2017: Monatshefte Für Chemie
https://www.readbyqxmd.com/read/29072349/functional-characterization-of-o-methyltransferases-used-to-catalyze-site-specific-methylation-in-the-post-tailoring-steps-of-pradimicin-biosynthesis
#4
J W Han, B G Ng, J K Sohng, Y J Yoon, G J Choi, B S Kim
AIMS: To identify the roles of the two O-methyltransferase homologous genes pdmF and pdmT in the pradimicin biosynthetic gene cluster of Actinomadura hibisca P157-2. METHODS AND RESULTS: Pradimicins are pentangular polyphenol antibiotics synthesized by bacterial type II polyketide synthases (PKSs) and tailoring enzymes. Pradimicins are naturally derivatized by combinatorial O-methylation at two positions (i.e., 7-OH and 11-OH) of the benzo[α]naphthacenequinone structure...
October 26, 2017: Journal of Applied Microbiology
https://www.readbyqxmd.com/read/29052962/bacterial-catabolism-of-lignin-derived-aromatics-new-findings-in-a-recent-decade
#5
Naofumi Kamimura, Kenji Takahashi, Kosuke Mori, Takuma Araki, Masaya Fujita, Yudai Higuchi, Eiji Masai
Lignin is the most abundant phenolic polymer; thus, its decomposition by microorganisms is fundamental to carbon cycling on earth. Lignin breakdown is initiated by depolymerization catalyzed by extracellular oxidoreductases secreted by white-rot basidiomycetous fungi. On the other hand, bacteria play a predominant role in the mineralization of lignin-derived heterogeneous low-molecular-weight aromatic compounds. The outline of bacterial catabolic pathways for lignin-derived bi- and monoaryls are typically composed of the following sequential steps: i) funneling of a wide variety of lignin-derived aromatics into vanillate and syringate, ii) O demethylation of vanillate and syringate to form catecholic derivatives, and iii) aromatic ring-cleavage of the catecholic derivatives to produce tricarboxylic acid cycle intermediates...
October 20, 2017: Environmental Microbiology Reports
https://www.readbyqxmd.com/read/29019074/in-vitro-inhibitory-effect-of-gymnema-sylvestre-extracts-and-total-gymnemic-acids-fraction-on-select-cytochrome-p450-activities-in-rat-liver-microsomes
#6
Madhuri Vaghela, Krishna Iyer, Nancy Pandita
BACKGROUND AND OBJECTIVES: Gymnema sylvestre R. Br. is a well-known Indian medicinal herb. Gymnemic acids are pentacyclic triterpenes saponins and active phytoconstituents of Gymnema sylvestre. The study aimed at evaluation of the in vitro rat liver cytochrome P450 (CYP) inhibition potential of extracts and total gymnemic acid (TA)-enriched fractions from G. sylvestre. METHODS: Standardization of G. sylvestre [ethanolic (EL), hydroethanolic (HE), total acid of ethanolic (TAE), total acid of hydroethanolic (TAHE) and total acid of aqueous (TAAQ) extract] was done with respect to deacyl gymnemic acid (DAGA), using reverse phase-high performance liquid chromatography (RP-HPLC)...
October 10, 2017: European Journal of Drug Metabolism and Pharmacokinetics
https://www.readbyqxmd.com/read/28994724/identification-of-metabolites-of-the-cardioprotective-alkaloid-dehydrocorydaline-in-rat-plasma-and-bile-by-liquid-chromatography-coupled-with-triple-quadrupole-linear-ion-trap-mass-spectrometry
#7
Huanyu Guan, Kaitong Li, Xiaoming Wang, Xiaomei Luo, Meifeng Su, Wenting Tan, Xiaoyan Chang, Yue Shi
Dehydrocorydaline (DHC), a quaternary alkaloid from Corydalis yanhusuo, has been demonstrated to be the active constituent in the treatment of coronary heart disease. In this study, a high-performance liquid chromatography-electrospray ionization-triple quadrupole linear ion trap mass spectrometry (HPLC-ESI-QTRAP MS) technique was used to identify DHC metabolites in plasma and bile after oral administration of DHC to rats. A total of 18 metabolites (M1 to M18) were identified and characterized by LC-MS/MS in the positive ion mode...
October 10, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/28951762/evaluation-of-antiulcer-and-cytotoxic-potential-of-the-leaf-flower-and-fruit-extracts-of-calotropis-procera-and-isolation-of-a-new-lignan-glycoside
#8
Areej Mohammad Al-Taweel, Shagufta Perveen, Ghada Ahmed Fawzy, Attiq Ur Rehman, Afsar Khan, Rashad Mehmood, Laila Mohamed Fadda
Calotropis procera is traditionally used for treating many diseases including ulcers and tumors. It was thus deemed of interest to investigate and compare the antiulcer and cytotoxic activities of C. procera leaf, flower, and fruit extracts in an attempt to verify its traditional uses. Phytochemical studies on the fruits, flowers, and leaves of C. procera, collected from the desert of Saudi Arabia, led to the isolation of one new lignan 7'-methoxy-3'-O-demethyl-tanegool-9-O-β-d-glucopyranoside and five known compounds from the flowers, four compounds from leaves, and a flavonoid glycoside and a lignan glycoside from the fruits...
2017: Evidence-based Complementary and Alternative Medicine: ECAM
https://www.readbyqxmd.com/read/28950382/comparison-of-in-vitro-hepatic-scoparone-7-o-demethylation-between-humans-and-experimental-animals
#9
Anam Fayyaz, Seddy Makwinja, Seppo Auriola, Hannu Raunio, Risto O Juvonen
Scoparone is a natural bioactive compound in Chinese herbal medicines. It has numerous pharmacological actions, including liver protective, hypolipidemic, antitumor, and anti-inflammatory effects. The primary metabolism route of scoparone is O-demethylation to scopoletin or isoscopoletin catalyzed by CYP enzymes. The aims of our study were to identify the human CYP enzymes catalyzing scoparone 7-O-demethylation to scopoletin and to compare this oxidation reaction in liver microsomes among different species...
September 26, 2017: Planta Medica
https://www.readbyqxmd.com/read/28934153/inhibitory-effect-of-selaginellins-from-selaginella-tamariscina-beauv-spring-against-cytochrome-p450-and-uridine-5-diphosphoglucuronosyltransferase-isoforms-on-human-liver-microsomes
#10
Jae-Kyung Heo, Phi-Hung Nguyen, Won Cheol Kim, Nguyen Minh Phuc, Kwang-Hyeon Liu
Selaginella tamariscina (Beauv.) has been used for traditional herbal medicine for treatment of cancer, hepatitis, and diabetes in the Orient. Numerous bioactive compounds including alkaloids, flavonoids, lignans, and selaginellins have been identified in this medicinal plant. Among them, selaginellins having a quinone methide unit and an alkylphenol moiety have been known to possess anticancer, antidiabetic, and neuroprotective activity. Although there have been studies on the biological activities of selaginellins, their modulatory potential of cytochrome P450 (P450) and uridine 5'-diphosphoglucuronosyltransferase (UGT) activities have not been previously evaluated...
September 21, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/28762065/lc-high-resolution-ms-ms-for-identification-of-69-metabolites-of-the-new-psychoactive-substance-1-4-ethylphenyl-n-2-methoxyphenyl-methyl-propane-2-amine-4-ea-nbome-in-rat-urine-and-human-liver-s9-incubates-and-comparison-of-its-screening-power-with-further
#11
Achim T Caspar, Folker Westphal, Markus R Meyer, Hans H Maurer
4-EA-NBOMe (N-(2-methoxybenzyl)-4-ethylamphetamine, 1-(4-ethylphenyl-)-N-[(2-methoxyphenyl)methyl]propane-2-amine) is an amphetamine-derived new psychoactive substance (NPS) of the N-methoxybenzyl (NBOMe) group first seized by German custom authorities. In contrast to the phenethylamine NBOMes, studies on the pharmacological, toxicological, or metabolic properties are not yet published. The aims of the presented work were the use of LC-HR-MS/MS for identification of the phase I and II metabolites of 4-EA-NBOMe in rat urine and pooled human S9 fraction (pS9) incubations, to compare metabolite formation in both models, to identify involved monooxygenases, and to elucidate its detectability in standard urine screening approaches (SUSAs) using GC-MS, LC-MS(n), and LC-HR-MS/MS...
July 31, 2017: Analytical and Bioanalytical Chemistry
https://www.readbyqxmd.com/read/28716728/cytochrome-p450-3a-selectively-affects-the-pharmacokinetic-interaction-between-erlotinib-and-docetaxel-in-rats
#12
Xuan Qin, Jian Lu, Peili Wang, Peipei Xu, Mingyao Liu, Xin Wang
Erlotinib as a first-line drug is used in non-small cell lung cancer (NSCLC) patients with sensitive EGFR mutations, while resistance to this drug will occur after several years of treatment. Therefore, the microtubule disturber docetaxel is introduced as combined regimen in clinical trials. This report investigated the potentials and mechanisms of drug-drug interaction (DDI) between erlotinib and docetaxel using wild type (WT) and Cyp3a1/2 knockout (KO) rats. The erlotinib O-demethylation and docetaxel hydroxylation reactions in the absence or the presence of another drug were analyzed in vitro via the assay of rat liver microsomes...
November 1, 2017: Biochemical Pharmacology
https://www.readbyqxmd.com/read/28669076/isolation-identification-optimization-and-metabolite-profiling-of-streptomyces-sparsus-vsm-30
#13
Ushakiranmayi Managamuri, Muvva Vijayalakshmi, V S Rama Krishna Ganduri, Satish Babu Rajulapati, Bodaiah Bonigala, B S Kalyani, Sudhakar Poda
Deep sea sediment samples of Bay of Bengal (Visakhapatnam) have been analyzed for actinomycetes as an elite source to screen for the production of bioactive metabolites. The actinomycetes strain VSM-30 has an exciting bioactivity profile and was isolated during our systemic screening of marine actinomycetes. It was identified as Streptomyces sparsus based on morphological, physiological, biochemical, and molecular approaches. Response surface methodology regression analysis was carried out to fit the experimental data of each response by the second-order polynomial...
July 2017: 3 Biotech
https://www.readbyqxmd.com/read/28665345/in-vitro-effect-of-8-prenylnaringenin-and-naringenin-on-fibroblasts-and-glioblastoma-cells-cellular-accumulation-and-cytotoxicity
#14
Monika Stompor, Łukasz Uram, Rafał Podgórski
Gliomas are one of the most aggressive and treatment-resistant types of human brain cancer. Identification and evaluation of anticancer properties of compounds found in plants, such as naringenin (N) and 8-prenylnaringenin (8PN), are among the most promising applications in glioma therapy. The prenyl group seems to be crucial to the anticancer activity of flavones, since it may lead to enhanced cell membrane targeting and thus increased intracellular activity. It should be noted that 8PN content in hop cones is 10 to 100 times lower compared to other flavonoids, such as xanthohumol...
June 30, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/28649680/enzymatic-competition-and-cooperation-branch-the-caerulomycin-biosynthetic-pathway-toward-different-2-2-bipyridine-members
#15
Ming Chen, Yipeng Zhang, Yanan Du, Qunfei Zhao, Qinglin Zhang, Jiequn Wu, Wen Liu
In this study, we characterized CaeB6 as a selective hydroxylase and CaeG1 as an O-methyltransferase in the biosynthesis of the 2,2'-bipyridine natural products caerulomycins (CAEs). The C3-hydroxylation activity of CaeB6 competes with the C4-O-methylation activity of CaeG1 and thereby branches the CAE pathway from a common C4-O-demethylated 2,2'-bipyridine intermediate. CaeG1-catalyzed C4-O-methylation leads to a main route that produces the major product CAE-A in Actinoalloteichus cyanogriseus NRRL B-2194...
July 5, 2017: Organic & Biomolecular Chemistry
https://www.readbyqxmd.com/read/28602505/proposal-of-5-methoxy-n-methyl-n-isopropyltryptamine-consumption-biomarkers-through-identification-of-in-vivo-metabolites-from-mice
#16
D Fabregat-Safont, M Barneo-Muñoz, F Martinez-Garcia, J V Sancho, F Hernández, M Ibáñez
New psychoactive substances (NPS) are a new breed of synthetically produced substances designed to mimic the effects of traditional illegal drugs. Synthetic cannabinoids and synthetic cathinones are the two most common groups, which try to mimic the effects of the natural compounds (9)Δ-tetrahydrocannabinol and cathinone, respectively. Similarly, synthetic tryptamines are designer compounds which are based on the compounds psilocin, N,N-dimethyltryptamine and 5-methoxy-N,N-dimethyltryptamine found in some mushrooms...
July 28, 2017: Journal of Chromatography. A
https://www.readbyqxmd.com/read/28495902/regio-and-stereo-selective-oxidation-of-a-cardiovascular-drug-metoprolol-mediated-by-cytochrome-p450-2d-and-3a-enzymes-in-marmoset-livers
#17
Shotaro Uehahara, Sakura Ishii, Yasuhiro Uno, Takashi Inoue, Erika Sasaki, Hiroshi Yamazaki
A β-blocker metoprolol is one of the in vivo probes for human cytochrome P450 (P450) 2D6. Investigation of non-human primate P450 enzymes helps improve accuracy of the extrapolation of pharmacokinetic data from animals into humans. Common marmosets (Callithrix jacchus) are a potential primate model for preclinical research, but detailed roles of marmoset P450 enzymes in metoprolol oxidations remained unknown. In this study, regio- and stereo-selectivity of metoprolol oxidations by a variety of P450 enzymes in marmoset and human livers were investigated in vitro...
May 11, 2017: Drug Metabolism and Disposition: the Biological Fate of Chemicals
https://www.readbyqxmd.com/read/28488816/characterization-of-methyltransferase-almcii-in-chalcomycin-biosynthesis-the-first-tylf-family-o-methyltransferase-works-on-a-4-deoxysugar
#18
Ping Dai, Chuan-Xi Wang, Hao Gao, Qiao-Zhen Wang, Xiao-Long Tang, Guo-Dong Chen, Kui Hong, Dan Hu, Xin-Sheng Yao
Sugar O-methylation is a ubiquitous modification in natural products and plays diverse roles. This realization has inspired many attempts to search for novel methyltransferases. Chalcomycins are a group of 16-membered macrolides containing two methylated sugars that require three methyltransferases for their biosynthesis. Here, we identified that AlmCII, a sugar O-methyltransferase belonging to the TylF family that was previously only known to methylate sugars with a 4'-hydroxy group, can methylate a 4',6'-dideoxysugar during the biosynthesis of chalcomycins...
May 10, 2017: Chembiochem: a European Journal of Chemical Biology
https://www.readbyqxmd.com/read/28472358/metabolic-profile-determination-of-nbome-compounds-using-human-liver-microsomes-and-comparison-with-findings-in-authentic-human-blood-and-urine
#19
Keith-Dane H Temporal, Karen S Scott, Amanda L A Mohr, Barry K Logan
The emergence of novel psychoactive substances (NPS) such as hallucinogenic NBOMes (N-methoxybenzyl derivatives of 2C phenethylamines) in the past few years into the recreational drug market has introduced various challenges in forensic analytical toxicology in regard to adequate and timely detection of these compounds. This is especially true in samples from individuals who have experienced severe and fatal intoxications. The aim of this research was to identify the major Phase I metabolites of selected NBOMe compounds to generate a predicted human metabolic pathway of these substances...
September 1, 2017: Journal of Analytical Toxicology
https://www.readbyqxmd.com/read/28455804/microbial-catalyzed-regio-selective-demethylation-of-colchicine-by-streptomyces-griseus-atcc-13273
#20
Chao Zhang, Xian Sun, Shao Hua Xu, Bo Yang Yu, Jian Zhang
Colchicinoids and their derivatives are of great importance in pharmaceutical applications, and colchicine is usually used as the first choice for the treatment of gout. To expand the structural diversities and clinical application of colchicinoids, many attempts have been established for the derivatives with better activity or less toxicity. Herein, in this paper, we report a direct microbial transformation of colchicine into 2-O-demethyl-colchicine (M1) and 3-O-demethl-colchicine (M2) by Streptomyces griseus ATCC 13273...
April 28, 2017: Applied Biochemistry and Biotechnology
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