76824-99-2Relevant articles and documents
Oxidative cyclization of N-methyl-dopa by a fungal flavoenzyme of the amine oxidase family
Lahham, Majd,Pavkov-Keller, Tea,Fuchs, Michael,Niederhauser, Johannes,Chalhoub, Gabriel,Daniel, Bastian,Kroutil, Wolfgang,Gruber, Karl,Macheroux, Peter
, p. 17021 - 17032 (2018/11/21)
Flavin-dependent enzymes catalyze many oxidations, including formation of ring structures in natural products. The gene cluster for biosynthesis of fumisoquins, secondary metabolites structurally related to isoquinolines, in the filamentous fungus Aspergillus fumigatus harbors a gene that encodes a flavoprotein of the amine oxidase family, termed fsqB (fumisoquin biosynthesis gene B). This enzyme catalyzes an oxidative ring closure reaction that leads to the formation of isoquinoline products. This reaction is reminiscent of the oxidative cyclization reported for berberine bridge enzyme and tetrahydrocannabinol synthase. Despite these similarities, amine oxidases and berberine bridge enzyme–like enzymes possess distinct structural properties, prompting us to investigate the structure–function relationships of FsqB. Here, we report the recombinant production and purification of FsqB, elucidation of its crystal structure, and kinetic analysis employing five putative substrates. The crystal structure at 2.6 ? resolution revealed that FsqB is a member of the amine oxidase family with a covalently bound FAD cofactor. N-methyl-dopa was the best substrate for FsqB and was completely converted to the cyclic isoquinoline product. The absence of the meta-hydroxyl group, as e.g. in L-Nmethyl-tyrosine, resulted in a 25-fold lower rate of reduction and the formation of the demethylated product L-tyrosine, instead of a cyclic product. Surprisingly, FsqB did not accept the D-stereoisomer of N-methyltyrosine, in contrast to N-methyl-dopa, for which both stereoisomers were oxidized with similar rates. On the basis of the crystal structure and docking calculations, we postulate a substrate-dependent population of distinct binding modes that rationalizes stereospecific oxidation in the FsqB active site.
MODULATORS OF REV-ERB
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Page/Page column 117; 118; 119, (2015/07/16)
The subject matter herein concerns the identification and development of potent synthetic REV-ERB ligands, such as in vivo agonists and antagonists. These compounds allow for characterization of the effects of modulation of this receptor in vivo specifically on circadian behavior and metabolism, and have suitable characteristics for development of medicinal compounds useful for treatment of malconditions such as diabetes, obesity, atherosclerosis, dyslipidemia, a circadian rhythm disorder, coronary artery disease, bipolar disorder, depression, cancer, a sleep disorder, an anxiety disorder, an addiction disorder, a bone-related disorder such osteoporosis, a skeletal muscle disease, e.g., with compromised exercise capacity, or an autoimmune disorder such as psoriasis, multiple sclerosis, inflammatory bowel disease, and others.
6-Hydroxy-1,2,3,4-tetrahydro-isoquinoline-3-carboxylic acid mimics active conformation of tyrosine in opioid peptides
Sperlinga, Emanuela,Kosson, Piotr,Urbanczyk-Lipkowska, Zofia,Ronsisvalle, Giuseppe,Carr, Daniel B.,Lipkowski, Andrzej W.
, p. 2467 - 2469 (2007/10/03)
6-Hydroxy-1,2,3,4-tetrahydro-isoquinoline-3-carboxylic acid (6Htc) has been proposed as a rigid mimic of tyrosine conformation in opioid ligand-receptor complex. The significant receptor binding to mu and delta opioid receptors of respective analogues of
