446-71-9Relevant articles and documents
Discovery of Novel Bacterial Chalcone Isomerases by a Sequence-Structure-Function-Evolution Strategy for Enzymatic Synthesis of (S)-Flavanones
Bornscheuer, Uwe T.,Brückner, Stephan I.,Gei?ler, Torsten,Gross, Egon,Hartmann, Beate,Ley, Jakob P.,Meinert, Hannes,R?ttger, Carsten,Schuiten, Eva,Yi, Dong,Zirpel, Bastian
supporting information, p. 16874 - 16879 (2021/07/06)
Chalcone isomerase (CHI) is a key enzyme in the biosynthesis of flavonoids in plants. The first bacterial CHI (CHIera) was identified from Eubacterium ramulus, but its distribution, evolutionary source, substrate scope, and stereoselectivity are still unclear. Here, we describe the identification of 66 novel bacterial CHIs from Genbank using a novel Sequence-Structure-Function-Evolution (SSFE) strategy. These novel bacterial CHIs show diversity in substrate specificity towards various hydroxylated and methoxylated chalcones. The mutagenesis of CHIera according to the substrate binding models of these novel bacterial CHIs resulted in several variants with greatly improved activity towards these chalcones. Furthermore, the preparative scale conversion catalyzed by bacterial CHIs has been performed for five chalcones and revealed (S)-selectivity with up to 96 % ee, which provides an alternative biocatalytic route for the synthesis of (S)-flavanones in high yields.
Biological Properties and Absolute Configuration of Flavanones From Calceolaria thyrsiflora Graham
Cabezas, Francisco,Cortez-San Martín, Marcelo,Díaz, Katy,González, César,Joseph-Nathan, Pedro,Mascayano, Carolina,Mejias, Sophia,Montoya, Margarita,Mu?oz, Marcelo A.,Osorio, Mauricio,Taborga, Lautaro,Torrent, Claudia,Vásquez-Martínez, Yesseny,Valdés, Ernesto
, (2020/08/19)
Flavanones (–)-(2S)-5,4’-dihydroxy-7-methoxyflavanone (1) and (–)-(2S)-5,3’,4’-trihydroxy-7-methoxyflavanone (2) were isolated from the extracts of Calceolaria thyrsiflora Graham, an endemic perennial small shrub growing in the central zone of Chile. The absolute configuration of these compounds was resolved by optical rotation experiments and in silico calculations. Three analogs (3, 4, and 5) were synthesized to do structure-activity relationships with the biological assays studied. Biological tests revealed that only flavanone 2 exhibited a moderate inhibitory activity against the methicillin-resistant strain S. aureus MRSA 97-77 (MIC value of 50 μg/ml). In addition, flavanone 2 showed a potent, selective, and competitive inhibition of 5-hLOX, which supports the traditional use of this plant as an anti-inflammatory in diseases of the respiratory tract. Also, 2 exhibited cytotoxic and selective effects against B16-F10 (8.07 ± 1.61 μM) but 4.6- and 17-fold lesser activity than etoposide and taxol.
Influence of Substrate Binding Residues on the Substrate Scope and Regioselectivity of a Plant O-Methyltransferase against Flavonoids
Tang, Qingyun,Vianney, Yoanes M.,Weisz, Klaus,Grathwol, Christoph W.,Link, Andreas,Bornscheuer, Uwe T.,Pavlidis, Ioannis V.
, p. 3721 - 3727 (2020/06/02)
Methylation of free hydroxyl groups is an important modification for flavonoids. It not only greatly increases absorption and oral bioavailability of flavonoids, but also brings new biological activities. Flavonoid methylation is usually achieved by a specific group of plant O-methyltransferases (OMTs) which typically exhibit high substrate specificity. Here we investigated the effect of several residues in the binding pocket of the Clarkia breweri isoeugenol OMT on the substrate scope and regioselectivity against flavonoids. The mutation T133M, identified as reported in our previous publication, increased the activity of the enzyme against several flavonoids, namely eriodictyol, naringenin, luteolin, quercetin and even the isoflavonoid genistein, while a reduced set of amino acids at positions 322 and 326 affected both, the activity and the regioselectivity of the methyltranferase. On the basis of this work, methylated flavonoids that are rare in nature were produced in high purity.
