Stereochemistry of the Enzymatic Cyclisation of 4,2',4'-Trihydroxychalcone to 7,4'-Dihydroxyflavanone by Isomerases from Mung Bean Seedlings
Year: 1970
Type: article
Abstract: The stereochemistry of the enzyme mediated chalcone-flavanone isomerisation has been investigated. Cyclisation of 4,2′,4′-trihydroxychalcone catalysed by either one of the two chalconeflavanone isomerases isolated from mung bean seedlings (Phaseolus aureus Roxb.) leads to the (–)(2 S)-7,4′-dihydroxyflavanone. When 4,2′,4′-[α-2H]trihydroxychalcone is the substrate, deuterium is located preferentially in the equatorial position at C-3 of the flavanone as was shown by nuclear magnetic resonance measurements. Conversely, when the cyclisation is carried out in 2H2O with the unlabeled chalcone, deuterium is preferentially located in the axial position at C-3 of the flavanone. The mechanistic implications of these results are discussed.
Source: European Journal of Biochemistry
Authors: Klaus Hahlbrock, Harald Zilg, Hans Grisebach
Institutions: University of Freiburg, University of California, Davis
Language: English
Subfield: Molecular Biology
Domain: Life Sciences
Open Access status: bronze
OpenAlex ID: W1991990692