A novel oxygenase from Pleurotus sapidus transforms valencene to nootkatone

Molecular Characterization of a Lipoxygenase from the Basidiomycete MushroomPleurotus ostreatus

“…Valencene dioxygenase catalyzes selective allylic oxidation of the sesquiterpene (þ)-valencene to the grapefruit flavor (þ)-nootkatone via intermediate hydroperoxides. 33) Thus, because the catalytic mechanism of valencene dioxygenase is similar to that of known LOXs, this enzyme is suggested to be a LOX-type enzyme. A remarkable feature of this enzyme is that it accepts a terpene hydrocarbon instead of PUFAs as substrate.…”

“…Comparative analysis of the PoLOX1 amino acid sequence A BLAST search of sequence databases done using the deduced amino acid sequence of PoLOX1 revealed that PoLOX1 shared highest identity with a valencene dioxygenase of Pleurotus sapidus (PsaOx1, 77% identity), 33) $50% identity with putative LOX-like proteins from ascomycete, basidiomycete, and deuteromycete fungi, and $29% identity with known LOXs from animals, plants, and bacteria. The regions in the middle and C-terminal portions of the proteins showed substantial sequence similarity, whereas their N-terminal portions were divergent.…”

Crosses between monokaryons of Pleurotus sapidus or Pleurotus florida show an improved biotransformation of (+)-valencene to (+)-nootkatone

“…After 6 days of growth, the culture was harvested, separated from the supernatant by centrifugation, and the fungal mycelium was washed twice with distilled water. The obtained biomass was lyophilised, using a VaCo 2 (Zirbus Technology, Bad Grund, Germany), and stored at À20°C until usage (Fraatz et al, 2009b).…”

“…These processes outclass traditional chemistry, as they proceed under mild conditions, show better regio-and enantioselectivity, do not generate toxic wastes and result in products labeled 'natural' (Berger, 2009). In particular, the oxidation of (+)-valencene using Pleurotus sapidus is attractive to obtain the high added-value compound (+)-nootkatone, an impact flavour of grapefruit with an odor threshold of $1 lg L À1 water (Fraatz et al, 2009b;Krügener et al, 2010). Recently, the enzyme responsible this transformation was identified as the first http://dx.doi.org/10.1016/j.biortech.2014.08.061 0960-8524/Ó 2014 Elsevier Ltd. All rights reserved.…”

Bedeutung der Biotechnologie in der Lebensmittelproduktion

“…Dieses kann mithilfe von Submerskulturen des Speisepilzes Pleurotus sapidus allylisch zum Grapefruitaroma Nootkaton oxidiert werden (Abb. 1, [8]). ó…”