Astaxanthin

Isolation and functional characterisation of a novel type of carotenoid biosynthetic gene from Xanthophyllomyces dendrorhous.

Verdoes JC, Krubasik KP, Sandmann G, van Ooyen AJ.

Department of Food Technology and Nutritional Sciences, Wageningen University, The Netherlands. Jan.Verdoes@imb.ftns.wau.nl

The red heterobasidiomycetous yeast Xanthophyllomyces dendrorhous (perfect state of Phaffia rhodozyma) contains a novel type of carotenoid biosynthetic enzyme. Its structural gene, designated crtYB, was isolated by functional complementation in a genetically modified, carotenogenic Escherichia coli strain. Expression studies in different carotenogenic E. coli strains demonstrated that the crt YB gene encodes a bifunctional protein involved both in synthesis of phytoene from geranylgeranyl diphosphate and in cyclisation of lycopene to beta-carotene. By sequence comparison with other phytoene synthases and complementation studies in E. coli with various deletion derivatives of the crtYB gene, the regions responsible for phytoene synthesis and lycopene cyclisation were localised within the protein.

PMID: 10589832 [PubMed - indexed for MEDLINE]