Send to

Choose Destination
See comment in PubMed Commons below
Biotechnol Bioeng. 2009 Aug 1;103(5):944-55. doi: 10.1002/bit.22330.

Characterization of cyanobacterial beta-carotene ketolase and hydroxylase genes in Escherichia coli, and their application for astaxanthin biosynthesis.

Author information

  • 1Biological and Environmental Systems Group, ChELSI, Department of Chemical and Process Engineering, University of Sheffield, Mappin Street, Sheffield S13JD, United Kingdom.


Carotenoid biosynthesis is highly conserved and well characterized up to the synthesis of beta-carotene. Conversely, the synthesis of astaxanthin from beta-carotene is less well characterized. Regardless, astaxanthin is a highly sought natural product, due to its various industrial applications and elevated antioxidant capacity. In this article, 12 beta-carotene ketolase and 4 beta-carotene hydroxylase genes, isolated from 5 cyanobacterial species, are investigated for their function, and potential for microbial astaxanthin synthesis. Further, this in vivo comparison identifies and applies the most promising genetic elements within a dual expression vector, which is maintained in Escherichia coli. Here, combined overexpression of individual beta-carotene ketolase and beta-carotene hydroxylase genes, within a beta-carotene accumulating host, enables a 23.5-fold improvement in total carotenoid yield (1.99 mg g(-1)), over the parental strain, with >90% astaxanthin.

[PubMed - indexed for MEDLINE]
PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Wiley
    Loading ...
    Support Center