Product stability and sequestration mechanisms in Solanum tuberosum engineered to biosynthesize high value ketocarotenoids
Mortimer, Cara L., Misawa, Norihiko, Ducreux, Laurence, Campbell, Raymond, Bramley, Peter M., Taylor, Mark, & Fraser, Paul D. (2016) Product stability and sequestration mechanisms in Solanum tuberosum engineered to biosynthesize high value ketocarotenoids. Plant Biotechnology Journal, 14(1), pp. 140-152.
To produce commercially valuable ketocarotenoids in Solanum tuberosum, the 4, 4′ β-oxygenase (crtW) and 3, 3′ β-hydroxylase (crtZ) genes from Brevundimonas spp. have been expressed in the plant host under constitutive transcriptional control. The CRTW and CRTZ enzymes are capable of modifying endogenous plant carotenoids to form a range of hydroxylated and ketolated derivatives. The host (cv. Désirée) produced significant levels of nonendogenous carotenoid products in all tissues, but at the apparent expense of the economically critical metabolite, starch. Carotenoid levels increased in both wild-type and transgenic tubers following cold storage; however, stability during heat processing varied between compounds. Subcellular fractionation of leaf tissues revealed the presence of ketocarotenoids in thylakoid membranes, but not predominantly in the photosynthetic complexes. A dramatic increase in the carotenoid content of plastoglobuli was determined. These findings were corroborated by microscopic analysis of chloroplasts. In tuber tissues, esterified carotenoids, representing 13% of the total pigment found in wild-type extracts, were sequestered in plastoglobuli. In the transgenic tubers, this proportion increased to 45%, with esterified nonendogenous carotenoids in place of endogenous compounds. Conversely, nonesterified carotenoids in both wild-type and transgenic tuber tissues were associated with amyloplast membranes and starch granules.
Impact and interest:
Citation counts are sourced monthly from and citation databases.
These databases contain citations from different subsets of available publications and different time periods and thus the citation count from each is usually different. Some works are not in either database and no count is displayed. Scopus includes citations from articles published in 1996 onwards, and Web of Science® generally from 1980 onwards.
Citations counts from theindexing service can be viewed at the linked Google Scholar™ search.
Full-text downloads displays the total number of times this work’s files (e.g., a PDF) have been downloaded from QUT ePrints as well as the number of downloads in the previous 365 days. The count includes downloads for all files if a work has more than one.
|Item Type:||Journal Article|
|Keywords:||Ketocarotenoid, carotenoid, Solanum tuberosum, Starch, Sequestration|
|Divisions:||Current > Research Centres > Centre for Tropical Crops and Biocommodities
Current > Schools > School of Earth, Environmental & Biological Sciences
Current > Institutes > Institute for Future Environments
Current > QUT Faculties and Divisions > Science & Engineering Faculty
|Copyright Owner:||Copyright 2015 Society for Experimental Biology, Association of Applied Biologists and John Wiley & Sons Ltd|
|Copyright Statement:||This is the accepted version of the following article: [full citation], which has been published in final form at http://onlinelibrary.wiley.com/doi/10.1111/pbi.12365/abstract|
|Deposited On:||14 Apr 2015 01:53|
|Last Modified:||18 May 2016 06:27|
Repository Staff Only: item control page