First published online November 19, 2004; 10.1104/pp.104.052092
Plant Physiology 136:4246-4255 (2004)
© 2004 American Society of Plant Biologists
BIOCHEMICAL PROCESSES AND MACROMOLECULAR STRUCTURES
Analysis in Vitro of the Enzyme CRTISO Establishes a Poly-cis-Carotenoid Biosynthesis Pathway in Plants1
Tal Isaacson,
Itzhak Ohad,
Peter Beyer and
Joseph Hirschberg*
Departments of Genetics (T.I., J.H.) and Biological Chemistry (I.O.), The Hebrew University of Jerusalem, Jerusalem 91904, Israel; and Center for Applied Biosciences, Universität Freiburg, 79104 Freiburg, Germany (P.B.)
Most enzymes in the central pathway of carotenoid biosynthesis in plants have been identified and studied at the molecular level. However, the specificity and role of cis-trans-isomerization of carotenoids, which occurs in vivo during carotene biosynthesis, remained unresolved. We have previously cloned from tomato (Solanum lycopersicum) the CrtISO gene, which encodes a carotene cis-trans-isomerase. To study the biochemical properties of the enzyme, we developed an enzymatic in vitro assay in which a purified tomato CRTISO polypeptide overexpressed in Escherichia coli cells is active in the presence of an E. coli lysate that includes membranes. We show that CRTISO is an authentic carotene isomerase. Its catalytic activity of cis-to-trans isomerization requires redox-active components, suggesting that isomerization is achieved by a reversible redox reaction acting at specific double bonds. Our data demonstrate that CRTISO isomerizes adjacent cis-double bonds at C7 and C9 pairwise into the trans-configuration, but is incapable of isomerizing single cis-double bonds at C9 and C9'. We conclude that CRTISO functions in the carotenoid biosynthesis pathway in parallel with -carotene desaturation, by converting 7,9,9'-tri-cis-neurosporene to 9'-cis-neurosporene and 7'9'-di-cis-lycopene into all-trans-lycopene. These results establish that in plants carotene desaturation to lycopene proceeds via cis-carotene intermediates.
1 This work was supported by The Israel Science Foundation and by the European Commission (contract "ProVitA"; QLK3CT20000809). Work in the laboratories of J.H. and I.O. is carried out under the auspices of the Avron Even-Ari Minerva Center.
Article, publication date, and citation information can be found at www.plantphysiol.org/cgi/doi/10.1104/pp.104.052092.
* Corresponding author; e-mail hirschu{at}vms.huji.ac.il; fax (972)25633066.
Received August 19, 2004;
returned for revision October 16, 2004;
accepted October 17, 2004.
This article has been cited by other articles:

|
 |

|
 |
 
C. I. Cazzonelli, A. C. Roberts, M. E. Carmody, and B. J. Pogson
Transcriptional Control of SET DOMAIN GROUP 8 and CAROTENOID ISOMERASE during Arabidopsis Development
Mol Plant,
November 17, 2009;
(2009)
ssp092v1.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
C. I. Cazzonelli, A. J. Cuttriss, S. B. Cossetto, W. Pye, P. Crisp, J. Whelan, E. J. Finnegan, C. Turnbull, and B. J. Pogson
Regulation of Carotenoid Composition and Shoot Branching in Arabidopsis by a Chromatin Modifying Histone Methyltransferase, SDG8
PLANT CELL,
January 1, 2009;
21(1):
39 - 53.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
R. Welsch, F. Wust, C. Bar, S. Al-Babili, and P. Beyer
A Third Phytoene Synthase Is Devoted to Abiotic Stress-Induced Abscisic Acid Formation in Rice and Defines Functional Diversification of Phytoene Synthase Genes
Plant Physiology,
May 1, 2008;
147(1):
367 - 380.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
P. D. Fraser, E. M.A. Enfissi, J. M. Halket, M. R. Truesdale, D. Yu, C. Gerrish, and P. M. Bramley
Manipulation of Phytoene Levels in Tomato Fruit: Effects on Isoprenoids, Plastids, and Intermediary Metabolism
PLANT CELL,
October 1, 2007;
19(10):
3194 - 3211.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
F. Li, C. Murillo, and E. T. Wurtzel
Maize Y9 Encodes a Product Essential for 15-cis-{zeta}-Carotene Isomerization
Plant Physiology,
June 1, 2007;
144(2):
1181 - 1189.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
F. X. Cunningham Jr., H. Lee, and E. Gantt
Carotenoid Biosynthesis in the Primitive Red Alga Cyanidioschyzon merolae
Eukaryot. Cell,
March 1, 2007;
6(3):
533 - 545.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
S. Al-Babili, T. T. C. Hoa, and P. Schaub
Exploring the potential of the bacterial carotene desaturase CrtI to increase the {beta}-carotene content in Golden Rice
J. Exp. Bot.,
March 1, 2006;
57(4):
1007 - 1014.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
I. Neta-Sharir, T. Isaacson, S. Lurie, and D. Weiss
Dual Role for Tomato Heat Shock Protein 21: Protecting Photosystem II from Oxidative Stress and Promoting Color Changes during Fruit Maturation
PLANT CELL,
June 1, 2005;
17(6):
1829 - 1838.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
P. Schaub, S. Al-Babili, R. Drake, and P. Beyer
Why Is Golden Rice Golden (Yellow) Instead of Red?
Plant Physiology,
May 1, 2005;
138(1):
441 - 450.
[Abstract]
[Full Text]
[PDF]
|
 |
|
|
|