| Title |
ζ-Carotene cis isomers as products and substrates in the plant poly-cis carotenoid biosynthetic pathway to lycopene
|
|---|---|
| Published in |
Planta, October 2004
|
| DOI | 10.1007/s00425-004-1395-2 |
| Pubmed ID | |
| Authors |
Jürgen Breitenbach, Gerhard Sandmann |
| Abstract |
The plant carotenoid biosynthetic pathway to cyclic carotenes proceeds via carotene precursors in cis configuration. Involvement of individual isomers was elucidated by genetic complementation of desaturations and in vitro reactions of the corresponding enzyme. Determination of substrate and product specificity of phytoene and zeta-carotene desaturase revealed that 15-cis-phytoene is converted to 9,15,9'-tricis-zeta-carotene with 15,9'-dicis-phytofluene as intermediate by the first desaturase. Prior to a subsequent conversion by zeta-carotene desaturase, the 15-cis double bond of 9,15,9'-tricis-zeta-carotene has to be (photo)isomerized to all-trans. Then, the resulting 9,9'-dicis-zeta-carotene is utilized by zeta-carotene desaturase via 7,9,9'-tricis-neurosporene to 7,9,7',9'-tetracis-lycopene. Other zeta-carotene isomers that are assumed to be spontaneous isomerization products were not converted, except for the asymmetric 9-cis-zeta-carotene. This isomer is desaturated only to 7,9-dicis-neurosporene resembling a dead-end of the pathway. Prolycopene, the product of the desaturation reactions, is finally isomerized by a specific isomerase to all-trans-lycopene, which is a prerequisite for cyclization to beta-carotene. The 5-cis-lycopene and the 9-cis-and 13-cis-beta-carotene isomers detected in leaves are thought to originate independently from cis precursors by non-enzymatic isomerization of their all-trans forms. |
Mendeley readers
The data shown below were compiled from readership statistics for 84 Mendeley readers of this research output. Click here to see the associated Mendeley record.
Geographical breakdown
| Country | Count | As % |
|---|---|---|
| United States | 3 | 4% |
| Spain | 1 | 1% |
| New Zealand | 1 | 1% |
| Germany | 1 | 1% |
| Unknown | 78 | 93% |
Demographic breakdown
| Readers by professional status | Count | As % |
|---|---|---|
| Student > Ph. D. Student | 20 | 24% |
| Researcher | 15 | 18% |
| Student > Master | 14 | 17% |
| Student > Bachelor | 7 | 8% |
| Student > Postgraduate | 5 | 6% |
| Other | 14 | 17% |
| Unknown | 9 | 11% |
| Readers by discipline | Count | As % |
|---|---|---|
| Agricultural and Biological Sciences | 48 | 57% |
| Chemistry | 12 | 14% |
| Biochemistry, Genetics and Molecular Biology | 7 | 8% |
| Pharmacology, Toxicology and Pharmaceutical Science | 1 | 1% |
| Environmental Science | 1 | 1% |
| Other | 4 | 5% |
| Unknown | 11 | 13% |
Attention Score in Context
This research output has an Altmetric Attention Score of 3. This is our high-level measure of the quality and quantity of online attention that it has received. This Attention Score, as well as the ranking and number of research outputs shown below, was calculated when the research output was last mentioned on 16 January 2013.
All research outputs
#7,454,951
of 22,790,780 outputs
Outputs from Planta
#599
of 2,718 outputs
Outputs of similar age
#20,147
of 62,292 outputs
Outputs of similar age from Planta
#4
of 16 outputs
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So far Altmetric has tracked 2,718 research outputs from this source. They receive a mean Attention Score of 3.3. This one is in the 41st percentile – i.e., 41% of its peers scored the same or lower than it.
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