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Title: Isotopically nonstationary 13 C flux analysis of cyanobacterial isobutyraldehyde production

Authors:
; ; ; ; ;
Publication Date:
Sponsoring Org.:
USDOE
OSTI Identifier:
1397026
Grant/Contract Number:
SC0008118; AC05-06OR23100; P200A090323
Resource Type:
Journal Article: Publisher's Accepted Manuscript
Journal Name:
Metabolic Engineering
Additional Journal Information:
Journal Volume: 42; Journal Issue: C; Related Information: CHORUS Timestamp: 2017-10-04 16:29:35; Journal ID: ISSN 1096-7176
Publisher:
Elsevier
Country of Publication:
Belgium
Language:
English

Citation Formats

Jazmin, Lara J., Xu, Yao, Cheah, Yi Ern, Adebiyi, Adeola O., Johnson, Carl Hirschie, and Young, Jamey D.. Isotopically nonstationary 13 C flux analysis of cyanobacterial isobutyraldehyde production. Belgium: N. p., 2017. Web. doi:10.1016/j.ymben.2017.05.001.
Jazmin, Lara J., Xu, Yao, Cheah, Yi Ern, Adebiyi, Adeola O., Johnson, Carl Hirschie, & Young, Jamey D.. Isotopically nonstationary 13 C flux analysis of cyanobacterial isobutyraldehyde production. Belgium. doi:10.1016/j.ymben.2017.05.001.
Jazmin, Lara J., Xu, Yao, Cheah, Yi Ern, Adebiyi, Adeola O., Johnson, Carl Hirschie, and Young, Jamey D.. 2017. "Isotopically nonstationary 13 C flux analysis of cyanobacterial isobutyraldehyde production". Belgium. doi:10.1016/j.ymben.2017.05.001.
@article{osti_1397026,
title = {Isotopically nonstationary 13 C flux analysis of cyanobacterial isobutyraldehyde production},
author = {Jazmin, Lara J. and Xu, Yao and Cheah, Yi Ern and Adebiyi, Adeola O. and Johnson, Carl Hirschie and Young, Jamey D.},
abstractNote = {},
doi = {10.1016/j.ymben.2017.05.001},
journal = {Metabolic Engineering},
number = C,
volume = 42,
place = {Belgium},
year = 2017,
month = 7
}

Journal Article:
Free Publicly Available Full Text
This content will become publicly available on May 13, 2018
Publisher's Accepted Manuscript

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  • Improving plant productivity is an important aim for metabolic engineering. There are few comprehensive methods that quantitatively describe leaf metabolism, although such information would be valuable for increasing photosynthetic capacity, enhancing biomass production, and rerouting carbon flux toward desirable end products. Isotopically nonstationary metabolic flux analysis (INST-MFA) has been previously applied to map carbon fluxes in photoautotrophic bacteria, which involves model-based regression of transient 13C-labeling patterns of intracellular metabolites. However, experimental and computational difficulties have hindered its application to terrestrial plant systems. Here, we performed in vivo isotopic labeling of Arabidopsis thaliana rosettes with 13CO 2 and estimated fluxes throughoutmore » leaf photosynthetic metabolism by INST-MFA. Plants grown at 200 µmol m $-$2s $-$1 light were compared with plants acclimated for 9 d at an irradiance of 500 µmol∙m $-$2∙s $-$1. Approximately 1,400 independent mass isotopomer measurements obtained from analysis of 37 metabolite fragment ions were regressed to estimate 136 total fluxes (54 free fluxes) under each condition. The results provide a comprehensive description of changes in carbon partitioning and overall photosynthetic flux after long-term developmental acclimation of leaves to high light. Despite a doubling in the carboxylation rate, the photorespiratory flux increased from 17 to 28% of net CO 2 assimilation with high-light acclimation (Vc/Vo: 3.5:1 vs. 2.3:1, respectively). In conclusion, this study highlights the potential of 13C INST-MFA to describe emergent flux phenotypes that respond to environmental conditions or plant physiology and cannot be obtained by other complementary approaches.« less
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  • Gamma-linolenic acid (GLA), a nutritionally important fatty acid in human and animal diets, is not produced in oil seed crops. Many oil seed plants, however, produce significant quantities of linoleic acid, a fatty acid that could be converted to GLA by the enzyme {del}{sup 6}-desaturase if it were present. As a first step to producing GLA in oil seed crops, we have cloned a cyanobacterial {del}{sup 6}-desaturase gene. Expression of this gene in transgenic tobacco resulted in GLA accumulation. Octadecatetraenoic acid, a highly unsaturated, industrially important fatty acid, was also found in transgenic tobacco plants expressing the cyanobacterial {del}{sup 6}-desaturase.more » This is the first example of engineering the production of `novel` polyunsaturated fatty acids in transgenic plants. 28 refs., 4 figs., 1 tab.« less