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Title: Modulation of saturation and chain length of fatty acids in Saccharomyces cerevisiae for production of cocoa butter-like lipids

Authors:
ORCiD logo [1]; ORCiD logo [1]; ORCiD logo [1]; ORCiD logo [1]; ORCiD logo [2]
  1. Department of Biology and Biological Engineering, Chalmers University of Technology, Gothenburg Sweden, Novo Nordisk Foundation Center for Biosustainability, Chalmers University of Technology, Gothenburg Sweden
  2. Department of Biology and Biological Engineering, Chalmers University of Technology, Gothenburg Sweden, Novo Nordisk Foundation Center for Biosustainability, Chalmers University of Technology, Gothenburg Sweden, Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Lyngby Denmark
Publication Date:
Sponsoring Org.:
USDOE
OSTI Identifier:
1417946
Grant/Contract Number:
SC0008744
Resource Type:
Journal Article: Publisher's Accepted Manuscript
Journal Name:
Biotechnology and Bioengineering
Additional Journal Information:
Related Information: CHORUS Timestamp: 2018-01-24 15:07:21; Journal ID: ISSN 0006-3592
Publisher:
Wiley Blackwell (John Wiley & Sons)
Country of Publication:
United States
Language:
English

Citation Formats

Bergenholm, David, Gossing, Michael, Wei, Yongjun, Siewers, Verena, and Nielsen, Jens. Modulation of saturation and chain length of fatty acids in Saccharomyces cerevisiae for production of cocoa butter-like lipids. United States: N. p., 2018. Web. doi:10.1002/bit.26518.
Bergenholm, David, Gossing, Michael, Wei, Yongjun, Siewers, Verena, & Nielsen, Jens. Modulation of saturation and chain length of fatty acids in Saccharomyces cerevisiae for production of cocoa butter-like lipids. United States. doi:10.1002/bit.26518.
Bergenholm, David, Gossing, Michael, Wei, Yongjun, Siewers, Verena, and Nielsen, Jens. 2018. "Modulation of saturation and chain length of fatty acids in Saccharomyces cerevisiae for production of cocoa butter-like lipids". United States. doi:10.1002/bit.26518.
@article{osti_1417946,
title = {Modulation of saturation and chain length of fatty acids in Saccharomyces cerevisiae for production of cocoa butter-like lipids},
author = {Bergenholm, David and Gossing, Michael and Wei, Yongjun and Siewers, Verena and Nielsen, Jens},
abstractNote = {},
doi = {10.1002/bit.26518},
journal = {Biotechnology and Bioengineering},
number = ,
volume = ,
place = {United States},
year = 2018,
month = 1
}

Journal Article:
Free Publicly Available Full Text
This content will become publicly available on January 24, 2019
Publisher's Accepted Manuscript

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  • Enzyme and metabolic engineering offer the potential to develop biocatalysts for converting natural resources to a wide range of chemicals. To broaden the scope of potential products beyond natural metabolites, methods of engineering enzymes to accept alternative substrates and/or perform novel chemistries must be developed. DNA synthesis can create large libraries of enzyme-coding sequences, but most biochemistries lack a simple assay to screen for promising enzyme variants. Our solution to this challenge is structure-guided mutagenesis, in which optimization algorithms select the best sequences from libraries based on specified criteria (i.e., binding selectivity). We demonstrate this approach by identifying medium-chain (C8–C12)more » acyl-ACP thioesterases through structure-guided mutagenesis. Medium-chain fatty acids, which are products of thioesterase-catalyzed hydrolysis, are limited in natural abundance, compared to long-chain fatty acids; the limited supply leads to high costs of C6–C10 oleochemicals such as fatty alcohols, amines, and esters. Here, we applied computational tools to tune substrate binding of the highly active ‘TesA thioesterase in Escherichia coli. We used the IPRO algorithm to design thioesterase variants with enhanced C12 or C8 specificity, while maintaining high activity. After four rounds of structure-guided mutagenesis, we identified 3 variants with enhanced production of dodecanoic acid (C12) and 27 variants with enhanced production of octanoic acid (C8). The top variants reached up to 49% C12 and 50% C8 while exceeding native levels of total free fatty acids. A comparably sized library created by random mutagenesis failed to identify promising mutants. The chain length-preference of ‘TesA and the best mutant were confirmed in vitro using acyl-CoA substrates. Molecular dynamics simulations, confirmed by resolved crystal structures, of ‘TesA variants suggest that hydrophobic forces govern ‘TesA substrate specificity. Finally, we expect the design rules that we uncovered and the thioesterase variants that we identified will be useful to metabolic engineering projects aimed at sustainable production of medium-chain-length oleochemicals.« less
  • ABS>G-yields of hydrocarbons resulting from /sup 60/Co gamma - irradiation of normal saturated C/sub 12/, C/sub 14/, C/sub 16/, C/sub 18/, C/sub 20/, and C /sub 30/ fatty (carboxylic) acids in the crystalline state (and of the C/sub 16/ and C/sub 18/ acids in the liquid state) have been determined. G/sub RH/ values obtained are in substantial agreement with G/sub CO//sub 2/ values recently reported for the same substances (excepting the C/sub 30/ homolog) by Jones and his observation that G/sub CO//sub 2/ (and hence G/sub RH/) is, in general, inversely related to chain length is confirmed. Contrary to earliermore » claim melissic acid (triacontanoic acid, the C/sub 30/ homolog) behaves normally in this regard. Departures from the inverse chain-length relationship are compatible with and may be rationalized by consideration of an additional inverse effect of the density of the irradiated material. (auth)« less
  • Terminally iodinated long-chain fatty acids have been used experimentally and clinically as myocardial imaging agents. Six omega-iodo fatty acids (I(CH2)n CO2H, where n . 10, 12, 15, 18, 21, 26) have been synthesized and tested in rats. Myocardial extraction values and heart-to-blood ratios are affected by chain length. Extraction is shown to be highest for n . 18 and 21, as are heart-to-blood ratios at 5 min. The cellular fate of the fatty acid changes form that of beta -oxidation for n less than or equal to 15 to predominantly triglyceride storage for n . 18 and 21, as shownmore » by analysis of rat heart homogenates by thin layer chromatography at two time intervals.« less
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