studies on physiology, transcriptomics and interactions with industrial microbial isolates
Tiukova, Ievgeniia
(2014).
Dekkera bruxellensis, a non-conventional ethanol production yeast.
Diss. (sammanfattning/summary)
Uppsala :
Sveriges lantbruksuniv.,
Acta Universitatis Agriculturae Sueciae, 1652-6880
; 2014:40
ISBN 978-91-576-8028-0
eISBN 978-91-576-8029-7
[Doctoral thesis]
![]() |
PDF
363kB |
Abstract
Dekkera bruxellensis has been shown to outcompete an initial inoculum of Saccharomyces cerevisiae in several ethanol production plants, which nevertheless had a high efficiency in one of the monitored processes. Co-occurrence of D. bruxellensis with lactic acid bacteria (LAB) Lactobacillus vini has been observed. The aim of this thesis was to broaden the knowledge on D. bruxellensis physiology in respect to its high competitiveness.
Global gene expression analysis of D. bruxellensis under conditions similar to those in which it outcompeted S. cerevisiae was performed by whole transcriptome sequencing. Low expression of genes involved in glycerol biosynthesis, and expression of NADH-ubiquinone reductase (complex I) are probably the basis for an efficient energy metabolism. Genes of putative high affinity glucose transporters might be involved in the efficient glucose transport of D. bruxellensis.
D. bruxellensis also has a good potential to ferment lignocellulose hydrolysate to ethanol. Adaptation to lignocellulose hydrolysate inhibitors by pre-cultivation was demonstrated. Adapted cells had a shorter lag phase and produced higher amounts of ethanol compared to non-adapted cells.
The role of L. vini during co-cultivation with D. bruxellensis or S. cerevisiae was also investigated. Formation of LAB–yeast cell aggregates consisting of a bacterial core with an outer layer of yeast cells was identified. It was noted that addition of mannose to the aggregates dissolved them, but higher mannose amounts were required to inhibit co-flocculation between L. vini and S. cerevisiae compared to L. vini and D. bruxellensis.
Growth and metabolite profiles of D. bruxellensis during cultivation on different combinations of carbon and nitrogen sources were studied. Repression of genes involved in nitrate assimilation in D. bruxellensis under oxygen-limited conditions in presence of ammonium was shown.
In conclusion, D. bruxellensis has a great potential for industrial ethanol production due to a highly efficient energy metabolism, adaptability to lignocellulose hydrolysate, utilisation of an alternative nitrogen source and robustness against bacterial contaminants.
Authors/Creators: | Tiukova, Ievgeniia | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|
Title: | Dekkera bruxellensis, a non-conventional ethanol production yeast | ||||||||||
Subtitle: | studies on physiology, transcriptomics and interactions with industrial microbial isolates | ||||||||||
Series Name/Journal: | Acta Universitatis Agriculturae Sueciae | ||||||||||
Year of publishing : | 16 May 2014 | ||||||||||
Number: | 2014:40 | ||||||||||
Number of Pages: | 73 | ||||||||||
Papers/manuscripts: |
| ||||||||||
Place of Publication: | Uppsala | ||||||||||
Publisher: | Dept. of Microbiology, Swedish University of Agricultural Sciences | ||||||||||
ISBN for printed version: | 978-91-576-8028-0 | ||||||||||
ISBN for electronic version: | 978-91-576-8029-7 | ||||||||||
ISSN: | 1652-6880 | ||||||||||
Language: | English | ||||||||||
Publication Type: | Doctoral thesis | ||||||||||
Full Text Status: | Public | ||||||||||
Agris subject categories.: | P Natural resources > P06 Renewable energy resources X Agricola extesions > X30 Life sciences | ||||||||||
Subjects: | (A) Swedish standard research categories 2011 > 1 Natural sciences > 106 Biological Sciences (Medical to be 3 and Agricultural to be 4) > Microbiology (Microbiology in the medical area to be 30109) (A) Swedish standard research categories 2011 > 2 Engineering and Technology > 209 Industrial Biotechnology > Bioenergy | ||||||||||
Agrovoc terms: | yeasts, saccharomyces cerevisiae, lactobacillus, lactic acid bacteria , ethanol, alcoholic fermentation, renewable energy, gene expression | ||||||||||
Keywords: | Dekkera bruxellensis, Saccharomyces cerevisiae, Lactobacillus vini, bioenergy, ethanol production, microbial interaction, transcriptome, gene expression | ||||||||||
URN:NBN: | urn:nbn:se:slu:epsilon-e-1906 | ||||||||||
Permanent URL: | http://urn.kb.se/resolve?urn=urn:nbn:se:slu:epsilon-e-1906 | ||||||||||
ID Code: | 11188 | ||||||||||
Faculty: | NJ - Fakulteten för naturresurser och jordbruksvetenskap | ||||||||||
Department: | (NL, NJ) > Dept. of Microbiology (until 161231) | ||||||||||
External funders: | Energimyndigheten | ||||||||||
Deposited By: | Ievgeniia Tiukova | ||||||||||
Deposited On: | 19 May 2014 07:48 | ||||||||||
Metadata Last Modified: | 13 Dec 2014 21:56 |
Repository Staff Only: item control page