Exploring metal ion metabolisms to improve xylose fermentation in Saccharomyces cerevisiae

The aim of the study was to investigate the influence of a pulsed electric field (PEF) on the level of iron ion accumulation in Saccharomyces cerevisiae cells and to select PEF conditions optimal for the highest uptake of this element. Iron ions were accumulated most efficiently when their source was iron (III) nitrate. When the following conditions of PEF treatment were used: voltage 1500 V, pulse width 10 μs, treatment time 20 min, and a number of pulses 1200, accumulation of iron ions in the cells from a 20 h-culture reached a maximum value of 48.01 mg/g dry mass. Application of the optimal PEF conditions thus increased iron accumulation in cells by 157% as compared to the sample enriched with iron without PEF. The second derivative of the FTIR spectra of iron-loaded and -unloaded yeast cells allowed us to determine the functional groups which may be involved in metal ion binding. The exposure of cells to PEF treatment only slightly influenced the biomass and cell viability. However, iron-enriched yeast (both with or without PEF) showed lower fermentative activity than a control sample. Thus obtained yeast biomass containing a high amount of incorporated iron may serve as an alternative to pharmacological supplementation in the state of iron deficiency.

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Bacterial xylose isomerases from the mammal gut Bacteroidetes cluster function in Saccharomyces cerevisiae for effective xylose fermentation

Microbial Cell Factories ◽

10.1186/s12934-015-0253-1 ◽

2015 ◽

Vol 14 (1) ◽

Cited By ~ 26

Author(s):

Bingyin Peng ◽

Shuangcheng Huang ◽

Tingting Liu ◽

Anli Geng

Keyword(s):

Saccharomyces Cerevisiae ◽

Xylose Fermentation ◽

Cluster Function

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Transcriptomic Changes Induced by Deletion of Transcriptional Regulator GCR2 on Pentose Sugar Metabolism in Saccharomyces cerevisiae

Frontiers in Bioengineering and Biotechnology ◽

10.3389/fbioe.2021.654177 ◽

2021 ◽

Vol 9 ◽

Author(s):

Minhye Shin ◽

Heeyoung Park ◽

Sooah Kim ◽

Eun Joong Oh ◽

Deokyeol Jeong ◽

...

Keyword(s):

Saccharomyces Cerevisiae ◽

Xylose Fermentation ◽

Sugar Metabolism ◽

Pentose Phosphate ◽

Biofuel Production ◽

Rna Seq ◽

Loss Of Function ◽

Lignocellulosic Biofuel ◽

Pentose Sugar ◽

Transcriptomic Changes

Being a microbial host for lignocellulosic biofuel production, Saccharomyces cerevisiae needs to be engineered to express a heterologous xylose pathway; however, it has been challenging to optimize the engineered strain for efficient and rapid fermentation of xylose. Deletion of PHO13 (Δpho13) has been reported to be a crucial genetic perturbation in improving xylose fermentation. A confirmed mechanism of the Δpho13 effect on xylose fermentation is that the Δpho13 transcriptionally activates the genes in the non-oxidative pentose phosphate pathway (PPP). In the current study, we found a couple of engineered strains, of which phenotypes were not affected by Δpho13 (Δpho13-negative), among many others we examined. Genome resequencing of the Δpho13-negative strains revealed that a loss-of-function mutation in GCR2 was responsible for the phenotype. Gcr2 is a global transcriptional factor involved in glucose metabolism. The results of RNA-seq confirmed that the deletion of GCR2 (Δgcr2) led to the upregulation of PPP genes as well as downregulation of glycolytic genes, and changes were more significant under xylose conditions than those under glucose conditions. Although there was no synergistic effect between Δpho13 and Δgcr2 in improving xylose fermentation, these results suggested that GCR2 is a novel knockout target in improving lignocellulosic ethanol production.

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Xylose Fermentation by Saccharomyces cerevisiae: Challenges and Prospects

International Journal of Molecular Sciences ◽

10.3390/ijms17030207 ◽

2016 ◽

Vol 17 (3) ◽

pp. 207 ◽

Cited By ~ 120

Author(s):

Danuza Moysés ◽

Viviane Reis ◽

João Almeida ◽

Lidia Moraes ◽

Fernando Torres

Keyword(s):

Saccharomyces Cerevisiae ◽

Xylose Fermentation

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CzcD Is a Heavy Metal Ion Transporter Involved in Regulation of Heavy Metal Resistance in Ralstonia sp. Strain CH34

Journal of Bacteriology ◽

10.1128/jb.181.22.6876-6881.1999 ◽

1999 ◽

Vol 181 (22) ◽

pp. 6876-6881 ◽

Cited By ~ 137

Author(s):

Andreas Anton ◽

Cornelia Große ◽

Jana Reißmann ◽

Thomas Pribyl ◽

Dietrich H. Nies

Keyword(s):

Saccharomyces Cerevisiae ◽

Heavy Metal ◽

Metal Ion ◽

Constitutive Expression ◽

Heavy Metal Resistance ◽

Metal Resistance ◽

Cation Diffusion ◽

Ion Efflux ◽

Domains Of Life ◽

Membrane Bound

ABSTRACT The Czc system of Ralstonia sp. strain CH34 mediates resistance to cobalt, zinc, and cadmium through ion efflux catalyzed by the CzcCB2A cation-proton antiporter. The CzcD protein is involved in the regulation of the Czc system. It is a membrane-bound protein with at least four transmembrane α-helices and is a member of a subfamily of the cation diffusion facilitator (CDF) protein family, which occurs in all three domains of life. The deletion ofczcD in a Ralstonia sp. led to partially constitutive expression of the Czc system due to an increased transcription of the structural czcCBA genes, both in the absence and presence of inducers. The czcD deletion could be fully complemented in trans by CzcD and two other CDF proteins from Saccharomyces cerevisiae, ZRC1p and COT1p. All three proteins mediated a small but significant resistance to cobalt, zinc, and cadmium in Ralstonia, and this resistance was based on a reduced accumulation of the cations. Thus, CzcD appeared to repress the Czc system by an export of the inducing cations.

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The response mechanisms of industrial Saccharomyces cerevisiae to acetic acid and formic acid during mixed glucose and xylose fermentation

Process Biochemistry ◽

10.1016/j.procbio.2020.01.002 ◽

2020 ◽

Vol 91 ◽

pp. 319-329

Author(s):

Bo Li ◽

Cai-Yun Xie ◽

Bai-Xue Yang ◽

Min Gou ◽

Zi-Yuan Xia ◽

...

Keyword(s):

Saccharomyces Cerevisiae ◽

Acetic Acid ◽

Formic Acid ◽

Xylose Fermentation ◽

Glucose And Xylose Fermentation

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Long-term incomplete xylose fermentation, after glucose exhaustion, with Candida shehatae co-immobilized with Saccharomyces cerevisiae

Microbiological Research ◽

10.1016/j.micres.2006.07.005 ◽

2007 ◽

Vol 162 (3) ◽

pp. 211-218 ◽

Cited By ~ 17

Author(s):

T. Lebeau ◽

T. Jouenne ◽

G.-A. Junter

Keyword(s):

Saccharomyces Cerevisiae ◽

Xylose Fermentation ◽

Candida Shehatae

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gTME for Improved Xylose Fermentation of Saccharomyces cerevisiae

Applied Biochemistry and Biotechnology ◽

10.1007/s12010-008-8431-9 ◽

2008 ◽

Vol 160 (2) ◽

pp. 574-582 ◽

Cited By ~ 37

Author(s):

Hongmei Liu ◽

Ming Yan ◽

Cangang Lai ◽

Lin Xu ◽

Pingkai Ouyang

Keyword(s):

Saccharomyces Cerevisiae ◽

Xylose Fermentation

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Functional Expression of a Bacterial Xylose Isomerase in Saccharomyces cerevisiae

Applied and Environmental Microbiology ◽

10.1128/aem.02522-08 ◽

2009 ◽

Vol 75 (8) ◽

pp. 2304-2311 ◽

Cited By ~ 174

Author(s):

Dawid Brat ◽

Eckhard Boles ◽

Beate Wiedemann

Keyword(s):

Saccharomyces Cerevisiae ◽

Heterologous Expression ◽

Xylose Fermentation ◽

Thermus Thermophilus ◽

Xylose Isomerase ◽

Functional Expression ◽

Yeast Cells ◽

Highly Active ◽

Excellent Starting Point ◽

Starting Point

ABSTRACT In industrial fermentation processes, the yeast Saccharomyces cerevisiae is commonly used for ethanol production. However, it lacks the ability to ferment pentose sugars like d-xylose and l-arabinose. Heterologous expression of a xylose isomerase (XI) would enable yeast cells to metabolize xylose. However, many attempts to express a prokaryotic XI with high activity in S. cerevisiae have failed so far. We have screened nucleic acid databases for sequences encoding putative XIs and finally were able to clone and successfully express a highly active new kind of XI from the anaerobic bacterium Clostridium phytofermentans in S. cerevisiae. Heterologous expression of this enzyme confers on the yeast cells the ability to metabolize d-xylose and to use it as the sole carbon and energy source. The new enzyme has low sequence similarities to the XIs from Piromyces sp. strain E2 and Thermus thermophilus, which were the only two XIs previously functionally expressed in S. cerevisiae. The activity and kinetic parameters of the new enzyme are comparable to those of the Piromyces XI. Importantly, the new enzyme is far less inhibited by xylitol, which accrues as a side product during xylose fermentation. Furthermore, expression of the gene could be improved by adapting its codon usage to that of the highly expressed glycolytic genes of S. cerevisiae. Expression of the bacterial XI in an industrially employed yeast strain enabled it to grow on xylose and to ferment xylose to ethanol. Thus, our findings provide an excellent starting point for further improvement of xylose fermentation in industrial yeast strains.

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