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Suzuki A, Fujii H, Hoshida H, Akada R. Gene expression analysis using strains constructed by NHEJ-mediated one-step promoter cloning in the yeast Kluyveromyces marxianus. FEMS Yeast Res 2015; 15:fov059. [PMID: 26136515 DOI: 10.1093/femsyr/fov059] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/26/2015] [Indexed: 01/02/2023] Open
Abstract
Gene expression analysis provides valuable information to evaluate cellular state. Unlike quantitative mRNA analysis techniques like reverse-transcription PCR and microarray, expression analysis using a reporter gene has not been commonly used for multiple-gene analysis, probably due to the difficulty in preparing multiple reporter-gene constructs. To circumvent this problem, we developed a novel one-step reporter-gene construction system mediated by non-homologous end joining (NHEJ) in the yeast Kluyveromyces marxianus. As a selectable reporter gene, the ScURA3 selection marker was fused in frame with a red fluorescent gene yEmRFP (ScURA3:yEmRFP). The N-terminally truncated ScURA3:yEmRFP fragment was prepared by PCR. Promoter sequences were also prepared by PCR using primers containing the sequence of the deleted ScURA3 N-terminus to attach at their 3(') ends. The two DNA fragments were used for the transformation of a ura3(-) strain of K. marxianus, in which two DNA fragments are randomly joined and integrated into the chromosome through NHEJ. Only the correctly aligned fragments produced transformants on uracil-deficient medium and expressed red fluorescence under the control of the introduced promoters. A total of 36 gene promoters involved in glycolysis and other pathways were analyzed. Fluorescence measurements of these strains allowed real-time gene expression analysis in different culture conditions.
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Affiliation(s)
- Ayako Suzuki
- Department of Applied Molecular Bioscience, Graduate School of Medicine, Yamaguchi University, Ube 755-8611, Japan
| | - Hiroshi Fujii
- Department of Applied Molecular Bioscience, Graduate School of Medicine, Yamaguchi University, Ube 755-8611, Japan
| | - Hisashi Hoshida
- Department of Applied Molecular Bioscience, Graduate School of Medicine, Yamaguchi University, Ube 755-8611, Japan Research Center for Thermotolerant Microbial Resources, Yamaguchi University, Yamaguchi 753-8315, Japan Yamaguchi University Biomedical Engineering Center, Ube 755-8611, Japan
| | - Rinji Akada
- Department of Applied Molecular Bioscience, Graduate School of Medicine, Yamaguchi University, Ube 755-8611, Japan Research Center for Thermotolerant Microbial Resources, Yamaguchi University, Yamaguchi 753-8315, Japan Yamaguchi University Biomedical Engineering Center, Ube 755-8611, Japan
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52
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Zhang J, Zhang B, Wang D, Gao X, Sun L, Hong J. Rapid ethanol production at elevated temperatures by engineered thermotolerant Kluyveromyces marxianus via the NADP(H)-preferring xylose reductase-xylitol dehydrogenase pathway. Metab Eng 2015; 31:140-52. [PMID: 26253204 DOI: 10.1016/j.ymben.2015.07.008] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2015] [Revised: 06/22/2015] [Accepted: 07/27/2015] [Indexed: 11/17/2022]
Abstract
Conversion of xylose to ethanol by yeasts is a challenge because of the redox imbalances under oxygen-limited conditions. The thermotolerant yeast Kluyveromyces marxianus grows well with xylose as a carbon source at elevated temperatures, but its xylose fermentation ability is weak. In this study, a combination of the NADPH-preferring xylose reductase (XR) from Neurospora crassa and the NADP(+)-preferring xylitol dehydrogenase (XDH) mutant from Scheffersomyces stipitis (Pichia stipitis) was constructed. The xylose fermentation ability and redox balance of the recombinant strains were improved significantly by over-expression of several downstream genes. The intracellular concentrations of coenzymes and the reduced coenzyme/oxidized coenzyme ratio increased significantly in these metabolic strains. The byproducts, such as glycerol and acetic acid, were significantly reduced by the disruption of glycerol-3-phosphate dehydrogenase (GPD1). The resulting engineered K. marxianus YZJ088 strain produced 44.95 g/L ethanol from 118.39 g/L xylose with a productivity of 2.49 g/L/h at 42 °C. Additionally, YZJ088 realized glucose and xylose co-fermentation and produced 51.43 g/L ethanol from a mixture of 103.97 g/L xylose and 40.96 g/L glucose with a productivity of 2.14 g/L/h at 42 °C. These promising results validate the YZJ088 strain as an excellent producer of ethanol from xylose through the synthetic xylose assimilation pathway.
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Affiliation(s)
- Jia Zhang
- School of Life Science, University of Science and Technology of China, Hefei, Anhui 230027, PR China; Hefei National Laboratory for Physical Science at the Microscale, Hefei, Anhui 230026, PR China
| | - Biao Zhang
- School of Life Science, University of Science and Technology of China, Hefei, Anhui 230027, PR China; Hefei National Laboratory for Physical Science at the Microscale, Hefei, Anhui 230026, PR China
| | - Dongmei Wang
- School of Life Science, University of Science and Technology of China, Hefei, Anhui 230027, PR China; Hefei National Laboratory for Physical Science at the Microscale, Hefei, Anhui 230026, PR China
| | - Xiaolian Gao
- School of Life Science, University of Science and Technology of China, Hefei, Anhui 230027, PR China; Department of Biology and Biochemistry, University of Houston, Houston, TX 77004-5001, USA; Hefei National Laboratory for Physical Science at the Microscale, Hefei, Anhui 230026, PR China
| | - Lianhong Sun
- School of Life Science, University of Science and Technology of China, Hefei, Anhui 230027, PR China; Hefei National Laboratory for Physical Science at the Microscale, Hefei, Anhui 230026, PR China
| | - Jiong Hong
- School of Life Science, University of Science and Technology of China, Hefei, Anhui 230027, PR China; Hefei National Laboratory for Physical Science at the Microscale, Hefei, Anhui 230026, PR China.
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Complete Genome Sequence of Kluyveromyces marxianus NBRC1777, a Nonconventional Thermotolerant Yeast. GENOME ANNOUNCEMENTS 2015; 3:3/2/e00389-15. [PMID: 25908152 PMCID: PMC4408353 DOI: 10.1128/genomea.00389-15] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
We determined the genome sequence of the thermotolerant yeast Kluyveromyces marxianus strain NBRC1777. The genome of strain NBRC1777 is composed of 4,912 open reading frames (ORFs) on 8 chromosomes, with a total size of 10,895,581 bp, including mitochondrial DNA.
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Li Y, Tian P. Contemplating 3-Hydroxypropionic Acid Biosynthesis in Klebsiella pneumoniae. Indian J Microbiol 2015; 55:131-9. [PMID: 25805899 DOI: 10.1007/s12088-015-0513-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Accepted: 01/09/2015] [Indexed: 11/30/2022] Open
Abstract
3-Hydroxypropionic acid (3-HP) is a commercially valuable platform chemical from which an array of C3 compounds can be generated. Klebsiella pneumoniae has been considered a promising species for biological production of 3-HP. Despite a wealth of reports related to 3-HP biosynthesis in K. pneumoniae, its commercialization is still in infancy. The major hurdle hindering 3-HP overproduction lies in the poor understanding of glycerol dissimilation in K. pneumoniae. To surmount this problem, this review aims to portray a picture of 3-HP biosynthesis, involving 3-HP-synthesizing strains, biochemical attributes, metabolic pathways and key enzymes. Inspired by the state-of-the-art advances in metabolic engineering and synthetic biology, here we advocate protocols for overproducing 3-HP in K. pneumoniae. These protocols range from cofactor regeneration, alleviation of metabolite toxicity, genome editing, remodeling of transport system, to carbon flux partition via logic gate. The feasibility for these protocols was also discussed.
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Affiliation(s)
- Ying Li
- Beijing Key Lab of Bioprocess, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, 100029 People's Republic of China
| | - Pingfang Tian
- Beijing Key Lab of Bioprocess, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, 100029 People's Republic of China
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Lertwattanasakul N, Kosaka T, Hosoyama A, Suzuki Y, Rodrussamee N, Matsutani M, Murata M, Fujimoto N, Tsuchikane K, Limtong S, Fujita N, Yamada M. Genetic basis of the highly efficient yeast Kluyveromyces marxianus: complete genome sequence and transcriptome analyses. BIOTECHNOLOGY FOR BIOFUELS 2015; 8:47. [PMID: 25834639 PMCID: PMC4381506 DOI: 10.1186/s13068-015-0227-x] [Citation(s) in RCA: 113] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2014] [Accepted: 02/19/2015] [Indexed: 05/07/2023]
Abstract
BACKGROUND High-temperature fermentation technology with thermotolerant microbes has been expected to reduce the cost of bioconversion of cellulosic biomass to fuels or chemicals. Thermotolerant Kluyveromyces marxianus possesses intrinsic abilities to ferment and assimilate a wide variety of substrates including xylose and to efficiently produce proteins. These capabilities have been found to exceed those of the traditional ethanol producer Saccharomyces cerevisiae or lignocellulose-bioconvertible ethanologenic Scheffersomyces stipitis. RESULTS The complete genome sequence of K. marxianus DMKU 3-1042 as one of the most thermotolerant strains in the same species has been determined. A comparison of its genomic information with those of other yeasts and transcriptome analysis revealed that the yeast bears beneficial properties of temperature resistance, wide-range bioconversion ability, and production of recombinant proteins. The transcriptome analysis clarified distinctive metabolic pathways under three different growth conditions, static culture, high temperature, and xylose medium, in comparison to the control condition of glucose medium under a shaking condition at 30°C. Interestingly, the yeast appears to overcome the issue of reactive oxygen species, which tend to accumulate under all three conditions. CONCLUSIONS This study reveals many gene resources for the ability to assimilate various sugars in addition to species-specific genes in K. marxianus, and the molecular basis of its attractive traits for industrial applications including high-temperature fermentation. Especially, the thermotolerance trait may be achieved by an integrated mechanism consisting of various strategies. Gene resources and transcriptome data of the yeast are particularly useful for fundamental and applied researches for innovative applications.
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Affiliation(s)
- Noppon Lertwattanasakul
- />Applied Molecular Bioscience, Graduate School of Medicine, Yamaguchi University, Ube, 755-8505 Japan
- />Department of Microbiology, Faculty of Science, Kasetsart University, Bangkok, 10900 Thailand
| | - Tomoyuki Kosaka
- />Department of Biological Chemistry, Faculty of Agriculture, Yamaguchi University, Yamaguchi, 753-8515 Japan
| | - Akira Hosoyama
- />National Institute of Technology and Evaluation, Shibuya-ku, Tokyo 151-0066 Japan
| | - Yutaka Suzuki
- />Department of Medical Genome Sciences, The University of Tokyo, Chiba, 277-8562 Japan
| | - Nadchanok Rodrussamee
- />Applied Molecular Bioscience, Graduate School of Medicine, Yamaguchi University, Ube, 755-8505 Japan
- />Department of Biology, Faculty of Science, Chiang Mai University, Chiang Mai, 50200 Thailand
| | - Minenosuke Matsutani
- />Department of Biological Chemistry, Faculty of Agriculture, Yamaguchi University, Yamaguchi, 753-8515 Japan
| | - Masayuki Murata
- />Applied Molecular Bioscience, Graduate School of Medicine, Yamaguchi University, Ube, 755-8505 Japan
| | - Naoko Fujimoto
- />Applied Molecular Bioscience, Graduate School of Medicine, Yamaguchi University, Ube, 755-8505 Japan
| | - Keiko Tsuchikane
- />National Institute of Technology and Evaluation, Shibuya-ku, Tokyo 151-0066 Japan
| | - Savitree Limtong
- />Department of Microbiology, Faculty of Science, Kasetsart University, Bangkok, 10900 Thailand
| | - Nobuyuki Fujita
- />National Institute of Technology and Evaluation, Shibuya-ku, Tokyo 151-0066 Japan
| | - Mamoru Yamada
- />Applied Molecular Bioscience, Graduate School of Medicine, Yamaguchi University, Ube, 755-8505 Japan
- />Department of Biological Chemistry, Faculty of Agriculture, Yamaguchi University, Yamaguchi, 753-8515 Japan
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Integrated Automation for Continuous High-Throughput Synthetic Chromosome Assembly and Transformation to Identify Improved Yeast Strains for Industrial Production of Biofuels and Bio-based Chemicals. Fungal Biol 2015. [DOI: 10.1007/978-3-319-10503-1_16] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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57
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Albuquerque TLD, da Silva IJ, de Macedo GR, Rocha MVP. Biotechnological production of xylitol from lignocellulosic wastes: A review. Process Biochem 2014. [DOI: 10.1016/j.procbio.2014.07.010] [Citation(s) in RCA: 101] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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58
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Hughes SR, López-Núñez JC, Jones MA, Moser BR, Cox EJ, Lindquist M, Galindo-Leva LA, Riaño-Herrera NM, Rodriguez-Valencia N, Gast F, Cedeño DL, Tasaki K, Brown RC, Darzins A, Brunner L. Sustainable conversion of coffee and other crop wastes to biofuels and bioproducts using coupled biochemical and thermochemical processes in a multi-stage biorefinery concept. Appl Microbiol Biotechnol 2014; 98:8413-31. [PMID: 25204861 PMCID: PMC4192581 DOI: 10.1007/s00253-014-5991-1] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2014] [Revised: 07/24/2014] [Accepted: 07/25/2014] [Indexed: 01/15/2023]
Abstract
The environmental impact of agricultural waste from the processing of food and feed crops is an increasing concern worldwide. Concerted efforts are underway to develop sustainable practices for the disposal of residues from the processing of such crops as coffee, sugarcane, or corn. Coffee is crucial to the economies of many countries because its cultivation, processing, trading, and marketing provide employment for millions of people. In coffee-producing countries, improved technology for treatment of the significant amounts of coffee waste is critical to prevent ecological damage. This mini-review discusses a multi-stage biorefinery concept with the potential to convert waste produced at crop processing operations, such as coffee pulping stations, to valuable biofuels and bioproducts using biochemical and thermochemical conversion technologies. The initial bioconversion stage uses a mutant Kluyveromyces marxianus yeast strain to produce bioethanol from sugars. The resulting sugar-depleted solids (mostly protein) can be used in a second stage by the oleaginous yeast Yarrowia lipolytica to produce bio-based ammonia for fertilizer and are further degraded by Y. lipolytica proteases to peptides and free amino acids for animal feed. The lignocellulosic fraction can be ground and treated to release sugars for fermentation in a third stage by a recombinant cellulosic Saccharomyces cerevisiae, which can also be engineered to express valuable peptide products. The residual protein and lignin solids can be jet cooked and passed to a fourth-stage fermenter where Rhodotorula glutinis converts methane into isoprenoid intermediates. The residues can be combined and transferred into pyrocracking and hydroformylation reactions to convert ammonia, protein, isoprenes, lignins, and oils into renewable gas. Any remaining waste can be thermoconverted to biochar as a humus soil enhancer. The integration of multiple technologies for treatment of coffee waste has the potential to contribute to economic and environmental sustainability.
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Affiliation(s)
- Stephen R Hughes
- Agricultural Research Service (ARS), National Center for Agricultural Utilization Research (NCAUR), Renewable Product Technology (RPT) Research Unit, United States Department of Agriculture (USDA), 1815 North University Street, Peoria, IL, 61604, USA,
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59
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Kuloyo OO, du Preez JC, García-Aparicio MDP, Kilian SG, Steyn L, Görgens J. Opuntia ficus-indica cladodes as feedstock for ethanol production by Kluyveromyces marxianus and Saccharomyces cerevisiae. World J Microbiol Biotechnol 2014; 30:3173-83. [PMID: 25248867 PMCID: PMC4210634 DOI: 10.1007/s11274-014-1745-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2013] [Accepted: 09/17/2014] [Indexed: 11/05/2022]
Abstract
The feasibility of ethanol production using an enzymatic hydrolysate of pretreated cladodes of Opuntia ficus-indica (prickly pear cactus) as carbohydrate feedstock was investigated, including a comprehensive chemical analysis of the cladode biomass and the effects of limited aeration on the fermentation profiles and sugar utilization. The low xylose and negligible mannose content of the cladode biomass used in this study suggested that the hemicellulose structure of the O. ficus-indica cladode was atypical of hardwood or softwood hemicelluloses. Separate hydrolysis and fermentation and simultaneous saccharification and fermentation procedures using Kluyveromyces marxianus and Saccharomyces cerevisiae at 40 and 35 °C, respectively, gave similar ethanol yields under non-aerated conditions. In oxygen-limited cultures K. marxianus exhibited almost double the ethanol productivity compared to non-aerated cultures, although after sugar depletion utilization of the produced ethanol was evident. Ethanol concentrations of up to 19.5 and 20.6 g l−1 were obtained with K. marxianus and S. cerevisiae, respectively, representing 66 and 70 % of the theoretical yield on total sugars in the hydrolysate. Because of the low xylan content of the cladode biomass, a yeast capable of xylose fermentation might not be a prerequisite for ethanol production. K. marxianus, therefore, has potential as an alternative to S. cerevisiae for bioethanol production. However, the relatively low concentration of fermentable sugars in the O. ficus-indica cladode hydrolysate presents a technical constraint for commercial exploitation.
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Affiliation(s)
- Olukayode O Kuloyo
- Department of Microbial, Biochemical and Food Biotechnology, University of the Free State, P.O. Box 339, Bloemfontein, 9300, South Africa
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Draft Genome Sequence of Kluyveromyces marxianus Strain DMB1, Isolated from Sugarcane Bagasse Hydrolysate. GENOME ANNOUNCEMENTS 2014; 2:2/4/e00733-14. [PMID: 25059876 PMCID: PMC4110234 DOI: 10.1128/genomea.00733-14] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
We determined the genome sequence of a thermotolerant yeast, Kluyveromyces marxianus strain DMB1, isolated from sugarcane bagasse hydrolysate, and the sequence provides further insights into the genomic differences between this strain and other reported K. marxianus strains. The genome described here is composed of 11,165,408 bases and has 4,943 protein-coding genes.
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61
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Camargo D, Gomes SD, Sene L. Ethanol production from sunflower meal biomass by simultaneous saccharification and fermentation (SSF) with Kluyveromyces marxianus ATCC 36907. Bioprocess Biosyst Eng 2014; 37:2235-42. [PMID: 24794173 DOI: 10.1007/s00449-014-1201-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2014] [Accepted: 04/15/2014] [Indexed: 10/25/2022]
Abstract
The lignocellulosic materials are considered promising renewable resources for ethanol production, but improvements in the processes should be studied to reduce operating costs. Thus, the appropriate enzyme loading for cellulose saccharification is critical for process economics. This study aimed at evaluating the concentration of cellulase and β-glucosidase in the production of bioethanol by simultaneous saccharification and fermentation (SSF) of sunflower meal biomass. The sunflower biomass was pretreated with 6% H2SO4 (w/v), at 121 °C, for 20 min, for hemicellulose removal and delignificated with 1% NaOH. SSF was performed with Kluyveromyces marxianus ATCC 36907, at 38 °C, 150 rpm, for 72 h, with different enzyme concentrations (Cellulase Complex NS22086-10, 15 and 20 FPU/gsubstrate and β-Glucosidase NS22118, with a cellulase to β-glucosidase ratio of 1.5:1; 2:1 and 3:1). The best condition for ethanol production was cellulase 20 FPU/gsubstrate and β-glucosidase 13.3 CBU/gsubstrate, resulting in 27.88 g/L ethanol, yield of 0.47 g/g and productivity of 0.38 g/L h. Under this condition the highest enzymatic conversion of cellulose to glucose was attained (87.06%).
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Affiliation(s)
- Danielle Camargo
- Post-Graduate Program in Agricultural Engineering, PGEAGRI, Center of Exact and Technological Sciences, Western Paraná State University, Rua Universitária, 2069, Cascavel-PR, Cascavel, Paraná, CEP 85819-110, Brazil,
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Löser C, Urit T, Bley T. Perspectives for the biotechnological production of ethyl acetate by yeasts. Appl Microbiol Biotechnol 2014; 98:5397-415. [DOI: 10.1007/s00253-014-5765-9] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2014] [Revised: 04/07/2014] [Accepted: 04/08/2014] [Indexed: 12/18/2022]
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63
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Signori L, Passolunghi S, Ruohonen L, Porro D, Branduardi P. Effect of oxygenation and temperature on glucose-xylose fermentation in Kluyveromyces marxianus CBS712 strain. Microb Cell Fact 2014; 13:51. [PMID: 24712908 PMCID: PMC3991920 DOI: 10.1186/1475-2859-13-51] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2014] [Accepted: 04/04/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The yeast Kluyveromyces marxianus features specific traits that render it attractive for industrial applications. These include production of ethanol which, together with thermotolerance and the ability to grow with a high specific growth rate on a wide range of substrates, could make it an alternative to Saccharomyces cerevisiae as an ethanol producer. However, its ability to co-ferment C5 and C6 sugars under oxygen-limited conditions is far from being fully characterized. RESULTS In the present study, K. marxianus CBS712 strain was cultivated in defined medium with glucose and xylose as carbon source. Ethanol fermentation and sugar consumption of CBS712 were investigated under different oxygen supplies (1.75%, 11.00% and 20.95% of O2) and different temperatures (30°C and 41°C). By decreasing oxygen supply, independently from the temperature, both biomass production as well as sugar utilization rate were progressively reduced. In all the tested conditions xylose consumption followed glucose exhaustion. Therefore, xylose metabolism was mainly affected by oxygen depletion. Loss in cell viability cannot explain the decrease in sugar consumption rates, as demonstrated by single cell analyses, while cofactor imbalance is commonly considered as the main cause of impairment of the xylose reductase (KmXR) - xylitol dehydrogenase (KmXDH) pathway. Remarkably, when these enzyme activities were assayed in vitro, a significant decrease was observed together with oxygen depletion, not ascribed to reduced transcription of the corresponding genes. CONCLUSIONS In the present study both oxygen supply and temperature were shown to be key parameters affecting the fermentation capability of sugars in the K. marxianus CBS712 strain. In particular, a direct correlation was observed between the decreased efficiency to consume xylose with the reduced specific activity of the two main enzymes (KmXR and KmXDH) involved in its catabolism. These data suggest that, in addition to the impairment of the oxidoreductive pathway being determined by the cofactor imbalance, post-transcriptional and/or post-translational regulation of the pathway enzymes contributes to the efficiency of xylose catabolism in micro-aerobic conditions. Overall, the presented work provides novel information on the fermentation capability of the CBS712 strain that is currently considered as the reference strain of the genus K. marxianus.
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Affiliation(s)
| | | | | | | | - Paola Branduardi
- University of Milano Bicocca, Piazza della Scienza 2, 20126 Milan, Italy.
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64
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Physiological characterization of thermotolerant yeast for cellulosic ethanol production. Appl Microbiol Biotechnol 2014; 98:3829-40. [PMID: 24535257 PMCID: PMC3973951 DOI: 10.1007/s00253-014-5580-3] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2013] [Revised: 01/24/2014] [Accepted: 01/28/2014] [Indexed: 11/05/2022]
Abstract
The conversion of lignocellulose into fermentable sugars is considered a promising alternative for increasing ethanol production. Higher fermentation yield has been achieved through the process of simultaneous saccharification and fermentation (SSF). In this study, a comparison was performed between the yeast species Saccharomyces cerevisiae and Kluyveromyces marxianus for their potential use in SSF process. Three strains of S. cerevisiae were evaluated: two are widely used in the Brazilian ethanol industry (CAT-1 and PE-2), and one has been isolated based on its capacity to grow and ferment at 42 °C (LBM-1). In addition, we used thermotolerant strains of K. marxianus. Two strains were obtained from biological collections, ATCC 8554 and CCT 4086, and one strain was isolated based on its fermentative capacity (UFV-3). SSF experiments revealed that S. cerevisiae industrial strains (CAT-1 and PE-2) have the potential to produce cellulosic ethanol once ethanol had presented yields similar to yields from thermotolerant strains. The industrial strains are more tolerant to ethanol and had already been adapted to industrial conditions. Moreover, the study shows that although the K. marxianus strains have fermentative capacities similar to strains of S. cerevisiae, they have low tolerance to ethanol. This characteristic is an important target for enhancing the performance of this yeast in ethanol production.
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65
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Yarimizu T, Nonklang S, Nakamura J, Tokuda S, Nakagawa T, Lorreungsil S, Sutthikhumpha S, Pukahuta C, Kitagawa T, Nakamura M, Cha-aim K, Limtong S, Hoshida H, Akada R. Identification of auxotrophic mutants of the yeastKluyveromyces marxianusby non-homologous end joining-mediated integrative transformation with genes fromSaccharomyces cerevisiae. Yeast 2013; 30:485-500. [DOI: 10.1002/yea.2985] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2013] [Revised: 10/11/2013] [Accepted: 10/14/2013] [Indexed: 12/23/2022] Open
Affiliation(s)
- Tohru Yarimizu
- Department of Applied Molecular Bioscience, Graduate School of Medicine; Yamaguchi University; Tokiwadai Ube Japan
| | - Sanom Nonklang
- Department of Biological Science, Faculty of Science; Ubonratchathani University; Warinchumrap Ubonratchathani Thailand
| | - Junpei Nakamura
- Department of Applied Molecular Bioscience, Graduate School of Medicine; Yamaguchi University; Tokiwadai Ube Japan
| | - Shuya Tokuda
- Department of Applied Molecular Bioscience, Graduate School of Medicine; Yamaguchi University; Tokiwadai Ube Japan
| | - Takaaki Nakagawa
- Department of Applied Molecular Bioscience, Graduate School of Medicine; Yamaguchi University; Tokiwadai Ube Japan
| | - Sasithorn Lorreungsil
- Department of Biological Science, Faculty of Science; Ubonratchathani University; Warinchumrap Ubonratchathani Thailand
| | - Surasit Sutthikhumpha
- Department of Biological Science, Faculty of Science; Ubonratchathani University; Warinchumrap Ubonratchathani Thailand
| | - Charida Pukahuta
- Department of Biological Science, Faculty of Science; Ubonratchathani University; Warinchumrap Ubonratchathani Thailand
| | - Takao Kitagawa
- Department of Applied Molecular Bioscience, Graduate School of Medicine; Yamaguchi University; Tokiwadai Ube Japan
| | - Mikiko Nakamura
- Innovation Center; Yamaguchi University; Tokiwadai Ube Japan
| | - Kamonchai Cha-aim
- Faculty of Agricultural Product Innovation and Technology; Srinakharinwirot University; Wattana Bangkok Thailand
| | - Savitree Limtong
- Department of Microbiology, Faculty of Science; Kasetsart University; Bangkok Thailand
| | - Hisashi Hoshida
- Department of Applied Molecular Bioscience, Graduate School of Medicine; Yamaguchi University; Tokiwadai Ube Japan
| | - Rinji Akada
- Department of Applied Molecular Bioscience, Graduate School of Medicine; Yamaguchi University; Tokiwadai Ube Japan
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Castro RCA, Roberto IC. Selection of a Thermotolerant Kluyveromyces marxianus Strain with Potential Application for Cellulosic Ethanol Production by Simultaneous Saccharification and Fermentation. Appl Biochem Biotechnol 2013; 172:1553-64. [DOI: 10.1007/s12010-013-0612-5] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2013] [Accepted: 10/28/2013] [Indexed: 11/25/2022]
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67
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Goshima T, Negi K, Tsuji M, Inoue H, Yano S, Hoshino T, Matsushika A. Ethanol fermentation from xylose by metabolically engineered strains of Kluyveromyces marxianus. J Biosci Bioeng 2013; 116:551-4. [DOI: 10.1016/j.jbiosc.2013.05.010] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2013] [Revised: 04/18/2013] [Accepted: 05/08/2013] [Indexed: 11/26/2022]
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68
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Hughes SR, Bang SS, Cox EJ, Schoepke A, Ochwat K, Pinkelman R, Nelson D, Qureshi N, Gibbons WR, Kurtzman CP, Bischoff KM, Liu S, Cote GL, Rich JO, Jones MA, Cedeño D, Doran-Peterson J, Riaño-Herrera NM, Rodríguez-Valencia N, López-Núñez JC. Automated UV-C Mutagenesis of Kluyveromyces marxianus NRRL Y-1109 and Selection for Microaerophilic Growth and Ethanol Production at Elevated Temperature on Biomass Sugars. ACTA ACUST UNITED AC 2013; 18:276-90. [DOI: 10.1177/2211068213480037] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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69
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Improved xylose fermentation of Kluyveromyces marxianus at elevated temperature through construction of a xylose isomerase pathway. ACTA ACUST UNITED AC 2013; 40:841-54. [DOI: 10.1007/s10295-013-1282-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2013] [Accepted: 04/26/2013] [Indexed: 10/26/2022]
Abstract
Abstract
To improve the xylose fermentation ability of Kluyveromyces marxianus, a xylose assimilation pathway through xylose isomerase was constructed. The genes encoding xylose reductase (KmXyl1) and xylitol dehydrogenase (KmXyl2) were disrupted in K. marxianus YHJ010 and the resultant strain was named YRL002. A codon-optimized xylose isomerase gene from Orpinomyces was transformed into K. marxianus YRL002 and expressed under GAPDH promoter. The transformant was adapted in the SD medium containing 1 % casamino acid with 2 % xylose as sole carbon source. After 32 times of trans-inoculation, a strain named YRL005, which can grow at a specific growth rate of 0.137/h with xylose as carbon source, was obtained. K. marxianus YRL005 could ferment 30.15 g/l of xylose and produce 11.52 g/l ethanol with a yield of 0.38 g/g, production rate of 0.069 g/l/h at 42 °C, and also could ferment 16.60 g/l xylose to produce 5.21 g/l ethanol with a yield of 0.31 g/g, and production rate of 0.054 g/l h at 45 °C. Co-fermentation with 2 % glucose could not improve the amount and yield of ethanol fermented from xylose obviously, but it could improve the production rate. Furthermore, K. marxianus YRL005 can ferment with the corn cob hydrolysate, which contained 20.04 g/l xylose to produce 8.25 g/l ethanol. It is a good platform to construct thermo-tolerant xylose fermentation yeast.
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70
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Impact of High Temperature on Ethanol Fermentation by Kluyveromyces marxianus Immobilized on Banana Leaf Sheath Pieces. Appl Biochem Biotechnol 2013; 171:806-16. [DOI: 10.1007/s12010-013-0411-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2013] [Accepted: 07/19/2013] [Indexed: 10/26/2022]
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Bioethanol production from Lignocellulosic biomass by a novel Kluyveromyces marxianus strain. Biosci Biotechnol Biochem 2013; 77:1505-10. [PMID: 23832346 DOI: 10.1271/bbb.130173] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The yeast Kluyveromyces marxianus is considered as a potential alternative to Saccharomyces cerevisiae in producing ethanol as a biofuel. In this study, we investigated the ethanol fermentation properties of novel K. marxianus strain DMB1, isolated from bagasse hydrolysates. This strain utilized sorbitol as well as various pentoses and hexoses as single carbon sources under aerobic conditions and produced ethanol from glucose in hydrolysates of the Japanese cedar at 42 °C. Reference strains K. marxianus NBRC1777 and S. cerevisiae BY4743 did not assimilate sorbitol or ferment lignocellulosic hydrolysates to ethanol at this temperature. Thus strain DMB1 appears to be optimal for producing bioethanol at high temperatures, and might provide a valuable means of increasing the efficiency of ethanol fermentation.
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Fermentation of biologically pretreated wheat straw for ethanol production: comparison of fermentative microorganisms and process configurations. Appl Biochem Biotechnol 2013; 170:1838-52. [PMID: 23754562 DOI: 10.1007/s12010-013-0318-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2013] [Accepted: 05/30/2013] [Indexed: 10/26/2022]
Abstract
The pretreatment of lignocellulosic biomass with white-rot fungi to produce bioethanol is an environmentally friendly alternative to the commonly used physico-chemical processes. After biological pretreatment, a solid substrate composed of cellulose, hemicellulose and lignin, the two latter with a composition lower than that of the initial substrate, is obtained. In this study, six microorganisms and four process configurations were utilised to ferment a hydrolysate obtained from wheat straw pretreated with the white-rot fungus Irpex lacteus. To enhance total sugars utilisation, five of these microorganisms are able to metabolise, in addition to glucose, most of the pentoses obtained after the hydrolysis of wheat straw by the application of a mixture of hemicellulolytic and cellulolytic enzymes. The highest overall ethanol yield was obtained with the yeast Pachysolen tannophilus. Its application in combination with the best process configuration yielded 163 mg ethanol per gram of raw wheat straw, which was between 23 and 35 % greater than the yields typically obtained with a conventional bioethanol process, in which wheat straw is pretreated using steam explosion and fermented with the yeast Saccharomyces cerevisiae.
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73
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Evaluation of hardboard manufacturing process wastewater as a feedstream for ethanol production. J Ind Microbiol Biotechnol 2013; 40:671-7. [PMID: 23604526 DOI: 10.1007/s10295-013-1272-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2012] [Accepted: 04/07/2013] [Indexed: 10/26/2022]
Abstract
Waste streams from the wood processing industry can serve as feedstream for ethanol production from biomass residues. Hardboard manufacturing process wastewater (HPW) was evaluated on the basis of monomeric sugar recovery and fermentability as a novel feedstream for ethanol production. Dilute acid hydrolysis, coupled with concentration of the wastewater resulted in a hydrolysate with 66 g/l total fermentable sugars. As xylose accounted for 53 % of the total sugars, native xylose-fermenting yeasts were evaluated for their ability to produce ethanol from the hydrolysate. The strains selected were, in decreasing order by ethanol yields from xylose (Y p/s, based on consumed sugars), Scheffersomyces stipitis ATCC 58785 (CBS 6054), Pachysolen tannophilus ATCC 60393, and Kluyveromyces marxianus ATCC 46537. The yeasts were compared on the basis of substrate utilization and ethanol yield during fermentations of the hydrolysate, measured using an HPLC. S. stipitis, P. tannophilus, and K. marxianus produced 0.34, 0.31, and 0.36 g/g, respectively. The yeasts were able to utilize between 58 and 75 % of the available substrate. S. stipitis outperformed the other yeast during the fermentation of the hydrolysate; consuming the highest concentration of available substrate and producing the highest ethanol concentration in 72 h. Due to its high sugar content and low inhibitor levels after hydrolysis, it was concluded that HPW is a suitable feedstream for ethanol production by S. stipitis.
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Improving ethanol and xylitol fermentation at elevated temperature through substitution of xylose reductase in Kluyveromyces marxianus. J Ind Microbiol Biotechnol 2013; 40:305-16. [PMID: 23392758 DOI: 10.1007/s10295-013-1230-5] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2012] [Accepted: 01/09/2013] [Indexed: 10/27/2022]
Abstract
Thermo-tolerant yeast Kluyveromyces marxianus is able to utilize a wide range of substrates, including xylose; however, the xylose fermentation ability is weak because of the redox imbalance under oxygen-limited conditions. Alleviating the intracellular redox imbalance through engineering the coenzyme specificity of NADPH-preferring xylose reductase (XR) and improving the expression of XR should promote xylose consumption and fermentation. In this study, the native xylose reductase gene (Kmxyl1) of the K. marxianus strain was substituted with XR or its mutant genes from Pichia stipitis (Scheffersomyces stipitis). The ability of the resultant recombinant strains to assimilate xylose to produce xylitol and ethanol at elevated temperature was greatly improved. The strain YZB014 expressing mutant PsXR N272D, which has a higher activity with both NADPH and NADH as the coenzyme, achieved the best results, and produced 3.55 g l(-1) ethanol and 11.32 g l(-1) xylitol-an increase of 12.24- and 2.70-fold in product at 42 °C, respectively. A 3.94-fold increase of xylose consumption was observed compared with the K. marxianus YHJ010 harboring KmXyl1. However, the strain YZB015 expressing a mutant PsXR K21A/N272D, with which co-enzyme preference was completely reversed from NADPH to NADH, failed to ferment due to the low expression. So in order to improve xylose consumption and fermentation in K. marxianus, both higher activity and co-enzyme specificity change are necessary.
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Lertwattanasakul N, Murata M, Rodrussamee N, Limtong S, Kosaka T, Yamada M. Essentiality of respiratory activity for pentose utilization in thermotolerant yeast Kluyveromyces marxianus DMKU 3-1042. Antonie van Leeuwenhoek 2013; 103:933-45. [PMID: 23338601 DOI: 10.1007/s10482-012-9874-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2012] [Accepted: 12/31/2012] [Indexed: 11/26/2022]
Abstract
By random integrative mutagenesis with a kanMX4 cassette in Kluyveromyces marxianus DMKU 3-1042, we obtained three mutants of COX15, ATP25 and CYC3 encoding a cytochrome oxidase assembly factor (singleton), a transcription factor required for assembly of the Atp9p subunit of mitochondrial ATP synthase and cytochrome c heme lyase, respectively, as mutants lacking growth capability on xylose and/or arabinose. They exhibited incapability of growth on non-fermentable carbon sources, such as acetate or glycerol, and thermosensitiveness. Their biomass formation in glucose medium was reduced, but ethanol yields were increased with a high ethanol level in the medium, compared to those of the parental strain. Experiments with respiratory inhibitors showed that cox15 and cyc3, but not atp25, were able to grow in glucose medium containing antimycin A and that the atp25 mutant was KCN-resistant. Activities of NADH and ubiquinol oxidases in membrane fractions of each mutant became a half of that of the parent and negligible, respectively, and their remaining NADH oxidase activities were found to be resistant to KCN. Absolute absorption spectral analysis revealed that the peak corresponding to a + a 3 was very small in atp25 and negligible in cox15 and cyc3. These findings suggest that the K. marxianus strain possesses an alternative KCN-resistant oxidase that is located between primary dehydrogenases and the ubiquinone pool and that the respiratory activity is essential for utilization of pentoses.
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Affiliation(s)
- Noppon Lertwattanasakul
- Applied Molecular Bioscience, Graduate School of Medicine, Yamaguchi University, Ube, 755-8505, Japan.
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Yuangsaard N, Yongmanitchai W, Yamada M, Limtong S. Selection and characterization of a newly isolated thermotolerant Pichia kudriavzevii strain for ethanol production at high temperature from cassava starch hydrolysate. Antonie van Leeuwenhoek 2012; 103:577-88. [PMID: 23132277 DOI: 10.1007/s10482-012-9842-8] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2012] [Accepted: 10/24/2012] [Indexed: 11/30/2022]
Abstract
Pichia kudriavzevii DMKU 3-ET15 was isolated from traditional fermented pork sausage by an enrichment technique in a yeast extract peptone dextrose (YPD) broth, supplemented with 4 % (v/v) ethanol at 40 °C and selected based on its ethanol fermentation ability at 40 °C in YPD broth composed of 16 % glucose, and in a cassava starch hydrolysate medium composed of cassava starch hydrolysate adjusted to 16 % glucose. The strain produced ethanol from cassava starch hydrolysate at a high temperature up to 45 °C, but the optimal temperature for ethanol production was at 40 °C. Ethanol production by this strain using shaking flask cultivation was the highest in a medium containing cassava starch hydrolysate adjusted to 18 % glucose, 0.05 % (NH(4))(2)SO(4), 0.09 % yeast extract, 0.05 % KH(2)PO(4), and 0.05 % MgSO(4)·7H(2)O, with a pH of 5.0 at 40 °C. The highest ethanol concentration reached 7.86 % (w/v) after 24 h, with productivity of 3.28 g/l/h and yield of 85.4 % of the theoretical yield. At 42 °C, ethanol production by this strain became slightly lower, while at 45 °C only 3.82 % (w/v) of ethanol, 1.27 g/l/h productivity and 41.5 % of the theoretical yield were attained. In a study on ethanol production in a 2.5-l jar fermenter with an agitation speed of 300 rpm and an aeration rate of 0.1 vvm throughout the fermentation, P. kudriavzevii DMKU 3-ET15 yielded a final ethanol concentration of 7.35 % (w/v) after 33 h, a productivity of 2.23 g/l/h and a yield of 79.9 % of the theoretical yield.
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Affiliation(s)
- Napatchanok Yuangsaard
- Department of Microbiology, Faculty of Science, Kasetsart University, Bangkok, 10900, Thailand
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Tanimura A, Nakamura T, Watanabe I, Ogawa J, Shima J. Isolation of a novel strain of Candida shehatae for ethanol production at elevated temperature. SPRINGERPLUS 2012; 1:27. [PMID: 23961357 PMCID: PMC3725896 DOI: 10.1186/2193-1801-1-27] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/12/2012] [Accepted: 10/02/2012] [Indexed: 11/10/2022]
Abstract
Considering the cost-effectiveness of bioethanol production, there is a need for a yeast strain which can convert glucose and xylose into ethanol at elevated temperatures. We succeeded in isolating a yeast strain, designated strain ATY839, which was capable of ethanolic fermentation at temperatures above those previously reported for yeasts able to ferment both glucose and xylose. Strain ATY839 was capable of producing a substantial amount of ethanol at up to 37°C from 2% glucose or 2% xylose. The results of a phylogenetic analysis suggest that strain ATY839 belongs to Candida shehatae. In additional, ethanol production from rice straw by strain ATY839 was examined. Compared with the control strains (Saccharomyces cerevisiae NBRC 0224, Scheffersomyces stipitis NBRC 10063, and C. shehatae ATCC 22984), strain ATY839 produced more ethanol in SSF even at 37°C. The theoretical maximum yield of strain ATY839 was 71.6% at 24 h. Thus, strain ATY839 is considered to be the most tolerant to high temperature of the C. shehatae strains.
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Affiliation(s)
- Ayumi Tanimura
- Research Division of Microbial Sciences, Kyoto University, Kitashirakawa Oiwake-Cho, Sakyo-ku, Kyoto, 606-8502 Japan
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dos Santos VC, Bragança CRS, Passos FJV, Passos FML. Kinetics of growth and ethanol formation from a mix of glucose/xylose substrate by Kluyveromyces marxianus UFV-3. Antonie van Leeuwenhoek 2012; 103:153-61. [PMID: 22965752 DOI: 10.1007/s10482-012-9794-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2012] [Accepted: 08/09/2012] [Indexed: 11/27/2022]
Abstract
The fermentation of both glucose and xylose is important to maximize ethanol yield from renewable biomass feedstocks. In this article, we analyze growth, sugar consumption, and ethanol formation by the yeast Kluyveromyces marxianus UFV-3 using various glucose and xylose concentrations and also under conditions of reduced respiratory activity. In almost all the conditions analyzed, glucose repressed xylose assimilation and xylose consumption began after glucose had been exhausted. A remarkable difference was observed when mixtures of 5 g L(-1) glucose/20 g L(-1) xylose and 20 g L(-1) glucose/20 g L(-1) xylose were used. In the former, the xylose consumption began immediately after the glucose depletion. Indeed, there was no striking diauxic phase, as observed in the latter condition, in which there was an interval of 30 h between glucose depletion and the beginning of xylose consumption. Ethanol production was always higher in a mixture of glucose and xylose than in glucose alone. The highest ethanol concentration (8.65 g L(-1)) and cell mass concentration (4.42 g L(-1)) were achieved after 8 and 74 h, respectively, in a mixture of 20 g L(-1) glucose/20 g L(-1) xylose. When inhibitors of respiration were added to the medium, glucose repression of xylose consumption was alleviated completely and K. marxianus was able to consume xylose and glucose simultaneously.
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Affiliation(s)
- Valdilene Canazart dos Santos
- Department of Microbiology, Institute for Biotechnology Applied to Agriculture and Animal Science, Federal University of Viçosa, Viçosa, MG, Brazil
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Consolidated bioprocessing and simultaneous saccharification and fermentation of lignocellulose to ethanol with thermotolerant yeast strains. Process Biochem 2012. [DOI: 10.1016/j.procbio.2012.05.004] [Citation(s) in RCA: 120] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Lertwattanasakul N, Rodrussamee N, Suprayogi, Limtong S, Thanonkeo P, Kosaka T, Yamada M. Utilization capability of sucrose, raffinose and inulin and its less-sensitiveness to glucose repression in thermotolerant yeast Kluyveromyces marxianus DMKU 3-1042. AMB Express 2011; 1:20. [PMID: 21920047 PMCID: PMC3222316 DOI: 10.1186/2191-0855-1-20] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2011] [Accepted: 07/19/2011] [Indexed: 11/10/2022] Open
Abstract
Kluyveromyces marxianus possesses a useful potential to assimilate a wide variety of substrates at a high temperature, but the negative effect by coexisting glucose is critical for utilization of biomass containing various sugars. Such a negative effect on the activity of inulinase, which is the sole enzyme to hydrolyze sucrose, raffinose and inulin, has been demonstrated in K. marxianus without analysis at the gene level. To clarify the utilization capability of sucrose, raffinose and inulin and the glucose effect on inulinase in K. marxianus DMKU 3-1042, its growth and metabolite profiles on these sugars were examined with or without glucose under a static condition, in which glucose repression evidently occurs. Consumption of sucrose was not influenced by glucose or 2-deoxyglucose. On the other hand, raffinose and inulin consumption was hampered by glucose at 30°C but hardly hampered at 45°C. Unlike Saccharomyces cerevisiae, increase in glucose concentration had no effect on sucrose utilization. These sugar-specific glucose effects were consistent with the level of inulinase activity but not with that of the KmINU1 transcript, which was repressed in the presence of glucose via KmMig1p. This inconsistency may be due to sufficient activity of inulinase even when glucose is present. Our results encourage us to apply K. marxianus DMKU 3-1042 to high-temperature ethanol fermentation with biomass containing these sugars with glucose.
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