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Shang-tian Yang - One of the best experts on this subject based on the ideXlab platform.
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Recent advances in n -butanol and butyrate production using engineered Clostridium tyrobutyricum
World Journal of Microbiology and Biotechnology, 2020Co-Authors: Teng Bao, Jun Feng, Jufang Wang, Wenyan Jiang, Shang-tian YangAbstract:Acidogenic clostridia naturally producing acetic and butyric acids has attracted high interest as a novel host for butyrate and n-butanol production. Among them, Clostridium tyrobutyricum is a hyper butyrate-producing bacterium, which re-assimilates acetate for butyrate biosynthesis by butyryl-CoA/acetate CoA transferase (CoAT), rather than the phosphotransbutyrylase-butyrate kinase (PTB-BK) pathway widely found in clostridia and other microbial species. To date, C. tyrobutyricum has been engineered to overexpress a heterologous alcohol/aldehyde dehydrogenase, which converts butyryl-CoA to n-butanol. Compared to conventional solventogenic clostridia, which produce acetone, ethanol, and butanol in a biphasic fermentation process, the engineered C. tyrobutyricum with a high metabolic flux toward butyryl-CoA produced n-butanol at a high yield of > 0.30 g/g and titer of > 20 g/L in glucose fermentation. With no acetone production and a high C4/C2 ratio, butanol was the only major fermentation product by the recombinant C. tyrobutyricum, allowing simplified downstream processing for product purification. In this review, novel metabolic engineering strategies to improve n-butanol and butyrate production by C. tyrobutyricum from various substrates, including glucose, xylose, galactose, sucrose, and cellulosic hydrolysates containing the mixture of glucose and xylose, are discussed. Compared to other recombinant hosts such as Clostridium acetobutylicum and Escherichia coli, the engineered C. tyrobutyricum strains with higher butyrate and butanol titers, yields and productivities are the most promising hosts for potential industrial applications.
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n butanol production from lignocellulosic biomass hydrolysates without detoxification by Clostridium tyrobutyricum δack adhe2 in a fibrous bed bioreactor
Bioresource Technology, 2019Co-Authors: Teng Bao, Meng Lin, Jie Dong, Hojae Shim, Shang-tian YangAbstract:Abstract Acetone-butanol-ethanol fermentation suffers from high substrate cost and low butanol titer and yield. In this study, engineered Clostridium tyrobutyricum CtΔ ack - adhE2 immobilized in a fibrous-bed bioreactor was used for butanol production from glucose and xylose present in the hydrolysates of low-cost lignocellulosic biomass including corn fiber, cotton stalk, soybean hull, and sugarcane bagasse. The biomass hydrolysates obtained after acid pretreatment and enzymatic hydrolysis were supplemented with corn steep liquor and used in repeated-batch fermentations. Butanol production with high titer (∼15 g/L), yield (∼0.3 g/g), and productivity (∼0.3 g/L∙h) was obtained from cotton stalk, soybean hull, and sugarcane bagasse hydrolysates, while corn fiber hydrolysate with higher inhibitor contents gave somewhat inferior results. The fermentation process was stable for long-term operation without any noticeable degeneration, demonstrating its potential for industrial application. A techno-economic analysis showed that n -butanol could be produced from lignocellulosic biomass using this novel fermentation process at ∼$2.5/gal for biofuel application.
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Production of n-butanol from cassava bagasse hydrolysate by engineered Clostridium tyrobutyricum overexpressing adhE2: Kinetics and cost analysis
Bioresource Technology, 2019Co-Authors: Jin Huang, Jufang Wang, Meng Lin, Teng Bao, Shang-tian YangAbstract:Abstract The production of biofuels such as butanol is usually limited by the availability of inexpensive raw materials and high substrate cost. Using food crops as feedstock in the biorefinery industry has been criticized for its competition with food supply, causing food shortage and increased food prices. In this study, cassava bagasse as an abundant, renewable, and inexpensive byproduct from the cassava starch industry was used for n-butanol production. Cassava bagasse hydrolysate containing mainly glucose was obtained after treatments with dilute acid and enzymes (glucoamylases and cellulases) and then supplemented with corn steep liquor for use as substrate in repeated-batch fermentation with engineered Clostridium tyrobutyricum CtΔack-adhE2 in a fibrous-bed bioreactor. Stable butanol production with high titer (>15.0 g/L), yield (>0.30 g/g), and productivity (~0.3 g/L∙h) was achieved, demonstrating the feasibility of an economically competitive process for n-butanol production from cassava bagasse for industrial application.
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Production of butyric acid from acid hydrolysate of corn husk in fermentation by Clostridium tyrobutyricum : kinetics and process economic analysis
Biotechnology for Biofuels, 2018Co-Authors: Zhiping Xiao, Shang-tian Yang, Chu Cheng, Teng Bao, Lujie Liu, Bin Wang, Wenjing Tao, Xun Pei, Minqi WangAbstract:Background Butyric acid is an important chemical currently produced from petrochemical feedstocks. Its production from renewable, low-cost biomass in fermentation has attracted large attention in recent years. In this study, the feasibility of corn husk, an abundant agricultural residue, for butyric acid production by using Clostridium tyrobutyricum immobilized in a fibrous bed bioreactor (FBB) was evaluated.
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n butanol production from sucrose and sugarcane juice by engineered Clostridium tyrobutyricum overexpressing sucrose catabolism genes and adhe2
Bioresource Technology, 2017Co-Authors: Jianzhi Zhang, Meng Lin, Qiaojuan Yan, Shang-tian YangAbstract:The production of n-butanol from sugarcane juice by metabolically engineered Clostridium tyrobutyricum Ct(Δack)-pscrBAK overexpressing scr operon genes (scrB, scrA, and scrK) for sucrose catabolism and an aldehyde/alcohol dehydrogenase gene (adhE2) for butanol biosynthesis was studied with corn steep liquor (CSL) as a low-cost nitrogen source. In free cell fermentation, butanol production of ∼16g/L at a yield of 0.31±0.02g/g and productivity of 0.33±0.02g/L·h was obtained from sucrose and yield of 0.24±0.02g/g and productivity of 0.30±0.01g/L·h from sugarcane juice containing sucrose, glucose and fructose. The fermentation was also studied in a fibrous bed bioreactor (FBB) operated in a repeated batch mode for 10 consecutive cycles in 10days, achieving an average butanol yield of 0.21±0.02g/g and productivity of 0.53±0.05g/L·h from sugarcane juice, demonstrating its long-term stability without applying the antibiotic selection pressure.
Jufang Wang - One of the best experts on this subject based on the ideXlab platform.
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Recent advances in n -butanol and butyrate production using engineered Clostridium tyrobutyricum
World Journal of Microbiology and Biotechnology, 2020Co-Authors: Teng Bao, Jun Feng, Jufang Wang, Wenyan Jiang, Shang-tian YangAbstract:Acidogenic clostridia naturally producing acetic and butyric acids has attracted high interest as a novel host for butyrate and n-butanol production. Among them, Clostridium tyrobutyricum is a hyper butyrate-producing bacterium, which re-assimilates acetate for butyrate biosynthesis by butyryl-CoA/acetate CoA transferase (CoAT), rather than the phosphotransbutyrylase-butyrate kinase (PTB-BK) pathway widely found in clostridia and other microbial species. To date, C. tyrobutyricum has been engineered to overexpress a heterologous alcohol/aldehyde dehydrogenase, which converts butyryl-CoA to n-butanol. Compared to conventional solventogenic clostridia, which produce acetone, ethanol, and butanol in a biphasic fermentation process, the engineered C. tyrobutyricum with a high metabolic flux toward butyryl-CoA produced n-butanol at a high yield of > 0.30 g/g and titer of > 20 g/L in glucose fermentation. With no acetone production and a high C4/C2 ratio, butanol was the only major fermentation product by the recombinant C. tyrobutyricum, allowing simplified downstream processing for product purification. In this review, novel metabolic engineering strategies to improve n-butanol and butyrate production by C. tyrobutyricum from various substrates, including glucose, xylose, galactose, sucrose, and cellulosic hydrolysates containing the mixture of glucose and xylose, are discussed. Compared to other recombinant hosts such as Clostridium acetobutylicum and Escherichia coli, the engineered C. tyrobutyricum strains with higher butyrate and butanol titers, yields and productivities are the most promising hosts for potential industrial applications.
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high selectivity butyric acid production from saccharina japonica hydrolysate by Clostridium tyrobutyricum
Industrial & Engineering Chemistry Research, 2020Co-Authors: Xiaolong Guo, Jun Feng, Yanan Zhang, Jufang WangAbstract:Clostridium tyrobutyricum ATCC 25755 is a promising butyric acid-producing strain. However, the existence of acetic acid as a byproduct decreases butyric acid yield and increases downstream process...
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Butyric acid production from spent coffee grounds by engineered Clostridium tyrobutyricum overexpressing galactose catabolism genes.
Bioresource Technology, 2020Co-Authors: Shiwen Qin, Yukai Suo, Zhi Yang, Xuehui Bai, Jufang WangAbstract:Abstract Clostridium tyrobutyricum cannot utilize galactose, which is abundant in lignocellulose and red algae, as a carbon source for butyric acid production. Hence, when using galactose-rich coffee ground hydrolysate as the substrate, the fermentation performance of C. tyrobutyricum is poor. In this work, a recombinant strain, C. tyrobutyricum ATCC 25755/ketp, overexpressing galactose catabolism genes (galK, galE, galT, and galP) from Clostridium acetobutylicum ATCC 824 was constructed for the co-utilization of glucose and galactose. Batch fermentation in the bioreactor showed that ATCC 25755/ketp could efficiently utilize galactose without glucose-induced carbon catabolite repression and consume nearly 100% of the galactose present in the spent coffee ground hydrolysate. Correspondingly, the butyric acid concentration and productivity of ATCC 25755/ketp reached 34.3 g/L and 0.36 g/L·h, respectively, an increase of 78.6% and 56.5% compared with the wild-type strain, indicating its potential for butyric acid production from hydrolysates of inexpensive and galactose-rich biomass.
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Production of n-butanol from cassava bagasse hydrolysate by engineered Clostridium tyrobutyricum overexpressing adhE2: Kinetics and cost analysis
Bioresource Technology, 2019Co-Authors: Jin Huang, Jufang Wang, Meng Lin, Teng Bao, Shang-tian YangAbstract:Abstract The production of biofuels such as butanol is usually limited by the availability of inexpensive raw materials and high substrate cost. Using food crops as feedstock in the biorefinery industry has been criticized for its competition with food supply, causing food shortage and increased food prices. In this study, cassava bagasse as an abundant, renewable, and inexpensive byproduct from the cassava starch industry was used for n-butanol production. Cassava bagasse hydrolysate containing mainly glucose was obtained after treatments with dilute acid and enzymes (glucoamylases and cellulases) and then supplemented with corn steep liquor for use as substrate in repeated-batch fermentation with engineered Clostridium tyrobutyricum CtΔack-adhE2 in a fibrous-bed bioreactor. Stable butanol production with high titer (>15.0 g/L), yield (>0.30 g/g), and productivity (~0.3 g/L∙h) was achieved, demonstrating the feasibility of an economically competitive process for n-butanol production from cassava bagasse for industrial application.
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Butyric acid production from lignocellulosic biomass hydrolysates by engineered Clostridium tyrobutyricum overexpressing Class I heat shock protein GroESL
Bioresource Technology, 2018Co-Authors: Yukai Suo, Xitong Yang, Mengmeng Ren, Zhengping Liao, Hongxin Fu, Jufang WangAbstract:Lignocellulosic biomass is the most abundant and renewable substrate for biological fermentation, but the inhibitors present in the lignocellulosic hydrolysates could severely inhibit the cell growth and productivity of industrial strains. This study confirmed that overexpressing of native groESL in Clostridium tyrobutyricum could significantly improve its tolerance to lignocellulosic hydrolysate-derived inhibitors, especially for phenolic compounds. Consequently, ATCC 25755/groESL showed a better performance in butyric acid fermentation with hydrolysates of corn cob, corn straw, rice straw, wheat straw, soybean hull and soybean straw, respectively. When corn straw and rice straw hydrolysates, which showed strong toxicity to C. tyrobutyricum, were used as the substrates, 29.6 g/L and 30.1 g/L butyric acid were obtained in batch fermentation, increased by 26.5% and 19.4% as compared with the wild-type strain, respectively. And more importantly, the butyric acid productivity reached 0.31 g/L·h (vs. 0.20–0.21 g/L·h for the wild-type strain) due to the shortened lag phase.
Jianzhi Zhang - One of the best experts on this subject based on the ideXlab platform.
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n butanol production from sucrose and sugarcane juice by engineered Clostridium tyrobutyricum overexpressing sucrose catabolism genes and adhe2
Bioresource Technology, 2017Co-Authors: Jianzhi Zhang, Meng Lin, Qiaojuan Yan, Shang-tian YangAbstract:The production of n-butanol from sugarcane juice by metabolically engineered Clostridium tyrobutyricum Ct(Δack)-pscrBAK overexpressing scr operon genes (scrB, scrA, and scrK) for sucrose catabolism and an aldehyde/alcohol dehydrogenase gene (adhE2) for butanol biosynthesis was studied with corn steep liquor (CSL) as a low-cost nitrogen source. In free cell fermentation, butanol production of ∼16g/L at a yield of 0.31±0.02g/g and productivity of 0.33±0.02g/L·h was obtained from sucrose and yield of 0.24±0.02g/g and productivity of 0.30±0.01g/L·h from sugarcane juice containing sucrose, glucose and fructose. The fermentation was also studied in a fibrous bed bioreactor (FBB) operated in a repeated batch mode for 10 consecutive cycles in 10days, achieving an average butanol yield of 0.21±0.02g/g and productivity of 0.53±0.05g/L·h from sugarcane juice, demonstrating its long-term stability without applying the antibiotic selection pressure.
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metabolic engineering of Clostridium tyrobutyricum for n butanol production from sugarcane juice
Applied Microbiology and Biotechnology, 2017Co-Authors: Shang-tian Yang, Jianzhi Zhang, Meng Lin, Qiaojuan Yan, Iching TangAbstract:Clostridium tyrobutyricum is a promising organism for butyrate and n-butanol production, but cannot grow on sucrose. Three genes (scrA, scrB, and scrK) involved in the sucrose catabolic pathway, along with an aldehyde/alcohol dehydrogenase gene, were cloned from Clostridium acetobutylicum and introduced into C. tyrobutyricum (Δack) with acetate kinase knockout. In batch fermentation, the engineered strain Ct(Δack)-pscrBAK produced 14.8–18.8 g/L butanol, with a high butanol/total solvent ratio of ∼0.94 (w/w), from sucrose and sugarcane juice. Moreover, stable high butanol production with a high butanol yield of 0.25 g/g and productivity of 0.28 g/L∙h was obtained in batch fermentation without using antibiotics for selection pressure, suggesting that Ct(Δack)-pscrBAK is genetically stable. Furthermore, sucrose utilization by Ct(Δack)-pscrBAK was not inhibited by glucose, which would usually cause carbon catabolite repression on solventogenic clostridia. Ct(Δack)-pscrBAK is thus advantageous for use in biobutanol production from sugarcane juice and other sucrose-rich feedstocks.
Jong Moon Park - One of the best experts on this subject based on the ideXlab platform.
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Molecular characterization and homologous overexpression of [FeFe]-hydrogenase in Clostridium tyrobutyricum JM1
International Journal of Hydrogen Energy, 2010Co-Authors: Che Ok Jeon, Dae Sung Lee, Seung Yoon Lee, Jong Moon ParkAbstract:Abstract The H 2 -evoving [FeFe]-hydrogenase in Clostridium tyrobutyricum JM1 was isolated to elucidate molecular characterization and modular structure of the hydrogenase. Then, homologous overexpression of the hydrogenase gene was for the first time performed to enhance hydrogen production. The hydA open reading frame (ORF) was 1734-bp, encodes 577 amino acids with a predicted molecular mass of 63,970 Da, and presents 80% and 75% identity at the amino acid level with the [FeFe]-hydrogenase genes of Clostridium kluyveri DSM 555 and Clostridium acetobutylicum ATCC 824, respectively. One histidine residue and 19 cysteine residues, known to fasten one [2Fe–2S] cluster, three [4Fe–4S] clusters and one H-cluster, were conserved in hydA of C. tyrobutyricum . A 2327-bp DNA region containing the ORF and the putative promoter region was amplified and subcloned into a pJIR418 shuttle vector. The gene transfer of the recombinant plasmid into C. tyrobutyricum JM1 was performed by a modified electrotransformation method. Homologous overexpression of the [FeFe]-hydrogenase gene resulted in a 1.7-fold and 1.5-fold increase in hydrogenase activity and hydrogen yield concomitant with the shift of metabolic pathway.
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Effect of Initial Glucose Concentrations on Carbon and Energy Balances in Hydrogen-Producing Clostridium tyrobutyricum JM1
Journal of microbiology and biotechnology, 2009Co-Authors: Dae Sung Lee, Junhoon Kim, Jong Moon ParkAbstract:333.6 mM). Because an understandingof metabolic regulations was required to provide guidancefor further effective metabolic design or optimization, in thiscase, maximizing hydrogen production, carbon and energybalances by C. tyrobutyricum JM1 were determined andapplied in anaerobic glucose metabolism. The overall carbondistribution suggested that initial glucose concentrationshad strong influence on the stoichiometric coefficientsof products and the molar production of ATP on theformation of biomass. C. tyrobutyricum JM1 had a highcapacity for hydrogen production at the initial glucoseconcentration of 222.4 mM with high concentrations ofacetate and butyrate.Keywords: Clostridium tyrobutyricum, carbon material balance,energy balance, carbon flow distribution, hydrogen productionSaccharolytic clostridia represent one of the largest generaof prokaryotes and satisfy the following four criteria: (a)able to form endospores; (b) must rely on the energymetabolism of obligate anaerobes; (c) unable to carry out adissimilatory sulfate reduction; and (d) the cell wall mustbe Gram-positive [2]. Clostridium tyrobutyricum, one ofthe saccharolytic clostridia, is a low-G+C Gram-positiveanaerobe and exhibits special metabolic routes to produceshort-chain fatty acids and hydrogen gas from carbohydratesand amino acids [2, 13]. Hydrogen is recognized as arenewable and promising energy alternative for the futurebecause it does not emit carbon-based gases and it hashigh specific energy content per unit mass [12]. Amongbiological hydrogen production processes, fermentativehydrogen production by clostridia proceeds from the anaerobicmetabolism of pyruvate by the following electron transferchains: pyruvate:ferredoxin oxidoreductase (PFOR), NADH:ferredoxin oxidoreductase (NFOR), and hydrogenase [23].PFOR oxidizes pyruvate to acetyl-CoA and CO
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statistical optimization of key process variables for enhanced hydrogen production by newly isolated Clostridium tyrobutyricum jm1
International Journal of Hydrogen Energy, 2008Co-Authors: Dae Sung Lee, Donghee Park, Jong Moon ParkAbstract:Abstract A fermentative hydrogen-producing bacterium was isolated from a food waste treatment process. The biological hydrogen production rate by the pure isolate (designated as Clostridium tyrobutyricum JM1) was dependent on various nutritional and environmental conditions. In this study, to enhance hydrogen production rate, the individual and mutual effects of three key process variables such as glucose concentration, pH and temperature were investigated through response surface methodology (RSM) in a batch system. A Box–Behnken design was employed to determine the effect of the three independent variables on the hydrogen production rate and to find the optimum condition of each variable for improved hydrogen production. Experimental results showed that a maximum hydrogen production rate of 5089 ml H 2 (g dry cell h) −1 was obtained under the condition of glucose concentration of 102.08 mM, temperature 35 °C and pH 6.5, and all three factors had significant influences on the specific hydrogen production rate. The RSM with the Box–Behnken design was a useful tool for achieving the high rate of hydrogen production by C. tyrobutyricum JM1.
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biological hydrogen production by immobilized cells of Clostridium tyrobutyricum jm1 isolated from a food waste treatment process
Bioresource Technology, 2008Co-Authors: Ji Hye Jo, Dae Sung Lee, Donghee Park, Jong Moon ParkAbstract:Abstract A fermentative hydrogen-producing bacterium, Clostridium tyrobutyricum JM1, was isolated from a food waste treating process using 16S rRNA gene sequencing and amplified ribosomal DNA restriction analysis (ARDRA). A fixed-bed bioreactor packed with polyurethane foam as support matrix for the growth of the isolate was operated at different hydraulic retention time (HRT) to evaluate its performance for hydrogen production. The reactor achieved the maximal hydrogen production rate of 7.2 l H 2 l −1 d −1 at 2 h HRT, where hydrogen content in biogas was 50.0%, and substrate conversion efficiency was 97.4%. The maximum hydrogen yield was 223 ml (g-hexose) −1 with an influent glucose concentration of 5 g l −1 . Therefore, the immobilized reactor using C. tyrobutyricum JM1 was an effective and stable system for continuous hydrogen production.
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The effects of pH on carbon material and energy balances in hydrogen-producing Clostridium tyrobutyricum JM1.
Bioresource Technology, 2008Co-Authors: Dae Sung Lee, Jong Moon ParkAbstract:The effects of pH on hydrogen fermentation of glucose by newly isolated H(2)-producing bacterium Clostridium tyrobutyricum JM1 were investigated in batch cultivations. The changes of carbon material and energy balances by pH conditions provided useful information for understanding and interpreting the regulatory system of the microorganism, and for optimization of a desired product, in this case, molecular hydrogen. The most probable metabolic pathways of C. tyrobutyricum JM1 were determined through an accurate analysis of stoichiometry and the consistency of the experimental data, checked by high carbon recovery. The carbon material and energy balances were adequately applied to estimate the carbon-flow distribution. They suggested that pH 6.3 was appropriate to maximize hydrogen production with a high concentration of butyrate and balanced activities of NADH.
Siqing Liu - One of the best experts on this subject based on the ideXlab platform.
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fermentative production of butyric acid from paper mill sludge hydrolysates using Clostridium tyrobutyricum nrrl b 67062 rpt 4213
Biocatalysis and agricultural biotechnology, 2018Co-Authors: Siqing Liu, Nasib Qureshi, Shona M Duncan, Joseph RichAbstract:Abstract The pulp and paper industry produces about 300–350 million tons of paper mill sludge (PMS) annually and majority is disposed of by landfill. PMS contains up to 75% carbohydrates. In this study, PMS was treated by de-ashing, fiber regeneration and enzymatic hydrolysis. The PMS hydrolysate was used for butyric acid production by Clostridium tyrobutyricum B-67062/RPT 4213. We reported that 8.52 and 8.35 gL−1 butyric acid was produced from 4 L batch fermentation in MRS and RCM4 medium respectively. Moreover, nearly 7 gL−1 butyric acid was produced by using PMS hydrolysates from two different mills when combined with a fraction of MRS, and over 6 gL−1 butyric acid was produced from hydrolysate combined with a fraction of RCM4 medium. This study suggested that beside agricultural lignocellulosic biomass feedstocks, low valued waste materials from the pulp and paper industries could also be used for the sustainable production of butyric acid.
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butyric acid from anaerobic fermentation of lignocellulosic biomass hydrolysates by Clostridium tyrobutyricum strain rpt 4213
Bioresource Technology, 2013Co-Authors: Siqing Liu, Kenneth M Bischoff, Timothy D Leathers, Nasib Qureshi, Joseph O Rich, Stephen R HughesAbstract:Abstract A novel Clostridium tyrobutyricum strain RPT-4213 was found producing butyrate under strict anaerobic conditions. This strain produced 9.47 g L−1 butyric acid from MRS media (0.48 g/g glucose). RPT-4213 was also used to ferment dilute acid pretreated hydrolysates including wheat straw (WSH), corn fiber (CFH), corn stover (CSH), rice hull (RHH), and switchgrass (SGH). Results indicated that 50% WSH with a Clostridia medium (Ct) produced the most butyric acid (8.06 g L−1, 0.46 g/g glucose), followed by 50% SGH with Ct (6.01 g L−1, 0.44 g/g glucose), however, 50% CSH Ct showed growth inhibition. RPT-4213 was then used in pH-controlled bioreactor fermentations using 60% WSH and SGH, with a dilute (0.5×) Ct medium, resulting 9.87 g L−1 butyric acid in WSH (yield 0.44 g/g) and 7.05 g L−1 butyric acid in SGH (yield 0.42 g/g). The titer and productivity could be improved through process engineering.