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Mavrommati M, Daskalaki A, Papanikolaou S, Aggelis G. Adaptive laboratory evolution principles and applications in industrial biotechnology. Biotechnol Adv 2021; 54:107795. [PMID: 34246744 DOI: 10.1016/j.biotechadv.2021.107795] [Citation(s) in RCA: 68] [Impact Index Per Article: 22.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2021] [Revised: 06/11/2021] [Accepted: 07/05/2021] [Indexed: 12/20/2022]
Abstract
Adaptive laboratory evolution (ALE) is an innovative approach for the generation of evolved microbial strains with desired characteristics, by implementing the rules of natural selection as presented in the Darwinian Theory, on the laboratory bench. New as it might be, it has already been used by several researchers for the amelioration of a variety of characteristics of widely used microorganisms in biotechnology. ALE is used as a tool for the deeper understanding of the genetic and/or metabolic pathways of evolution. Another important field targeted by ALE is the manufacturing of products of (high) added value, such as ethanol, butanol and lipids. In the current review, we discuss the basic principles and techniques of ALE, and then we focus on studies where it has been applied to bacteria, fungi and microalgae, aiming to improve their performance to biotechnological procedures and/or inspect the genetic background of evolution. We conclude that ALE is a promising and efficacious method that has already led to the acquisition of useful new microbiological strains in biotechnology and could possibly offer even more interesting results in the future.
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Affiliation(s)
- Maria Mavrommati
- Unit of Microbiology, Department of Biology, Division of Genetics, Cell Biology and Development, University of Patras, 26504 Patras, Greece; Laboratory of Food Microbiology and Biotechnology, Department of Food Science and Human Nutrition, Agricultural University of Athens, 75 Iera Odos, 11855 Athens, Greece
| | - Alexandra Daskalaki
- Unit of Microbiology, Department of Biology, Division of Genetics, Cell Biology and Development, University of Patras, 26504 Patras, Greece
| | - Seraphim Papanikolaou
- Laboratory of Food Microbiology and Biotechnology, Department of Food Science and Human Nutrition, Agricultural University of Athens, 75 Iera Odos, 11855 Athens, Greece
| | - George Aggelis
- Unit of Microbiology, Department of Biology, Division of Genetics, Cell Biology and Development, University of Patras, 26504 Patras, Greece.
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Okino N, Li M, Qu Q, Nakagawa T, Hayashi Y, Matsumoto M, Ishibashi Y, Ito M. Two bacterial glycosphingolipid synthases responsible for the synthesis of glucuronosylceramide and α-galactosylceramide. J Biol Chem 2020; 295:10709-10725. [PMID: 32518167 DOI: 10.1074/jbc.ra120.013796] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Revised: 06/02/2020] [Indexed: 12/22/2022] Open
Abstract
Bacterial glycosphingolipids such as glucuronosylceramide and galactosylceramide have been identified as ligands for invariant natural killer T cells and play important roles in host defense. However, the glycosphingolipid synthases required for production of these ceramides have not been well-characterized. Here, we report the identification and characterization of glucuronosylceramide synthase (ceramide UDP-glucuronosyltransferase [Cer-GlcAT]) in Zymomonas mobilis, a Gram-negative bacterium whose cellular membranes contain glucuronosylceramide. On comparing the gene sequences that encode the diacylglycerol GlcAT in bacteria and plants, we found a homologous gene that is widely distributed in the order Sphingomonadales in the Z. mobilis genome. We first cloned the gene and expressed it in Escherichia coli, followed by protein purification using nickel-Sepharose affinity and gel filtration chromatography. Using the highly enriched enzyme, we observed that it has high glycosyltransferase activity with UDP-glucuronic acid and ceramide as sugar donor and acceptor substrate, respectively. Cer-GlcAT deletion resulted in a loss of glucuronosylceramide and increased the levels of ceramide phosphoglycerol, which was expressed in WT cells only at very low levels. Furthermore, we found sequences homologous to Cer-GlcAT in Sphingobium yanoikuyae and Bacteroides fragilis, which have been reported to produce glucuronosylceramide and α-galactosylceramide, respectively. We expressed the two homologs of the cer-glcat gene in E. coli and found that each gene encodes Cer-GlcAT and Cer-galactosyltransferase, respectively. These results contribute to the understanding of the roles of bacterial glycosphingolipids in host-bacteria interactions and the function of bacterial glycosphingolipids in bacterial physiology.
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Affiliation(s)
- Nozomu Okino
- Department of Bioscience and Biotechnology, Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University, Nishi-ku, Fukuoka, Japan
| | - Mengbai Li
- Department of Bioscience and Biotechnology, Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University, Nishi-ku, Fukuoka, Japan
| | - Qingjun Qu
- Department of Bioscience and Biotechnology, Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University, Nishi-ku, Fukuoka, Japan
| | - Tomoko Nakagawa
- Department of Bioscience and Biotechnology, Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University, Nishi-ku, Fukuoka, Japan
| | - Yasuhiro Hayashi
- Department of Bioscience and Biotechnology, Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University, Nishi-ku, Fukuoka, Japan
| | - Mitsufumi Matsumoto
- Electric Power Development Co., Ltd., Wakamatsu Institute, Wakamatsu-ku, Kitakyushu, Fukuoka, Japan
| | - Yohei Ishibashi
- Department of Bioscience and Biotechnology, Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University, Nishi-ku, Fukuoka, Japan
| | - Makoto Ito
- Department of Bioscience and Biotechnology, Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University, Nishi-ku, Fukuoka, Japan.,Innovative Bio-architecture Center, Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University, Nishi-ku, Fukuoka, Japan
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Giri S, Shitut S, Kost C. Harnessing ecological and evolutionary principles to guide the design of microbial production consortia. Curr Opin Biotechnol 2020; 62:228-238. [DOI: 10.1016/j.copbio.2019.12.012] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Revised: 11/27/2019] [Accepted: 12/13/2019] [Indexed: 02/06/2023]
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Ajit A, Sulaiman AZ, Chisti Y. Production of bioethanol by Zymomonas mobilis in high-gravity extractive fermentations. FOOD AND BIOPRODUCTS PROCESSING 2017. [DOI: 10.1016/j.fbp.2016.12.006] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Respiratory chain analysis of Zymomonas mobilis mutants producing high levels of ethanol. Appl Environ Microbiol 2012; 78:5622-9. [PMID: 22660712 DOI: 10.1128/aem.00733-12] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We previously isolated respiratory-deficient mutant (RDM) strains of Zymomonas mobilis, which exhibited greater growth and enhanced ethanol production under aerobic conditions. These RDM strains also acquired thermotolerance. Morphologically, the cells of all RDM strains were shorter compared to the wild-type strain. We investigated the respiratory chains of these RDM strains and found that some RDM strains lost NADH dehydrogenase activity, whereas others exhibited reduced cytochrome bd-type ubiquinol oxidase or ubiquinol peroxidase activities. Complementation experiments restored the wild-type phenotype. Some RDM strains seem to have certain mutations other than the corresponding respiratory chain components. RDM strains with deficient NADH dehydrogenase activity displayed the greatest amount of aerobic growth, enhanced ethanol production, and thermotolerance. Nucleotide sequence analysis revealed that all NADH dehydrogenase-deficient strains were mutated within the ndh gene, which includes insertion, deletion, or frameshift. These results suggested that the loss of NADH dehydrogenase activity permits the acquisition of higher aerobic growth, enhanced ethanol production, and thermotolerance in this industrially important strain.
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Charoensuk K, Irie A, Lertwattanasakul N, Sootsuwan K, Thanonkeo P, Yamada M. Physiological importance of cytochrome c peroxidase in ethanologenic thermotolerant Zymomonas mobilis. J Mol Microbiol Biotechnol 2011; 20:70-82. [PMID: 21422762 DOI: 10.1159/000324675] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Zymomonas mobilis ZmCytC as a peroxidase bearing three heme c-binding motifs was investigated with ΔZmcytC constructed. The mutant exhibited filamentous shapes and reduction in growth under a shaking condition at a high temperature compared to the parental strain and became hypersensitive to exogenous H(2)O(2). Under the same condition, the mutation caused increased expression of genes for three other antioxidant enzymes. Peroxidase activity, which was detected in membrane fractions with ubiquinol-1 as a substrate but not with reduced horse heart cytochrome c, was almost abolished in ΔZmcytC. Peroxidase activity was also detected with NADH as a substrate, which was significantly inhibited by antimycin A. NADH oxidase activity of ΔZmcytC was found to be about 80% of that of the parental strain. The results suggest the involvement of ZmCytC in the aerobic respiratory chain via the cytochrome bc(1) complex in addition to the previously proposed direct interaction with ubiquinol and its contribution to protection against oxidative stress.
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Affiliation(s)
- Kannikar Charoensuk
- Applied Molecular Bioscience, Graduate School of Medicine, Yamaguchi University, Ube, Japan
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Lee KY, Park JM, Kim TY, Yun H, Lee SY. The genome-scale metabolic network analysis of Zymomonas mobilis ZM4 explains physiological features and suggests ethanol and succinic acid production strategies. Microb Cell Fact 2010; 9:94. [PMID: 21092328 PMCID: PMC3004842 DOI: 10.1186/1475-2859-9-94] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2010] [Accepted: 11/24/2010] [Indexed: 01/04/2023] Open
Abstract
Background Zymomonas mobilis ZM4 is a Gram-negative bacterium that can efficiently produce ethanol from various carbon substrates, including glucose, fructose, and sucrose, via the Entner-Doudoroff pathway. However, systems metabolic engineering is required to further enhance its metabolic performance for industrial application. As an important step towards this goal, the genome-scale metabolic model of Z. mobilis is required to systematically analyze in silico the metabolic characteristics of this bacterium under a wide range of genotypic and environmental conditions. Results The genome-scale metabolic model of Z. mobilis ZM4, ZmoMBEL601, was reconstructed based on its annotated genes, literature, physiological and biochemical databases. The metabolic model comprises 579 metabolites and 601 metabolic reactions (571 biochemical conversion and 30 transport reactions), built upon extensive search of existing knowledge. Physiological features of Z. mobilis were then examined using constraints-based flux analysis in detail as follows. First, the physiological changes of Z. mobilis as it shifts from anaerobic to aerobic environments (i.e. aerobic shift) were investigated. Then the intensities of flux-sum, which is the cluster of either all ingoing or outgoing fluxes through a metabolite, and the maximum in silico yields of ethanol for Z. mobilis and Escherichia coli were compared and analyzed. Furthermore, the substrate utilization range of Z. mobilis was expanded to include pentose sugar metabolism by introducing metabolic pathways to allow Z. mobilis to utilize pentose sugars. Finally, double gene knock-out simulations were performed to design a strategy for efficiently producing succinic acid as another example of application of the genome-scale metabolic model of Z. mobilis. Conclusion The genome-scale metabolic model reconstructed in this study was able to successfully represent the metabolic characteristics of Z. mobilis under various conditions as validated by experiments and literature information. This reconstructed metabolic model will allow better understanding of Z. mobilis metabolism and consequently designing metabolic engineering strategies for various biotechnological applications.
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Affiliation(s)
- Kyung Yun Lee
- Metabolic and Biomolecular Engineering National Research Laboratory, Department of Chemical and Biomolecular Engineering (BK21 program), KAIST, 335 Gwahangno, Yuseong-gu, Daejeon 305-701, Republic of Korea
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Zhang L, Lang Y, Wang C, Nagata S. Promoting effect of compatible solute ectoine on the ethanol fermentation by Zymomonas mobilis CICC10232. Process Biochem 2008. [DOI: 10.1016/j.procbio.2008.02.003] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Abstract
The ethanol-producing bacterium Zymomonas mobilis can serve as a model organism for the study of rapid catabolism and inefficient energy conversion in bacteria. Some basic aspects of its physiology still remain poorly understood. Here, the energy-spilling pathways during uncoupled growth, the structure and function of electron transport chain, and the possible reasons for the inefficient oxidative phosphorylation are analysed. Also, the interaction between ethanol synthesis and respiration is considered. The search for mechanisms of futile transmembrane proton cycling, as well as identification of respiratory electron transport complexes, like the energy-coupling NAD(P)H:quinone oxidoreductase and the cyanide-sensitive terminal oxidase(s), are outlined as the key problems for further research of Z. mobilis energy metabolism.
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Affiliation(s)
- Uldis Kalnenieks
- Institute of Microbiology and Biotechnology, Chair of Microbiology and Biotechnology, University of Latvia, Kronvalda boulv. 4, Riga, LV-1586, Latvia
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Abstract
A personal computer-based on-line monitoring and controlling system was developed for the fermentation of microorganism. The on-line HPLC system for the analysis of glucose and ethanol in the fermentation broth was connected to the fermenter via an auto-sampling equipment, which could perform the pipetting, filtration and dilution of the sample and final injection onto the HPLC through automation based on a programmed procedure. The A/D and D/A interfaces were equipped in order to process the signals from electrodes and from the detector of HPLC, and to direct the feed pumps, the motor of stirrer and gas flow-rate controller. The software that supervised the control of the stirring speed, gas flow-rate, pH value, feed flow-rate of medium, and the on-line measurement of glucose and ethanol concentration was programmed by using Microsoft Visual Basic under Microsoft Windows. The signal for chromatographic peaks from on-line HPLC was well captured and processed using an RC filter and a smoothing algorithm. This monitoring and control system was demonstrated to be effective in the ethanol fermentation of Zymomonas mobilis operated in both batch and fed-batch modes. In addition to substrate and product concentrations determined by on-line HPLC, the biomass concentration in Z. mobilis fermentation could also be on-line estimated by using the pH control and an implemented software sensor. The substrate concentration profile in the fed-back fermentation followed well the set point profile due to the fed-back action of feed flow-rate control.
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Kannan T, Sangiliyandi G, Gunasekaran P. Improved ethanol production from sucrose by a mutant of Zymomonas mobilis lacking sucrases in immobilized cell fermentation. Enzyme Microb Technol 1998. [DOI: 10.1016/s0141-0229(97)00158-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Improved technique for the isolation of stable mutants ofZymomonas mobilis. Folia Microbiol (Praha) 1997. [DOI: 10.1007/bf02815465] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Identification of inhibitory components toxic toward zymomonas mobilis CP4(pZB5) xylose fermentation. Appl Biochem Biotechnol 1997. [DOI: 10.1007/bf02788797] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Lawford HG, Rousseau JD. Corn steep liquor as a cost-effective nutrition adjunct in high-performanceZymomonas ethanol fermentations. Appl Biochem Biotechnol 1997; 63-65:287-304. [DOI: 10.1007/bf02920431] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Ait-Abdelkader N, Pencreach G, Joset F, Baratti JC. Isolation and Properties of Mutants of Zymomonas mobilis Deficient in Sugar Assimilation. Appl Environ Microbiol 1996; 62:1096-8. [PMID: 16535260 PMCID: PMC1388817 DOI: 10.1128/aem.62.3.1096-1098.1996] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
An enrichment method using d-cycloserine was designed for the isolation of spontaneous mutants of Zymomonas mobilis deficient in glucose or fructose utilization. The mutants could easily be isolated since they represented 80 to 90% of the population after two and three enrichment cycles. Glucokinase and fructokinase activities in the mutants were affected.
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Kannan R, Pitchaimani K, Gunasekaran P, Aït-abdelkader N, Baratti J. Overexpression of extracellular sucrase (SacC) of Zymomonas mobilisin Escherichia coli. FEMS Microbiol Lett 1995. [DOI: 10.1111/j.1574-6968.1995.tb07857.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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O'Mullan PJ, Buchholz SE, Chase T, Eveleigh DE. Roles of alcohol dehydrogenases of Zymomonas mobilis (ZADH): characterization of a ZADH-2-negative mutant. Appl Microbiol Biotechnol 1995. [DOI: 10.1007/bf00164772] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Kim YJ, Song KB, Rhee SK. A novel aerobic respiratory chain-linked NADH oxidase system in Zymomonas mobilis. J Bacteriol 1995; 177:5176-8. [PMID: 7665502 PMCID: PMC177303 DOI: 10.1128/jb.177.17.5176-5178.1995] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Membrane vesicles prepared from Zymomonas mobilis oxidized NADH exclusively, whereas deamino-NADH was little oxidized. In addition, the respiratory chain-linked NADH oxidase system exhibited only a single apparent Km value of approximately 66 microM for NADH. The NADH oxidase was highly sensitive to the respiratory chain inhibitor 2-heptyl-4-hydroxyquinoline-N-oxide. However, the NADH:quinone oxidoreductase was not sensitive to 2-heptyl-4-hydroxyquinoline-N-oxide and was highly resistant to another respiratory chain inhibitor, rotenone. Electron transfer from NADH to oxygen generated a proton electrochemical gradient (inside positive) in inside-out membrane vesicles. In contrast, electron transfer from NADH to ubiquinone-1 generated no electrochemical gradient. These findings indicate that Z. mobilis possesses only NADH:quinone oxidoreductase lacking the energy coupling site.
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Affiliation(s)
- Y J Kim
- Department of Microbiology, Changwon National University, Kyungnam, Republic of Korea
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The sacB and sacC genes encoding levansucrase and sucrase form a gene cluster in Zymomonas mobilis. Biotechnol Lett 1995. [DOI: 10.1007/bf00129392] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Kannan R, Mukundan G, Aït-Abdelkader N, Augier-Magro V, Baratti J, Gunasekaran P. Molecular cloning and characterization of the extracellular sucrase gene (sacC) of Zymomonas mobilis. Arch Microbiol 1995; 163:195-204. [PMID: 7778976 DOI: 10.1007/bf00305353] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The Zymomonas mobilis gene sacC that encodes the extracellular sucrase (protein B46) was cloned and expressed in Escherichia coli. The gene was found to be present downstream to the already described levansucrase gene sacB in the cloned chromosomal fragment of Z. mobilis. The expression product was different from SacB and exhibited sucrase but not levansucrase activity; therefore, SacC behaves like a true sucrase. Expression of sacC in E. coli JM109 and XL1 was very low; overexpression was observed in E. coli BL21 after induction of the T7 polymerase expression system with IPTG. Subcellular fractionation of the E. coli clone carrying plasmid pLSS2811 showed that more than 70% of the sucrase activity could be detected in the cytoplasmic fraction, suggesting that the enzyme was soluble and not secreted in E. coli. The nucleotide sequence analysis of sacC revealed an open reading frame 1239bp long coding for a 413 amino acid protein with a molecular mass of 46 kDa. The first 30 deduced amino acids from this ORF were identical with those from the N-terminal sequence of the extracellular sucrase (protein B46) purified from Z. mobilis ZM4. No leader peptide sequence could be identified in the sacC gene. The amino acid sequence of SacC showed very little similarity to those of other known sucrases, but was very similar to the levansucrases of Z. mobilis (61.5%), Erwinia amylovora (40.2%) and Bacillus subtilis (25.6%).
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Affiliation(s)
- R Kannan
- Department of Microbial Technology, School of Biological Sciences, Madurai Kamaraj University, India
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Lawford HG, Rousseau JD. Effect of oxygen on ethanol production by a recombinant ethanologenic E. coli. Appl Biochem Biotechnol 1994; 45-46:349-66. [PMID: 8010765 DOI: 10.1007/bf02941811] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Escherichia coli strain B, bearing the pet plasmid pLO1297, and the wild-type culture, lacking the plasmid, responded to aeration of the complex medium by an approximate three- and fourfold increase in both growth rate and growth yield with glucose and xylose, respectively. At a relatively low oxygen transfer rate (8 mmol O2/L/h), the sugar-to-ethanol conversion efficiency exhibited by the recombinant strain decreased 40% and 30% for glucose and xylose, respectively. At a high aeration efficiency (100 mmol O2/L/h), the ethanol yield with respect to xylose was 0.15 g/g for the recombinant and 0.25 g/g for the culture lacking the plasmid. These observations suggest that oxygen reduces the ethanologenic efficiency of recombinant E. coli by diverting carbon to growth and end products other than ethanol. Previous observations, by others, on the effect of oxygen on ethanologenic recombinant E. coli were made with different strains bearing different plasmids. In addition to the possibility of strain and plasmid specificity, the results of this study suggest that previous conclusions were influenced by the particular environmental conditions imposed on the culture, including poor aeration efficiency and lack of pH control.
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Affiliation(s)
- H G Lawford
- Department of Biochemistry, University of Toronto, Ontario, Canada
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Castellar M, Cánovas FM, Iborra J. Optimization of the start-up of a passively immobilized Zymomonas mobilis system for continuous ethanol production. Process Biochem 1994. [DOI: 10.1016/0032-9592(94)80020-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Park SC, Kademi A, Baratti JC. Alcoholic fermentation of cellulose hydrolysate by Zymomonas mobilis. Biotechnol Lett 1993. [DOI: 10.1007/bf00131212] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Lawford HG, Rousseau JD. The effect of acetic acid on fuel ethanol production byZymomonas. Appl Biochem Biotechnol 1993. [DOI: 10.1007/bf02919028] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Lawford HG, Rousseau JD. A comparative study of glucose conversion to ethanol by Zymomonas mobilis and a recombinant Escherichia coli. Biotechnol Lett 1993. [DOI: 10.1007/bf00129326] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Doelle HW, Kirk L, Crittenden R, Toh H, Doelle MB. Zymomonas mobilis--science and industrial application. Crit Rev Biotechnol 1993; 13:57-98. [PMID: 8477453 DOI: 10.3109/07388559309069198] [Citation(s) in RCA: 107] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Zymomonas mobilis is undoubtedly one of the most unique bacterium within the microbial world. Known since 1912 under the names Termobacterium mobilis, Pseudomonas linderi, and Zymomonas mobilis, reviews on its uniqueness have been published in 1977 and 1988. The bacterium Zymomonas mobilis not only exhibits an extraordinarily uniqueness in its biochemistry, but also in its growth behavior, energy production, and response to culture conditions, as well as cultivation techniques used. This uniqueness caused great interest in the scientific, biotechnological, and industrial worlds. Its ability to couple and uncouple energy production in favor of product formation, to respond to physical and chemical environment manipulation, as well as its restricted product formation, makes it an ideal microorganism for microbial process development. This review explores the advances made since 1987, together with new developments in the pure scientific and applied commercial areas.
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Affiliation(s)
- H W Doelle
- Department of Microbiology, University of Queensland, Brisbane, Australia
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Park SC, Baratti JC. Continuous ethanol production from sugar beet molasses using an osmotolerant mutant strain of Zymomonas mobilis. ACTA ACUST UNITED AC 1992. [DOI: 10.1016/0922-338x(92)90224-i] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Park SC, Baratti J. Batch fermentation kinetics of sugar beet molasses byZymomonas mobilis. Biotechnol Bioeng 1991; 38:304-13. [DOI: 10.1002/bit.260380312] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Park SC, Baratti J. Comparison of ethanol production by Zymomonas mobilis from sugar beet substrates. Appl Microbiol Biotechnol 1991; 35:283-291. [DOI: 10.1007/bf00172713] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/1991] [Accepted: 03/07/1991] [Indexed: 11/24/2022]
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Oaxaca VA, Jones LP. Formation of ethanol and higher alcohols by immobilized zymomonas mobilis in continuous culture. ACTA ACUST UNITED AC 1991. [DOI: 10.1002/abio.370110602] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Gunasekaran P, Karunakaran T, Cami B, Mukundan AG, Preziosi L, Baratti J. Cloning and sequencing of the sacA gene: characterization of a sucrase from Zymomonas mobilis. J Bacteriol 1990; 172:6727-35. [PMID: 2254250 PMCID: PMC210786 DOI: 10.1128/jb.172.12.6727-6735.1990] [Citation(s) in RCA: 59] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The Zymomonas mobilis gene (sacA) encoding a protein with sucrase activity has been cloned in Escherichia coli and its nucleotide sequence has been determined. Potential ribosome-binding site and promoter sequences were identified in the region upstream of the gene which were homologous to E. coli and Z. mobilis consensus sequences. Extracts from E. coli cells, containing the sacA gene, displayed a sucrose-hydrolyzing activity. However, no transfructosylation activity (exchange reaction or levan formation) could be detected. This sucrase activity was different from that observed with the purified extracellular protein B46 from Z. mobilis. These two proteins showed different electrophoretic mobilities and molecular masses and shared no immunological similarity. Thus, the product of sacA (a polypeptide of 58.4-kDa molecular mass) is a new sucrase from Z. mobilis. The amino acid sequence, deduced from the nucleotide sequence of sacA, showed strong homologies with the sucrases from Bacillus subtilis, Salmonella typhimurium, and Vibrio alginolyticus.
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Affiliation(s)
- P Gunasekaran
- Laboratoire de Chimie Bactérienne, Centre National de la Recherche Scientifique, Marseille, France
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Identification of microbial isolates by DNA fingerprinting: analysis of ATCC Zymomonas strains. J Biotechnol 1990. [DOI: 10.1016/0168-1656(90)90081-l] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Abstract
The bacterium Zymomonas mobilis is a potentially useful organism for the commercial production of ethanol as it is capable of more than double the rate of alcohol production by yeast. However, industrial application of this bacterium has been restricted in part due to the disadvantages of its limited substrate range (glucose, fructose and sucrose) and by-product formation. Progress in strain improvement and genetic manipulation of this ethanologen is reviewed. Methodologies for gaining reproducible gene transfer in Z. mobilis have recently been developed. Genetic modification has led to its growth on the additional substrates lactose and mannitol. Additionally, a range of by-product negative mutants have also been isolated. Further interest has focused on transfer of Z. mobilis genes to other fermentive organisms in order to gain enhanced product formation. Overall, these genetic approaches should lead to development of novel strains of Z. mobilis and other genera, capable of the use of starch, cellulose and xylan in a manner attractive for industrial ethanol production, besides facilitating over production of products from E. coli strains with enhanced capability to grow at high density.
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Affiliation(s)
- S E Buchholz
- Bioprocess Development Department, Hoffman-La Roche, Inc., Nutley, NJ 07110, USA
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Castellar MR, Borrego F, C�novas M, Manj�n A, Iborra JL. Stability against stop of flow of an immobilizedZymomonas mobilis bioreactor. Biotechnol Lett 1989. [DOI: 10.1007/bf01025279] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Buchholz SE, Eveleigh DE. Effect of dilution buffers on cell viability of Zymomonas mobilis. J Microbiol Methods 1989. [DOI: 10.1016/0167-7012(89)90002-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Borrego F, Ob�n JM, C�novas M, Manj�n A, Iborra JL. pH influence on ethanol production and retained biomass in a passively immobilizedZymomonas mobilis system. Biotechnol Lett 1988. [DOI: 10.1007/bf01087446] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Bringer-Meyer S, Sahm H. Metabolic shifts inZymomonas mobilisin response to growth conditions. FEMS Microbiol Lett 1988. [DOI: 10.1111/j.1574-6968.1988.tb02739.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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Borrego F, Ob�n JM, C�novas M, Manj�n A, Iborra JL. Effect of temperature and long-term operation on passively immobilizedZymomonas mobilis for continuous ethanol production. Biotechnol Lett 1987. [DOI: 10.1007/bf01026663] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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