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Espinosa MI, Williams TC, Pretorius IS, Paulsen IT. Benchmarking two Saccharomyces cerevisiae laboratory strains for growth and transcriptional response to methanol. Synth Syst Biotechnol 2019; 4:180-188. [PMID: 31667368 PMCID: PMC6807065 DOI: 10.1016/j.synbio.2019.10.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2019] [Revised: 09/27/2019] [Accepted: 10/03/2019] [Indexed: 11/21/2022] Open
Abstract
One-carbon compounds, such as methanol, are becoming potential alternatives to sugars as feedstocks for the biological production of chemicals, fuels, foods, and pharmaceuticals. Efficient biological production often requires extensive genetic manipulation of a microbial host strain, making well-characterised and genetically-tractable model organisms like the yeast Saccharomyces cerevisiae attractive targets for the engineering of methylotrophic metabolism. S. cerevisiae strains S288C and CEN.PK are the two best-characterised and most widely used hosts for yeast synthetic biology and metabolic engineering, yet they have unpredictable metabolic phenotypes related to their many genomic differences. We therefore sought to benchmark these two strains as potential hosts for engineered methylotrophic metabolism by comparing their growth and transcriptomic responses to methanol. CEN.PK had improved growth in the presence of methanol relative to the S288C derivative BY4741. The CEN.PK transcriptome also had a specific and relevant response to methanol that was either absent or less pronounced in the BY4741 strain. This response included up-regulation of genes associated with mitochondrial and peroxisomal metabolism, alcohol and formate dehydrogenation, glutathione metabolism, and the global transcriptional regulator of metabolism MIG3. Over-expression of MIG3 enabled improved growth in the presence of methanol, suggesting that MIG3 is a mediator of the superior CEN.PK strain growth. CEN.PK was therefore identified as a superior strain for the future development of synthetic methylotrophy in S. cerevisiae.
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Affiliation(s)
- Monica I. Espinosa
- ARC Centre of Excellence in Synthetic Biology, Department of Molecular Sciences, Macquarie University, NSW, Australia
- CSIRO Synthetic Biology Future Science Platform, Canberra, ACT, 2601, Australia
| | - Thomas C. Williams
- ARC Centre of Excellence in Synthetic Biology, Department of Molecular Sciences, Macquarie University, NSW, Australia
- CSIRO Synthetic Biology Future Science Platform, Canberra, ACT, 2601, Australia
| | - Isak S. Pretorius
- ARC Centre of Excellence in Synthetic Biology, Department of Molecular Sciences, Macquarie University, NSW, Australia
| | - Ian T. Paulsen
- ARC Centre of Excellence in Synthetic Biology, Department of Molecular Sciences, Macquarie University, NSW, Australia
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2
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Mixed carbon substrates: a necessary nuisance or a missed opportunity? Curr Opin Biotechnol 2019; 62:15-21. [PMID: 31513988 DOI: 10.1016/j.copbio.2019.07.003] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2019] [Revised: 06/24/2019] [Accepted: 07/03/2019] [Indexed: 11/20/2022]
Abstract
Although fermentation with single carbon sources is the preferred mode of operation in current industrial biotechnology, the use of multiple substrates has been continuously investigated throughout the years. Generally, microbial metabolism varies significantly when cells are presented with mixed carbon substrates compared to a single carbon-energy source, as different nutrients interact in complex ways within the metabolic network. By exploiting these distinct modes of interaction, researchers have identified unique opportunities to optimize metabolism using mixed carbon sources. Here we review situations where process yield and productivity are markedly improved through the judicious introduction of substrate mixtures. Our goal is to illustrate that with proper design of the choice of substrates and the way they are introduced to cultures, metabolic optimization with mixed substrates can be a unique strategy that complements genetic engineering techniques to enhance cell performance beyond what is accomplished in single substrate fermentations.
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3
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Evaluation of a novel cloud-based software platform for structured experiment design and linked data analytics. Sci Data 2018; 5:180195. [PMID: 30280721 PMCID: PMC6169258 DOI: 10.1038/sdata.2018.195] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Accepted: 08/08/2018] [Indexed: 11/30/2022] Open
Abstract
Open data in science requires precise definition of experimental procedures used in data generation, but traditional practices for sharing protocols and data cannot provide the required data contextualization. Here, we explore implementation, in an academic research setting, of a novel cloud-based software system designed to address this challenge. The software supports systematic definition of experimental procedures as visual processes, acquisition and analysis of primary data, and linking of data and procedures in machine-computable form. The software was tested on a set of quantitative microbial-physiology experiments. Though time-intensive, definition of experimental procedures in the software enabled much more precise, unambiguous definitions of experiments than conventional protocols. Once defined, processes were easily reusable and composable into more complex experimental flows. Automatic coupling of process definitions to experimental data enables immediate identification of correlations between procedural details, intended and unintended experimental perturbations, and experimental outcomes. Software-based experiment descriptions could ultimately replace terse and ambiguous ‘Materials and Methods’ sections in scientific journals, thus promoting reproducibility and reusability of published studies.
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Dai Z, Gu H, Zhang S, Xin F, Zhang W, Dong W, Ma J, Jia H, Jiang M. Metabolic construction strategies for direct methanol utilization in Saccharomyces cerevisiae. BIORESOURCE TECHNOLOGY 2017; 245:1407-1412. [PMID: 28554521 DOI: 10.1016/j.biortech.2017.05.100] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Revised: 05/15/2017] [Accepted: 05/16/2017] [Indexed: 06/07/2023]
Abstract
The aim of this study was to metabolically construct Saccharomyces cerevisiae for achievement of direct methanol utilization and value added product (mainly pyruvate) production. After successful integration of methanol oxidation pathway originated from Pichia pastoris into the chromosome of S. cerevisiae, the recombinant showed 1.04g/L consumption of methanol and 3.13% increase of cell growth (OD600) when using methanol as the sole carbon source. Moreover, 0.26g/L of pyruvate was detected in the fermentation broth. The supplementation of 1g/L yeast extract could further improve cell growth with increase of 11.70% and methanol consumption to 2.35g/L. This represents the first genetically modified non-methylotrophic eukaryotic microbe for direct methanol utilization and would be of great value concerning the development of biotechnological processes.
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Affiliation(s)
- Zhongxue Dai
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211800, PR China.
| | - Honglian Gu
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211800, PR China.
| | - Shangjie Zhang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211800, PR China.
| | - Fengxue Xin
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211800, PR China.
| | - Wenming Zhang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211800, PR China; Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University, Nanjing 211800, PR China.
| | - Weiliang Dong
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211800, PR China.
| | - Jiangfeng Ma
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211800, PR China.
| | - Honghua Jia
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211800, PR China; Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University, Nanjing 211800, PR China.
| | - Min Jiang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211800, PR China; Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University, Nanjing 211800, PR China.
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5
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Geier M, Brandner C, Strohmeier GA, Hall M, Hartner FS, Glieder A. Engineering Pichia pastoris for improved NADH regeneration: A novel chassis strain for whole-cell catalysis. Beilstein J Org Chem 2015; 11:1741-8. [PMID: 26664594 PMCID: PMC4660914 DOI: 10.3762/bjoc.11.190] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2015] [Accepted: 08/26/2015] [Indexed: 11/30/2022] Open
Abstract
Many synthetically useful reactions are catalyzed by cofactor-dependent enzymes. As cofactors represent a major cost factor, methods for efficient cofactor regeneration are required especially for large-scale synthetic applications. In order to generate a novel and efficient host chassis for bioreductions, we engineered the methanol utilization pathway of Pichia pastoris for improved NADH regeneration. By deleting the genes coding for dihydroxyacetone synthase isoform 1 and 2 (DAS1 and DAS2), NADH regeneration via methanol oxidation (dissimilation) was increased significantly. The resulting Δdas1 Δdas2 strain performed better in butanediol dehydrogenase (BDH1) based whole-cell conversions. While the BDH1 catalyzed acetoin reduction stopped after 2 h reaching ~50% substrate conversion when performed in the wild type strain, full conversion after 6 h was obtained by employing the knock-out strain. These results suggest that the P. pastoris Δdas1 Δdas2 strain is capable of supplying the actual biocatalyst with the cofactor over a longer reaction period without the over-expression of an additional cofactor regeneration system. Thus, focusing the intrinsic carbon flux of this methylotrophic yeast on methanol oxidation to CO2 represents an efficient and easy-to-use strategy for NADH-dependent whole-cell conversions. At the same time methanol serves as co-solvent, inductor for catalyst and cofactor regeneration pathway expression and source of energy.
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Affiliation(s)
- Martina Geier
- Austrian Centre of Industrial Biotechnology (ACIB GmbH), Petersgasse 14, Graz, 8010, Austria
| | - Christoph Brandner
- Austrian Centre of Industrial Biotechnology (ACIB GmbH), Petersgasse 14, Graz, 8010, Austria
| | - Gernot A Strohmeier
- Austrian Centre of Industrial Biotechnology (ACIB GmbH), Petersgasse 14, Graz, 8010, Austria ; Institute of Organic Chemistry, Graz University of Technology, Stremayrgasse 9, Graz, 8010, Austria
| | - Mélanie Hall
- Department of Chemistry, University of Graz, Heinrichstrasse 28, Graz, 8010, Austria
| | - Franz S Hartner
- Sandoz GmbH, Biochemiestrasse 10, 6250, Kundl, Austria ; Institute of Molecular Biotechnology, Graz University of Technology, Petersgasse 14, Graz, 8010, Austria
| | - Anton Glieder
- Institute of Molecular Biotechnology, Graz University of Technology, Petersgasse 14, Graz, 8010, Austria
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Metabolic engineering of Corynebacterium glutamicum for methanol metabolism. Appl Environ Microbiol 2015; 81:2215-25. [PMID: 25595770 DOI: 10.1128/aem.03110-14] [Citation(s) in RCA: 78] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Methanol is already an important carbon feedstock in the chemical industry, but it has found only limited application in biotechnological production processes. This can be mostly attributed to the inability of most microbial platform organisms to utilize methanol as a carbon and energy source. With the aim to turn methanol into a suitable feedstock for microbial production processes, we engineered the industrially important but nonmethylotrophic bacterium Corynebacterium glutamicum toward the utilization of methanol as an auxiliary carbon source in a sugar-based medium. Initial oxidation of methanol to formaldehyde was achieved by heterologous expression of a methanol dehydrogenase from Bacillus methanolicus, whereas assimilation of formaldehyde was realized by implementing the two key enzymes of the ribulose monophosphate pathway of Bacillus subtilis: 3-hexulose-6-phosphate synthase and 6-phospho-3-hexuloisomerase. The recombinant C. glutamicum strain showed an average methanol consumption rate of 1.7 ± 0.3 mM/h (mean ± standard deviation) in a glucose-methanol medium, and the culture grew to a higher cell density than in medium without methanol. In addition, [(13)C]methanol-labeling experiments revealed labeling fractions of 3 to 10% in the m + 1 mass isotopomers of various intracellular metabolites. In the background of a C. glutamicum Δald ΔadhE mutant being strongly impaired in its ability to oxidize formaldehyde to CO2, the m + 1 labeling of these intermediates was increased (8 to 25%), pointing toward higher formaldehyde assimilation capabilities of this strain. The engineered C. glutamicum strains represent a promising starting point for the development of sugar-based biotechnological production processes using methanol as an auxiliary substrate.
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Oka T, Komachi Y, Ohshima K, Kawano Y, Fukuda K, Nagahama K, Ekino K, Nomura Y. Isolation, sequencing, and heterologous expression of the Paecilomyces variotii gene encoding S-hydroxymethylglutathione dehydrogenase (fldA). Appl Microbiol Biotechnol 2014; 99:1755-63. [PMID: 25398285 PMCID: PMC4322224 DOI: 10.1007/s00253-014-6203-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2014] [Revised: 10/29/2014] [Accepted: 10/30/2014] [Indexed: 11/25/2022]
Abstract
The filamentous fungus Paecilomyces variotii NBRC 109023 (teleomorph: Byssochlamys spectabilis NBRC 109023) degrades formaldehyde at concentrations as high as 2.4 % (w/v). In many prokaryotes and in all known eukaryotes, formaldehyde degradation is catalyzed by S-hydroxymethylglutathione (S-HMGSH) dehydrogenase. We report here the isolation and characterization of the gene encoding S-HMGSH dehydrogenase activity in P. variotii. The 1.6-kb fldA gene contained 5 introns and 6 exons, and the corresponding cDNA was 1143 bp, encoding a 40-kDa protein composed of 380 amino acids. FldA was predicted to have 74.3, 73.7, 68.5, and 67.4 % amino acid identity to the S-HMGSH dehydrogenases of Hansenula polymorpha, Candida boidinii, Saccharomyces cerevisiae, and Kluyveromyces lactis, respectively. The predicted protein also showed high amino acid similarity (84∼86 %) to the products of putative fldA genes from other filamentous fungi, including Aspergillus sp. and Penicillium sp. Notably, the P. variotii fldA gene was able to functionally complement a Saccharomyces cerevisiae strain (BY4741 ∆sfa1) lacking the gene for S-HMGSH dehydrogenase. The heterologous expression construct rendered BY4741 ∆sfa1 tolerant to exogenous formaldehyde. Although BY4741 (parental wild-type strain) was unable to degrade even low concentrations of formaldehyde, BY4741 ∆sfa1 harboring Paecilomyces fldA was able to degrade 4 mM formaldehyde within 30 h. The findings from this study confirm the essential role of S-HMGSH dehydrogenase in detoxifying formaldehyde.
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Affiliation(s)
- Takuji Oka
- Department of Applied Microbial Technology, Faculty of Biotechnology and Life Science, Sojo University, Ikeda 4-22-1, Kumamoto, 860-0082 Japan
| | - Yuji Komachi
- Department of Applied Microbial Technology, Faculty of Biotechnology and Life Science, Sojo University, Ikeda 4-22-1, Kumamoto, 860-0082 Japan
| | - Kazufumi Ohshima
- Department of Applied Microbial Technology, Faculty of Biotechnology and Life Science, Sojo University, Ikeda 4-22-1, Kumamoto, 860-0082 Japan
| | - Yoichi Kawano
- Department of Applied Microbial Technology, Faculty of Biotechnology and Life Science, Sojo University, Ikeda 4-22-1, Kumamoto, 860-0082 Japan
| | - Kohsai Fukuda
- Department of Applied Microbial Technology, Faculty of Biotechnology and Life Science, Sojo University, Ikeda 4-22-1, Kumamoto, 860-0082 Japan
| | - Kazuhiro Nagahama
- Department of Applied Microbial Technology, Faculty of Biotechnology and Life Science, Sojo University, Ikeda 4-22-1, Kumamoto, 860-0082 Japan
| | - Keisuke Ekino
- Department of Applied Microbial Technology, Faculty of Biotechnology and Life Science, Sojo University, Ikeda 4-22-1, Kumamoto, 860-0082 Japan
| | - Yoshiyuki Nomura
- Department of Applied Microbial Technology, Faculty of Biotechnology and Life Science, Sojo University, Ikeda 4-22-1, Kumamoto, 860-0082 Japan
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Ravin NV, Eldarov MA, Kadnikov VV, Beletsky AV, Schneider J, Mardanova ES, Smekalova EM, Zvereva MI, Dontsova OA, Mardanov AV, Skryabin KG. Genome sequence and analysis of methylotrophic yeast Hansenula polymorpha DL1. BMC Genomics 2013; 14:837. [PMID: 24279325 PMCID: PMC3866509 DOI: 10.1186/1471-2164-14-837] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2013] [Accepted: 11/15/2013] [Indexed: 12/04/2022] Open
Abstract
BACKGROUND Hansenula polymorpha DL1 is a methylotrophic yeast, widely used in fundamental studies of methanol metabolism, peroxisome biogenesis and function, and also as a microbial cell factory for production of recombinant proteins and metabolic engineering towards the goal of high temperature ethanol production. RESULTS We have sequenced the 9 Mbp H. polymorpha DL1 genome and performed whole-genome analysis for the H. polymorpha transcriptome obtained from both methanol- and glucose-grown cells. RNA-seq analysis revealed the complex and dynamic character of the H. polymorpha transcriptome under the two studied conditions, identified abundant and highly unregulated expression of 40% of the genome in methanol grown cells, and revealed alternative splicing events. We have identified subtelomerically biased protein families in H. polymorpha, clusters of LTR elements at G + C-poor chromosomal loci in the middle of each of the seven H. polymorpha chromosomes, and established the evolutionary position of H. polymorpha DL1 within a separate yeast clade together with the methylotrophic yeast Pichia pastoris and the non-methylotrophic yeast Dekkera bruxellensis. Intergenome comparisons uncovered extensive gene order reshuffling between the three yeast genomes. Phylogenetic analyses enabled us to reveal patterns of evolution of methylotrophy in yeasts and filamentous fungi. CONCLUSIONS Our results open new opportunities for in-depth understanding of many aspects of H. polymorpha life cycle, physiology and metabolism as well as genome evolution in methylotrophic yeasts and may lead to novel improvements toward the application of H. polymorpha DL-1 as a microbial cell factory.
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Affiliation(s)
- Nikolai V Ravin
- Centre “Bioengineering” of RAS, Prosp. 60-let Oktyabrya, bld. 7-1, Moscow 117312, Russia
| | - Michael A Eldarov
- Centre “Bioengineering” of RAS, Prosp. 60-let Oktyabrya, bld. 7-1, Moscow 117312, Russia
| | - Vitaly V Kadnikov
- Centre “Bioengineering” of RAS, Prosp. 60-let Oktyabrya, bld. 7-1, Moscow 117312, Russia
| | - Alexey V Beletsky
- Centre “Bioengineering” of RAS, Prosp. 60-let Oktyabrya, bld. 7-1, Moscow 117312, Russia
| | - Jessica Schneider
- Institute for Bioinformatics, Center for Biotechnology, Bielefeld University, Universitätsstraße 25, 33615 Bielefeld, Germany
| | - Eugenia S Mardanova
- Centre “Bioengineering” of RAS, Prosp. 60-let Oktyabrya, bld. 7-1, Moscow 117312, Russia
| | - Elena M Smekalova
- Faculty of Chemistry, Lomonosov Moscow State University, 119999 Moscow, Russia and Belozersky Institute, Moscow State University, Leninskie Gory 1, Bldg. 40, 119991 Moscow, Russia
| | - Maria I Zvereva
- Faculty of Chemistry, Lomonosov Moscow State University, 119999 Moscow, Russia and Belozersky Institute, Moscow State University, Leninskie Gory 1, Bldg. 40, 119991 Moscow, Russia
| | - Olga A Dontsova
- Faculty of Chemistry, Lomonosov Moscow State University, 119999 Moscow, Russia and Belozersky Institute, Moscow State University, Leninskie Gory 1, Bldg. 40, 119991 Moscow, Russia
| | - Andrey V Mardanov
- Centre “Bioengineering” of RAS, Prosp. 60-let Oktyabrya, bld. 7-1, Moscow 117312, Russia
| | - Konstantin G Skryabin
- Centre “Bioengineering” of RAS, Prosp. 60-let Oktyabrya, bld. 7-1, Moscow 117312, Russia
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Kaszycki P, Walski T, Hachicho N, Heipieper HJ. Biostimulation by methanol enables the methylotrophic yeasts Hansenula polymorpha and Trichosporon sp. to reveal high formaldehyde biodegradation potential as well as to adapt to this toxic pollutant. Appl Microbiol Biotechnol 2013; 97:5555-64. [DOI: 10.1007/s00253-013-4796-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2013] [Revised: 02/17/2013] [Accepted: 02/19/2013] [Indexed: 11/27/2022]
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10
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Genomic organization and biochemistry of the ribulose monophosphate pathway and its application in biotechnology. Appl Microbiol Biotechnol 2009; 84:407-16. [DOI: 10.1007/s00253-009-2120-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2009] [Revised: 06/30/2009] [Accepted: 06/30/2009] [Indexed: 10/20/2022]
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C(1) compounds as auxiliary substrate for engineered Pseudomonas putida S12. Appl Microbiol Biotechnol 2009; 83:705-13. [PMID: 19280184 PMCID: PMC2690845 DOI: 10.1007/s00253-009-1922-y] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2008] [Revised: 02/18/2009] [Accepted: 02/18/2009] [Indexed: 11/17/2022]
Abstract
The solvent-tolerant bacterium Pseudomonas putida S12 was engineered to efficiently utilize the C1 compounds methanol and formaldehyde as auxiliary substrate. The hps and phi genes of Bacillus brevis, encoding two key steps of the ribulose monophosphate (RuMP) pathway, were introduced to construct a pathway for the metabolism of the toxic methanol oxidation intermediate formaldehyde. This approach resulted in a remarkably increased biomass yield on the primary substrate glucose when cultured in C-limited chemostats fed with a mixture of glucose and formaldehyde. With increasing relative formaldehyde feed concentrations, the biomass yield increased from 35% (C-mol biomass/C-mol glucose) without formaldehyde to 91% at 60% relative formaldehyde concentration. The RuMP-pathway expressing strain was also capable of growing to higher relative formaldehyde concentrations than the control strain. The presence of an endogenous methanol oxidizing enzyme activity in P. putida S12 allowed the replacement of formaldehyde with the less toxic methanol, resulting in an 84% (C-mol/C-mol) biomass yield. Thus, by introducing two enzymes of the RuMP pathway, co-utilization of the cheap and renewable substrate methanol was achieved, making an important contribution to the efficient use of P. putida S12 as a bioconversion platform host.
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12
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Current awareness on yeast. Yeast 2008. [DOI: 10.1002/yea.1559] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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