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Kurashiki R, Takahashi M, Okumura Y, Ono T, Endo H, Makino K, Fukui K, Yokoyama K, Ishikawa S, Yoshida KI, Ohshiro T, Suzuki H. Efficient pathway-driven scyllo-inositol production from myo-inositol using thermophilic cells and mesophilic inositol dehydrogenases: a novel strategy for pathway control. Appl Environ Microbiol 2024; 90:e0028124. [PMID: 38975762 PMCID: PMC11267878 DOI: 10.1128/aem.00281-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2024] [Accepted: 06/08/2024] [Indexed: 07/09/2024] Open
Abstract
Mesophilic enzymes, which are active at moderate temperatures, may dominate enzymatic reactions even in the presence of thermophilic crude enzymes. This study was conducted to investigate this hypothesis with mesophilic inositol dehydrogenases (IolG and IolX) produced in Geobacillus kaustophilus HTA426. To ensure the efficient production of mesophilic enzymes, we first screened for promoters induced at moderate temperatures using transcriptome analysis and identified four genes highly expressed at 30°C in the thermophile. We further characterized these promoters using fluorescent reporter assays to determine that the mti3 promoter could direct efficient gene expression at 40°C. We cloned the promoter into an Escherichia coli-Geobacillus shuttle plasmid and confirmed that the resulting vector functioned in G. kaustophilus and other thermophiles. We then used this vector for the cooperative expression of the iolG and iolX genes from Bacillus subtilis 168. G. kaustophilus cells carrying the expression vector were incubated at 60°C for cellular propagation and then at 40°C for the production of IolG and IolX. When the cells were permeabilized, IolG and IolX acted as catalysts to convert exogenous myo-inositol into scyllo-inositol at 30°C. In a scaled-up reaction, 10 g of myo-inositol was converted to 1.8 g of scyllo-inositol, which was further purified to yield 970 mg of pure powder. Notably, myo-inositol was degraded by intrinsic enzymes of G. kaustophilus at 60°C but not at 30°C, supporting our initial hypothesis. We indicate that this approach is useful for preparing enzyme cocktails without the need for purification. IMPORTANCE Enzyme cocktails are commonly employed for cell-free chemical synthesis; however, their preparation involves cumbersome processes. This study affirms that mesophilic enzymes in thermophilic crude extracts can function as specific catalysts at moderate temperatures, akin to enzyme cocktails. The catalyst was prepared by permeabilizing cells without the need for concentration, extraction, or purification processes; hence, its preparation was considerably simpler compared with conventional methods for enzyme cocktails. This approach was employed to produce pure scyllo-inositol from an economical substrate. Notably, this marks the first large-scale preparation of pure scyllo-inositol, holding potential pharmaceutical significance as scyllo-inositol serves as a promising agent for certain diseases but is currently expensive. Moreover, this approach holds promise for application in pathway engineering within living cells. The envisioned pathway is designed without chromosomal modification and is simply regulated by switching culture temperatures. Consequently, this study introduces a novel platform for both whole-cell and cell-free synthetic systems.
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Affiliation(s)
- Ryota Kurashiki
- Department of Engineering, Graduate School of Sustainability Science, Tottori University, Tottori, Japan
| | | | - Yuta Okumura
- Department of Engineering, Graduate School of Sustainability Science, Tottori University, Tottori, Japan
| | - Tatsuya Ono
- Department of Engineering, Graduate School of Sustainability Science, Tottori University, Tottori, Japan
| | - Hirofumi Endo
- Department of Chemistry and Biotechnology, Graduate School of Engineering, Tottori University, Tottori, Japan
| | - Kohei Makino
- Graduate School of Science, Technology and Innovation, Kobe University, Kobe, Japan
| | - Kaho Fukui
- Graduate School of Science, Technology and Innovation, Kobe University, Kobe, Japan
| | - Kyosuke Yokoyama
- Graduate School of Science, Technology and Innovation, Kobe University, Kobe, Japan
| | - Shu Ishikawa
- Graduate School of Science, Technology and Innovation, Kobe University, Kobe, Japan
| | - Ken-ichi Yoshida
- Graduate School of Science, Technology and Innovation, Kobe University, Kobe, Japan
| | - Takashi Ohshiro
- Faculty of Engineering, Tottori University, Tottori, Japan
- Center for Research on Green Sustainable Chemistry, Tottori University, Tottori, Japan
| | - Hirokazu Suzuki
- Faculty of Engineering, Tottori University, Tottori, Japan
- Center for Research on Green Sustainable Chemistry, Tottori University, Tottori, Japan
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2
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Yoshida KI, Bott M. Microbial synthesis of health-promoting inositols. Curr Opin Biotechnol 2024; 87:103114. [PMID: 38520822 DOI: 10.1016/j.copbio.2024.103114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Revised: 03/03/2024] [Accepted: 03/04/2024] [Indexed: 03/25/2024]
Abstract
D-chiro-inositol and scyllo-inositol are known for their health-promoting properties and promising as ingredients for functional foods. Strains of Bacillus subtilis and Corynebacterium glutamicum were created by metabolic engineering capable of inexpensive production of these two rare inositols from myo-inositol, which is the most common inositol in nature. In addition, further modifications have enabled the synthesis of the two rare inositols from the much-cheaper carbon sources, glucose or sucrose.
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Affiliation(s)
- Ken-Ichi Yoshida
- Graduate School of Science, Technology and Innovation, University of Kobe, Kobe, Japan.
| | - Michael Bott
- Institute of Bio- and Geosciences, IBG-1: Biotechnology, Forschungszentrum Jülich, Jülich, Germany.
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3
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Wu Y, Kawabata H, Kita K, Ishikawa S, Tanaka K, Yoshida KI. Constitutive glucose dehydrogenase elevates intracellular NADPH levels and luciferase luminescence in Bacillus subtilis. Microb Cell Fact 2022; 21:266. [PMID: 36539761 PMCID: PMC9768902 DOI: 10.1186/s12934-022-01993-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Accepted: 12/13/2022] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND Genetic modifications in Bacillus subtilis have allowed the conversion of myo-inositol into scyllo-inositol, which is proposed as a therapeutic agent for Alzheimer's disease. This conversion comprises two reactions catalyzed by two distinct inositol dehydrogenases, IolG and IolW. The IolW-mediated reaction requires the intracellular regeneration of NADPH, and there appears to be a limit to the endogenous supply of NADPH, which may be one of the rate-determining factors for the conversion of inositol. The primary mechanism of NADPH regeneration in this bacterium remains unclear. RESULTS The gdh gene of B. subtilis encodes a sporulation-specific glucose dehydrogenase that can use NADP+ as a cofactor. When gdh was modified to be constitutively expressed, the intracellular NADPH level was elevated, increasing the conversion of inositol. In addition, the bacterial luciferase derived from Photorhabdus luminescens became more luminescent in cells in liquid culture and colonies on culture plates. CONCLUSION The results indicated that the luminescence of luciferase was representative of intracellular NADPH levels. Luciferase can therefore be employed to screen for mutations in genes involved in NADPH regeneration in B. subtilis, and artificial manipulation to enhance NADPH regeneration can promote the production of substances such as scyllo-inositol.
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Affiliation(s)
- Yuzheng Wu
- grid.31432.370000 0001 1092 3077Department of Science, Technology and Innovation, Kobe University, 1-1 Rokkodai, Nada, Kobe, 657 8501 Japan
| | - Honami Kawabata
- grid.31432.370000 0001 1092 3077Department of Science, Technology and Innovation, Kobe University, 1-1 Rokkodai, Nada, Kobe, 657 8501 Japan
| | - Kyosuke Kita
- grid.31432.370000 0001 1092 3077Department of Science, Technology and Innovation, Kobe University, 1-1 Rokkodai, Nada, Kobe, 657 8501 Japan
| | - Shu Ishikawa
- grid.31432.370000 0001 1092 3077Department of Science, Technology and Innovation, Kobe University, 1-1 Rokkodai, Nada, Kobe, 657 8501 Japan
| | - Kan Tanaka
- grid.32197.3e0000 0001 2179 2105Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, Tokyo, Japan ,grid.419082.60000 0004 1754 9200Core Research for Evolutional Science and Technology, Japan Science and Technology Agency, Tokyo, Japan
| | - Ken-ichi Yoshida
- grid.31432.370000 0001 1092 3077Department of Science, Technology and Innovation, Kobe University, 1-1 Rokkodai, Nada, Kobe, 657 8501 Japan
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4
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Ramp P, Lehnert A, Matamouros S, Wirtz A, Baumgart M, Bott M. Metabolic engineering of Corynebacterium glutamicum for production of scyllo-inositol, a drug candidate against Alzheimer's disease. Metab Eng 2021; 67:173-185. [PMID: 34224896 DOI: 10.1016/j.ymben.2021.06.011] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Revised: 06/17/2021] [Accepted: 06/30/2021] [Indexed: 10/20/2022]
Abstract
Scyllo-inositol has been identified as a potential drug for the treatment of Alzheimer's disease. Therefore, cost-efficient processes for the production of this compound are desirable. In this study, we analyzed and engineered Corynebacterium glutamicum with the aim to develop competitive scyllo-inositol producer strains. Initial studies revealed that C. glutamicum naturally produces scyllo-inositol when cultured with myo-inositol as carbon source. The conversion involves NAD+-dependent oxidation of myo-inositol to 2-keto-myo-inositol followed by NADPH-dependent reduction to scyllo-inositol. Use of myo-inositol for biomass formation was prevented by deletion of a cluster of 16 genes involved in myo-inositol catabolism (strain MB001(DE3)Δiol1). Deletion of a second cluster of four genes (oxiC-cg3390-oxiD-oxiE) related to inositol metabolism prevented conversion of 2-keto-myo-inositol to undesired products causing brown coloration (strain MB001(DE3)Δiol1Δiol2). The two chassis strains were used for plasmid-based overproduction of myo-inositol dehydrogenase (IolG) and scyllo-inositol dehydrogenase (IolW). In BHI medium containing glucose and myo-inositol, a complete conversion of the consumed myo-inositol into scyllo-inositol was achieved with the Δiol1Δiol2 strain. To enable scyllo-inositol production from cheap carbon sources, myo-inositol 1-phosphate synthase (Ino1) and myo-inositol 1-phosphatase (ImpA), which convert glucose 6-phosphate into myo-inositol, were overproduced in addition to IolG and IolW using plasmid pSI. Strain MB001(DE3)Δiol1Δiol2 (pSI) produced 1.8 g/L scyllo-inositol from 20 g/L glucose and even 4.4 g/L scyllo-inositol from 20 g/L sucrose within 72 h. Our results demonstrate that C. glutamicum is an attractive host for the biotechnological production of scyllo-inositol and potentially further myo-inositol-derived products.
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Affiliation(s)
- Paul Ramp
- IBG-1: Biotechnology, Institute of Bio- and Geosciences, Forschungszentrum Jülich, Jülich, Germany
| | - Alexander Lehnert
- IBG-1: Biotechnology, Institute of Bio- and Geosciences, Forschungszentrum Jülich, Jülich, Germany
| | - Susana Matamouros
- IBG-1: Biotechnology, Institute of Bio- and Geosciences, Forschungszentrum Jülich, Jülich, Germany
| | - Astrid Wirtz
- IBG-1: Biotechnology, Institute of Bio- and Geosciences, Forschungszentrum Jülich, Jülich, Germany
| | - Meike Baumgart
- IBG-1: Biotechnology, Institute of Bio- and Geosciences, Forschungszentrum Jülich, Jülich, Germany
| | - Michael Bott
- IBG-1: Biotechnology, Institute of Bio- and Geosciences, Forschungszentrum Jülich, Jülich, Germany.
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Boonluksiri Y, Prapagdee B, Sombatsompop N. Promotion of polylactic acid biodegradation by a combined addition of PLA-degrading bacterium and nitrogen source under submerged and soil burial conditions. Polym Degrad Stab 2021. [DOI: 10.1016/j.polymdegradstab.2021.109562] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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6
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Engineering Bacillus subtilis Cells as Factories: Enzyme Secretion and Value-added Chemical Production. BIOTECHNOL BIOPROC E 2020. [DOI: 10.1007/s12257-020-0104-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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7
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Wang X, Chen L, Liu J, Sun T, Zhang W. Light-Driven Biosynthesis of myo-Inositol Directly From CO 2 in Synechocystis sp. PCC 6803. Front Microbiol 2020; 11:566117. [PMID: 33117313 PMCID: PMC7550737 DOI: 10.3389/fmicb.2020.566117] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Accepted: 09/11/2020] [Indexed: 11/13/2022] Open
Abstract
myo-inositol (MI) is an essential growth factor, nutritional source, and important precursor for many derivatives like D-chiro-inositol. In this study, attempts were made to achieve the “green biosynthesis” of MI in a model photosynthetic cyanobacterium Synechocystis sp. PCC 6803. First, several genes encoding myo-inositol-1-phosphate synthases and myo-inositol-1-monophosphatase, catalyzing the first or the second step of MI synthesis, were introduced, respectively, into Synechocystis. The results showed that the engineered strain carrying myo-inositol-1-phosphate synthase gene from Saccharomyces cerevisiae was able to produce MI at 0.97 mg L–1. Second, the combined overexpression of genes related to the two catalyzing processes increased the production up to 1.42 mg L–1. Third, to re-direct more cellular carbon flux into MI synthesis, an inducible small RNA regulatory tool, based on MicC-Hfq, was utilized to control the competing pathways of MI biosynthesis, resulting in MI production of ∼7.93 mg L–1. Finally, by optimizing the cultivation condition via supplying bicarbonate to enhance carbon fixation, a final MI production up to 12.72 mg L–1 was achieved, representing a ∼12-fold increase compared with the initial MI-producing strain. This study provides a light-driven green synthetic strategy for MI directly from CO2 in cyanobacterial chassis and represents a renewable alternative that may deserve further optimization in the future.
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Affiliation(s)
- Xiaoshuai Wang
- Laboratory of Synthetic Microbiology, School of Chemical Engineering and Technology, Tianjin University, Tianjin, China.,Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering, Ministry of Education of China, Tianjin, China.,Collaborative Innovation Center of Chemical Science and Engineering, Tianjin, China
| | - Lei Chen
- Laboratory of Synthetic Microbiology, School of Chemical Engineering and Technology, Tianjin University, Tianjin, China.,Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering, Ministry of Education of China, Tianjin, China.,Collaborative Innovation Center of Chemical Science and Engineering, Tianjin, China
| | - Jing Liu
- School of Life Sciences, Tianjin University, Tianjin, China
| | - Tao Sun
- Laboratory of Synthetic Microbiology, School of Chemical Engineering and Technology, Tianjin University, Tianjin, China.,Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering, Ministry of Education of China, Tianjin, China.,Center for Biosafety Research and Strategy, Tianjin University, Tianjin, China
| | - Weiwen Zhang
- Laboratory of Synthetic Microbiology, School of Chemical Engineering and Technology, Tianjin University, Tianjin, China.,Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering, Ministry of Education of China, Tianjin, China.,Collaborative Innovation Center of Chemical Science and Engineering, Tianjin, China.,Center for Biosafety Research and Strategy, Tianjin University, Tianjin, China
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8
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Michon C, Kang CM, Karpenko S, Tanaka K, Ishikawa S, Yoshida KI. A bacterial cell factory converting glucose into scyllo-inositol, a therapeutic agent for Alzheimer's disease. Commun Biol 2020; 3:93. [PMID: 32123276 PMCID: PMC7052218 DOI: 10.1038/s42003-020-0814-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2019] [Accepted: 02/11/2020] [Indexed: 12/28/2022] Open
Abstract
A rare stereoisomer of inositol, scyllo-inositol, is a therapeutic agent that has shown potential efficacy in preventing Alzheimer’s disease. Mycobacterium tuberculosis ino1 encoding myo-inositol-1-phosphate (MI1P) synthase (MI1PS) was introduced into Bacillus subtilis to convert glucose-6-phosphate (G6P) into MI1P. We found that inactivation of pbuE elevated intracellular concentrations of NAD+·NADH as an essential cofactor of MI1PS and was required to activate MI1PS. MI1P thus produced was dephosphorylated into myo-inositol by an intrinsic inositol monophosphatase, YktC, which was subsequently isomerized into scyllo-inositol via a previously established artificial pathway involving two inositol dehydrogenases, IolG and IolW. In addition, both glcP and glcK were overexpressed to feed more G6P and accelerate scyllo-inositol production. Consequently, a B. subtilis cell factory was demonstrated to produce 2 g L−1scyllo-inositol from 20 g L−1 glucose. This cell factory provides an inexpensive way to produce scyllo-inositol, which will help us to challenge the growing problem of Alzheimer’s disease in our aging society. Michon et al. describe the use of a recombinant Bacillus subtilis as a cell factory capable of producing scyllo-inositol, a therapeutic compound for Alzheimer’s disease, from inexpensive glucose. They demonstrate that it could produce 2 g L−1 of scyllo-inositol from 20 g L−1 glucose.
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Affiliation(s)
- Christophe Michon
- Department of Science, Technology and Innovation, Kobe University, Kobe, 657 8501, Japan.,CHROMagar, 4 Place du 18 Juin 1940, 75006, Paris, France
| | - Choong-Min Kang
- Department of Biological Sciences, California State University, Stanislaus, Turlock, CA, 95382, USA
| | - Sophia Karpenko
- Department of Science, Technology and Innovation, Kobe University, Kobe, 657 8501, Japan.,Sorbonne Universités, UPMC Univ. Paris 06, UMR 8237, Laboratoire Jean Perrin, F-75005, Paris, France.,CNRS UMR 8237, Laboratoire Jean Perrin, F-75005, Paris, France.,Paris Sciences & Lettres, 60 rue Mazarine, F-75006, Paris, France
| | - Kosei Tanaka
- Department of Science, Technology and Innovation, Kobe University, Kobe, 657 8501, Japan
| | - Shu Ishikawa
- Department of Science, Technology and Innovation, Kobe University, Kobe, 657 8501, Japan
| | - Ken-Ichi Yoshida
- Department of Science, Technology and Innovation, Kobe University, Kobe, 657 8501, Japan.
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Li Y, Liu S, You C. Permeabilized
Escherichia coli
Whole Cells Containing Co‐Expressed Two Thermophilic Enzymes Facilitate the Synthesis of
scyllo
‐Inositol from
myo
‐Inositol. Biotechnol J 2019; 15:e1900191. [DOI: 10.1002/biot.201900191] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Revised: 08/28/2019] [Indexed: 12/17/2022]
Affiliation(s)
- Yuan Li
- Tianjin Institute of Industrial BiotechnologyChinese Academy of Sciences Tianjin 300308 P. R. China
| | - Shan Liu
- Tianjin Institute of Industrial BiotechnologyChinese Academy of Sciences Tianjin 300308 P. R. China
| | - Chun You
- Tianjin Institute of Industrial BiotechnologyChinese Academy of Sciences Tianjin 300308 P. R. China
- University of Chinese Academy of Sciences Beijing 100049 China
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10
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Aamudalapalli HB, Bertwistle D, Palmer DRJ, Sanders DAR. myo-Inositol dehydrogenase and scyllo-inositol dehydrogenase from Lactobacillus casei BL23 bind their substrates in very different orientations. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2018; 1866:1115-1124. [PMID: 30282609 DOI: 10.1016/j.bbapap.2018.08.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2018] [Revised: 08/24/2018] [Accepted: 08/28/2018] [Indexed: 10/28/2022]
Abstract
Many bacteria can use myo-inositol as the sole carbon source using enzymes encoded in the iol operon. The first step is catalyzed by the well-characterized myo-inositol dehydrogenase (mIDH), which oxidizes the axial hydroxyl group of the substrate to form scyllo-inosose. Some bacteria, including Lactobacillus casei, contain more than one apparent mIDH-encoding gene in the iol operon, but such redundant enzymes have not been investigated. scyllo-Inositol, a stereoisomer of myo-inositol, is not a substrate for mIDH, but scyllo-inositol dehydrogenase (sIDH) enzymes have been reported, though never observed to be encoded within the iol operon. Sequences indicate these enzymes are related, but the structural basis by which they distinguish their substrates has not been determined. Here we report the substrate selectivity, kinetics, and high-resolution crystal structures of the proteins encoded by iolG1 and iolG2 from L. casei BL23, which we show encode a mIDH and sIDH, respectively. Comparison of the ternary complex of each enzyme with its preferred substrate reveals the key variations allowing for oxidation of an equatorial versus an axial hydroxyl group. Despite the overall similarity of the active site residues, scyllo-inositol is bound in an inverted, tilted orientation by sIDH relative to the orientation of myo-inositol by mIDH.
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Affiliation(s)
| | - Drew Bertwistle
- Department of Physics and Engineering Physics, University of Saskatchewan, Canada; Canadian Light Source, University of Saskatchewan, Canada
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Whitfield H, Riley AM, Diogenous S, Godage HY, Potter BVL, Brearley CA. Simple synthesis of 32P-labelled inositol hexakisphosphates for study of phosphate transformations. PLANT AND SOIL 2018; 427:149-161. [PMID: 29880988 PMCID: PMC5984642 DOI: 10.1007/s11104-017-3315-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Accepted: 06/12/2017] [Indexed: 06/08/2023]
Abstract
BACKGROUND AND AIMS In many soils inositol hexakisphosphate in its various forms is as abundant as inorganic phosphate. The organismal and geochemical processes that exchange phosphate between inositol hexakisphosphate and other pools of soil phosphate are poorly defined, as are the organisms and enzymes involved. We rationalized that simple enzymic synthesis of inositol hexakisphosphate labeled with 32P would greatly enable study of transformation of soil inositol phosphates when combined with robust HPLC separations of different inositol phosphates. METHODS We employed the enzyme inositol pentakisphosphate 2-kinase, IP5 2-K, to transfer phosphate from [γ-32P]ATP to axial hydroxyl(s) of myo-, neo- and 1D-chiro-inositol phosphate substrates. RESULTS 32P-labeled inositol phosphates were separated by anion exchange HPLC with phosphate eluents. Additional HPLC methods were developed to allow facile separation of myo-, neo-, 1D-chiro- and scyllo-inositol hexakisphosphate on acid gradients. CONCLUSIONS We developed enzymic approaches that allow the synthesis of labeled myo-inositol 1,[32P]2,3,4,5,6-hexakisphosphate; neo-inositol 1,[32P]2,3,4,[32P]5,6 - hexakisphosphate and 1D-chiro-inositol [32P]1,2,3,4,5,[32P]6-hexakisphosphate. Additionally, we describe HPLC separations of all inositol hexakisphosphates yet identified in soils, using a collection of soil inositol phosphates described in the seminal historic studies of Cosgrove, Tate and coworkers. Our study will enable others to perform radiotracer experiments to analyze fluxes of phosphate to/from inositol hexakisphosphates in different soils.
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Affiliation(s)
- Hayley Whitfield
- School of Biological Sciences, University of Norwich, Norwich Research Park, Norwich, NR4 7TJ UK
| | - Andrew M. Riley
- Medicinal Chemistry & Drug Discovery, Department of Pharmacology, University of Oxford, Mansfield Rd, Oxford, OX1 3QT UK
| | - Soulla Diogenous
- Wolfson Laboratory of Medicinal Chemistry, Department of Pharmacy and Pharmacology, University of Bath, Bath, BA2 7AY UK
| | - Himali Y. Godage
- Wolfson Laboratory of Medicinal Chemistry, Department of Pharmacy and Pharmacology, University of Bath, Bath, BA2 7AY UK
| | - Barry V. L. Potter
- Medicinal Chemistry & Drug Discovery, Department of Pharmacology, University of Oxford, Mansfield Rd, Oxford, OX1 3QT UK
- Wolfson Laboratory of Medicinal Chemistry, Department of Pharmacy and Pharmacology, University of Bath, Bath, BA2 7AY UK
| | - Charles A. Brearley
- School of Biological Sciences, University of Norwich, Norwich Research Park, Norwich, NR4 7TJ UK
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12
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Tanaka K, Natsume A, Ishikawa S, Takenaka S, Yoshida KI. A new-generation of Bacillus subtilis cell factory for further elevated scyllo-inositol production. Microb Cell Fact 2017; 16:67. [PMID: 28431560 PMCID: PMC5401388 DOI: 10.1186/s12934-017-0682-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2016] [Accepted: 04/14/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND A stereoisomer of inositol, scyllo-inositol (SI), has been regarded as a promising therapeutic agent for Alzheimer's disease. However, this compound is relatively rare, whereas another stereoisomer of inositol, myo-inositol (MI) is abundant in nature. Bacillus subtilis 168 has the ability to metabolize inositol stereoisomers, including MI and SI. Previously, we reported a B. subtilis cell factory with modified inositol metabolism that converts MI into SI in the culture medium. The strain was constructed by deleting all genes related to inositol metabolism and overexpressing key enzymes, IolG and IolW. By using this strain, 10 g/l of MI initially included in the medium was completely converted into SI within 48 h of cultivation in a rich medium containing 2% (w/v) Bacto soytone. RESULTS When the initial concentration of MI was increased to 50 g/l, conversion was limited to 15.1 g/l of SI. Therefore, overexpression systems of IolT and PntAB, the main transporter of MI in B. subtilis and the membrane-integral nicotinamide nucleotide transhydrogenase in Escherichia coli respectively, were additionally introduced into the B. subtilis cell factory, but the conversion efficiency hardly improved. We systematically determined the amount of Bacto soytone necessary for ultimate conversion, which was 4% (w/v). As a result, the conversion of SI reached to 27.6 g/l within 48 h of cultivation. CONCLUSIONS The B. subtilis cell factory was improved to yield a SI production rate of 27.6 g/l/48 h by simultaneous overexpression of IolT and PntAB, and by addition of 4% (w/v) Bacto soytone in the conversion medium. The concentration of SI was increased even in the stationary phase perhaps due to nutrients in the Bacto soytone that contribute to the conversion process. Thus, MI conversion to SI may be further optimized via identification and control of these unknown nutrients.
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Affiliation(s)
- Kosei Tanaka
- Organization of Advanced Science and Technology, Kobe University, Kobe, Japan
| | - Ayane Natsume
- Graduate School of Agricultural Science, Department of Agrobioscience, Kobe University, Kobe, Japan
| | - Shu Ishikawa
- Graduate School of Science, Technology and Innovation, Department of Science, Technology and Innovation, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe, Hyogo, 657-8501, Japan
| | - Shinji Takenaka
- Graduate School of Agricultural Science, Department of Agrobioscience, Kobe University, Kobe, Japan
| | - Ken-Ichi Yoshida
- Graduate School of Science, Technology and Innovation, Department of Science, Technology and Innovation, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe, Hyogo, 657-8501, Japan.
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Kang DM, Tanaka K, Takenaka S, Ishikawa S, Yoshida KI. Bacillus subtilis iolU encodes an additional NADP +-dependent scyllo-inositol dehydrogenase. Biosci Biotechnol Biochem 2017; 81:1026-1032. [PMID: 28043209 DOI: 10.1080/09168451.2016.1268043] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Bacillus subtilis genes iolG, iolW, iolX, ntdC, yfiI, yrbE, yteT, and yulF belong to the Gfo/Idh/MocA family. The functions of iolG, iolW, iolX, and ntdC are known; however, the functions of the others are unknown. We previously reported the B. subtilis cell factory simultaneously overexpressing iolG and iolW to achieve bioconversion of myo-inositol (MI) into scyllo-inositol (SI). YulF shares a significant similarity with IolW, the NADP+-dependent SI dehydrogenase. Transcriptional abundance of yulF did not correlate to that of iol genes involved in inositol metabolism. However, when yulF was overexpressed instead of iolW in the B. subtilis cell factory, SI was produced from MI, suggesting a similar function to iolW. In addition, we demonstrated that recombinant His6-tagged YulF converted scyllo-inosose into SI in an NADPH-dependent manner. We have thus identified yulF encoding an additional NADP+-dependent SI dehydrogenase, which we propose to rename iolU.
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Affiliation(s)
- Dong-Min Kang
- a Department of Agrobioscience , Graduate School of Agricultural Science, Kobe University , Kobe , Japan
| | - Kosei Tanaka
- b Organization of Advanced Science and Technology , Kobe University , Kobe , Japan
| | - Shinji Takenaka
- a Department of Agrobioscience , Graduate School of Agricultural Science, Kobe University , Kobe , Japan.,b Organization of Advanced Science and Technology , Kobe University , Kobe , Japan
| | - Shu Ishikawa
- c Department of Science, Technology and Innovation, Graduate School of Science, Technology and Innovation , Kobe University , Kobe , Japan
| | - Ken-Ichi Yoshida
- b Organization of Advanced Science and Technology , Kobe University , Kobe , Japan.,c Department of Science, Technology and Innovation, Graduate School of Science, Technology and Innovation , Kobe University , Kobe , Japan
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Liu Y, Li J, Du G, Chen J, Liu L. Metabolic engineering of Bacillus subtilis fueled by systems biology: Recent advances and future directions. Biotechnol Adv 2017; 35:20-30. [DOI: 10.1016/j.biotechadv.2016.11.003] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Revised: 10/21/2016] [Accepted: 11/16/2016] [Indexed: 12/25/2022]
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Advances and needs for endotoxin-free production strains. Appl Microbiol Biotechnol 2015; 99:9349-60. [PMID: 26362682 DOI: 10.1007/s00253-015-6947-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2015] [Revised: 08/16/2015] [Accepted: 08/20/2015] [Indexed: 10/23/2022]
Abstract
The choice of an appropriate microbial host cell and suitable production conditions is crucial for the downstream processing of pharmaceutical- and food-grade products. Although Escherichia coli serves as a highly valuable leading platform for the production of value-added products, like most Gram-negative bacteria, this bacterium contains a potent immunostimulatory lipopolysaccharide (LPS), referred to as an endotoxin. In contrast, Gram-positive bacteria, notably Bacillus, lactic acid bacteria (LAB), Corynebacterium, and yeasts have been extensively used as generally recognized as safe (GRAS) endotoxin-free platforms for the production of a variety of products. This review summarizes the currently available knowledge on the utilization of these representative Gram-positive bacteria for the production of eco- and bio-friendly products, particularly natural polyesters, polyhydroxyalkanoates, bacteriocins, and membrane proteins. The successful case studies presented here serve to inspire the use of these microorganisms as a main-player or by-player depending on their individual properties for the industrial production of these desirable targets.
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Tanaka K, Takanaka S, Yoshida KI. A second-generation Bacillus cell factory for rare inositol production. Bioengineered 2015; 5:331-4. [PMID: 25482235 DOI: 10.4161/bioe.29897] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Some rare inositol stereoisomers are known to exert specific health-promoting effects, including scyllo-inositol (SI), which is a promising therapeutic agent for Alzheimer disease. We recently reported a Bacillus subtilis cell factory that performed the efficient production of SI from the cheapest and most abundant isomer myo-inositol (MI). In the cell factory all "useless" genes involved in MI and SI metabolism were deleted and overexpression of the key enzymes, IolG and IolW, was appended. It converted 10 g/L MI into the same amount of SI in 48 h of cultivation. In this addendum, we discuss further improvement in the cell factory and its possible applications.
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Affiliation(s)
- Kosei Tanaka
- a Organization of Advanced Science and Technology; Kobe University; Kobe, Japan
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