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Kang JI, Seo JH, Park CI, Kim ST, Kim YK, Jang JK, Kwon CO, Jeon S, Kim HW, Kim SJ. Microbiome analysis of circulating bacterial extracellular vesicles in obsessive-compulsive disorder. Psychiatry Clin Neurosci 2023; 77:646-652. [PMID: 37646189 DOI: 10.1111/pcn.13593] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2023] [Revised: 08/07/2023] [Accepted: 08/24/2023] [Indexed: 09/01/2023]
Abstract
AIM The present study examined the microbiome abundance and composition of drug-naive or drug-free patients with obsessive-compulsive disorder (OCD) compared with healthy controls. In addition, in the OCD group, the microbiome composition was compared between early-onset and late-onset OCD. METHODS Serum samples were collected from 89 patients with OCD and 107 age- and sex-matched healthy controls. Bacterial DNA was isolated from bacteria-derived extracellular vesicles in serum and then amplified and quantified using primers specific to the V3-V4 hypervariable region of the 16S ribosomal RNA gene. The 16S ribosomal DNA gene amplicon sequencing was performed. RESULTS The pooled estimate showed that α-diversity was significantly reduced in patients with OCD compared with that in healthy controls (PShannon = 0.00015). In addition, a statistically significant difference was observed in β-diversity between patients with OCD and healthy controls at the order (P = 0.012), family (P = 0.003), genus (P < 0.001), and species (P = 0.005) levels. In the microbiome composition, Pseudomonas, Caulobacteraceae (f), Streptococcus, Novosphingobium, and Enhydrobacter at the genus level were significantly less prevalent in patients with OCD than in controls. In addition, among patients with OCD, the microbial composition in the early-onset versus late-onset types was significantly different with respect to the genera Corynebacterium and Pelomonas. CONCLUSION The present study showed an aberrant microbiome in patients with OCD, suggesting a role of the microbiota-brain interaction in the pathophysiology of OCD. Further longitudinal studies with larger sample sizes adjusting for various confounders are warranted.
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Affiliation(s)
- Jee In Kang
- Department of Psychiatry, Yonsei University College of Medicine, Seoul, Republic of Korea
- Institute of Behavioral Science in Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Jun Ho Seo
- Institute of Behavioral Science in Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea
- Department of Psychiatry, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea
| | - Chun Il Park
- Institute of Behavioral Science in Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea
- Department of Psychiatry, CHA Bundang Medical Center, CHA University, Seongnam, Republic of Korea
| | - Shin Tae Kim
- Department of Psychiatry, Yonsei University College of Medicine, Seoul, Republic of Korea
- Institute of Behavioral Science in Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea
| | | | | | | | - Sumoa Jeon
- Institute of Behavioral Science in Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Hae Won Kim
- Institute of Behavioral Science in Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea
- Department of Medical Education, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Se Joo Kim
- Department of Psychiatry, Yonsei University College of Medicine, Seoul, Republic of Korea
- Institute of Behavioral Science in Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea
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Kataoka N, Matsushita K, Yakushi T. Development of a 2-hydroxyglutarate production system by Corynebacterium glutamicum. Appl Microbiol Biotechnol 2023; 107:5987-5997. [PMID: 37555949 DOI: 10.1007/s00253-023-12716-9] [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: 05/17/2023] [Revised: 07/23/2023] [Accepted: 07/28/2023] [Indexed: 08/10/2023]
Abstract
2-Oxoglutarate (2-OG) is a tricarboxylate cycle intermediate that can be biologically converted into several industrially important compounds. However, studies on the fermentative production of compounds synthesized from 2-OG, but not via glutamate (defined as 2-OG derivatives), have been limited. Herein, a system that can efficiently produce 2-hydroxyglutarate (2-HG), a 2-OG derivative biosynthesized by the hgdH-encoded NADH-dependent 2-HG dehydrogenase of Acidaminococcus fermentans, was developed as a model using Corynebacterium glutamicum. First, the D3 strain, which lacked the two NADH-consuming enzymes, lactate dehydrogenase and malate dehydrogenase, as well as isocitrate lyase, was constructed as a starting strain. Next, the growth conditions that induced the accumulation of 2-OG were investigated, and it was found that the biotin- and nitrogen-limited (B/N-limited) aerobic growth conditions were suitable for this purpose. Finally, the hgdH gene of A. fermentans became overexpressed in the D3 strain by inserting it into the intergenic regions with the strong constitutive promoter of the tuf gene of C. glutamicum; the engineered strain was cultured under the B/N-limited aerobic growth conditions. The engineered strain produced 80.1 mM 2-HG with a yield of 0.390 mol/mol glucose, which are the highest titer and yield reported thus far, to the best of our knowledge. Furthermore, reverse genetics showed that the produced 2-HG was partially exported via the YggB protein (NCgl1221 protein, a mechanosensitive channel) known as an exporter for glutamate under the conditions used herein. KEY POINTS: • An efficient 2-HG production system was developed with Corynebacterium glutamicum. • Biotin- and nitrogen-limited aerobic growth conditions induced 2-OG production. • Produced 2-HG was partially excreted via the glutamate exporter, YggB.
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Affiliation(s)
- Naoya Kataoka
- Department of Biological Chemistry, Faculty of Agriculture, Yamaguchi University, Yamaguchi, Japan.
- Research Center for Thermotolerant Microbial Resources, Yamaguchi University, Yamaguchi, Japan.
| | - Kazunobu Matsushita
- Department of Biological Chemistry, Faculty of Agriculture, Yamaguchi University, Yamaguchi, Japan
- Research Center for Thermotolerant Microbial Resources, Yamaguchi University, Yamaguchi, Japan
| | - Toshiharu Yakushi
- Department of Biological Chemistry, Faculty of Agriculture, Yamaguchi University, Yamaguchi, Japan
- Research Center for Thermotolerant Microbial Resources, Yamaguchi University, Yamaguchi, Japan
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3
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Werner F, Schwardmann LS, Siebert D, Rückert-Reed C, Kalinowski J, Wirth MT, Hofer K, Takors R, Wendisch VF, Blombach B. Metabolic engineering of Corynebacterium glutamicum for fatty alcohol production from glucose and wheat straw hydrolysate. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2023; 16:116. [PMID: 37464396 DOI: 10.1186/s13068-023-02367-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Accepted: 07/07/2023] [Indexed: 07/20/2023]
Abstract
BACKGROUND Fatty acid-derived products such as fatty alcohols (FAL) find growing application in cosmetic products, lubricants, or biofuels. So far, FAL are primarily produced petrochemically or through chemical conversion of bio-based feedstock. Besides the well-known negative environmental impact of using fossil resources, utilization of bio-based first-generation feedstock such as palm oil is known to contribute to the loss of habitat and biodiversity. Thus, the microbial production of industrially relevant chemicals such as FAL from second-generation feedstock is desirable. RESULTS To engineer Corynebacterium glutamicum for FAL production, we deregulated fatty acid biosynthesis by deleting the transcriptional regulator gene fasR, overexpressing a fatty acyl-CoA reductase (FAR) gene of Marinobacter hydrocarbonoclasticus VT8 and attenuating the native thioesterase expression by exchange of the ATG to a weaker TTG start codon. C. glutamicum ∆fasR cg2692TTG (pEKEx2-maqu2220) produced in shaking flasks 0.54 ± 0.02 gFAL L-1 from 20 g glucose L-1 with a product yield of 0.054 ± 0.001 Cmol Cmol-1. To enable xylose utilization, we integrated xylA encoding the xylose isomerase from Xanthomonas campestris and xylB encoding the native xylulose kinase into the locus of actA. This approach enabled growth on xylose. However, adaptive laboratory evolution (ALE) was required to improve the growth rate threefold to 0.11 ± 0.00 h-1. The genome of the evolved strain C. glutamicum gX was re-sequenced, and the evolved genetic module was introduced into C. glutamicum ∆fasR cg2692TTG (pEKEx2-maqu2220) which allowed efficient growth and FAL production on wheat straw hydrolysate. FAL biosynthesis was further optimized by overexpression of the pntAB genes encoding the membrane-bound transhydrogenase of E. coli. The best-performing strain C. glutamicum ∆fasR cg2692TTG CgLP12::(Ptac-pntAB-TrrnB) gX (pEKEx2-maqu2220) produced 2.45 ± 0.09 gFAL L-1 with a product yield of 0.054 ± 0.005 Cmol Cmol-1 and a volumetric productivity of 0.109 ± 0.005 gFAL L-1 h-1 in a pulsed fed-batch cultivation using wheat straw hydrolysate. CONCLUSION The combination of targeted metabolic engineering and ALE enabled efficient FAL production in C. glutamicum from wheat straw hydrolysate for the first time. Therefore, this study provides useful metabolic engineering principles to tailor this bacterium for other products from this second-generation feedstock.
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Affiliation(s)
- Felix Werner
- Microbial Biotechnology, Campus Straubing for Biotechnology and Sustainability, Technical University of Munich, Uferstraße 53, 94315, Straubing, Germany
| | - Lynn S Schwardmann
- Genetics of Prokaryotes, Faculty of Biology and CeBiTec, Bielefeld University, Bielefeld, Germany
| | - Daniel Siebert
- Microbial Biotechnology, Campus Straubing for Biotechnology and Sustainability, Technical University of Munich, Uferstraße 53, 94315, Straubing, Germany
- SynBiofoundry@TUM, Technical University of Munich, Straubing, Germany
| | | | - Jörn Kalinowski
- Microbial Genomics and Biotechnology, CeBiTec, Bielefeld University, Bielefeld, Germany
| | - Marie-Theres Wirth
- Microbial Biotechnology, Campus Straubing for Biotechnology and Sustainability, Technical University of Munich, Uferstraße 53, 94315, Straubing, Germany
| | - Katharina Hofer
- Institute of Biochemical Engineering, University of Stuttgart, Stuttgart, Germany
| | - Ralf Takors
- Institute of Biochemical Engineering, University of Stuttgart, Stuttgart, Germany
| | - Volker F Wendisch
- Genetics of Prokaryotes, Faculty of Biology and CeBiTec, Bielefeld University, Bielefeld, Germany
| | - Bastian Blombach
- Microbial Biotechnology, Campus Straubing for Biotechnology and Sustainability, Technical University of Munich, Uferstraße 53, 94315, Straubing, Germany.
- SynBiofoundry@TUM, Technical University of Munich, Straubing, Germany.
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4
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Schwardmann LS, Wu T, Dransfeld AK, Lindner SN, Wendisch VF. Formamide-based production of amines by metabolically engineering Corynebacterium glutamicum. Appl Microbiol Biotechnol 2023:10.1007/s00253-023-12592-3. [PMID: 37246985 DOI: 10.1007/s00253-023-12592-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Revised: 05/09/2023] [Accepted: 05/12/2023] [Indexed: 05/30/2023]
Abstract
Formamide is rarely used as nitrogen source by microorganisms. Therefore, formamide and formamidase have been used as protection system to allow for growth under non-sterile conditions and for non-sterile production of acetoin, a product lacking nitrogen. Here, we equipped Corynebacterium glutamicum, a renowned workhorse for industrial amino acid production for 60 years, with formamidase from Helicobacter pylori 26695, enabling growth with formamide as sole nitrogen source. Thereupon, the formamide/formamidase system was exploited for efficient formamide-based production of the nitrogenous compounds L-glutamate, L-lysine, N-methylphenylalanine, and dipicolinic acid by transfer of the formamide/formamidase system to established producer strains. Stable isotope labeling verified the incorporation of nitrogen from formamide into biomass and the representative product L-lysine. Moreover, we showed ammonium leakage during formamidase-based access of formamide to be exploitable to support growth of formamidase-deficient C. glutamicum in co-cultivation and demonstrated that efficient utilization of formamide as sole nitrogen source benefitted from overexpression of formate dehydrogenase. KEY POINTS: • C. glutamicum was engineered to access formamide. • Formamide-based production of nitrogenous compounds was established. • Nitrogen cross-feeding supported growth of a formamidase-negative strain.
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Affiliation(s)
- Lynn S Schwardmann
- Genetics of Prokaryotes, Faculty of Biology and CeBiTec, Bielefeld University, Universitätsstr. 25, 33615, Bielefeld, Germany
| | - Tong Wu
- Department of Biochemistry, Charité Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität Zu Berlin, Charitéplatz 1, 10117, Berlin, Germany
| | - Aron K Dransfeld
- Genetics of Prokaryotes, Faculty of Biology and CeBiTec, Bielefeld University, Universitätsstr. 25, 33615, Bielefeld, Germany
| | - Steffen N Lindner
- Department of Biochemistry, Charité Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität Zu Berlin, Charitéplatz 1, 10117, Berlin, Germany
| | - Volker F Wendisch
- Genetics of Prokaryotes, Faculty of Biology and CeBiTec, Bielefeld University, Universitätsstr. 25, 33615, Bielefeld, Germany.
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5
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Feng LJ, Zhang KX, Shi ZL, Zhu FP, Yuan XZ, Zong WS, Song C. Aged microplastics enhance their interaction with ciprofloxacin and joint toxicity on Escherichia coli. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2022; 247:114218. [PMID: 36279636 DOI: 10.1016/j.ecoenv.2022.114218] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Revised: 10/12/2022] [Accepted: 10/19/2022] [Indexed: 06/16/2023]
Abstract
Microplastics (MPs) in natural environments undergo complex aging processes, changing their interactions with coexisting antibiotics, and posing unpredictable ecological risks. However, the joint toxicity of aged MPs (aMPs) and antibiotics to bacteria, especially at the molecular level, is unclear. In this study, non-thermal plasma technology was used to simultaneously simulate various radical oxidation and physical reactions that occur naturally in the environment, breaking the limitation of simple aging process in laboratory aging technologies. After aging, we investigated the altered properties of aMPs, their interactions with ciprofloxacin (CIP), and the molecular responses of E. coli exposed to pristine MPs (13.5 mg/L), aMPs (13.5 mg/L), and CIP (2 μg/L) individually or simultaneously. aMPs bound far more CIP to their surfaces than pristine MPs, especially in freshwater ecosystems. Notably, the growth of E. coli exposed to aMPs alone was inhibited, whereas pristine MPs exposure didn't affect the growth of E. coli. Moreover, the most differentially expressed genes in E. coli were induced by the coexposure of aMPs and CIP. Although E. coli depended on chemotaxis to improve its flagellar rotation and escaped the stress of pollutants, the coexposure of aMPs and CIP still caused cell membrane damage, oxidative stress, obstruction of DNA replication, and osmotic imbalance in E. coli. This study filled the knowledge gap between the toxicity of aMPs and pristine MPs coexisting with antibiotics at the transcription level, helping in the accurate assessment of the potential risks of MPs to the environment.
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Affiliation(s)
- Li-Juan Feng
- College of Geography and Environment, Shandong Normal University, Jinan, Shandong 250014, PR China; Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266237, PR China; Hebei Key Laboratory of Wetland Ecology and Conservation, Hengshui, Hebei 053000, PR China
| | - Kai-Xin Zhang
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266237, PR China; School of Eco-Environment, Hebei University, Baoding, Hebei 071002, PR China
| | - Zong-Lin Shi
- Hebei Key Laboratory of Wetland Ecology and Conservation, Hengshui, Hebei 053000, PR China; Department of Life Science, Hengshui College, Hengshui, Hebei 053000, PR China
| | - Fan-Ping Zhu
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266237, PR China
| | - Xian-Zheng Yuan
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266237, PR China
| | - Wan-Song Zong
- College of Geography and Environment, Shandong Normal University, Jinan, Shandong 250014, PR China.
| | - Chao Song
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266237, PR China.
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6
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A biosensor based on oriented immobilization of an engineered L-glutamate oxidase on a screen-printed microchip for detection of L-glutamate in fermentation processes. Food Chem 2022; 405:134792. [DOI: 10.1016/j.foodchem.2022.134792] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Revised: 10/25/2022] [Accepted: 10/26/2022] [Indexed: 11/23/2022]
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7
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Ferrer L, Mindt M, Suarez-Diez M, Jilg T, Zagorščak M, Lee JH, Gruden K, Wendisch VF, Cankar K. Fermentative Indole Production via Bacterial Tryptophan Synthase Alpha Subunit and Plant Indole-3-Glycerol Phosphate Lyase Enzymes. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2022; 70:5634-5645. [PMID: 35500281 PMCID: PMC9100643 DOI: 10.1021/acs.jafc.2c01042] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Revised: 04/14/2022] [Accepted: 04/18/2022] [Indexed: 06/14/2023]
Abstract
Indole is produced in nature by diverse organisms and exhibits a characteristic odor described as animal, fecal, and floral. In addition, it contributes to the flavor in foods, and it is applied in the fragrance and flavor industry. In nature, indole is synthesized either from tryptophan by bacterial tryptophanases (TNAs) or from indole-3-glycerol phosphate (IGP) by plant indole-3-glycerol phosphate lyases (IGLs). While it is widely accepted that the tryptophan synthase α-subunit (TSA) has intrinsically low IGL activity in the absence of the tryptophan synthase β-subunit, in this study, we show that Corynebacterium glutamicum TSA functions as a bona fide IGL and can support fermentative indole production in strains providing IGP. By bioprospecting additional bacterial TSAs and plant IGLs that function as bona fide IGLs were identified. Capturing indole in an overlay enabled indole production to titers of about 0.7 g L-1 in fermentations using C. glutamicum strains expressing either the endogenous TSA gene or the IGL gene from wheat.
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Affiliation(s)
- Lenny Ferrer
- Genetics
of Prokaryotes, Faculty of Biology & CeBiTec, Bielefeld University, 33615 Bielefeld, Germany
| | - Melanie Mindt
- Wageningen
Plant Research, Wageningen University &
Research, 6708PB Wageningen, The Netherlands
- Axxence
Aromatic GmbH, 46446 Emmerich am Rhein, Germany
| | - Maria Suarez-Diez
- Laboratory
of Systems and Synthetic Biology, Wageningen
University & Research, 6708WE Wageningen, The Netherlands
| | - Tatjana Jilg
- Genetics
of Prokaryotes, Faculty of Biology & CeBiTec, Bielefeld University, 33615 Bielefeld, Germany
| | - Maja Zagorščak
- Department
of Biotechnology and Systems Biology, National
Institute of Biology, 1000 Ljubljana, Slovenia
| | - Jin-Ho Lee
- Department
of Food Science & Biotechnology, Kyungsung
University, 608-736 Busan, Republic of Korea
| | - Kristina Gruden
- Department
of Biotechnology and Systems Biology, National
Institute of Biology, 1000 Ljubljana, Slovenia
| | - Volker F. Wendisch
- Genetics
of Prokaryotes, Faculty of Biology & CeBiTec, Bielefeld University, 33615 Bielefeld, Germany
| | - Katarina Cankar
- Wageningen
Plant Research, Wageningen University &
Research, 6708PB Wageningen, The Netherlands
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Prell C, Busche T, Rückert C, Nolte L, Brandenbusch C, Wendisch VF. Adaptive laboratory evolution accelerated glutarate production by Corynebacterium glutamicum. Microb Cell Fact 2021; 20:97. [PMID: 33971881 PMCID: PMC8112011 DOI: 10.1186/s12934-021-01586-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Accepted: 04/26/2021] [Indexed: 01/16/2023] Open
Abstract
BACKGROUND The demand for biobased polymers is increasing steadily worldwide. Microbial hosts for production of their monomeric precursors such as glutarate are developed. To meet the market demand, production hosts have to be improved constantly with respect to product titers and yields, but also shortening bioprocess duration is important. RESULTS In this study, adaptive laboratory evolution was used to improve a C. glutamicum strain engineered for production of the C5-dicarboxylic acid glutarate by flux enforcement. Deletion of the L-glutamic acid dehydrogenase gene gdh coupled growth to glutarate production since two transaminases in the glutarate pathway are crucial for nitrogen assimilation. The hypothesis that strains selected for faster glutarate-coupled growth by adaptive laboratory evolution show improved glutarate production was tested. A serial dilution growth experiment allowed isolating faster growing mutants with growth rates increasing from 0.10 h-1 by the parental strain to 0.17 h-1 by the fastest mutant. Indeed, the fastest growing mutant produced glutarate with a twofold higher volumetric productivity of 0.18 g L-1 h-1 than the parental strain. Genome sequencing of the evolved strain revealed candidate mutations for improved production. Reverse genetic engineering revealed that an amino acid exchange in the large subunit of L-glutamic acid-2-oxoglutarate aminotransferase was causal for accelerated glutarate production and its beneficial effect was dependent on flux enforcement due to deletion of gdh. Performance of the evolved mutant was stable at the 2 L bioreactor-scale operated in batch and fed-batch mode in a mineral salts medium and reached a titer of 22.7 g L-1, a yield of 0.23 g g-1 and a volumetric productivity of 0.35 g L-1 h-1. Reactive extraction of glutarate directly from the fermentation broth was optimized leading to yields of 58% and 99% in the reactive extraction and reactive re-extraction step, respectively. The fermentation medium was adapted according to the downstream processing results. CONCLUSION Flux enforcement to couple growth to operation of a product biosynthesis pathway provides a basis to select strains growing and producing faster by adaptive laboratory evolution. After identifying candidate mutations by genome sequencing causal mutations can be identified by reverse genetics. As exemplified here for glutarate production by C. glutamicum, this approach allowed deducing rational metabolic engineering strategies.
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Affiliation(s)
- Carina Prell
- Genetics of Prokaryotes, Faculty of Biology & CeBiTec, Bielefeld University, Universitätsstr. 25, 33615 Bielefeld, Germany
| | - Tobias Busche
- Technology Platform Genomics, Center for Biotechnology (CeBiTec), Bielefeld University, Sequenz 1, 33615 Bielefeld, Germany
| | - Christian Rückert
- Technology Platform Genomics, Center for Biotechnology (CeBiTec), Bielefeld University, Sequenz 1, 33615 Bielefeld, Germany
| | - Lea Nolte
- Laboratory of Thermodynamics, Department of Biochemical and Chemical Engineering, TU Dortmund University, Emil-Figge-Str. 70, 44227 Dortmund, Germany
| | - Christoph Brandenbusch
- Laboratory of Thermodynamics, Department of Biochemical and Chemical Engineering, TU Dortmund University, Emil-Figge-Str. 70, 44227 Dortmund, Germany
| | - Volker F. Wendisch
- Genetics of Prokaryotes, Faculty of Biology & CeBiTec, Bielefeld University, Universitätsstr. 25, 33615 Bielefeld, Germany
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9
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Nakayama Y. Corynebacterium glutamicum Mechanosensing: From Osmoregulation to L-Glutamate Secretion for the Avian Microbiota-Gut-Brain Axis. Microorganisms 2021; 9:201. [PMID: 33478007 PMCID: PMC7835871 DOI: 10.3390/microorganisms9010201] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 01/15/2021] [Accepted: 01/18/2021] [Indexed: 12/18/2022] Open
Abstract
After the discovery of Corynebacterium glutamicum from avian feces-contaminated soil, its enigmatic L-glutamate secretion by corynebacterial MscCG-type mechanosensitive channels has been utilized for industrial monosodium glutamate production. Bacterial mechanosensitive channels are activated directly by increased membrane tension upon hypoosmotic downshock; thus; the physiological significance of the corynebacterial L-glutamate secretion has been considered as adjusting turgor pressure by releasing cytoplasmic solutes. In this review, we present information that corynebacterial mechanosensitive channels have been evolutionally specialized as carriers to secrete L-glutamate into the surrounding environment in their habitats rather than osmotic safety valves. The lipid modulation activation of MscCG channels in L-glutamate production can be explained by the "Force-From-Lipids" and "Force-From-Tethers" mechanosensing paradigms and differs significantly from mechanical activation upon hypoosmotic shock. The review also provides information on the search for evidence that C. glutamicum was originally a gut bacterium in the avian host with the aim of understanding the physiological roles of corynebacterial mechanosensing. C. glutamicum is able to secrete L-glutamate by mechanosensitive channels in the gut microbiota and help the host brain function via the microbiota-gut-brain axis.
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Affiliation(s)
- Yoshitaka Nakayama
- Molecular Cardiology and Biophysics Division, Victor Chang Cardiac Research Institute, Darlinghurst, NSW 2010, Australia; ; Tel.: +61-2-9295-8744
- St Vincent’s Clinical School, Faculty of Medicine, The University of New South Wales, Darlinghurst, NSW 2010, Australia
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10
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Deng R, Gao X, Hou J, Lin D. Multi-omics analyses reveal molecular mechanisms for the antagonistic toxicity of carbon nanotubes and ciprofloxacin to Escherichia coli. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 726:138288. [PMID: 32305750 DOI: 10.1016/j.scitotenv.2020.138288] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Revised: 03/26/2020] [Accepted: 03/27/2020] [Indexed: 05/05/2023]
Abstract
With the increasing production and application, engineered nanomaterials (ENMs) are being discharged into the environment, where they can interact with co-existing contaminants, causing complicated joint toxicity to organisms that needs to be studied. The case study of ENMs-contaminant joint toxicity and the understanding of relative mechanisms are very insufficient, particularly the mechanisms of molecular interactions and governing processes. Herein, a typical ENMs, carbon nanotubes (CNTs, 0-60 mg/L), and a common antibiotic, ciprofloxacin (CIP, 0-900 mg/L), were selected as the analytes. Their joint toxicity to a model microbe Escherichia coli was specifically investigated via biochemical, transcriptomics, and metabolomics approaches. The result revealed an antagonistic effect on growth inhibition between CNTs and CIP. Mitigations in cell membrane disruption and oxidative stress were involved in the antagonistic action. CIP (48.8-244 mg/L) decreased the bioaccumulation of CNTs (7.2 mg/L) via reducing cell-surface hydrophobicity and hindering the bio-nano interaction, which could attenuate the toxicity of CNTs to bacteria. CNTs (7.2 and 14.4 mg/L) alleviated the disturbance of CIP (122 and 244 mg/L) to gene expressions especially related to nitrogen compound metabolism, oxidoreductase activity, and iron-sulfur protein maturation, probably through relieving the CIP-induced inhibition of DNA gyrase activity. Further, CNTs (7.2 and 14.4 mg/L) offset the impact of CIP (122 and 244 mg/L) on bacterial metabolome via the regulation of biosynthesis of unsaturated fatty acids and metabolisms of some amino acids and glutathione. The findings shed new light on the molecular mechanisms by which ENMs present joint effect on contaminant toxicity, and provide important information for risk assessments of CNTs and fluoroquinolones in the environment.
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Affiliation(s)
- Rui Deng
- Department of Environmental Science, Zhejiang University, Hangzhou 310058, China; Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Zhejiang University, Hangzhou 310058, China
| | - Xuan Gao
- Department of Environmental Science, Zhejiang University, Hangzhou 310058, China; Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Zhejiang University, Hangzhou 310058, China
| | - Jie Hou
- Department of Environmental Science, Zhejiang University, Hangzhou 310058, China; Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Zhejiang University, Hangzhou 310058, China
| | - Daohui Lin
- Department of Environmental Science, Zhejiang University, Hangzhou 310058, China; Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Zhejiang University, Hangzhou 310058, China.
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11
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Obrenovich M, Jaworski H, Tadimalla T, Mistry A, Sykes L, Perry G, Bonomo RA. The Role of the Microbiota-Gut-Brain Axis and Antibiotics in ALS and Neurodegenerative Diseases. Microorganisms 2020; 8:E784. [PMID: 32456229 PMCID: PMC7285349 DOI: 10.3390/microorganisms8050784] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Accepted: 05/14/2020] [Indexed: 12/12/2022] Open
Abstract
: The human gut hosts a wide and diverse ecosystem of microorganisms termed the microbiota, which line the walls of the digestive tract and colon where they co-metabolize digestible and indigestible food to contribute a plethora of biochemical compounds with diverse biological functions. The influence gut microbes have on neurological processes is largely yet unexplored. However, recent data regarding the so-called leaky gut, leaky brain syndrome suggests a potential link between the gut microbiota, inflammation and host co-metabolism that may affect neuropathology both locally and distally from sites where microorganisms are found. The focus of this manuscript is to draw connection between the microbiota-gut-brain (MGB) axis, antibiotics and the use of "BUGS AS DRUGS" for neurodegenerative diseases, their treatment, diagnoses and management and to compare the effect of current and past pharmaceuticals and antibiotics for alternative mechanisms of action for brain and neuronal disorders, such as Alzheimer disease (AD), Amyotrophic Lateral Sclerosis (ALS), mood disorders, schizophrenia, autism spectrum disorders and others. It is a paradigm shift to suggest these diseases can be largely affected by unknown aspects of the microbiota. Therefore, a future exists for applying microbial, chemobiotic and chemotherapeutic approaches to enhance translational and personalized medical outcomes. Microbial modifying applications, such as CRISPR technology and recombinant DNA technology, among others, echo a theme in shifting paradigms, which involve the gut microbiota (GM) and mycobiota and will lead to potential gut-driven treatments for refractory neurologic diseases.
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Affiliation(s)
- Mark Obrenovich
- Research Service, Louis Stokes Cleveland, Department of Veteran’s Affairs Medical Center, Cleveland, OH 44106, USA; (H.J.); (T.T.); (R.A.B.)
- Departments of Chemistry, Biochemistry, Pathology and Molecular Biology, Case Western Reserve University, Cleveland, OH 44106, USA
- The Gilgamesh Foundation for Medical Science and Research, Cleveland, OH 44116, USA
- Department of Medicinal and Biological Chemistry, College of Pharmacy and Pharmaceutical Sciences, University of Toledo, Toledo, OH 43606, USA
- Cleveland State University Departments of Chemistry and Engineering, Cleveland, OH 44115, USA;
| | - Hayden Jaworski
- Research Service, Louis Stokes Cleveland, Department of Veteran’s Affairs Medical Center, Cleveland, OH 44106, USA; (H.J.); (T.T.); (R.A.B.)
- Cleveland State University Departments of Chemistry and Engineering, Cleveland, OH 44115, USA;
| | - Tara Tadimalla
- Research Service, Louis Stokes Cleveland, Department of Veteran’s Affairs Medical Center, Cleveland, OH 44106, USA; (H.J.); (T.T.); (R.A.B.)
- Departments of Chemistry, Biochemistry, Pathology and Molecular Biology, Case Western Reserve University, Cleveland, OH 44106, USA
| | - Adil Mistry
- Cleveland State University Departments of Chemistry and Engineering, Cleveland, OH 44115, USA;
| | - Lorraine Sykes
- Department of Laboratory Medicine, Metro Health Medical Center, Cleveland, OH 44109, USA;
| | - George Perry
- Department of Biology University of Texas San Antonio, San Antonio, TX 78249, USA;
| | - Robert A. Bonomo
- Research Service, Louis Stokes Cleveland, Department of Veteran’s Affairs Medical Center, Cleveland, OH 44106, USA; (H.J.); (T.T.); (R.A.B.)
- Departments of Chemistry, Biochemistry, Pathology and Molecular Biology, Case Western Reserve University, Cleveland, OH 44106, USA
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12
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Mindt M, Walter T, Kugler P, Wendisch VF. Microbial Engineering for Production of N-Functionalized Amino Acids and Amines. Biotechnol J 2020; 15:e1900451. [PMID: 32170807 DOI: 10.1002/biot.201900451] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2019] [Revised: 03/04/2020] [Indexed: 01/04/2023]
Abstract
N-functionalized amines play important roles in nature and occur, for example, in the antibiotic vancomycin, the immunosuppressant cyclosporine, the cytostatic actinomycin, the siderophore aerobactin, the cyanogenic glucoside linamarin, and the polyamine spermidine. In the pharmaceutical and fine-chemical industries N-functionalized amines are used as building blocks for the preparation of bioactive molecules. Processes based on fermentation and on enzyme catalysis have been developed to provide sustainable manufacturing routes to N-alkylated, N-hydroxylated, N-acylated, or other N-functionalized amines including polyamines. Metabolic engineering for provision of precursor metabolites is combined with heterologous N-functionalizing enzymes such as imine or ketimine reductases, opine or amino acid dehydrogenases, N-hydroxylases, N-acyltransferase, or polyamine synthetases. Recent progress and applications of fermentative processes using metabolically engineered bacteria and yeasts along with the employed enzymes are reviewed and the perspectives on developing new fermentative processes based on insight from enzyme catalysis are discussed.
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Affiliation(s)
- Melanie Mindt
- Genetics of Prokaryotes, Biology and CeBiTec, Bielefeld University, Bielefeld, 33615, Germany.,BU Bioscience, Wageningen University and Research, Wageningen, 6708 PB, The Netherlands
| | - Tatjana Walter
- Genetics of Prokaryotes, Biology and CeBiTec, Bielefeld University, Bielefeld, 33615, Germany
| | - Pierre Kugler
- Genetics of Prokaryotes, Biology and CeBiTec, Bielefeld University, Bielefeld, 33615, Germany
| | - Volker F Wendisch
- Genetics of Prokaryotes, Biology and CeBiTec, Bielefeld University, Bielefeld, 33615, Germany
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13
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Schultenkämper K, Brito LF, Wendisch VF. Impact of CRISPR interference on strain development in biotechnology. Biotechnol Appl Biochem 2020; 67:7-21. [DOI: 10.1002/bab.1901] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Accepted: 02/13/2020] [Indexed: 12/17/2022]
Affiliation(s)
| | - Luciana F. Brito
- Department of Biotechnology and Food ScienceNTNUNorwegian University of Science and Technology Trondheim Norway
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14
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Wendisch VF. Metabolic engineering advances and prospects for amino acid production. Metab Eng 2019; 58:17-34. [PMID: 30940506 DOI: 10.1016/j.ymben.2019.03.008] [Citation(s) in RCA: 147] [Impact Index Per Article: 29.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2019] [Revised: 03/26/2019] [Accepted: 03/26/2019] [Indexed: 11/18/2022]
Abstract
Amino acid fermentation is one of the major pillars of industrial biotechnology. The multi-billion USD amino acid market is rising steadily and is diversifying. Metabolic engineering is no longer focused solely on strain development for the bulk amino acids L-glutamate and L-lysine that are produced at the million-ton scale, but targets specialty amino acids. These demands are met by the development and application of new metabolic engineering tools including CRISPR and biosensor technologies as well as production processes by enabling a flexible feedstock concept, co-production and co-cultivation schemes. Metabolic engineering advances are exemplified for specialty proteinogenic amino acids, cyclic amino acids, omega-amino acids, and amino acids functionalized by hydroxylation, halogenation and N-methylation.
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Affiliation(s)
- Volker F Wendisch
- Genetics of Prokaryotes, Faculty of Biology and Center for Biotechnology (CeBiTec), Bielefeld University, Bielefeld, Germany.
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15
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Pérez-García F, Brito LF, Wendisch VF. Function of L-Pipecolic Acid as Compatible Solute in Corynebacterium glutamicum as Basis for Its Production Under Hyperosmolar Conditions. Front Microbiol 2019; 10:340. [PMID: 30858843 PMCID: PMC6397837 DOI: 10.3389/fmicb.2019.00340] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Accepted: 02/08/2019] [Indexed: 12/20/2022] Open
Abstract
Pipecolic acid or L-PA is a cyclic amino acid derived from L-lysine which has gained interest in the recent years within the pharmaceutical and chemical industries. L-PA can be produced efficiently using recombinant Corynebacterium glutamicum strains by expanding the natural L-lysine biosynthetic pathway. L-PA is a six-membered ring homolog of the five-membered ring amino acid L-proline, which serves as compatible solute in C. glutamicum. Here, we show that de novo synthesized or externally added L-PA partially is beneficial for growth under hyper-osmotic stress conditions. C. glutamicum cells accumulated L-PA under elevated osmotic pressure and released it after an osmotic down shock. In the absence of the mechanosensitive channel YggB intracellular L-PA concentrations increased and its release after osmotic down shock was slower. The proline permease ProP was identified as a candidate L-PA uptake system since RNAseq analysis revealed increased proP RNA levels upon L-PA production. Under hyper-osmotic conditions, a ΔproP strain showed similar growth behavior than the parent strain when L-proline was added externally. By contrast, the growth impairment of the ΔproP strain under hyper-osmotic conditions could not be alleviated by addition of L-PA unless proP was expressed from a plasmid. This is commensurate with the view that L-proline can be imported into the C. glutamicum cell by ProP and other transporters such as EctP and PutP, while ProP appears of major importance for L-PA uptake under hyper-osmotic stress conditions.
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Affiliation(s)
- Fernando Pérez-García
- Genetics of Prokaryotes, Faculty of Biology - CeBiTec, Bielefeld University, Bielefeld, Germany
| | - Luciana F Brito
- Genetics of Prokaryotes, Faculty of Biology - CeBiTec, Bielefeld University, Bielefeld, Germany
| | - Volker F Wendisch
- Genetics of Prokaryotes, Faculty of Biology - CeBiTec, Bielefeld University, Bielefeld, Germany
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16
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Koduru L, Lakshmanan M, Lee DY. In silico model-guided identification of transcriptional regulator targets for efficient strain design. Microb Cell Fact 2018; 17:167. [PMID: 30359263 PMCID: PMC6201637 DOI: 10.1186/s12934-018-1015-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Accepted: 10/20/2018] [Indexed: 01/13/2023] Open
Abstract
BACKGROUND Cellular metabolism is tightly regulated by hard-wired multiple layers of biological processes to achieve robust and homeostatic states given the limited resources. As a result, even the most intuitive enzyme-centric metabolic engineering endeavours through the up-/down-regulation of multiple genes in biochemical pathways often deliver insignificant improvements in the product yield. In this regard, targeted engineering of transcriptional regulators (TRs) that control several metabolic functions in modular patterns is an interesting strategy. However, only a handful of in silico model-added techniques are available for identifying the TR manipulation candidates, thus limiting its strain design application. RESULTS We developed hierarchical-Beneficial Regulatory Targeting (h-BeReTa) which employs a genome-scale metabolic model and transcriptional regulatory network (TRN) to identify the relevant TR targets suitable for strain improvement. We then applied this method to industrially relevant metabolites and cell factory hosts, Escherichia coli and Corynebacterium glutamicum. h-BeReTa suggested several promising TR targets, many of which have been validated through literature evidences. h-BeReTa considers the hierarchy of TRs in the TRN and also accounts for alternative metabolic pathways which may divert flux away from the product while identifying suitable metabolic fluxes, thereby performing superior in terms of global TR target identification. CONCLUSIONS In silico model-guided strain design framework, h-BeReTa, was presented for identifying transcriptional regulator targets. Its efficacy and applicability to microbial cell factories were successfully demonstrated via case studies involving two cell factory hosts, as such suggesting several intuitive targets for overproducing various value-added compounds.
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Affiliation(s)
- Lokanand Koduru
- Department of Chemical and Biomolecular Engineering, National University of Singapore, 4 Engineering Drive 4, Singapore, 117576, Singapore
| | - Meiyappan Lakshmanan
- Bioprocessing Technology Institute, Agency for Science, Technology and Research (A*STAR), 20 Biopolis Way, #06-01, Centros, Singapore, 138668, Singapore
| | - Dong-Yup Lee
- Bioprocessing Technology Institute, Agency for Science, Technology and Research (A*STAR), 20 Biopolis Way, #06-01, Centros, Singapore, 138668, Singapore.
- School of Chemical Engineering, Sungkyunkwan University, 2066, Seobu-ro, Jangan-gu, Suwon, Gyeonggi-do, 16419, Republic of Korea.
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17
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Zhang B, Ren LQ, Yu M, Zhou Y, Ye BC. Enhanced l-ornithine production by systematic manipulation of l-ornithine metabolism in engineered Corynebacterium glutamicum S9114. BIORESOURCE TECHNOLOGY 2018; 250:60-68. [PMID: 29153651 DOI: 10.1016/j.biortech.2017.11.017] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2017] [Revised: 11/05/2017] [Accepted: 11/06/2017] [Indexed: 06/07/2023]
Abstract
l-Ornithine is a non-protein amino acid with extensive applications in medicine and the food industry. Currently, l-ornithine is produced by microbial fermentation; however, this process needs to be further improved in terms of l-ornithine productivity and cost reduction. In this study, overexpression of LysE was observed to increase l-ornithine production in engineered Corynebacterium glutamicum S9114. To overcome the drawbacks of using a plasmid to express LysE, Ptac, a strong promoter, was inserted in the upstream region of lysE on the chromosome. This strain was further engineered by attenuating the expression of ncgl2228 and proB, and enhancing the expression of gdh and argCJBD. Combination of those targets resulted in l-ornithine production at a titer of 25 g/L, which was 63.4% higher than that produced by the original strain (15.3 g/L). These results demonstrated the positive effects of overexpressing LysE on l-ornithine production and provided novel targets for developing l-ornithine-producing C. glutamicum strains.
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Affiliation(s)
- Bin Zhang
- Laboratory of Biosystems and Microanalysis, State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Li-Quan Ren
- Laboratory of Biosystems and Microanalysis, State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Miao Yu
- Laboratory of Biosystems and Microanalysis, State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Ying Zhou
- Laboratory of Biosystems and Microanalysis, State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Bang-Ce Ye
- Laboratory of Biosystems and Microanalysis, State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China; Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, College of Pharmaceutical Sciences, Zhejiang University of Technology, Hangzhou 310014, Zhejiang, China.
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18
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Adaptive laboratory evolution of Corynebacterium glutamicum towards higher growth rates on glucose minimal medium. Sci Rep 2017; 7:16780. [PMID: 29196644 PMCID: PMC5711897 DOI: 10.1038/s41598-017-17014-9] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Accepted: 11/17/2017] [Indexed: 12/18/2022] Open
Abstract
In this work, we performed a comparative adaptive laboratory evolution experiment of the important biotechnological platform strain Corynebacterium glutamicum ATCC 13032 and its prophage-free variant MB001 towards improved growth rates on glucose minimal medium. Both strains displayed a comparable adaptation behavior and no significant differences in genomic rearrangements and mutation frequencies. Remarkably, a significant fitness leap by about 20% was observed for both strains already after 100 generations. Isolated top clones (UBw and UBm) showed an about 26% increased growth rate on glucose minimal medium. Genome sequencing of evolved clones and populations resulted in the identification of key mutations in pyk (pyruvate kinase), fruK (1-phosphofructokinase) and corA encoding a Mg2+ importer. The reintegration of selected pyk and fruK mutations resulted in an increased glucose consumption rate and ptsG expression causative for the accelerated growth on glucose minimal medium, whereas corA mutations improved growth under Mg2+ limiting conditions. Overall, this study resulted in the identification of causative key mutations improving the growth of C. glutamicum on glucose. These identified mutational hot spots as well as the two evolved top strains, UBw and UBm, represent promising targets for future metabolic engineering approaches.
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19
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Jorge JMP, Nguyen AQD, Pérez-García F, Kind S, Wendisch VF. Improved fermentative production of gamma-aminobutyric acid via the putrescine route: Systems metabolic engineering for production from glucose, amino sugars, and xylose. Biotechnol Bioeng 2016; 114:862-873. [PMID: 27800627 DOI: 10.1002/bit.26211] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Revised: 10/04/2016] [Accepted: 10/28/2016] [Indexed: 11/07/2022]
Abstract
Gamma-aminobutyric acid (GABA) is a non-protein amino acid widespread in Nature. Among the various uses of GABA, its lactam form 2-pyrrolidone can be chemically converted to the biodegradable plastic polyamide-4. In metabolism, GABA can be synthesized either by decarboxylation of l-glutamate or by a pathway that starts with the transamination of putrescine. Fermentative production of GABA from glucose by recombinant Corynebacterium glutamicum has been described via both routes. Putrescine-based GABA production was characterized by accumulation of by-products such as N-acetyl-putrescine. Their formation was abolished by deletion of the spermi(di)ne N-acetyl-transferase gene snaA. To improve provision of l-glutamate as precursor 2-oxoglutarate dehydrogenase activity was reduced by changing the translational start codon of the chromosomal gene for 2-oxoglutarate dehydrogenase subunit E1o to the less preferred TTG and by maintaining the inhibitory protein OdhI in its inhibitory form by changing amino acid residue 15 from threonine to alanine. Putrescine-based GABA production by the strains described here led to GABA titers up to 63.2 g L-1 in fed-batch cultivation at maximum volumetric productivities up to 1.34 g L-1 h-1 , the highest volumetric productivity for fermentative GABA production reported to date. Moreover, GABA production from the carbon sources xylose, glucosamine, and N-acetyl-glucosamine that do not have competing uses in the food or feed industries was established. Biotechnol. Bioeng. 2017;114: 862-873. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- João M P Jorge
- Faculty of Biology and CeBiTec, Genetics of Prokaryotes, Bielefeld University, Universitätsstr. 25, Bielefeld 33615, Germany
| | - Anh Q D Nguyen
- Faculty of Biology and CeBiTec, Genetics of Prokaryotes, Bielefeld University, Universitätsstr. 25, Bielefeld 33615, Germany.,evocatal GmbH, Monheim, Germany
| | - Fernando Pérez-García
- Faculty of Biology and CeBiTec, Genetics of Prokaryotes, Bielefeld University, Universitätsstr. 25, Bielefeld 33615, Germany
| | | | - Volker F Wendisch
- Faculty of Biology and CeBiTec, Genetics of Prokaryotes, Bielefeld University, Universitätsstr. 25, Bielefeld 33615, Germany
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