1
|
Ray D, Anand U, Jha NK, Korzeniewska E, Bontempi E, Proćków J, Dey A. The soil bacterium, Corynebacterium glutamicum, from biosynthesis of value-added products to bioremediation: A master of many trades. ENVIRONMENTAL RESEARCH 2022; 213:113622. [PMID: 35710026 DOI: 10.1016/j.envres.2022.113622] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 05/05/2022] [Accepted: 06/03/2022] [Indexed: 06/15/2023]
Abstract
Ever since its discovery in 1957, Corynebacterium glutamicum has become a well-established industrial strain and is known for its massive capability of producing various amino acids (like L-lysine and L-glutamate) and other value-added chemicals. With the rising demand for these bio-based products, the revelation of the whole genome sequences of the wild type strains, and the astounding advancements made in the fields of metabolic engineering and systems biology, our perspective of C. glutamicum has been revolutionized and has expanded our understanding of its strain development. With these advancements, a new era for C. glutamicum supremacy in the field of industrial biotechnology began. This led to remarkable progress in the enhancement of tailor-made over-producing strains and further development of the substrate spectrum of the bacterium, to easily accessible, economical, and renewable resources. C. glutamicum has also been metabolically engineered and used in the degradation/assimilation of highly toxic and ubiquitous environmental contaminant, arsenic, present in water or soil. Here, we review the history, current knowledge, progress, achievements, and future trends relating to the versatile metabolic factory, C. glutamicum. This review paper is devoted to C. glutamicum which is one of the leading industrial microbes, and one of the most promising and versatile candidates to be developed. It can be used not only as a platform microorganism to produce different value-added chemicals and recombinant proteins, but also as a tool for bioremediation, allowing to enhance specific properties, for example in situ bioremediation.
Collapse
Affiliation(s)
- Durga Ray
- Department of Microbiology, St. Aloysius' College, Jabalpur, Madhya Pradesh, 482001, India.
| | - Uttpal Anand
- Department of Life Sciences, Ben-Gurion University of the Negev, Beer-Sheva, 84105, Israel
| | - Niraj Kumar Jha
- Department of Biotechnology, School of Engineering & Technology, Sharda University, Greater Noida, 201310, Uttar Pradesh, India; Department of Biotechnology Engineering and Food Technology, Chandigarh University, Mohali, 140413, Punjab, India; Department of Biotechnology, School of Applied & Life Sciences, Uttaranchal University, Dehradun 248007, Uttarakhand, India
| | - Ewa Korzeniewska
- Department of Water Protection Engineering and Environmental Microbiology, The Faculty of Geoengineering, University of Warmia and Mazury in Olsztyn, Prawocheńskiego 1 Str., 10-719, Olsztyn, Poland
| | - Elza Bontempi
- INSTM and Chemistry for Technologies Laboratory, Department of Mechanical and Industrial Engineering, University of Brescia, Via Branze, 38, 25123, Brescia, Italy
| | - Jarosław Proćków
- Department of Plant Biology, Institute of Environmental Biology, Wrocław University of Environmental and Life Sciences, Kożuchowska 5b, 51-631, Wrocław, Poland.
| | - Abhijit Dey
- Department of Life Sciences, Presidency University, 86/1 College Street, Kolkata, 700073, West Bengal, India.
| |
Collapse
|
2
|
Recent progress in metabolic engineering of Corynebacterium glutamicum for the production of C4, C5, and C6 chemicals. KOREAN J CHEM ENG 2021. [DOI: 10.1007/s11814-021-0788-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
|
3
|
Siziya IN, Kim YS, Seo DH. Whole cell biosynthesis of luteolin glycosides by engineered Corynebacterium glutamicum harboring the amylosucrase gene. FOOD AND BIOPRODUCTS PROCESSING 2021. [DOI: 10.1016/j.fbp.2021.03.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
|
4
|
Prell C, Burgardt A, Meyer F, Wendisch VF. Fermentative Production of l-2-Hydroxyglutarate by Engineered Corynebacterium glutamicum via Pathway Extension of l-Lysine Biosynthesis. Front Bioeng Biotechnol 2021; 8:630476. [PMID: 33585425 PMCID: PMC7873477 DOI: 10.3389/fbioe.2020.630476] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Accepted: 12/24/2020] [Indexed: 11/16/2022] Open
Abstract
l-2-hydroxyglutarate (l-2HG) is a trifunctional building block and highly attractive for the chemical and pharmaceutical industries. The natural l-lysine biosynthesis pathway of the amino acid producer Corynebacterium glutamicum was extended for the fermentative production of l-2HG. Since l-2HG is not native to the metabolism of C. glutamicum metabolic engineering of a genome-streamlined l-lysine overproducing strain was required to enable the conversion of l-lysine to l-2HG in a six-step synthetic pathway. To this end, l-lysine decarboxylase was cascaded with two transamination reactions, two NAD(P)-dependent oxidation reactions and the terminal 2-oxoglutarate-dependent glutarate hydroxylase. Of three sources for glutarate hydroxylase the metalloenzyme CsiD from Pseudomonas putida supported l-2HG production to the highest titers. Genetic experiments suggested a role of succinate exporter SucE for export of l-2HG and improving expression of its gene by chromosomal exchange of its native promoter improved l-2HG production. The availability of Fe2+ as cofactor of CsiD was identified as a major bottleneck in the conversion of glutarate to l-2HG. As consequence of strain engineering and media adaptation product titers of 34 ± 0 mM were obtained in a microcultivation system. The glucose-based process was stable in 2 L bioreactor cultivations and a l-2HG titer of 3.5 g L−1 was obtained at the higher of two tested aeration levels. Production of l-2HG from a sidestream of the starch industry as renewable substrate was demonstrated. To the best of our knowledge, this study is the first description of fermentative production of l-2HG, a monomeric precursor used in electrochromic polyamides, to cross-link polyamides or to increase their biodegradability.
Collapse
Affiliation(s)
- Carina Prell
- Genetics of Prokaryotes, Faculty of Biology, Center for Biotechnology (CeBiTec), Bielefeld University, Bielefeld, Germany
| | - Arthur Burgardt
- Genetics of Prokaryotes, Faculty of Biology, Center for Biotechnology (CeBiTec), Bielefeld University, Bielefeld, Germany
| | - Florian Meyer
- Genetics of Prokaryotes, Faculty of Biology, Center for Biotechnology (CeBiTec), Bielefeld University, Bielefeld, Germany
| | - Volker F Wendisch
- Genetics of Prokaryotes, Faculty of Biology, Center for Biotechnology (CeBiTec), Bielefeld University, Bielefeld, Germany
| |
Collapse
|
5
|
Cascaded valorization of seaweed using microbial cell factories. Curr Opin Biotechnol 2020; 65:102-113. [DOI: 10.1016/j.copbio.2020.02.008] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Revised: 02/14/2020] [Accepted: 02/17/2020] [Indexed: 11/17/2022]
|
6
|
Haas T, Graf M, Nieß A, Busche T, Kalinowski J, Blombach B, Takors R. Identifying the Growth Modulon of Corynebacterium glutamicum. Front Microbiol 2019; 10:974. [PMID: 31134020 PMCID: PMC6517550 DOI: 10.3389/fmicb.2019.00974] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Accepted: 04/18/2019] [Indexed: 12/16/2022] Open
Abstract
The growth rate (μ) of industrially relevant microbes, such as Corynebacterium glutamicum, is a fundamental property that indicates its production capacity. Therefore, understanding the mechanism underlying the growth rate is imperative for improving productivity and performance through metabolic engineering. Despite recent progress in the understanding of global regulatory interactions, knowledge of mechanisms directing cell growth remains fragmented and incomplete. The current study investigated RNA-Seq data of three growth rate transitions, induced by different pre-culture conditions, in order to identify transcriptomic changes corresponding to increasing growth rates. These transitions took place in minimal medium and ranged from 0.02 to 0.4 h-1 μ. This study enabled the identification of 447 genes as components of the growth modulon. Enrichment of genes within the growth modulon revealed 10 regulons exhibiting a significant effect over growth rate transition. In summary, central metabolism was observed to be regulated by a combination of metabolic and transcriptional activities orchestrating control over glycolysis, pentose phosphate pathway, and the tricarboxylic acid cycle. Additionally, major responses to changes in the growth rate were linked to iron uptake and carbon metabolism. In particular, genes encoding glycolytic enzymes and the glucose uptake system showed a positive correlation with the growth rate.
Collapse
Affiliation(s)
- Thorsten Haas
- Institute of Biochemical Engineering, University of Stuttgart, Stuttgart, Germany
| | - Michaela Graf
- Institute of Biochemical Engineering, University of Stuttgart, Stuttgart, Germany
| | - Alexander Nieß
- Institute of Biochemical Engineering, University of Stuttgart, Stuttgart, Germany
| | - Tobias Busche
- Center for Biotechnology (CeBiTec), Bielefeld University, Bielefeld, Germany.,Institute for Biology-Microbiology, Freie Universität Berlin, Berlin, Germany
| | - Jörn Kalinowski
- Center for Biotechnology (CeBiTec), Bielefeld University, Bielefeld, Germany
| | - Bastian Blombach
- Institute of Biochemical Engineering, University of Stuttgart, Stuttgart, Germany.,Microbial Biotechnology, Campus Straubing for Biotechnology and Sustainability, Technical University of Munich, Straubing, Germany
| | - Ralf Takors
- Institute of Biochemical Engineering, University of Stuttgart, Stuttgart, Germany
| |
Collapse
|
7
|
Microbial Production of Amino Acid-Related Compounds. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2017; 159:255-269. [PMID: 27872963 DOI: 10.1007/10_2016_34] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Corynebacterium glutamicum is the workhorse of the production of proteinogenic amino acids used in food and feed biotechnology. After more than 50 years of safe amino acid production, C. glutamicum has recently also been engineered for the production of amino acid-derived compounds, which find various applications, e.g., as synthons for the chemical industry in several markets including the polymer market. The amino acid-derived compounds such as non-proteinogenic ω-amino acids, α,ω-diamines, and cyclic or hydroxylated amino acids have similar carbon backbones and functional groups as their amino acid precursors. Decarboxylation of amino acids may yield ω-amino acids such as β-alanine, γ-aminobutyrate, and δ-aminovalerate as well as α,ω-diamines such as putrescine and cadaverine. Since transamination is the final step in several amino acid biosynthesis pathways, 2-keto acids as immediate amino acid precursors are also amenable to production using recombinant C. glutamicum strains. Approaches for metabolic engineering of C. glutamicum for production of amino acid-derived compounds will be described, and where applicable, production from alternative carbon sources or use of genome streamline will be referred to. The excellent large-scale fermentation experience with C. glutamicum offers the possibility that these amino acid-derived speciality products may enter large-volume markets.
Collapse
|
8
|
Podleśny M, Jarocki P, Wyrostek J, Czernecki T, Kucharska J, Nowak A, Targoński Z. Enterobacter sp. LU1 as a novel succinic acid producer - co-utilization of glycerol and lactose. Microb Biotechnol 2017; 10:492-501. [PMID: 27910262 PMCID: PMC5328818 DOI: 10.1111/1751-7915.12458] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Revised: 10/05/2016] [Accepted: 10/22/2016] [Indexed: 11/28/2022] Open
Abstract
Succinic acid is an important C4-building chemical platform for many applications. A novel succinic acid-producing bacterial strain was isolated from goat rumen. Phylogenetic analysis based on the 16S rRNA sequence and physiological analysis indicated that the strain belongs to the genus Enterobacter. This is the first report of a wild bacterial strain from the genus Enterobacter that is capable of efficient succinic acid production. Co-fermentation of glycerol and lactose significantly improved glycerol utilization under anaerobic conditions, debottlenecking the utilization pathway of this valuable biodiesel waste product. Succinic acid production reached 35 g l-1 when Enterobacter sp. LU1 was cultured in medium containing 50 g l-1 of glycerol and 25 g l-1 of lactose as carbon sources.
Collapse
Affiliation(s)
- Marcin Podleśny
- Department of Biotechnology, Human Nutrition and Food CommoditiesLublin University of Life Sciences8 SkromnaLublin20‐704Poland
| | - Piotr Jarocki
- Department of Biotechnology, Human Nutrition and Food CommoditiesLublin University of Life Sciences8 SkromnaLublin20‐704Poland
| | - Jakub Wyrostek
- Department of Analysis and Food Quality AssessmentLublin University of Life Sciences8 SkromnaLublin20‐704Poland
| | - Tomasz Czernecki
- Department of Biotechnology, Human Nutrition and Food CommoditiesLublin University of Life Sciences8 SkromnaLublin20‐704Poland
| | - Jagoda Kucharska
- Department of Biotechnology, Human Nutrition and Food CommoditiesLublin University of Life Sciences8 SkromnaLublin20‐704Poland
| | - Anna Nowak
- Department of Biotechnology, Human Nutrition and Food CommoditiesLublin University of Life Sciences8 SkromnaLublin20‐704Poland
| | - Zdzisław Targoński
- Department of Biotechnology, Human Nutrition and Food CommoditiesLublin University of Life Sciences8 SkromnaLublin20‐704Poland
| |
Collapse
|
9
|
Affiliation(s)
- Volker F. Wendisch
- Bielefeld University; Genetics of Prokaryotes, Faculty of Biology and CeBiTec; Postfach 100131 33501 Bielefeld Germany
| |
Collapse
|
10
|
Kou F, Zhao J, Liu J, Shen J, Ye Q, Zheng P, Li Z, Sun J, Ma Y. Characterization of a new lysine decarboxylase from Aliivibrio salmonicida for cadaverine production at alkaline pH. ACTA ACUST UNITED AC 2016. [DOI: 10.1016/j.molcatb.2016.11.023] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
|
11
|
Wendisch VF, Brito LF, Gil Lopez M, Hennig G, Pfeifenschneider J, Sgobba E, Veldmann KH. The flexible feedstock concept in Industrial Biotechnology: Metabolic engineering of Escherichia coli, Corynebacterium glutamicum, Pseudomonas, Bacillus and yeast strains for access to alternative carbon sources. J Biotechnol 2016; 234:139-157. [DOI: 10.1016/j.jbiotec.2016.07.022] [Citation(s) in RCA: 79] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2016] [Revised: 07/25/2016] [Accepted: 07/28/2016] [Indexed: 11/28/2022]
|
12
|
Christopher M, Anusree M, Mathew AK, Nampoothiri KM, Sukumaran RK, Pandey A. Detoxification of acidic biorefinery waste liquor for production of high value amino acid. BIORESOURCE TECHNOLOGY 2016; 213:270-275. [PMID: 26996259 DOI: 10.1016/j.biortech.2016.03.054] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2016] [Revised: 03/08/2016] [Accepted: 03/10/2016] [Indexed: 05/14/2023]
Abstract
The current study evaluates the detoxification of acid pretreatment liquor (APL) using adsorbent (ADS 400 & ADS 800) or ion-exchange (A-27MP & A-72MP) resins and its potential for amino acid production. The APL is generated as a by-product from the pretreatment of lignocellulosic biomass and is rich monomeric sugars as well as sugar degradation products (fermentation inhibitors) such as furfural and hydroxymethyl furfural (HMF). Of the four resins compared, ADS 800 removed approximately 85% and 60% of furfural and HMF, respectively. ADS 800 could be reused for up to six cycles after regeneration without losing its adsorption properties. The study was further extended by assessing the fermentability of detoxified APL for l-lysine production using wild and mutant strains of Corynebacterium glutamicum. The detoxified APL was superior to APL for l-lysine production.
Collapse
Affiliation(s)
- Meera Christopher
- Centre for Biofuels and Biotechnology Division, CSIR-National Institute for Interdisciplinary Science and Technology, Industrial Estate P.O., Thiruvananthapuram 695019, India
| | - Murali Anusree
- Centre for Biofuels and Biotechnology Division, CSIR-National Institute for Interdisciplinary Science and Technology, Industrial Estate P.O., Thiruvananthapuram 695019, India
| | - Anil K Mathew
- Centre for Biofuels and Biotechnology Division, CSIR-National Institute for Interdisciplinary Science and Technology, Industrial Estate P.O., Thiruvananthapuram 695019, India.
| | - K Madhavan Nampoothiri
- Centre for Biofuels and Biotechnology Division, CSIR-National Institute for Interdisciplinary Science and Technology, Industrial Estate P.O., Thiruvananthapuram 695019, India
| | - Rajeev Kumar Sukumaran
- Centre for Biofuels and Biotechnology Division, CSIR-National Institute for Interdisciplinary Science and Technology, Industrial Estate P.O., Thiruvananthapuram 695019, India
| | - Ashok Pandey
- Centre for Biofuels and Biotechnology Division, CSIR-National Institute for Interdisciplinary Science and Technology, Industrial Estate P.O., Thiruvananthapuram 695019, India
| |
Collapse
|
13
|
Transcription of Sialic Acid Catabolism Genes in Corynebacterium glutamicum Is Subject to Catabolite Repression and Control by the Transcriptional Repressor NanR. J Bacteriol 2016; 198:2204-18. [PMID: 27274030 DOI: 10.1128/jb.00820-15] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2015] [Accepted: 05/18/2016] [Indexed: 12/31/2022] Open
Abstract
UNLABELLED Corynebacterium glutamicum metabolizes sialic acid (Neu5Ac) to fructose-6-phosphate (fructose-6P) via the consecutive activity of the sialic acid importer SiaEFGI, N-acetylneuraminic acid lyase (NanA), N-acetylmannosamine kinase (NanK), N-acetylmannosamine-6P epimerase (NanE), N-acetylglucosamine-6P deacetylase (NagA), and glucosamine-6P deaminase (NagB). Within the cluster of the three operons nagAB, nanAKE, and siaEFGI for Neu5Ac utilization a fourth operon is present, which comprises cg2936, encoding a GntR-type transcriptional regulator, here named NanR. Microarray studies and reporter gene assays showed that nagAB, nanAKE, siaEFGI, and nanR are repressed in wild-type (WT) C. glutamicum but highly induced in a ΔnanR C. glutamicum mutant. Purified NanR was found to specifically bind to the nucleotide motifs A[AC]G[CT][AC]TGATGTC[AT][TG]ATGT[AC]TA located within the nagA-nanA and nanR-sialA intergenic regions. Binding of NanR to promoter regions was abolished in the presence of the Neu5Ac metabolism intermediates GlcNAc-6P and N-acetylmannosamine-6-phosphate (ManNAc-6P). We observed consecutive utilization of glucose and Neu5Ac as well as fructose and Neu5Ac by WT C. glutamicum, whereas the deletion mutant C. glutamicum ΔnanR simultaneously consumed these sugars. Increased reporter gene activities for nagAB, nanAKE, and nanR were observed in cultivations of WT C. glutamicum with Neu5Ac as the sole substrate compared to cultivations when fructose was present. Taken together, our findings show that Neu5Ac metabolism in C. glutamicum is subject to catabolite repression, which involves control by the repressor NanR. IMPORTANCE Neu5Ac utilization is currently regarded as a common trait of both pathogenic and commensal bacteria. Interestingly, the nonpathogenic soil bacterium C. glutamicum efficiently utilizes Neu5Ac as a substrate for growth. Expression of genes for Neu5Ac utilization in C. glutamicum is here shown to depend on the transcriptional regulator NanR, which is the first GntR-type regulator of Neu5Ac metabolism not to use Neu5Ac as effector but relies instead on the inducers GlcNAc-6P and ManNAc-6P. The identification of conserved NanR-binding sites in intergenic regions within the operons for Neu5Ac utilization in pathogenic Corynebacterium species indicates that the mechanism for the control of Neu5Ac catabolism in C. glutamicum by NanR as described in this work is probably conserved within this genus.
Collapse
|
14
|
Dhar KS, Wendisch VF, Nampoothiri KM. Engineering of Corynebacterium glutamicum for xylitol production from lignocellulosic pentose sugars. J Biotechnol 2016; 230:63-71. [DOI: 10.1016/j.jbiotec.2016.05.011] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2016] [Revised: 04/20/2016] [Accepted: 05/06/2016] [Indexed: 12/31/2022]
|
15
|
Heider SAE, Wendisch VF. Engineering microbial cell factories: Metabolic engineering ofCorynebacterium glutamicumwith a focus on non-natural products. Biotechnol J 2015. [DOI: 10.1002/biot.201400590] [Citation(s) in RCA: 93] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
|
16
|
Nguyen AQD, Schneider J, Reddy GK, Wendisch VF. Fermentative production of the diamine putrescine: system metabolic engineering of corynebacterium glutamicum. Metabolites 2015; 5:211-31. [PMID: 25919117 PMCID: PMC4495370 DOI: 10.3390/metabo5020211] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2015] [Revised: 04/08/2015] [Accepted: 04/13/2015] [Indexed: 11/16/2022] Open
Abstract
Corynebacterium glutamicum shows great potential for the production of the glutamate-derived diamine putrescine, a monomeric compound of polyamides. A genome-scale stoichiometric model of a C. glutamicum strain with reduced ornithine transcarbamoylase activity, derepressed arginine biosynthesis, and an anabolic plasmid-addiction system for heterologous expression of E. coli ornithine decarboxylase gene speC was investigated by flux balance analysis with respect to its putrescine production potential. Based on these simulations, enhancing glycolysis and anaplerosis by plasmid-borne overexpression of the genes for glyceraldehyde 3-phosphate dehydrogenase and pyruvate carboxylase as well as reducing 2-oxoglutarate dehydrogenase activity were chosen as targets for metabolic engineering. Changing the translational start codon of the chromosomal gene for 2-oxoglutarate dehydrogenase subunit E1o to the less preferred TTG and changing threonine 15 of OdhI to alanine reduced 2-oxoglutarate dehydrogenase activity about five fold and improved putrescine titers by 28%. Additional engineering steps improved further putrescine production with the largest contributions from preventing the formation of the by-product N-acetylputrescine by deletion of spermi(di)ne N-acetyltransferase gene snaA and from overexpression of the gene for a feedback-resistant N-acetylglutamate kinase variant. The resulting C. glutamicum strain NA6 obtained by systems metabolic engineering accumulated two fold more putrescine than the base strain, i.e., 58.1 ± 0.2 mM, and showed a specific productivity of 0.045 g·g-1·h-1 and a yield on glucose of 0.26 g·g-1.
Collapse
Affiliation(s)
- Anh Q D Nguyen
- Chair of Genetics of Prokaryotes, Faculty of Biology & CeBiTec, Bielefeld University, Universitätsstr. 25, 33615 Bielefeld, Germany.
| | - Jens Schneider
- Chair of Genetics of Prokaryotes, Faculty of Biology & CeBiTec, Bielefeld University, Universitätsstr. 25, 33615 Bielefeld, Germany.
| | - Gajendar Komati Reddy
- Chair of Genetics of Prokaryotes, Faculty of Biology & CeBiTec, Bielefeld University, Universitätsstr. 25, 33615 Bielefeld, Germany.
| | - Volker F Wendisch
- Chair of Genetics of Prokaryotes, Faculty of Biology & CeBiTec, Bielefeld University, Universitätsstr. 25, 33615 Bielefeld, Germany.
| |
Collapse
|