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Shi J, Deng C, Zhang C, Quan S, Fan L, Zhao L. Combinatorial metabolic engineering of Escherichia coli for de novo production of structurally defined and homogeneous Amino oligosaccharides. Synth Syst Biotechnol 2024; 9:713-722. [PMID: 38868610 PMCID: PMC11167392 DOI: 10.1016/j.synbio.2024.05.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2024] [Revised: 05/02/2024] [Accepted: 05/20/2024] [Indexed: 06/14/2024] Open
Abstract
Amino oligosaccharides (AOs) possess various biological activities and are valuable in the pharmaceutical, food industries, and agriculture. However, the industrial manufacturing of AOs has not been realized yet, despite reports on physical, chemical, and biological approaches. In this study, the de novo production of chitin oligosaccharides (CHOS), a type of structurally defined AOs, was achieved in Escherichia coli through combinatorial pathway engineering. The most suitable glycosyltransferase for CHOS production was found to be NodCL from Mesorhizobium Loti. Then, by knocking out the nagB gene to block the flow of N-acetyl-d-glucosamine (NAG) to the glycolytic pathway in E. coli and adjusting the copy number of NodCL-coding gene, the CHOS yield was increased by 6.56 times. Subsequently, by introducing of UDP-N-acetylglucosamine (UDP-GlcNAc) salvage pathway for and optimizing fermentation conditions, the yield of CHOS reached 207.1 and 468.6 mg/L in shake-flask cultivation and a 5-L fed-batch bioreactor, respectively. Meanwhile, the concentration of UDP-GlcNAc was 91.0 mg/L, the highest level reported in E. coli so far. This study demonstrated, for the first time, the production of CHOS with distinct structures in plasmid-free E. coli, laying the groundwork for the biosynthesis of CHOS and providing a starting point for further engineering and commercial production.
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Affiliation(s)
- Jinqi Shi
- State Key Laboratory of Bioreactor Engineering, School of Biotechnology, East China University of Science and Technology, Shanghai, 200237, China
| | - Chen Deng
- State Key Laboratory of Bioreactor Engineering, School of Biotechnology, East China University of Science and Technology, Shanghai, 200237, China
- Shanghai Collaborative Innovation Center for Biomanufacturing Technology (SCICBT), Shanghai, 200237, China
| | - Chunyue Zhang
- State Key Laboratory of Bioreactor Engineering, School of Biotechnology, East China University of Science and Technology, Shanghai, 200237, China
| | - Shu Quan
- State Key Laboratory of Bioreactor Engineering, School of Biotechnology, East China University of Science and Technology, Shanghai, 200237, China
| | - Liqiang Fan
- State Key Laboratory of Bioreactor Engineering, School of Biotechnology, East China University of Science and Technology, Shanghai, 200237, China
- Shanghai Collaborative Innovation Center for Biomanufacturing Technology (SCICBT), Shanghai, 200237, China
| | - Liming Zhao
- State Key Laboratory of Bioreactor Engineering, School of Biotechnology, East China University of Science and Technology, Shanghai, 200237, China
- Organ Transplant Center, Shanghai Changzheng Hospital, Shanghai, 200003, China
- Shanghai Collaborative Innovation Center for Biomanufacturing Technology (SCICBT), Shanghai, 200237, China
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Controlled processivity in glycosyltransferases: A way to expand the enzymatic toolbox. Biotechnol Adv 2023; 63:108081. [PMID: 36529206 DOI: 10.1016/j.biotechadv.2022.108081] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Revised: 11/20/2022] [Accepted: 12/11/2022] [Indexed: 12/23/2022]
Abstract
Glycosyltransferases (GT) catalyse the biosynthesis of complex carbohydrates which are the most abundant group of molecules in nature. They are involved in several key mechanisms such as cell signalling, biofilm formation, host immune system invasion or cell structure and this in both prokaryotic and eukaryotic cells. As a result, research towards complete enzyme mechanisms is valuable to understand and elucidate specific structure-function relationships in this group of molecules. In a next step this knowledge could be used in GT protein engineering, not only for rational drug design but also for multiple biotechnological production processes, such as the biosynthesis of hyaluronan, cellooligosaccharides or chitooligosaccharides. Generation of these poly- and/or oligosaccharides is possible due to a common feature of several of these GTs: processivity. Enzymatic processivity has the ability to hold on to the growing polymer chain and some of these GTs can even control the number of glycosyl transfers. In a first part, recent advances in understanding the mechanism of various processive enzymes are discussed. To this end, an overview is given of possible engineering strategies for the purpose of new industrial and fundamental applications. In the second part of this review, we focused on specific chain length-controlling mechanisms, i.e., key residues or conserved regions, and this for both eukaryotic and prokaryotic enzymes.
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Weyer R, Hellmann MJ, Hamer-Timmermann SN, Singh R, Moerschbacher BM. Customized chitooligosaccharide production-controlling their length via engineering of rhizobial chitin synthases and the choice of expression system. Front Bioeng Biotechnol 2022; 10:1073447. [PMID: 36588959 PMCID: PMC9795070 DOI: 10.3389/fbioe.2022.1073447] [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: 10/18/2022] [Accepted: 11/28/2022] [Indexed: 12/15/2022] Open
Abstract
Chitooligosaccharides (COS) have attracted attention from industry and academia in various fields due to their diverse bioactivities. However, their conventional chemical production is environmentally unfriendly and in addition, defined and pure molecules are both scarce and expensive. A promising alternative is the in vivo synthesis of desired COS in microbial platforms with specific chitin synthases enabling a more sustainable production. Hence, we examined the whole cell factory approach with two well-established microorganisms-Escherichia coli and Corynebacterium glutamicum-to produce defined COS with the chitin synthase NodC from Rhizobium sp. GRH2. Moreover, based on an in silico model of the synthase, two amino acids potentially relevant for COS length were identified and mutated to direct the production. Experimental validation showed the influence of the expression system, the mutations, and their combination on COS length, steering the production from originally pentamers towards tetramers or hexamers, the latter virtually pure. Possible explanations are given by molecular dynamics simulations. These findings pave the way for a better understanding of chitin synthases, thus allowing a more targeted production of defined COS. This will, in turn, at first allow better research of COS' bioactivities, and subsequently enable sustainable large-scale production of oligomers.
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Ling M, Wu Y, Tian R, Liu Y, Yu W, Tao G, Lv X, Li J, Du G, Amaro RL, Liu L. Combinatorial pathway engineering of Bacillus subtilis for production of structurally defined and homogeneous chitooligosaccharides. Metab Eng 2022; 70:55-66. [PMID: 35033656 DOI: 10.1016/j.ymben.2022.01.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Revised: 12/30/2021] [Accepted: 01/12/2022] [Indexed: 11/16/2022]
Abstract
Chitooligosaccharides (COSs) have a widespread range of biological functions and an incredible potential for various pharmaceutical and agricultural applications. Although several physical, chemical, and biological techniques have been reported for COSs production, it is still a challenge to obtain structurally defined COSs with defined polymerization (DP) and acetylation patterns, which hampers the specific characterization and application of COSs. Herein, we achieved the de novo production of structurally defined COSs using combinatorial pathway engineering in Bacillus subtilis. Specifically, the COSs synthase NodC from Azorhizobium caulinodans was overexpressed in B. subtilis, leading to 30 ± 0.86 mg/L of chitin oligosaccharides (CTOSs), the homo-oligomers of N-acetylglucosamine (GlcNAc) with a well-defined DP lower than 6. Then introduction of a GlcNAc synthesis module to promote the supply of the sugar acceptor GlcNAc, reduced CTOSs production, which suggested that the activity of COSs synthase NodC and the supply of sugar donor UDP-GlcNAc may be the limiting steps for CTOSs synthesis. Therefore, 6 exogenous COSs synthase candidates were examined, and the nodCM from Mesorhizobium loti yielded the highest CTOSs titer of 560 ± 16 mg/L. Finally, both the de novo pathway and the salvage pathway of UDP-GlcNAc were engineered to further promote the biosynthesis of CTOSs. The titer of CTOSs in 3-L fed-batch bioreactor reached 4.82 ± 0.11 g/L (85.6% CTOS5, 7.5% CTOS4, 5.3% CTOS3 and 1.6% CTOS2), which was the highest ever reported. This is the first report proving the feasibility of the de novo production of structurally defined CTOSs by synthetic biology, and provides a good starting point for further engineering to achieve the commercial production.
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Affiliation(s)
- Meixi Ling
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China; Science Center for Future Foods, Jiangnan University, Wuxi, 214122, China
| | - Yaokang Wu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China; Science Center for Future Foods, Jiangnan University, Wuxi, 214122, China
| | - Rongzhen Tian
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China; Science Center for Future Foods, Jiangnan University, Wuxi, 214122, China
| | - Yanfeng Liu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China; Science Center for Future Foods, Jiangnan University, Wuxi, 214122, China
| | - Wenwen Yu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China; Science Center for Future Foods, Jiangnan University, Wuxi, 214122, China
| | - Guanjun Tao
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, 214122, China
| | - Xueqin Lv
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China; Science Center for Future Foods, Jiangnan University, Wuxi, 214122, China
| | - Jianghua Li
- Science Center for Future Foods, Jiangnan University, Wuxi, 214122, China
| | - Guocheng Du
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China; Science Center for Future Foods, Jiangnan University, Wuxi, 214122, China.
| | - Rodrigo Ledesma Amaro
- Department of Bioengineering and Centre for Synthetic Biology, Imperial College London, London, SW7 2AZ, UK
| | - Long Liu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China; Science Center for Future Foods, Jiangnan University, Wuxi, 214122, China.
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Kumar M, Rajput M, Soni T, Vivekanand V, Pareek N. Chemoenzymatic Production and Engineering of Chitooligosaccharides and N-acetyl Glucosamine for Refining Biological Activities. Front Chem 2020; 8:469. [PMID: 32671017 PMCID: PMC7329927 DOI: 10.3389/fchem.2020.00469] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2020] [Accepted: 05/05/2020] [Indexed: 01/07/2023] Open
Abstract
Chitooligosaccharides (COS) and N-acetyl glucosamine (GlcNAc) are currently of enormous relevance to pharmaceutical, nutraceutical, cosmetics, food, and agriculture industries due to their wide range of biological activities, which include antimicrobial, antitumor, antioxidant, anticoagulant, wound healing, immunoregulatory, and hypocholesterolemic effects. A range of methods have been developed for the synthesis of COS with a specific degree of polymerization along with high production titres. In this respect, chemical, enzymatic, and microbial means, along with modern genetic manipulation techniques, have been extensively explored; however no method has been able to competently produce defined COS and GlcNAc in a mono-system approach. Henceforth, the chitin research has turned toward increased exploration of chemoenzymatic processes for COS and GlcNAc generation. Recent developments in the area of green chemicals, mainly ionic liquids, proved vital for the specified COS and GlcNAc synthesis with better yield and purity. Moreover, engineering of COS and GlcNAc to generate novel derivatives viz. carboxylated, sulfated, phenolic acid conjugated, amino derived COS, etc., further improved their biological activities. Consequently, chemoenzymatic synthesis and engineering of COS and GlcNAc emerged as a useful approach to lead the biologically-active compound-based biomedical research to an advanced prospect in the forthcoming era.
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Affiliation(s)
- Manish Kumar
- Microbial Catalysis and Process Engineering Laboratory, Department of Microbiology, School of Life Sciences, Central University of Rajasthan, Ajmer, India
| | - Meenakshi Rajput
- Microbial Catalysis and Process Engineering Laboratory, Department of Microbiology, School of Life Sciences, Central University of Rajasthan, Ajmer, India
| | - Twinkle Soni
- Microbial Catalysis and Process Engineering Laboratory, Department of Microbiology, School of Life Sciences, Central University of Rajasthan, Ajmer, India
| | - Vivekanand Vivekanand
- Centre for Energy and Environment, Malaviya National Institute of Technology, Jaipur, India
| | - Nidhi Pareek
- Microbial Catalysis and Process Engineering Laboratory, Department of Microbiology, School of Life Sciences, Central University of Rajasthan, Ajmer, India
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Coussement P, Bauwens D, Peters G, Maertens J, De Mey M. Mapping and refactoring pathway control through metabolic and protein engineering: The hexosamine biosynthesis pathway. Biotechnol Adv 2020; 40:107512. [DOI: 10.1016/j.biotechadv.2020.107512] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Revised: 08/07/2019] [Accepted: 09/30/2019] [Indexed: 01/14/2023]
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Sun Z, Zou W, Huang J, Su Z, Bai Y. The triple-wavelength overlapping resonance Rayleigh scattering method and the fluorescence quenching method for the determination of chitooligosaccharides using trisodium-8-hydroxypyrene-1,3,6-trisulfonate as a probe. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2019; 220:117100. [PMID: 31141769 DOI: 10.1016/j.saa.2019.05.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Revised: 05/08/2019] [Accepted: 05/09/2019] [Indexed: 06/09/2023]
Abstract
In this assay, the triple-wavelength overlapping resonance Rayleigh scattering (TWO-RRS) method and the fluorescence quenching method for the quantitative detection of chitooligosaccharides (COS) were developed. In the weakly Britton-Robinson buffer solution, COS interacted with Trisodium-8-hydroxypyrene-1,3,6-trisulfonate (HPTS) to form an ion-association complex of HPTS-COS, which increased the RRS intensities at 321 nm, 430 nm and 511 nm and decreased the fluorescence intensities of the system at 512 nm. And the changes in the intensities of both methods were related to the changes in the concentration of COS. Moreover, for the TWO-RRS method, OP-10 made the RRS intensities increased stronger, finally, the three peaks' total was linear to the concentration of COS in the range of 1.00-8.00 μg/mL and the limit of detection (LOD) was 0.247 μg/mL, and for the fluorescence quenching method, the linear range was 0.50-3.50 μg/mL with the LOD of 0.108 μg/mL. Based on these, two new and fast spectral methods with high sensitivity and simplicity for the determination of trace COS had been established. The generation mechanism of the TWO-RRS and the fluorescence quenching was studied. At the same time, the two methods were applied to the determination of COS in health products with satisfactory results.
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Affiliation(s)
- Zijun Sun
- School of Public Health, Guangdong Pharmaceutical University, Guangzhou, Guangdong Province 510310, China
| | - Weiling Zou
- School of Public Health, Guangdong Pharmaceutical University, Guangzhou, Guangdong Province 510310, China
| | - Jieyi Huang
- School of Public Health, Guangdong Pharmaceutical University, Guangzhou, Guangdong Province 510310, China
| | - Zhengquan Su
- Guangdong Engineering Research Center of Natural Products and New Drugs, Guangdong Provincial University Engineering Technology Research Center of Natural Products and Drugs, Guangdong Pharmaceutical University, Guangzhou 510006, China; Guangdong Metabolic Diseases Research Center of Integrated Chinese and Western Medicine, Guangdong Pharmaceutical University, Guangzhou 510006, China.
| | - Yan Bai
- School of Public Health, Guangdong Pharmaceutical University, Guangzhou, Guangdong Province 510310, China.
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Metabolic engineering for the production of chitooligosaccharides: advances and perspectives. Emerg Top Life Sci 2018; 2:377-388. [DOI: 10.1042/etls20180009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2018] [Revised: 08/06/2018] [Accepted: 08/07/2018] [Indexed: 11/17/2022]
Abstract
Chitin oligosaccharides (CTOs) and its related compounds chitosan oligosaccharides (CSOs), collectively known as chitooligosaccharides (COs), exhibit numerous biological activities in applications in the nutraceutical, cosmetics, agriculture, and pharmaceutical industries. COs are currently produced by acid hydrolysis of chitin or chitosan, or enzymatic techniques with uncontrollable polymerization. Microbial fermentation by recombinant Escherichia coli, as an alternative method for the production of COs, shows new potential because it can produce a well-defined COs mixture and is an environmentally friendly process. In addition, Bacillus subtilis, a nonpathogenic, endotoxin-free, GRAS status bacterium, presents a new opportunity as a platform to produce COs. Here, we review the applications of COs and differences between CTOs and CSOs, summarize the current preparation approaches of COs, and discuss the future research potentials and challenges in the production of well-defined COs in B. subtilis by metabolic engineering.
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Identification of a Direct Biosynthetic Pathway for UDP- N-Acetylgalactosamine from Glucosamine-6-Phosphate in Thermophilic Crenarchaeon Sulfolobus tokodaii. J Bacteriol 2018; 200:JB.00048-18. [PMID: 29507091 DOI: 10.1128/jb.00048-18] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2018] [Accepted: 02/23/2018] [Indexed: 11/20/2022] Open
Abstract
Most organisms, from Bacteria to Eukarya, synthesize UDP-N-acetylglucosamine (UDP-GlcNAc) from fructose-6-phosphate via a four-step reaction, and UDP-N-acetylgalactosamine (UDP-GalNAc) can only be synthesized from UDP-GlcNAc by UDP-GlcNAc 4-epimerase. In Archaea, the bacterial-type UDP-GlcNAc biosynthetic pathway was reported for Methanococcales. However, the complete biosynthetic pathways for UDP-GlcNAc and UDP-GalNAc present in one archaeal species are unidentified. Previous experimental analyses on enzymatic activities of the ST0452 protein, identified from the thermophilic crenarchaeon Sulfolobus tokodaii, predicted the presence of both a bacterial-type UDP-GlcNAc and an independent UDP-GalNAc biosynthetic pathway in this archaeon. In the present work, functional analyses revealed that the recombinant ST2186 protein possessed an glutamine:fructose-6-phosphate amidotransferase activity and that the recombinant ST0242 protein possessed a phosphoglucosamine-mutase activity. Along with the acetyltransferase and uridyltransferase activities of the ST0452 protein, the activities of the ST2186 and ST0242 proteins confirmed the presence of a bacterial-type UDP-GlcNAc biosynthetic pathway in S. tokodaii In contrast, the UDP-GlcNAc 4-epimerase homologue gene was not detected within the genomic data. Thus, it was expected that galactosamine-1-phosphate or galactosamine-6-phosphate (GalN-6-P) was provided by conversion of glucosamine-1-phosphate or glucosamine-6-phosphate (GlcN-6-P). A novel epimerase converting GlcN-6-P to GalN-6-P was detected in a cell extract of S. tokodaii, and the N-terminal sequence of the purified protein indicated that the novel epimerase was encoded by the ST2245 gene. Along with the ST0242 phosphogalactosamine-mutase activity, this observation confirmed the presence of a novel UDP-GalNAc biosynthetic pathway from GlcN-6-P in S. tokodaii Discovery of the novel pathway provides a new insight into the evolution of nucleotide sugar metabolic pathways.IMPORTANCE In this work, a novel protein capable of directly converting glucosamine-6-phosphate to galactosamine-6-phosphate was successfully purified from a cell extract of the thermophilic crenarchaeon Sulfolobus tokodaii Confirmation of this novel activity using the recombinant protein indicates that S. tokodaii possesses a novel UDP-GalNAc biosynthetic pathway derived from glucosamine-6-phosphate. The distributions of this and related genes indicate the presence of three different types of UDP-GalNAc biosynthetic pathways: a direct pathway using a novel enzyme and two conversion pathways from UDP-GlcNAc using known enzymes. Additionally, Crenarchaeota species lacking all three pathways were found, predicting the presence of one more unknown pathway. Identification of these novel proteins and pathways provides important insights into the evolution of nucleotide sugar biosynthesis, as well as being potentially important industrially.
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Li K, Xing R, Liu S, Li P. Advances in preparation, analysis and biological activities of single chitooligosaccharides. Carbohydr Polym 2016; 139:178-90. [DOI: 10.1016/j.carbpol.2015.12.016] [Citation(s) in RCA: 94] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2015] [Accepted: 12/07/2015] [Indexed: 02/07/2023]
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Naqvi S, Moerschbacher BM. The cell factory approach toward biotechnological production of high-value chitosan oligomers and their derivatives: an update. Crit Rev Biotechnol 2015; 37:11-25. [DOI: 10.3109/07388551.2015.1104289] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Wang S, Fu X, Liu Y, Liu XW, Wang L, Fang J, Wang PG. Probing the roles of conserved residues in uridyltransferase domain of Escherichia coli K12 GlmU by site-directed mutagenesis. Carbohydr Res 2015; 413:70-4. [PMID: 26101844 DOI: 10.1016/j.carres.2015.05.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2015] [Revised: 05/18/2015] [Accepted: 05/21/2015] [Indexed: 11/30/2022]
Abstract
N-Acetylglucosamine-1-phosphate uridyltransferase (GlmU) is a bifunctional enzyme that catalyzes both acetyltransfer and uridyltransfer reactions in the prokaryotic UDP-GlcNAc biosynthesis pathway. Our previous study demonstrated that the uridyltransferase domain of GlmU (tGlmU) exhibited a flexible substrate specificity, which could be further applied in unnatural sugar nucleotides preparation. However, the structural basis of tolerating variant substrates is still not clear. Herein, we further investigated the roles of several highly conserved amino acid residues involved in substrate binding and recognition by structure- and sequence-guided site-directed mutagenesis. Out of total 16 mutants designed, tGlmU Q76E mutant which had a novel catalytic activity to convert CTP and GlcNAc-1P into unnatural sugar nucleotide CDP-GlcNAc was identified. Furthermore, tGlmU Y103F and N169R mutants were also investigated to have enhanced uridyltransferase activities compared with wide-type tGlmU.
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Affiliation(s)
- Shuaishuai Wang
- National Glycoengineering Research Center, Shandong University, Jinan, Shandong 250100, People's Republic of China; The State Key Laboratory of Microbial Technology and School of Life Sciences, Shandong University, Jinan, Shandong 250100, People's Republic of China
| | - Xuan Fu
- National Glycoengineering Research Center, Shandong University, Jinan, Shandong 250100, People's Republic of China
| | - Yunpeng Liu
- The State Key Laboratory of Microbial Technology and School of Life Sciences, Shandong University, Jinan, Shandong 250100, People's Republic of China; Department of Chemistry, Georgia State University, P.O. Box 4098, Atlanta, GA 30302-4098, USA
| | - Xian-wei Liu
- National Glycoengineering Research Center, Shandong University, Jinan, Shandong 250100, People's Republic of China
| | - Lin Wang
- Department of Food Science and Engineering, Nanshan University, Yantai, Shandong 265713, People's Republic of China
| | - Junqiang Fang
- National Glycoengineering Research Center, Shandong University, Jinan, Shandong 250100, People's Republic of China.
| | - Peng George Wang
- National Glycoengineering Research Center, Shandong University, Jinan, Shandong 250100, People's Republic of China; Department of Chemistry, Georgia State University, P.O. Box 4098, Atlanta, GA 30302-4098, USA
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