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Wei X, Yang L, Chen Z, Xia W, Chen Y, Cao M, He N. Molecular weight control of poly-γ-glutamic acid reveals novel insights into extracellular polymeric substance synthesis in Bacillus licheniformis. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2024; 17:60. [PMID: 38711141 DOI: 10.1186/s13068-024-02501-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2024] [Accepted: 04/04/2024] [Indexed: 05/08/2024]
Abstract
BACKGROUND The structural diversity of extracellular polymeric substances produced by microorganisms is attracting particular attention. Poly-gamma-glutamic acid (γ-PGA) is a widely studied extracellular polymeric substance from Bacillus species. The function of γ-PGA varies with its molecular weight (Mw). RESULTS Herein, different endogenous promoters in Bacillus licheniformis were selected to regulate the expression levels of pgdS, resulting in the formation of γ-PGA with Mw values ranging from 1.61 × 103 to 2.03 × 104 kDa. The yields of γ-PGA and exopolysaccharides (EPS) both increased in the pgdS engineered strain with the lowest Mw and viscosity, in which the EPS content was almost tenfold higher than that of the wild-type strain. Subsequently, the compositions of EPS from the pgdS engineered strain also changed. Metabolomics and RT-qPCR further revealed that improving the transportation efficiency of EPS and the regulation of carbon flow of monosaccharide synthesis could affect the EPS yield. CONCLUSIONS Here, we present a novel insight that increased pgdS expression led to the degradation of γ-PGA Mw and changes in EPS composition, thereby stimulating EPS and γ-PGA production. The results indicated a close relationship between γ-PGA and EPS in B. licheniformis and provided an effective strategy for the controlled synthesis of extracellular polymeric substances.
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Affiliation(s)
- Xiaoyu Wei
- Department of Chemical and Biochemical Engineering, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, Fujian, China
- The Key Lab for Synthetic Biotechnology of Xiamen City, Xiamen University, Xiamen, People's Republic of China
| | - Lijie Yang
- Department of Chemical and Biochemical Engineering, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, Fujian, China
- The Key Lab for Synthetic Biotechnology of Xiamen City, Xiamen University, Xiamen, People's Republic of China
| | - Zhen Chen
- College of Life Science, Xinyang Normal University, Xinyang, 464000, China.
| | - Wenhao Xia
- Department of Chemical and Biochemical Engineering, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, Fujian, China
- The Key Lab for Synthetic Biotechnology of Xiamen City, Xiamen University, Xiamen, People's Republic of China
| | - Yongbin Chen
- Department of Chemical and Biochemical Engineering, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, Fujian, China
- The Key Lab for Synthetic Biotechnology of Xiamen City, Xiamen University, Xiamen, People's Republic of China
| | - Mingfeng Cao
- Department of Chemical and Biochemical Engineering, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, Fujian, China.
- The Key Lab for Synthetic Biotechnology of Xiamen City, Xiamen University, Xiamen, People's Republic of China.
| | - Ning He
- Department of Chemical and Biochemical Engineering, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, Fujian, China.
- The Key Lab for Synthetic Biotechnology of Xiamen City, Xiamen University, Xiamen, People's Republic of China.
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2
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Zhao M, Zhu Y, Wang H, Zhang W, Mu W. Recent advances on N-acetylneuraminic acid: Physiological roles, applications, and biosynthesis. Synth Syst Biotechnol 2023; 8:509-519. [PMID: 37502821 PMCID: PMC10369400 DOI: 10.1016/j.synbio.2023.06.009] [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: 05/21/2023] [Revised: 06/22/2023] [Accepted: 06/27/2023] [Indexed: 07/29/2023] Open
Abstract
N-Acetylneuraminic acid (Neu5Ac), the most common type of Sia, generally acts as the terminal sugar in cell surface glycans, glycoconjugates, oligosaccharides, lipo-oligosaccharides, and polysaccharides, thus exerting numerous physiological functions. The extensive applications of Neu5Ac in the food, cosmetic, and pharmaceutical industries make large-scale production of this chemical desirable. Biosynthesis which is associated with important application potential and environmental friendliness has become an indispensable approach for large-scale synthesis of Neu5Ac. In this review, the physiological roles of Neu5Ac was first summarized in detail. Second, the safety evaluation, regulatory status, and applications of Neu5Ac were discussed. Third, enzyme-catalyzed preparation, whole-cell biocatalysis, and microbial de novo synthesis of Neu5Ac were comprehensively reviewed. In addition, we discussed the main challenges of Neu5Ac de novo biosynthesis, such as screening and engineering of key enzymes, identifying exporters of intermediates and Neu5Ac, and balancing cell growth and biosynthesis. The corresponding strategies and systematic strategies were proposed to overcome these challenges and facilitate Neu5Ac industrial-scale production.
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Affiliation(s)
- Mingli Zhao
- State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi, Jiangsu, 214122, PR China
| | - Yingying Zhu
- State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi, Jiangsu, 214122, PR China
| | - Hao Wang
- Bloomage Biotechnology Corp., Ltd., Jinan, Shandong, 250010, PR China
| | - Wenli Zhang
- State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi, Jiangsu, 214122, PR China
| | - Wanmeng Mu
- State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi, Jiangsu, 214122, PR China
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3
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Sui D, Liang K, Gui Y, Du Z, Xin D, Yu G, Zhai W, Liu X, Song Y, Deng Y. Optimization design of sialic acid derivatives enhances the performance of liposomes for modulating immunosuppressive tumor microenvironments. Life Sci 2022; 310:121081. [DOI: 10.1016/j.lfs.2022.121081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2022] [Revised: 10/06/2022] [Accepted: 10/11/2022] [Indexed: 11/05/2022]
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4
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Rossing E, Pijnenborg JFA, Boltje TJ. Chemical tools to track and perturb the expression of sialic acid and fucose monosaccharides. Chem Commun (Camb) 2022; 58:12139-12150. [PMID: 36222364 PMCID: PMC9623448 DOI: 10.1039/d2cc04275d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2022] [Accepted: 10/05/2022] [Indexed: 11/24/2022]
Abstract
The biosynthesis of glycans is a highly conserved biological process and found in all domains of life. The expression of cell surface glycans is increasingly recognized as a target for therapeutic intervention given the role of glycans in major pathologies such as cancer and microbial infection. Herein, we summarize our contributions to the development of unnatural monosaccharide derivatives to infiltrate and alter the expression of both mammalian and bacterial glycans and their therapeutic application.
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Affiliation(s)
- Emiel Rossing
- Department of Synthetic Organic Chemistry, Institute for Molecules and Materials, Radboud University, Heyendaalseweg 135, 6525AJ, Nijmegen, The Netherlands.
| | - Johan F A Pijnenborg
- Department of Synthetic Organic Chemistry, Institute for Molecules and Materials, Radboud University, Heyendaalseweg 135, 6525AJ, Nijmegen, The Netherlands.
| | - Thomas J Boltje
- Department of Synthetic Organic Chemistry, Institute for Molecules and Materials, Radboud University, Heyendaalseweg 135, 6525AJ, Nijmegen, The Netherlands.
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5
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Glycosyl Formates: Glycosylations with Neighboring-Group Participation. Molecules 2022; 27:molecules27196244. [PMID: 36234778 PMCID: PMC9572138 DOI: 10.3390/molecules27196244] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Revised: 09/15/2022] [Accepted: 09/19/2022] [Indexed: 11/22/2022] Open
Abstract
Protected 2-O-benzyolated glycosyl formates were synthesized in one-step from the corresponding orthoester using formic acid as the sole reagent. Glucopyranosyl, mannopyranosyl and galactopyranosyl donors were synthesized and their glycosylation properties studied using model glycosyl acceptors of varied steric bulk and reactivity. Bismuth triflate was the preferred catalyst and KPF6 was used as an additive. The 1,2-trans-selectivities resulting from neighboring-group participation were excellent and the glycosylations were generally high-yielding.
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6
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Hu ZX, Cheng C, Li YQ, Qi XH, Wang T, Liu L, Voglmeir J. Recombinant snail sialic acid aldolase is promiscuous towards aliphatic aldehydes. Chembiochem 2022; 23:e202200074. [PMID: 35543120 DOI: 10.1002/cbic.202200074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Revised: 05/10/2022] [Indexed: 11/08/2022]
Abstract
Aldolases are enzymes that reversibly catalyze the cleavage of carbon-carbon bonds. Here we describe a recombinant sialic acid aldolase originating from the freshwater snail Biomphalaria glabrata (sNPL), and compare its substrate spectrum with a sialic acid aldolase originating from chicken (chNPL). In contrast to vertebrate animals which can synthesize, degrade, and incorporate sialic acids on glycoconjugate ubiquitously, snails (as all mollusks) cannot synthesize sialic acids endogenously, and therefore the biological function and substrate scope of sNPL ought to differ significantly from vertebrate sialic aldolases such as chNPL. sNPL was active towards a series of sialic acid derivatives but was in contrast to chNPL unable to catalyze the cleavage of N-acetylneuraminic acid into N-acetylmannosamine and pyruvate. Interestingly, chNPL and sNPL showed contrasting C4 (R) / (S) diastereoselectivity towards the substrates d-mannose and d-galactose in the presence of pyruvate. In addition, sNPL was also able to synthesize a series of 4-hydroxy-2-oxoates using the corresponding aliphatic aldehyde substrates in the presence of pyruvate, which could be not achieved by chNPL.
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Affiliation(s)
- Zi-Xuan Hu
- Nanjing Agricultural University - Weigang Campus: Nanjing Agricultural University, College of Food Science and Technology, CHINA
| | - Cheng Cheng
- Nanjing Agricultural University - Weigang Campus: Nanjing Agricultural University, College of Food Science and Technology, CHINA
| | - Yu-Qian Li
- Nanjing Agricultural University - Weigang Campus: Nanjing Agricultural University, College of Food Science and Technology, CHINA
| | - Xiao-Han Qi
- Nanjing Agricultural University - Weigang Campus: Nanjing Agricultural University, College of Food Science and Technology, CHINA
| | - Ting Wang
- Nanjing Agricultural University - Weigang Campus: Nanjing Agricultural University, College of Food Science and Technology, CHINA
| | - Li Liu
- Nanjing Agricultural University - Weigang Campus: Nanjing Agricultural University, College of Food Science and Technology, CHINA
| | - Josef Voglmeir
- Nanjing Agricultural University, College of Food Science And Technology, 1 Weigang, 210095, Nanjing, CHINA
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7
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Abstract
Biocatalysis has an enormous impact on chemical synthesis. The waves in which biocatalysis has developed, and in doing so changed our perception of what organic chemistry is, were reviewed 20 and 10 years ago. Here we review the consequences of these waves of development. Nowadays, hydrolases are widely used on an industrial scale for the benign synthesis of commodity and bulk chemicals and are fully developed. In addition, further enzyme classes are gaining ever increasing interest. Particularly, enzymes catalysing selective C-C-bond formation reactions and enzymes catalysing selective oxidation and reduction reactions are solving long-standing synthetic challenges in organic chemistry. Combined efforts from molecular biology, systems biology, organic chemistry and chemical engineering will establish a whole new toolbox for chemistry. Recent developments are critically reviewed.
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Affiliation(s)
- Ulf Hanefeld
- Biocatalysis, Department of Biotechnology, Delft University of Technology, Van der Maasweg 9, The Netherlands.
| | - Frank Hollmann
- Biocatalysis, Department of Biotechnology, Delft University of Technology, Van der Maasweg 9, The Netherlands.
| | - Caroline E Paul
- Biocatalysis, Department of Biotechnology, Delft University of Technology, Van der Maasweg 9, The Netherlands.
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8
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Moons SJ, Rossing E, Heming JJA, Janssen MAC, van Scherpenzeel M, Lefeber DJ, de Jonge MI, Langereis JD, Boltje TJ. Structure-Activity Relationship of Fluorinated Sialic Acid Inhibitors for Bacterial Sialylation. Bioconjug Chem 2021; 32:1047-1051. [PMID: 34043338 PMCID: PMC8382218 DOI: 10.1021/acs.bioconjchem.1c00194] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 05/23/2021] [Indexed: 11/29/2022]
Abstract
Bacterial pathogens such as Nontypeable Haemophilus influenzae (NTHi) can evade the immune system by taking up and presenting host-derived sialic acids. Herein, we report a detailed structure-activity relationship of sialic acid-based inhibitors that prevent the transfer of host sialic acids to NTHi. We report the synthesis and biological evaluation of C-5, C-8, and C-9 derivatives of the parent compound 3-fluorosialic acid (SiaNFAc). Small modifications are tolerated at the C-5 and C-9 positions, while the C-8 position does not allow for modification. These structure-activity relationships define the chemical space available to develop selective bacterial sialylation inhibitors.
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Affiliation(s)
- Sam J. Moons
- Cluster
of Molecular Chemistry, Institute for Molecules and Materials, Radboud University Nijmegen, Nijmegen 6525 AJ, The Netherlands
| | - Emiel Rossing
- Cluster
of Molecular Chemistry, Institute for Molecules and Materials, Radboud University Nijmegen, Nijmegen 6525 AJ, The Netherlands
| | - Jurriaan J. A. Heming
- Cluster
of Molecular Chemistry, Institute for Molecules and Materials, Radboud University Nijmegen, Nijmegen 6525 AJ, The Netherlands
| | - Mathilde A. C.
H. Janssen
- Cluster
of Molecular Chemistry, Institute for Molecules and Materials, Radboud University Nijmegen, Nijmegen 6525 AJ, The Netherlands
| | - Monique van Scherpenzeel
- Translational
Metabolic Laboratory, Department of Neurology, Donders Center for
Brain Cognition and Behavior, Radboud University
Medical Center, Nijmegen 6525 GA, The Netherlands
| | - Dirk J. Lefeber
- Translational
Metabolic Laboratory, Department of Neurology, Donders Center for
Brain Cognition and Behavior, Radboud University
Medical Center, Nijmegen 6525 GA, The Netherlands
| | - Marien I. de Jonge
- Laboratory
of Medical Immunology, Radboud Center for Infectious Diseases, Radboud
Institute for Molecular Sciences, Radboud
University Medical Center, Nijmegen 6525 GA, The Netherlands
| | - Jeroen D. Langereis
- Laboratory
of Medical Immunology, Radboud Center for Infectious Diseases, Radboud
Institute for Molecular Sciences, Radboud
University Medical Center, Nijmegen 6525 GA, The Netherlands
| | - Thomas J. Boltje
- Cluster
of Molecular Chemistry, Institute for Molecules and Materials, Radboud University Nijmegen, Nijmegen 6525 AJ, The Netherlands
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9
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de Martino MT, Tonin F, Bloemendal VRLJ, Hanefeld U, Rutjes FPJT, van Hest JCM. Compartmentalized cross-linked enzyme nano aggregates ( c-CLE nAs) toward pharmaceutical transformations. RSC Adv 2021; 11:21857-21861. [PMID: 35478789 PMCID: PMC9034143 DOI: 10.1039/d1ra04332c] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Accepted: 06/14/2021] [Indexed: 12/13/2022] Open
Abstract
A new immobilization strategy using compartmentalized nanoreactors is herein reported for two biocatalytic processes: (1) N-acetylneuraminate lyase (NAL) is internalized in NAL-c-CLEnAs and used in a continuous flow aldol condensation of N-acetyl-d-mannosamine with sodium pyruvate to N-acetylneuraminic acid; (2) two hydroxysteroid dehydrogenases (HSDH) 7α- and 7β-HSDH are incorporated in c-CLEnAs and used in a two-step cascade batch synthesis of ursodeoxycholic acid (UDCA). The versatile use of c-CLEnA demonstrates that this immobilization methodology is a valuable addition to the toolbox of synthetic chemists.
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Affiliation(s)
- M Teresa de Martino
- Department of Chemical Engineering & Chemistry, Institute for Complex Molecular Systems, Eindhoven University of Technology PO Box 513 5600 MB Eindhoven The Netherlands
| | - Fabio Tonin
- Department of Biotechnology, Delft University of Technology Van der Maasweg 9 2629 HZ Delft The Netherlands
| | - Victor R L J Bloemendal
- Department of Chemical Engineering & Chemistry, Institute for Complex Molecular Systems, Eindhoven University of Technology PO Box 513 5600 MB Eindhoven The Netherlands .,Institute for Molecules and Materials, Radboud University Heyendaalseweg 135 6525 AJ Nijmegen The Netherlands
| | - Ulf Hanefeld
- Department of Biotechnology, Delft University of Technology Van der Maasweg 9 2629 HZ Delft The Netherlands
| | - Floris P J T Rutjes
- Institute for Molecules and Materials, Radboud University Heyendaalseweg 135 6525 AJ Nijmegen The Netherlands
| | - Jan C M van Hest
- Department of Chemical Engineering & Chemistry, Institute for Complex Molecular Systems, Eindhoven University of Technology PO Box 513 5600 MB Eindhoven The Netherlands
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10
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Metabolic Glycoengineering in hMSC-TERT as a Model for Skeletal Precursors by Using Modified Azide/Alkyne Monosaccharides. Int J Mol Sci 2021; 22:ijms22062820. [PMID: 33802220 PMCID: PMC7999278 DOI: 10.3390/ijms22062820] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 03/03/2021] [Accepted: 03/08/2021] [Indexed: 12/28/2022] Open
Abstract
Metabolic glycoengineering enables a directed modification of cell surfaces by introducing target molecules to surface proteins displaying new features. Biochemical pathways involving glycans differ in dependence on the cell type; therefore, this technique should be tailored for the best results. We characterized metabolic glycoengineering in telomerase-immortalized human mesenchymal stromal cells (hMSC-TERT) as a model for primary hMSC, to investigate its applicability in TERT-modified cell lines. The metabolic incorporation of N-azidoacetylmannosamine (Ac4ManNAz) and N-alkyneacetylmannosamine (Ac4ManNAl) into the glycocalyx as a first step in the glycoengineering process revealed no adverse effects on cell viability or gene expression, and the in vitro multipotency (osteogenic and adipogenic differentiation potential) was maintained under these adapted culture conditions. In the second step, glycoengineered cells were modified with fluorescent dyes using Cu-mediated click chemistry. In these analyses, the two mannose derivatives showed superior incorporation efficiencies compared to glucose and galactose isomers. In time-dependent experiments, the incorporation of Ac4ManNAz was detectable for up to six days while Ac4ManNAl-derived metabolites were absent after two days. Taken together, these findings demonstrate the successful metabolic glycoengineering of immortalized hMSC resulting in transient cell surface modifications, and thus present a useful model to address different scientific questions regarding glycosylation processes in skeletal precursors.
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11
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Yang H, Lu L, Chen X. An overview and future prospects of sialic acids. Biotechnol Adv 2020; 46:107678. [PMID: 33285252 DOI: 10.1016/j.biotechadv.2020.107678] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2020] [Revised: 11/11/2020] [Accepted: 11/30/2020] [Indexed: 12/21/2022]
Abstract
Sialic acids (Sias) are negatively charged functional monosaccharides present in a wide variety of natural sources (plants, animals and microorganisms). Sias play an important role in many life processes, which are widely applied in the medical and food industries as intestinal antibacterials, antivirals, anti-oxidative agents, food ingredients, and detoxification agents. Most Sias are composed of N-acetylneuraminic acid (Neu5Ac, >99%), and Sia is its most commonly used name. In this article, we review Sias in terms of their structures, applications, determination methods, metabolism, and production strategies. In particular, we summarise and compare different production strategies, including extraction from natural sources, chemical synthesis, polymer decomposition, enzymatic synthesis, whole-cell catalysis, and de novo biosynthesis via microorganism fermentation. We also discuss research on their physiological functions and applications, barriers to efficient production, and strategies for overcoming these challenges. We focus on efficient de novo biosynthesis strategies for Neu5Ac via microbial fermentation using novel synthetic biology tools and methods that may be applied in future. This work provides a comprehensive overview of recent advances on Sias, and addresses future challenges regarding their functions, applications, and production.
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Affiliation(s)
- Haiquan Yang
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
| | - Liping Lu
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China; College of life Science and Engineering, Northwest Minzu University, Lanzhou 730030, China
| | - Xianzhong Chen
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China.
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12
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Characterization of Sialic Acid-Binding Immunoglobulin-Type Lectins in Fish Reveals Teleost-Specific Structures and Expression Patterns. Cells 2020; 9:cells9040836. [PMID: 32244286 PMCID: PMC7226832 DOI: 10.3390/cells9040836] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 03/23/2020] [Accepted: 03/24/2020] [Indexed: 12/15/2022] Open
Abstract
The cellular glycocalyx of vertebrates is frequently decorated with sialic acid residues. These sialylated structures are recognized by sialic acid-binding immunoglobulin-type lectins (Siglecs) of immune cells, which modulate their responsiveness. Fifteen Siglecs are known to be expressed in humans, but only four Siglecs are regularly present in fish: Siglec1, CD22, myelin-associated glycoprotein (MAG), and Siglec15. While several studies have dealt with the physiological roles of these four Siglecs in mammals, little is known about Siglecs in fish. In the present manuscript, the expression landscapes of these Siglecs were determined in the two salmonid species Oncorhynchus mykiss and Coregonus maraena and in the percid fish Sander lucioperca. This gene-expression profiling revealed that the expression of MAG is not restricted to neuronal cells but is detectable in all analyzed blood cells, including erythrocytes. The teleostean MAG contains the inhibitory motif ITIM; therefore, an additional immunomodulatory function of MAG is likely to be present in fish. Besides MAG, Siglec1, CD22, and Siglec15 were also expressed in all analyzed blood cell populations. Interestingly, the expression profiles of genes encoding Siglecs and particular associated enzymes changed in a gene- and tissue-specific manner when Coregonus maraena was exposed to handling stress. Thus, the obtained data indicate once more that stress directly affects immune-associated processes.
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Orsy G, Fülöp F, Mándity IM. Direct amide formation in a continuous-flow system mediated by carbon disulfide. Catal Sci Technol 2020. [DOI: 10.1039/d0cy01603a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
We report a direct flow-based synthesis of amides. The developed approach is prominently simple and various aliphatic and aromatic amides were synthetized with excellent yields. The technology is considerably robust and easy scale-up was carried out.
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Affiliation(s)
- György Orsy
- Institute of Pharmaceutical Chemistry
- University of Szeged
- H-6720 Szeged
- Hungary
- MTA TTK Lendület Artificial Transporter Research Group
| | - Ferenc Fülöp
- Institute of Pharmaceutical Chemistry
- University of Szeged
- H-6720 Szeged
- Hungary
- Research Group of Stereochemistry of the Hungarian Academy of Sciences
| | - István M. Mándity
- MTA TTK Lendület Artificial Transporter Research Group
- Institute of Materials and Environmental Chemistry
- Research Center for Natural Sciences
- Hungarian Academy of Sciences
- 1117 Budapest
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