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Kim J, Kim EJ, Ko HJ, Lee YH, Hong SK, Shin M, Lee JH, Kwak W. Construction of Streptomyces coelicolor A3(2) mutants that exclusively produce NA4/NA6 intermediates of agarose metabolism through mutation induction. Sci Rep 2023; 13:18968. [PMID: 37923760 PMCID: PMC10624881 DOI: 10.1038/s41598-023-46410-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Accepted: 10/31/2023] [Indexed: 11/06/2023] Open
Abstract
NA4/NA6, an intermediate degradation product of β-agarase, is a high value-added product with anticancer, anti-obesity, and anti-diabetic effects. Therefore, a method that enables the efficient production of NA4/NA6 would be useful from economic and medical perspectives. In this study, we aimed to generate a Streptomyces coelicolor A3(2) mutant M22-2C43 that produces NA4/NA6 as a final product; this method serves as a more efficient alternative to the enzymatic conversion of β-agarase for the generation of these products. The M22-2C43 strain was generated through two rounds of mutagenesis and screening for increased β-agarase activity and effective production of NA4/NA6. We assembled the complete genomes of two mutants, M22 and M22-2C43, which were identified following a two-round screening. Large and small genetic changes were found in these two mutants, including the loss of two plasmids present in wild-type S. coelicolor A3(2) and chromosome circularization of mutant M22-2C43. These findings suggest that mutant M22-2C43 can produce NA4/NA6 as a degradation product due to functional inactivation of the dagB gene through a point mutation (G474A), ultimately preventing further degradation of NA4/NA6 to NA2. To our knowledge, this is the first report of a microbial strain that can effectively produce NA4/NA6 as the main degradation product of β-agarase, opening the door for the use of this species for the large-scale production of this valuable product.
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Affiliation(s)
- Jina Kim
- Department of Medical and Biological Sciences, The Catholic University of Korea, Bucheon, 14662, Republic of Korea
| | - Eun Joo Kim
- Dyne Bio Inc., Seongnam-si, Gyeonggido, 13209, Republic of Korea
| | - Hye-Jeong Ko
- Dyne Bio Inc., Seongnam-si, Gyeonggido, 13209, Republic of Korea
| | - Yeon-Hee Lee
- Dyne Bio Inc., Seongnam-si, Gyeonggido, 13209, Republic of Korea
| | - Soon-Kwang Hong
- Department of Biological Science and Bioinformatics, Myongji University, 116 Myongji-Ro, Cheoin-gu, Yongin, 17058, Gyeonggido, Korea
| | - Miyoung Shin
- Department of Pathology, Yale University School of Medicine, New Haven, CT, 06510, USA
| | - Je Hyeon Lee
- Dyne Bio Inc., Seongnam-si, Gyeonggido, 13209, Republic of Korea.
| | - Woori Kwak
- Department of Medical and Biological Sciences, The Catholic University of Korea, Bucheon, 14662, Republic of Korea.
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Tsevelkhoroloo M, Dhakshnamoorthy V, Hong YS, Lee CR, Hong SK. Bifunctional and monofunctional α-neoagarooligosaccharide hydrolases from Streptomyces coelicolor A3(2). Appl Microbiol Biotechnol 2023:10.1007/s00253-023-12552-x. [PMID: 37184654 DOI: 10.1007/s00253-023-12552-x] [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: 01/26/2023] [Revised: 04/11/2023] [Accepted: 04/15/2023] [Indexed: 05/16/2023]
Abstract
Agar is a galactan and a major component of the red algal cell wall. Agar is metabolized only by specific microorganisms. The final step of the β-agarolytic pathway is mediated by α-neoagarooligosaccharide hydrolase (α-NAOSH), which cleaves neoagarobiose to D-galactose and 3,6-anhydro-α-L-galactose. In the present study, two α-NAOSHs, SCO3481 and SCO3479, were identified in Streptomyces coelicolor A3(2). SCO3481 (370 amino acids, 41.12 kDa) and SCO3479 (995 amino acids, 108.8 kDa) catalyzed the hydrolysis of the α-(1,3) glycosidic bonds of neoagarobiose, neoagarotetraose, and neoagarohexaose at the nonreducing ends, releasing 3,6-anhydro-α-L-galactose. Both were intracellular proteins without any signal peptides for secretion. Similar to all α-NAOSHs reported to date, SCO3481 belonged to the glycosyl hydrolase (GH) 117 family and formed dimers. On the other hand, SCO3479 was a large monomeric α-NAOSH belonging to the GH2 family with a β-galactosidase domain. SCO3479 also clearly showed β-galactosidase activity toward lactose and artificial substrates, but SCO3481 did not. The optimum conditions for α-NAOSH were pH 6.0 and 25 °C for SCO3481, and pH 6.0 and 30 °C for SCO3479. Enzymatic activity was enhanced by Co2+ for SCO3481 and Mg2+ for SCO3479. The β-galactosidase activity of SCO3479 was maximum at pH 7.0 and 50 °C and was increased by Mg2+. Many differences were evident in the kinetic parameters of each enzyme. Although SCO3481 is typical of the GH117 family, SCO3479 is a novel α-NAOSH that was first reported in the GH2 family. SCO3479, a unique bifunctional enzyme with α-NAOSH and β-galactosidase activities, has many advantages for industrial applications. KEY POINTS: • SCO3481 is a dimeric α-neoagarooligosaccharide hydrolase belonging to GH117. • SCO3479 is a monomeric α-neoagarooligosaccharide hydrolase belonging to GH2. • SCO3479 is a novel and unique bifunctional enzyme that also acts as a β-galactosidase.
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Affiliation(s)
- Maral Tsevelkhoroloo
- Department of Bioscience and Bioinformatics, Myongji University, 116 Myongji-Ro, Yongin, Gyeonggido, 17058, Republic of Korea
| | - Vijayalakshmi Dhakshnamoorthy
- Department of Bioscience and Bioinformatics, Myongji University, 116 Myongji-Ro, Yongin, Gyeonggido, 17058, Republic of Korea
| | - Young-Soo Hong
- Anticancer Agent Research Center, Korea Research Institute of Bioscience and Biotechnology, 30 Yeongudanji-Ro, Cheongju, Chungbuk, 28116, Republic of Korea
| | - Chang-Ro Lee
- Department of Bioscience and Bioinformatics, Myongji University, 116 Myongji-Ro, Yongin, Gyeonggido, 17058, Republic of Korea
| | - Soon-Kwang Hong
- Department of Bioscience and Bioinformatics, Myongji University, 116 Myongji-Ro, Yongin, Gyeonggido, 17058, Republic of Korea.
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3
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Schulz S, Schall C, Stehle T, Breitmeyer C, Krysenko S, Mitulski A, Wohlleben W. Optimization of the precursor supply for an enhanced FK506 production in Streptomyces tsukubaensis. Front Bioeng Biotechnol 2022; 10:1067467. [DOI: 10.3389/fbioe.2022.1067467] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Accepted: 11/04/2022] [Indexed: 11/19/2022] Open
Abstract
Tacrolimus (FK506) is a macrolide widely used as immunosuppressant to prevent transplant rejection. Synthetic production of FK506 is not efficient and costly, whereas the biosynthesis of FK506 is complex and the level produced by the wild type strain, Streptomyces tsukubaensis, is very low. We therefore engineered FK506 biosynthesis and the supply of the precursor L-lysine to generate strains with improved FK506 yield. To increase FK506 production, first the intracellular supply of the essential precursor lysine was improved in the native host S. tsukubaensis NRRL 18488 by engineering the lysine biosynthetic pathway. Therefore, a feedback deregulated aspartate kinase AskSt* of S. tsukubaensis was generated by site directed mutagenesis. Whereas overexpression of AskSt* resulted only in a 17% increase in FK506 yield, heterologous overexpression of a feedback deregulated AskCg* from Corynebacterium glutamicum was proven to be more efficient. Combined overexpression of AskCg* and DapASt, showed a strong enhancement of the intracellular lysine pool following increase in the yield by approximately 73% compared to the wild type. Lysine is coverted into the FK506 building block pipecolate by the lysine cyclodeaminase FkbL. Construction of a ∆fkbL mutant led to a complete abolishment of the FK506 production, confirming the indispensability of this enzyme for FK506 production. Chemical complementation of the ∆fkbL mutant by feeding pipecolic acid and genetic complementation with fkbL as well as with other lysine cyclodeaminase genes (pipAf, pipASt, originating from Actinoplanes friuliensis and Streptomyces pristinaespiralis, respectively) completely restored FK506 production. Subsequently, FK506 production was enchanced by heterologous overexpression of PipAf and PipASp in S. tsukubaensis. This resulted in a yield increase by 65% compared to the WT in the presence of PipAf from A. friuliensis. For further rational yield improvement, the crystal structure of PipAf from A. friuliensis was determined at 1.3 Å resolution with the cofactor NADH bound and at 1.4 Å with its substrate lysine. Based on the structure the Ile91 residue was replaced by Val91 in PipAf, which resulted in an overall increase of FK506 production by approx. 100% compared to the WT.
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Hwang S, Lee Y, Kim JH, Kim G, Kim H, Kim W, Cho S, Palsson BO, Cho BK. Streptomyces as Microbial Chassis for Heterologous Protein Expression. Front Bioeng Biotechnol 2022; 9:804295. [PMID: 34993191 PMCID: PMC8724576 DOI: 10.3389/fbioe.2021.804295] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Accepted: 11/30/2021] [Indexed: 12/29/2022] Open
Abstract
Heterologous production of recombinant proteins is gaining increasing interest in biotechnology with respect to productivity, scalability, and wide applicability. The members of genus Streptomyces have been proposed as remarkable hosts for heterologous production due to their versatile nature of expressing various secondary metabolite biosynthetic gene clusters and secretory enzymes. However, there are several issues that limit their use, including low yield, difficulty in genetic manipulation, and their complex cellular features. In this review, we summarize rational engineering approaches to optimizing the heterologous production of secondary metabolites and recombinant proteins in Streptomyces species in terms of genetic tool development and chassis construction. Further perspectives on the development of optimal Streptomyces chassis by the design-build-test-learn cycle in systems are suggested, which may increase the availability of secondary metabolites and recombinant proteins.
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Affiliation(s)
- Soonkyu Hwang
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, South Korea.,KAIST Institute for the BioCentury, Korea Advanced Institute of Science and Technology, Daejeon, South Korea
| | - Yongjae Lee
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, South Korea.,KAIST Institute for the BioCentury, Korea Advanced Institute of Science and Technology, Daejeon, South Korea
| | - Ji Hun Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, South Korea.,KAIST Institute for the BioCentury, Korea Advanced Institute of Science and Technology, Daejeon, South Korea
| | - Gahyeon Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, South Korea.,KAIST Institute for the BioCentury, Korea Advanced Institute of Science and Technology, Daejeon, South Korea
| | - Hyeseong Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, South Korea.,KAIST Institute for the BioCentury, Korea Advanced Institute of Science and Technology, Daejeon, South Korea
| | - Woori Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, South Korea.,KAIST Institute for the BioCentury, Korea Advanced Institute of Science and Technology, Daejeon, South Korea
| | - Suhyung Cho
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, South Korea.,KAIST Institute for the BioCentury, Korea Advanced Institute of Science and Technology, Daejeon, South Korea
| | - Bernhard O Palsson
- Department of Bioengineering, University of California, San Diego, La Jolla, CA, United States.,Department of Pediatrics, University of California, San Diego, La Jolla, CA, United States.,Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Lyngby, Denmark
| | - Byung-Kwan Cho
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, South Korea.,KAIST Institute for the BioCentury, Korea Advanced Institute of Science and Technology, Daejeon, South Korea.,Innovative Biomaterials Research Center, KAIST Institutes, Korea Advanced Institute of Science and Technology, Daejeon, South Korea
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Anggraeni SR, Ansorge-Schumacher MB. Characterization and Modeling of Thermostable GH50 Agarases from Microbulbifer elongatus PORT2. MARINE BIOTECHNOLOGY (NEW YORK, N.Y.) 2021; 23:809-820. [PMID: 34595592 PMCID: PMC8551122 DOI: 10.1007/s10126-021-10065-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Accepted: 08/24/2021] [Indexed: 06/13/2023]
Abstract
Viewing the considerable potential of marine agar as a source for the sustainable production of energy as well as nature-derived pharmaceutics, this work investigated the catalytic activity of three novel GH50 agarases from the mesophilic marine bacterium Microbulbifer elongatus PORT2 isolated from Indonesian coastal seawaters. The GH50 agarases AgaA50, AgaB50, and AgaC50 were identified through genome analysis; the corresponding genes were cloned and expressed in Escherichia coli BL21 (DE3). All recombinant agarases hydrolyzed β-p-nitrophenyl galactopyranoside, indicating β-glycosidase characteristics. AgaA50 and AgaB50 were able to cleave diverse natural agar species derived from Indonesian agarophytes, indicating a promising tolerance of these enzymes for substrate modifications. All three GH50 agarases degraded agarose, albeit with remarkable diversity in their catalytic activity and mode of action. AgaA50 and AgaC50 exerted exolytic activity releasing differently sized neoagarobioses, while AgaB50 showed additional endolytic activity in dependence on the substrate size. Surprisingly, AgaA50 and AgaB50 revealed considerable thermostability, retaining over 75% activity after 1-h incubation at 50 °C. Considering the thermal properties of agar, this makes these enzymes promising candidates for industrial processing.
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Affiliation(s)
- Santi Rukminita Anggraeni
- Professur Für Molekulare Biotechnologie, Technische Universität Dresden, Dresden, 01062, Germany.
- Department of Marine Science, Faculty of Fisheries and Marine Science, Universitas Padjadjaran, Bandung, 45363, Indonesia.
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Jeon EJ, Choi JW, Cho MS, Jeong KJ. Enhanced production of neoagarobiose from agar with Corynebacterium glutamicum producing exo-type and endo-type β-agarases. Microb Biotechnol 2021; 14:2164-2175. [PMID: 34310855 PMCID: PMC8449658 DOI: 10.1111/1751-7915.13899] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Revised: 07/11/2021] [Accepted: 07/11/2021] [Indexed: 11/30/2022] Open
Abstract
Neoagarobiose (NA2) derived from agar marine biomass is a rare reagent that acts as an anti-melanogenesis reagent and moisturizer. Here, for the economical manufacturing of NA2, we developed the co-secretory production system of endo-type β-agarases (DagA) and exo-type β-agarases (EXB3) in Corynebacterium glutamicum. For this purpose, we first developed a secretory system of DagA via Tat pathway. To improve the secretion efficiency, we coexpressed two Tat pathway components (TatA and TatC), and to improve the purity of secreted DagA in the culture supernatant, two endogenous protein genes (Cg2052 and Cg1514) were removed. Using the engineered strain (C. glutamicum SP002), we confirmed that DagA as high as 1.53 g l-1 was successfully produced in the culture media with high purity (72.7% in the supernatant protein fraction). Next, we constructed the expression system (pHCP-CgR-DagA-EXB3) for the simultaneous secretion of EXB3 via Sec-pathway together with DagA, and it was clearly confirmed that DagA and EXB3 were successfully secreted as high as 54% and 24.5%, respectively. Finally, using culture medium containing DagA and EXB3, we successfully demonstrated the conversion of high-concentration agar (40 g l-1 ) into NA2 via a two-stage hydrolysis process.
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Affiliation(s)
- Eun Jung Jeon
- Department of Chemical and Biomolecular Engineering (BK Plus Program), Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 34141, Korea
| | - Jae Woong Choi
- Research Group of Traditional Food, Korea Food Research Institute, Wanju-gun, Jeollabuk-do, 55365, Korea
| | - Min Soo Cho
- Department of Chemical and Biomolecular Engineering (BK Plus Program), Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 34141, Korea
| | - Ki Jun Jeong
- Department of Chemical and Biomolecular Engineering (BK Plus Program), Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 34141, Korea.,Korea Advanced Institute of Science and Technology (KAIST), Institute for the BioCentury, 291 Daehak-ro, Yuseong-gu, Daejeon, 34141, Korea
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7
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Tsevelkhorloo M, Kim SH, Kang DK, Lee CR, Hong SK. NADP +-Dependent Dehydrogenase SCO3486 and Cycloisomerase SCO3480: Key Enzymes for 3,6-Anhydro-L-Galactose Catabolism in Streptomyces coelicolor A3(2). J Microbiol Biotechnol 2021; 31:756-763. [PMID: 33820885 PMCID: PMC9706016 DOI: 10.4014/jmb.2103.03030] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 03/30/2021] [Accepted: 04/05/2021] [Indexed: 12/15/2022]
Abstract
Agarose is a linear polysaccharide composed of D-galactose and 3,6-anhydro-L-galactose (AHG). It is a major component of the red algal cell wall and is gaining attention as an abundant marine biomass. However, the inability to ferment AHG is considered an obstacle in the large-scale use of agarose and could be addressed by understanding AHG catabolism in agarolytic microorganisms. Since AHG catabolism was uniquely confirmed in Vibrio sp. EJY3, a gram-negative marine bacterial species, we investigated AHG metabolism in Streptomyces coelicolor A3(2), an agarolytic gram-positive soil bacterium. Based on genomic data, the SCO3486 protein (492 amino acids) and the SCO3480 protein (361 amino acids) of S. coelicolor A3(2) showed identity with H2IFE7.1 (40% identity) encoding AHG dehydrogenase and H2IFX0.1 (42% identity) encoding 3,6-anhydro-L-galactonate cycloisomerase, respectively, which are involved in the initial catabolism of AHG in Vibrio sp. EJY3. Thin layer chromatography and mass spectrometry of the bioconversion products catalyzed by recombinant SCO3486 and SCO3480 proteins, revealed that SCO3486 is an AHG dehydrogenase that oxidizes AHG to 3,6-anhydro-L-galactonate, and SCO3480 is a 3,6-anhydro-L-galactonate cycloisomerase that converts 3,6-anhydro-L-galactonate to 2-keto-3-deoxygalactonate. SCO3486 showed maximum activity at pH 6.0 at 50°C, increased activity in the presence of iron ions, and activity against various aldehyde substrates, which is quite distinct from AHG-specific H2IFE7.1 in Vibrio sp. EJY3. Therefore, the catabolic pathway of AHG seems to be similar in most agar-degrading microorganisms, but the enzymes involved appear to be very diverse.
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Affiliation(s)
- Maral Tsevelkhorloo
- Department of Biosciences and Bioinformatics, Myongji University, Yongin 17058, Republic of Korea
| | - Sang Hoon Kim
- Department of Animal Resources Science, Dankook University, Cheonan 31116, Republic of Korea
| | - Dae-Kyung Kang
- Department of Animal Resources Science, Dankook University, Cheonan 31116, Republic of Korea
| | - Chang-Ro Lee
- Department of Biosciences and Bioinformatics, Myongji University, Yongin 17058, Republic of Korea
| | - Soon-Kwang Hong
- Department of Biosciences and Bioinformatics, Myongji University, Yongin 17058, Republic of Korea,Corresponding author Phone: 82-31-330-6198 Fax: 82-31-335-8249 E-mail:
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Jiang C, Cheng D, Liu Z, Sun J, Mao X. Advances in agaro-oligosaccharides preparation and bioactivities for revealing the structure-function relationship. Food Res Int 2021; 145:110408. [PMID: 34112411 DOI: 10.1016/j.foodres.2021.110408] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2020] [Revised: 04/13/2021] [Accepted: 05/06/2021] [Indexed: 11/24/2022]
Abstract
Agaro-oligosaccharides originating from red algae have attracted increasing attention in both basic theoretical research and applied fields due to their excellent bioactivities, which indicates the wide prospects of agaro-oligosaccharides for application in the food, pharmaceutical and cosmetic industries. Thus, a considerable number of studies regarding functional agaro-oligosaccharides preparation as well as the bioactivities exploration have been carried out. Based on these studies, this review first introduced different methods that have been used in agar extraction from red algae, and further provided research progress on arylsulfatase. Then, different methods used for agaro-oligosaccharides production were summarized. Moreover, the abundant bioactivities of agaro-oligosaccharides were described in detail. Finally, this review has discussed current research problems and further provided critical aspects, which may be helpful for revealing the structure-function relationship of agaro-oligosaccharide.
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Affiliation(s)
- Chengcheng Jiang
- College of Food Science and Engineering, Ocean University of China, Qingdao 266003, China
| | - Danyang Cheng
- College of Food Science and Engineering, Ocean University of China, Qingdao 266003, China
| | - Zhen Liu
- College of Food Science and Engineering, Ocean University of China, Qingdao 266003, China
| | - Jianan Sun
- College of Food Science and Engineering, Ocean University of China, Qingdao 266003, China.
| | - Xiangzhao Mao
- College of Food Science and Engineering, Ocean University of China, Qingdao 266003, China; Laboratory for Marine Drugs and Bioproducts of Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China
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Tsevelkhoroloo M, Shim SH, Lee CR, Hong SK, Hong YS. LacI-Family Transcriptional Regulator DagR Acts as a Repressor of the Agarolytic Pathway Genes in Streptomyces coelicolor A3(2). Front Microbiol 2021; 12:658657. [PMID: 33889146 PMCID: PMC8055832 DOI: 10.3389/fmicb.2021.658657] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Accepted: 03/08/2021] [Indexed: 11/15/2022] Open
Abstract
Actinobacteria utilize various polysaccharides in the soil as carbon source by degrading them via extracellular hydrolytic enzymes. Agarose, a marine algal polysaccharide composed of D-galactose and 3,6-anhydro-L-galactose (AHG), is one of the carbon sources used by S. coelicolor A3(2). However, little is known about agar hydrolysis in S. coelicolor A3(2), except that the regulation of agar hydrolysis metabolism is strongly inhibited by glucose as in the catabolic pathways of other polysaccharides. In this study, we elucidated the role of DagR in regulating the expression of three agarase genes (dagA, dagB, and dagC) in S. coelicolor A3(2) by developing a dagR-deletion mutant (Δsco3485). We observed that the Δsco3485 mutant had increased mRNA level of the agarolytic pathway genes and 1.3-folds higher agarase production than the wild type strain, indicating that the dagR gene encodes a cluster-suited repressor. Electrophoretic mobility shift assay revealed that DagR bound to the upstream regions of the three agarase genes. DNase 1 footprinting analysis demonstrated that a palindromic sequence present in the upstream region of the three agarase genes was essential for DagR-binding. Uniquely, the DNA-binding activity of DagR was inhibited by AHG, one of the final degradation products of agarose. AHG-induced agarase production was not observed in the Δsco3485 mutant, as opposed to that in the wild type strain. Therefore, DagR acts as a repressor that binds to the promoter region of the agarase genes, inhibits gene expression at the transcriptional level, and is derepressed by AHG. This is the first report on the regulation of gene expression regarding agar metabolism in S. coelicolor A3(2).
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Affiliation(s)
- Maral Tsevelkhoroloo
- Department of Bioscience and Bioinformatics, Myong-Ji University, Yongin-si, South Korea
| | - So Heon Shim
- Anticancer Agent Research Center, Korea Research Institute of Bioscience and Biotechnology, Cheongju-si, South Korea
| | - Chang-Ro Lee
- Department of Bioscience and Bioinformatics, Myong-Ji University, Yongin-si, South Korea
| | - Soon-Kwang Hong
- Department of Bioscience and Bioinformatics, Myong-Ji University, Yongin-si, South Korea
| | - Young-Soo Hong
- Anticancer Agent Research Center, Korea Research Institute of Bioscience and Biotechnology, Cheongju-si, South Korea
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10
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Park NJ, Yu S, Kim DH, Yun EJ, Kim KH. Characterization of BpGH16A of Bacteroides plebeius, a key enzyme initiating the depolymerization of agarose in the human gut. Appl Microbiol Biotechnol 2021; 105:617-625. [PMID: 33404831 DOI: 10.1007/s00253-020-11039-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Revised: 11/24/2020] [Accepted: 11/30/2020] [Indexed: 12/18/2022]
Abstract
Seaweeds have received considerable attention as sources of dietary fiber and biomass for manufacturing valuable products. The major polysaccharides of red seaweeds include agar and porphyran. In a marine environment, marine bacteria utilize agar and porphyran through the agarase and porphyranase genes encoded in their genomes. Most of these enzymes identified and characterized so far originate from marine bacteria. Recently, Bacteroides plebeius, a human gut bacterium isolated from seaweed-eating Japanese individuals, was revealed to contain a polysaccharide utilization locus (PUL) targeting the porphyran and agarose of red seaweeds. For example, B. plebeius contains an endo-type β-agarase, BpGH16A, belonging to glycoside hydrolase family 16. BpGH16A cleaves the β-1,4-glycosidic linkages of agarose and produces neoagarooligosccharides from agarose. Since it is crucial to study the characteristics of BpGH16A to understand the depolymerization pathway of red seaweed polysaccharides by B. plebeius in the human gut and to industrially apply the enzyme for the depolymerization of agar, we characterized BpGH16A for the first time. According to our results, BpGH16A is an extracellular endo-type β-agarase with an optimal temperature of 40 °C and an optimal pH of 7.0, which correspond to the temperature and pH of the human colon. BpGH16A depolymerizes agarose into neoagarotetraose (as the main product) and neoagarobiose (as the minor product). Thus, BpGH16A is suggested to be an important enzyme that initiates the depolymerization of red seaweed agarose or agar in the human gut by B. plebeius. KEY POINTS: • Bacteroides plebeius is a human gut bacterium isolated from seaweed-eating humans. • BpGH16A is an extracellular endo-type β-agarase with optimal conditions of 40 °C and pH 7.0. • BpGH16A depolymerizes agarose into neoagarotetraose and neoagarobiose.
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Affiliation(s)
- Na Jung Park
- Department of Biotechnology, Graduate School, Korea University, Seoul, 02841, South Korea
| | - Sora Yu
- Department of Biotechnology, Graduate School, Korea University, Seoul, 02841, South Korea
| | - Dong Hyun Kim
- Department of Biotechnology, Graduate School, Korea University, Seoul, 02841, South Korea
| | - Eun Ju Yun
- Department of Biotechnology, Graduate School, Korea University, Seoul, 02841, South Korea.
| | - Kyoung Heon Kim
- Department of Biotechnology, Graduate School, Korea University, Seoul, 02841, South Korea.
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Agarose degradation for utilization: Enzymes, pathways, metabolic engineering methods and products. Biotechnol Adv 2020; 45:107641. [PMID: 33035614 DOI: 10.1016/j.biotechadv.2020.107641] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Revised: 09/27/2020] [Accepted: 10/03/2020] [Indexed: 12/14/2022]
Abstract
Red algae are important renewable bioresources with very large annual outputs. Agarose is the major carbohydrate component of many red algae and has potential to be of value in the production of agaro-oligosaccharides, biofuels and other chemicals. In this review, we summarize the degradation pathway of agarose, which includes an upstream part involving transformation of agarose into its two monomers, D-galactose (D-Gal) and 3,6-anhydro-α-L-galactose (L-AHG), and a downstream part involving monosaccharide degradation pathways. The upstream part involves agarolytic enzymes such as α-agarase, β-agarase, α-neoagarobiose hydrolase, and agarolytic β-galactosidase. The downstream part includes the degradation pathways of D-Gal and L-AHG. In addition, the production of functional agaro-oligosaccharides such as neoagarobiose and monosaccharides such as L-AHG with different agarolytic enzymes is reviewed. Third, techniques for the setup, regulation and optimization of agarose degradation to increase utilization efficiency of agarose are summarized. Although heterologous construction of the whole agarose degradation pathway in an engineered strain has not been reported, biotechnologies applied to improve D-Gal utilization efficiency and construct L-AHG catalytic routes are reviewed. Finally, critical aspects that may aid in the construction of engineered microorganisms that can fully utilize agarose to produce agaro-oligosaccharides or as carbon sources for production of biofuels or other value-adding chemicals are discussed.
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Overexpression and characterization of a novel GH16 β-agarase (Aga1) from Cellulophaga omnivescoria W5C. Biotechnol Lett 2020; 42:2231-2238. [PMID: 32519168 DOI: 10.1007/s10529-020-02933-x] [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: 11/07/2019] [Accepted: 05/29/2020] [Indexed: 10/24/2022]
Abstract
OBJECTIVE To identify and characterize a new β-agarase from Cellulophaga omnivescoria W5C capable of producing biologically-active neoagarooligosaccharides from agar. RESULTS The β-agarase, Aga1, has signal peptides on both N- and C-terminals, which are involved in the type IX secretion system. It shares 75% protein sequence identity with AgaD from Zobellia galactanivorans and has a molecular weight of 54 kDa. Biochemical characterization reveals optimum agarolytic activities at pH 7-8 and temperature 30-45 °C. Aga1 retains at least 33% activity at temperatures lower than the sol-gel transition state of agarose. Metal ions are generally not essential, but calcium and potassium enhance its activity whereas iron and zinc are inhibitory. Finally, hydrolysis of agarose with Aga1 yields neoagarotetraose, neoagarohexaose, and neoagarooctaose. CONCLUSIONS Aga1 displays unique traits such as moderate psychrophilicity, stability, and synergy with other agarases, which makes it an excellent candidate for biosynthetic production of neoagarooligosaccharides from agar.
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Dual Agarolytic Pathways in a Marine Bacterium, Vibrio sp. Strain EJY3: Molecular and Enzymatic Verification. Appl Environ Microbiol 2020; 86:AEM.02724-19. [PMID: 31924614 DOI: 10.1128/aem.02724-19] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Accepted: 12/23/2019] [Indexed: 12/11/2022] Open
Abstract
Vibrio sp. strain EJY3 is an agarolytic marine bacterium that catabolizes 3,6-anhydro-l-galactose (AHG), a monomeric sugar unit of agarose. While the AHG catabolic pathway in EJY3 has been discovered recently, the complete agarolytic system of EJY3 remains unclear. We have identified five enzymes, namely, the β-agarases VejGH50A, VejGH50B, VejGH50C, and VejGH50D and the α-neoagarooligosaccharide (NAOS) hydrolase VejGH117, involved in the agarolytic system of EJY3. Based on the characterization of recombinant enzymes and intracellular metabolite analysis, we found that EJY3 catabolizes agarose via two different agarolytic pathways. Among the four β-agarases of EJY3, VejGH50A, VejGH50B, and VejGH50C were found to be extracellular agarases, producing mainly neoagarotetraose (NeoDP4) and neoagarobiose. By detecting intracellular NeoDP4 in EJY3 grown on agarose, NeoDP4 was observed being taken up by cells. Intriguingly, intracellular NeoDP4 acted as a branching point for the two different downstream agarolytic pathways. First, via the well-known agarolytic pathway, NeoDP4 was depolymerized into monomeric sugars by the exo-type β-agarase VejGH50D and the α-NAOS hydrolase VejGH117. Second, via the newly found alternative agarolytic pathway, NeoDP4 was depolymerized into AHG and agarotriose (AgaDP3) by VejGH117, and AgaDP3 then was completely depolymerized into monomeric sugars by sequential reactions of the agarolytic β-galactosidases (ABG) VejABG and VejGH117. Therefore, by experimentally verifying agarolytic enzymatic activity and transport of NeoDP4 into EJY3 cells, we revealed that EJY3 possesses both the known pathway and the newly discovered alternative pathway that involves α-NAOS hydrolase and ABG.IMPORTANCE Agarose is the main polysaccharide of red macroalgae and is composed of galactose and 3,6-anhydro-l-galactose. Many marine bacteria possess enzymes capable of depolymerizing agarose into oligomers and then depolymerizing the oligomers into monomers. Here, we experimentally verified that both a well-known agarolytic pathway and a novel agarolytic pathway exist in a marine bacterium, Vibrio sp. strain EJY3. In agarolytic pathways, agarose is depolymerized mainly into 4-sugar-unit oligomers by extracellular enzymes, which are then transported into cells. The imported oligomers are intracellularly depolymerized into galactose and 3,6-anhydro-l-galactose by two different agarolytic pathways, using different combinations of intracellular enzymes. These results elucidate the depolymerization routes of red macroalgal biomass in the ocean by marine bacteria and provide clues for developing industrial processes for efficiently producing sugars from red macroalgae.
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Jiang C, Liu Z, Sun J, Mao X. Characterization of a Novel α-Neoagarobiose Hydrolase Capable of Preparation of Medium- and Long-Chain Agarooligosaccharides. Front Bioeng Biotechnol 2020; 7:470. [PMID: 32064255 PMCID: PMC7000632 DOI: 10.3389/fbioe.2019.00470] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Accepted: 12/23/2019] [Indexed: 12/04/2022] Open
Abstract
α-Neoagarobiose hydrolase plays an important role in saccharification processes of marine biomass. In this study, an α-neoagarobiose hydrolase from Streptomyces coelicolor A3(2), designated as ScJC117, was identified, purified, and characterized. It has a sequence of 370 amino acids and belongs to the GH117 family. ScJC117 exhibited good activity under optimal hydrolysis conditions of pH 6.0 and 30°C, where it showed the Km and kcat for neoagarobiose of 11.57 mM and 0.48 s–1, respectively. ScJC117 showed the ability to hydrolyze neoagarooligosaccharides with the polymerization degrees of 2–14. A basis of catalytic activity toward the first α-1,3-glycosidic bond of the neoagarooligosaccharides from the non-reducing end, ScJC117 can be classified as an exo-type α-neoagarobiose hydrolase. These results suggested that ScJC117 could be used in the preparation of odd agarooligosaccharides (especially agaroheptaose-agaroundecaose) and 3,6-anhydro-L-galactose, which has a functional food additive potential. Moreover, ScJC117 can be used for comprehensive utilization of red algae.
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Affiliation(s)
- Chengcheng Jiang
- College of Food Science and Engineering, Ocean University of China, Qingdao, China
| | - Zhen Liu
- College of Food Science and Engineering, Ocean University of China, Qingdao, China
| | - Jianan Sun
- College of Food Science and Engineering, Ocean University of China, Qingdao, China
| | - Xiangzhao Mao
- College of Food Science and Engineering, Ocean University of China, Qingdao, China.,Laboratory for Marine Drugs and Bioproducts of Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
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Chi WJ, Seo JW, Hong SK. Characterization of Two Thermostable β-agarases from a Newly Isolated Marine Agarolytic Bacterium, Vibrio sp. S1. BIOTECHNOL BIOPROC E 2019. [DOI: 10.1007/s12257-019-0180-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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Lee CH, Lee CR, Hong SK. Biochemical characterization of a novel cold-adapted agarotetraose-producing α-agarase, AgaWS5, from Catenovulum sediminis WS1-A. Appl Microbiol Biotechnol 2019; 103:8403-8411. [PMID: 31375882 DOI: 10.1007/s00253-019-10056-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Revised: 07/21/2019] [Accepted: 07/26/2019] [Indexed: 11/27/2022]
Abstract
Although many β-agarases that hydrolyze the β-1,4 linkages of agarose have been biochemically characterized, only three α-agarases that hydrolyze the α-1,3 linkages are reported to date. In this study, a new α-agarase, AgaWS5, from Catenovulum sediminis WS1-A, a new agar-degrading marine bacterium, was biochemically characterized. AgaWS5 belongs to the glycoside hydrolase (GH) 96 family. AgaWS5 consists of 1295 amino acids (140 kDa) and has the 65% identity to an α-agarase, AgaA33, obtained from an agar-degrading bacterium Thalassomonas agarivorans JAMB-A33. AgaWS5 showed the maximum activity at a pH and temperature of 8 and 40 °C, respectively. AgaWS5 showed a cold-tolerance, and it retained more than 40% of its maximum enzymatic activity at 10 °C. AgaWS5 is predicted to have several calcium-binding sites. Thus, its activity was slightly enhanced in the presence of Ca2+, and was strongly inhibited by EDTA. The Km and Vmax of AgaWS5 for agarose were 10.6 mg/mL and 714.3 U/mg, respectively. Agarose-liquefication, thin layer chromatography, and mass and NMR spectroscopic analyses demonstrated that AgaWS5 is an endo-type α-agarase that degrades agarose and mainly produces agarotetraose. Thus, in this study, a novel cold-adapted GH96 agarotetraose-producing α-agarase was identified.
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Affiliation(s)
- Choong Hyun Lee
- Department of Biological Sciences, Myongji University, Yongin, Gyeonggido, 449-728, Republic of Korea
| | - Chang-Ro Lee
- Department of Biological Sciences, Myongji University, Yongin, Gyeonggido, 449-728, Republic of Korea
| | - Soon-Kwang Hong
- Department of Biological Sciences, Myongji University, Yongin, Gyeonggido, 449-728, Republic of Korea.
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Safety evaluation of β-agarase preparations from Streptomyces coelicolor A3(2). Regul Toxicol Pharmacol 2019; 101:142-155. [DOI: 10.1016/j.yrtph.2018.11.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Revised: 11/05/2018] [Accepted: 11/12/2018] [Indexed: 12/27/2022]
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Veerakumar S, Manian RP. Recombinant β-agarases: insights into molecular, biochemical, and physiochemical characteristics. 3 Biotech 2018; 8:445. [PMID: 30333947 DOI: 10.1007/s13205-018-1470-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Accepted: 10/03/2018] [Indexed: 12/11/2022] Open
Abstract
Agarases (agarose 4-glycanohydrolase; EC 3.2.1.81) are class of enzymes that belong to glycoside hydrolase (GH) family capable of hydrolyzing agar. Their classification depends on hydrolysis pattern and product formation. Among all the agarases, β-agarases and the oligosaccharides formed by its action have fascinated quite a lot of industries. Ample of β-agarase genes have been endowed from marine sources such as algae, sea water, and marine sediments, and the expression of these genes into suitable host gives rise to recombinant β-agarases. These recombinant β-agarases have wide range of industrial applications due to its improved catalytic efficiency and stability in tough environments with ease of production on large scale. In this review, we have perused different types of recombinant β-agarases in consort with their molecular, physiochemical, and kinetic properties in detail and the significant features of those agarases are spotlighted. From the literature reviewed after 2010, we have found that the recombinant β-agarases belonged to the families GH16, GH39, GH50, GH86, and GH118. Among that, GH39, GH50, and GH86 belonged to clan GH-A, while the GH16 family belonged to clan GH-B. It was observed that GH16 is the largest polyspecific glycoside hydrolase family with ample number of β-agarases and the families GH50 and GH118 were found to be monospecific with only β-agarase activity. And, out of 84 non-catalytic carbohydrate-binding modules (CBMs), only CBM6 and CBM13 were professed in β-agarases. We witnessed a larger heterogeneity in molecular, physiochemical, and catalytic characteristics of the recombinant β-agarases including molecular mass: 32-132 kDa, optimum pH: 4.5-9, optimum temperature 16-60 °C, K M: 0.68-59.8 mg/ml, and V max: 0.781-11,400 U/mg. Owing to this extensive range of heterogeneity, they have lion's share in the multibillion dollar enzyme market. This review provides a holistic insight to a few aspects of recombinant β-agarases which can be referred by the upcoming explorers to this area.
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Affiliation(s)
- Sneeha Veerakumar
- Department of Biotechnology, School of Bio Sciences and Technology, Vellore Institute of Technology (VIT), Vellore, 632014 India
| | - Ramesh Pathy Manian
- Department of Biotechnology, School of Bio Sciences and Technology, Vellore Institute of Technology (VIT), Vellore, 632014 India
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Oligosaccharides Derived from Red Seaweed: Production, Properties, and Potential Health and Cosmetic Applications. Molecules 2018; 23:molecules23102451. [PMID: 30257445 PMCID: PMC6222765 DOI: 10.3390/molecules23102451] [Citation(s) in RCA: 84] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Revised: 09/17/2018] [Accepted: 09/21/2018] [Indexed: 12/30/2022] Open
Abstract
Because of their potential use as functional ingredients in human nutrition, oligosaccharides derived from natural sources are receiving paramount consideration. Red seaweed, a proven rich source of agar and carrageenan, is one of the most abundantly present sources of such oligosaccharides. Agaro-oligosaccharides (AOS) and carrageenan-oligosaccharides (COS) are produced from agar and carrageenan, respectively, through chemical and enzymatic hydrolyses. Enzymatic hydrolysis of agar and carrageenan into oligosaccharides is preferred in industrial production because of certain problems associated with chemical hydrolysis, including the release of high amounts of monosaccharides and undesirable toxic products, such as furfural. AOS and COS possess many biological activities, including prebiotic, immuno-modulatory, anti-oxidant, and anti-tumor activities. These activities are related to their chemical structure, molecular weight, degree of polymerization, and the flexibility of the glycosidic linkages. Therefore, the structure–function relationship and the mechanisms occurring during the specific biological applications of AOS and COS are discussed herein. Moreover, the chromatographic separation, purification, and characterization of AOS and COS are also part of this review. This piece of writing strives to create a new perspective on the potential applications of AOS and COS in the functional food and pharmaceutical industry.
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Combined Drug Resistance Mutations Substantially Enhance Enzyme Production in Paenibacillus agaridevorans. J Bacteriol 2018; 200:JB.00188-18. [PMID: 29866810 DOI: 10.1128/jb.00188-18] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Accepted: 05/29/2018] [Indexed: 11/20/2022] Open
Abstract
This study shows that sequential introduction of drug resistance mutations substantially increased enzyme production in Paenibacillus agaridevorans The triple mutant YT478 (rsmG Gln225→stop codon, rpsL K56R, and rpoB R485H), generated by screening for resistance to streptomycin and rifampin, expressed a 1,100-fold-larger amount of the extracellular enzyme cycloisomaltooligosaccharide glucanotransferase (CITase) than the wild-type strain. These mutants were characterized by higher intracellular S-adenosylmethionine concentrations during exponential phase and enhanced protein synthesis activity during stationary phase. Surprisingly, the maximal expression of CITase mRNA was similar in the wild-type and triple mutant strains, but the mutant showed greater CITase mRNA expression throughout the growth curve, resulting in enzyme overproduction. A metabolome analysis showed that the triple mutant YT478 had higher levels of nucleic acids and glycolysis metabolites than the wild type, indicating that YT478 mutant cells were activated. The production of CITase by the triple mutant was further enhanced by introducing a mutation conferring resistance to the rare earth element, scandium. This combined drug resistance mutation method also effectively enhanced the production of amylases, proteases, and agarases by P. agaridevorans and Streptomyces coelicolor This method also activated the silent or weak expression of the P. agaridevorans CITase gene, as shown by comparisons of the CITase gene loci of P. agaridevorans T-3040 and another cycloisomaltooligosaccharide-producing bacterium, Paenibacillus sp. strain 598K. The simplicity and wide applicability of this method should facilitate not only industrial enzyme production but also the identification of dormant enzymes by activating the expression of silent or weakly expressed genes.IMPORTANCE Enzyme use has become more widespread in industry. This study evaluated the molecular basis and effectiveness of ribosome engineering in markedly enhancing enzyme production (>1,000-fold). This method, due to its simplicity, wide applicability, and scalability for large-scale production, should facilitate not only industrial enzyme production but also the identification of novel enzymes, because microorganisms contain many silent or weakly expressed genes which encode novel antibiotics or enzymes. Furthermore, this study provides a new mechanism for strain improvement, with a consistent rather than transient high expression of the key gene(s) involved in enzyme production.
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Lee MH, Jang JH, Yoon GY, Lee SJ, Lee MG, Kang TH, Han HD, Kim HS, Choi WS, Park WS, Park YM, Jung ID. Neoagarohexaose-mediated activation of dendritic cells via Toll-like receptor 4 leads to stimulation of natural killer cells and enhancement of antitumor immunity. BMB Rep 2018; 50:263-268. [PMID: 28287066 PMCID: PMC5458676 DOI: 10.5483/bmbrep.2017.50.5.014] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2017] [Indexed: 01/01/2023] Open
Abstract
β-Agarase cleaves the β-1,4 linkages of agar to produce neoagarooligosaccharides (NAO), which are associated with various physiological functions. However, the immunological functions of NAO are still unclear. In this study, we demonstrated that β-agarase DagA-produced neoagarohexaose (DP6), an NAO product, promoted the maturation of dendritic cells (DCs) by Toll-like receptor 4 (TLR4). DP6 directly and indirectly enhanced the activation of natural killer (NK) cells in a TLR4-dependent manner in vitro and in vivo. Finally, the antitumor activity of DP6 against B16F1 melanoma cells was inhibited in NK cell-depletion systems by using NK-cell depleting antibodies in vivo. Collectively, the results indicated that DP6 augments antitumor immunity against B16F1 melanoma cells via the activation of DC-mediated NK cells in a TLR4-dependent manner. Thus, DP6 is a potential candidate adjuvant that acts as an immune cell modulator for the treatment of melanoma. [BMB Reports 2017; 50(5): 263-268].
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Affiliation(s)
- Moon Hee Lee
- Department of Immunology, Laboratory of Dendritic Cell Differentiation and Regulation, School of Medicine, Konkuk University, Chungju 27478, Korea
| | - Jong-Hwa Jang
- Department of Dental Hygiene, Hanseo University, Seosan 31962, Korea
| | - Gun Young Yoon
- Department of Immunology, Laboratory of Dendritic Cell Differentiation and Regulation, School of Medicine, Konkuk University, Chungju 27478, Korea
| | - Seung Jun Lee
- Department of Immunology, Laboratory of Dendritic Cell Differentiation and Regulation, School of Medicine, Konkuk University, Chungju 27478, Korea
| | - Min-Goo Lee
- Department of Physiology, Korea University, College of Medicine, Seoul 02841, Korea
| | - Tae Heung Kang
- Department of Immunology, Laboratory of Dendritic Cell Differentiation and Regulation, School of Medicine, Konkuk University, Chungju 27478, Korea
| | - Hee Dong Han
- Department of Immunology, Laboratory of Dendritic Cell Differentiation and Regulation, School of Medicine, Konkuk University, Chungju 27478, Korea
| | - Hyuk Soon Kim
- Department of Immunology, Laboratory of Dendritic Cell Differentiation and Regulation, School of Medicine, Konkuk University, Chungju 27478, Korea
| | - Wahn Soo Choi
- Department of Immunology, Laboratory of Dendritic Cell Differentiation and Regulation, School of Medicine, Konkuk University, Chungju 27478, Korea
| | - Won Sun Park
- Institute of Medical Sciences, Department of Physiology, Kangwon National University School of Medicine, Chuncheon 24341, Korea
| | - Yeong-Min Park
- Department of Immunology, Laboratory of Dendritic Cell Differentiation and Regulation, School of Medicine, Konkuk University, Chungju 27478, Korea
| | - In Duk Jung
- Department of Immunology, Laboratory of Dendritic Cell Differentiation and Regulation, School of Medicine, Konkuk University, Chungju 27478, Korea
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Wang Y, Liu T, Guo S, Zhang P, Sun P, Chen M, Ming H. Characterization and overexpression of a glycosyl hydrolase family 16 β-agarase Aga0917 from Pseudoalteromonas fuliginea YTW1-15-1. J GEN APPL MICROBIOL 2018; 64:276-283. [DOI: 10.2323/jgam.2018.02.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Yan Wang
- Synthetic Biology Engineering Lab of Henan Province, School of Life Sciences and Technology, Xinxiang Medical University
| | - Tingwei Liu
- Synthetic Biology Engineering Lab of Henan Province, School of Life Sciences and Technology, Xinxiang Medical University
| | - Shuai Guo
- Synthetic Biology Engineering Lab of Henan Province, School of Life Sciences and Technology, Xinxiang Medical University
| | - Peng Zhang
- Synthetic Biology Engineering Lab of Henan Province, School of Life Sciences and Technology, Xinxiang Medical University
| | - Pengyang Sun
- Synthetic Biology Engineering Lab of Henan Province, School of Life Sciences and Technology, Xinxiang Medical University
| | - Mengqian Chen
- Synthetic Biology Engineering Lab of Henan Province, School of Life Sciences and Technology, Xinxiang Medical University
| | - Hong Ming
- Synthetic Biology Engineering Lab of Henan Province, School of Life Sciences and Technology, Xinxiang Medical University
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An K, Shi X, Cui F, Cheng J, Liu N, Zhao X, Zhang XH. Characterization and overexpression of a glycosyl hydrolase family 16 beta-agarase YM01-1 from marine bacterium Catenovulum agarivorans YM01 T. Protein Expr Purif 2017; 143:1-8. [PMID: 28986239 DOI: 10.1016/j.pep.2017.10.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Revised: 09/20/2017] [Accepted: 10/01/2017] [Indexed: 10/18/2022]
Abstract
Agar, usually extracted from seaweed, has a wide variety of industrial applications due to its gelling and stabilizing characteristics. Agarases are the enzymes which hydrolyze agar into agar oligosaccharides. The produced agar oligosaccharides have been widely used in cosmetic, food, and medical fields due to their biological functions. A beta-agarase gene, YM01-1, was cloned and expressed from a marine bacterium Catenovulum agarivorans YM01T. The encoding agarase of YM01-1 consisted of 331 amino acids with an apparent molecular mass of 37.7 kDa and a 23-amino-acids signal peptide. YM01-1 belongs to glycoside hydrolase 16 (GH16) family based on the amino acid sequence homology. The optimum pH and temperature for its activity was 7.0 and 50 °C, respectively. YM01-1 was stable at a pH of pH 6.0-9.0 and temperatures below 45 °C. Thin layer chromatography (TLC) and ion trap mass spectrometer of the YM01-1 hydrolysis products displayed that YM01-1 was an endo-type β-agarase and degrades agarose, neoagarohexaose, neoagarotetraose into neoagarobiose. The Km, Vmax, Kcat and Kcat/Km values of the YM01-1 for agarose were 8.69 mg/ml, 4.35 × 103 U/mg, 2.4 × 103 s-1 and 2.7 × 106 s-1 M-1, respectively. Hence, the enzyme with high agarolytic activity and single end product was different from other GH16 agarases, which has potential applications for the production of oligosaccharides with remarkable activities.
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Affiliation(s)
- Ke An
- College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China
| | - Xiaochong Shi
- College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China.
| | - Fangyuan Cui
- College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China
| | - Jingguang Cheng
- College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China
| | - Na Liu
- College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China
| | - Xia Zhao
- School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, China
| | - Xiao-Hua Zhang
- College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China
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Ramos KRM, Valdehuesa KNG, Nisola GM, Lee WK, Chung WJ. Identification and characterization of a thermostable endolytic β-agarase Aga2 from a newly isolated marine agarolytic bacteria Cellulophaga omnivescoria W5C. N Biotechnol 2017; 40:261-267. [PMID: 28962879 DOI: 10.1016/j.nbt.2017.09.006] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Revised: 08/22/2017] [Accepted: 09/25/2017] [Indexed: 12/21/2022]
Abstract
Research on the enzymatic breakdown of seaweed-derived agar has recently gained attention due to the progress in green technologies for marine biomass utilization. The enzymes known as agarases catalyze the cleavage of glycosidic bonds within the polysaccharide. In this study, a new β-agarase, Aga2, was identified from Cellulophaga omnivescoria W5C. Aga2 is one of four putative agarases from the W5C genome, and it belongs to the glycoside hydrolase 16 family. It was shown to be exclusive to the Cellulophaga genus. Agarase activity assays showed that Aga2 is an endolytic-type β-agarase that produces tetrameric and hexameric neoagaro-oligosaccharides, with optimum activity at 45°C and pH 8.0. Zinc ions slightly enhanced its activity while manganese ions had inhibitory effects even at very low concentrations. Aga2 has a Km of 2.59mgmL-1 and Vmax of 275.48Umg-1. The Kcat is 1.73×102s-1, while the Kcat/Km is 8.04×106s-1M-1. Aga2 also showed good thermostability at 45°C and above, and retained >90% of its activity after repeated freeze-thaw cycles. Bioinformatic analysis of its amino acid sequence revealed that intrinsic properties of the protein (e.g. presence of certain dipeptides and the relative volume occupied by aliphatic amino acids) and tertiary structural elements (e.g. presence of salt bridges, hydrophobic interactions and H-bonding) contributed to its thermostability.
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Affiliation(s)
- Kristine Rose M Ramos
- Energy and Environment Fusion Technology Center (E(2)FTC), Department of Energy Science and Technology (DEST), Myongji University, Yongin-si, Gyeonggi-do, Republic of Korea
| | - Kris Niño G Valdehuesa
- Energy and Environment Fusion Technology Center (E(2)FTC), Department of Energy Science and Technology (DEST), Myongji University, Yongin-si, Gyeonggi-do, Republic of Korea
| | - Grace M Nisola
- Energy and Environment Fusion Technology Center (E(2)FTC), Department of Energy Science and Technology (DEST), Myongji University, Yongin-si, Gyeonggi-do, Republic of Korea
| | - Won-Keun Lee
- Division of Bioscience and Bioinformatics, Myongji University, Yongin-si, Gyeonggi-do, Republic of Korea.
| | - Wook-Jin Chung
- Energy and Environment Fusion Technology Center (E(2)FTC), Department of Energy Science and Technology (DEST), Myongji University, Yongin-si, Gyeonggi-do, Republic of Korea.
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In vitro and in vivo investigation for biological activities of neoagarooligosaccharides prepared by hydrolyzing agar with β-agarase. BIOTECHNOL BIOPROC E 2017. [DOI: 10.1007/s12257-017-0049-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Hong SJ, Lee JH, Kim EJ, Yang HJ, Park JS, Hong SK. Toxicological evaluation of neoagarooligosaccharides prepared by enzymatic hydrolysis of agar. Regul Toxicol Pharmacol 2017; 90:9-21. [PMID: 28782575 DOI: 10.1016/j.yrtph.2017.08.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Revised: 07/31/2017] [Accepted: 08/01/2017] [Indexed: 10/19/2022]
Abstract
Agar, a heterogeneous polymer of galactose, is the main component of the cell wall of marine red algae. It is well established as a safe, non-digestible carbohydrate in Oriental countries. Although neoagarooligosaccharides (NAOs) prepared by the hydrolysis of agar by β-agarase have been reported to exert various biological activities, the safety of these compounds has not been reported to date. For safety evaluation, NAOs containing mainly neoagarotetraose and neoagarohexaose were prepared from agar by enzymatic hydrolysis using β-agarase DagA from Streptomyces coelicolor. Genotoxicity tests such as the bacterial reverse mutation assay, eukaryotic chromosome aberration assay, and in vivo micronucleus assay all indicated that NAOs did not exert any mutational effects. The toxicity of NAOs in rat and beagle dog models was investigated by acute, 14-day, and 91-day repeated oral dose toxicity tests. The results showed that NAO intake of up to 5,000 mg/kg body weight resulted in no significant changes in body weight, food intake, water consumption, hematologic and blood biochemistry parameters, organ weight, or clinical symptoms. Collectively, a no-observed-adverse-effect level of 5,000 mg/kg body weight/day for both male and female rats was established for NAO. These findings support the safety of NAO for possible use in food supplements and pharmaceutical and cosmetic products.
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Affiliation(s)
- Sun Joo Hong
- Department of Biological Science and Bioinformatics, Myongji University, 116 Myongji-Ro, Cheoin-gu, Yongin, Gyeonggido 17058, Republic of Korea; Dynebio Inc., B-B205 Woolimlions Valley II, 45 Sagimagil-Ro, Jungwon-Gu, Seongnam-Si, Gyeonggi-Do 13209, Republic of Korea
| | - Je-Hyeon Lee
- Dynebio Inc., B-B205 Woolimlions Valley II, 45 Sagimagil-Ro, Jungwon-Gu, Seongnam-Si, Gyeonggi-Do 13209, Republic of Korea
| | - Eun Joo Kim
- Dynebio Inc., B-B205 Woolimlions Valley II, 45 Sagimagil-Ro, Jungwon-Gu, Seongnam-Si, Gyeonggi-Do 13209, Republic of Korea
| | - Hea Jung Yang
- Dynebio Inc., B-B205 Woolimlions Valley II, 45 Sagimagil-Ro, Jungwon-Gu, Seongnam-Si, Gyeonggi-Do 13209, Republic of Korea
| | - Jae-Seon Park
- Department of Biological Science and Bioinformatics, Myongji University, 116 Myongji-Ro, Cheoin-gu, Yongin, Gyeonggido 17058, Republic of Korea
| | - Soon-Kwang Hong
- Department of Biological Science and Bioinformatics, Myongji University, 116 Myongji-Ro, Cheoin-gu, Yongin, Gyeonggido 17058, Republic of Korea.
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Harvey DJ. Analysis of carbohydrates and glycoconjugates by matrix-assisted laser desorption/ionization mass spectrometry: An update for 2011-2012. MASS SPECTROMETRY REVIEWS 2017; 36:255-422. [PMID: 26270629 DOI: 10.1002/mas.21471] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2014] [Accepted: 01/15/2015] [Indexed: 06/04/2023]
Abstract
This review is the seventh update of the original article published in 1999 on the application of MALDI mass spectrometry to the analysis of carbohydrates and glycoconjugates and brings coverage of the literature to the end of 2012. General aspects such as theory of the MALDI process, matrices, derivatization, MALDI imaging, and fragmentation are covered in the first part of the review and applications to various structural types constitute the remainder. The main groups of compound are oligo- and poly-saccharides, glycoproteins, glycolipids, glycosides, and biopharmaceuticals. Much of this material is presented in tabular form. Also discussed are medical and industrial applications of the technique, studies of enzyme reactions, and applications to chemical synthesis. © 2015 Wiley Periodicals, Inc. Mass Spec Rev 36:255-422, 2017.
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Affiliation(s)
- David J Harvey
- Department of Biochemistry, Oxford Glycobiology Institute, University of Oxford, Oxford, OX1 3QU, UK
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Hong SJ, Lee JH, Kim EJ, Yang HJ, Park JS, Hong SK. Anti-Obesity and Anti-Diabetic Effect of Neoagarooligosaccharides on High-Fat Diet-Induced Obesity in Mice. Mar Drugs 2017; 15:md15040090. [PMID: 28333098 PMCID: PMC5408236 DOI: 10.3390/md15040090] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Revised: 03/09/2017] [Accepted: 03/16/2017] [Indexed: 02/06/2023] Open
Abstract
Neoagarooligosaccharides (NAOs), mainly comprising neoagarotetraose and neoagarohexaose, were prepared by hydrolyzing agar with β-agarase DagA from Streptomyces coelicolor, and the anti-obesity and anti-diabetic effects of NAOs on high-fat diet (HFD)-induced obesity in mice were investigated after NAOs-supplementation for 64 days. Compared to the HFD group, the HFD-0.5 group that was fed with HFD + NAOs (0.5%, w/w) showed remarkable reduction of 36% for body weight gain and 37% for food efficiency ratios without abnormal clinical signs. Furthermore, fat accumulation in the liver and development of macrovesicular steatosis induced by HFD in the HFD-0.5 group were recovered nearly to the levels found in the normal diet (ND) group. NAOs intake could also effectively reduce the size (area) of adipocytes and tissue weight gain in the perirenal and epididymal adipose tissues. The increased concentrations of total cholesterol, triglyceride, and free fatty acid in serum of the HFD group were also markedly ameliorated to the levels found in serum of the ND group after NAOs-intake in a dose dependent manner. In addition, insulin resistance and glucose intolerance induced by HFD were distinctly improved, and adiponectin concentration in the blood was notably increased. All these results strongly suggest that intake of NAOs can effectively suppress obesity and obesity-related metabolic syndromes, such as hyperlipidemia, steatosis, insulin resistance, and glucose intolerance, by inducing production of adiponectin in the HFD-induced obese mice.
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Affiliation(s)
- Sun Joo Hong
- Department of Biological Science and Bioinformatics, Myongji University, 116 Myongji-Ro, Cheoin-gu, Yongin, Gyeonggido 17058, Korea.
- Dynebio Inc., B-B205 Woolimlions Valley II, 45 Sagimagil-Ro, Jungwon-Gu, Seongnam-Si, Gyeonggi-Do 13209, Korea.
| | - Je-Hyeon Lee
- Dynebio Inc., B-B205 Woolimlions Valley II, 45 Sagimagil-Ro, Jungwon-Gu, Seongnam-Si, Gyeonggi-Do 13209, Korea.
| | - Eun Joo Kim
- Dynebio Inc., B-B205 Woolimlions Valley II, 45 Sagimagil-Ro, Jungwon-Gu, Seongnam-Si, Gyeonggi-Do 13209, Korea.
| | - Hea Jung Yang
- Dynebio Inc., B-B205 Woolimlions Valley II, 45 Sagimagil-Ro, Jungwon-Gu, Seongnam-Si, Gyeonggi-Do 13209, Korea.
| | - Jae-Seon Park
- Department of Biological Science and Bioinformatics, Myongji University, 116 Myongji-Ro, Cheoin-gu, Yongin, Gyeonggido 17058, Korea.
| | - Soon-Kwang Hong
- Department of Biological Science and Bioinformatics, Myongji University, 116 Myongji-Ro, Cheoin-gu, Yongin, Gyeonggido 17058, Korea.
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Wang W, Liu P, Hao C, Wu L, Wan W, Mao X. Neoagaro-oligosaccharide monomers inhibit inflammation in LPS-stimulated macrophages through suppression of MAPK and NF-κB pathways. Sci Rep 2017; 7:44252. [PMID: 28266652 PMCID: PMC5339798 DOI: 10.1038/srep44252] [Citation(s) in RCA: 68] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Accepted: 02/06/2017] [Indexed: 12/22/2022] Open
Abstract
Neoagaro-oligosaccharides derived from agarose have been demonstrated to possess a variety of biological activities, such as anti-bacteria and anti-oxidative activities. In this study, we mainly explored the inhibitory effects and the mechanisms of neoagaro-oligosaccharide monomers against LPS-induced inflammatory responses in mouse macrophage RAW264.7 cells. The results indicated that neoagaro-oligosaccharide monomers especially neoagarotetraose could significantly reduce the production and release of NO in LPS-induced macrophages. Neoagarotetraose significantly suppressed the expression and secretion of inducible nitric oxide synthase (iNOS) and proinflammatory cytokines such as TNF-α and IL-6. The inhibition mechanisms may be associated with the inhibition of the activation of p38MAPK, Ras/MEK/ERK and NF-κB signaling pathways. Thus, neoagarotetraose may attenuate the inflammatory responses through downregulating the MAPK and NF-κB signaling pathways in LPS-stimulated macrophages. In summary, the marine-derived neoagaro-oligosaccharide monomers merit further investigation as novel anti-inflammation agents in the future.
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Affiliation(s)
- Wei Wang
- College of Food Science and Engineering, and School of Medicine and Pharmacy, Ocean University of China, Qingdao, 266003, China
| | - Pei Liu
- College of Food Science and Engineering, and School of Medicine and Pharmacy, Ocean University of China, Qingdao, 266003, China
| | - Cui Hao
- Institute of Cerebrovascular Diseases, Affiliated Hospital of Qingdao University Medical College, Qingdao, 266003, China
| | - Lijuan Wu
- College of Food Science and Engineering, and School of Medicine and Pharmacy, Ocean University of China, Qingdao, 266003, China
| | - Wenjin Wan
- Department of Biology, Hong Kong Baptist University, Hong Kong, China
| | - Xiangzhao Mao
- College of Food Science and Engineering, and School of Medicine and Pharmacy, Ocean University of China, Qingdao, 266003, China
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Lin B, Liu Y, Lu G, Zhao M, Hu Z. An agarase of glycoside hydrolase family 16 from marine bacterium Aquimarina agarilytica ZC1. FEMS Microbiol Lett 2017; 364:2996628. [DOI: 10.1093/femsle/fnx012] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2016] [Accepted: 01/13/2017] [Indexed: 11/14/2022] Open
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Xiao Q, Yin Q, Ni H, Cai H, Wu C, Xiao A. Characterization and immobilization of arylsulfatase on modified magnetic nanoparticles for desulfation of agar. Int J Biol Macromol 2017; 94:576-584. [DOI: 10.1016/j.ijbiomac.2016.10.029] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2016] [Revised: 10/08/2016] [Accepted: 10/11/2016] [Indexed: 11/26/2022]
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Xiao A, Xiao Q, Lin Y, Ni H, Zhu Y, Cai H. Efficient immobilization of agarase using carboxyl-functionalized magnetic nanoparticles as support. ELECTRON J BIOTECHN 2017. [DOI: 10.1016/j.ejbt.2016.10.007] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
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Biochemical characterization of a novel cold-adapted GH39 β-agarase, AgaJ9, from an agar-degrading marine bacterium Gayadomonas joobiniege G7. Appl Microbiol Biotechnol 2016; 101:1965-1974. [DOI: 10.1007/s00253-016-7951-4] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Revised: 10/11/2016] [Accepted: 10/20/2016] [Indexed: 11/28/2022]
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Cloning, Expression, and Biochemical Characterization of a Novel Acidic GH16 β-Agarase, AgaJ11, from Gayadomonas joobiniege G7. Appl Biochem Biotechnol 2016; 181:961-971. [DOI: 10.1007/s12010-016-2262-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Accepted: 09/19/2016] [Indexed: 11/30/2022]
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35
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Kim JH, Yun EJ, Seo N, Yu S, Kim DH, Cho KM, An HJ, Kim JH, Choi IG, Kim KH. Enzymatic liquefaction of agarose above the sol–gel transition temperature using a thermostable endo-type β-agarase, Aga16B. Appl Microbiol Biotechnol 2016; 101:1111-1120. [DOI: 10.1007/s00253-016-7831-y] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2016] [Revised: 08/14/2016] [Accepted: 08/21/2016] [Indexed: 11/30/2022]
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Isolation and Characterization of a Glycosyl Hydrolase Family 16 β-Agarase from a Mangrove Soil Metagenomic Library. Int J Mol Sci 2016; 17:ijms17081360. [PMID: 27548158 PMCID: PMC5000755 DOI: 10.3390/ijms17081360] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Revised: 07/28/2016] [Accepted: 08/15/2016] [Indexed: 11/17/2022] Open
Abstract
A mangrove soil metagenomic library was constructed and a β-agarase gene designated as AgaML was isolated by functional screening. The gene encoded for a 659-amino-acids polypeptide with an estimated molecular mass of 71.6 kDa. The deduced polypeptide sequences of AgaML showed the highest identity of 73% with the glycoside hydrolase family 16 β-agarase from Microbulbifer agarilyticus in the GenBank database. AgaML was cloned and highly expressed in Escherichia coli BL21(DE3). The purified recombinant protein, AgaML, showed optimal activity at 50 °C and pH 7.0. The kinetic parameters of Km and Vmax values toward agarose were 4.6 mg·mL(-1) and 967.5 μM·min(-1)·mg(-1), respectively. AgaML hydrolyzed the β-1,4-glycosidic linkages of agar to generate neoagarotetraose (NA4) and neoagarohexaose (NA6) as the main products. These characteristics suggest that AgaML has potential application in cosmetic, pharmaceuticals and food industries.
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Romero-Rodríguez A, Rocha D, Ruiz-Villafan B, Tierrafría V, Rodríguez-Sanoja R, Segura-González D, Sánchez S. Transcriptomic analysis of a classical model of carbon catabolite regulation in Streptomyces coelicolor. BMC Microbiol 2016; 16:77. [PMID: 27121083 PMCID: PMC4848846 DOI: 10.1186/s12866-016-0690-y] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2015] [Accepted: 04/14/2016] [Indexed: 12/28/2022] Open
Abstract
BACKGROUND In the genus Streptomyces, one of the most remarkable control mechanisms of physiological processes is carbon catabolite repression (CCR). This mechanism regulates the expression of genes involved in the uptake and utilization of alternative carbon sources. CCR also affects the synthesis of secondary metabolites and morphological differentiation. Even when the outcome effect of CCR in different bacteria is the same, their essential mechanisms can be quite different. In several streptomycetes glucose kinase (Glk) represents the main glucose phosphorylating enzyme and has been regarded as a regulatory protein in CCR. To evaluate the paradigmatic model proposed for CCR in Streptomyces, a high-density microarray approach was applied to Streptomyces coelicolor M145, under repressed and non-repressed conditions. The transcriptomic study was extended to assess the ScGlk role in this model by comparing the transcriptomic profile of S. coelicolor M145 with that of a ∆glk mutant derived from the wild-type strain, complemented with a heterologous glk gene from Zymomonas mobilis (Zmglk), insensitive to CCR but able to grow in glucose (ScoZm strain). RESULTS Microarray experiments revealed that glucose influenced the expression of 651 genes. Interestingly, even when the ScGlk protein does not have DNA binding domains and the glycolytic flux was restored by a heterologous glucokinase, the ScGlk replacement modified the expression of 134 genes. From these, 91 were also affected by glucose while 43 appeared to be under the control of ScGlk. This work identified the expression of S. coelicolor genes involved in primary metabolism that were influenced by glucose and/or ScGlk. Aside from describing the metabolic pathways influenced by glucose and/or ScGlk, several unexplored transcriptional regulators involved in the CCR mechanism were disclosed. CONCLUSIONS The transcriptome of a classical model of CCR was studied in S. coelicolor to differentiate between the effects due to glucose or ScGlk in this regulatory mechanism. Glucose elicited important metabolic and transcriptional changes in this microorganism. While its entry and flow through glycolysis and pentose phosphate pathway were stimulated, the gluconeogenesis was inhibited. Glucose also triggered the CCR by repressing transporter systems and the transcription of enzymes required for secondary carbon sources utilization. Our results confirm and update the agar model of the CCR in Streptomyces and its dependence on the ScGlk per se. Surprisingly, the expected regulatory function of ScGlk was not found to be as global as thought before (only 43 out of 779 genes were affected), although may be accompanied or coordinated by other transcriptional regulators. Aside from describing the metabolic pathways influenced by glucose and/or ScGlk, several unexplored transcriptional regulators involved in the CCR mechanism were disclosed. These findings offer new opportunities to study and understand the CCR in S. coelicolor by increasing the number of known glucose and ScGlk -regulated pathways and a new set of putative regulatory proteins possibly involved or controlling the CCR.
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Affiliation(s)
- Alba Romero-Rodríguez
- Departamento de Biología Molecular y Biotecnología del Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Tercer Circuito Exterior s/n, Ciudad de Mexico, 04510, Mexico
| | - Diana Rocha
- Departamento de Biología Molecular y Biotecnología del Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Tercer Circuito Exterior s/n, Ciudad de Mexico, 04510, Mexico
| | - Beatriz Ruiz-Villafan
- Departamento de Biología Molecular y Biotecnología del Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Tercer Circuito Exterior s/n, Ciudad de Mexico, 04510, Mexico
| | - Víctor Tierrafría
- Departamento de Biología Molecular y Biotecnología del Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Tercer Circuito Exterior s/n, Ciudad de Mexico, 04510, Mexico
| | - Romina Rodríguez-Sanoja
- Departamento de Biología Molecular y Biotecnología del Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Tercer Circuito Exterior s/n, Ciudad de Mexico, 04510, Mexico
| | - Daniel Segura-González
- Departamento de Microbiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Ave. Universidad 2001, Cuernavaca, Mor. 62210, Mexico
| | - Sergio Sánchez
- Departamento de Biología Molecular y Biotecnología del Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Tercer Circuito Exterior s/n, Ciudad de Mexico, 04510, Mexico.
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Overexpression and secretion of AgaA7 from Pseudoalteromonas hodoensis sp. nov in Bacillus subtilis for the depolymerization of agarose. Enzyme Microb Technol 2016; 90:19-25. [PMID: 27241288 DOI: 10.1016/j.enzmictec.2016.04.009] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2015] [Revised: 02/18/2016] [Accepted: 04/19/2016] [Indexed: 12/20/2022]
Abstract
Interest in agar or agarose-based pharmaceutical products has driven the search for potent agarolytic enzymes. An extracellular β-agarase (AgaA7) recently isolated from Pseudoalteromonas hodoensis sp. nov was expressed in Bacillus subtilis, which was chosen due to its capability to overproduce and secrete functional enzymes. Phenotypic analysis showed that the engineered B. subtilis secreted a functional AgaA7 when fused with the aprE signal peptide (SP) at the amino-terminus. The maximum agarolytic activity was observed during the late logarithmic phase. To further improve the secretion of AgaA7, an expression library of AgaA7 fused to different naturally occurring B. subtilis SPs was created. The amount of AgaA7 secreted by the clones was compared through activity assay, immuno-blot, and purification via affinity chromatography. Although the aprE SP can readily facilitate the secretion of AgaA7, other SPs such as yqgA, pel, and lipA were relatively more efficient. Among these SPs, lipA was the most efficient in improving the secretion of AgaA7.The use of B. subtilis as host for the expression and secretion of agarolytic and other hydrolytic enzymes can be a useful tool in the field of white biotechnology.
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Park J, Hong SK, Chang YK. Production of DagA and ethanol by sequential utilization of sugars in a mixed-sugar medium simulating microalgal hydrolysate. BIORESOURCE TECHNOLOGY 2015; 191:414-419. [PMID: 25777065 DOI: 10.1016/j.biortech.2015.02.072] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2015] [Revised: 02/16/2015] [Accepted: 02/17/2015] [Indexed: 06/04/2023]
Abstract
A novel two-step fermentation process using a mixed-sugar medium mimicking microalgal hydrolysate has been proposed to avoid glucose repression and thus to maximize substrate utilization efficiency. When DagA, a β-agarase was produced in one step in the mixed-sugar medium by using a recombinant Streptomyces lividans, glucose was found to have negative effects on the consumption of the other sugars and DagA biosynthesis causing low substrate utilization efficiency and low DagA productivity. To overcome such difficulties, a new strategy of sequential substrate utilization was developed. In the first step, glucose was consumed by Saccharomyces cerevisiae together with galactose and mannose producing ethanol, after which DagA was produced from the remaining sugars of xylose, rhamnose and ribose. Fucose was not consumed. By adopting this two-step process, the overall substrate utilization efficiency was increased approximately 3-fold with a nearly 2-fold improvement of DagA production, let alone the additional benefit of ethanol production.
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Affiliation(s)
- Juyi Park
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology, 291, Daehak-ro, Yuseong-gu, Daejeon 305-701, Republic of Korea
| | - Soon-Kwang Hong
- Division of Bioscience and Bioinformatics, Myung-Ji University, San 38-2 Namdong, Yongin, Gyeonggido 449-728, Republic of Korea
| | - Yong Keun Chang
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology, 291, Daehak-ro, Yuseong-gu, Daejeon 305-701, Republic of Korea.
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Identification and biochemical characterization of a novel endo-type β-agarase AgaW from Cohnella sp. strain LGH. Appl Microbiol Biotechnol 2015; 99:10019-29. [PMID: 26245684 DOI: 10.1007/s00253-015-6869-6] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Revised: 06/30/2015] [Accepted: 07/16/2015] [Indexed: 11/27/2022]
Abstract
An agar-degrading bacterium, strain LGH, was isolated and identified as Cohnella sp. This strain had a capability of utilizing agar as a sole carbon source for growth and showed a strong agarolytic activity. A novel endo-type β-agarase gene agaW, encoding a primary translation product of 891 amino acids, including a 26 amino acid signal peptide, was cloned and identified from a genomic library of strain LGH. The AgaW belonged to the glycoside hydrolase (GH) GH50 family, with less than 39% amino acid sequence similarity with any known protein, and hydrolyzed agarose into neoagarotetraose as the major end product and neoagarobiose as the minor end product through other neoagarooligosaccharide intermediates, such as neoagarohexaose.
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Chi WJ, Lee CR, Dugerjonjuu S, Park JS, Kang DK, Hong SK. Biochemical characterization of a novel iron-dependent GH16 β-agarase, AgaH92, from an agarolytic bacterium Pseudoalteromonas sp. H9. FEMS Microbiol Lett 2015; 362:fnv035. [DOI: 10.1093/femsle/fnv035] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/01/2015] [Indexed: 01/26/2023] Open
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Park DY, Chi WJ, Park JS, Chang YK, Hong SK. Cloning, Expression, and Biochemical Characterization of a GH16 β-Agarase AgaH71 from Pseudoalteromonas hodoensis H7. Appl Biochem Biotechnol 2014; 175:733-47. [DOI: 10.1007/s12010-014-1294-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2014] [Accepted: 10/09/2014] [Indexed: 01/17/2023]
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Song T, Zhang W, Wei C, Jiang T, Xu H, Cao Y, Cao Y, Qiao D. Isolation and characterization of agar-degrading endophytic bacteria from plants. Curr Microbiol 2014; 70:275-81. [PMID: 25331792 DOI: 10.1007/s00284-014-0713-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2014] [Accepted: 09/02/2014] [Indexed: 10/24/2022]
Abstract
Agar is a polysaccharide extracted from the cell walls of some macro-algaes. Among the reported agarases, most of them come from marine environment. In order to better understand different sources of agarases, it is important to search new non-marine native ones. In this study, seven agar-degrading bacteria were first isolated from the tissues of plants, belonging to three genera, i.e., Paenibacillus sp., Pseudomonas sp., and Klebsiella sp. Among them, the genus Klebsiella was first reported to have agarolytic ability and the genus Pseudomonas was first isolated from non-marine environment with agarase activity. Besides, seven strains were characterized by investigating the growth and agarase production in the presence of various polysaccharides. The results showed that they could grow on several polysaccharides such as araban, carrageenan, chitin, starch, and xylan. Besides, they could also produce agarase in the presence of different polysaccharides other than agar. Extracellular agarases from seven strains were further analyzed by SDS-PAGE combined with activity staining and estimated to be 75 kDa which has great difference from most reported agarases.
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Affiliation(s)
- Tao Song
- Microbiology and Metabolic Engineering Key Laboratory of Sichuan Province, College of Life Sciences, Sichuan University, Wangjiang Road 29#, Chengdu, 610064, Sichuan, People's Republic of China
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A novel agarolytic β-galactosidase acts on agarooligosaccharides for complete hydrolysis of agarose into monomers. Appl Environ Microbiol 2014; 80:5965-73. [PMID: 25038102 DOI: 10.1128/aem.01577-14] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Marine red macroalgae have emerged to be renewable biomass for the production of chemicals and biofuels, because carbohydrates that form the major component of red macroalgae can be hydrolyzed into fermentable sugars. The main carbohydrate in red algae is agarose, and it is composed of D-galactose and 3,6-anhydro-L-galactose (AHG), which are alternately bonded by β1-4 and α1-3 linkages. In this study, a novel β-galactosidase that can act on agarooligosaccharides (AOSs) to release galactose was discovered in a marine bacterium (Vibrio sp. strain EJY3); the enzyme is annotated as Vibrio sp. EJY3 agarolytic β-galactosidase (VejABG). Unlike the lacZ-encoded β-galactosidase from Escherichia coli, VejABG does not hydrolyze common substrates like lactose and can act only on the galactose moiety at the nonreducing end of AOS. The optimum pH and temperature of VejABG on an agarotriose substrate were 7 and 35°C, respectively. Its catalytic efficiency with agarotriose was also similar to that with agaropentaose or agaroheptaose. Since agarotriose lingers as the unreacted residual oligomer in the currently available saccharification system using β-agarases and acid prehydrolysis, the agarotriose-hydrolyzing capability of this novel β-galactosidase offers an enormous advantage in the saccharification of agarose or agar in red macroalgae for its use as a biomass feedstock for fermentable sugar production.
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Production and Characterization of a Novel Thermostable Extracellular Agarase from Pseudoalteromonas hodoensis Newly Isolated from the West Sea of South Korea. Appl Biochem Biotechnol 2014; 173:1703-16. [DOI: 10.1007/s12010-014-0958-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2014] [Accepted: 05/12/2014] [Indexed: 10/25/2022]
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Song T, Cao Y, Xu H, Zhang W, Fei B, Qiao D, Cao Y. Purification and characterization of a novel β-agarase of Paenibacillus sp. SSG-1 isolated from soil. J Biosci Bioeng 2014; 118:125-9. [PMID: 24631192 DOI: 10.1016/j.jbiosc.2014.02.008] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2013] [Revised: 02/06/2014] [Accepted: 02/08/2014] [Indexed: 11/18/2022]
Abstract
Agar is a polysaccharide polymer material, generally extracted from seaweed. Most agar degradation strains were isolated from seawater. In order to find new species resources and novel agarase from soil, an agar-degrading bacterium Paenibacillus sp. SSG-1 was isolated from soil. Agarase SSG-1a was purified to homogeneity by 30.2 fold with a yield of 4.8% through ammonium sulfate precipitation, DEAE FF chromatography and native-PAGE separation. The tandem mass spectrometry (MS/MS) results indicated that purified SSG-1a should be a novel β-agarase. The molecular mass of SSG-1a was estimated to be 77 kDa. The optimal temperature and pH for SSG-1a were 50°C and pH 6.0, respectively. Moreover, SSG-1a was stable in pH range of 4.0-10.0 and at temperature up to 40°C. It could hydrolyze the β-1,4 linkage of agarose to produce neoagarohexaose (95 mol%) and neoagarooctaose (5 mol%). Metal ion Mn(2+) and reducing reagents (β-Me and DTT) could increase its activity by 150% and 60%, respectively.
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Affiliation(s)
- Tao Song
- Microbiology and Metabolic Engineering of Key Laboratory of Sichuan Province, College of Life Science, Sichuan University, Chengdu 610065, PR China
| | - Yu Cao
- Microbiology and Metabolic Engineering of Key Laboratory of Sichuan Province, College of Life Science, Sichuan University, Chengdu 610065, PR China
| | - Hui Xu
- Microbiology and Metabolic Engineering of Key Laboratory of Sichuan Province, College of Life Science, Sichuan University, Chengdu 610065, PR China
| | - Weijia Zhang
- Microbiology and Metabolic Engineering of Key Laboratory of Sichuan Province, College of Life Science, Sichuan University, Chengdu 610065, PR China
| | - Baojin Fei
- Microbiology and Metabolic Engineering of Key Laboratory of Sichuan Province, College of Life Science, Sichuan University, Chengdu 610065, PR China; Chengdu Ronsen Pharmaceuticals Co. Ltd., Chengdu 610061, PR China
| | - Dairong Qiao
- Microbiology and Metabolic Engineering of Key Laboratory of Sichuan Province, College of Life Science, Sichuan University, Chengdu 610065, PR China
| | - Yi Cao
- Microbiology and Metabolic Engineering of Key Laboratory of Sichuan Province, College of Life Science, Sichuan University, Chengdu 610065, PR China.
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Heterologous expression of a newly screened β-agarase from Alteromonas sp. GNUM1 in Escherichia coli and its application for agarose degradation. Process Biochem 2014. [DOI: 10.1016/j.procbio.2013.12.014] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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48
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Chi WJ, Park DY, Seo YB, Chang YK, Lee SY, Hong SK. Cloning, expression, and biochemical characterization of a novel GH16 β-agarase AgaG1 from Alteromonas sp. GNUM-1. Appl Microbiol Biotechnol 2014; 98:4545-55. [DOI: 10.1007/s00253-014-5510-4] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2013] [Revised: 12/24/2013] [Accepted: 12/28/2013] [Indexed: 11/25/2022]
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Pluvinage B, Hehemann JH, Boraston AB. Substrate recognition and hydrolysis by a family 50 exo-β-agarase, Aga50D, from the marine bacterium Saccharophagus degradans. J Biol Chem 2013; 288:28078-88. [PMID: 23921382 DOI: 10.1074/jbc.m113.491068] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
Abstract
The bacteria that metabolize agarose use multiple enzymes of complementary specificities to hydrolyze the glycosidic linkages in agarose, a linear polymer comprising the repeating disaccharide subunit of neoagarobiose (3,6-anhydro-l-galactose-α-(1,3)-d-galactose) that are β-(1,4)-linked. Here we present the crystal structure of a glycoside hydrolase family 50 exo-β-agarase, Aga50D, from the marine microbe Saccharophagus degradans. This enzyme catalyzes a critical step in the metabolism of agarose by S. degradans through cleaving agarose oligomers into neoagarobiose products that can be further processed into monomers. The crystal structure of Aga50D to 1.9 Å resolution reveals a (β/α)8-barrel fold that is elaborated with a β-sandwich domain and extensive loops. The structures of catalytically inactivated Aga50D in complex with non-hydrolyzed neoagarotetraose (2.05 Å resolution) and neoagarooctaose (2.30 Å resolution) provide views of Michaelis complexes for a β-agarase. In these structures, the d-galactose residue in the -1 subsite is distorted into a (1)S3 skew boat conformation. The relative positioning of the putative catalytic residues are most consistent with a retaining catalytic mechanism. Additionally, the neoagarooctaose complex showed that this extended substrate made substantial interactions with the β-sandwich domain, which resembles a carbohydrate-binding module, thus creating additional plus (+) subsites and funneling the polymeric substrate through the tunnel-shaped active site. A synthesis of these results in combination with an additional neoagarobiose product complex suggests a potential exo-processive mode of action of Aga50D on the agarose double helix.
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Affiliation(s)
- Benjamin Pluvinage
- From the Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia V8W 3P6, Canada and
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50
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Temuujin U, Chi WJ, Park JS, Chang YK, Song JY, Hong SK. Identification and characterization of a novel β-galactosidase from Victivallis vadensis ATCC BAA-548, an anaerobic fecal bacterium. J Microbiol 2012; 50:1034-40. [DOI: 10.1007/s12275-012-2478-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2012] [Accepted: 09/12/2012] [Indexed: 10/27/2022]
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