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Improved Stability and Hydrolysates of Hyperthermophilic GH57 Type II Pullulanase from the Deep-Sea Archaeon Thermococcus siculi HJ21 by Truncation. Catalysts 2023. [DOI: 10.3390/catal13030453] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2023] Open
Abstract
Pullulanase (EC 3.2.1.41) belongs to the amylase family and is often used alone or in combination with other amylases in the industrial production of starch-based products. This enzyme is often required in industrial production because of its better stability. We here truncated the pullulanase gene from the deep-sea hydrothermal anaerobic archaeon Thermococcus siculi HJ21 and obtained Pul-HJΔ782, which is a member of the α-amylase family GH57. The results revealed that the optimum temperature for Pul-HJΔ782 was 100 °C, and its thermostability at 100 °C improved after truncation. Less than 15% of its enzyme activity was lost after 1 h of incubation at 100 °C, and 57% activity remained after 5 h of treatment. Truncation significantly improved the overall pH tolerance range of Pul-HJΔ782, and its stability in the pH range 4–8 was over 80% relative activity from an average of 60%. The sequence and structural model of Pul-HJΔ782 was analyzed, and its instability index was reduced significantly. Furthermore, the hydrolysates of the truncated and wild-type pullulanase were analyzed, and the enzymatic digestion efficiency of the truncated Pul-HJΔ782 was higher.
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2
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Pcal_0976, a pullulanase homologue from Pyrobaculum calidifontis, displays a glycoside hydrolase activity but no pullulanase activity. Biologia (Bratisl) 2023. [DOI: 10.1007/s11756-022-01309-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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3
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Xie T, Zhou L, Han L, Cui W, Liu Z, Cheng Z, Guo J, Zhou Z. Modulating the pH profile of the pullulanase from Pyrococcus yayanosii CH1 by synergistically engineering the active center and surface. Int J Biol Macromol 2022; 216:132-139. [PMID: 35777517 DOI: 10.1016/j.ijbiomac.2022.06.151] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Revised: 06/14/2022] [Accepted: 06/23/2022] [Indexed: 11/24/2022]
Abstract
A preferable pullulanase with high thermostability and catalytic activity at pH 4.5-5 is desired to match with glucoamylase in the starch-saccharification process. However, most of them exhibit low activity under such low pH conditions. Here, the optimal pH of the hyperthermostable pullulanase from Pyrococcus yayanosii (PulPY2) was successfully shifted from 6.4 to 5 with a 2-fold increase in the specific activity based on synergistic engineering of the active center and surface. Synergistic engineering was performed by introducing histidine within 6 Å of the active sites, and by enhancing negative charges on the enzymatic surface. Two single-site mutants of PulPY2-Q13H and PulPY2-I25E with higher hydrolytic activity were obtained, the optimal pH of which was shifted to pH 5 and 5.4, respectively; the combined mutant PulPY2-Q13H/I25E exhibited the optimal pH of 5, 3.2-fold increasing catalytic efficiency at pH 5, and high thermostability compared to PulPY2. These results not only obtained an applicable pullulanase for industrial application, but also provided a strategy for shifting the optimal pH of the enzyme based on synergistic engineering of the active center and surface.
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Affiliation(s)
- Ting Xie
- The Key Laboratory of Industrial Biotechnology of Ministry of Education, School of Biotechnology, Jiangnan University, 1800 Lihu Avenue, Wuxi 214122, People's Republic of China
| | - Li Zhou
- The Key Laboratory of Industrial Biotechnology of Ministry of Education, School of Biotechnology, Jiangnan University, 1800 Lihu Avenue, Wuxi 214122, People's Republic of China
| | - Laichuang Han
- The Key Laboratory of Industrial Biotechnology of Ministry of Education, School of Biotechnology, Jiangnan University, 1800 Lihu Avenue, Wuxi 214122, People's Republic of China
| | - Wenjing Cui
- The Key Laboratory of Industrial Biotechnology of Ministry of Education, School of Biotechnology, Jiangnan University, 1800 Lihu Avenue, Wuxi 214122, People's Republic of China
| | - Zhongmei Liu
- The Key Laboratory of Industrial Biotechnology of Ministry of Education, School of Biotechnology, Jiangnan University, 1800 Lihu Avenue, Wuxi 214122, People's Republic of China
| | - Zhongyi Cheng
- The Key Laboratory of Industrial Biotechnology of Ministry of Education, School of Biotechnology, Jiangnan University, 1800 Lihu Avenue, Wuxi 214122, People's Republic of China
| | - Junling Guo
- The Key Laboratory of Industrial Biotechnology of Ministry of Education, School of Biotechnology, Jiangnan University, 1800 Lihu Avenue, Wuxi 214122, People's Republic of China
| | - Zhemin Zhou
- The Key Laboratory of Industrial Biotechnology of Ministry of Education, School of Biotechnology, Jiangnan University, 1800 Lihu Avenue, Wuxi 214122, People's Republic of China.
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Microbial starch debranching enzymes: Developments and applications. Biotechnol Adv 2021; 50:107786. [PMID: 34147588 DOI: 10.1016/j.biotechadv.2021.107786] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Revised: 06/04/2021] [Accepted: 06/15/2021] [Indexed: 12/28/2022]
Abstract
Starch debranching enzymes (SDBEs) hydrolyze the α-1,6 glycosidic bonds in polysaccharides such as starch, amylopectin, pullulan and glycogen. SDBEs are also important enzymes for the preparation of sugar syrup, resistant starch and cyclodextrin. As the synergistic catalysis of SDBEs and other starch-acting hydrolases can effectively improve the raw material utilization and production efficiency during starch processing steps such as saccharification and modification, they have attracted substantial research interest in the past decades. The substrate specificities of the two major members of SDBEs, pullulanases and isoamylases, are quite different. Pullulanases generally require at least two α-1,4 linked glucose units existing on both sugar chains linked by the α-1,6 bond, while isoamylases require at least three units of α-1,4 linked glucose. SDBEs mainly belong to glycoside hydrolase (GH) family 13 and 57. Except for GH57 type II pullulanse, GH13 pullulanases and isoamylases share plenty of similarities in sequence and structure of the core catalytic domains. However, the N-terminal domains, which might be one of the determinants contributing to the substrate binding of SDBEs, are distinct in different enzymes. In order to overcome the current defects of SDBEs in catalytic efficiency, thermostability and expression level, great efforts have been made to develop effective enzyme engineering and fermentation strategies. Herein, the diverse biochemical properties and distinct features in the sequence and structure of pullulanase and isoamylase from different sources are summarized. Up-to-date developments in the enzyme engineering, heterologous production and industrial applications of SDBEs is also reviewed. Finally, research perspective which could help understanding and broadening the applications of SDBEs are provided.
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5
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Sequence analysis and biochemical properties of an acidophilic and hyperthermophilic amylopullulanase from Thermofilum pendens. Int J Biol Macromol 2018; 114:235-243. [DOI: 10.1016/j.ijbiomac.2018.03.073] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2018] [Revised: 03/12/2018] [Accepted: 03/15/2018] [Indexed: 11/18/2022]
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6
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Kumar S, Arumugam N, Permaul K, Singh S. Chapter 5 Thermostable Enzymes and Their Industrial Applications. Microb Biotechnol 2016. [DOI: 10.1201/9781315367880-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/12/2023] Open
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7
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Møller MS, Henriksen A, Svensson B. Structure and function of α-glucan debranching enzymes. Cell Mol Life Sci 2016; 73:2619-41. [PMID: 27137180 PMCID: PMC11108273 DOI: 10.1007/s00018-016-2241-y] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2016] [Accepted: 04/22/2016] [Indexed: 10/21/2022]
Abstract
α-Glucan debranching enzymes hydrolyse α-1,6-linkages in starch/glycogen, thereby, playing a central role in energy metabolism in all living organisms. They belong to glycoside hydrolase families GH13 and GH57 and several of these enzymes are industrially important. Nine GH13 subfamilies include α-glucan debranching enzymes; isoamylase and glycogen debranching enzymes (GH13_11); pullulanase type I/limit dextrinase (GH13_12-14); pullulan hydrolase (GH13_20); bifunctional glycogen debranching enzyme (GH13_25); oligo-1 and glucan-1,6-α-glucosidases (GH13_31); pullulanase type II (GH13_39); and α-amylase domains (GH13_41) in two-domain amylase-pullulanases. GH57 harbours type II pullulanases. Specificity differences, domain organisation, carbohydrate binding modules, sequence motifs, three-dimensional structures and specificity determinants are discussed. The phylogenetic analysis indicated that GH13_39 enzymes could represent a "missing link" between the strictly α-1,6-specific debranching enzymes and the enzymes with dual specificity and α-1,4-linkage preference.
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Affiliation(s)
- Marie Sofie Møller
- Enzyme and Protein Chemistry, Department of Systems Biology, Technical University of Denmark, 2800, Kongens Lyngby, Denmark.
- Center for Molecular Protein Science, Department of Chemistry, Lund University, 221 00, Lund, Sweden.
| | - Anette Henriksen
- Global Research Unit, Department of Large Protein Biophysics and Formulation, Novo Nordisk A/S, Novo Nordisk Park, 2760, Måløv, Denmark
| | - Birte Svensson
- Enzyme and Protein Chemistry, Department of Systems Biology, Technical University of Denmark, 2800, Kongens Lyngby, Denmark
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8
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Nisha M, Satyanarayana T. Characteristics, protein engineering and applications of microbial thermostable pullulanases and pullulan hydrolases. Appl Microbiol Biotechnol 2016; 100:5661-79. [DOI: 10.1007/s00253-016-7572-y] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Revised: 04/15/2016] [Accepted: 04/19/2016] [Indexed: 12/17/2022]
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9
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Ahmad N, Mehboob S, Rashid N. Starch-processing enzymes — emphasis on thermostable 4-α-glucanotransferases. Biologia (Bratisl) 2015. [DOI: 10.1515/biolog-2015-0087] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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10
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Soo E, Rudrappa D, Blum P. Membrane Association and Catabolite Repression of the Sulfolobus solfataricus α-Amylase. Microorganisms 2015; 3:567-87. [PMID: 27682106 PMCID: PMC5023256 DOI: 10.3390/microorganisms3030567] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2015] [Revised: 08/10/2015] [Accepted: 09/11/2015] [Indexed: 11/16/2022] Open
Abstract
Sulfolobus solfataricus is a thermoacidophilic member of the archaea whose envelope consists of an ether-linked lipid monolayer surrounded by a protein S-layer. Protein translocation across this envelope must accommodate a steep proton gradient that is subject to temperature extremes. To better understand this process in vivo, studies were conducted on the S. solfataricus glycosyl hydrolyase family 57 α-Amylase (AmyA). Cell lines harboring site specific modifications of the amyA promoter and AmyA structural domains were created by gene replacement using markerless exchange and characterized by Western blot, enzyme assay and culture-based analysis. Fusion of amyA to the malAp promoter overcame amyAp-mediated regulatory responses to media composition including glucose and amino acid repression implicating action act at the level of transcription. Deletion of the AmyA Class II N-terminal signal peptide blocked protein secretion and intracellular protein accumulation. Deletion analysis of a conserved bipartite C-terminal motif consisting of a hydrophobic region followed by several charged residues indicated the charged residues played an essential role in membrane-association but not protein secretion. Mutants lacking the C-terminal bipartite motif exhibited reduced growth rates on starch as the sole carbon and energy source; therefore, association of AmyA with the membrane improves carbohydrate utilization. Widespread occurrence of this motif in other secreted proteins of S. solfataricus and of related Crenarchaeota suggests protein association with membranes is a general trait used by these organisms to influence external processes.
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Affiliation(s)
- Edith Soo
- School of Biological Sciences, University of Nebraska-Lincoln, 1901 Vine Street, Lincoln 68588, NE, USA.
| | - Deepak Rudrappa
- School of Biological Sciences, University of Nebraska-Lincoln, 1901 Vine Street, Lincoln 68588, NE, USA.
| | - Paul Blum
- School of Biological Sciences, University of Nebraska-Lincoln, 1901 Vine Street, Lincoln 68588, NE, USA.
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11
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Farrán A, Cai C, Sandoval M, Xu Y, Liu J, Hernáiz MJ, Linhardt RJ. Green solvents in carbohydrate chemistry: from raw materials to fine chemicals. Chem Rev 2015; 115:6811-53. [PMID: 26121409 DOI: 10.1021/cr500719h] [Citation(s) in RCA: 155] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Angeles Farrán
- †Departamento de Química Orgánica y Bio-Orgánica, Facultad de Ciencias, Universidad Nacional de Educación a Distancia, Paseo Senda del Rey 4, 28040 Madrid, Spain
| | - Chao Cai
- ‡Key Laboratory of Marine Drugs of Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, China
| | - Manuel Sandoval
- §Escuela de Química, Universidad Nacional of Costa Rica, Post Office Box 86, 3000 Heredia, Costa Rica
| | - Yongmei Xu
- ∥Division of Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, North Carolina 27599, United States
| | - Jian Liu
- ∥Division of Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, North Carolina 27599, United States
| | - María J Hernáiz
- ▽Departamento de Química Orgánica y Farmacéutica, Facultad de Farmacia, Universidad Complutense de Madrid, Pz/Ramón y Cajal s/n, 28040 Madrid, Spain
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A GH57 4-α-glucanotransferase of hyperthermophilic origin with potential for alkyl glycoside production. Appl Microbiol Biotechnol 2015; 99:7101-13. [DOI: 10.1007/s00253-015-6435-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2014] [Revised: 01/23/2015] [Accepted: 01/24/2015] [Indexed: 10/24/2022]
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13
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Guan Q, Guo X, Han T, Wei M, Jin M, Zeng F, Liu L, Li Z, Wang Y, Cheong GW, Zhang S, Jia B. Cloning, purification and biochemical characterisation of an organic solvent-, detergent-, and thermo-stable amylopullulanase from Thermococcus kodakarensis KOD1. Process Biochem 2013. [DOI: 10.1016/j.procbio.2013.04.007] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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14
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Janeček S, Kuchtová A. In silico identification of catalytic residues and domain fold of the family GH119 sharing the catalytic machinery with the α-amylase family GH57. FEBS Lett 2012; 586:3360-6. [PMID: 22819817 DOI: 10.1016/j.febslet.2012.07.020] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2012] [Revised: 06/30/2012] [Accepted: 07/04/2012] [Indexed: 10/28/2022]
Abstract
The glycoside hydrolase family 119 (GH119) contains the α-amylase from Bacillus circulans and five other hypothetical proteins. Until now, nothing has been reported on the catalytic residues and catalytic-domain fold of GH119. Based on a detailed in silico analysis involving sequence comparison in combination with BLAST searches and structural modelling, an unambiguous relationship was revealed between the families GH119 and GH57. This includes sharing the catalytic residues, i.e. Glu231 and Asp373 as catalytic nucleophile and proton donor, respectively, in the predicted catalytic (β/α)(7)-barrel domain of GH119 B. circulans α-amylase. The GH57 and GH119 families may thus define a new CAZy clan.
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Affiliation(s)
- Stefan Janeček
- Laboratory of Protein Evolution, Institute of Molecular Biology, Slovak Academy of Sciences, Bratislava, Slovakia.
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15
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Jiao YL, Wang SJ, Lv MS, Fang YW, Liu S. An evolutionary analysis of the GH57 amylopullulanases based on the DOMON_glucodextranase_like domains. J Basic Microbiol 2012; 53:231-9. [DOI: 10.1002/jobm.201100530] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2011] [Accepted: 01/18/2012] [Indexed: 11/11/2022]
Affiliation(s)
- Yu-Liang Jiao
- College of Marine Sciences; HuaiHai Institute of Technology; Lianyungang, People's Republic of China
| | - Shu-Jun Wang
- College of Marine Sciences; HuaiHai Institute of Technology; Lianyungang, People's Republic of China
| | - Ming-Sheng Lv
- College of Marine Sciences; HuaiHai Institute of Technology; Lianyungang, People's Republic of China
| | - Yao-Wei Fang
- College of Marine Sciences; HuaiHai Institute of Technology; Lianyungang, People's Republic of China
| | - Shu Liu
- College of Marine Sciences; HuaiHai Institute of Technology; Lianyungang, People's Republic of China
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Sequence fingerprints of enzyme specificities from the glycoside hydrolase family GH57. Extremophiles 2012; 16:497-506. [PMID: 22527043 DOI: 10.1007/s00792-012-0449-9] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2012] [Accepted: 04/02/2012] [Indexed: 10/28/2022]
Abstract
The glycoside hydrolase family 57 (GH57) contains five well-established enzyme specificities: α-amylase, amylopullulanase, branching enzyme, 4-α-glucanotransferase and α-galactosidase. Around 700 GH57 members originate from Bacteria and Archaea, a substantial number being produced by thermophiles. An intriguing feature of family GH57 is that only slightly more than 2 % of its members (i.e., less than 20 enzymes) have already been biochemically characterized. The main goal of the present bioinformatics study was to retrieve from databases, and analyze in detail, sequences having clear features of the five GH57 enzyme specificities mentioned above. Of the 367 GH57 sequences, 56 were evaluated as α-amylases, 99 as amylopullulanases, 158 as branching enzymes, 46 as 4-α-glucanotransferases and 8 as α-galactosidases. Based on the analysis of collected sequences, sequence logos were created for each specificity and unique sequence features were identified within the logos. These features were proposed to define the so-called sequence fingerprints of GH57 enzyme specificities. Domain arrangements characteristic of the individual enzyme specificities as well as evolutionary relationships within the family GH57 are also discussed. The results of this study could find use in rational protein design of family GH57 amylolytic enzymes and also in the possibility of assigning a GH57 specificity to a hypothetical GH57 member prior to its biochemical characterization.
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17
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Janeček Š, Blesák K. Sequence-Structural Features and Evolutionary Relationships of Family GH57 α-Amylases and Their Putative α-Amylase-Like Homologues. Protein J 2011; 30:429-35. [DOI: 10.1007/s10930-011-9348-7] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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18
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Jiao YL, Wang SJ, Lv MS, Xu JL, Fang YW, Liu S. A GH57 family amylopullulanase from deep-sea Thermococcus siculi: expression of the gene and characterization of the recombinant enzyme. Curr Microbiol 2010; 62:222-8. [PMID: 20593184 DOI: 10.1007/s00284-010-9690-6] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2010] [Accepted: 05/28/2010] [Indexed: 11/30/2022]
Abstract
The gene encoding a new extracellular amylopullulanase (type II pullulanase) was cloned from an extremely thermophilic anaerobic archaeon Thermococcus siculi strain HJ21 isolated previously from a deep-sea hydrothermal vent. The functional hydrolytic domain of the amylopullulanase (TsiApuN) and its MalE fusion protein (MTsiApuN) were expressed heterologously. The complete amylopullulanase (TsiApu) was also purified from fermentation broth of the strain. The pullulanase and amylase activities of the three enzymes were characterized. TsiApu had optimum temperature of 95°C for the both activities, while MTsiApuN and TsiApuN had a higher optimum temperature of 100°C. The residual total activities of MTsiApuN and TsiApuN were both 89% after incubation at 100°C for 1 h, while that of TsiApu was 70%. For all the three enzymes the optimum pHs for amylase and pullulanase activities were 5.0 and 6.0, respectively. By analyzing enzymatic properties of the three enzymes, this study suggests that the carboxy terminal region of TsiApu might interfere with the thermoactivity. The acidic thermoactive amylopullulanases MTsiApuN and TsiApuN could be further employed for industrial saccharification of starch.
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Affiliation(s)
- Yu-Liang Jiao
- College of Marine Sciences, HuaiHai Institute of Technology, Lianyungang, 222005, People's Republic of China.
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Characterization of ApuB, an extracellular type II amylopullulanase from Bifidobacterium breve UCC2003. Appl Environ Microbiol 2008; 74:6271-9. [PMID: 18689518 DOI: 10.1128/aem.01169-08] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
The apuB gene of Bifidobacterium breve UCC2003 was shown to encode an extracellular amylopullulanase. ApuB is composed of a distinct N-terminally located alpha-amylase-containing domain which hydrolyzes alpha-1,4-glucosidic linkages in starch and related polysaccharides and a C-terminally located pullulanase-containing domain which hydrolyzes alpha-1,6 linkages in pullulan, allowing the classification of this enzyme as a bifunctional class II pullulanase. A knockout mutation of the apuB gene in B. breve UCC2003 rendered the resulting mutant incapable of growth in medium containing starch, amylopectin, glycogen, or pullulan as the sole carbon and energy source, confirming the crucial physiological role of this gene in starch metabolism.
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Ballschmiter M, Fütterer O, Liebl W. Identification and characterization of a novel intracellular alkaline alpha-amylase from the hyperthermophilic bacterium Thermotoga maritima MSB8. Appl Environ Microbiol 2006; 72:2206-11. [PMID: 16517673 PMCID: PMC1393205 DOI: 10.1128/aem.72.3.2206-2211.2006] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The gene for a novel alpha-amylase, designated AmyC, from the hyperthermophilic bacterium Thermotoga maritima was cloned and heterologously overexpressed in Escherichia coli. The putative intracellular enzyme had no amino acid sequence similarity to glycoside hydrolase family (GHF) 13 alpha-amylases, yet the range of substrate hydrolysis and the product profile clearly define the protein as an alpha-amylase. Based on sequence similarity AmyC belongs to a subgroup within GHF 57. On the basis of amino acid sequence similarity, Glu185 and Asp349 could be identified as the catalytic residues of AmyC. Using a 60-min assay, the maximum hydrolytic activity of the purified enzyme, which was dithiothreitol dependent, was found to be at 90 degrees C. AmyC displayed a remarkably high pH optimum of pH 8.5 and an unusual sensitivity towards both ATP and EDTA.
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Affiliation(s)
- Meike Ballschmiter
- Institut für Mikrobiologie und Genetik, Georg-August-Universität Göttingen, Grisebachstr. 8, D-37077 Göttingen, Germany
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Antranikian G, Vorgias CE, Bertoldo C. Extreme environments as a resource for microorganisms and novel biocatalysts. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2005; 96:219-62. [PMID: 16566093 DOI: 10.1007/b135786] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
Abstract
The steady increase in the number of newly isolated extremophilic microorganisms and the discovery of their enzymes by academic and industrial institutions underlines the enormous potential of extremophiles for application in future biotechnological processes. Enzymes from extremophilic microorganisms offer versatile tools for sustainable developments in a variety of industrial application as they show important environmental benefits due to their biodegradability, specific stability under extreme conditions, improved use of raw materials and decreased amount of waste products. Although major advances have been made in the last decade, our knowledge of the physiology, metabolism, enzymology and genetics of this fascinating group of extremophilic microorganisms and their related enzymes is still limited. In-depth information on the molecular properties of the enzymes and their genes, however, has to be obtained to analyze the structure and function of proteins that are catalytically active around the boiling and freezing points of water and extremes of pH. New techniques, such as genomics, metanogenomics, DNA evolution and gene shuffling, will lead to the production of enzymes that are highly specific for countless industrial applications. Due to the unusual properties of enzymes from extremophiles, they are expected to optimize already existing processes or even develop new sustainable technologies.
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Affiliation(s)
- Garabed Antranikian
- Institute of Technical Microbiology, Technical University Hamburg-Harburg, Kasernenstrasse 12, 21073 Hamburg, Germany.
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