1
|
Jung JH, Hong S, Jeon EJ, Kim MK, Seo DH, Woo EJ, Holden JF, Park CS. Acceptor dependent catalytic properties of GH57 4-α-glucanotransferase from Pyrococcus sp. ST04. Front Microbiol 2022; 13:1016675. [PMID: 36274706 PMCID: PMC9582752 DOI: 10.3389/fmicb.2022.1016675] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Accepted: 09/20/2022] [Indexed: 11/13/2022] Open
Abstract
The 4-α-glucanotransferase (4-α-GTase or amylomaltase) is an essential enzyme in maltodextrin metabolism. Generally, most bacterial 4-α-GTase is classified into glycoside hydrolase (GH) family 77. However, hyperthermophiles have unique 4-α-GTases belonging to GH family 57. These enzymes are the main amylolytic protein in hyperthermophiles, but their mode of action in maltooligosaccharide utilization is poorly understood. In the present study, we investigated the catalytic properties of 4-α-GTase from the hyperthermophile Pyrococcus sp. ST04 (PSGT) in the presence of maltooligosaccharides of various lengths. Unlike 4-α-GTases in GH family 77, GH family 57 PSGT produced maltotriose in the early stage of reaction and preferred maltose and maltotriose over glucose as the acceptor. The kinetic analysis showed that maltotriose had the lowest KM value, which increased amylose degradation activity by 18.3-fold. Structural models of PSGT based on molecular dynamic simulation revealed two aromatic amino acids interacting with the substrate at the +2 and +3 binding sites, and the mutational study demonstrated they play a critical role in maltotriose binding. These results clarify the mode of action in carbohydrate utilization and explain acceptor binding mechanism of GH57 family 4-α-GTases in hyperthermophilic archaea.
Collapse
Affiliation(s)
- Jong-Hyun Jung
- Radiation Research Division, Korea Atomic Energy Research Institute, Jeongeup, South Korea
| | - Seungpyo Hong
- Department of Molecular Biology, Jeonbuk National University, Jeonju, South Korea
| | - Eun Jung Jeon
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, South Korea
| | - Min-Kyu Kim
- Radiation Research Division, Korea Atomic Energy Research Institute, Jeongeup, South Korea
| | - Dong-Ho Seo
- Department of Food Science and Technology, Jeonbuk National University, Jeonju, South Korea
| | - Eui-Jeon Woo
- Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, South Korea
| | - James F. Holden
- Department of Microbiology, University of Messachusetts, Amherst, MA, United States
| | - Cheon-Seok Park
- Department of Food Science and Biotechnology and Institute of Life Science and Resources, Kyung Hee University, Yongin, South Korea
- *Correspondence: Cheon-Seok Park,
| |
Collapse
|
2
|
Jiang Y, Li X, Pijning T, Bai Y, Dijkhuizen L. Mutations in Amino Acid Residues of Limosilactobacillus reuteri 121 GtfB 4,6-α-Glucanotransferase that Affect Reaction and Product Specificity. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2022; 70:1952-1961. [PMID: 35129339 DOI: 10.1021/acs.jafc.1c07618] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Limosilactobacillus reuteri 121 4,6-α-glucanotransferase (Lr121 4,6-α-GTase), belonging to the glycosyl hydrolase (GH) 70 GtfB subfamily, converts starch and maltodextrins into linear isomalto/malto polysaccharides (IMMPs) with consecutive (α1 → 6) linkages. The recent elucidation of its crystal structure allowed identification and analysis of further structural features that determine its reaction and product specificity. Herein, sequence alignments between GtfB enzymes with different product linkage specificities (4,6-α-GTase and 4,3-α-GTase) identified amino acid residues in GH70 homology motifs, which may be critical for reaction and product specificity. Based on these alignments, four Lr121 GtfB-ΔN mutants (I1020M, S1057P, H1056G, and Q1126I) were constructed. Compared to wild-type Lr121 GtfB-ΔN, mutants S1057P and Q1126I had considerably improved catalytic efficiencies. Mutants H1056G and Q1126I showed a 9% decrease and an 11% increase, respectively, in the ratio of (α1 → 6) over (α1 → 4) linkages in maltodextrin-derived products. A change in linkage type (e.g., (α1 → 6) linkages to (α1 → 3) linkages) was not observed. The possible functional roles of these Lr121 GtfB-ΔN residues located around the acceptor substrate-binding subsites are discussed. The results provide new insights into structural determinants of the reaction and product specificity of Lr121 GtfB 4,6-α-GTase.
Collapse
Affiliation(s)
- Yawen Jiang
- State Key laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, Jiangsu Province, China
- School of Food Science and Technology, Jiangnan University, Wuxi 214122, Jiangsu Province, China
- Synergetic Innovation Center of Food Safety and Nutrition, Jiangnan University, Wuxi 214122, Jiangsu Province, China
- International Joint Laboratory on Food Safety, Jiangnan University, Wuxi 214122, Jiangsu Province, China
| | - Xiaoxiao Li
- State Key laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, Jiangsu Province, China
- School of Food Science and Technology, Jiangnan University, Wuxi 214122, Jiangsu Province, China
- Synergetic Innovation Center of Food Safety and Nutrition, Jiangnan University, Wuxi 214122, Jiangsu Province, China
- International Joint Laboratory on Food Safety, Jiangnan University, Wuxi 214122, Jiangsu Province, China
| | - Tjaard Pijning
- Biomolecular X-ray Crystallography, Groningen Biomolecular Sciences and Biotechnology Institute (GBB), University of Groningen, 9747 AG Groningen, The Netherlands
| | - Yuxiang Bai
- State Key laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, Jiangsu Province, China
- School of Food Science and Technology, Jiangnan University, Wuxi 214122, Jiangsu Province, China
- Synergetic Innovation Center of Food Safety and Nutrition, Jiangnan University, Wuxi 214122, Jiangsu Province, China
- International Joint Laboratory on Food Safety, Jiangnan University, Wuxi 214122, Jiangsu Province, China
| | - Lubbert Dijkhuizen
- Microbial Physiology, Groningen Biomolecular Sciences and Biotechnology Institute (GBB), University of Groningen, 9747 AG Groningen, The Netherlands
- CarbExplore Research B.V., 9747 AA Groningen, The Netherlands
| |
Collapse
|
3
|
Park J, Rho SJ, Kim YR. Feasibility and characterization of the cycloamylose production from high amylose corn starch. Cereal Chem 2018. [DOI: 10.1002/cche.10102] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Jiwoon Park
- Department of Biosystems & Biomaterials Science and Engineering; Seoul National University; Seoul Korea
| | - Shin-Joung Rho
- Center for Food and Bioconvergence; Seoul National University; Seoul Korea
| | - Yong-Ro Kim
- Department of Biosystems & Biomaterials Science and Engineering; Seoul National University; Seoul Korea
- Center for Food and Bioconvergence; Seoul National University; Seoul Korea
| |
Collapse
|
4
|
Tumhom S, Krusong K, Kidokoro SI, Katoh E, Pongsawasdi P. Significance of H461 at subsite +1 in substrate binding and transglucosylation activity of amylomaltase from Corynebacterium glutamicum. Arch Biochem Biophys 2018; 652:3-8. [PMID: 29885290 DOI: 10.1016/j.abb.2018.06.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Revised: 05/28/2018] [Accepted: 06/05/2018] [Indexed: 10/14/2022]
Abstract
Amylomaltase (AM) catalyzes inter- and intra-molecular transglycosylation reactions of glucan to yield linear and cyclic oligosaccharide products. The functional roles of the conserved histidine at position 461 in the active site of AM from Corynebacterium glutamicum (CgAM) was investigated. H461 A/S/D/R/W were constructed, their catalytic properties were compared to the wild-type (WT). A significant decrease in transglucosylation activities was observed, especially in H461A mutant, while hydrolysis activity was barely affected. The transglucosylation factor of the H461A-CgAM was decreased by 8.6 folds. WT preferred maltotriose (G3) as substrate for disproportionation reaction, but all H461 mutants showed higher preference for maltose (G2). Using G3 substrate, kcat/Km values of H461 mutated CgAMs were 40-64 folds lower, while the Km values were twice higher than those of WT. All mutants could not produce large-ring cyclodextrin (LR-CD) product. The heat capacity profile indicated that WT had higher thermal stability than H461A. The X-ray structure of WT showed two H-bonds between H461 and heptasaccharide analog at subsite +1, while no such bonding was observed from the model structure of H461A. The importance of H461 on substrate binding with CgAM was evidenced. We are the first to mutate an active site histidine in AM to explore its function.
Collapse
Affiliation(s)
- Suthipapun Tumhom
- Starch and Cyclodextrin Research Unit, Department of Biochemistry, Faculty of Science, Chulalongkorn University, Bangkok, 10330, Thailand
| | - Kuakarun Krusong
- Starch and Cyclodextrin Research Unit, Department of Biochemistry, Faculty of Science, Chulalongkorn University, Bangkok, 10330, Thailand; Structural and Computational Biology Research Group, Department of Biochemistry, Faculty of Science, Chulalongkorn University, Bangkok, 10330, Thailand
| | - Shun-Ichi Kidokoro
- Department of Bioengineering, Nagaoka University of Technology, Nagaoka, Niigata, 940-2188, Japan
| | - Etsuko Katoh
- Structural Biology Research Unit, Advanced Analysis Center, National Agriculture and Food Research Organization, 3-1-3 Kannondai, Tsukuba, 305-8617, Ibaraki, Japan
| | - Piamsook Pongsawasdi
- Starch and Cyclodextrin Research Unit, Department of Biochemistry, Faculty of Science, Chulalongkorn University, Bangkok, 10330, Thailand.
| |
Collapse
|
5
|
Washio T, Oikawa T. Thermostable and highly specific L-aspartate oxidase from Thermococcus litoralis DSM 5473: cloning, overexpression, and enzymological properties. Extremophiles 2017; 22:59-71. [PMID: 29143132 DOI: 10.1007/s00792-017-0977-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Accepted: 11/03/2017] [Indexed: 11/30/2022]
Abstract
We successfully expressed the L-aspartate oxidase homolog gene (accession no: OCC_06611) of Thermococcus litoralis DSM 5473 in the soluble fraction of Escherichia coli BL21 (DE3) using a pET21b vector with 6X His tag at its C-terminus. The gene product (Tl-LASPO) showed L-aspartate oxidase activity in the presence of FAD in vitro, and this report is the first that details an L-aspartate oxidase derived from a Thermococcus species. The homologs of Tl-LASPO existed mainly in archaea, especially in the genus of Thermococcus, Pyrococcus, Sulfolobus, and Halobacteria. The quaternary structure of Tl-LASPO was homotrimeric with a subunit molecular mass of 52 kDa. The enzyme activity of Tl-LASPO increased with temperature up to 70 °C. Tl-LASPO was active from pH 6.0 to 9.0, and its highest activity was at pH 8.0. Tl-LASPO was stable at 80 °C for 1 h. The highest k cat/K m value was observed in assays at 70 °C. Tl-LASPO was highly specific for L-aspartic acid. Tl-LASPO utilized fumaric acid, 2,6-dichlorophenolindophenol, and ferricyanide in addition to FAD as a cofactor under anaerobic conditions. The absorption spectrum of holo-Tl-LASPO exhibited maxima at 380 and 450 nm. The FAD dissociation constant, K d, of the FAD-Tl-LASPO complex was determined to be 5.9 × 10-9 M.
Collapse
Affiliation(s)
- Tsubasa Washio
- Department of Life Science and Biotechnology, Faculty of Chemistry, Materials and Bioengineering, Kansai University, 3-3-35 Yamate-Cho, Suita, Osaka, 564-8680, Japan
| | - Tadao Oikawa
- Department of Life Science and Biotechnology, Faculty of Chemistry, Materials and Bioengineering, Kansai University, 3-3-35 Yamate-Cho, Suita, Osaka, 564-8680, Japan. .,Kansai University High Technology Research Center, 3-3-35 Yamate-Cho, Suita, Osaka, 564-8680, Japan.
| |
Collapse
|
6
|
Structural basis for the roles of starch and sucrose in homo-exopolysaccharide formation by Lactobacillus reuteri 35-5. Carbohydr Polym 2016; 151:29-39. [DOI: 10.1016/j.carbpol.2016.05.048] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2016] [Revised: 05/12/2016] [Accepted: 05/15/2016] [Indexed: 12/22/2022]
|
7
|
Mehboob S, Ahmad N, Rashid N, Imanaka T, Akhtar M. Pcal_0768, a hyperactive 4-α-glucanotransferase from Pyrobacculum calidifontis. Extremophiles 2016; 20:559-66. [PMID: 27295220 DOI: 10.1007/s00792-016-0850-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2016] [Accepted: 05/31/2016] [Indexed: 12/01/2022]
Abstract
Genome sequence of hyperthermophilic archaeon Pyrobaculum calidifontis revealed the presence of an open reading frame, Pcal_0768, corresponding to a putative 4-α-glucanotranferase belonging to glycoside hydrolases (GH) family 77. We have produced, in Escherichia coli, and purified recombinant Pcal_0768 which exhibited high disproportionation (690 U mg(-1)) activity. To the best of our knowledge, this is the highest ever reported activity for any member of family GH77. Maltooligosaccharides, when used as sole substrates, were disproportionated into linear maltooligohomologues. The analysis of the reaction end products revealed no evidence for the production of cycloamyloses. Catalytic activity of the enzyme remained unchanged in the presence or the absence of ionic and nonionic detergents. γ-cyclodextrin, an inhibitor of 4-α-glucanotransferases, did not show any inhibitory effect on Pcal_0768 activity. These properties make Pcal_0768 a potential candidate for starch processing industry.
Collapse
Affiliation(s)
- Sumaira Mehboob
- School of Biological Sciences, University of the Punjab, Quaid-e-Azam Campus, Lahore, 54590, Pakistan
| | - Nasir Ahmad
- Institute of Agricultural Sciences, University of the Punjab, Quaid-e-Azam Campus, Lahore, 54590, Pakistan
| | - Naeem Rashid
- School of Biological Sciences, University of the Punjab, Quaid-e-Azam Campus, Lahore, 54590, Pakistan.
| | - Tadayuki Imanaka
- The Research Organization of Science and Technology, Ritsumeikan University, Kusatsu, Shiga, 525-8577, Japan
| | - Muhammad Akhtar
- School of Biological Sciences, University of the Punjab, Quaid-e-Azam Campus, Lahore, 54590, Pakistan.,School of Biological Sciences, University of Southampton, Southampton, SO16 7PX, UK
| |
Collapse
|
8
|
Zhou W, You C, Ma H, Ma Y, Zhang YHP. One-Pot Biosynthesis of High-Concentration α-Glucose 1-Phosphate from Starch by Sequential Addition of Three Hyperthermophilic Enzymes. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2016; 64:1777-1783. [PMID: 26832825 DOI: 10.1021/acs.jafc.5b05648] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
α-Glucose 1-phosphate (G1P) is synthesized from 5% (w/v) corn starch and 1 M phosphate mediated by α-glucan phosphorylase (αGP) from the thermophilic bacterium Thermotoga maritima at pH 7.2 and 70 °C. To increase G1P yield from corn starch containing branched amylopectin, a hyper-thermostable isoamylase from Sulfolobus tokodaii was added for simultaneous starch gelatinization and starch-debranching hydrolysis at 85 °C and pH 5.5 before αGP use. The pretreatment of isoamylase increased G1P titer from 120 mM to 170 mM. To increase maltose and maltotriose utilization, the third thermostable enzyme, 4-glucanotransferase (4GT) from Thermococcus litoralis, was added during the late stage of G1P biotransformation, further increasing G1P titer to 200 mM. This titer is the highest G1P level obtained on starch or its derived products (maltodextrin and soluble starch). This study suggests that in vitro multienzyme biotransformation has an advantage of great engineering flexibility in terms of space and time compared with microbial fermentation.
Collapse
Affiliation(s)
- Wei Zhou
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences , 32 West Seventh Avenue, Tianjin Airport Economic Area, Tianjin 300308, China
| | - Chun You
- Cell Free Bioinnovations Inc. , 1800 Kraft Drive, Suite 222, Blacksburg, Virginia 24060, United States
| | - Hongwu Ma
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences , 32 West Seventh Avenue, Tianjin Airport Economic Area, Tianjin 300308, China
| | - Yanhe Ma
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences , 32 West Seventh Avenue, Tianjin Airport Economic Area, Tianjin 300308, China
| | - Y-H Percival Zhang
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences , 32 West Seventh Avenue, Tianjin Airport Economic Area, Tianjin 300308, China
- Cell Free Bioinnovations Inc. , 1800 Kraft Drive, Suite 222, Blacksburg, Virginia 24060, United States
- Biological Systems Engineering Department, Virginia Tech , 304 Seitz Hall, Blacksburg, Virginia 24061, United States
| |
Collapse
|
9
|
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]
|
10
|
Acceptor specificity of amylomaltase from Corynebacterium glutamicum and transglucosylation reaction to synthesize palatinose glucosides. Process Biochem 2015. [DOI: 10.1016/j.procbio.2015.07.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
11
|
Affinity purification of 4-α-glucanotransferase through formation of complex with insoluble amylose. Food Sci Biotechnol 2015. [DOI: 10.1007/s10068-015-0236-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
|
12
|
Biochemical Characterization of the Lactobacillus reuteri Glycoside Hydrolase Family 70 GTFB Type of 4,6-α-Glucanotransferase Enzymes That Synthesize Soluble Dietary Starch Fibers. Appl Environ Microbiol 2015; 81:7223-32. [PMID: 26253678 DOI: 10.1128/aem.01860-15] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2015] [Accepted: 07/31/2015] [Indexed: 11/20/2022] Open
Abstract
4,6-α-Glucanotransferase (4,6-α-GTase) enzymes, such as GTFB and GTFW of Lactobacillus reuteri strains, constitute a new reaction specificity in glycoside hydrolase family 70 (GH70) and are novel enzymes that convert starch or starch hydrolysates into isomalto/maltopolysaccharides (IMMPs). These IMMPs still have linear chains with some α1→4 linkages but mostly (relatively long) linear chains with α1→6 linkages and are soluble dietary starch fibers. 4,6-α-GTase enzymes and their products have significant potential for industrial applications. Here we report that an N-terminal truncation (amino acids 1 to 733) strongly enhances the soluble expression level of fully active GTFB-ΔN (approximately 75-fold compared to full-length wild type GTFB) in Escherichia coli. In addition, quantitative assays based on amylose V as the substrate are described; these assays allow accurate determination of both hydrolysis (minor) activity (glucose release, reducing power) and total activity (iodine staining) and calculation of the transferase (major) activity of these 4,6-α-GTase enzymes. The data show that GTFB-ΔN is clearly less hydrolytic than GTFW, which is also supported by nuclear magnetic resonance (NMR) analysis of their final products. From these assays, the biochemical properties of GTFB-ΔN were characterized in detail, including determination of kinetic parameters and acceptor substrate specificity. The GTFB enzyme displayed high conversion yields at relatively high substrate concentrations, a promising feature for industrial application.
Collapse
|
13
|
Chen F, Xie T, Yue Y, Qian S, Chao Y, Pei J. Molecular dynamic analysis of mutant Y195I α-cyclodextrin glycosyltransferase with switched product specificity from α-cyclodextrin to γ-cyclodextrin. J Mol Model 2015. [PMID: 26216223 DOI: 10.1007/s00894-015-2734-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Alpha-cyclodextrin (α-CD) glycosyltransferase (α-CGTase) can convert starch into α-CD blended with various proportions of β-cyclodextrin (β-CD) and/or γ-cyclodextrin (γ-CD). In this study, we verified the catalytic characteristics of purified Y195I α-CGTase and elucidated the mechanism of action with molecular dynamic (MD) simulations. We found that purified Y195I α-CGTase produced less α-CD, slightly more β-CD, and significantly more γ-CD than wild-type α-CGTase. Correspondingly, α-CD-based K m values increased, and β-CD- and γ-CD-based K m values decreased. MD simulation studies revealed that the dynamic trajectories of the substrate oligosaccharide chain in the mutant CGTase binding site were significantly different from those in the wild-type enzyme, with reduced hydrophobic interaction, finally resulting in different product specificity and more γ-CD formation.
Collapse
Affiliation(s)
- Fangjin Chen
- Center for Quantitative Biology, AAIS, Peking University, Beijing, China, 100871
| | | | | | | | | | | |
Collapse
|
14
|
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]
|
15
|
Expression and characterization of 4-α-glucanotransferase genes from Manihot esculenta Crantz and Arabidopsis thaliana and their use for the production of cycloamyloses. Process Biochem 2014. [DOI: 10.1016/j.procbio.2013.10.009] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
16
|
Han R, Li J, Shin HD, Chen RR, Du G, Liu L, Chen J. Recent advances in discovery, heterologous expression, and molecular engineering of cyclodextrin glycosyltransferase for versatile applications. Biotechnol Adv 2013; 32:415-28. [PMID: 24361954 DOI: 10.1016/j.biotechadv.2013.12.004] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2013] [Revised: 12/04/2013] [Accepted: 12/16/2013] [Indexed: 12/30/2022]
Abstract
Cyclodextrin glycosyltransferase (CGTase) is an important enzyme with multiple functions, in particular the production of cyclodextrins. It is also widely applied in baking and carbohydrate glycosylation because it participates in various types of catalytic reactions. New applications are being found with novel CGTases being isolated from various organisms. Heterologous expression is performed for the overproduction of CGTases to meet the requirements of these applications. In addition, various directed evolution techniques have been applied to modify the molecular structure of CGTase for improved performance in industrial applications. In recent years, substantial progress has been made in the heterologous expression and molecular engineering of CGTases. In this review, we systematically summarize the heterologous expression strategies used for enhancing the production of CGTases. We also outline and discuss the molecular engineering approaches used to improve the production, secretion, and properties (e.g., product and substrate specificity, catalytic efficiency, and thermal stability) of CGTase.
Collapse
Affiliation(s)
- Ruizhi Han
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China; Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China; Synergetic Innovation Center of Food Safety and Nutrition, Wuxi 214122, China
| | - Jianghua Li
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China; Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China; Synergetic Innovation Center of Food Safety and Nutrition, Wuxi 214122, China
| | - Hyun-Dong Shin
- School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta 30332, USA
| | - Rachel R Chen
- School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta 30332, USA
| | - Guocheng Du
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China; Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China; Synergetic Innovation Center of Food Safety and Nutrition, Wuxi 214122, China.
| | - Long Liu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China; Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China; Synergetic Innovation Center of Food Safety and Nutrition, Wuxi 214122, China.
| | - Jian Chen
- National Engineering of Laboratory for Cereal Fermentation Technology, Jiangnan University, Wuxi 214122, China
| |
Collapse
|
17
|
Iterative saturation mutagenesis of -6 subsite residues in cyclodextrin glycosyltransferase from Paenibacillus macerans to improve maltodextrin specificity for 2-O-D-glucopyranosyl-L-ascorbic acid synthesis. Appl Environ Microbiol 2013; 79:7562-8. [PMID: 24077706 DOI: 10.1128/aem.02918-13] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
2-O-d-Glucopyranosyl-l-ascorbic acid (AA-2G), a stable l-ascorbic acid derivative, is usually synthesized by cyclodextrin glycosyltransferase (CGTase), which contains nine substrate-binding subsites (from +2 to -7). In this study, iterative saturation mutagenesis (ISM) was performed on the -6 subsite residues (Y167, G179, G180, and N193) in the CGTase from Paenibacillus macerans to improve its specificity for maltodextrin, which is a cheap and easily soluble glycosyl donor for AA-2G synthesis. Site saturation mutagenesis of four sites-Y167, G179, G180, and N193-was first performed and revealed that four mutants-Y167S, G179R, N193R, and G180R-produced AA-2G yields higher than those of other mutant and wild-type CGTases. ISM was then conducted with the best positive mutant as a template. Under optimal conditions, mutant Y167S/G179K/N193R/G180R produced the highest AA-2G titer of 2.12 g/liter, which was 84% higher than that (1.15 g/liter) produced by the wild-type CGTase. Kinetics analysis of AA-2G synthesis using mutant CGTases confirmed the enhanced maltodextrin specificity and showed that compared to the wild-type CGTase, the mutants had no cyclization activity but high hydrolysis and disproportionation activities. A possible mechanism for the enhanced substrate specificity was also analyzed through structure modeling of the mutant and wild-type CGTases. These results indicated that the -6 subsite played crucial roles in the substrate binding and catalytic reactions of CGTase and that the obtained CGTase mutants, especially Y167S/G179K/N193R/G180R, are promising starting points for further development through protein engineering.
Collapse
|
18
|
Song B, Yue Y, Xie T, Qian S, Chao Y. Mutation of Tyrosine167Histidine at Remote Substrate Binding Subsite −6 in α-Cyclodextrin Glycosyltransferase Enhancing α-Cyclodextrin Specificity by Directed Evolution. Mol Biotechnol 2013; 56:232-9. [DOI: 10.1007/s12033-013-9699-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
|
19
|
Maltose-forming α-amylase from the hyperthermophilic archaeon Pyrococcus sp. ST04. Appl Microbiol Biotechnol 2013; 98:2121-31. [PMID: 23884203 DOI: 10.1007/s00253-013-5068-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2013] [Revised: 05/28/2013] [Accepted: 06/17/2013] [Indexed: 10/26/2022]
Abstract
The deduced amino acid sequence from a gene of the hyperthermophilic archaeon Pyrococcus sp. ST04 (Py04_0872) contained a conserved glycoside hydrolase family 57 (GH57) motif, but showed <13% sequence identity with other known Pyrococcus GH57 enzymes, such as 4-α-glucanotransferase (EC 2.4.1.25), amylopullulanase (EC 3.2.1.41), and branching enzyme (EC 2.4.1.18). This gene was cloned and expressed in Escherichia coli, and the recombinant product (Pyrococcus sp. ST04 maltose-forming α-amylase, PSMA) was a novel 70-kDa maltose-forming α-amylase. PSMA only recognized maltose (G2) units with α-1,4 and α-1,6 linkages in polysaccharides (e.g., starch, amylopectin, and glycogen) and hydrolyzed pullulan very poorly. G2 was the primary end product of hydrolysis. Branched cyclodextrin (CD) was only hydrolyzed along its branched maltooligosaccharides. 6-O-glucosyl-β-cyclodextrin (G1-β-CD) and β-cyclodextrin (β-CD) were resistant to PSMA suggesting that PSMA is an exo-type glucan hydrolase with α-1,4- and α-1,6-glucan hydrolytic activities. The half-saturation value (Km) for the α-1,4 linkage of maltotriose (G3) was 8.4 mM while that of the α-1,6 linkage of 6-O-maltosyl-β-cyclodextrin (G2-β-CD) was 0.3 mM. The kcat values were 381.0 min(-1) for G3 and 1,545.0 min(-1) for G2-β-CD. The enzyme was inhibited competitively by the reaction product G2, and the Ki constant was 0.7 mM. PSMA bridges the gap between amylases that hydrolyze larger maltodextrins and α-glucosidase that feeds G2 into glycolysis by hydrolyzing smaller glucans into G2 units.
Collapse
|
20
|
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.
Collapse
|
21
|
Ellouze F, Ben Amar N, Deratani A. Les cyclodextrines a large cycle : synthèse, purification et applications. CR CHIM 2011. [DOI: 10.1016/j.crci.2011.02.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
22
|
Jung JH, Jung TY, Seo DH, Yoon SM, Choi HC, Park BC, Park CS, Woo EJ. Structural and functional analysis of substrate recognition by the 250s loop in amylomaltase from Thermus brockianus. Proteins 2011; 79:633-44. [PMID: 21117235 DOI: 10.1002/prot.22911] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Amylomaltase, or 4-α-glucanotransferase (EC 2.4.1.25), is involved in glycogen and maltooligosaccharide metabolism in microorganisms, catalyzing both the hydrolysis and transfer of an α-1,4-oligosacchraride to other sugar molecules. In this study, we determined the crystal structure of amylomaltase from Thermus brockianus at a resolution of 2.3 Å and conducted a biochemical study to understand the detailed mechanism for its activity. Careful comparison with previous amylomaltase structures showed a pattern of conformational flexibility in the 250s loop with higher B-factor. Amylomaltase from T. brockianus exhibited a high transglycosylation factor for glucose and a lower value for maltose. Mutation of Gln256 resulted in increased K(m) for maltotriose and a sharp decrease of the transglycosylation factor for maltose, suggesting the involvement of Gln 256 in substrate binding between subsites +1 and +2. Mutation of Phe251 resulted in significantly lower glucose production but increased maltose production from maltopentose substrates, showing an altered substrate-binding affinity. The mutational data suggest the conformational flexibility of the loop may be involved in substrate binding in the GH77 family. Here, we present an action model of the 250s loop providing the molecular basis for the involvement of residues Phe251, Gln256, and Trp258 in the hydrolysis and transglycosylation activities in amylomaltase.
Collapse
Affiliation(s)
- Jong-Hyun Jung
- Graduate School of Biotechnology and Institute of Life Science and Resources, Kyung Hee University, Yongin 446-701, Korea
| | | | | | | | | | | | | | | |
Collapse
|
23
|
Cho KH, Auh JH, Ryu JH, Kim JH, Park K, Park CS, Yoo SH. Structural modification and characterization of rice starch treated by Thermus aquaticus 4-α-glucanotransferase. Food Hydrocoll 2009. [DOI: 10.1016/j.foodhyd.2009.06.019] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
|
24
|
Smoot JT, Demchenko AV. Oligosaccharide synthesis: from conventional methods to modern expeditious strategies. Adv Carbohydr Chem Biochem 2009; 62:161-250. [PMID: 19501706 DOI: 10.1016/s0065-2318(09)00005-5] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
- James T Smoot
- Department of Chemistry and Biochemistry, University of Missouri, St. Louis, MO 63121, USA
| | | |
Collapse
|
25
|
Lee BH, Oh DK, Yoo SH. Characterization of 4-alpha-glucanotransferase from Synechocystis sp. PCC 6803 and its application to various corn starches. N Biotechnol 2009; 26:29-36. [PMID: 19576307 DOI: 10.1016/j.nbt.2009.06.981] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2009] [Revised: 05/10/2009] [Accepted: 06/23/2009] [Indexed: 10/20/2022]
Abstract
A putative 4-alpha-glucanotransferase (alphaGTase) gene from Synechocystis sp. PCC 6803 was identified being composed of 1505 nucleotides, and the overexpressed protein was purified with an affinity chromatography. The recombinant alphaGTase had about 57kDa of molecular mass when judged by SDS-PAGE analysis. The optimum reaction condition of the alphaGTase was shown to be pH 7 at 45 degrees C in 50mm phosphate buffer. This enzyme displayed transglycosylating activity on various maltooligosaccharides, of which the smallest donor and acceptor molecules were determined to be maltose and glucose, respectively. Various corn starches consisting of different proportions of amylopectin and amylose were incubated with the recombinant alphaGTase. The change in molecular weight distribution of alphaGTase-modified starch was analyzed by HPSEC. The reaction pattern of alphaGTase showed substantial decrease in amylopectin and increase in the peak corresponding to cycloamylose (CA). The production yield of CA tended to increase from 5 to 30% along with the increase in the apparent amylose content in corn starch, which suggested that linear amylose chain would be preferred to produce CA in the alphaGTase treatment. The detectable minimum degree of polymerization (DP) of CA was shown to be 22 by MALDI-TOF-MS analysis. As another action mode of alphaGTase, the rearrangement of amylopectin branch-chain distribution occurred without hydrolysis to small oligosaccharides. After isoamylolysis, alphaGTase-treated starch displayed the increase in DP 4-9 and longer than DP 21 when the relative proportion of branch chains in amylopectin was determined by HPAEC.
Collapse
Affiliation(s)
- Byung-Hoo Lee
- Department of Food Science & Technology, BK21 Project Team, and Carbohydrate Bioproduct Research Center, Sejong University, 98 Gunja-Dong, Gwangjin-Gu, Seoul 143-747, Republic of Korea
| | | | | |
Collapse
|
26
|
Lee CK, Le QT, Kim YH, Shim JH, Lee SJ, Park JH, Lee KP, Song SH, Auh JH, Lee SJ, Park KH. Enzymatic synthesis and properties of highly branched rice starch amylose and amylopectin cluster. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2008; 56:126-131. [PMID: 18072737 DOI: 10.1021/jf072508s] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
We enzymatically modified rice starch to produce highly branched amylopectin and amylose and analyzed the resulting structural changes. To prepare the highly branched amylopectin cluster (HBAPC), we first treated waxy rice starch with Thermus scotoductus alpha-glucanotransferase (TSalphaGT), followed by treatment with Bacillus stearothermophilus maltogenic amylase (BSMA). Highly branched amylose (HBA) was prepared by incubating amylose with Bacillus subtilis 168 branching enzyme (BBE) and subsequently treating it with BSMA. The molecular weight of TSalphaGT-treated waxy rice starch was reduced from 8.9 x 10(8) to 1.2 x 10(5) Da, indicating that the alpha-1,4 glucosidic linkage of the segment between amylopectin clusters was hydrolyzed. Analysis of the amylopectin cluster side chains revealed that a rearrangement in the side-chain length distribution occurred. Furthermore, HBAPC and HBA were found to contain significant numbers of branched maltooligosaccharide side chains. In short, amylopectin molecules of waxy rice starch were hydrolyzed into amylopectin clusters by TSalphaGT in the enzymatic modification process, and then further branched by transglycosylation using BSMA. HBAPC and HBA showed higher water solubility and stability against retrogradation than amylopectin clusters or branched amylose. The hydrolysis rates of HBAPC and HBA by glucoamylase and alpha-amylase greatly decreased. The k cat/ K m value of glucoamylase acting on the amylopectin cluster was 45.94 s(-1)(mg/mL)(-1) and that for glucoamylase acting on HBAPC was 11.10 s(-1)(mg/mL)(-1), indicating that HBAPC was 4-fold less susceptible to glucoamylase. The k cat/ K m value for HBA was 15.90 s(-1)(mg/mL)(-1), or about three times less than that for branched amylose. The k cat/ K m values of porcine pancreatic alpha-amylase for HBAPC and HBA were 496 and 588 s(-1)(mg/mL)(-1), respectively, indicating that HBA and HBAPC are less susceptible to hydrolysis by glucoamylase and alpha-amylase. HBAPC and HBA show potential as novel glucan polymers with low digestibility and high water solubility.
Collapse
Affiliation(s)
- Chang-Kyu Lee
- Center for Agricultural Biomaterials and Department of Agricultural Biotechnology, Seoul National University, Gwanak-Gu, Seoul, Korea
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
27
|
Turner P, Mamo G, Karlsson EN. Potential and utilization of thermophiles and thermostable enzymes in biorefining. Microb Cell Fact 2007; 6:9. [PMID: 17359551 PMCID: PMC1851020 DOI: 10.1186/1475-2859-6-9] [Citation(s) in RCA: 317] [Impact Index Per Article: 18.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2007] [Accepted: 03/15/2007] [Indexed: 11/10/2022] Open
Abstract
In today's world, there is an increasing trend towards the use of renewable, cheap and readily available biomass in the production of a wide variety of fine and bulk chemicals in different biorefineries. Biorefineries utilize the activities of microbial cells and their enzymes to convert biomass into target products. Many of these processes require enzymes which are operationally stable at high temperature thus allowing e.g. easy mixing, better substrate solubility, high mass transfer rate, and lowered risk of contamination. Thermophiles have often been proposed as sources of industrially relevant thermostable enzymes. Here we discuss existing and potential applications of thermophiles and thermostable enzymes with focus on conversion of carbohydrate containing raw materials. Their importance in biorefineries is explained using examples of lignocellulose and starch conversions to desired products. Strategies that enhance thermostablity of enzymes both in vivo and in vitro are also assessed. Moreover, this review deals with efforts made on developing vectors for expressing recombinant enzymes in thermophilic hosts.
Collapse
Affiliation(s)
- Pernilla Turner
- Dept Biotechnology, Center for Chemistry and Chemical Engineering, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden
| | - Gashaw Mamo
- Dept Biotechnology, Center for Chemistry and Chemical Engineering, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden
| | - Eva Nordberg Karlsson
- Dept Biotechnology, Center for Chemistry and Chemical Engineering, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden
| |
Collapse
|
28
|
Park JH, Kim HJ, Kim YH, Cha H, Kim YW, Kim TJ, Kim YR, Park KH. The action mode of Thermus aquaticus YT-1 4-α-glucanotransferase and its chimeric enzymes introduced with starch-binding domain on amylose and amylopectin. Carbohydr Polym 2007. [DOI: 10.1016/j.carbpol.2006.05.018] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
29
|
Tang SY, Yang SJ, Cha H, Woo EJ, Park C, Park KH. Contribution of W229 to the transglycosylation activity of 4-α-glucanotransferase from Pyrococcus furiosus. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2006; 1764:1633-8. [PMID: 17035108 DOI: 10.1016/j.bbapap.2006.08.013] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2006] [Revised: 08/22/2006] [Accepted: 08/28/2006] [Indexed: 10/24/2022]
Abstract
A W229H mutant of 4-alpha-glucanotransferase (4-alpha-GTase) from Pyrococcus furiosus was constructed and its catalytic properties were studied to investigate the role of W229 in the catalytic specificities of the enzyme. Various activities and kinetic parameters were determined for the wild-type and W229H mutant enzymes. The transglycosylation factor and transglycosylation activity of the mutant enzyme markedly decreased, but its hydrolysis activity was scarcely affected. It was discovered that the k(cat)/K(m) value of transglycosylation activity significantly decreased to about 15% of that of the wild type, while k(cat)/K(m) value of hydrolysis activity changed little for the mutant enzyme. The hydrophobicity of W229 was thought to be critical to the transglycosylation activity of the enzyme based on the enzyme's modeled tertiary structures.
Collapse
Affiliation(s)
- Shuang-Yan Tang
- Center for Agricultural Biomaterials and Department of Food Science and Biotechnology, School of Agricultural Biotechnology, Seoul National University, Seoul 151-742, Korea
| | | | | | | | | | | |
Collapse
|
30
|
Atomi H. Microbial enzymes involved in carbon dioxide fixation. J Biosci Bioeng 2005; 94:497-505. [PMID: 16233341 DOI: 10.1016/s1389-1723(02)80186-4] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2002] [Accepted: 09/17/2002] [Indexed: 11/26/2022]
Abstract
This review focuses on the enzymes involved in two microbial carbon dioxide fixation pathways, the Calvin-Benson-Bassham cycle and the reductive tricarboxylic acid cycle. The function, structural features, and gene regulation of microbial ribulose 1,5-bisphosphate carboxylase/oxygenase (Rubisco), a key enzyme of the Calvin-Benson-Bassham cycle, is described. Some recent findings on Rubisco from archaea and Rubisco-like proteins are also outlined. In the final section, biochemical features of the key enzymes in the reductive tricarboxylic acid cycle are reviewed.
Collapse
Affiliation(s)
- Haruyuki Atomi
- Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Yoshida-Honmachi, Sakyo-ku, Kyoto 606-8501, Japan.
| |
Collapse
|
31
|
Imamura H, Fushinobu S, Yamamoto M, Kumasaka T, Jeon BS, Wakagi T, Matsuzawa H. Crystal structures of 4-alpha-glucanotransferase from Thermococcus litoralis and its complex with an inhibitor. J Biol Chem 2003; 278:19378-86. [PMID: 12618437 DOI: 10.1074/jbc.m213134200] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Thermococcus litoralis 4-alpha-glucanotransferase (TLGT) belongs to glucoside hydrolase family 57 and catalyzes the disproportionation of amylose and the formation of large cyclic alpha-1,4-glucan (cycloamylose) from linear amylose. We determined the crystal structure of TLGT with and without an inhibitor, acarbose. TLGT is composed of two domains: an N-terminal domain (domain I), which contains a (beta/alpha)7 barrel fold, and a C-terminal domain (domain II), which has a twisted beta-sandwich fold. In the structure of TLGT complexed with acarbose, the inhibitor was bound at the cleft within domain I, indicating that domain I is a catalytic domain of TLGT. The acarbose-bound structure also clarified that Glu123 and Asp214 were the catalytic nucleophile and acid/base catalyst, respectively, and revealed the residues involved in substrate binding. It seemed that TLGT produces large cyclic glucans by preventing the production of small cyclic glucans by steric hindrance, which is achieved by three lids protruding into the active site cleft, as well as an extended active site cleft. Interestingly, domain I of TLGT shares some structural features with the catalytic domain of Golgi alpha-mannosidase from Drosophila melanogaster, which belongs to glucoside hydrolase family 38. Furthermore, the catalytic residue of the two enzymes is located in the same position. These observations suggest that families 57 and 38 evolved from a common ancestor.
Collapse
Affiliation(s)
- Hiromi Imamura
- Department of Biotechnology, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan.
| | | | | | | | | | | | | |
Collapse
|
32
|
Yanase M, Takata H, Takaha T, Kuriki T, Smith SM, Okada S. Cyclization reaction catalyzed by glycogen debranching enzyme (EC 2.4.1.25/EC 3.2.1.33) and its potential for cycloamylose production. Appl Environ Microbiol 2002; 68:4233-9. [PMID: 12200270 PMCID: PMC124075 DOI: 10.1128/aem.68.9.4233-4239.2002] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Glycogen debranching enzyme (GDE) has 4-alpha-glucanotransferase and amylo-1,6-glucosidase activities in the single polypeptide chain. We analyzed the detailed action profile of GDE from Saccharomyces cerevisiae on amylose and tested whether GDE catalyzes cyclization of amylose. GDE treatment resulted in a rapid reduction of absorbance of iodine-amylose complex and the accumulation of a product that was resistant to an exo-amylase (glucoamylase [GA]) but was degraded by an endo-type alpha-amylase to glucose and maltose. These results indicated that GDE catalyzed cyclization of amylose to produce cyclic alpha-1,4 glucan (cycloamylose). The formation of cycloamylose was confirmed by high-performance anion-exchange chromatography, and the size was shown to range from a degree of polymerization of 11 to a degree of polymerization around 50. The minimum size and the size distribution of cycloamylose were different from those of cycloamylose produced by other 4-alpha-glucanotransferases. GDE also efficiently produced cycloamylose even from the branched glucan substrate, starch, demonstrating its potential for industrial production of cycloamylose.
Collapse
Affiliation(s)
- Michiyo Yanase
- Biochemical Research Laboratory, Ezaki Glico Co., Ltd., Nishiyodogawa-ku, Osaka 555-8502, Japan.
| | | | | | | | | | | |
Collapse
|