1
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Glycoside hydrolase family 18 chitinases: The known and the unknown. Biotechnol Adv 2020; 43:107553. [DOI: 10.1016/j.biotechadv.2020.107553] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Revised: 03/09/2020] [Accepted: 04/20/2020] [Indexed: 12/13/2022]
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2
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Chen W, Zhou Y, Yang Q. Structural dissection reveals a general mechanistic principle for group II chitinase (ChtII) inhibition. J Biol Chem 2019; 294:9358-9364. [PMID: 31053640 DOI: 10.1074/jbc.ra119.007812] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Revised: 04/30/2019] [Indexed: 12/13/2022] Open
Abstract
Small-molecule inhibitors of insect chitinases have potential applications for controlling insect pests. Insect group II chitinase (ChtII) is the most important chitinase in insects and functions throughout all developmental stages. However, the possibility of inhibiting ChtII by small molecules has not been explored yet. Here, we report the structural characteristics of four molecules that exhibited similar levels of inhibitory activity against OfChtII, a group II chitinase from the agricultural pest Asian corn borer Ostrinia furnacalis These inhibitors were chitooctaose ((GlcN)8), dipyrido-pyrimidine derivative (DP), piperidine-thienopyridine derivative (PT), and naphthalimide derivative (NI). The crystal structures of the OfChtII catalytic domain complexed with each of the four inhibitors at 1.4-2.0 Å resolutions suggested they all exhibit similar binding modes within the substrate-binding cleft; specifically, two hydrophobic groups of the inhibitor interact with +1/+2 tryptophan and a -1 hydrophobic pocket. The structure of the (GlcN)8 complex surprisingly revealed that the oligosaccharide chain of the inhibitor is orientated in the opposite direction to that previously observed in complexes with other chitinases. Injection of the inhibitors into 4th instar O. furnacalis larvae led to defects in development and pupation. The results of this study provide insights into a general mechanistic principle that confers inhibitory activity against ChtII, which could facilitate rational design of agrochemicals that target ecdysis of insect pests.
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Affiliation(s)
- Wei Chen
- From the State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, 2 West Yuanmingyuan Road, Beijing 100193, China and
| | - Yong Zhou
- School of Biotechnology and School of Software, Dalian University of Technology, 2 Linggong Road, Dalian 116024, China
| | - Qing Yang
- From the State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, 2 West Yuanmingyuan Road, Beijing 100193, China and .,School of Biotechnology and School of Software, Dalian University of Technology, 2 Linggong Road, Dalian 116024, China
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3
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Nakamura A, Okazaki KI, Furuta T, Sakurai M, Iino R. Processive chitinase is Brownian monorail operated by fast catalysis after peeling rail from crystalline chitin. Nat Commun 2018; 9:3814. [PMID: 30232340 PMCID: PMC6145945 DOI: 10.1038/s41467-018-06362-3] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Accepted: 08/29/2018] [Indexed: 12/02/2022] Open
Abstract
Processive chitinase is a linear molecular motor which moves on the surface of crystalline chitin driven by processive hydrolysis of single chitin chain. Here, we analyse the mechanism underlying unidirectional movement of Serratia marcescens chitinase A (SmChiA) using high-precision single-molecule imaging, X-ray crystallography, and all-atom molecular dynamics simulation. SmChiA shows fast unidirectional movement of ~50 nm s-1 with 1 nm forward and backward steps, consistent with the length of reaction product chitobiose. Analysis of the kinetic isotope effect reveals fast substrate-assisted catalysis with time constant of ~3 ms. Decrystallization of the single chitin chain from crystal surface is the rate-limiting step of movement with time constant of ~17 ms, achieved by binding free energy at the product-binding site of SmChiA. Our results demonstrate that SmChiA operates as a burnt-bridge Brownian ratchet wherein the Brownian motion along the single chitin chain is rectified forward by substrate-assisted catalysis.
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Grants
- JP15H06898 Ministry of Education, Culture, Sports, Science, and Technology (MEXT)
- JP17K18429 Ministry of Education, Culture, Sports, Science, and Technology (MEXT)
- JP17H05899 Ministry of Education, Culture, Sports, Science, and Technology (MEXT)
- JP16H00789 Ministry of Education, Culture, Sports, Science, and Technology (MEXT)
- JP16H00858 Ministry of Education, Culture, Sports, Science, and Technology (MEXT)
- JP17K19213 Ministry of Education, Culture, Sports, Science, and Technology (MEXT)
- JP18H05424 Ministry of Education, Culture, Sports, Science, and Technology (MEXT)
- JP15H04366 Ministry of Education, Culture, Sports, Science, and Technology (MEXT)
- 01311805 MEXT | National Institutes of Natural Sciences (NINS)
- J281002 MEXT | National Institutes of Natural Sciences (NINS)
- Advanced Technology Institute Research Grants (RG2709)
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Affiliation(s)
- Akihiko Nakamura
- Institute for Molecular Science, National Institutes of Natural Sciences, 444-8787, Okazaki, Aichi, Japan.
- Department of Functional Molecular Science, SOKENDAI (The Graduate University for Advanced Studies), Hayama, 240-0193, Japan.
| | - Kei-Ichi Okazaki
- Institute for Molecular Science, National Institutes of Natural Sciences, 444-8787, Okazaki, Aichi, Japan
| | - Tadaomi Furuta
- Center for Biological Resources and Informatics, Tokyo Institute of Technology, Yokohama, 226-8501, Japan
| | - Minoru Sakurai
- Center for Biological Resources and Informatics, Tokyo Institute of Technology, Yokohama, 226-8501, Japan
| | - Ryota Iino
- Institute for Molecular Science, National Institutes of Natural Sciences, 444-8787, Okazaki, Aichi, Japan.
- Department of Functional Molecular Science, SOKENDAI (The Graduate University for Advanced Studies), Hayama, 240-0193, Japan.
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4
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Blanco N, Sanz AB, Rodríguez-Peña JM, Nombela C, Farkaš V, Hurtado-Guerrero R, Arroyo J. Structural and functional analysis of yeast Crh1 and Crh2 transglycosylases. FEBS J 2015; 282:715-31. [DOI: 10.1111/febs.13176] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2014] [Revised: 10/28/2014] [Accepted: 12/11/2014] [Indexed: 11/28/2022]
Affiliation(s)
- Noelia Blanco
- Departamento de Microbiología II; Facultad de Farmacia; Universidad Complutense de Madrid; IRYCIS; Spain
| | - Ana B. Sanz
- Departamento de Microbiología II; Facultad de Farmacia; Universidad Complutense de Madrid; IRYCIS; Spain
| | - Jose M. Rodríguez-Peña
- Departamento de Microbiología II; Facultad de Farmacia; Universidad Complutense de Madrid; IRYCIS; Spain
| | - César Nombela
- Departamento de Microbiología II; Facultad de Farmacia; Universidad Complutense de Madrid; IRYCIS; Spain
| | - Vladimír Farkaš
- Department of Glycobiology; Center for Glycomics, Institute of Chemistry; Center for Glycomics; Slovak Academy of Sciences; Bratislava Slovakia
| | - Ramón Hurtado-Guerrero
- Institute of Biocomputation and Physics of Complex Systems (BIFI); University of Zaragoza; BIFI-IQFR (CSIC) Joint Unit; Spain
- Fundacion ARAID; Zaragoza Spain
| | - Javier Arroyo
- Departamento de Microbiología II; Facultad de Farmacia; Universidad Complutense de Madrid; IRYCIS; Spain
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5
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Vaaje-Kolstad G, Horn SJ, Sørlie M, Eijsink VGH. The chitinolytic machinery ofSerratia marcescens- a model system for enzymatic degradation of recalcitrant polysaccharides. FEBS J 2013; 280:3028-49. [DOI: 10.1111/febs.12181] [Citation(s) in RCA: 210] [Impact Index Per Article: 19.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2013] [Revised: 01/30/2013] [Accepted: 02/05/2013] [Indexed: 01/13/2023]
Affiliation(s)
- Gustav Vaaje-Kolstad
- Department of Chemistry; Biotechnology and Food Science; Norwegian University of Life Sciences; Ås; Norway
| | - Svein J. Horn
- Department of Chemistry; Biotechnology and Food Science; Norwegian University of Life Sciences; Ås; Norway
| | - Morten Sørlie
- Department of Chemistry; Biotechnology and Food Science; Norwegian University of Life Sciences; Ås; Norway
| | - Vincent G. H. Eijsink
- Department of Chemistry; Biotechnology and Food Science; Norwegian University of Life Sciences; Ås; Norway
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6
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Ishisaki K, Arai S, Hamada T, Honda Y. Biochemical characterization of a recombinant plant class III chitinase from the pitcher of the carnivorous plant Nepenthes alata. Carbohydr Res 2012; 361:170-4. [PMID: 23026711 DOI: 10.1016/j.carres.2012.09.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2012] [Revised: 08/21/2012] [Accepted: 09/02/2012] [Indexed: 10/27/2022]
Abstract
A class III chitinase belonging to the GH18 family from Nepenthes alata (NaCHIT3) was expressed in Escherichia coli. The enzyme exhibited hydrolytic activity toward colloidal chitin, ethylene glycol chitin, and (GlcNAc)(n) (n=5 and 6). The enzyme hydrolyzed the fourth glycosidic linkage from the non-reducing end of (GlcNAc)(6). The anomeric form of the products indicated it was a retaining enzyme. The colloidal chitin hydrolytic reaction displayed high activity between pH 3.9 and 6.9, but the pH optimum of the (GlcNAc)(6) hydrolytic reaction was 3.9 at 37 °C. The optimal temperature for activity was 65 °C in 50 mM sodium acetate buffer (pH 3.9). The pH optima of NaCHIT3 and NaCHIT1 might be related to their roles in chitin degradation in the pitcher fluid.
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Affiliation(s)
- Kana Ishisaki
- Department of Food Science, Ishikawa Prefectural University, 1-308, Suematsu, Nonoichi, Ishikawa 921-8836, Japan
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7
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A glycosynthase derived from an inverting GH19 chitinase from the moss Bryum coronatum. Biochem J 2012; 444:437-43. [DOI: 10.1042/bj20120036] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
BcChi-A, a GH19 chitinase from the moss Bryum coronatum, is an endo-acting enzyme that hydrolyses the glycosidic bonds of chitin, (GlcNAc)n [a β-1,4-linked polysaccharide of GlcNAc (N-acetylglucosamine) with a polymerization degree of n], through an inverting mechanism. When the wild-type enzyme was incubated with α-(GlcNAc)2-F [α-(GlcNAc)2 fluoride] in the absence or presence of (GlcNAc)2, (GlcNAc)2 and hydrogen fluoride were found to be produced through the Hehre resynthesis–hydrolysis mechanism. To convert BcChi-A into a glycosynthase, we employed the strategy reported by Honda et al. [(2006) J. Biol. Chem. 281, 1426–1431; (2008) Glycobiology 18, 325–330] of mutating Ser102, which holds a nucleophilic water molecule, and Glu70, which acts as a catalytic base, producing S102A, S102C, S102D, S102G, S102H, S102T, E70G and E70Q. In all of the mutated enzymes, except S102T, hydrolytic activity towards (GlcNAc)6 was not detected under the conditions we used. Among the inactive BcChi-A mutants, S102A, S102C, S102G and E70G were found to successfully synthesize (GlcNAc)4 as a major product from α-(GlcNAc)2-F in the presence of (GlcNAc)2. The S102A mutant showed the greatest glycosynthase activity owing to its enhanced F− releasing activity and its suppressed hydrolytic activity. This is the first report on a glycosynthase that employs amino sugar fluoride as a donor substrate.
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8
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Hattie M, Debowski AW, Stubbs KA. Development of tools to study lacto-N-biosidase: an important enzyme involved in the breakdown of human milk oligosaccharides. Chembiochem 2012; 13:1128-31. [PMID: 22514018 DOI: 10.1002/cbic.201200135] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2012] [Indexed: 01/15/2023]
Abstract
Milk and sugar? The elucidation of the catalytic mechanism and the development of the first known inhibitor for lacto-N-biosidases, which are important enzymes involved in the breakdown of human milk oligosaccharides, are described.
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Affiliation(s)
- Mitchell Hattie
- School of Chemistry and Biochemistry, University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia
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9
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Ishisaki K, Honda Y, Taniguchi H, Hatano N, Hamada T. Heterogonous expression and characterization of a plant class IV chitinase from the pitcher of the carnivorous plant Nepenthes alata. Glycobiology 2011; 22:345-51. [PMID: 21930651 DOI: 10.1093/glycob/cwr142] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
A class IV chitinase belonging to the glycoside hydrolase 19 family from Nepenthes alata (NaCHIT1) was expressed in Escherichia coli. The enzyme exhibited weak activity toward polymeric substrates and significant activity toward (GlcNAc)(n) [β-1,4-linked oligosaccharide of GlcNAc with a polymerization degree of n (n = 4-6)]. The enzyme hydrolyzed the third and fourth glycosidic linkages from the non-reducing end of (GlcNAc)(6). The pH optimum of the enzymatic reaction was 5.5 at 37°C. The optimal temperature for activity was 60°C in 50 mM sodium acetate buffer (pH 5.5). The anomeric form of the products indicated that it was an inverting enzyme. The k(cat)/K(m) of the (GlcNAc)(n) hydrolysis increased with an increase in the degree of polymerization. Amino acid sequence alignment analysis between NaCHIT1 and a class IV chitinase from a Picea abies (Norway spruce) suggested that the deletion of four loops likely led the enzyme to optimize the (GlcNAc)(n) hydrolytic reaction rather than the hydrolysis of polymeric substrates.
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Affiliation(s)
- Kana Ishisaki
- Department of Food Science, Ishikawa Prefectural University, 1-308, Suematsu, Nonoichi, Ishikawa 921-8836, Japan
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10
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Vuong TV, Wilson DB. Glycoside hydrolases: catalytic base/nucleophile diversity. Biotechnol Bioeng 2010; 107:195-205. [PMID: 20552664 DOI: 10.1002/bit.22838] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Recent studies have shown that a number of glycoside hydrolase families do not follow the classical catalytic mechanisms, as they lack a typical catalytic base/nucleophile. A variety of mechanisms are used to replace this function, including substrate-assisted catalysis, a network of several residues, and the use of non-carboxylate residues or exogenous nucleophiles. Removal of the catalytic base/nucleophile by mutation can have a profound impact on substrate specificity, producing enzymes with completely new functions.
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Affiliation(s)
- Thu V Vuong
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14850, USA
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11
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Li C, Huang W, Wang LX. Chemoenzymatic synthesis of N-linked neoglycoproteins through a chitinase-catalyzed transglycosylation. Bioorg Med Chem 2008; 16:8366-72. [PMID: 18783954 DOI: 10.1016/j.bmc.2008.08.042] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2008] [Revised: 08/17/2008] [Accepted: 08/20/2008] [Indexed: 10/21/2022]
Abstract
A novel application of the Bacillus sp. chitinase for the chemoenzymatic synthesis of N-linked neoglycoproteins is described. Three chitinases with different molecular size were purified from the crude chitinase preparation. The purified chitinases were evaluated for their hydrolytic and transglycosylation activity. One chitinase with a molecular size of 100 kDa (Chi100) was identified to be the one with highest transglycosylation/hydrolysis ratio. Chi100 could effectively recognize LacNAc-oxazoline and Manalpha1,3Glcbeta1,4GlcNAc-oxazoline as the donor substrate to glycosylate Asn-linked GlcNAc, while it was unable to recognize Manbeta1,4GlcNAc and Man(3)GlcNAc-oxazolines as the donor substrates. The chitinase-catalyzed transglycosylation was successfully extended to the remodeling of ribonuclease B to afford neoglycoproteins. Although the yield needs to be optimized, the chitinase-catalyzed transglycosylation provides a potentially useful tool for the synthesis of neoglycoproteins carrying novel N-linked oligosaccharides.
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Affiliation(s)
- Cishan Li
- Institute of Human Virology and Department of Biochemistry & Molecular Biology, University of Maryland School of Medicine, 725 West Lombard Street, Baltimore, MD 21201, USA
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12
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Bussink AP, van Eijk M, Renkema GH, Aerts JM, Boot RG. The biology of the Gaucher cell: the cradle of human chitinases. ACTA ACUST UNITED AC 2007; 252:71-128. [PMID: 16984816 DOI: 10.1016/s0074-7696(06)52001-7] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Gaucher disease (GD) is the most common lysosomal storage disorder and is caused by inherited deficiencies of glucocerebrosidase, the enzyme responsible for the lysosomal breakdown of the lipid glucosylceramide. GD is characterized by the accumulation of pathological, lipid laden macrophages, so-called Gaucher cells. Following the development of enzyme replacement therapy for GD, the search for suitable surrogate disease markers resulted in the identification of a thousand-fold increased chitinase activity in plasma from symptomatic Gaucher patients and that decreases upon successful therapeutic intervention. Biochemical investigations identified a single enzyme, named chitotriosidase, to be responsible for this activity. Chitotriosidase was found to be an excellent marker for lipid laden macrophages in Gaucher patients and is now widely used to assist clinical management of patients. In the wake of the identification of chitotriosidase, the presence of other members of the chitinase family in mammals was discovered. Amongst these is AMCase, an enzyme recently implicated in the pathogenesis of asthma. Chitinases are omnipresent throughout nature and are also produced by vertebrates in which they play important roles in defence against chitin-containing pathogens and in food processing.
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Affiliation(s)
- Anton P Bussink
- Department of Medical Biochemistry, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
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Boer H, Simolin H, Cottaz S, Söderlund H, Koivula A. Heterologous expression and site-directed mutagenesis studies of two Trichoderma harzianum chitinases, Chit33 and Chit42, in Escherichia coli. Protein Expr Purif 2006; 51:216-26. [PMID: 16997574 DOI: 10.1016/j.pep.2006.07.020] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2006] [Revised: 07/26/2006] [Accepted: 07/27/2006] [Indexed: 10/24/2022]
Abstract
Heterologous expression of two fungal chitinases, Chit33 and Chit42, from Trichoderma harzianum was tested in the different compartments and on the surface of Escherichia coli cells. Our goal was to find a fast and efficient expression system for protein engineering and directed evolution studies of the two fungal enzymes. Cytoplasmic overexpression resulted in both cases in inclusion body formation, where active enzyme could be recovered after refolding. Periplasmic expression of Chit33, and especially of Chit42, proved to be better suited for mutagenesis purposes. Recombinant chitinases from the periplasmic expression system showed activity profiles similar to those of the native proteins. Both chitinases also degraded a RET (resonance energy transfer) based bifunctionalized chitinpentaose substrate in a similar manner as reported for some putative exochitinases in the glycosyl hydrolase family 18, offering a sensitive way to assay their activities. We further demonstrated that Chit42 can also be displayed on E. coli surface and the enzymatic activity can be measured directly from the whole cells using methylumbelliferyl-chitinbioside as a substrate. The periplasmic expression and the surface display of Chit42, both offer a suitable expression system for protein engineering and activity screening in a microtiter plate scale. As a first mutagenesis approach we verified the essential role of the two carboxylic acid residues E172 (putative proton donor) and D170 (putative stabilizer) in the catalytic mechanism of Chit42, and additionally the role of the carboxylic acid E145 (putative proton donor) in the catalytic mechanism of Chit33.
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Affiliation(s)
- Harry Boer
- VTT Technical Research Centre of Finland, P.O. Box 1000, FI-02044 VTT, Finland.
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Schwarz A, Pierfederici F, Nidetzky B. Catalytic mechanism of alpha-retaining glucosyl transfer by Corynebacterium callunae starch phosphorylase: the role of histidine-334 examined through kinetic characterization of site-directed mutants. Biochem J 2005; 387:437-45. [PMID: 15535798 PMCID: PMC1134972 DOI: 10.1042/bj20041593] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Purified site-directed mutants of Corynebacterium callunae starch phosphorylase in which His-334 was replaced by an alanine, glutamine or asparagine residue were characterized by steady-state kinetic analysis of enzymic glycosyl transfer to and from phosphate and studies of ligand binding to the active site. Compared with wild-type, the catalytic efficiencies for phosphorolysis of starch at 30 degrees C and pH 7.0 decreased approx. 150- and 50-fold in H334Q (His334-->Gln) and H334N mutants, and that of H334A was unchanged. In the direction of alpha-glucan synthesis, selectivity for the reaction with G1P (alpha-D-glucose 1-phosphate) compared with the selectivity for reaction with alpha-D-xylose 1-phosphate decreased from a wild-type value of approximately 20000 to 2600 and 100 in H334N and H334Q respectively. Binding of G1P to the free enzyme was weakened between 10-fold (H334N, H334Q) and 50-fold (H334A) in the mutants, whereas binding to the complex of enzyme and alpha-glucan was not affected. Quenching of fluorescence of the pyridoxal 5'-phosphate cofactor was used to examine interactions of the inhibitor GL (D-gluconic acid 1,5-lactone) with wild-type and mutant enzymes in transient and steady-state experiments. GL binding to the free enzyme and the enzyme-phosphate complex occurred in a single step. The 50-fold higher constant (K(d)) for GL dissociation from H334Q bound to phosphate resulted from an increased off-rate for the ligand in the mutant, compared with wild-type. A log-log correlation of catalytic-centre activity for phosphorolysis of starch with a reciprocal K(d) value established a linear free-energy relationship (slope=1.19+/-0.07; r2=0.991) across the series of wild-type and mutant enzymes. It reveals that GL in combination with phosphate has properties of a transition state analogue and that the His-334 side chain has a role in selectively stabilizing the transition state of the reaction.
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Affiliation(s)
- Alexandra Schwarz
- Institute of Biotechnology and Biochemical Engineering, Graz University of Technology, Petersgasse 12, A-8010 Graz, Austria
| | - Francesco Maria Pierfederici
- Institute of Biotechnology and Biochemical Engineering, Graz University of Technology, Petersgasse 12, A-8010 Graz, Austria
| | - Bernd Nidetzky
- Institute of Biotechnology and Biochemical Engineering, Graz University of Technology, Petersgasse 12, A-8010 Graz, Austria
- To whom correspondence should be addressed (email )
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15
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Andersen OA, Dixon MJ, Eggleston IM, van Aalten DMF. Natural product family 18 chitinase inhibitors. Nat Prod Rep 2005; 22:563-79. [PMID: 16193156 DOI: 10.1039/b416660b] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- Ole A Andersen
- Division of Biological Chemistry & Molecular Microbiology, School of Life Sciences, University of Dundee, Dundee, Scotland DD1 5EH
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