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Shen J, Li J, Zhang Y, Mei X, Xue C, Chang Y. Characterization of an α-L-fucosidase in marine bacterium Wenyingzhuangia fucanilytica: new evidence on the catalytic sites of GH95 family glycosidases. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2024. [PMID: 38932571 DOI: 10.1002/jsfa.13659] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2024] [Revised: 05/08/2024] [Accepted: 06/01/2024] [Indexed: 06/28/2024]
Abstract
BACKGROUND α-l-Fucose confers unique functions for fucose-containing biomolecules such as human milk oligosaccharides. α-l-Fucosidases can serve as desirable tools in the application of fucosylated saccharides. Discovering novel α-l-fucosidases and elucidating their enzyme properties are always worthy tasks. RESULTS A GH95 family α-l-fucosidase named Afc95A_Wf was cloned from the genome of the marine bacterium Wenyingzhuangia fucanilytica and expressed in Escherichia coli. It exhibited maximum activity at 40 °C and pH 7.5. Afc95A_Wf defined a different substrate specificity among reported α-l-fucosidases, which was capable of hydrolyzing α-fucoside in CNP-fucose, Fucα1-2Galβ1-4Glc and Galβ1-4(Fucα1-3)Glc, and showed a preference for α1,2-fucosidic linkage. It adopted Asp residue in the amino acid sequence at position 391, which was distinct from the previously acknowledged residue of Asn. The predicted tertiary structure and site-directed mutagenesis revealed that Asp391 participates in the catalysis of Afc95A_Wf. The differences in the substrate specificity and catalytic site shed light on that Afc95A_Wf adopted a novel mechanism in catalysis. CONCLUSION A GH95 family α-l-fucosidase (Afc95A_Wf) was cloned and expressed. It showed a cleavage preference for α1,2-fucosidic linkage to α1,3-fucosidic linkage. Afc95A_Wf demonstrated a different substrate specificity and a residue at an important catalytic site compared with known GH95 family proteins, which revealed the occurrence of diversity on catalytic mechanisms in the GH95 family. © 2024 Society of Chemical Industry.
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Affiliation(s)
- Jingjing Shen
- College of Food Science and Engineering, Ocean University of China, Qingdao, China
| | - Jiajing Li
- College of Food Science and Engineering, Ocean University of China, Qingdao, China
| | - Yuying Zhang
- College of Food Science and Engineering, Ocean University of China, Qingdao, China
| | - Xuanwei Mei
- College of Food Science and Engineering, Ocean University of China, Qingdao, China
| | - Changhu Xue
- College of Food Science and Engineering, Ocean University of China, Qingdao, China
| | - Yaoguang Chang
- College of Food Science and Engineering, Ocean University of China, Qingdao, China
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2
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Hu C, Wang Y, Wang W, Cui W, Jia X, Mayo KH, Zhou Y, Su J, Yuan Y. A trapped covalent intermediate as a key catalytic element in the hydrolysis of a GH3 β-glucosidase: An X-ray crystallographic and biochemical study. Int J Biol Macromol 2024; 265:131131. [PMID: 38527679 DOI: 10.1016/j.ijbiomac.2024.131131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2024] [Revised: 03/21/2024] [Accepted: 03/22/2024] [Indexed: 03/27/2024]
Abstract
Glycoside hydrolases (GHs) are industrially important enzymes that hydrolyze glycosidic bonds in glycoconjugates. In this study, we found a GH3 β-glucosidase (CcBgl3B) from Cellulosimicrobium cellulans sp. 21 was able to selectively hydrolyze the β-1,6-glucosidic bond linked glucose of ginsenosides. X-ray crystallographic studies of the ligand complex ginsenoside-specific β-glucosidase provided a novel finding that support the catalytic mechanism of GH3. The substrate was clearly identified within the catalytic center of wild-type CcBgl3B, revealing that the C1 atom of the glucose was covalently bound to the Oδ1 group of the conserved catalytic nucleophile Asp264 as an enzyme-glycosyl intermediate. The glycosylated Asp264 could be identified by mass spectrometry. Through site-directed mutagenesis studies with Asp264, it was found that the covalent intermediate state formed by Asp264 and the substrate was critical for catalysis. In addition, Glu525 variants (E525A, E525Q and E525D) showed no or marginal activity against pNPβGlc; thus, this residue could supply a proton for the reaction. Overall, our study provides an insight into the catalytic mechanism of the GH3 enzyme CcBgl3B.
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Affiliation(s)
- Chenxing Hu
- Engineering Research Center of Glycoconjugates Ministry of Education, Jilin Provincial Key Laboratory of Chemistry and Biology of Changbai Mountain Natural Drugs, School of Life Sciences, Northeast Normal University, Changchun 130024, China
| | - Yibing Wang
- Engineering Research Center of Glycoconjugates Ministry of Education, Jilin Provincial Key Laboratory of Chemistry and Biology of Changbai Mountain Natural Drugs, School of Life Sciences, Northeast Normal University, Changchun 130024, China
| | - Weiyang Wang
- College of Life Science and Technology, Changchun University of Science & Technology, Changchun, Jilin 130022, China
| | - Wanli Cui
- Engineering Research Center of Glycoconjugates Ministry of Education, Jilin Provincial Key Laboratory of Chemistry and Biology of Changbai Mountain Natural Drugs, School of Life Sciences, Northeast Normal University, Changchun 130024, China
| | - Xinyue Jia
- Engineering Research Center of Glycoconjugates Ministry of Education, Jilin Provincial Key Laboratory of Chemistry and Biology of Changbai Mountain Natural Drugs, School of Life Sciences, Northeast Normal University, Changchun 130024, China
| | - Kevin H Mayo
- Department of Biochemistry, Molecular Biology & Biophysics, 6-155 Jackson Hall, University of Minnesota, Minneapolis, MN 55455, USA
| | - Yifa Zhou
- Engineering Research Center of Glycoconjugates Ministry of Education, Jilin Provincial Key Laboratory of Chemistry and Biology of Changbai Mountain Natural Drugs, School of Life Sciences, Northeast Normal University, Changchun 130024, China
| | - Jiyong Su
- Engineering Research Center of Glycoconjugates Ministry of Education, Jilin Provincial Key Laboratory of Chemistry and Biology of Changbai Mountain Natural Drugs, School of Life Sciences, Northeast Normal University, Changchun 130024, China.
| | - Ye Yuan
- Engineering Research Center of Glycoconjugates Ministry of Education, Jilin Provincial Key Laboratory of Chemistry and Biology of Changbai Mountain Natural Drugs, School of Life Sciences, Northeast Normal University, Changchun 130024, China.
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The evolutionary advantage of an aromatic clamp in plant family 3 glycoside exo-hydrolases. Nat Commun 2022; 13:5577. [PMID: 36151080 PMCID: PMC9508125 DOI: 10.1038/s41467-022-33180-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Accepted: 09/03/2022] [Indexed: 11/08/2022] Open
Abstract
In the barley β-D-glucan glucohydrolase, a glycoside hydrolase family 3 (GH3) enzyme, the Trp286/Trp434 clamp ensures β-D-glucosides binding, which is fundamental for substrate hydrolysis during plant growth and development. We employ mutagenesis, high-resolution X-ray crystallography, and multi-scale molecular modelling methods to examine the binding and conformational behaviour of isomeric β-D-glucosides during substrate-product assisted processive catalysis that operates in GH3 hydrolases. Enzyme kinetics reveals that the W434H mutant retains broad specificity, while W434A behaves as a strict (1,3)-β-D-glucosidase. Investigations of reactant movements on the nanoscale reveal that processivity is sensitive to mutation-specific alterations of the tryptophan clamp. While wild-type and W434H utilise a lateral cavity for glucose displacement and sliding of (1,3)-linked hydrolytic products through the catalytic site without dissociation, consistent with their high hydrolytic rates, W434A does not adopt processive catalysis. Phylogenomic analyses of GH3 hydrolases disclose the evolutionary advantage of the tryptophan clamp that confers broad specificity, high catalytic efficiency, and processivity.
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4
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Vacariu CM, Tanner ME. Recent Advances in the Synthesis and Biological Applications of Peptidoglycan Fragments. Chemistry 2022; 28:e202200788. [PMID: 35560956 DOI: 10.1002/chem.202200788] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Indexed: 11/09/2022]
Abstract
The biosynthesis, breakdown, and modification of peptidoglycan (PG) play vital roles in both bacterial viability and in the response of human physiology to bacterial infection. Studies on PG biochemistry are hampered by the fact that PG is an inhomogeneous insoluble macromolecule. Chemical synthesis is therefore an important means to obtain PG fragments that may serve as enzyme substrates and elicitors of the human immune response. This review outlines the recent advances in the synthesis and biochemical studies of PG fragments, PG biosynthetic intermediates (such as Park's nucleotides and PG lipids), and PG breakdown products (such as muramyl dipeptides and anhydro-muramic acid-containing fragments). A rich variety of synthetic approaches has been applied to preparing such compounds since carbohydrate, peptide, and phospholipid chemical methodologies must all be applied.
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Affiliation(s)
- Condurache M Vacariu
- Department of Chemistry, University of British Columbia, V6T 1Z1, Vancouver, British Columbia, Canada
| | - Martin E Tanner
- Department of Chemistry, University of British Columbia, V6T 1Z1, Vancouver, British Columbia, Canada
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Neun S, Brear P, Campbell E, Tryfona T, El Omari K, Wagner A, Dupree P, Hyvönen M, Hollfelder F. Functional metagenomic screening identifies an unexpected β-glucuronidase. Nat Chem Biol 2022; 18:1096-1103. [PMID: 35799064 DOI: 10.1038/s41589-022-01071-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Accepted: 05/25/2022] [Indexed: 11/09/2022]
Abstract
The abundance of recorded protein sequence data stands in contrast to the small number of experimentally verified functional annotation. Here we screened a million-membered metagenomic library at ultrahigh throughput in microfluidic droplets for β-glucuronidase activity. We identified SN243, a genuine β-glucuronidase with little homology to previously studied enzymes of this type, as a glycoside hydrolase 3 family member. This glycoside hydrolase family contains only one recently added β-glucuronidase, showing that a functional metagenomic approach can shed light on assignments that are currently 'unpredictable' by bioinformatics. Kinetic analyses of SN243 characterized it as a promiscuous catalyst and structural analysis suggests regions of divergence from homologous glycoside hydrolase 3 members creating a wide-open active site. With a screening throughput of >107 library members per day, picolitre-volume microfluidic droplets enable functional assignments that complement current enzyme database dictionaries and provide bridgeheads for the annotation of unexplored sequence space.
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Affiliation(s)
- Stefanie Neun
- Department of Biochemistry, University of Cambridge, Cambridge, UK
| | - Paul Brear
- Department of Biochemistry, University of Cambridge, Cambridge, UK
| | - Eleanor Campbell
- Department of Biochemistry, University of Cambridge, Cambridge, UK.,Australian Synchrotron, Clayton, VIC, Australia
| | - Theodora Tryfona
- Department of Biochemistry, University of Cambridge, Cambridge, UK
| | - Kamel El Omari
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, UK
| | - Armin Wagner
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, UK
| | - Paul Dupree
- Department of Biochemistry, University of Cambridge, Cambridge, UK
| | - Marko Hyvönen
- Department of Biochemistry, University of Cambridge, Cambridge, UK
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Fungal cellulases: protein engineering and post-translational modifications. Appl Microbiol Biotechnol 2021; 106:1-24. [PMID: 34889986 DOI: 10.1007/s00253-021-11723-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2021] [Revised: 11/28/2021] [Accepted: 11/30/2021] [Indexed: 12/18/2022]
Abstract
Enzymatic degradation of lignocelluloses into fermentable sugars to produce biofuels and other biomaterials is critical for environmentally sustainable development and energy resource supply. However, there are problems in enzymatic cellulose hydrolysis, such as the complex cellulase composition, low degradation efficiency, high production cost, and post-translational modifications (PTMs), all of which are closely related to specific characteristics of cellulases that remain unclear. These problems hinder the practical application of cellulases. Due to the rapid development of computer technology in recent years, computer-aided protein engineering is being widely used, which also brings new opportunities for the development of cellulases. Especially in recent years, a large number of studies have reported on the application of computer-aided protein engineering in the development of cellulases; however, these articles have not been systematically reviewed. This article focused on the aspect of protein engineering and PTMs of fungal cellulases. In this manuscript, the latest literatures and the distribution of potential sites of cellulases for engineering have been systematically summarized, which provide reference for further improvement of cellulase properties. KEY POINTS: •Rational design based on virtual mutagenesis can improve cellulase properties. •Modifying protein side chains and glycans helps obtain superior cellulases. •N-terminal glutamine-pyroglutamate conversion stabilizes fungal cellulases.
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Functional and structural characterization of a GH3 β-N-acetylhexosaminidase from Akkermansia muciniphila involved in mucin degradation. Biochem Biophys Res Commun 2021; 589:186-191. [PMID: 34922201 DOI: 10.1016/j.bbrc.2021.12.022] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2021] [Accepted: 12/07/2021] [Indexed: 01/06/2023]
Abstract
Akkermansia muciniphila is a probiotic that colonizes the outer layer of intestinal mucus and is negatively associated with metabolic disorders. Amuc_2109 protein, a β-N-acetylhexosaminidase from A. muciniphila, may be involved in the degradation of mucins and is associated with intestinal health. Here, we reported the crystal structure of Amuc_2109, which belongs to the GH family 3 enzymes and fell into the canonical (α/β)8 TIM barrel structure with GlcNAc bound to the active center. Biochemical assay characterization of Amuc_2109 revealed that Amuc_2109 is a GlcNAc-specific glycosidase active over a wide temperature and pH range, reflecting the survival advantage of Amuc_2109 in the intestinal environment. Our structural and biochemical results will contribute to the understanding of the catalytic mechanism of the GH3 β-N-acetylhexosaminidase and help to gain insight into the molecular mechanism of complex carbohydrate utilization and restoration of the intestinal barrier in A. muciniphila.
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Itoh T. Structures and functions of carbohydrate-active enzymes of chitinolytic bacteria Paenibacillus sp. str. FPU-7. Biosci Biotechnol Biochem 2021; 85:1314-1323. [PMID: 33792636 DOI: 10.1093/bbb/zbab058] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Accepted: 03/22/2021] [Indexed: 11/14/2022]
Abstract
Chitin and its derivatives have valuable potential applications in various fields that include medicine, agriculture, and food industries. Paenibacillus sp. str. FPU-7 is one of the most potent chitin-degrading bacteria identified. This review introduces the chitin degradation system of P. str. FPU-7. In addition to extracellular chitinases, P. str. FPU-7 uses a unique multimodular chitinase (ChiW) to hydrolyze chitin to oligosaccharides on the cell surface. Chitin oligosaccharides are converted to N-acetyl-d-glucosamine by β-N-acetylhexosaminidase (PsNagA) in the cytosol. The functions and structures of ChiW and PsNagA are also summarized. The genome sequence of P. str. FPU-7 provides opportunities to acquire novel enzymes. Genome mining has identified a novel alginate lyase, PsAly. The functions and structure of PsAly are reviewed. These findings will inform further improvement of the sustainable conversion of polysaccharides to functional materials.
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Affiliation(s)
- Takafumi Itoh
- Department of Bioscience and Biotechnology, Fukui Prefectural University, Yoshida-gun, Fukui, Japan
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9
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Kao MR, Yu SM, Ho THUD. Improvements of the productivity and saccharification efficiency of the cellulolytic β-glucosidase D2-BGL in Pichia pastoris via directed evolution. BIOTECHNOLOGY FOR BIOFUELS 2021; 14:126. [PMID: 34059121 PMCID: PMC8166090 DOI: 10.1186/s13068-021-01973-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Accepted: 05/17/2021] [Indexed: 05/02/2023]
Abstract
BACKGROUND β-Glucosidases are essential for cellulose hydrolysis by catalyzing the final cellulolytic degradation of cello-oligomers and cellobiose to glucose. D2-BGL is a fungal glycoside hydrolase family 3 (GH3) β-glucosidase isolated from Chaetomella raphigera with high substrate affinity, and is an efficient β-glucosidase supplement to Trichoderma reesei cellulase mixtures for the saccharification of lignocellulosic biomass. RESULTS We have carried out error-prone PCR to further increase catalytic efficiency of wild-type (WT) D2-BGL. Three mutants, each with substitution of two amino acids on D2-BGL, exhibited increased activity in a preliminary mutant screening in Saccharomyces cerevisiae. Effects of single amino acid replacements on catalysis efficiency and enzyme production have been investigated by subsequent expression in Pichia pastoris. Substitution F256M resulted in enhancing the tolerance to substrate inhibition and specific activity, and substitution D224G resulted in increasing the production of recombinant enzyme. The best D2-BGL mutant generated, Mut M, was constructed by combining beneficial mutations D224G, F256M and Y260D. Expression of Mut M in Pichia pastoris resulted in 2.7-fold higher production of recombinant protein, higher Vmax and greater substrate inhibition tolerance towards cellobiose relative to wild-type enzyme. Surprisingly, Mut M overexpression induced the ER unfolded protein response to a level lower than that with WT D2 overexpression in P. pastoris. When combined with the T. reesei cellulase preparation Celluclast 1.5L, Mut M hydrolyzed acid-pretreated sugarcane bagasse more efficiently than WT D2. CONCLUSIONS D2-BGL mutant Mut M was generated successfully by following directed evolution approach. Mut M carries three mutations that are not reported in other directed evolution studies of GH3 β-glucosidases, and this mutant exhibited greater tolerance to substrate inhibition and higher Vmax than wild-type enzyme. Besides the enhanced specific activity, Mut M also exhibited a higher protein titer than WT D2 when it was overexpressed in P. pastoris. Our study demonstrates that both catalytic efficiency and productivity of a cellulolytic enzyme can be enhanced via protein engineering.
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Affiliation(s)
- Mu-Rong Kao
- Molecular and Cell Biology, Taiwan International Graduate Program, Academia Sinica and National Defense Medical Center, Taipei, 115 Taiwan
- Institute of Molecular Biology, Academia Sinica, Taipei, 115 Taiwan
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, 115 Taiwan
| | - Su-May Yu
- Institute of Molecular Biology, Academia Sinica, Taipei, 115 Taiwan
- Department of Plant Pathology, National Chung Hsing University, Taichung, 402 Taiwan
- Department of Life Sciences, National Chung Hsing University, Taichung, 402 Taiwan
- Biotechnology Center, National Chung Hsing University, Taichung, 402 Taiwan
| | - Tuan-H ua David Ho
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, 115 Taiwan
- Biotechnology Center, National Chung Hsing University, Taichung, 402 Taiwan
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Franceus J, Lormans J, Cools L, D’hooghe M, Desmet T. Evolution of Phosphorylases from N-Acetylglucosaminide Hydrolases in Family GH3. ACS Catal 2021. [DOI: 10.1021/acscatal.1c00761] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Jorick Franceus
- Centre for Synthetic Biology (CSB), Department of Biotechnology, Ghent University, Coupure Links 653, B-9000 Ghent, Belgium
| | - Jolien Lormans
- Centre for Synthetic Biology (CSB), Department of Biotechnology, Ghent University, Coupure Links 653, B-9000 Ghent, Belgium
| | - Lore Cools
- SynBioC Research Group, Department of Green Chemistry and Technology, Ghent University, Coupure Links 653, B-9000 Ghent, Belgium
| | - Matthias D’hooghe
- SynBioC Research Group, Department of Green Chemistry and Technology, Ghent University, Coupure Links 653, B-9000 Ghent, Belgium
| | - Tom Desmet
- Centre for Synthetic Biology (CSB), Department of Biotechnology, Ghent University, Coupure Links 653, B-9000 Ghent, Belgium
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Müller M, Calvert M, Hottmann I, Kluj RM, Teufel T, Balbuchta K, Engelbrecht A, Selim KA, Xu Q, Borisova M, Titz A, Mayer C. The exo-β-N-acetylmuramidase NamZ from Bacillus subtilis is the founding member of a family of exo-lytic peptidoglycan hexosaminidases. J Biol Chem 2021; 296:100519. [PMID: 33684445 PMCID: PMC8054146 DOI: 10.1016/j.jbc.2021.100519] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Revised: 02/27/2021] [Accepted: 03/04/2021] [Indexed: 11/11/2022] Open
Abstract
Endo-β-N-acetylmuramidases, commonly known as lysozymes, are well-characterized antimicrobial enzymes that catalyze an endo-lytic cleavage of peptidoglycan; i.e., they hydrolyze the β-1,4-glycosidic bonds connecting N-acetylmuramic acid (MurNAc) and N-acetylglucosamine (GlcNAc). In contrast, little is known about exo-β-N-acetylmuramidases, which catalyze an exo-lytic cleavage of β-1,4-MurNAc entities from the non-reducing ends of peptidoglycan chains. Such an enzyme was identified earlier in the bacterium Bacillus subtilis, but the corresponding gene has remained unknown so far. We now report that ybbC of B. subtilis, renamed namZ, encodes the reported exo-β-N-acetylmuramidase. A ΔnamZ mutant accumulated specific cell wall fragments and showed growth defects under starvation conditions, indicating a role of NamZ in cell wall turnover and recycling. Recombinant NamZ protein specifically hydrolyzed the artificial substrate para-nitrophenyl β-MurNAc and the peptidoglycan-derived disaccharide MurNAc-β-1,4-GlcNAc. Together with the exo-β-N-acetylglucosaminidase NagZ and the exo-muramoyl-l-alanine amidase AmiE, NamZ degraded intact peptidoglycan by sequential hydrolysis from the non-reducing ends. A structure model of NamZ, built on the basis of two crystal structures of putative orthologs from Bacteroides fragilis, revealed a two-domain structure including a Rossmann-fold-like domain that constitutes a unique glycosidase fold. Thus, NamZ, a member of the DUF1343 protein family of unknown function, is now classified as the founding member of a new family of glycosidases (CAZy GH171; www.cazy.org/GH171.html). NamZ-like peptidoglycan hexosaminidases are mainly present in the phylum Bacteroidetes and less frequently found in individual genomes within Firmicutes (Bacilli, Clostridia), Actinobacteria, and γ-proteobacteria.
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Affiliation(s)
- Maraike Müller
- Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen, Tübingen, Germany
| | - Matthew Calvert
- Chemical Biology of Carbohydrates, Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Centre for Infection Research (HZI), Saarbrücken, Germany; Deutsches Zentrum für Infektionsforschung (DZIF), Standort Hannover-Braunschweig, Germany; Department of Chemistry, Saarland University, Saarbrücken, Germany
| | - Isabel Hottmann
- Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen, Tübingen, Germany
| | - Robert Maria Kluj
- Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen, Tübingen, Germany
| | - Tim Teufel
- Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen, Tübingen, Germany
| | - Katja Balbuchta
- Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen, Tübingen, Germany
| | - Alicia Engelbrecht
- Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen, Tübingen, Germany
| | - Khaled A Selim
- Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen, Tübingen, Germany; Chemistry of Natural and Microbial Products Department, Pharmaceutical and Drug Industries Research Division, National Research Center, Giza, Egypt
| | - Qingping Xu
- GM/CA @ APS, Argonne National Laboratory, Lemont, Illinois, USA
| | - Marina Borisova
- Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen, Tübingen, Germany
| | - Alexander Titz
- Chemical Biology of Carbohydrates, Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Centre for Infection Research (HZI), Saarbrücken, Germany; Deutsches Zentrum für Infektionsforschung (DZIF), Standort Hannover-Braunschweig, Germany; Department of Chemistry, Saarland University, Saarbrücken, Germany
| | - Christoph Mayer
- Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen, Tübingen, Germany.
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Rajasekaran P, Pirrone MG, Crich D. Influence of substitution at the 5α-Position on the side chain conformation of glucopyranosides. Carbohydr Res 2021; 500:108254. [PMID: 33561715 DOI: 10.1016/j.carres.2021.108254] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Revised: 01/26/2021] [Accepted: 01/27/2021] [Indexed: 10/22/2022]
Abstract
We describe the preparation of methyl 5α-methyl-α-d-glucopyranoside and of 5α-fluoro-β-d-glucopyranose per acetate and the NMR-based conformational analysis of their side chains. Both the 5α-methyl and 5α-fluoro substituents increase the population of the gauche,gauche side chain conformer to the extent that it becomes the predominant conformation. In the 5α-methyl series this is attributed to steric effects, whereas in the 5α-fluoro series the optimization of attractive gauche effects is the more likely reason.
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Affiliation(s)
- Parasuraman Rajasekaran
- Department of Pharmaceutical and Biomedical Sciences, University of Georgia, 250 West Green Street, Athens, GA, 30602, USA; Complex Carbohydrate Research Center, University of Georgia, 315 Riverbend Road, Athens, GA, 30602, USA
| | - Michael G Pirrone
- Department of Pharmaceutical and Biomedical Sciences, University of Georgia, 250 West Green Street, Athens, GA, 30602, USA; Complex Carbohydrate Research Center, University of Georgia, 315 Riverbend Road, Athens, GA, 30602, USA
| | - David Crich
- Department of Pharmaceutical and Biomedical Sciences, University of Georgia, 250 West Green Street, Athens, GA, 30602, USA; Complex Carbohydrate Research Center, University of Georgia, 315 Riverbend Road, Athens, GA, 30602, USA; Department of Chemistry, University of Georgia, 140 Cedar Street, Athens, GA, 30602, USA.
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Xiong J, Xu D. Mechanistic Insights into the Hydrolysis of O-GlcNAcylation Catalyzed by Human O-GlcNAcase. J Phys Chem B 2020; 124:9310-9322. [PMID: 32970432 DOI: 10.1021/acs.jpcb.0c05755] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
O-GlcNAc glycosylation occurs on specific serine/threonine residues of intracellular proteins, which is widely related to various diseases, including type II diabetes, cancer, and Alzheimer's disease. Human O-GlcNAcase (hOGA) is responsible for the removal of O-GlcNAc modification and thus serves as the main target for inhibitor design. In this work, we systematically investigated the mechanism catalyzed by hOGA using the quantum mechanical/molecular mechanical method. Based on calculated free energy profiles, two essential steps named cyclization (Cyc) step and ring opening step are required to generate the final hemiacetal product. The Cyc of the 2-acetamido group, the rate-limiting step, leads to the generation of the intermediate of a bicyclic oxazolinium ion (EI1). Next, the oxazoline ring could be broken via the nucleophilic attack of a water molecule at the C1 position, which generates the final product. Along with this, our simulations clearly suggest the existence of an oxazoline intermediate (EI2), which is produced via proton transfer (PT) from the 2-acetamido group (EI1) to D174. This PT step features a reversible process with a low energy barrier, which could be attributed to a low barrier hydrogen bond between the donor and acceptor. The stabilizing effect of the low barrier hydrogen bond on EI1 is proposed to be very important for accelerating the overall reaction. In fact, the site-directed mutagenesis simulations of D174A and D175A strongly indicate that the catalytic residues mainly affect the observed reaction rate by affecting the stability of the intermediate.
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Affiliation(s)
- Jing Xiong
- School of Pharmacy, Chengdu Medical College, Chengdu, Sichuan 610500, P. R. China
| | - Dingguo Xu
- MOE Key Laboratory of Green Chemistry & Technology, College of Chemistry, Sichuan University, Chengdu, Sichuan 610064, P. R. China
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Domain sliding of two Staphylococcus aureus N-acetylglucosaminidases enables their substrate-binding prior to its catalysis. Commun Biol 2020; 3:178. [PMID: 32313083 PMCID: PMC7170848 DOI: 10.1038/s42003-020-0911-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Accepted: 03/23/2020] [Indexed: 12/22/2022] Open
Abstract
To achieve productive binding, enzymes and substrates must align their geometries to complement each other along an entire substrate binding site, which may require enzyme flexibility. In pursuit of novel drug targets for the human pathogen S. aureus, we studied peptidoglycan N-acetylglucosaminidases, whose structures are composed of two domains forming a V-shaped active site cleft. Combined insights from crystal structures supported by site-directed mutagenesis, modeling, and molecular dynamics enabled us to elucidate the substrate binding mechanism of SagB and AtlA-gl. This mechanism requires domain sliding from the open form observed in their crystal structures, leading to polysaccharide substrate binding in the closed form, which can enzymatically process the bound substrate. We suggest that these two hydrolases must exhibit unusual extents of flexibility to cleave the rigid structure of a bacterial cell wall.
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Fisher JF, Mobashery S. Constructing and deconstructing the bacterial cell wall. Protein Sci 2020; 29:629-646. [PMID: 31747090 PMCID: PMC7021008 DOI: 10.1002/pro.3737] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Revised: 09/17/2019] [Accepted: 09/18/2019] [Indexed: 12/11/2022]
Abstract
The history of modern medicine cannot be written apart from the history of the antibiotics. Antibiotics are cytotoxic secondary metabolites that are isolated from Nature. The antibacterial antibiotics disproportionately target bacterial protein structure that is distinct from eukaryotic protein structure, notably within the ribosome and within the pathways for bacterial cell-wall biosynthesis (for which there is not a eukaryotic counterpart). This review focuses on a pre-eminent class of antibiotics-the β-lactams, exemplified by the penicillins and cephalosporins-from the perspective of the evolving mechanisms for bacterial resistance. The mechanism of action of the β-lactams is bacterial cell-wall destruction. In the monoderm (single membrane, Gram-positive staining) pathogen Staphylococcus aureus the dominant resistance mechanism is expression of a β-lactam-unreactive transpeptidase enzyme that functions in cell-wall construction. In the diderm (dual membrane, Gram-negative staining) pathogen Pseudomonas aeruginosa a dominant resistance mechanism (among several) is expression of a hydrolytic enzyme that destroys the critical β-lactam ring of the antibiotic. The key sensing mechanism used by P. aeruginosa is monitoring the molecular difference between cell-wall construction and cell-wall deconstruction. In both bacteria, the resistance pathways are manifested only when the bacteria detect the presence of β-lactams. This review summarizes how the β-lactams are sensed and how the resistance mechanisms are manifested, with the expectation that preventing these processes will be critical to future chemotherapeutic control of multidrug resistant bacteria.
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Affiliation(s)
- Jed F. Fisher
- Department of Chemistry and BiochemistryUniversity of Notre DameSouth BendIndiana
| | - Shahriar Mobashery
- Department of Chemistry and BiochemistryUniversity of Notre DameSouth BendIndiana
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Characterization and diversity of the complete set of GH family 3 enzymes from Rhodothermus marinus DSM 4253. Sci Rep 2020; 10:1329. [PMID: 31992772 PMCID: PMC6987092 DOI: 10.1038/s41598-020-58015-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Accepted: 01/07/2020] [Indexed: 11/08/2022] Open
Abstract
The genome of Rhodothermus marinus DSM 4253 encodes six glycoside hydrolases (GH) classified under GH family 3 (GH3): RmBgl3A, RmBgl3B, RmBgl3C, RmXyl3A, RmXyl3B and RmNag3. The biochemical function, modelled 3D-structure, gene cluster and evolutionary relationships of each of these enzymes were studied. The six enzymes were clustered into three major evolutionary lineages of GH3: β-N-acetyl-glucosaminidases, β-1,4-glucosidases/β-xylosidases and macrolide β-glucosidases. The RmNag3 with additional β-lactamase domain clustered with the deepest rooted GH3-lineage of β-N-acetyl-glucosaminidases and was active on acetyl-chitooligosaccharides. RmBgl3B displayed β-1,4-glucosidase activity and was the only representative of the lineage clustered with macrolide β-glucosidases from Actinomycetes. The β-xylosidases, RmXyl3A and RmXyl3B, and the β-glucosidases RmBgl3A and RmBgl3C clustered within the major β-glucosidases/β-xylosidases evolutionary lineage. RmXyl3A and RmXyl3B showed β-xylosidase activity with different specificities for para-nitrophenyl (pNP)-linked substrates and xylooligosaccharides. RmBgl3A displayed β-1,4-glucosidase/β-xylosidase activity while RmBgl3C was active on pNP-β-Glc and β-1,3-1,4-linked glucosyl disaccharides. Putative polysaccharide utilization gene clusters were also investigated for both R. marinus DSM 4253 and DSM 4252T (homolog strain). The analysis showed that in the homolog strain DSM 4252TRmar_1080 (RmXyl3A) and Rmar_1081 (RmXyl3B) are parts of a putative polysaccharide utilization locus (PUL) for xylan utilization.
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Mahasenan KV, Batuecas MT, De Benedetti S, Kim C, Rana N, Lee M, Hesek D, Fisher JF, Sanz-Aparicio J, Hermoso JA, Mobashery S. Catalytic Cycle of Glycoside Hydrolase BglX from Pseudomonas aeruginosa and Its Implications for Biofilm Formation. ACS Chem Biol 2020; 15:189-196. [PMID: 31877028 PMCID: PMC7995829 DOI: 10.1021/acschembio.9b00754] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
BglX is a heretofore uncharacterized periplasmic glycoside hydrolase (GH) of the human pathogen Pseudomonas aeruginosa. X-ray analysis identifies it as a protein homodimer. The two active sites of the homodimer comprise catalytic residues provided by each monomer. This arrangement is seen in <2% of the hydrolases of known structure. In vitro substrate profiling shows BglX is a catalyst for β-(1→2) and β-(1→3) saccharide hydrolysis. Saccharides with β-(1→4) or β-(1→6) bonds, and the β-(1→4) muropeptides from the cell-wall peptidoglycan, are not substrates. Additional structural insights from X-ray analysis (including structures of a mutant enzyme-derived Michaelis complex, two transition-state mimetics, and two enzyme-product complexes) enabled the comprehensive description of BglX catalysis. The half-chair (4H3) conformation of the transition-state oxocarbenium species, the approach of the hydrolytic water molecule to the oxocarbenium species, and the stepwise release of the two reaction products were also visualized. The substrate pattern for BglX aligns with the [β-(1→2)-Glc]x and [β-(1→3)-Glc]x periplasmic osmoregulated periplasmic glucans, and possibly with the Psl exopolysaccharides, of P. aeruginosa. Both polysaccharides are implicated in biofilm formation. Accordingly, we show that inactivation of the bglX gene of P. aeruginosa PAO1 attenuates biofilm formation.
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Affiliation(s)
- Kiran V Mahasenan
- Department of Chemistry and Biochemistry , University of Notre Dame , Notre Dame , Indiana 46556 , United States
| | - María T Batuecas
- Department of Crystallography and Structural Biology , Institute of Physical Chemistry "Rocasolano", CSIC , 28006 Madrid , Spain
| | - Stefania De Benedetti
- Department of Chemistry and Biochemistry , University of Notre Dame , Notre Dame , Indiana 46556 , United States
| | - Choon Kim
- Department of Chemistry and Biochemistry , University of Notre Dame , Notre Dame , Indiana 46556 , United States
| | - Neha Rana
- Department of Chemistry and Biochemistry , University of Notre Dame , Notre Dame , Indiana 46556 , United States
| | - Mijoon Lee
- Department of Chemistry and Biochemistry , University of Notre Dame , Notre Dame , Indiana 46556 , United States
| | - Dusan Hesek
- Department of Chemistry and Biochemistry , University of Notre Dame , Notre Dame , Indiana 46556 , United States
| | - Jed F Fisher
- Department of Chemistry and Biochemistry , University of Notre Dame , Notre Dame , Indiana 46556 , United States
| | - Julia Sanz-Aparicio
- Department of Crystallography and Structural Biology , Institute of Physical Chemistry "Rocasolano", CSIC , 28006 Madrid , Spain
| | - Juan A Hermoso
- Department of Crystallography and Structural Biology , Institute of Physical Chemistry "Rocasolano", CSIC , 28006 Madrid , Spain
| | - Shahriar Mobashery
- Department of Chemistry and Biochemistry , University of Notre Dame , Notre Dame , Indiana 46556 , United States
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Itoh T, Araki T, Nishiyama T, Hibi T, Kimoto H. Structural and functional characterization of a glycoside hydrolase family 3 β-N-acetylglucosaminidase from Paenibacillus sp. str. FPU-7. J Biochem 2019; 166:503-515. [DOI: 10.1093/jb/mvz072] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Accepted: 08/11/2019] [Indexed: 11/14/2022] Open
Abstract
AbstractChitin, a β-1,4-linked homopolysaccharide of N-acetyl-d-glucosamine (GlcNAc), is one of the most abundant biopolymers on Earth. Paenibacillus sp. str. FPU-7 produces several different chitinases and converts chitin into N,N′-diacetylchitobiose ((GlcNAc)2) in the culture medium. However, the mechanism by which the Paenibacillus species imports (GlcNAc)2 into the cytoplasm and divides it into the monomer GlcNAc remains unclear. The gene encoding Paenibacillus β-N-acetyl-d-glucosaminidase (PsNagA) was identified in the Paenibacillus sp. str. FPU-7 genome using an expression cloning system. The deduced amino acid sequence of PsNagA suggests that the enzyme is a part of the glycoside hydrolase family 3 (GH3). Recombinant PsNagA was successfully overexpressed in Escherichia coli and purified to homogeneity. As assessed by gel permeation chromatography, the enzyme exists as a 57-kDa monomer. PsNagA specifically hydrolyses chitin oligosaccharides, (GlcNAc)2–4, 4-nitrophenyl N-acetyl β-d-glucosamine (pNP-GlcNAc) and pNP-(GlcNAc)2–6, but has no detectable activity against 4-nitrophenyl β-d-glucose, 4-nitrophenyl β-d-galactosamine and colloidal chitin. In this study, we present a 1.9 Å crystal structure of PsNagA bound to GlcNAc. The crystal structure reveals structural features related to substrate recognition and the catalytic mechanism of PsNagA. This is the first study on the structural and functional characterization of a GH3 β-N-acetyl-d-glucosaminidase from Paenibacillus sp.
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Affiliation(s)
- Takafumi Itoh
- Department of Bioscience and Biotechnology, Fukui Prefectural University, 4-1-1 Matsuokakenjyoujima, Eiheiji-cho, Yoshida-gun, Fukui 910-1195, Japan
| | - Tomomitsu Araki
- Department of Bioscience and Biotechnology, Fukui Prefectural University, 4-1-1 Matsuokakenjyoujima, Eiheiji-cho, Yoshida-gun, Fukui 910-1195, Japan
| | - Tomohiro Nishiyama
- Department of Bioscience and Biotechnology, Fukui Prefectural University, 4-1-1 Matsuokakenjyoujima, Eiheiji-cho, Yoshida-gun, Fukui 910-1195, Japan
| | - Takao Hibi
- Department of Bioscience and Biotechnology, Fukui Prefectural University, 4-1-1 Matsuokakenjyoujima, Eiheiji-cho, Yoshida-gun, Fukui 910-1195, Japan
| | - Hisashi Kimoto
- Department of Bioscience and Biotechnology, Fukui Prefectural University, 4-1-1 Matsuokakenjyoujima, Eiheiji-cho, Yoshida-gun, Fukui 910-1195, Japan
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19
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A Bacillus pumilus originated β-N-acetylglucosaminidase for chitin combinatory hydrolysis and exploration of its thermostable mechanism. Int J Biol Macromol 2019; 132:1282-1289. [DOI: 10.1016/j.ijbiomac.2019.04.054] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2019] [Revised: 04/08/2019] [Accepted: 04/08/2019] [Indexed: 11/23/2022]
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20
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The hydrolase LpqI primes mycobacterial peptidoglycan recycling. Nat Commun 2019; 10:2647. [PMID: 31201321 PMCID: PMC6572805 DOI: 10.1038/s41467-019-10586-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Accepted: 05/14/2019] [Indexed: 12/26/2022] Open
Abstract
Growth and division by most bacteria requires remodelling and cleavage of their cell wall. A byproduct of this process is the generation of free peptidoglycan (PG) fragments known as muropeptides, which are recycled in many model organisms. Bacteria and hosts can harness the unique nature of muropeptides as a signal for cell wall damage and infection, respectively. Despite this critical role for muropeptides, it has long been thought that pathogenic mycobacteria such as Mycobacterium tuberculosis do not recycle their PG. Herein we show that M. tuberculosis and Mycobacterium bovis BCG are able to recycle components of their PG. We demonstrate that the core mycobacterial gene lpqI, encodes an authentic NagZ β-N-acetylglucosaminidase and that it is essential for PG-derived amino sugar recycling via an unusual pathway. Together these data provide a critical first step in understanding how mycobacteria recycle their peptidoglycan. Bacterial growth and division require remodelling of the cell wall, which generates free peptidoglycan fragments. Here, Moynihan et al. show that Mycobacterium tuberculosis can recycle components of their peptidoglycan, and characterise a crucial enzyme required for this process.
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21
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Discovery of processive catalysis by an exo-hydrolase with a pocket-shaped active site. Nat Commun 2019; 10:2222. [PMID: 31110237 PMCID: PMC6527550 DOI: 10.1038/s41467-019-09691-z] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Accepted: 03/22/2019] [Indexed: 11/08/2022] Open
Abstract
Substrates associate and products dissociate from enzyme catalytic sites rapidly, which hampers investigations of their trajectories. The high-resolution structure of the native Hordeum exo-hydrolase HvExoI isolated from seedlings reveals that non-covalently trapped glucose forms a stable enzyme-product complex. Here, we report that the alkyl β-d-glucoside and methyl 6-thio-β-gentiobioside substrate analogues perfused in crystalline HvExoI bind across the catalytic site after they displace glucose, while methyl 2-thio-β-sophoroside attaches nearby. Structural analyses and multi-scale molecular modelling of nanoscale reactant movements in HvExoI reveal that upon productive binding of incoming substrates, the glucose product modifies its binding patterns and evokes the formation of a transient lateral cavity, which serves as a conduit for glucose departure to allow for the next catalytic round. This path enables substrate-product assisted processive catalysis through multiple hydrolytic events without HvExoI losing contact with oligo- or polymeric substrates. We anticipate that such enzyme plasticity could be prevalent among exo-hydrolases. Enzyme substrates and products often diffuse too rapidly to assess the catalytic implications of these movements. Here, the authors characterise the structural basis of product and substrate diffusion for an exo-hydrolase and discover a substrate-product assisted processive catalytic mechanism.
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Vermassen A, Leroy S, Talon R, Provot C, Popowska M, Desvaux M. Cell Wall Hydrolases in Bacteria: Insight on the Diversity of Cell Wall Amidases, Glycosidases and Peptidases Toward Peptidoglycan. Front Microbiol 2019; 10:331. [PMID: 30873139 PMCID: PMC6403190 DOI: 10.3389/fmicb.2019.00331] [Citation(s) in RCA: 179] [Impact Index Per Article: 35.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Accepted: 02/08/2019] [Indexed: 11/13/2022] Open
Abstract
The cell wall (CW) of bacteria is an intricate arrangement of macromolecules, at least constituted of peptidoglycan (PG) but also of (lipo)teichoic acids, various polysaccharides, polyglutamate and/or proteins. During bacterial growth and division, there is a constant balance between CW degradation and biosynthesis. The CW is remodeled by bacterial hydrolases, whose activities are carefully regulated to maintain cell integrity or lead to bacterial death. Each cell wall hydrolase (CWH) has a specific role regarding the PG: (i) cell wall amidase (CWA) cleaves the amide bond between N-acetylmuramic acid and L-alanine residue at the N-terminal of the stem peptide, (ii) cell wall glycosidase (CWG) catalyses the hydrolysis of the glycosidic linkages, whereas (iii) cell wall peptidase (CWP) cleaves amide bonds between amino acids within the PG chain. After an exhaustive overview of all known conserved catalytic domains responsible for CWA, CWG, and CWP activities, this review stresses that the CWHs frequently display a modular architecture combining multiple and/or different catalytic domains, including some lytic transglycosylases as well as CW binding domains. From there, direct physiological and collateral roles of CWHs in bacterial cells are further discussed.
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Affiliation(s)
- Aurore Vermassen
- Université Clermont Auvergne, INRA, MEDiS, Clermont-Ferrand, France
| | - Sabine Leroy
- Université Clermont Auvergne, INRA, MEDiS, Clermont-Ferrand, France
| | - Régine Talon
- Université Clermont Auvergne, INRA, MEDiS, Clermont-Ferrand, France
| | | | - Magdalena Popowska
- Department of Applied Microbiology, Faculty of Biology, Institute of Microbiology, University of Warsaw, Warsaw, Poland
| | - Mickaël Desvaux
- Université Clermont Auvergne, INRA, MEDiS, Clermont-Ferrand, France
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Jiang S, Jiang H, Zhou Y, Jiang S, Zhang G. High-level expression of β-N-Acetylglucosaminidase BsNagZ in Pichia pastoris to obtain GlcNAc. Bioprocess Biosyst Eng 2019; 42:611-619. [DOI: 10.1007/s00449-018-02067-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2018] [Accepted: 12/21/2018] [Indexed: 01/11/2023]
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Structural enzymology reveals the molecular basis of substrate regiospecificity and processivity of an exemplar bacterial glycoside hydrolase family 74 endo-xyloglucanase. Biochem J 2018; 475:3963-3978. [PMID: 30463871 DOI: 10.1042/bcj20180763] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Revised: 11/18/2018] [Accepted: 11/21/2018] [Indexed: 12/21/2022]
Abstract
Paenibacillus odorifer produces a single multimodular enzyme containing a glycoside hydrolase (GH) family 74 module (AIQ73809). Recombinant production and characterization of the GH74 module (PoGH74cat) revealed a highly specific, processive endo-xyloglucanase that can hydrolyze the polysaccharide backbone at both branched and unbranched positions. X-ray crystal structures obtained for the free enzyme and oligosaccharide complexes evidenced an extensive hydrophobic binding platform - the first in GH74 extending from subsites -4 to +6 - and unique mobile active-site loops. Site-directed mutagenesis revealed that glycine-476 was uniquely responsible for the promiscuous backbone-cleaving activity of PoGH74cat; replacement with tyrosine, which is conserved in many GH74 members, resulted in exclusive hydrolysis at unbranched glucose units. Likewise, systematic replacement of the hydrophobic platform residues constituting the positive subsites indicated their relative contributions to the processive mode of action. Specifically, W347 (+3 subsite) and W348 (+5 subsite) are essential for processivity, while W406 (+2 subsite) and Y372 (+6 subsite) are not strictly essential, but aid processivity.
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25
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Ho LA, Winogrodzki JL, Debowski AW, Madden Z, Vocadlo DJ, Mark BL, Stubbs KA. A mechanism-based GlcNAc-inspired cyclophellitol inactivator of the peptidoglycan recycling enzyme NagZ reverses resistance to β-lactams in Pseudomonas aeruginosa. Chem Commun (Camb) 2018; 54:10630-10633. [PMID: 30178799 DOI: 10.1039/c8cc05281f] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The development of a potent mechanism-based inactivator of NagZ, an enzyme critical to the production of inducible AmpC β-lactamase in Gram-negative bacteria, is presented. This inactivator significantly reduces MIC values for important β-lactams against a clinically relevant strain of Pseudomonas aeruginosa.
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Affiliation(s)
- Louisa A Ho
- School of Molecular Sciences, University of Western Australia, Crawley, WA 6009, Australia.
| | - Judith L Winogrodzki
- Department of Microbiology, University of Manitoba, Winnipeg, Manitoba R3T2N2, Canada.
| | - Aleksandra W Debowski
- School of Molecular Sciences, University of Western Australia, Crawley, WA 6009, Australia. and School of Biomedical Sciences, University of Western Australia, Crawley, WA 6009, Australia
| | - Zarina Madden
- Department of Chemistry, Simon Fraser University, Burnaby, BC V5A1S6, Canada
| | - David J Vocadlo
- Department of Chemistry, Simon Fraser University, Burnaby, BC V5A1S6, Canada
| | - Brian L Mark
- Department of Microbiology, University of Manitoba, Winnipeg, Manitoba R3T2N2, Canada.
| | - Keith A Stubbs
- School of Molecular Sciences, University of Western Australia, Crawley, WA 6009, Australia.
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Dik DA, Fisher JF, Mobashery S. Cell-Wall Recycling of the Gram-Negative Bacteria and the Nexus to Antibiotic Resistance. Chem Rev 2018; 118:5952-5984. [PMID: 29847102 PMCID: PMC6855303 DOI: 10.1021/acs.chemrev.8b00277] [Citation(s) in RCA: 121] [Impact Index Per Article: 20.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The importance of the cell wall to the viability of the bacterium is underscored by the breadth of antibiotic structures that act by blocking key enzymes that are tasked with cell-wall creation, preservation, and regulation. The interplay between cell-wall integrity, and the summoning forth of resistance mechanisms to deactivate cell-wall-targeting antibiotics, involves exquisite orchestration among cell-wall synthesis and remodeling and the detection of and response to the antibiotics through modulation of gene regulation by specific effectors. Given the profound importance of antibiotics to the practice of medicine, the assertion that understanding this interplay is among the most fundamentally important questions in bacterial physiology is credible. The enigmatic regulation of the expression of the AmpC β-lactamase, a clinically significant and highly regulated resistance response of certain Gram-negative bacteria to the β-lactam antibiotics, is the exemplar of this challenge. This review gives a current perspective to this compelling, and still not fully solved, 35-year enigma.
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Affiliation(s)
- David A. Dik
- Department of Chemistry and Biochemistry, McCourtney Hall, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Jed F. Fisher
- Department of Chemistry and Biochemistry, McCourtney Hall, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Shahriar Mobashery
- Department of Chemistry and Biochemistry, McCourtney Hall, University of Notre Dame, Notre Dame, Indiana 46556, United States
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27
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Bouquet J, King DT, Vadlamani G, Benzie GR, Iorga B, Ide D, Adachi I, Kato A, Vocadlo DJ, Mark BL, Blériot Y, Désiré J. Selective trihydroxylated azepane inhibitors of NagZ, a glycosidase involved in Pseudomonas aeruginosa resistance to β-lactam antibiotics. Org Biomol Chem 2018; 15:4609-4619. [PMID: 28513749 DOI: 10.1039/c7ob00838d] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The synthesis of a series of d-gluco-like configured 4,5,6-trihydroxyazepanes bearing a triazole, a sulfonamide or a fluorinated acetamide moiety at C-3 is described. These synthetic derivatives have been tested for their ability to selectively inhibit the muropeptide recycling glucosaminidase NagZ and to thereby increase sensitivity of Pseudomonas aeruginosa to β-lactams, a pathway with substantial therapeutic potential. While introduction of triazole and sulfamide groups failed to lead to glucosaminidase inhibitors, the NHCOCF3 analog proved to be a selective inhibitor of NagZ over other glucosaminidases including human O-GlcNAcase and lysosomal hexosaminidases HexA and B.
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Affiliation(s)
- J Bouquet
- Equipe Synthèse Organique, Groupe Glycochimie, IC2MP, UMR CNRS 7285, Université de Poitiers, 4 rue Michel Brunet, 86073 Poitiers cedex 09, France.
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28
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Mechanism of the Escherichia coli MltE lytic transglycosylase, the cell-wall-penetrating enzyme for Type VI secretion system assembly. Sci Rep 2018. [PMID: 29515200 PMCID: PMC5841429 DOI: 10.1038/s41598-018-22527-y] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Lytic transglycosylases (LTs) catalyze the non-hydrolytic cleavage of the bacterial cell wall by an intramolecular transacetalization reaction. This reaction is critically and broadly important in modifications of the bacterial cell wall in the course of its biosynthesis, recycling, manifestation of virulence, insertion of structural entities such as the flagellum and the pili, among others. The first QM/MM analysis of the mechanism of reaction of an LT, that for the Escherichia coli MltE, is undertaken. The study reveals a conformational itinerary consistent with an oxocarbenium-like transition state, characterized by a pivotal role for the active-site glutamic acid in proton transfer. Notably, an oxazolinium intermediate, as a potential intermediate, is absent. Rather, substrate-assisted catalysis is observed through a favorable dipole provided by the N-acetyl carbonyl group of MurNAc saccharide. This interaction stabilizes the incipient positive charge development in the transition state. This mechanism coincides with near-synchronous acetal cleavage and acetal formation.
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Macdonald SS, Patel A, Larmour VLC, Morgan-Lang C, Hallam SJ, Mark BL, Withers SG. Structural and mechanistic analysis of a β-glycoside phosphorylase identified by screening a metagenomic library. J Biol Chem 2018; 293:3451-3467. [PMID: 29317495 DOI: 10.1074/jbc.ra117.000948] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2017] [Revised: 01/04/2018] [Indexed: 11/06/2022] Open
Abstract
Glycoside phosphorylases have considerable potential as catalysts for the assembly of useful glycans for products ranging from functional foods and prebiotics to novel materials. However, the substrate diversity of currently identified phosphorylases is relatively small, limiting their practical applications. To address this limitation, we developed a high-throughput screening approach using the activated substrate 2,4-dinitrophenyl β-d-glucoside (DNPGlc) and inorganic phosphate for identifying glycoside phosphorylase activity and used it to screen a large insert metagenomic library. The initial screen, based on release of 2,4-dinitrophenyl from DNPGlc in the presence of phosphate, identified the gene bglP, encoding a retaining β-glycoside phosphorylase from the CAZy GH3 family. Kinetic and mechanistic analysis of the gene product, BglP, confirmed a double displacement ping-pong mechanism involving a covalent glycosyl-enzyme intermediate. X-ray crystallographic analysis provided insights into the phosphate-binding mode and identified a key glutamine residue in the active site important for substrate recognition. Substituting this glutamine for a serine swapped the substrate specificity from glucoside to N-acetylglucosaminide. In summary, we present a high-throughput screening approach for identifying β-glycoside phosphorylases, which was robust, simple to implement, and useful in identifying active clones within a metagenomics library. Implementation of this screen enabled discovery of a new glycoside phosphorylase class and has paved the way to devising simple ways in which enzyme specificity can be encoded and swapped, which has implications for biotechnological applications.
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Affiliation(s)
- Spencer S Macdonald
- From the Departments of Chemistry and Biochemistry and.,the Genome Science and Technology Program.,ECOSCOPE Training Program, University of British Columbia, Vancouver, British Columbia V6T 1Z3, and
| | - Ankoor Patel
- the Department of Microbiology, University of Manitoba, Winnipeg, Manitoba R3T 2N2
| | - Veronica L C Larmour
- the Department of Microbiology, University of Manitoba, Winnipeg, Manitoba R3T 2N2
| | | | - Steven J Hallam
- the Genome Science and Technology Program.,ECOSCOPE Training Program, University of British Columbia, Vancouver, British Columbia V6T 1Z3, and.,Graduate Program in Bioinformatics, and.,the Department of Microbiology and Immunology and.,Peter Wall Institute for Advanced Studies, University of British Columbia, Vancouver, British Columbia V6T 1Z1
| | - Brian L Mark
- the Department of Microbiology, University of Manitoba, Winnipeg, Manitoba R3T 2N2
| | - Stephen G Withers
- From the Departments of Chemistry and Biochemistry and .,the Genome Science and Technology Program.,ECOSCOPE Training Program, University of British Columbia, Vancouver, British Columbia V6T 1Z3, and.,Michael Smith Laboratories, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
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30
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Wang P, Bi S, Wu F, Xu P, Shen X, Zhao Q. Differentially expressed genes in the head of the 2nd instar pre-molting larvae of the nm2 mutant of the silkworm, Bombyx mori. PLoS One 2017; 12:e0180160. [PMID: 28727825 PMCID: PMC5519023 DOI: 10.1371/journal.pone.0180160] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2017] [Accepted: 06/10/2017] [Indexed: 12/20/2022] Open
Abstract
Molting is an important physiological process in the larval stage of Bombyx mori and is controlled by various hormones and peptides. The silkworm mutant that exhibits the phenotype of non-molting in the 2nd instar (nm2) is incapable of molting in the 2nd instar and dies after seven or more days. The ecdysone titer in the nm2 mutant is lower than that in the wildtype, and the mutant can be rescued by feeding with 20E and cholesterol. The results of positional cloning indicated that structural alteration of BmCPG10 is responsible for the phenotype of the nm2 mutant. To explore the possible relationship between BmCPG10 and the ecdysone titer as well as the genes affected by BmCPG10, digital gene expression (DGE) profile analysis was conducted in the nm2 mutant, with the wildtype strain C603 serving as the control. The results revealed 1727 differentially expressed genes, among which 651 genes were upregulated and 1076 were downregulated in nm2. BLASTGO analysis showed that these differentially expressed genes were involved in various biological processes, cellular components and molecular functions. KEGG analysis indicated an enrichment of these differentially expressed genes in 240 pathways, including metabolic pathways, pancreatic secretion, protein digestion and absorption, fat digestion and absorption and glycerolipid metabolism. To verify the accuracy of the DGE results, quantitative reverse transcription PCR (qRT-PCR) was performed, focusing on key genes in several related pathways, and the results were highly consistent with the DGE results. Our findings indicated significant differences in cuticular protein genes, ecdysone biosynthesis genes and ecdysone-related nuclear receptors genes, but no significant difference in juvenile hormone and chitin biosynthesis genes was detected. Our research findings lay the foundation for further research on the formation mechanism of the nm2 mutant.
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Affiliation(s)
- Pingyang Wang
- School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang Jiangsu, China
- The Sericulture Research Institute, Chinese Academy of Agricultural Sciences, Zhenjiang Jiangsu, China
| | - Simin Bi
- School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang Jiangsu, China
- The Sericulture Research Institute, Chinese Academy of Agricultural Sciences, Zhenjiang Jiangsu, China
| | - Fan Wu
- Industrial Crops Institute, Hubei Academy of Agricultural Sciences, Wuhan, China
| | - Pingzhen Xu
- School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang Jiangsu, China
- The Sericulture Research Institute, Chinese Academy of Agricultural Sciences, Zhenjiang Jiangsu, China
| | - Xingjia Shen
- School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang Jiangsu, China
- The Sericulture Research Institute, Chinese Academy of Agricultural Sciences, Zhenjiang Jiangsu, China
| | - Qiaoling Zhao
- School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang Jiangsu, China
- The Sericulture Research Institute, Chinese Academy of Agricultural Sciences, Zhenjiang Jiangsu, China
- * E-mail:
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31
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A Novel Multifunctional β-N-Acetylhexosaminidase Revealed through Metagenomics of an Oil-Spilled Mangrove. Bioengineering (Basel) 2017; 4:bioengineering4030062. [PMID: 28952541 PMCID: PMC5615308 DOI: 10.3390/bioengineering4030062] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Revised: 06/25/2017] [Accepted: 07/06/2017] [Indexed: 11/22/2022] Open
Abstract
The use of culture-independent approaches, such as metagenomics, provides complementary access to environmental microbial diversity. Mangrove environments represent a highly complex system with plenty of opportunities for finding singular functions. In this study we performed a functional screening of fosmid libraries obtained from an oil contaminated mangrove site, with the purpose of identifying clones expressing hydrolytic activities. A novel gene coding for a β-N-acetylhexosaminidase with 355 amino acids and 43KDa was retrieved and characterized. The translated sequence showed only 38% similarity to a β-N-acetylhexosaminidase gene in the genome of Veillonella sp. CAG:933, suggesting that it might constitute a novel enzyme. The enzyme was expressed, purified, and characterized for its enzymatic activity on carboxymethyl cellulose, p-Nitrophenyl-2acetamide-2deoxy-β-d-glucopyranoside, p-Nitrophenyl-2acetamide-2deoxy-β-d-galactopyranoside, and 4-Nitrophenyl β-d-glucopyranoside, presenting β-N-acetylglucosaminidase, β-glucosidase, and β-1,4-endoglucanase activities. The enzyme showed optimum activity at 30 °C and pH 5.5. The characterization of the putative novel β-N-acetylglucosaminidase enzyme reflects similarities to characteristics of the environment explored, which differs from milder conditions environments. This work exemplifies the application of cultivation-independent molecular techniques to the mangrove microbiome for obtaining a novel biotechnological product.
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Ezeilo UR, Zakaria II, Huyop F, Wahab RA. Enzymatic breakdown of lignocellulosic biomass: the role of glycosyl hydrolases and lytic polysaccharide monooxygenases. BIOTECHNOL BIOTEC EQ 2017. [DOI: 10.1080/13102818.2017.1330124] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
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Acebrón I, Mahasenan KV, De Benedetti S, Lee M, Artola-Recolons C, Hesek D, Wang H, Hermoso JA, Mobashery S. Catalytic Cycle of the N-Acetylglucosaminidase NagZ from Pseudomonas aeruginosa. J Am Chem Soc 2017; 139:6795-6798. [PMID: 28482153 DOI: 10.1021/jacs.7b01626] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The N-acetylglucosaminidase NagZ of Pseudomonas aeruginosa catalyzes the first cytoplasmic step in recycling of muropeptides, cell-wall-derived natural products. This reaction regulates gene expression for the β-lactam resistance enzyme, β-lactamase. The enzyme catalyzes hydrolysis of N-acetyl-β-d-glucosamine-(1→4)-1,6-anhydro-N-acetyl-β-d-muramyl-peptide (1) to N-acetyl-β-d-glucosamine (2) and 1,6-anhydro-N-acetyl-β-d-muramyl-peptide (3). The structural and functional aspects of catalysis by NagZ were investigated by a total of seven X-ray structures, three computational models based on the X-ray structures, molecular-dynamics simulations and mutagenesis. The structural insights came from the unbound state and complexes of NagZ with the substrate, products and a mimetic of the transient oxocarbenium species, which were prepared by synthesis. The mechanism involves a histidine as acid/base catalyst, which is unique for glycosidases. The turnover process utilizes covalent modification of D244, requiring two transition-state species and is regulated by coordination with a zinc ion. The analysis provides a seamless continuum for the catalytic cycle, incorporating large motions by four loops that surround the active site.
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Affiliation(s)
- Iván Acebrón
- Department of Crystallography and Structural Biology, Institute of Physical Chemistry "Rocasolano", CSIC , 28006 Madrid, Spain
| | - Kiran V Mahasenan
- Department of Chemistry and Biochemistry, University of Notre Dame , Notre Dame, Indiana 46556, United States
| | - Stefania De Benedetti
- Department of Chemistry and Biochemistry, University of Notre Dame , Notre Dame, Indiana 46556, United States
| | - Mijoon Lee
- Department of Chemistry and Biochemistry, University of Notre Dame , Notre Dame, Indiana 46556, United States
| | - Cecilia Artola-Recolons
- Department of Crystallography and Structural Biology, Institute of Physical Chemistry "Rocasolano", CSIC , 28006 Madrid, Spain
| | - Dusan Hesek
- Department of Chemistry and Biochemistry, University of Notre Dame , Notre Dame, Indiana 46556, United States
| | - Huan Wang
- Department of Chemistry and Biochemistry, University of Notre Dame , Notre Dame, Indiana 46556, United States
| | - Juan A Hermoso
- Department of Crystallography and Structural Biology, Institute of Physical Chemistry "Rocasolano", CSIC , 28006 Madrid, Spain
| | - Shahriar Mobashery
- Department of Chemistry and Biochemistry, University of Notre Dame , Notre Dame, Indiana 46556, United States
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Vadlamani G, Stubbs KA, Désiré J, Blériot Y, Vocadlo DJ, Mark BL. Conformational flexibility of the glycosidase NagZ allows it to bind structurally diverse inhibitors to suppress β-lactam antibiotic resistance. Protein Sci 2017; 26:1161-1170. [PMID: 28370529 DOI: 10.1002/pro.3166] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2017] [Revised: 03/22/2017] [Accepted: 03/23/2017] [Indexed: 11/10/2022]
Abstract
NagZ is an N-acetyl-β-d-glucosaminidase that participates in the peptidoglycan (PG) recycling pathway of Gram-negative bacteria by removing N-acetyl-glucosamine (GlcNAc) from PG fragments that have been excised from the cell wall during growth. The 1,6-anhydromuramoyl-peptide products generated by NagZ activate β-lactam resistance in many Gram-negative bacteria by inducing the expression of AmpC β-lactamase. Blocking NagZ activity can thereby suppress β-lactam antibiotic resistance in these bacteria. The NagZ active site is dynamic and it accommodates distortion of the glycan substrate during catalysis using a mobile catalytic loop that carries a histidine residue which serves as the active site general acid/base catalyst. Here, we show that flexibility of this catalytic loop also accommodates structural differences in small molecule inhibitors of NagZ, which could be exploited to improve inhibitor specificity. X-ray structures of NagZ bound to the potent yet non-selective N-acetyl-β-glucosaminidase inhibitor PUGNAc (O-(2-acetamido-2-deoxy-d-glucopyranosylidene) amino-N-phenylcarbamate), and two NagZ-selective inhibitors - EtBuPUG, a PUGNAc derivative bearing a 2-N-ethylbutyryl group, and MM-156, a 3-N-butyryl trihydroxyazepane, revealed that the phenylcarbamate moiety of PUGNAc and EtBuPUG completely displaces the catalytic loop from the NagZ active site to yield a catalytically incompetent form of the enzyme. In contrast, the catalytic loop was found positioned in the catalytically active conformation within the NagZ active site when bound to MM-156, which lacks the phenylcarbamate extension. Displacement of the catalytic loop by PUGNAc and its N-acyl derivative EtBuPUG alters the active site conformation of NagZ, which presents an additional strategy to improve the potency and specificity of NagZ inhibitors.
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Affiliation(s)
- Grishma Vadlamani
- Department of Microbiology, University of Manitoba, Winnipeg, Manitoba, Canada, R3T2N2
| | - Keith A Stubbs
- School of Molecular Sciences, University of Western Australia, Crawley, Western Australia, 6009, Australia
| | - Jérôme Désiré
- IC2MP, UMR CNRS 7285, Équipe "Synthèse Organique" Groupe Glycochimie, Université de Poitiers, 4 rue Michel Brunet, 86073, Poitiers cedex 9, France
| | - Yves Blériot
- IC2MP, UMR CNRS 7285, Équipe "Synthèse Organique" Groupe Glycochimie, Université de Poitiers, 4 rue Michel Brunet, 86073, Poitiers cedex 9, France
| | - David J Vocadlo
- Department of Chemistry, Simon Fraser University, 8888 University Drive, Burnaby, British Columbia, Canada, V5S 1P6
| | - Brian L Mark
- Department of Microbiology, University of Manitoba, Winnipeg, Manitoba, Canada, R3T2N2
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Growth on Chitin Impacts the Transcriptome and Metabolite Profiles of Antibiotic-Producing Vibrio coralliilyticus S2052 and Photobacterium galatheae S2753. mSystems 2017; 2:mSystems00141-16. [PMID: 28066819 PMCID: PMC5209532 DOI: 10.1128/msystems.00141-16] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2016] [Accepted: 11/30/2016] [Indexed: 11/20/2022] Open
Abstract
The bacterial family Vibrionaceae (vibrios) is considered a major player in the degradation of chitin, the most abundant polymer in the marine environment; however, the majority of studies on the topic have focused on a small number of Vibrio species. In this study, we analyzed the genomes of two vibrios to assess their genetic potential for the degradation of chitin. We then used transcriptomics and metabolomics to demonstrate that chitin strongly affects these vibrios at both the transcriptional and metabolic levels. We observed a strong increase in production of secondary metabolites, suggesting an ecological role for these molecules during chitin colonization in the marine environment. Members of the Vibrionaceae family are often associated with chitin-containing organisms, and they are thought to play a major role in chitin degradation. The purpose of the present study was to determine how chitin affects the transcriptome and metabolome of two bioactive Vibrionaceae strains, Vibrio coralliilyticus and Photobacterium galatheae. We focused on chitin degradation genes and secondary metabolites based on the assumption that these molecules in nature confer an advantage to the producer. Growth on chitin caused upregulation of genes related to chitin metabolism and of genes potentially involved in host colonization and/or infection. The expression of genes involved in secondary metabolism was also significantly affected by growth on chitin, in one case being 34-fold upregulated. This was reflected in the metabolome, where the antibiotics andrimid and holomycin were produced in larger amounts on chitin. Other polyketide synthase/ nonribosomal peptide synthetase (PKS-NRPS) clusters in P. galatheae were also strongly upregulated on chitin. Collectively, this suggests that both V. coralliilyticus and P. galatheae have a specific lifestyle for growth on chitin and that their secondary metabolites likely play a crucial role during chitin colonization. IMPORTANCE The bacterial family Vibrionaceae (vibrios) is considered a major player in the degradation of chitin, the most abundant polymer in the marine environment; however, the majority of studies on the topic have focused on a small number of Vibrio species. In this study, we analyzed the genomes of two vibrios to assess their genetic potential for the degradation of chitin. We then used transcriptomics and metabolomics to demonstrate that chitin strongly affects these vibrios at both the transcriptional and metabolic levels. We observed a strong increase in production of secondary metabolites, suggesting an ecological role for these molecules during chitin colonization in the marine environment.
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Su C, Lu Y, Liu H. N-acetylglucosamine sensing by a GCN5-related N-acetyltransferase induces transcription via chromatin histone acetylation in fungi. Nat Commun 2016; 7:12916. [PMID: 27694804 PMCID: PMC5063960 DOI: 10.1038/ncomms12916] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2015] [Accepted: 08/16/2016] [Indexed: 12/11/2022] Open
Abstract
N-acetylglucosamine (GlcNAc) exists ubiquitously as a component of the surface on a wide range of cells, from bacteria to humans. Many fungi are able to utilize environmental GlcNAc to support growth and induce cellular development, a property important for their survival in various host niches. However, how the GlcNAc signal is sensed and subsequently transduced is largely unknown. Here, we identify a gene that is essential for GlcNAc signalling (NGS1) in Candida albicans, a commensal and pathogenic yeast of humans. Ngs1 can bind GlcNAc through the N-terminal β-N-acetylglucosaminidase homology domain. This binding activates N-acetyltransferase activity in the C-terminal GCN5-related N-acetyltransferase domain, which is required for GlcNAc-induced promoter histone acetylation and transcription. Ngs1 is targeted to the promoters of GlcNAc-inducible genes constitutively by the transcription factor Rep1. Ngs1 is conserved in diverse fungi that have GlcNAc catabolic genes. Thus, fungi use Ngs1 as a GlcNAc-sensor and transducer for GlcNAc-induced transcription. Many fungi are able to metabolise environmental N-acetylglucosamine, however the mechanism by which this molecule is sensed is unclear. Su and Lu et al. show that Candida albicans NGS1 fulfils this function by mediating N-acetylglucosamine-dependent histone acetylation at target genes.
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Affiliation(s)
- Chang Su
- Department of Biological Chemistry, University of California, Irvine, California 92697, USA
| | - Yang Lu
- Department of Biological Chemistry, University of California, Irvine, California 92697, USA
| | - Haoping Liu
- Department of Biological Chemistry, University of California, Irvine, California 92697, USA
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Ramírez-Escudero M, Del Pozo MV, Marín-Navarro J, González B, Golyshin PN, Polaina J, Ferrer M, Sanz-Aparicio J. Structural and Functional Characterization of a Ruminal β-Glycosidase Defines a Novel Subfamily of Glycoside Hydrolase Family 3 with Permuted Domain Topology. J Biol Chem 2016; 291:24200-24214. [PMID: 27679487 PMCID: PMC5104943 DOI: 10.1074/jbc.m116.747527] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2016] [Revised: 09/16/2016] [Indexed: 01/01/2023] Open
Abstract
Metagenomics has opened up a vast pool of genes for putative, yet uncharacterized, enzymes. It widens our knowledge on the enzyme diversity world and discloses new families for which a clear classification is still needed, as is exemplified by glycoside hydrolase family-3 (GH3) proteins. Herein, we describe a GH3 enzyme (GlyA1) from resident microbial communities in strained ruminal fluid. The enzyme is a β-glucosidase/β-xylosidase that also shows β-galactosidase, β-fucosidase, α-arabinofuranosidase, and α-arabinopyranosidase activities. Short cello- and xylo-oligosaccharides, sophorose and gentibiose, are among the preferred substrates, with the large polysaccharide lichenan also being hydrolyzed by GlyA1. The determination of the crystal structure of the enzyme in combination with deletion and site-directed mutagenesis allowed identification of its unusual domain composition and the active site architecture. Complexes of GlyA1 with glucose, galactose, and xylose allowed picturing the catalytic pocket and illustrated the molecular basis of the substrate specificity. A hydrophobic platform defined by residues Trp-711 and Trp-106, located in a highly mobile loop, appears able to allocate differently β-linked bioses. GlyA1 includes an additional C-terminal domain previously unobserved in GH3 members, but crystallization of the full-length enzyme was unsuccessful. Therefore, small angle x-ray experiments have been performed to investigate the molecular flexibility and overall putative shape. This study provided evidence that GlyA1 defines a new subfamily of GH3 proteins with a novel permuted domain topology. Phylogenetic analysis indicates that this topology is associated with microbes inhabiting the digestive tracts of ruminants and other animals, feeding on chemically diverse plant polymeric materials.
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Affiliation(s)
- Mercedes Ramírez-Escudero
- From the Department of Crystallography and Structural Biology, Institute of Physical-Chemistry "Rocasolano," Consejo Superior de Investigaciones Científicas, Serrano 119, 28006 Madrid, Spain
| | - Mercedes V Del Pozo
- the Institute of Catalysis and Petrochemistry, Consejo Superior de Investigaciones Científicas, Marie Curie 2, Cantoblanco, 28049 Madrid, Spain
| | - Julia Marín-Navarro
- the Institute of Agrochemistry and Food Technology, Consejo Superior de Investigaciones Científicas, Carrer Catedràtic Agustín Escardino Benlloch 7, 46980 Paterna, Valencia, Spain
| | - Beatriz González
- From the Department of Crystallography and Structural Biology, Institute of Physical-Chemistry "Rocasolano," Consejo Superior de Investigaciones Científicas, Serrano 119, 28006 Madrid, Spain
| | - Peter N Golyshin
- the School of Biological Sciences, Bangor University, LL57 2UW Gwynedd, United Kingdom, and.,the Immanuel Kant Baltic Federal University, 236040 Kaliningrad, Russia
| | - Julio Polaina
- the Institute of Agrochemistry and Food Technology, Consejo Superior de Investigaciones Científicas, Carrer Catedràtic Agustín Escardino Benlloch 7, 46980 Paterna, Valencia, Spain
| | - Manuel Ferrer
- the Institute of Catalysis and Petrochemistry, Consejo Superior de Investigaciones Científicas, Marie Curie 2, Cantoblanco, 28049 Madrid, Spain,
| | - Julia Sanz-Aparicio
- From the Department of Crystallography and Structural Biology, Institute of Physical-Chemistry "Rocasolano," Consejo Superior de Investigaciones Científicas, Serrano 119, 28006 Madrid, Spain,
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Ducatti DRB, Carroll MA, Jakeman DL. On the phosphorylase activity of GH3 enzymes: A β-N-acetylglucosaminidase from Herbaspirillum seropedicae SmR1 and a glucosidase from Saccharopolyspora erythraea. Carbohydr Res 2016; 435:106-112. [PMID: 27744113 DOI: 10.1016/j.carres.2016.09.015] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Revised: 09/21/2016] [Accepted: 09/21/2016] [Indexed: 10/21/2022]
Abstract
A phosphorolytic activity has been reported for beta-N-acetylglucosaminidases from glycoside hydrolase family 3 (GH3) giving an interesting explanation for an unusual histidine as catalytic acid/base residue and suggesting that members from this family may be phosphorylases [J. Biol. Chem. 2015, 290, 4887]. Here, we describe the characterization of Hsero1941, a GH3 beta-N-acetylglucosaminidase from the endophytic nitrogen-fixing bacterium Herbaspirillum seropedicae SmR1. The enzyme has significantly higher activity against pNP-beta-D-GlcNAcp (Km = 0.24 mM, kcat = 1.2 s-1, kcat/Km = 5.0 mM-1s-1) than pNP-beta-D-Glcp (Km = 33 mM, kcat = 3.3 × 10-3 s-1, kcat/Km = 9 × 10-4 mM-1s-1). The presence of phosphate failed to significantly modify the kinetic parameters of the reaction. The enzyme showed a broad aglycone site specificity, being able to hydrolyze sugar phosphates beta-D-GlcNAc 1P and beta-D-Glc 1P, albeit at a fraction of the rate of hydrolysis of aryl glycosides. GH3 beta-glucosidase EryBI, that does not have a histidine as the general acid/base residue, also hydrolyzed beta-D-Glc 1P, at comparable rates to Hsero1941. These data indicate that Hsero1941 functions primarily as a hydrolase and that phosphorolytic activity is likely adventitious. The prevalence of histidine as a general acid/base residue is not predictive, nor correlative, with GH3 beta-N-acetylglucosaminidases having phosphorolytic activity.
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Affiliation(s)
- Diogo R B Ducatti
- College of Pharmacy, Dalhousie University, 5968 College Street, P.O. Box 15000, Halifax, Nova Scotia B3H 4R2, Canada; Departamento de Bioquímica e Biologia Molecular, Universidade Federal do Paraná, Centro Politécnico, CEP 81-531-990, P.O. Box 19046, Curitiba, Paraná, Brazil
| | - Madison A Carroll
- Department of Chemistry, Dalhousie University, 6274 Coburg Road, P.O. Box 15000, Halifax, Nova Scotia B3H 4R2, Canada
| | - David L Jakeman
- College of Pharmacy, Dalhousie University, 5968 College Street, P.O. Box 15000, Halifax, Nova Scotia B3H 4R2, Canada; Department of Chemistry, Dalhousie University, 6274 Coburg Road, P.O. Box 15000, Halifax, Nova Scotia B3H 4R2, Canada.
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Gudmundsson M, Hansson H, Karkehabadi S, Larsson A, Stals I, Kim S, Sunux S, Fujdala M, Larenas E, Kaper T, Sandgren M. Structural and functional studies of the glycoside hydrolase family 3 β-glucosidase Cel3A from the moderately thermophilic fungus Rasamsonia emersonii. ACTA CRYSTALLOGRAPHICA SECTION D-STRUCTURAL BIOLOGY 2016; 72:860-70. [PMID: 27377383 PMCID: PMC4932919 DOI: 10.1107/s2059798316008482] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/26/2016] [Accepted: 05/25/2016] [Indexed: 12/16/2022]
Abstract
Cel3A from the thermophilic fungus R. emersonii has proven to be more efficient in the hydrolysis of β-glycosidic linkages than Cel3A from H. jecorina. The filamentous fungus Hypocrea jecorina produces a number of cellulases and hemicellulases that act in a concerted fashion on biomass and degrade it into monomeric or oligomeric sugars. β-Glucosidases are involved in the last step of the degradation of cellulosic biomass and hydrolyse the β-glycosidic linkage between two adjacent molecules in dimers and oligomers of glucose. In this study, it is shown that substituting the β-glucosidase from H. jecorina (HjCel3A) with the β-glucosidase Cel3A from the thermophilic fungus Rasamsonia emersonii (ReCel3A) in enzyme mixtures results in increased efficiency in the saccharification of lignocellulosic materials. Biochemical characterization of ReCel3A, heterologously produced in H. jecorina, reveals a preference for disaccharide substrates over longer gluco-oligosaccharides. Crystallographic studies of ReCel3A revealed a highly N-glycosylated three-domain dimeric protein, as has been observed previously for glycoside hydrolase family 3 β-glucosidases. The increased thermal stability and saccharification yield and the superior biochemical characteristics of ReCel3A compared with HjCel3A and mixtures containing HjCel3A make ReCel3A an excellent candidate for addition to enzyme mixtures designed to operate at higher temperatures.
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Affiliation(s)
- Mikael Gudmundsson
- Department of Chemistry and Biotechnology, Swedish University of Agricultural Sciences, Box 7015, 750 07 Uppsala, Sweden
| | - Henrik Hansson
- Department of Chemistry and Biotechnology, Swedish University of Agricultural Sciences, Box 7015, 750 07 Uppsala, Sweden
| | - Saeid Karkehabadi
- Department of Chemistry and Biotechnology, Swedish University of Agricultural Sciences, Box 7015, 750 07 Uppsala, Sweden
| | - Anna Larsson
- Department of Cell and Molecular Biology, Uppsala University, Box 596, 751 24 Uppsala, Sweden
| | - Ingeborg Stals
- Laboratory for Protein Biochemistry and Biomolecular Engineering, Ghent University, Ledeganckstraat 35, B-9000 Ghent, Belgium
| | - Steve Kim
- DuPont Industrial Biosciences, 925 Page Mill Road, Palo Alto, CA 94304, USA
| | - Sergio Sunux
- DuPont Industrial Biosciences, 925 Page Mill Road, Palo Alto, CA 94304, USA
| | - Meredith Fujdala
- DuPont Industrial Biosciences, 925 Page Mill Road, Palo Alto, CA 94304, USA
| | - Edmund Larenas
- DuPont Industrial Biosciences, 925 Page Mill Road, Palo Alto, CA 94304, USA
| | - Thijs Kaper
- DuPont Industrial Biosciences, 925 Page Mill Road, Palo Alto, CA 94304, USA
| | - Mats Sandgren
- Department of Chemistry and Biotechnology, Swedish University of Agricultural Sciences, Box 7015, 750 07 Uppsala, Sweden
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40
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Zhou J, Song Z, Zhang R, Ding L, Wu Q, Li J, Tang X, Xu B, Ding J, Han N, Huang Z. Characterization of a NaCl-tolerant β-N-acetylglucosaminidase from Sphingobacterium sp. HWLB1. Extremophiles 2016; 20:547-57. [DOI: 10.1007/s00792-016-0848-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2016] [Accepted: 05/31/2016] [Indexed: 10/21/2022]
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41
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Nakajima M, Yoshida R, Miyanaga A, Abe K, Takahashi Y, Sugimoto N, Toyoizumi H, Nakai H, Kitaoka M, Taguchi H. Functional and Structural Analysis of a β-Glucosidase Involved in β-1,2-Glucan Metabolism in Listeria innocua. PLoS One 2016; 11:e0148870. [PMID: 26886583 PMCID: PMC4757417 DOI: 10.1371/journal.pone.0148870] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2015] [Accepted: 01/25/2016] [Indexed: 11/18/2022] Open
Abstract
Despite the presence of β-1,2-glucan in nature, few β-1,2-glucan degrading enzymes have been reported to date. Recently, the Lin1839 protein from Listeria innocua was identified as a 1,2-β-oligoglucan phosphorylase. Since the adjacent lin1840 gene in the gene cluster encodes a putative glycoside hydrolase family 3 β-glucosidase, we hypothesized that Lin1840 is also involved in β-1,2-glucan dissimilation. Here we report the functional and structural analysis of Lin1840. A recombinant Lin1840 protein (Lin1840r) showed the highest hydrolytic activity toward sophorose (Glc-β-1,2-Glc) among β-1,2-glucooligosaccharides, suggesting that Lin1840 is a β-glucosidase involved in sophorose degradation. The enzyme also rapidly hydrolyzed laminaribiose (β-1,3), but not cellobiose (β-1,4) or gentiobiose (β-1,6) among β-linked gluco-disaccharides. We determined the crystal structures of Lin1840r in complexes with sophorose and laminaribiose as productive binding forms. In these structures, Arg572 forms many hydrogen bonds with sophorose and laminaribiose at subsite +1, which seems to be a key factor for substrate selectivity. The opposite side of subsite +1 from Arg572 is connected to a large empty space appearing to be subsite +2 for the binding of sophorotriose (Glc-β-1,2-Glc-β-1,2-Glc) in spite of the higher Km value for sophorotriose than that for sophorose. The conformations of sophorose and laminaribiose are almost the same on the Arg572 side but differ on the subsite +2 side that provides no interaction with a substrate. Therefore, Lin1840r is unable to distinguish between sophorose and laminaribiose as substrates. These results provide the first mechanistic insights into β-1,2-glucooligosaccharide recognition by β-glucosidase.
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Affiliation(s)
- Masahiro Nakajima
- Department of Applied Biological Science, Faculty of Science and Technology, Tokyo University of Science, Noda, Chiba, Japan
- * E-mail:
| | - Ryuta Yoshida
- Department of Applied Biological Science, Faculty of Science and Technology, Tokyo University of Science, Noda, Chiba, Japan
| | - Akimasa Miyanaga
- Department of Chemistry, Tokyo Institute of Technology, Meguro-ku, Tokyo, Japan
| | - Koichi Abe
- Department of Applied Biological Science, Faculty of Science and Technology, Tokyo University of Science, Noda, Chiba, Japan
| | - Yuta Takahashi
- Graduate School of Science & Technology, Niigata University, Nishi-ku, Niigata, Japan
| | - Naohisa Sugimoto
- Graduate School of Science & Technology, Niigata University, Nishi-ku, Niigata, Japan
| | - Hiroyuki Toyoizumi
- Department of Applied Biological Science, Faculty of Science and Technology, Tokyo University of Science, Noda, Chiba, Japan
| | - Hiroyuki Nakai
- Graduate School of Science & Technology, Niigata University, Nishi-ku, Niigata, Japan
| | - Motomitsu Kitaoka
- National Food Research Institute, National Agriculture and Food Research Organization, Tsukuba, Ibaraki, Japan
| | - Hayao Taguchi
- Department of Applied Biological Science, Faculty of Science and Technology, Tokyo University of Science, Noda, Chiba, Japan
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42
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Agirre J, Ariza A, Offen WA, Turkenburg JP, Roberts SM, McNicholas S, Harris PV, McBrayer B, Dohnalek J, Cowtan KD, Davies GJ, Wilson KS. Three-dimensional structures of two heavily N-glycosylated Aspergillus sp. family GH3 β-D-glucosidases. Acta Crystallogr D Struct Biol 2016; 72:254-65. [PMID: 26894673 PMCID: PMC4756609 DOI: 10.1107/s2059798315024237] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2015] [Accepted: 12/16/2015] [Indexed: 01/25/2023] Open
Abstract
The industrial conversion of cellulosic plant biomass into useful products such as biofuels is a major societal goal. These technologies harness diverse plant degrading enzymes, classical exo- and endo-acting cellulases and, increasingly, cellulose-active lytic polysaccharide monooxygenases, to deconstruct the recalcitrant β-D-linked polysaccharide. A major drawback with this process is that the exo-acting cellobiohydrolases suffer from severe inhibition from their cellobiose product. β-D-Glucosidases are therefore important for liberating glucose from cellobiose and thereby relieving limiting product inhibition. Here, the three-dimensional structures of two industrially important family GH3 β-D-glucosidases from Aspergillus fumigatus and A. oryzae, solved by molecular replacement and refined at 1.95 Å resolution, are reported. Both enzymes, which share 78% sequence identity, display a three-domain structure with the catalytic domain at the interface, as originally shown for barley β-D-glucan exohydrolase, the first three-dimensional structure solved from glycoside hydrolase family GH3. Both enzymes show extensive N-glycosylation, with only a few external sites being truncated to a single GlcNAc molecule. Those glycans N-linked to the core of the structure are identified purely as high-mannose trees, and establish multiple hydrogen bonds between their sugar components and adjacent protein side chains. The extensive glycans pose special problems for crystallographic refinement, and new techniques and protocols were developed especially for this work. These protocols ensured that all of the D-pyranosides in the glycosylation trees were modelled in the preferred minimum-energy (4)C1 chair conformation and should be of general application to refinements of other crystal structures containing O- or N-glycosylation. The Aspergillus GH3 structures, in light of other recent three-dimensional structures, provide insight into fungal β-D-glucosidases and provide a platform on which to inform and inspire new generations of variant enzymes for industrial application.
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Affiliation(s)
- Jon Agirre
- York Structural Biology Laboratory, Department of Chemistry, The University of York, York YO10 5DD, England
| | - Antonio Ariza
- York Structural Biology Laboratory, Department of Chemistry, The University of York, York YO10 5DD, England
| | - Wendy A. Offen
- York Structural Biology Laboratory, Department of Chemistry, The University of York, York YO10 5DD, England
| | - Johan P. Turkenburg
- York Structural Biology Laboratory, Department of Chemistry, The University of York, York YO10 5DD, England
| | - Shirley M. Roberts
- York Structural Biology Laboratory, Department of Chemistry, The University of York, York YO10 5DD, England
| | - Stuart McNicholas
- York Structural Biology Laboratory, Department of Chemistry, The University of York, York YO10 5DD, England
| | | | | | - Jan Dohnalek
- York Structural Biology Laboratory, Department of Chemistry, The University of York, York YO10 5DD, England
| | - Kevin D. Cowtan
- York Structural Biology Laboratory, Department of Chemistry, The University of York, York YO10 5DD, England
| | - Gideon J. Davies
- York Structural Biology Laboratory, Department of Chemistry, The University of York, York YO10 5DD, England
| | - Keith S. Wilson
- York Structural Biology Laboratory, Department of Chemistry, The University of York, York YO10 5DD, England
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Vladimirova A, Patskovsky Y, Fedorov AA, Bonanno JB, Fedorov EV, Toro R, Hillerich B, Seidel RD, Richards NGJ, Almo SC, Raushel FM. Substrate Distortion and the Catalytic Reaction Mechanism of 5-Carboxyvanillate Decarboxylase. J Am Chem Soc 2016; 138:826-36. [PMID: 26714575 PMCID: PMC4732527 DOI: 10.1021/jacs.5b08251] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
![]()
5-Carboxyvanillate
decarboxylase (LigW) catalyzes the conversion
of 5-carboxyvanillate to vanillate in the biochemical pathway for
the degradation of lignin. This enzyme was shown to require Mn2+ for catalytic activity and the kinetic constants for the
decarboxylation of 5-carboxyvanillate by the enzymes from Sphingomonas paucimobilis SYK-6 (kcat = 2.2 s–1 and kcat/Km = 4.0 × 104 M–1 s–1) and Novosphingobium aromaticivorans (kcat = 27 s–1 and kcat/Km = 1.1 × 105 M–1 s–1) were determined. The three-dimensional structures of both enzymes
were determined in the presence and absence of ligands bound in the
active site. The structure of LigW from N. aromaticivorans, bound with the substrate analogue, 5-nitrovanillate (Kd = 5.0 nM), was determined to a resolution of 1.07 Å.
The structure of this complex shows a remarkable enzyme-induced distortion
of the nitro-substituent out of the plane of the phenyl ring by approximately
23°. A chemical reaction mechanism for the decarboxylation of
5-carboxyvanillate by LigW was proposed on the basis of the high resolution
X-ray structures determined in the presence ligands bound in the active
site, mutation of active site residues, and the magnitude of the product
isotope effect determined in a mixture of H2O and D2O. In the proposed reaction mechanism the enzyme facilitates
the transfer of a proton to C5 of the substrate prior to the decarboxylation
step.
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Affiliation(s)
- Anna Vladimirova
- Department of Chemistry, Texas A&M University , College Station, Texas 77843, United States
| | - Yury Patskovsky
- Department of Biochemistry, Albert Einstein College of Medicine , 1300 Morris Park Avenue, Bronx, New York 10461, United States
| | - Alexander A Fedorov
- Department of Biochemistry, Albert Einstein College of Medicine , 1300 Morris Park Avenue, Bronx, New York 10461, United States
| | - Jeffrey B Bonanno
- Department of Biochemistry, Albert Einstein College of Medicine , 1300 Morris Park Avenue, Bronx, New York 10461, United States
| | - Elena V Fedorov
- Department of Biochemistry, Albert Einstein College of Medicine , 1300 Morris Park Avenue, Bronx, New York 10461, United States
| | - Rafael Toro
- Department of Biochemistry, Albert Einstein College of Medicine , 1300 Morris Park Avenue, Bronx, New York 10461, United States
| | - Brandan Hillerich
- Department of Biochemistry, Albert Einstein College of Medicine , 1300 Morris Park Avenue, Bronx, New York 10461, United States
| | - Ronald D Seidel
- Department of Biochemistry, Albert Einstein College of Medicine , 1300 Morris Park Avenue, Bronx, New York 10461, United States
| | - Nigel G J Richards
- Department of Chemistry and Chemical Biology, Indiana University-Purdue University Indianapolis , Indianapolis, Indiana 46202, United States
| | - Steven C Almo
- Department of Biochemistry, Albert Einstein College of Medicine , 1300 Morris Park Avenue, Bronx, New York 10461, United States
| | - Frank M Raushel
- Department of Chemistry, Texas A&M University , College Station, Texas 77843, United States
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44
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Su H, Sheng X, Liu Y. Insights into the catalytic mechanism of N-acetylglucosaminidase glycoside hydrolase from Bacillus subtilis: a QM/MM study. Org Biomol Chem 2016; 14:3432-42. [DOI: 10.1039/c6ob00320f] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
QM/MM calculations on NagZs fromBacillus subtilisfurther confirm NagZs to be glycoside phosphorylases rather than glycoside hydrolases.
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Affiliation(s)
- Hao Su
- Key Laboratory of Colloid and Interface Chemistry
- Ministry of Education
- School of Chemistry and Chemical Engineering
- Shandong University
- Jinan
| | - Xiang Sheng
- Key Laboratory of Colloid and Interface Chemistry
- Ministry of Education
- School of Chemistry and Chemical Engineering
- Shandong University
- Jinan
| | - Yongjun Liu
- Key Laboratory of Colloid and Interface Chemistry
- Ministry of Education
- School of Chemistry and Chemical Engineering
- Shandong University
- Jinan
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45
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Qin Z, Xiao Y, Yang X, Mesters JR, Yang S, Jiang Z. A unique GCN5-related glucosamine N-acetyltransferase region exist in the fungal multi-domain glycoside hydrolase family 3 β-N-acetylglucosaminidase. Sci Rep 2015; 5:18292. [PMID: 26669854 PMCID: PMC4680927 DOI: 10.1038/srep18292] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2015] [Accepted: 11/16/2015] [Indexed: 11/17/2022] Open
Abstract
Glycoside hydrolase (GH) family 3 β-N-acetylglucosaminidases widely exist in the filamentous fungi, which may play a key role in chitin metabolism of fungi. A multi-domain GH family 3 β-N-acetylglucosaminidase from Rhizomucor miehei (RmNag), exhibiting a potential N-acetyltransferase region, has been recently reported to show great potential in industrial applications. In this study, the crystal structure of RmNag was determined at 2.80 Å resolution. The three-dimensional structure of RmNag showed four distinctive domains, which belong to two distinguishable functional regions — a GH family 3 β-N-acetylglucosaminidase region (N-terminal) and a N-acetyltransferase region (C-terminal). From structural and functional analysis, the C-terminal region of RmNag was identified as a unique tandem array linking general control non-derepressible 5 (GCN5)-related N-acetyltransferase (GNAT), which displayed glucosamine N-acetyltransferase activity. Structural analysis of this glucosamine N-acetyltransferase region revealed that a unique glucosamine binding pocket is located in the pantetheine arm binding terminal region of the conserved CoA binding pocket, which is different from all known GNAT members. This is the first structural report of a glucosamine N-acetyltransferase, which provides novel structural information about substrate specificity of GNATs. The structural and functional features of this multi-domain β-N-acetylglucosaminidase could be useful in studying the catalytic mechanism of GH family 3 proteins.
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Affiliation(s)
- Zhen Qin
- College of Food Science and Nutritional Engineering, Beijing Advanced Innovation Center for Food Nutrition and Human Health, China Agricultural University, Beijing 100083, China
| | - Yibei Xiao
- Institute of Biochemistry, Center for Structural and Cell Biology in Medicine, University of Lübeck, Ratzeburger Allee 160, 23538, Lübeck, Germany
| | - Xinbin Yang
- College of Food Science and Nutritional Engineering, Beijing Advanced Innovation Center for Food Nutrition and Human Health, China Agricultural University, Beijing 100083, China
| | - Jeroen R Mesters
- Institute of Biochemistry, Center for Structural and Cell Biology in Medicine, University of Lübeck, Ratzeburger Allee 160, 23538, Lübeck, Germany
| | - Shaoqing Yang
- College of Food Science and Nutritional Engineering, Beijing Advanced Innovation Center for Food Nutrition and Human Health, China Agricultural University, Beijing 100083, China
| | - Zhengqiang Jiang
- College of Food Science and Nutritional Engineering, Beijing Advanced Innovation Center for Food Nutrition and Human Health, China Agricultural University, Beijing 100083, China
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46
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Gregg KJ, Suits MDL, Deng L, Vocadlo DJ, Boraston AB. Structural Analysis of a Family 101 Glycoside Hydrolase in Complex with Carbohydrates Reveals Insights into Its Mechanism. J Biol Chem 2015; 290:25657-69. [PMID: 26304114 DOI: 10.1074/jbc.m115.680470] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Indexed: 11/06/2022] Open
Abstract
O-Linked glycosylation is one of the most abundant post-translational modifications of proteins. Within the secretory pathway of higher eukaryotes, the core of these glycans is frequently an N-acetylgalactosamine residue that is α-linked to serine or threonine residues. Glycoside hydrolases in family 101 are presently the only known enzymes to be able to hydrolyze this glycosidic linkage. Here we determine the high-resolution structures of the catalytic domain comprising a fragment of GH101 from Streptococcus pneumoniae TIGR4, SpGH101, in the absence of carbohydrate, and in complex with reaction products, inhibitor, and substrate analogues. Upon substrate binding, a tryptophan lid (residues 724-WNW-726) closes on the substrate. The closing of this lid fully engages the substrate in the active site with Asp-764 positioned directly beneath C1 of the sugar residue bound within the -1 subsite, consistent with its proposed role as the catalytic nucleophile. In all of the bound forms of the enzyme, however, the proposed catalytic acid/base residue was found to be too distant from the glycosidic oxygen (>4.3 Å) to serve directly as a general catalytic acid/base residue and thereby facilitate cleavage of the glycosidic bond. These same complexes, however, revealed a structurally conserved water molecule positioned between the catalytic acid/base and the glycosidic oxygen. On the basis of these structural observations we propose a new variation of the retaining glycoside hydrolase mechanism wherein the intervening water molecule enables a Grotthuss proton shuttle between Glu-796 and the glycosidic oxygen, permitting this residue to serve as the general acid/base catalytic residue.
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Affiliation(s)
- Katie J Gregg
- From the Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia, V8W 3P6 and
| | - Michael D L Suits
- From the Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia, V8W 3P6 and
| | - Lehua Deng
- the Department of Chemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada
| | - David J Vocadlo
- the Department of Chemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada
| | - Alisdair B Boraston
- From the Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia, V8W 3P6 and
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47
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Kitaoka M. Diversity of phosphorylases in glycoside hydrolase families. Appl Microbiol Biotechnol 2015; 99:8377-90. [PMID: 26293338 DOI: 10.1007/s00253-015-6927-0] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Accepted: 08/05/2015] [Indexed: 01/02/2023]
Abstract
Phosphorylases are useful catalysts for the practical preparation of various sugars. The number of known specificities was 13 in 2002 and is now 30. The drastic increase in available genome sequences has facilitated the discovery of novel activities. Most of these novel phosphorylase activities have been identified through the investigations of glycoside hydrolase families containing known phosphorylases. Here, the diversity of phosphorylases in each family is described in detail.
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Affiliation(s)
- Motomitsu Kitaoka
- National Food Research Institute, National Agriculture and Food Research Organization, 2-1-12 Kannondai, Tsukuba, Ibaraki, 305-8642, Japan.
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48
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Kim JS, Yoon BY, Ahn J, Cha J, Ha NC. Crystal structure of β-N-acetylglucosaminidase CbsA from Thermotoga neapolitana. Biochem Biophys Res Commun 2015; 464:869-74. [DOI: 10.1016/j.bbrc.2015.07.053] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Accepted: 07/09/2015] [Indexed: 10/23/2022]
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49
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Panigrahi K, Applegate GA, Malik G, Berkowitz DB. Combining a Clostridial enzyme exhibiting unusual active site plasticity with a remarkably facile sigmatropic rearrangement: rapid, stereocontrolled entry into densely functionalized fluorinated phosphonates for chemical biology. J Am Chem Soc 2015; 137:3600-9. [PMID: 25719907 DOI: 10.1021/jacs.5b00022] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Described is an efficient stereocontrolled route into valuable, densely functionalized fluorinated phosphonates that takes advantage of (i) a Clostridial enzyme to set the absolute stereochemistry and (ii) a new [3,3]-sigmatropic rearrangement of the thiono-Claisen variety that is among the fastest sigmatropic rearrangements yet reported. Here, a pronounced rate enhancement is achieved by distal fluorination. This rearrangement is completely stereoretentive, parlaying the enzymatically established β-C-O stereochemistry in the substrate into the δ-C-S stereochemistry in the product. The final products are of interest to chemical biology, with a platform for Zn-aminopeptidase A inhibitors being constructed here. The enzyme, Clostridium acetobutylicum (CaADH), recently expressed by our group, reduces a spectrum of γ,δ-unsaturated β-keto-α,α-difluorophosphonate esters (93-99% ee; 10 examples). The resultant β-hydroxy-α,α-difluorophosphonates possess the "L"-stereochemistry, opposite to that previously observed for the CaADH-reduction of ω-keto carboxylate esters ("D"), indicating an unusual active site plasticity. For the thiono-Claisen rearrangement, a notable structure-reactivity relationship is observed. Measured rate constants vary by over 3 orders of magnitude, depending upon thiono-ester structure. Temperature-dependent kinetics reveal an unusually favorable entropy of activation (ΔS(‡) = 14.5 ± 0.6 e.u.). Most notably, a 400-fold rate enhancement is seen upon fluorination of the distal arene ring, arising from favorable enthalpic (ΔΔH(‡) = -2.3 kcal/mol) and entropic (ΔΔS(‡) = 4 e.u., i.e. 1.2 kcal/mol at rt) contributions. The unusual active site plasticity seen here is expected to drive structural biology studies on CaADH, while the exceptionally facile sigmatropic rearrangement is expected to drive computational studies to elucidate its underlying entropic and enthalpic basis.
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Affiliation(s)
- Kaushik Panigrahi
- Department of Chemistry, University of Nebraska, Lincoln, Nebraska 68588-0304, United States
| | - Gregory A Applegate
- Department of Chemistry, University of Nebraska, Lincoln, Nebraska 68588-0304, United States
| | - Guillaume Malik
- Department of Chemistry, University of Nebraska, Lincoln, Nebraska 68588-0304, United States
| | - David B Berkowitz
- Department of Chemistry, University of Nebraska, Lincoln, Nebraska 68588-0304, United States
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50
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Gabriško M, Janeček Š. Novel family GH3 β-glucosidases or β-xylosidases of unknown function found in various animal groups, including birds and reptiles. Carbohydr Res 2015; 408:44-50. [PMID: 25841058 DOI: 10.1016/j.carres.2015.02.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2014] [Revised: 02/04/2015] [Accepted: 02/07/2015] [Indexed: 11/26/2022]
Abstract
Proteins from the glycoside hydrolase family 3 (GH3) are important bacterial, fungal and plant enzymes involved in cell wall remodeling, energy metabolism and pathogen defense but no animal GH3 proteins have been reported so far. In presented work we use the in silico approach to describe putative GH3 proteins of animals. Based on tertiary structure modeling, domain organization and transcriptomics data analysis, presence of catalytic and substrate binding residues and evolutionary relationship inference, we assume that there is a monophyletic group of GH3 enzymes (probably β-xylosidases) found in various animal taxa with possible role in development.
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Affiliation(s)
- Marek Gabriško
- Laboratory of Protein Evolution, Institute of Molecular Biology, Slovak Academy of Sciences, Dúbravská cesta 21, SK-84551 Bratislava, Slovakia.
| | - Štefan Janeček
- Laboratory of Protein Evolution, Institute of Molecular Biology, Slovak Academy of Sciences, Dúbravská cesta 21, SK-84551 Bratislava, Slovakia
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