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Scalabrini M, Loquet D, Rochard C, Baudin Marie M, Assailly C, Brissonnet Y, Daligault F, Saumonneau A, Lambert A, Grandjean C, Deniaud D, Lottin P, Pascual S, Fontaine L, Balloy V, Gouin SG. Multivalent inhibition of the Aspergillus fumigatus KDNase. Org Biomol Chem 2024; 22:5783-5789. [PMID: 38938184 DOI: 10.1039/d4ob00601a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/29/2024]
Abstract
Aspergillus fumigatus is a saprophytic fungus and opportunistic pathogen often causing fatal infections in immunocompromised patients. Recently AfKDNAse, an exoglycosidase hydrolyzing 3-deoxy-D-galacto-D-glycero-nonulosonic acid (KDN), a rare sugar from the sialic acid family, was identified and characterized. The principal function of AfKDNAse is still unclear, but a study suggests a critical role in fungal cell wall morphology and virulence. Potent AfKDNAse inhibitors are required to better probe the enzyme's biological role and as potential antivirulence factors. In this work, we developed a set of AfKDNAse inhibitors based on enzymatically stable thio-KDN motifs. C2, C9-linked heterodi-KDN were designed to fit into unusually close KDN sugar binding pockets in the protein. A polymeric compound with an average of 54 KDN motifs was also designed by click chemistry. Inhibitory assays performed on recombinant AfKDNAse showed a moderate and strong enzymatic inhibition for the two classes of compounds, respectively. The poly-KDN showed more than a nine hundred fold improved inhibitory activity (IC50 = 1.52 ± 0.37 μM, 17-fold in a KDN molar basis) compared to a monovalent KDN reference, and is to our knowledge, the best synthetic inhibitor described for a KDNase. Multivalency appears to be a relevant strategy for the design of potent KDNase inhibitors. Importantly, poly-KDN was shown to strongly decrease filamentation when co-cultured with A. fumigatus at micromolar concentrations, opening interesting perspectives in the development of antivirulence factors.
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Affiliation(s)
| | - Denis Loquet
- Nantes Université, CNRS, CEISAM, UMR 6230, F-44000 Nantes, France.
| | - Camille Rochard
- Sorbonne Université, Inserm, Centre de Recherche Saint-Antoine, CRSA, Paris, France
| | | | - Coralie Assailly
- Nantes Université, CNRS, CEISAM, UMR 6230, F-44000 Nantes, France.
| | - Yoan Brissonnet
- Nantes Université, CNRS, CEISAM, UMR 6230, F-44000 Nantes, France.
| | - Franck Daligault
- Nantes Université, CNRS, US2B, UMR 6286, F-44000 Nantes, France 2 rue de la Houssinière, BP 92208, 44322 Nantes Cedex 3, France
| | - Amélie Saumonneau
- Nantes Université, CNRS, US2B, UMR 6286, F-44000 Nantes, France 2 rue de la Houssinière, BP 92208, 44322 Nantes Cedex 3, France
| | - Annie Lambert
- Nantes Université, CNRS, US2B, UMR 6286, F-44000 Nantes, France 2 rue de la Houssinière, BP 92208, 44322 Nantes Cedex 3, France
| | - Cyrille Grandjean
- Nantes Université, CNRS, US2B, UMR 6286, F-44000 Nantes, France 2 rue de la Houssinière, BP 92208, 44322 Nantes Cedex 3, France
| | - David Deniaud
- Nantes Université, CNRS, CEISAM, UMR 6230, F-44000 Nantes, France.
| | - Paul Lottin
- Institut des Molécules et Matériaux du Mans (IMMM), UMR 6283 CNRS, Le Mans Université, Av. O. Messiaen, 72085 Le Mans cedex 9, France
| | - Sagrario Pascual
- Institut des Molécules et Matériaux du Mans (IMMM), UMR 6283 CNRS, Le Mans Université, Av. O. Messiaen, 72085 Le Mans cedex 9, France
| | - Laurent Fontaine
- Institut des Molécules et Matériaux du Mans (IMMM), UMR 6283 CNRS, Le Mans Université, Av. O. Messiaen, 72085 Le Mans cedex 9, France
| | - Viviane Balloy
- Sorbonne Université, Inserm, Centre de Recherche Saint-Antoine, CRSA, Paris, France
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2
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Strader MB, Saha AL, Fernandes C, Sharma K, Hadiwinarta C, Calheiros D, Conde-de-Oliveira G, Gonçalves T, Slater JE. Distinct proteomes and allergen profiles appear across the life-cycle stages of Alternaria alternata. J Allergy Clin Immunol 2024:S0091-6749(24)00410-X. [PMID: 38663817 DOI: 10.1016/j.jaci.2024.03.026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Revised: 03/01/2024] [Accepted: 03/20/2024] [Indexed: 05/26/2024]
Abstract
BACKGROUND Alternaria alternata is associated with allergic respiratory diseases, which can be managed with allergen extract-based diagnostics and immunotherapy. It is not known how spores and hyphae contribute to allergen content. Commercial allergen extracts are manufactured by extracting proteins without separating the different forms of the fungus. OBJECTIVE We sought to determine differences between spore and hyphae proteomes and how allergens are distributed in Aalternata. METHODS Data-independent acquisition mass spectrometry was used to quantitatively compare the proteomes of asexual spores (nongerminating and germinating) with vegetative hyphae. RESULTS We identified 4515 proteins in nongerminating spores, germinating spores, and hyphae; most known allergens are more abundant in nongerminating spores. On comparing significant protein fold-change differences between nongerminating spores and hyphae, we found that 174 proteins were upregulated in nongerminating spores and 80 proteins in hyphae. Among the spore proteins are ones functionally involved in cell wall synthesis, responding to cellular stress, and maintaining redox balance and homeostasis. On comparing nongerminating and germinating spores, 25 proteins were found to be upregulated in nongerminating spores and 54 in germinating spores. Among the proteins specific to germinating spores were proteases known to be virulence factors. One of the most abundant proteins in the spore proteome is sialidase, which has not been identified as an allergen but may be important in the pathogenicity of this fungus. Major allergen Alt a 1 is present at low levels in spores and hyphae and appears to be largely secreted into growth media. CONCLUSIONS Spores and hyphae express overlapping but distinct proteomes. Most known allergens are found more abundantly in nongerminating spores.
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Affiliation(s)
- Michael Brad Strader
- Laboratory of Immunobiochemistry, Division of Bacterial, Parasitic and Allergenic Products, Office of Vaccines Research and Review, Center for Biologics Evaluation and Research, US Food and Drug Administration, Silver Spring, Md.
| | - Aishwarya L Saha
- Laboratory of Immunobiochemistry, Division of Bacterial, Parasitic and Allergenic Products, Office of Vaccines Research and Review, Center for Biologics Evaluation and Research, US Food and Drug Administration, Silver Spring, Md
| | - Chantal Fernandes
- University of Coimbra, CNC-UC - Center for Neuroscience and Cell Biology, FMUC - Faculty of Medicine of the University of Coimbra, Coimbra, Portugal
| | - Kavita Sharma
- Laboratory of Immunobiochemistry, Division of Bacterial, Parasitic and Allergenic Products, Office of Vaccines Research and Review, Center for Biologics Evaluation and Research, US Food and Drug Administration, Silver Spring, Md
| | - Christian Hadiwinarta
- Laboratory of Immunobiochemistry, Division of Bacterial, Parasitic and Allergenic Products, Office of Vaccines Research and Review, Center for Biologics Evaluation and Research, US Food and Drug Administration, Silver Spring, Md
| | - Daniela Calheiros
- University of Coimbra, CNC-UC - Center for Neuroscience and Cell Biology, FMUC - Faculty of Medicine of the University of Coimbra, Coimbra, Portugal
| | - Gonçalo Conde-de-Oliveira
- University of Coimbra, CNC-UC - Center for Neuroscience and Cell Biology, FMUC - Faculty of Medicine of the University of Coimbra, Coimbra, Portugal
| | - Teresa Gonçalves
- University of Coimbra, CNC-UC - Center for Neuroscience and Cell Biology, FMUC - Faculty of Medicine of the University of Coimbra, Coimbra, Portugal
| | - Jay E Slater
- Laboratory of Immunobiochemistry, Division of Bacterial, Parasitic and Allergenic Products, Office of Vaccines Research and Review, Center for Biologics Evaluation and Research, US Food and Drug Administration, Silver Spring, Md
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3
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Abrashev R, Krumova E, Petrova P, Eneva R, Dishliyska V, Gocheva Y, Engibarov S, Miteva-Staleva J, Spasova B, Kolyovska V, Angelova M. Glucose Catabolite Repression Participates in the Regulation of Sialidase Biosynthesis by Antarctic Strain Penicillium griseofulvum P29. J Fungi (Basel) 2024; 10:241. [PMID: 38667912 PMCID: PMC11051313 DOI: 10.3390/jof10040241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2024] [Revised: 03/18/2024] [Accepted: 03/21/2024] [Indexed: 04/28/2024] Open
Abstract
Sialidases (neuraminidases) catalyze the removal of terminal sialic acid residues from glycoproteins. Novel enzymes from non-clinical isolates are of increasing interest regarding their application in the food and pharmaceutical industry. The present study aimed to evaluate the participation of carbon catabolite repression (CCR) in the regulation of cold-active sialidase biosynthesis by the psychrotolerant fungal strain Penicillium griseofulvum P29, isolated from Antarctica. The presence of glucose inhibited sialidase activity in growing and non-growing fungal mycelia in a dose- and time-dependent manner. The same response was demonstrated with maltose and sucrose. The replacement of glucose with glucose-6-phosphate also exerted CCR. The addition of cAMP resulted in the partial de-repression of sialidase synthesis. The CCR in the psychrotolerant strain P. griseofulvum P29 did not depend on temperature. Sialidase might be subject to glucose repression by both at 10 and 25 °C. The fluorescent assay using 4MU-Neu5Ac for enzyme activity determination under increasing glucose concentrations evidenced that CCR may have a regulatory role in sialidase production. The real-time RT-PCR experiments revealed that the sialidase gene was subject to glucose repression. To our knowledge, this is the first report that has studied the effect of CCR on cold-active sialidase, produced by an Antarctic strain.
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Affiliation(s)
- Radoslav Abrashev
- Department of Mycology, The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, Academician G. Bonchev 26, 1113 Sofia, Bulgaria; (R.A.); (E.K.); (V.D.); (J.M.-S.); (B.S.)
| | - Ekaterina Krumova
- Department of Mycology, The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, Academician G. Bonchev 26, 1113 Sofia, Bulgaria; (R.A.); (E.K.); (V.D.); (J.M.-S.); (B.S.)
| | - Penka Petrova
- Department of General Microbiology, The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, Academician G. Bonchev 26, 1113 Sofia, Bulgaria; (P.P.); (R.E.); (Y.G.); (S.E.)
| | - Rumyana Eneva
- Department of General Microbiology, The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, Academician G. Bonchev 26, 1113 Sofia, Bulgaria; (P.P.); (R.E.); (Y.G.); (S.E.)
| | - Vladislava Dishliyska
- Department of Mycology, The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, Academician G. Bonchev 26, 1113 Sofia, Bulgaria; (R.A.); (E.K.); (V.D.); (J.M.-S.); (B.S.)
| | - Yana Gocheva
- Department of General Microbiology, The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, Academician G. Bonchev 26, 1113 Sofia, Bulgaria; (P.P.); (R.E.); (Y.G.); (S.E.)
| | - Stefan Engibarov
- Department of General Microbiology, The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, Academician G. Bonchev 26, 1113 Sofia, Bulgaria; (P.P.); (R.E.); (Y.G.); (S.E.)
| | - Jeny Miteva-Staleva
- Department of Mycology, The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, Academician G. Bonchev 26, 1113 Sofia, Bulgaria; (R.A.); (E.K.); (V.D.); (J.M.-S.); (B.S.)
| | - Boryana Spasova
- Department of Mycology, The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, Academician G. Bonchev 26, 1113 Sofia, Bulgaria; (R.A.); (E.K.); (V.D.); (J.M.-S.); (B.S.)
| | - Vera Kolyovska
- Institute of Experimental Morphology, Pathology and Anthropology with Museum, Bulgarian Academy of Sciences, Academician G. Bonchev 25, 1113 Sofia, Bulgaria;
| | - Maria Angelova
- Department of Mycology, The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, Academician G. Bonchev 26, 1113 Sofia, Bulgaria; (R.A.); (E.K.); (V.D.); (J.M.-S.); (B.S.)
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4
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Dolashki A, Abrashev R, Kaynarov D, Krumova E, Velkova L, Eneva R, Engibarov S, Gocheva Y, Miteva-Staleva J, Dishliyska V, Spasova B, Angelova M, Dolashka P. Structural and functional characterization of cold-active sialidase isolated from Antarctic fungus Penicillium griseofulvum P29. Biochem Biophys Rep 2024; 37:101610. [PMID: 38155944 PMCID: PMC10753047 DOI: 10.1016/j.bbrep.2023.101610] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Revised: 12/05/2023] [Accepted: 12/08/2023] [Indexed: 12/30/2023] Open
Abstract
The fungal strain, Penicillium griseofulvum P29, isolated from a soil sample taken from Terra Nova Bay, Antarctica, was found to be a good producer of sialidase (P29). The present study was focused on the purification and structural characterization of the enzyme. P29 enzyme was purified using a Q-Sepharose column and fast performance liquid chromatography separation on a Mono Q column. The determined molecular mass of the purified enzyme of 40 kDa by SDS-PAGE and 39924.40 Da by matrix desorption/ionization mass spectrometry (MALDI-TOF/MS) analysis correlated well with the calculated mass (39903.75 kDa) from the amino acid sequence of the enzyme. P29 sialidase shows a temperature optimum of 37 °C and low-temperature stability, confirming its cold-active nature. The enzyme is more active towards α(2 → 3) sialyl linkages than those containing α(2 → 6) linkages. Based on the determined amino acid sequence and 3D structural modeling, a 3D model of P29 sialidase was presented, and the properties of the enzyme were explained. The conformational stability of the enzyme was followed by fluorescence spectroscopy, and the new enzyme was found to be conformationally stable in the neutral pH range of pH 6 to pH 9. In addition, the enzyme was more stable in an alkaline environment than in an acidic environment. The purified cold-active enzyme is the only sialidase produced and characterized from Antarctic fungi to date.
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Affiliation(s)
- Aleksandar Dolashki
- Institute of Organic Chemistry with Centre of Phytochemistry, Bulgarian Academy of Sciences, Sofia, 1113, Acad. Georgy Bonchev str., bl. 9, Bulgaria
| | - Radoslav Abrashev
- The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, Sofia, 1113, Acad. G. Bonchev str., bl. 26, Bulgaria
| | - Dimitar Kaynarov
- Institute of Organic Chemistry with Centre of Phytochemistry, Bulgarian Academy of Sciences, Sofia, 1113, Acad. Georgy Bonchev str., bl. 9, Bulgaria
| | - Ekaterina Krumova
- The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, Sofia, 1113, Acad. G. Bonchev str., bl. 26, Bulgaria
| | - Lyudmila Velkova
- Institute of Organic Chemistry with Centre of Phytochemistry, Bulgarian Academy of Sciences, Sofia, 1113, Acad. Georgy Bonchev str., bl. 9, Bulgaria
| | - Rumyana Eneva
- The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, Sofia, 1113, Acad. G. Bonchev str., bl. 26, Bulgaria
| | - Stefan Engibarov
- The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, Sofia, 1113, Acad. G. Bonchev str., bl. 26, Bulgaria
| | - Yana Gocheva
- The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, Sofia, 1113, Acad. G. Bonchev str., bl. 26, Bulgaria
| | - Jeny Miteva-Staleva
- The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, Sofia, 1113, Acad. G. Bonchev str., bl. 26, Bulgaria
| | - Vladislava Dishliyska
- The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, Sofia, 1113, Acad. G. Bonchev str., bl. 26, Bulgaria
| | - Boryana Spasova
- The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, Sofia, 1113, Acad. G. Bonchev str., bl. 26, Bulgaria
| | - Maria Angelova
- The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, Sofia, 1113, Acad. G. Bonchev str., bl. 26, Bulgaria
| | - Pavlina Dolashka
- Institute of Organic Chemistry with Centre of Phytochemistry, Bulgarian Academy of Sciences, Sofia, 1113, Acad. Georgy Bonchev str., bl. 9, Bulgaria
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5
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Gorelik A, Illes K, Mazhab-Jafari MT, Nagar B. Structure of the immunoregulatory sialidase NEU1. SCIENCE ADVANCES 2023; 9:eadf8169. [PMID: 37205763 DOI: 10.1126/sciadv.adf8169] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Accepted: 04/14/2023] [Indexed: 05/21/2023]
Abstract
Sialic acids linked to glycoproteins and glycolipids are important mediators of cell and protein recognition events. These sugar residues are removed by neuraminidases (sialidases). Neuraminidase-1 (sialidase-1 or NEU1) is a ubiquitously expressed mammalian sialidase located in lysosomes and on the cell membrane. Because of its modulation of multiple signaling processes, it is a potential therapeutic target for cancers and immune disorders. Genetic defects in NEU1 or in its protective protein cathepsin A (PPCA, CTSA) cause the lysosomal storage diseases sialidosis and galactosialidosis. To further our understanding of this enzyme's function at the molecular level, we determined the three-dimensional structure of murine NEU1. The enzyme oligomerizes through two self-association interfaces and displays a wide substrate-binding cavity. A catalytic loop adopts an inactive conformation. We propose a mechanism of activation involving a conformational change in this loop upon binding to its protective protein. These findings may facilitate the development of selective inhibitor and agonist therapies.
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Affiliation(s)
- Alexei Gorelik
- Department of Biochemistry, McGill University, Montreal, Quebec, Canada
| | - Katalin Illes
- Department of Biochemistry, McGill University, Montreal, Quebec, Canada
| | - Mohammad T Mazhab-Jafari
- Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada
- Princess Margaret Cancer Center, University Health Network, Toronto, Ontario, Canada
| | - Bhushan Nagar
- Department of Biochemistry, McGill University, Montreal, Quebec, Canada
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6
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Dong WB, Jiang YL, Zhu ZL, Zhu J, Li Y, Xia R, Zhou K. Structural and enzymatic characterization of the sialidase SiaPG from Porphyromonas gingivalis. Acta Crystallogr F Struct Biol Commun 2023; 79:87-94. [PMID: 36995120 PMCID: PMC10071834 DOI: 10.1107/s2053230x23001735] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Accepted: 02/24/2023] [Indexed: 03/31/2023] Open
Abstract
The sialidases, which catalyze the hydrolysis of sialic acid from extracellular glycoconjugates, are a group of major virulence factors in various pathogenic bacteria. In Porphyromonas gingivalis, which causes human periodontal disease, sialidase contributes to bacterial pathogenesis via promoting the formation of biofilms and capsules, reducing the ability for macrophage clearance, and providing nutrients for bacterial colonization. Here, the crystal structure of the P. gingivalis sialidase SiaPG is reported at 2.1 Å resolution, revealing an N-terminal carbohydrate-binding domain followed by a canonical C-terminal catalytic domain. Simulation of the product sialic acid in the active-site pocket together with functional analysis enables clear identification of the key residues that are required for substrate binding and catalysis. Moreover, structural comparison with other sialidases reveals distinct features of the active-site pocket which might confer substrate specificity. These findings provide the structural basis for the further design and optimization of effective inhibitors to target SiaPG to fight against P. gingivalis-derived oral diseases.
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Affiliation(s)
- Wen-Bo Dong
- Department of Stomatology, The Second Affiliated Hospital of Anhui Medical University, Hefei, Anhui 230601, People’s Republic of China
| | - Yong-Liang Jiang
- School of Life Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui 230026, People’s Republic of China
| | - Zhong-Liang Zhu
- School of Life Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui 230026, People’s Republic of China
| | - Jie Zhu
- School of Life Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui 230026, People’s Republic of China
| | - Yang Li
- School of Life Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui 230026, People’s Republic of China
| | - Rong Xia
- Department of Stomatology, The Second Affiliated Hospital of Anhui Medical University, Hefei, Anhui 230601, People’s Republic of China
| | - Kang Zhou
- School of Life Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui 230026, People’s Republic of China
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7
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Nejatie A, Colombo C, Hakak‐Zargar B, Bennet AJ. A Mechanistic Study on the Non‐enzymatic Hydrolysis of Kdn Glycosides. European J Org Chem 2022. [DOI: 10.1002/ejoc.202101387] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Ali Nejatie
- Department of Chemistry Simon Fraser University 8888 University Drive Burnaby British Columbia V5A 1S6 Canada
| | - Cinzia Colombo
- Department of Chemistry Simon Fraser University 8888 University Drive Burnaby British Columbia V5A 1S6 Canada
| | - Benyamin Hakak‐Zargar
- Department of Chemistry Simon Fraser University 8888 University Drive Burnaby British Columbia V5A 1S6 Canada
| | - Andrew J. Bennet
- Department of Chemistry Simon Fraser University 8888 University Drive Burnaby British Columbia V5A 1S6 Canada
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8
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Nejatie A, Steves E, Gauthier N, Baker J, Nesbitt J, McMahon SA, Oehler V, Thornton NJ, Noyovitz B, Khazaei K, Byers BW, Zandberg WF, Gloster TM, Moore MM, Bennet AJ. Kinetic and Structural Characterization of Sialidases (Kdnases) from Ascomycete Fungal Pathogens. ACS Chem Biol 2021; 16:2632-2640. [PMID: 34724608 DOI: 10.1021/acschembio.1c00666] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Sialidases catalyze the release of sialic acid from the terminus of glycan chains. We previously characterized the sialidase from the opportunistic fungal pathogen, Aspergillus fumigatus, and showed that it is a Kdnase. That is, this enzyme prefers 3-deoxy-d-glycero-d-galacto-non-2-ulosonates (Kdn glycosides) as the substrate compared to N-acetylneuraminides (Neu5Ac). Here, we report characterization and crystal structures of putative sialidases from two other ascomycete fungal pathogens, Aspergillus terreus (AtS) and Trichophyton rubrum (TrS). Unlike A. fumigatus Kdnase (AfS), hydrolysis with the Neu5Ac substrates was negligible for TrS and AtS; thus, TrS and AtS are selective Kdnases. The second-order rate constant for hydrolysis of aryl Kdn glycosides by AtS is similar to that by AfS but 30-fold higher by TrS. The structures of these glycoside hydrolase family 33 (GH33) enzymes in complex with a range of ligands for both AtS and TrS show subtle changes in ring conformation that mimic the Michaelis complex, transition state, and covalent intermediate formed during catalysis. In addition, they can aid identification of important residues for distinguishing between Kdn and Neu5Ac substrates. When A. fumigatus, A. terreus, and T. rubrum were grown in chemically defined media, Kdn was detected in mycelial extracts, but Neu5Ac was only observed in A. terreus or T. rubrum extracts. The C8 monosaccharide 3-deoxy-d-manno-oct-2-ulosonic acid (Kdo) was also identified in A. fumigatus and T. rubrum samples. A fluorescent Kdn probe was synthesized and revealed the localization of AfS in vesicles at the cell surface.
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Affiliation(s)
- Ali Nejatie
- Department of Chemistry, Simon Fraser University, 8888 University Drive, Burnaby V5A 1S6, British
Columbia, Canada
| | - Elizabeth Steves
- Department of Biological Sciences, Simon Fraser University, 8888 University Drive, Burnaby V5A 1S6, British
Columbia, Canada
| | - Nick Gauthier
- Department of Biological Sciences, Simon Fraser University, 8888 University Drive, Burnaby V5A 1S6, British
Columbia, Canada
| | - Jamie Baker
- Department of Biological Sciences, Simon Fraser University, 8888 University Drive, Burnaby V5A 1S6, British
Columbia, Canada
| | - Jason Nesbitt
- Department of Biological Sciences, Simon Fraser University, 8888 University Drive, Burnaby V5A 1S6, British
Columbia, Canada
| | - Stephen A. McMahon
- Biomedical Sciences Research Complex, University of St Andrews, St Andrews KY16 9ST, Fife, U.K
| | - Verena Oehler
- Biomedical Sciences Research Complex, University of St Andrews, St Andrews KY16 9ST, Fife, U.K
| | - Nicholas J. Thornton
- Biomedical Sciences Research Complex, University of St Andrews, St Andrews KY16 9ST, Fife, U.K
| | - Benjamin Noyovitz
- Department of Chemistry, I. K. Barber Faculty of Science, University of British Columbia, 3247 University Way, Kelowna V1V 1V7, British Columbia, Canada
| | - Kobra Khazaei
- Department of Chemistry, Simon Fraser University, 8888 University Drive, Burnaby V5A 1S6, British
Columbia, Canada
| | - Brock W. Byers
- Department of Chemistry, Simon Fraser University, 8888 University Drive, Burnaby V5A 1S6, British
Columbia, Canada
| | - Wesley F. Zandberg
- Department of Chemistry, I. K. Barber Faculty of Science, University of British Columbia, 3247 University Way, Kelowna V1V 1V7, British Columbia, Canada
| | - Tracey M. Gloster
- Biomedical Sciences Research Complex, University of St Andrews, St Andrews KY16 9ST, Fife, U.K
| | - Margo M. Moore
- Department of Biological Sciences, Simon Fraser University, 8888 University Drive, Burnaby V5A 1S6, British
Columbia, Canada
| | - Andrew J. Bennet
- Department of Chemistry, Simon Fraser University, 8888 University Drive, Burnaby V5A 1S6, British
Columbia, Canada
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9
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Yu ACY, Volkers G, Jongkees SAK, Worrall LJ, Withers SG, Strynadka NCJ. Crystal structure of the Propionibacterium acnes surface sialidase, a drug target for P. acnes-associated diseases. Glycobiology 2021; 32:162-170. [PMID: 34792586 DOI: 10.1093/glycob/cwab094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Revised: 04/28/2021] [Accepted: 05/19/2021] [Indexed: 11/12/2022] Open
Abstract
Propionibacterium acnes, though generally considered part of the normal flora of human skin, is an opportunistic pathogen associated with acne vulgaris as well as other diseases, including endocarditis, endophthalmitis and prosthetic joint infections. Its virulence potential is also supported by knowledge gained from its sequenced genome. Indeed, a vaccine targeting a putative cell wall-anchored P. acnes sialidase has been shown to suppress cytotoxicity and pro-inflammatory cytokine release induced by the organism, and is proposed as an alternative treatment for P. acnes-associated diseases. Here, we report the crystal structures of the surface sialidase and its complex with the transition-state mimic Neu5Ac2en. Our structural and kinetic analyses, together with insight from a glycan array screen, which probes subtle specificities of the sialidase for α-2,3-sialosides, provide a basis for the structure-based design of novel small-molecule therapeutics against P. acnes infections.
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Affiliation(s)
- Angel C Y Yu
- Department of Biochemistry and Molecular Biology, University of British Columbia, 2350 Health Sciences Mall, Vancouver, British Columbia V6T 1Z3, Canada.,Centre for Blood Research, University of British Columbia, Vancouver, British Columbia, 2350 Health Sciences Mall, V6T 1Z3, Canada
| | - Gesa Volkers
- Department of Biochemistry and Molecular Biology, University of British Columbia, 2350 Health Sciences Mall, Vancouver, British Columbia V6T 1Z3, Canada.,Centre for Blood Research, University of British Columbia, Vancouver, British Columbia, 2350 Health Sciences Mall, V6T 1Z3, Canada
| | - Seino A K Jongkees
- Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, British Columbia, V6T 1Z1, Canada
| | - Liam J Worrall
- Department of Biochemistry and Molecular Biology, University of British Columbia, 2350 Health Sciences Mall, Vancouver, British Columbia V6T 1Z3, Canada.,Centre for Blood Research, University of British Columbia, Vancouver, British Columbia, 2350 Health Sciences Mall, V6T 1Z3, Canada
| | - Stephen G Withers
- Department of Biochemistry and Molecular Biology, University of British Columbia, 2350 Health Sciences Mall, Vancouver, British Columbia V6T 1Z3, Canada.,Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, British Columbia, V6T 1Z1, Canada
| | - Natalie C J Strynadka
- Department of Biochemistry and Molecular Biology, University of British Columbia, 2350 Health Sciences Mall, Vancouver, British Columbia V6T 1Z3, Canada.,Centre for Blood Research, University of British Columbia, Vancouver, British Columbia, 2350 Health Sciences Mall, V6T 1Z3, Canada
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10
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Dewi IM, Cunha C, Jaeger M, Gresnigt MS, Gkountzinopoulou ME, Garishah FM, Duarte-Oliveira C, Campos CF, Vanderbeke L, Sharpe AR, Brüggemann RJ, Verweij PE, Lagrou K, Vande Velde G, de Mast Q, Joosten LA, Netea MG, van der Ven AJ, Wauters J, Carvalho A, van de Veerdonk FL. Neuraminidase and SIGLEC15 modulate the host defense against pulmonary aspergillosis. Cell Rep Med 2021; 2:100289. [PMID: 34095887 PMCID: PMC8149467 DOI: 10.1016/j.xcrm.2021.100289] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Revised: 09/01/2020] [Accepted: 04/23/2021] [Indexed: 11/30/2022]
Abstract
Influenza-associated pulmonary aspergillosis (IAPA) has been reported increasingly since the advent of use of neuraminidase (NA) inhibitors following the 2009 influenza pandemic. We hypothesize that blocking host NA modulates the immune response against Aspergillus fumigatus. We demonstrate that NA influences the host response against A. fumigatus in vitro and that oseltamivir increases the susceptibility of mice to pulmonary aspergillosis. Oseltamivir impairs the mouse splenocyte and human peripheral blood mononuclear cell (PBMC) killing capacity of A. fumigatus, and adding NA restores this defect in PBMCs. Furthermore, the sialic acid-binding receptor SIGLEC15 is upregulated in PBMCs stimulated with A. fumigatus. Silencing of SIGLEC15 decrease PBMC killing of A. fumigatus. We provide evidence that host NA activity and sialic acid recognition are important for anti-Aspergillus defense. NA inhibitors might predispose individuals with severe influenza to invasive aspergillosis. These data shed light on the pathogenesis of invasive fungal infections and may identify potential therapeutic targets.
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Affiliation(s)
- Intan M.W. Dewi
- Department of Internal Medicine, Radboud University Medical Center, Nijmegen, the Netherlands
- Microbiology Division, Department of Biomedical Sciences, Faculty of Medicine, Universitas Padjadjaran, Bandung, Indonesia
| | - Cristina Cunha
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Braga, Portugal
- ICVS/3B’s – PT Government Associate Laboratory, Guimarães/Braga, Portugal
| | - Martin Jaeger
- Department of Internal Medicine, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Mark S. Gresnigt
- Department of Microbial Pathogenicity Mechanisms, Leibniz Institute for Natural Product Research and Infection Biology-Hans Knoll Institute, Jena, Germany
| | | | - Fadel M. Garishah
- Department of Internal Medicine, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Cláudio Duarte-Oliveira
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Braga, Portugal
- ICVS/3B’s – PT Government Associate Laboratory, Guimarães/Braga, Portugal
| | - Cláudia F. Campos
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Braga, Portugal
- ICVS/3B’s – PT Government Associate Laboratory, Guimarães/Braga, Portugal
| | - Lore Vanderbeke
- Department of Microbiology and Immunology, KU Leuven, Leuven, Belgium
| | | | - Roger J. Brüggemann
- Department of Pharmacy, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Paul E. Verweij
- Department of Medical Microbiology, Radboud University Medical Centre, Nijmegen, the Netherlands
| | - Katrien Lagrou
- Department of Microbiology and Immunology, KU Leuven, Leuven, Belgium
| | - Greetje Vande Velde
- Biomedical MRI/Molecular Small Animal Imaging Center, Department of Imaging and Pathology, KU Leuven, Belgium
| | - Quirijn de Mast
- Department of Internal Medicine, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Leo A.B. Joosten
- Department of Internal Medicine, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Mihai G. Netea
- Department of Internal Medicine, Radboud University Medical Center, Nijmegen, the Netherlands
| | | | - Joost Wauters
- Department of Microbiology and Immunology, KU Leuven, Leuven, Belgium
| | - Agostinho Carvalho
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Braga, Portugal
- ICVS/3B’s – PT Government Associate Laboratory, Guimarães/Braga, Portugal
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11
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Eneva R, Engibarov S, Abrashev R, Krumova E, Angelova M. Sialic acids, sialoconjugates and enzymes of their metabolism in fungi. BIOTECHNOL BIOTEC EQ 2021. [DOI: 10.1080/13102818.2021.1879678] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Affiliation(s)
- Rumyana Eneva
- Department of General Microbiology, The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, Sofia, Bulgaria
| | - Stephan Engibarov
- Department of General Microbiology, The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, Sofia, Bulgaria
| | - Radoslav Abrashev
- Department of Mycology, The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, Sofia, Bulgaria
| | - Ekaterina Krumova
- Department of Mycology, The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, Sofia, Bulgaria
| | - Maria Angelova
- Department of Mycology, The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, Sofia, Bulgaria
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12
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Exploring the Impact of Ketodeoxynonulosonic Acid in Host-Pathogen Interactions Using Uptake and Surface Display by Nontypeable Haemophilus influenzae. mBio 2021; 12:mBio.03226-20. [PMID: 33468699 PMCID: PMC7845648 DOI: 10.1128/mbio.03226-20] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
All cells in vertebrates are coated with a dense array of glycans often capped with sugars called sialic acids. Sialic acids have many functions, including serving as a signal for recognition of “self” cells by the immune system, thereby guiding an appropriate immune response against foreign “nonself” and/or damaged cells. Surface expression of the common vertebrate sialic acid (Sia) N-acetylneuraminic acid (Neu5Ac) by commensal and pathogenic microbes appears structurally to represent “molecular mimicry” of host sialoglycans, facilitating multiple mechanisms of host immune evasion. In contrast, ketodeoxynonulosonic acid (Kdn) is a more ancestral Sia also present in prokaryotic glycoconjugates that are structurally quite distinct from vertebrate sialoglycans. We detected human antibodies against Kdn-terminated glycans, and sialoglycan microarray studies found these anti-Kdn antibodies to be directed against Kdn-sialoglycans structurally similar to those on human cell surface Neu5Ac-sialoglycans. Anti-Kdn-glycan antibodies appear during infancy in a pattern similar to those generated following incorporation of the nonhuman Sia N-glycolylneuraminic acid (Neu5Gc) onto the surface of nontypeable Haemophilus influenzae (NTHi), a human commensal and opportunistic pathogen. NTHi grown in the presence of free Kdn took up and incorporated the Sia into its lipooligosaccharide (LOS). Surface display of the Kdn within NTHi LOS blunted several virulence attributes of the pathogen, including Neu5Ac-mediated resistance to complement and whole blood killing, complement C3 deposition, IgM binding, and engagement of Siglec-9. Upper airway administration of Kdn reduced NTHi infection in human-like Cmah null (Neu5Gc-deficient) mice that express a Neu5Ac-rich sialome. We propose a mechanism for the induction of anti-Kdn antibodies in humans, suggesting that Kdn could be a natural and/or therapeutic “Trojan horse” that impairs colonization and virulence phenotypes of free Neu5Ac-assimilating human pathogens.
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13
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Abrashev R, Krumova E, Petrova P, Eneva R, Kostadinova N, Miteva-Staleva J, Engibarov S, Stoyancheva G, Gocheva Y, Kolyovska V, Dishliyska V, Spassova B, Angelova M. Distribution of a novel enzyme of sialidase family among native filamentous fungi. Fungal Biol 2021; 125:412-425. [PMID: 33910682 DOI: 10.1016/j.funbio.2020.12.006] [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: 08/29/2020] [Revised: 11/18/2020] [Accepted: 12/23/2020] [Indexed: 11/25/2022]
Abstract
Sialidases (neuraminidases, EC 3.2.1.18) are widely distributed in biological systems but there are only scarce data on its production by filamentous fungi. The aim of this study was to obtain information about sialidase distribution in filamentous fungi from non-clinical isolates, to determine availability of sialidase gene, and to select a perspective producer. A total of 113 fungal strains belonging to Ascomycota and Zygomycota compassing 21 genera and 51 species were screened. Among them, 77 strains (11 orders, 14 families and 16 genera) were able to synthesize sialidase. Present data showed a habitat-dependent variation of sialidase activity between species and within species, depending on location. Sialidase gene was identified in sialidase-positive and sialidase-negative strains. . Among three perspective strains, the best producer was chosen based on their sialidase production depending on type of cultivation, medium composition, and growth temperature. The selected P. griseofulvum Р29 was cultivated in 3L bioreactor at 20 °C on medium supplemented with 0.5% milk whey. The results demonstrated better growth and 2.3-fold higher maximum enzyme activity compared to the shaken flask cultures. Moreover, the early occurring maximum (48 h) is an important prerequisite for future up scaling of the process.
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Affiliation(s)
- Radoslav Abrashev
- The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, Academician G. Bonchev 26, 1113, Sofia, Bulgaria
| | - Ekaterina Krumova
- The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, Academician G. Bonchev 26, 1113, Sofia, Bulgaria
| | - Penka Petrova
- The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, Academician G. Bonchev 26, 1113, Sofia, Bulgaria
| | - Rumyana Eneva
- The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, Academician G. Bonchev 26, 1113, Sofia, Bulgaria
| | - Nedelina Kostadinova
- The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, Academician G. Bonchev 26, 1113, Sofia, Bulgaria
| | - Jeni Miteva-Staleva
- The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, Academician G. Bonchev 26, 1113, Sofia, Bulgaria
| | - Stephan Engibarov
- The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, Academician G. Bonchev 26, 1113, Sofia, Bulgaria
| | - Galina Stoyancheva
- The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, Academician G. Bonchev 26, 1113, Sofia, Bulgaria
| | - Yana Gocheva
- The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, Academician G. Bonchev 26, 1113, Sofia, Bulgaria
| | - Vera Kolyovska
- Institute of Experimental Morphology, Pathology and Anthropology with Museum, Bulgarian Academy of Sciences, Academician G. Bonchev 25, 1113 Sofia, Bulgaria
| | - Vladislava Dishliyska
- The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, Academician G. Bonchev 26, 1113, Sofia, Bulgaria
| | - Boryana Spassova
- The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, Academician G. Bonchev 26, 1113, Sofia, Bulgaria
| | - Maria Angelova
- The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, Academician G. Bonchev 26, 1113, Sofia, Bulgaria.
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14
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Nejatie A, Akintola O, Steves E, Shamsi Kazem Abadi S, Moore MM, Bennet AJ. Structurally homologous sialidases exhibit a commonality in reactivity: Glycoside hydrolase-catalyzed hydrolysis of Kdn-thioglycosides. Bioorg Chem 2020; 106:104484. [PMID: 33268005 DOI: 10.1016/j.bioorg.2020.104484] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2020] [Revised: 10/19/2020] [Accepted: 11/16/2020] [Indexed: 10/23/2022]
Abstract
Aspergillus fumigatus is one of the main causative agents of invasive aspergillosis, an often-lethal fungal disease that affects immunocompromised individuals. A. fumigatus produces a sialidase that cleaves the nine-carbon carbohydrate Kdn from glycoconjugates. This enzyme plays a critical role in A. fumigatus pathogenicity, and is thus a target for the development of new therapeutics. In order to understand the reactivity of this Kdnase, and to develop a sensitive and selective assay for its catalytic activity we determined whether, like its close structural homolog the excreted sialidase produced by Micromonospora viridifaciens, this enzyme can efficiently hydrolyze thioglycoside substrates. We synthesized a panel of seven aryl 2-thio-d-glycero-α-d-galacto-non-2-ulopyranosonides and measured the activity of the A. fumigatus Kdnase towards these substrates. Four of these substrates were hydrolyzed by the A. fumigatus enzyme, although M. viridifaciens sialidase-catalyzed the hydrolysis of these Kdn thioglycosides with higher catalytic efficiencies (kcat/Km). We also tested an enzyme that was evolved from MvNA to improve its activity against Kdn glycosides (Glycobiology 2020, 30, 325). All three enzymes catalyzed the hydrolysis of the four most reactive Kdn thioglycosides and their second-order rate constants (kcat/Km) display a concave downwards Brønsted plot. The kinetic data, for each enzyme, is consistent with a change in rate-limiting step from CS bond cleavage for thioglycosides in which the pKa of the corresponding aryl thiol is >3.6, to a non-chemical step, which is likely a conformational change, that occurs prior to CS bond cleavage for the 2,3,4,5,6-pentafluorothiophenyl glycoside.
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Affiliation(s)
- Ali Nejatie
- Department of Chemistry, Simon Fraser University, 8888 University Drive, Burnaby V5A 1S6, Canada
| | - Oluwafemi Akintola
- Department of Chemistry, Simon Fraser University, 8888 University Drive, Burnaby V5A 1S6, Canada
| | - Elizabeth Steves
- Department of Biological Sciences, Simon Fraser University, 8888 University Drive, Burnaby V5A 1S6, Canada
| | - Saeideh Shamsi Kazem Abadi
- Department of Molecular Biology and Biochemistry, Simon Fraser University, 8888 University Drive, Burnaby V5A 1S6, Canada
| | - Margo M Moore
- Department of Biological Sciences, Simon Fraser University, 8888 University Drive, Burnaby V5A 1S6, Canada
| | - Andrew J Bennet
- Department of Chemistry, Simon Fraser University, 8888 University Drive, Burnaby V5A 1S6, Canada.
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15
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Identification of novel fish sialidase genes responsible for KDN-cleaving activity. Glycoconj J 2020; 37:745-753. [PMID: 32980954 DOI: 10.1007/s10719-020-09948-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2020] [Revised: 09/04/2020] [Accepted: 09/18/2020] [Indexed: 10/23/2022]
Abstract
2-keto-3-deoxy-D-glycero-D-galacto-nononic acid (KDN) is a minor component of sialic acids detected in vertebrates, such as human cancer cells, rat liver, and fish tissues. Although the enzyme activity of KDN-cleaving sialidase (KDN-sialidase) has been detected in rainbow trout, the gene responsible for its expression has not been identified in vertebrates. We evaluated sialidases in human and various fish for their KDN-cleaving activity using an artificial substrate, methylumbelliferyl-KDN (MU-KDN). Four of the human sialidases tested (NEU1, NEU2, NEU3, and NEU4) did not hydrolyze MU-KDN. Although most fish Neu1s showed negligible KDN-sialidase activity, two Neu1b sialidases from Oreochromis niloticus and Astyanax mexicanus, a paralog of Neu1, exhibited a potent KDN-sialidase activity. Further, O. niloticus and Oryzias latipes Neu3a exhibited a drastically high KDN-sialidase activity, while Danio rerio Neu3.1 showed moderate activities and other Neu3 proteins exhibited little activity. All the Neu4 sialidases tested in fish cleaved KDN and Neu5Ac from MU-KDN and MU-Neu5Ac, respectively, with equivalent potential. To our knowledge, this is the first report to identify KDN-sialidase genes in vertebrates and we believe that KDN-sialidase activity could be conserved among fish Neu4s.
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16
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Iwaki Y, Matsunaga E, Takegawa K, Sato C, Kitajima K. Identification and characterization of a novel, versatile sialidase from a Sphingobacterium that can hydrolyze the glycosides of any sialic acid species at neutral pH. Biochem Biophys Res Commun 2020; 523:487-492. [PMID: 31889533 DOI: 10.1016/j.bbrc.2019.12.079] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Accepted: 12/17/2019] [Indexed: 11/25/2022]
Abstract
Bacterial sialidases are widely used to remove sialic acid (Sia) residues from glycans. Most of them cleave the glycosides of N-acetylneuraminic acid (Neu5Ac) and N-glycolylneuraminic acid (Neu5Gc) under acidic pHs; however, currently available bacterial sialidases had no activity to the glycosides of deaminoneuraminic acid (Kdn). In this study, we found a novel sialidase from Sphingobacterium sp. strain HMA12 that could cleave any of the glycosides of Neu5Ac, Neu5Gc, and Kdn. It also had a broad linkage specificity, i.e., α2,3-, α2,6-, α2,8-, and α2,9-linkages, and the optimal pH at neutral ranges, pH 6.5-7.0. These properties are particularly important when sialidases are applied for in vivo digestion of the cell surface sialosides under physiological conditions. Interestingly, 2,3-didehydro-2-deoxy-N-acetylneuraminic acid (Neu5Ac2en), which is a transition state analog-based inhibitor, competitively inhibited the enzyme-catalyzed reaction for Kdn as well as for Neu5Ac, suggesting that the active site is common to the Neu5Ac and Kdn residues. Taken together, this sialidase is versatile and useful for the in vivo research on sialo-glycoconjugates.
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Affiliation(s)
- Yuya Iwaki
- Bioscience and Biotechnology Center, Nagoya University, Nagoya, 464-8601, Japan; Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, 464-8601, Japan; Program for Leading Graduate Schools, Integrative Graduate Education and Research Program in Green Natural Sciences, Nagoya University, Nagoya, 464-8601, Japan
| | - Emiko Matsunaga
- Department of Bioscience and Biotechnology, Faculty of Agriculture, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka, 819-0395, Japan
| | - Kaoru Takegawa
- Department of Bioscience and Biotechnology, Faculty of Agriculture, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka, 819-0395, Japan
| | - Chihiro Sato
- Bioscience and Biotechnology Center, Nagoya University, Nagoya, 464-8601, Japan; Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, 464-8601, Japan; Program for Leading Graduate Schools, Integrative Graduate Education and Research Program in Green Natural Sciences, Nagoya University, Nagoya, 464-8601, Japan
| | - Ken Kitajima
- Bioscience and Biotechnology Center, Nagoya University, Nagoya, 464-8601, Japan; Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, 464-8601, Japan; Program for Leading Graduate Schools, Integrative Graduate Education and Research Program in Green Natural Sciences, Nagoya University, Nagoya, 464-8601, Japan.
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17
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Shamsi Kazem Abadi S, Deen MC, Watson JN, Shidmoossavee FS, Bennet AJ. Directed evolution of a remarkably efficient Kdnase from a bacterial neuraminidase. Glycobiology 2019; 30:325-333. [DOI: 10.1093/glycob/cwz099] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Revised: 11/19/2019] [Accepted: 11/19/2019] [Indexed: 11/12/2022] Open
Abstract
AbstractN-acetylneuraminic acid (5-acetamido-3,5-dideoxy-d-glycero-d-galacto-non-2-ulosonic acid), which is the principal sialic acid family member of the non-2-ulosonic acids and their various derivatives, is often found at the terminal position on the glycan chains that adorn all vertebrate cells. This terminal position combined with subtle variations in structure and linkage to the underlying glycan chains between humans and other mammals points to the importance of this diverse group of nine-carbon sugars as indicators of the unique aspects of human evolution and is relevant to understanding an array of human conditions. Enzymes that catalyze the removal N-acetylneuraminic acid from glycoconjugates are called neuraminidases. However, despite their documented role in numerous diseases, due to the promiscuous activity of many neuraminidases, our knowledge of the functions and metabolism of many sialic acids and the effect of the attachment to cellular glycans is limited. To this end, through a concerted effort of generation of random and site-directed mutagenesis libraries, subsequent screens and positive and negative evolutionary selection protocols, we succeeded in identifying three enzyme variants of the neuraminidase from the soil bacterium Micromonospora viridifaciens with markedly altered specificity for the hydrolysis of natural Kdn (3-deoxy-d-glycero-d-galacto-non-2-ulosonic acid) glycosidic linkages compared to those of N-acetylneuraminic acid. These variants catalyze the hydrolysis of Kdn-containing disaccharides with catalytic efficiencies (second-order rate constants: kcat/Km) of greater than 105 M−1 s−1; the best variant displayed an efficiency of >106 M−1 s−1 at its optimal pH.
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Affiliation(s)
- Saeideh Shamsi Kazem Abadi
- Department of Molecular Biology and Biochemistry, Simon Fraser University, 8888 University Drive, Burnaby, British Columbia V5A 1S6, Canada
| | - Matthew C Deen
- Department of Chemistry, Simon Fraser University, 8888 University Drive, Burnaby, British Columbia V5A 1S6, Canada
| | - Jacqueline N Watson
- Department of Molecular Biology and Biochemistry, Simon Fraser University, 8888 University Drive, Burnaby, British Columbia V5A 1S6, Canada
| | - Fahimeh S Shidmoossavee
- Department of Chemistry, Simon Fraser University, 8888 University Drive, Burnaby, British Columbia V5A 1S6, Canada
| | - Andrew J Bennet
- Department of Chemistry, Simon Fraser University, 8888 University Drive, Burnaby, British Columbia V5A 1S6, Canada
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18
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Sharaf A, Oborník M, Hammad A, El-Afifi S, Marei E. Characterization and comparative genomic analysis of virulent and temperate Bacillus megaterium bacteriophages. PeerJ 2018; 6:e5687. [PMID: 30581654 PMCID: PMC6292376 DOI: 10.7717/peerj.5687] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Accepted: 09/03/2018] [Indexed: 11/20/2022] Open
Abstract
Next-Generation Sequencing (NGS) technologies provide unique possibilities for the comprehensive assessment of the environmental diversity of bacteriophages. Several Bacillus bacteriophages have been isolated, but very few Bacillus megaterium bacteriophages have been characterized. In this study, we describe the biological characteristics, whole genome sequences, and annotations for two new isolates of the B. megaterium bacteriophages (BM5 and BM10), which were isolated from Egyptian soil samples. Growth analyses indicated that the phages BM5 and BM10 have a shorter latent period (25 and 30 min, respectively) and a smaller burst size (103 and 117 PFU, respectively), in comparison to what is typical for Bacillus phages. The genome sizes of the phages BM5 and BM10 were 165,031 bp and 165,213 bp, respectively, with modular organization. Bioinformatic analyses of these genomes enabled the assignment of putative functions to 97 and 65 putative ORFs, respectively. Comparative analysis of the BM5 and BM10 genome structures, in conjunction with other B. megaterium bacteriophages, revealed relatively high levels of sequence and organizational identity. Both genomic comparisons and phylogenetic analyses support the conclusion that the sequenced phages (BM5 and BM10) belong to different sub-clusters (L5 and L7, respectively), within the L-cluster, and display different lifestyles (lysogenic and lytic, respectively). Moreover, sequenced phages encode proteins associated with Bacillus pathogenesis. In addition, BM5 does not contain any tRNA sequences, whereas BM10 genome codes for 17 tRNAs.
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Affiliation(s)
- Abdoallah Sharaf
- Genetic Department, Faculty of Agriculture, Ain Shams University, Cairo, Egypt.,Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Miroslav Oborník
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice, Czech Republic.,Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic
| | - Adel Hammad
- Department of Microbiology, Faculty of Agriculture, Minia University, Minia, Egypt
| | - Sohair El-Afifi
- Department of Agricultural Microbiology, Virology Laboratory, Ain Shams University, Cairo, Egypt
| | - Eman Marei
- Department of Agricultural Microbiology, Virology Laboratory, Ain Shams University, Cairo, Egypt
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19
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Nesbitt JR, Steves EY, Schonhofer CR, Cait A, Manku SS, Yeung JHF, Bennet AJ, McNagny KM, Choy JC, Hughes MR, Moore MM. The Aspergillus fumigatus Sialidase (Kdnase) Contributes to Cell Wall Integrity and Virulence in Amphotericin B-Treated Mice. Front Microbiol 2018; 8:2706. [PMID: 29403452 PMCID: PMC5778107 DOI: 10.3389/fmicb.2017.02706] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Accepted: 12/29/2017] [Indexed: 12/02/2022] Open
Abstract
Aspergillus fumigatus is a filamentous fungus that can cause a life-threatening invasive pulmonary aspergillosis (IPA) in immunocompromised individuals. We previously characterized an exo-sialidase from A. fumigatus that prefers the sialic acid substrate, 2-keto-3-deoxy-D-glycero-D-galacto-nononic acid (Kdn); hence it is a Kdnase. Sialidases are known virulence factors in other pathogens; therefore, the goal of our study was to evaluate the importance of Kdnase in A. fumigatus. A kdnase knockout strain (Δkdnase) was unable to grow on medium containing Kdn and displayed reduced growth and abnormal morphology. Δkdnase was more sensitive than wild type to hyperosmotic conditions and the antifungal agent, amphotericin B. In contrast, Δkdnase had increased resistance to nikkomycin, Congo Red and Calcofluor White indicating activation of compensatory cell wall chitin deposition. Increased cell wall thickness and chitin content in Δkdnase were confirmed by electron and immunofluorescence microscopy. In a neutropenic mouse model of invasive aspergillosis, the Δkdnase strain had attenuated virulence and a significantly lower lung fungal burden but only in animals that received liposomal amphotericin B after spore exposure. Macrophage numbers were almost twofold higher in lung sections from mice that received the Δkdnase strain, possibly related to higher survival of macrophages that internalized the Δkdnase conidia. Thus, A. fumigatus Kdnase is important for fungal cell wall integrity and virulence, and because Kdnase is not present in the host, it may represent a potential target for the development of novel antifungal agents.
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Affiliation(s)
- Jason R Nesbitt
- Department of Biological Sciences and the Centre for Cell Biology, Development and Disease, Simon Fraser University, Burnaby, BC, Canada
| | - Elizabeth Y Steves
- Department of Biological Sciences and the Centre for Cell Biology, Development and Disease, Simon Fraser University, Burnaby, BC, Canada
| | - Cole R Schonhofer
- Department of Biological Sciences and the Centre for Cell Biology, Development and Disease, Simon Fraser University, Burnaby, BC, Canada
| | - Alissa Cait
- Biomedical Research Centre, The University of British Columbia, Vancouver, BC, Canada
| | - Sukhbir S Manku
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, BC, Canada
| | - Juliana H F Yeung
- Department of Biological Sciences and the Centre for Cell Biology, Development and Disease, Simon Fraser University, Burnaby, BC, Canada
| | - Andrew J Bennet
- Department of Chemistry, Simon Fraser University, Burnaby, BC, Canada
| | - Kelly M McNagny
- Biomedical Research Centre, The University of British Columbia, Vancouver, BC, Canada
| | - Jonathan C Choy
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, BC, Canada
| | - Michael R Hughes
- Biomedical Research Centre, The University of British Columbia, Vancouver, BC, Canada
| | - Margo M Moore
- Department of Biological Sciences and the Centre for Cell Biology, Development and Disease, Simon Fraser University, Burnaby, BC, Canada
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20
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Khazaei K, Yeung JH, Moore MM, Bennet AJ. Inhibitory efficiencies for mechanism-based inactivators of sialidases. CAN J CHEM 2015. [DOI: 10.1139/cjc-2015-0245] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Here we describe the measurement of the inactivation rate constants for the mechanism-based inactivator 2,3-difluorosialic acid acting upon the sialidase from Micromonospora viridifaciens. Using double mixing stopped-flow experiments conducted in a 3-(N-morpholino)propanesulfonic acid buffer (100 mmol/L, pH 7.00) at 25 °C, the derived kinetic parameters are kinact/Ki = (3.9 ± 0.8) × 106 (mol/L)–1 s–1 and Ki = 1.7 ± 0.4 μmol/L. We demonstrate that the inhibitory efficiency of the inactivation event is similar to the catalytic efficiency for this sialidase acting upon a typical substrate, 4-methylumbelliferone α-d-sialoside, kcat/Km = (7.2 ± 2.8) × 106 (mol/L)–1 s–1. Furthermore, we show that the catalytic efficiencies for inactivation and hydrolysis by the Kdnase from Aspergillus fumigatus are similar for the corresponding Kdn-analogues. We conclude that the deactivating effect of incorporating an axial 3-fluoro substituent onto the sialic acid scaffold is comparable to the enhanced activation that occurs when the 4-methylumbelliferone leaving group is changed to the more nucleofugal fluoride ion.
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Affiliation(s)
- Kobra Khazaei
- Department of Chemistry, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada
| | - Juliana H.F. Yeung
- Department of Biological Sciences, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada
| | - Margo M. Moore
- Department of Biological Sciences, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada
| | - Andrew J. Bennet
- Department of Chemistry, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada
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21
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Lee Y, Ryu YB, Youn HS, Cho JK, Kim YM, Park JY, Lee WS, Park KH, Eom SH. Structural basis of sialidase in complex with geranylated flavonoids as potent natural inhibitors. ACTA CRYSTALLOGRAPHICA. SECTION D, BIOLOGICAL CRYSTALLOGRAPHY 2014; 70:1357-65. [PMID: 24816104 PMCID: PMC4014123 DOI: 10.1107/s1399004714002971] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/06/2013] [Accepted: 02/10/2014] [Indexed: 11/10/2022]
Abstract
Sialidase catalyzes the removal of a terminal sialic acid from glycoconjugates and plays a pivotal role in nutrition, cellular interactions and pathogenesis mediating various infectious diseases including cholera, influenza and sepsis. An array of antiviral sialidase agents have been developed and are commercially available, such as zanamivir and oseltamivir for treating influenza. However, the development of bacterial sialidase inhibitors has been much less successful. Here, natural polyphenolic geranylated flavonoids which show significant inhibitory effects against Cp-NanI, a sialidase from Clostridium perfringens, are reported. This bacterium causes various gastrointestinal diseases. The crystal structure of the Cp-NanI catalytic domain in complex with the best inhibitor, diplacone, is also presented. This structure explains how diplacone generates a stable enzyme-inhibitor complex. These results provide a structural framework for understanding the interaction between sialidase and natural flavonoids, which are promising scaffolds on which to discover new anti-sialidase agents.
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Affiliation(s)
- Youngjin Lee
- School of Life Sciences, Gwangju Institute of Science and Technology (GIST), Buk-gu, Gwangju 500-712, Republic of Korea
- Steitz Center for Structural Biology, Gwangju Institute of Science and Technology (GIST), Buk-gu, Gwangju 500-712, Republic of Korea
| | - Young Bae Ryu
- Infection Control Research Center, Korea Research Institute of Bioscience and Biotechnology, Jeongeup 580-185, Republic of Korea
| | - Hyung-Seop Youn
- School of Life Sciences, Gwangju Institute of Science and Technology (GIST), Buk-gu, Gwangju 500-712, Republic of Korea
- Steitz Center for Structural Biology, Gwangju Institute of Science and Technology (GIST), Buk-gu, Gwangju 500-712, Republic of Korea
| | - Jung Keun Cho
- Division of Applied Life Science (BK21 Program, IALS), Graduate School of Gyeongsang National University, Jinju 660-701, Republic of Korea
| | - Young Min Kim
- Infection Control Research Center, Korea Research Institute of Bioscience and Biotechnology, Jeongeup 580-185, Republic of Korea
| | - Ji-Young Park
- Infection Control Research Center, Korea Research Institute of Bioscience and Biotechnology, Jeongeup 580-185, Republic of Korea
| | - Woo Song Lee
- Infection Control Research Center, Korea Research Institute of Bioscience and Biotechnology, Jeongeup 580-185, Republic of Korea
| | - Ki Hun Park
- Division of Applied Life Science (BK21 Program, IALS), Graduate School of Gyeongsang National University, Jinju 660-701, Republic of Korea
| | - Soo Hyun Eom
- School of Life Sciences, Gwangju Institute of Science and Technology (GIST), Buk-gu, Gwangju 500-712, Republic of Korea
- Steitz Center for Structural Biology, Gwangju Institute of Science and Technology (GIST), Buk-gu, Gwangju 500-712, Republic of Korea
- Department of Chemistry, Gwangju Institute of Science and Technology (GIST), Buk-gu, Gwangju 500-712, Republic of Korea
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22
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Jongkees SAK, Yoo H, Withers SG. Mechanistic investigations of unsaturated glucuronyl hydrolase from Clostridium perfringens. J Biol Chem 2014; 289:11385-11395. [PMID: 24573682 DOI: 10.1074/jbc.m113.545293] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Experiments were carried out to probe the details of the hydration-initiated hydrolysis catalyzed by the Clostridium perfringens unsaturated glucuronyl hydrolase of glycoside hydrolase family 88 in the CAZy classification system. Direct (1)H NMR monitoring of the enzymatic reaction detected no accumulated reaction intermediates in solution, suggesting that rearrangement of the initial hydration product occurs on-enzyme. An attempt at mechanism-based trapping of on-enzyme intermediates using a 1,1-difluoro-substrate was unsuccessful because the probe was too deactivated to be turned over by the enzyme. Kinetic isotope effects arising from deuterium-for-hydrogen substitution at carbons 1 and 4 provide evidence for separate first-irreversible and overall rate-determining steps in the hydration reaction, with two potential mechanisms proposed to explain these results. Based on the positioning of catalytic residues in the enzyme active site, the lack of efficient turnover of a 2-deoxy-2-fluoro-substrate, and several unsuccessful attempts at confirmation of a simpler mechanism involving a covalent glycosyl-enzyme intermediate, the most plausible mechanism is one involving an intermediate bearing an epoxide on carbons 1 and 2.
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Affiliation(s)
- Seino A K Jongkees
- Departments of Chemistry and Biochemistry, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
| | - Hayoung Yoo
- Departments of Chemistry and Biochemistry, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
| | - Stephen G Withers
- Departments of Chemistry and Biochemistry, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada.
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23
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Yeung JHF, Telford JC, Shidmoossavee FS, Bennet AJ, Taylor GL, Moore MM. Kinetic and Structural Evaluation of Selected Active Site Mutants of the Aspergillus fumigatus KDNase (Sialidase). Biochemistry 2013; 52:9177-86. [DOI: 10.1021/bi401166f] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Affiliation(s)
| | | | | | | | - Garry L. Taylor
- BSRC, University of St Andrews, St Andrews, Fife KY16 9ST, U.K
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von Grafenstein S, Wallnoefer HG, Kirchmair J, Fuchs JE, Huber RG, Schmidtke M, Sauerbrei A, Rollinger JM, Liedl KR. Interface dynamics explain assembly dependency of influenza neuraminidase catalytic activity. J Biomol Struct Dyn 2013; 33:104-20. [PMID: 24279589 PMCID: PMC4226318 DOI: 10.1080/07391102.2013.855142] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2013] [Accepted: 10/04/2013] [Indexed: 12/11/2022]
Abstract
Influenza virus neuraminidase (iNA) is a homotetrameric surface protein of the influenza virus and an established target for antiviral drugs. In contrast to neuraminidases (NAs) of other biological systems (non-iNAs), enzymatic activity of iNA is only observed in a quaternary assembly and iNA needs the tetramerization to mediate enzymatic activity. Obviously, differences on a molecular level between iNA and non-iNAs are responsible for this intriguing observation. Comparison between protein structures and multiple sequence alignment allow the identification of differences in amino acid composition in crucial regions of the enzyme, such as next to the conserved D151 and the 150-loop. These differences in amino acid sequence and protein tetramerization are likely to alter the dynamics of the system. Therefore, we performed molecular dynamics simulations to investigate differences in the molecular flexibility of monomers, dimers, and tetramers of iNAs of subtype N1 (avian 2004, pandemic 1918 and pandemic 2009 iNA) and as comparison the non-iNA monomer from Clostridium perfringens. We show that conformational transitions of iNA are crucially influenced by its assembly state. The protein-protein interface induces a complex hydrogen-bonding network between the 110-helix and the 150-loop, which consequently stabilizes the structural arrangement of the binding site. Therefore, we claim that these altered dynamics are responsible for the dependence of iNA's catalytic activity on the tetrameric assembly. Only the tetramerization-induced balance between stabilization and altered local flexibility in the binding site provides the appropriate arrangement of key residues for iNA's catalytic activity.
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Affiliation(s)
- Susanne von Grafenstein
- Institute of General, Inorganic and Theoretical Chemistry and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innsbruck, Austria
| | - Hannes G. Wallnoefer
- Institute of General, Inorganic and Theoretical Chemistry and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innsbruck, Austria
| | - Johannes Kirchmair
- Department of Chemistry, Unilever Centre for Molecular Sciences Informatics, University of Cambridge, Cambridge, UK
| | - Julian E. Fuchs
- Institute of General, Inorganic and Theoretical Chemistry and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innsbruck, Austria
| | - Roland G. Huber
- Institute of General, Inorganic and Theoretical Chemistry and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innsbruck, Austria
| | - Michaela Schmidtke
- Department of Virology and Antiviral Therapy, Jena University Hospital, Jena, Germany
| | - Andreas Sauerbrei
- Department of Virology and Antiviral Therapy, Jena University Hospital, Jena, Germany
| | - Judith M. Rollinger
- Institute of Pharmacy, Pharmacognosy and CMBI, University of Innsbruck, Innsbruck, Austria
| | - Klaus R. Liedl
- Institute of General, Inorganic and Theoretical Chemistry and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innsbruck, Austria
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25
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Hopkins AP, Hawkhead JA, Thomas GH. Transport and catabolism of the sialic acids N-glycolylneuraminic acid and 3-keto-3-deoxy-D-glycero-D-galactonononic acid by Escherichia coli K-12. FEMS Microbiol Lett 2013; 347:14-22. [PMID: 23848303 DOI: 10.1111/1574-6968.12213] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2013] [Revised: 06/21/2013] [Accepted: 07/05/2013] [Indexed: 11/29/2022] Open
Abstract
Escherichia coli can transport and catabolize the common sialic acid, N-acetylneuraminic acid (Neu5Ac), as a sole source of carbon and nitrogen, which is an important mucus-derived carbon source in the mammalian gut. Herein we demonstrate that E. coli can also grow efficiently on the related sialic acids, N-glycolylneuraminic acid (Neu5Gc) and 3-keto-3-deoxy-D-glycero-D-galactonononic acid (KDN), which are transported via the sialic acid transporter NanT and catabolized using the sialic acid aldolase NanA. Catabolism of Neu5Gc uses the same pathway as Neu5Ac, likely producing glycolate instead and acetate during its breakdown and catabolism of KDN requires NanA activity, while other components of the Neu5Ac catabolism pathway are non-essential. We also demonstrate that these two sialic acids can support growth of an E. coli ∆nanT strain expressing sialic acid transporters from two bacterial pathogens, namely the tripartite ATP-independent periplasmic transporter SiaPQM from Haemophilus influenzae and the sodium solute symport transporter STM1128 from Salmonella enterica ssp. Typhimurium, suggesting that the ability to use Neu5Gc and KDN in addition to Neu5Ac is present in a number of human pathogens.
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Affiliation(s)
- Adam P Hopkins
- Department of Biology, University of York, Heslington, York, UK
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26
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Abstract
Cell surface expression of sialic acid has been reported to decrease during immune cell activation, but the significance and regulation of this phenomenon are still being investigated. The major human bacterial pathogen Streptococcus pneumoniae causes pneumonia, sepsis and meningitis, often accompanied by strong inflammatory responses. S. pneumoniae expresses a sialidase (NanA) that contributes to mucosal colonization, platelet clearance, and blood-brain barrier penetration. Using wild-type and isogenic NanA-deficient mutant strains, we showed that S. pneumoniae NanA can desialylate the surface of human THP-1 monocytes, leading to increased ERK phosphorylation, NF-κB activation, and proinflammatory cytokine release. S. pneumoniae NanA expression also stimulates interleukin-8 release and extracellular trap formation from human neutrophils. A mechanistic contribution of unmasking of inhibitory Siglec-5 from cis sialic acid interactions to the proinflammatory effect of NanA is suggested by decreased SHP-2 recruitment to the Siglec-5 intracellular domain and RNA interference studies. Finally, NanA increased production of proinflammatory cytokines in a murine intranasal challenge model of S. pneumoniae pneumonia. Importance Sialic acids decorate the surface of all mammalian cells and play important roles in physiology, development, and evolution. Siglecs are sialic acid-binding receptors on the surface of immune cells, many of which engage in cis interactions with host sialoglycan ligands and dampen inflammatory responses through transduction of inhibitory signals. Recently, certain bacterial pathogens have been shown to suppress leukocyte innate immune responses by molecular mimicry of host sialic acid structures and engagement of inhibitory Siglecs. Our present work shows that the converse can be true, i.e., that a microbial sialic acid-cleaving enzyme can induce proinflammatory responses, which are in part mediated by unmasking of an inhibitory Siglec. We conclude that host leukocytes are poised to detect and respond to microbial sialidase activity with exaggerated inflammatory responses, which could be beneficial or detrimental to the host depending on the site, stage and magnitude of infection. Sialic acids decorate the surface of all mammalian cells and play important roles in physiology, development, and evolution. Siglecs are sialic acid-binding receptors on the surface of immune cells, many of which engage in cis interactions with host sialoglycan ligands and dampen inflammatory responses through transduction of inhibitory signals. Recently, certain bacterial pathogens have been shown to suppress leukocyte innate immune responses by molecular mimicry of host sialic acid structures and engagement of inhibitory Siglecs. Our present work shows that the converse can be true, i.e., that a microbial sialic acid-cleaving enzyme can induce proinflammatory responses, which are in part mediated by unmasking of an inhibitory Siglec. We conclude that host leukocytes are poised to detect and respond to microbial sialidase activity with exaggerated inflammatory responses, which could be beneficial or detrimental to the host depending on the site, stage and magnitude of infection.
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