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Wang LL, Huang SJ, Zhao JT, Liu JY, Xiang MJ. Regulatory role of Mss11 in Candida glabrata virulence: adhesion and biofilm formation. Front Cell Infect Microbiol 2024; 13:1321094. [PMID: 38239503 PMCID: PMC10794409 DOI: 10.3389/fcimb.2023.1321094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Accepted: 12/11/2023] [Indexed: 01/22/2024] Open
Abstract
Introduction Candida glabrata has emerged as a fungal pathogen with high infection and mortality rates, and its primary virulence factors are related to adhesion and biofilm formation. These virulence factors in C.glabrata are primarily mediated by epithelial adhesins (Epas), most of which are encoded in subtelomeric regions and regulated by subtelomeric silencing mechanisms. The transcription factor Mss11, known for its regulatory role in adhesion, biofilm formation, and filamentous growth in Saccharomyces cerevisiae and Candida albicans, has also been implicated in the expression of EPA6, suggesting its potential influence on C.glabrata virulence. The present study aims to determine the regulatory role of Mss11 in the virulence of C. glabrata. Methods In this work, a Δmss11 null mutant and its complemented strain were constructed from a C.glabrata standard strain. The impact of the transcription factor Mss11 on the virulence of C.glabrata was investigated through a series of phenotypic experiments, including the microbial adhesion to hydrocarbons (MATH) test, adherence assay, biofilm assay, scanning electron microscopy and Galleria mellonella virulence assay. Furthermore, transcriptome sequencing, quantitative reverse transcription polymerase chain reaction (RT-qPCR), and chromatin immunoprecipitation sequencing (ChIP-seq) were employed to investigate the molecular mechanisms behind the regulation of Mss11. Results In C.glabrata, the loss of MSS11 led to a significant reduction in several virulence factors including cell surface hydrophobicity, epithelial cell adhesion, and biofilm formation. These observations were consistent with the decreased virulence of the Δmss11 mutant observed in the Galleria mellonella infection model. Further exploration demonstrated that Mss11 modulates C. glabrata virulence by regulating EPA1 and EPA6 expression. It binds to the upstream regions of EPA1 and EPA6, as well as the promoter regions of the subtelomeric silencing-related genes SIR4, RIF1, and RAP1, indicating the dual regulatory role of Mss11. Conclusion Mss11 plays a crucial role in C. glabrata adhesion and biofilm formation, and thus has a broad influence on virulence. This regulation is achieved by regulating the expression of EPA1 and EPA6 through both promoter-specific regulation and subtelomeric silencing.
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Affiliation(s)
- Lu-Ling Wang
- Department of Laboratory Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Department of Laboratory Medicine, Ruijin Hospital Luwan Branch, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Si-Jia Huang
- Department of Laboratory Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Department of Laboratory Medicine, Ruijin Hospital Luwan Branch, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Jun-Tao Zhao
- Department of Laboratory Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Jin-Yan Liu
- Department of Laboratory Medicine, Ruijin Hospital Luwan Branch, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Ming-Jie Xiang
- Department of Laboratory Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Department of Laboratory Medicine, Ruijin Hospital Luwan Branch, Shanghai Jiao Tong University School of Medicine, Shanghai, China
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Virulence Factors of Candida spp. and Host Immune Response Important in the Pathogenesis of Vulvovaginal Candidiasis. Int J Mol Sci 2022; 23:ijms23115895. [PMID: 35682581 PMCID: PMC9179972 DOI: 10.3390/ijms23115895] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Revised: 05/13/2022] [Accepted: 05/23/2022] [Indexed: 12/28/2022] Open
Abstract
Vulvovaginal candidiasis (VVC) is one of the most common types of vaginal infections in women around the world and is often underestimated by both patients and doctors. Research on the pathogenesis of fungal vaginal infections over the last 20 years has resulted in a closer understanding of the virulence factors involved in Candida epithelial invasion and their mechanisms of action. Recently, attention was drawn to the enormous complexity of the interaction between yeast-like fungi and host cells, as well as the level of complexity of the host's response to infection and their impact on the course and treatment of VVC. Our work provides a broad description of already known and some new reports on Candida virulence factors (such as phenotypic switching or biofilm formation capacity) and their importance for tissue invasion in VVC. At the same time, we also focus on interactions with host cells and local innate immune mechanisms involved in the response to vaginal fungal invasion that are now considered equally important in this case. The presented review describes the most important aspects of the still unknown pathogenicity of Candida associated with vaginal infections.
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García-Carnero LC, Martínez-Álvarez JA. Virulence Factors of Sporothrix schenckii. J Fungi (Basel) 2022; 8:jof8030318. [PMID: 35330320 PMCID: PMC8949611 DOI: 10.3390/jof8030318] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Revised: 03/16/2022] [Accepted: 03/17/2022] [Indexed: 12/03/2022] Open
Abstract
Sporothrix schenckii is one of the etiological agents of sporotrichosis. In this review, we discuss the virulence factors that have been proven to participate in the S. schenckii-host interaction. Among these known factors, we can find cell wall glycoproteins, adhesins, melanin, extracellular vesicles, and dimorphism. Furthermore, the morphological transition of S. schenckii in response to environmental conditions such as pH and temperature represents a means by which the fungus is able to establish mycosis in mammals. One of the key features in the development of sporotrichosis is the adhesion of the fungus to the host extracellular matrix. This event represents the first step to developing the mycosis, which involves adhesins such as the glycoproteins Gp70, Hsp60, and Pap1, which play a key role during the infection. The production of melanin helps the fungus to survive longer in the tissues and to neutralize or diminish many of the host’s attacks, which is why it is also considered a key factor in pathogenesis. Today, the study of human fungal pathogens’ virulence factors is a thriving area of research. Although we know some of the virulence factors in S. schenckii, much remains to be understood about the complex process of sporotrichosis development and the factors involved during the infection.
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A novel class of Candida glabrata cell wall proteins with β-helix fold mediates adhesion in clinical isolates. PLoS Pathog 2021; 17:e1009980. [PMID: 34962966 PMCID: PMC8746771 DOI: 10.1371/journal.ppat.1009980] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2021] [Revised: 01/10/2022] [Accepted: 11/30/2021] [Indexed: 11/19/2022] Open
Abstract
Candida glabrata is an opportunistic pathogenic yeast frequently causing infections in humans. Though it lacks typical virulence factors such as hyphal development, C. glabrata contains a remarkably large and diverse set of putative wall adhesins that is crucial for its success as pathogen. Here, we present an analysis of putative adhesins from the homology clusters V and VI. First, sequence similarity network analysis revealed relationships between cluster V and VI adhesins and S. cerevisiae haze protective factors (Hpf). Crystal structures of A-regions from cluster VI adhesins Awp1 and Awp3b reveal a parallel right-handed β-helix domain that is linked to a C-terminal β-sandwich. Structure solution of the A-region of Awp3b via single wavelength anomalous diffraction phasing revealed the largest known lanthanide cluster with 21 Gd3+ ions. Awp1-A and Awp3b-A show structural similarity to pectate lyases but binding to neither carbohydrates nor Ca2+ was observed. Phenotypic analysis of awp1Δ, awp3Δ, and awp1,3Δ double mutants did also not confirm their role as adhesins. In contrast, deletion mutants of the cluster V adhesin Awp2 in the hyperadhesive clinical isolate PEU382 demonstrated its importance for adhesion to polystyrene or glass, biofilm formation, cell aggregation and other cell surface-related phenotypes. Together with cluster III and VII adhesins our study shows that C. glabrata CBS138 can rely on a set of 42 Awp1-related adhesins with β-helix/α-crystallin domain architecture for modifying the surface characteristics of its cell wall. Adhesion to host cells and abiotic, often hydrophobic surfaces, e.g. that of medical equipment like catheters, is an indispensable virulence factor for many pathogenic fungi. Among the latter, the yeast Candida glabrata excels by encoding in its genome large sets of surface-exposed cell wall proteins. Here, we show that in the clinical isolate PEU382 of C. glabrata, hyper-adhesiveness to plastics and the tendency to biofilm formation is conferred by a single adhesin, Awp2. An integrative bioinformatic and structural analysis of this and the related Awp1 and Awp3 adhesins unifies four, so far separately assigned Awp clusters—III, V, VI and VII–into one consisting of 42 Awp1-related adhesins. These adhesins commonly present an N-terminal module consisting of a right-handed β-helix and an α-crystallin domain on the yeast surface and use a calcium-independent mode for adhesion. Their sheer number contrasts to the 20 members of the well characterized Epa and 7 members of the Pwp family of surface proteins. Given these findings we suggest that C. glabrata utilizes just two structurally distinct motifs for colonizing different host niches by adhesion: the β-helix/α-crystallin module of Awp1-related adhesins and the C-type lectin PA14-domain for Epa and Pwp proteins.
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Willaert RG, Kayacan Y, Devreese B. The Flo Adhesin Family. Pathogens 2021; 10:pathogens10111397. [PMID: 34832553 PMCID: PMC8621652 DOI: 10.3390/pathogens10111397] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Revised: 10/11/2021] [Accepted: 10/25/2021] [Indexed: 12/14/2022] Open
Abstract
The first step in the infection of fungal pathogens in humans is the adhesion of the pathogen to host tissue cells or abiotic surfaces such as catheters and implants. One of the main players involved in this are the expressed cell wall adhesins. Here, we review the Flo adhesin family and their involvement in the adhesion of these yeasts during human infections. Firstly, we redefined the Flo adhesin family based on the domain architectures that are present in the Flo adhesins and their functions, and set up a new classification of Flo adhesins. Next, the structure, function, and adhesion mechanisms of the Flo adhesins whose structure has been solved are discussed in detail. Finally, we identified from Pfam database datamining yeasts that could express Flo adhesins and are encountered in human infections and their adhesin architectures. These yeasts are discussed in relation to their adhesion characteristics and involvement in infections.
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Affiliation(s)
- Ronnie G. Willaert
- Research Group Structural Biology Brussels (SBB), Vrije Universiteit Brussel (VUB), 1050 Brussels, Belgium;
- Alliance Research Group VUB-UGent NanoMicrobiology (NAMI), 1050 Brussels, Belgium;
- International Joint Research Group VUB-EPFL NanoBiotechnology & NanoMedicine (NANO), Vrije Universiteit Brussel (VUB), 1050 Brussels, Belgium
- Correspondence: ; Tel.: +32-2629-1846
| | - Yeseren Kayacan
- Research Group Structural Biology Brussels (SBB), Vrije Universiteit Brussel (VUB), 1050 Brussels, Belgium;
- Alliance Research Group VUB-UGent NanoMicrobiology (NAMI), 1050 Brussels, Belgium;
- International Joint Research Group VUB-EPFL NanoBiotechnology & NanoMedicine (NANO), Vrije Universiteit Brussel (VUB), 1050 Brussels, Belgium
- Ecole Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland
| | - Bart Devreese
- Alliance Research Group VUB-UGent NanoMicrobiology (NAMI), 1050 Brussels, Belgium;
- International Joint Research Group VUB-EPFL NanoBiotechnology & NanoMedicine (NANO), Vrije Universiteit Brussel (VUB), 1050 Brussels, Belgium
- Ecole Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland
- Laboratory for Microbiology, Gent University (UGent), 9000 Gent, Belgium
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Satala D, Satala G, Zawrotniak M, Kozik A. Candida albicans and Candida glabrata triosephosphate isomerase - a moonlighting protein that can be exposed on the candidal cell surface and bind to human extracellular matrix proteins. BMC Microbiol 2021; 21:199. [PMID: 34210257 PMCID: PMC8252264 DOI: 10.1186/s12866-021-02235-w] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Accepted: 05/17/2021] [Indexed: 12/23/2022] Open
Abstract
Background Triosephosphate isomerase (Tpi1) is a glycolytic enzyme that has recently been reported also to be an atypical proteinaceous component of the Candida yeast cell wall. Similar to other known candidal “moonlighting proteins”, surface-exposed Tpi1 is likely to contribute to fungal adhesion during the colonization and infection of a human host. The aim of our present study was to directly prove the presence of Tpi1 on C. albicans and C. glabrata cells under various growth conditions and characterize the interactions of native Tpi1, isolated and purified from the candidal cell wall, with human extracellular matrix proteins. Results Surface plasmon resonance measurements were used to determine the dissociation constants for the complexes of Tpi1 with host proteins and these values were found to fall within a relatively narrow range of 10− 8-10− 7 M. Using a chemical cross-linking method, two motifs of the Tpi1 molecule (aa 4–17 and aa 224–247) were identified to be directly involved in the interaction with vitronectin. A proposed structural model for Tpi1 confirmed that these interaction sites were at a considerable distance from the catalytic active site. Synthetic peptides with these sequences significantly inhibited Tpi1 binding to several extracellular matrix proteins suggesting that a common region on the surface of Tpi1 molecule is involved in the interactions with the host proteins. Conclusions The current study provided structural insights into the interactions of human extracellular matrix proteins with Tpi1 that can occur at the cell surface of Candida yeasts and contribute to the host infection by these fungal pathogens. Supplementary Information The online version contains supplementary material available at 10.1186/s12866-021-02235-w.
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Affiliation(s)
- Dorota Satala
- Department of Analytical Biochemistry, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University in Krakow, Kraków, Poland
| | - Grzegorz Satala
- Department of Medicinal Chemistry, Maj Institute of Pharmacology, Polish Academy of Sciences, Kraków, Poland
| | - Marcin Zawrotniak
- Department of Comparative Biochemistry and Bioanalytics, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University in Krakow, Kraków, Poland
| | - Andrzej Kozik
- Department of Analytical Biochemistry, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University in Krakow, Kraków, Poland. .,Department of Analytical Biochemistry, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University in Krakow, Gronostajowa 7, 30-384, Krakow, Poland.
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7
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Essen LO, Vogt MS, Mösch HU. Diversity of GPI-anchored fungal adhesins. Biol Chem 2021; 401:1389-1405. [PMID: 33035180 DOI: 10.1515/hsz-2020-0199] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Accepted: 09/21/2020] [Indexed: 12/28/2022]
Abstract
Selective adhesion of fungal cells to one another and to foreign surfaces is fundamental for the development of multicellular growth forms and the successful colonization of substrates and host organisms. Accordingly, fungi possess diverse cell wall-associated adhesins, mostly large glycoproteins, which present N-terminal adhesion domains at the cell surface for ligand recognition and binding. In order to function as robust adhesins, these glycoproteins must be covalently linkedto the cell wall via C-terminal glycosylphosphatidylinositol (GPI) anchors by transglycosylation. In this review, we summarize the current knowledge on the structural and functional diversity of so far characterized protein families of adhesion domains and set it into a broad context by an in-depth bioinformatics analysis using sequence similarity networks. In addition, we discuss possible mechanisms for the membrane-to-cell wall transfer of fungal adhesins by membrane-anchored Dfg5 transglycosidases.
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Affiliation(s)
- Lars-Oliver Essen
- Department of Biochemistry, Faculty of Chemistry, Philipps-Universität Marburg, Hans-Meerwein-Straße 4, D-35043Marburg, Germany.,Center for Synthetic Microbiology, Philipps-Universität Marburg, Karl-von-Frisch-Str. 6, D-35043Marburg, Germany
| | - Marian Samuel Vogt
- Department of Biochemistry, Faculty of Chemistry, Philipps-Universität Marburg, Hans-Meerwein-Straße 4, D-35043Marburg, Germany
| | - Hans-Ulrich Mösch
- Department of Genetics, Philipps-Universität Marburg, Karl-von-Frisch-Str. 8, D-35043Marburg, Germany.,Center for Synthetic Microbiology, Philipps-Universität Marburg, Karl-von-Frisch-Str. 6, D-35043Marburg, Germany
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8
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Martin H, Somers T, Dwyer M, Robson R, Pfeffer FM, Bjornsson R, Krämer T, Kavanagh K, Velasco-Torrijos T. Scaffold diversity for enhanced activity of glycosylated inhibitors of fungal adhesion. RSC Med Chem 2020; 11:1386-1401. [PMID: 34095846 DOI: 10.1039/d0md00224k] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Accepted: 08/11/2020] [Indexed: 12/20/2022] Open
Abstract
Candida albicans is one of the most prevalent fungal pathogens involved in hospital acquired infections. It binds to glycans at the surface of epithelial cells and initiates infection. This process can be blocked by synthetic carbohydrates that mimic the structure of cell surface glycans. Herein we report the evaluation of a series of divalent glycosides featuring aromatic (benzene, squaramide) and bicyclic aliphatic (norbornene) scaffolds, with the latter being the first examples of their kind as small molecule anti-adhesion glycoconjugates. Galactosides 1 and 6, built on an aromatic core, were most efficient inhibitors of adhesion of C. albicans to buccal epithelial cells, displacing up to 36% and 48%, respectively, of yeast already attached to epithelial cells at 138 μM. Remarkably, cis-endo-norbornene 21 performed comparably to benzene-core derivatives. Conformational analysis reveals a preference for compounds 1 and 21 to adopt folded conformations. These results highlight the potential of norbornenes as a new class of aliphatic scaffolds for the synthesis of anti-adhesion compounds.
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Affiliation(s)
- Harlei Martin
- Department of Chemistry, Maynooth University Maynooth Co. Kildare Ireland
| | - Tara Somers
- Department of Biology, Maynooth University Maynooth Co. Kildare Ireland
| | - Mathew Dwyer
- Department of Biology, Maynooth University Maynooth Co. Kildare Ireland
| | - Ryan Robson
- School of Life and Environmental Sciences, Deakin University Geelong Victoria 3217 Australia
| | - Frederick M Pfeffer
- School of Life and Environmental Sciences, Deakin University Geelong Victoria 3217 Australia
| | - Ragnar Bjornsson
- Department of Inorganic Spectroscopy, Max Planck Institute for Chemical Energy Conversion Stiftstrasse 34-36 45470 Mülheim an der Ruhr Germany
| | - Tobias Krämer
- Department of Chemistry, Maynooth University Maynooth Co. Kildare Ireland .,The Hamilton Institute, Maynooth University Maynooth Co. Kildare Ireland
| | - Kevin Kavanagh
- Department of Biology, Maynooth University Maynooth Co. Kildare Ireland.,The Kathleen Lonsdale Institute for Human Health Research, Maynooth University Maynooth Co. Kildare Ireland
| | - Trinidad Velasco-Torrijos
- Department of Chemistry, Maynooth University Maynooth Co. Kildare Ireland .,The Kathleen Lonsdale Institute for Human Health Research, Maynooth University Maynooth Co. Kildare Ireland
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9
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Hoffmann D, Diderrich R, Reithofer V, Friederichs S, Kock M, Essen LO, Mösch HU. Functional reprogramming of Candida glabrata epithelial adhesins: the role of conserved and variable structural motifs in ligand binding. J Biol Chem 2020; 295:12512-12524. [PMID: 32669365 DOI: 10.1074/jbc.ra120.013968] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Revised: 07/10/2020] [Indexed: 12/11/2022] Open
Abstract
For host-cell interaction, the human fungal pathogen Candida glabrata harbors a large family of more than 20 cell wall-attached epithelial adhesins (Epas). Epa family members are lectins with binding pockets containing several conserved and variable structural hot spots, which were implicated in mediating functional diversity. In this study, we have performed an elaborate structure-based mutational analysis of numerous Epa paralogs to generally determine the role of diverse structural hot spots in conferring host cell binding and ligand binding specificity. Our study reveals that several conserved structural motifs contribute to efficient host cell binding. Moreover, our directed motif exchange experiments reveal that the variable loop CBL2 is key for programming ligand binding specificity, albeit with limited predictability. In contrast, we find that the variable loop L1 affects host cell binding without significantly influencing the specificity of ligand binding. Our data strongly suggest that variation of numerous structural hot spots in the ligand binding pocket of Epa proteins is a main driver of their functional diversification and evolution.
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Affiliation(s)
- Daniel Hoffmann
- Department of Genetics, Philipps-Universität, Marburg, Germany
| | - Rike Diderrich
- Department of Genetics, Philipps-Universität, Marburg, Germany
| | | | | | - Michael Kock
- Department of Biochemistry, Philipps-Universität, Marburg, Germany
| | - Lars-Oliver Essen
- Department of Biochemistry, Philipps-Universität, Marburg, Germany .,Center for Synthetic Microbiology, Philipps-Universität, Marburg, Germany
| | - Hans-Ulrich Mösch
- Department of Genetics, Philipps-Universität, Marburg, Germany .,Center for Synthetic Microbiology, Philipps-Universität, Marburg, Germany
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Vance TDR, Guo S, Assaie-Ardakany S, Conroy B, Davies PL. Structure and functional analysis of a bacterial adhesin sugar-binding domain. PLoS One 2019; 14:e0220045. [PMID: 31335890 PMCID: PMC6650083 DOI: 10.1371/journal.pone.0220045] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Accepted: 07/08/2019] [Indexed: 01/17/2023] Open
Abstract
Bacterial adhesins attach their hosts to surfaces through one or more ligand-binding domains. In RTX adhesins, which are localized to the outer membrane of many Gram-negative bacteria via the type I secretion system, we see several examples of a putative sugar-binding domain. Here we have recombinantly expressed one such ~20-kDa domain from the ~340-kDa adhesin found in Marinobacter hydrocarbonoclasticus, an oil-degrading bacterium. The sugar-binding domain was purified from E. coli with a yield of 100 mg/L of culture. Circular dichroism analysis showed that the protein was rich in beta-structure, was moderately heat resistant, and required Ca2+ for proper folding. A crystal structure was obtained in Ca2+ at 1.2-Å resolution, which showed the presence of three Ca2+ ions, two of which were needed for structural integrity and one for binding sugars. Glucose was soaked into the crystal, where it bound to the sugar's two vicinal hydroxyl groups attached to the first and second (C1 and C2) carbons in the pyranose ring. This attraction to glucose caused the protein to bind certain polysaccharide-based column matrices and was used in a simple competitive binding assay to assess the relative affinity of sugars for the protein's ligand-binding site. Fucose, glucose and N-acetylglucosamine bound most tightly, and N-acetylgalactosamine hardly bound at all. Isothermal titration calorimetry was used to determine specific binding affinities, which lie in the 100-μM range. Glycan arrays were tested to expand the range of ligand sugars assayed, and showed that MhPA14 bound preferentially to branched polymers containing terminal sugars highlighted as strong binders in the competitive binding assay. Some of these binders have vicinal hydroxyl groups attached to the C3 and C4 carbons that are sterically equivalent to those presented by the C1 and C2 carbons of glucose.
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Affiliation(s)
- Tyler D. R. Vance
- Department of Biomedical and Molecular Science, Queen’s University, Kingston, Ontario, Canada
| | - Shuaiqi Guo
- Department of Biomedical and Molecular Science, Queen’s University, Kingston, Ontario, Canada
| | - Shayan Assaie-Ardakany
- Department of Biomedical and Molecular Science, Queen’s University, Kingston, Ontario, Canada
| | - Brigid Conroy
- Department of Biomedical and Molecular Science, Queen’s University, Kingston, Ontario, Canada
| | - Peter L. Davies
- Department of Biomedical and Molecular Science, Queen’s University, Kingston, Ontario, Canada
- * E-mail:
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11
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Grinberg IR, Yaniv O, de Ora LO, Muñoz-Gutiérrez I, Hershko A, Livnah O, Bayer EA, Borovok I, Frolow F, Lamed R, Voronov-Goldman M. Distinctive ligand-binding specificities of tandem PA14 biomass-sensory elements from Clostridium thermocellum and Clostridium clariflavum. Proteins 2019; 87:917-930. [PMID: 31162722 PMCID: PMC6852018 DOI: 10.1002/prot.25753] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2019] [Revised: 05/26/2019] [Accepted: 05/30/2019] [Indexed: 11/25/2022]
Abstract
Cellulolytic clostridia use a highly efficient cellulosome system to degrade polysaccharides. To regulate genes encoding enzymes of the multi‐enzyme cellulosome complex, certain clostridia contain alternative sigma I (σI) factors that have cognate membrane‐associated anti‐σI factors (RsgIs) which act as polysaccharide sensors. In this work, we analyzed the structure‐function relationship of the extracellular sensory elements of Clostridium (Ruminiclostridium) thermocellum and Clostridium clariflavum (RsgI3 and RsgI4, respectively). These elements were selected for comparison, as each comprised two tandem PA14‐superfamily motifs. The X‐ray structures of the PA14 modular dyads from the two bacterial species were determined, both of which showed a high degree of structural and sequence similarity, although their binding preferences differed. Bioinformatic approaches indicated that the DNA sequence of promoter of sigI/rsgI operons represents a strong signature, which helps to differentiate binding specificity of the structurally similar modules. The σI4‐dependent C. clariflavum promoter sequence correlates with binding of RsgI4_PA14 to xylan and was identified in genes encoding xylanases, whereas the σI3‐dependent C. thermocellum promoter sequence correlates with RsgI3_PA14 binding to pectin and regulates pectin degradation‐related genes. Structural similarity between clostridial PA14 dyads to PA14‐containing proteins in yeast helped identify another crucial signature element: the calcium‐binding loop 2 (CBL2), which governs binding specificity. Variations in the five amino acids that constitute this loop distinguish the pectin vs xylan specificities. We propose that the first module (PA14A) is dominant in directing the binding to the ligand in both bacteria. The two X‐ray structures of the different PA14 dyads represent the first reported structures of tandem PA14 modules.
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Affiliation(s)
- Inna Rozman Grinberg
- Department of Molecular Microbiology and Biotechnology, Tel Aviv University, Tel Aviv, Israel.,Department of Biochemistry and Biophysics, Stockholm University, Stockholm, Sweden
| | - Oren Yaniv
- Department of Molecular Microbiology and Biotechnology, Tel Aviv University, Tel Aviv, Israel
| | - Lizett Ortiz de Ora
- Department of Molecular Microbiology and Biotechnology, Tel Aviv University, Tel Aviv, Israel.,Department of Chemistry, University of California, Irvine, California
| | - Iván Muñoz-Gutiérrez
- Department of Biomolecular Sciences, The Weizmann Institute of Science, Rehovot, Israel.,Outreach Research Training and Minority Science Programs, School of Biological Sciences, University of California, Irvine, California
| | - Almog Hershko
- Department of Molecular Microbiology and Biotechnology, Tel Aviv University, Tel Aviv, Israel
| | - Oded Livnah
- Department of Biological Chemistry, The Alexander Silberman Institute of Life Sciences, The Wolfson Centre for Applied Structural Biology, The Hebrew University of Jerusalem, The Edmond J. Safra Campus, Jerusalem, Israel
| | - Edward A Bayer
- Department of Biomolecular Sciences, The Weizmann Institute of Science, Rehovot, Israel
| | - Ilya Borovok
- Department of Molecular Microbiology and Biotechnology, Tel Aviv University, Tel Aviv, Israel
| | - Felix Frolow
- Department of Molecular Microbiology and Biotechnology, Tel Aviv University, Tel Aviv, Israel
| | - Raphael Lamed
- Department of Molecular Microbiology and Biotechnology, Tel Aviv University, Tel Aviv, Israel
| | - Milana Voronov-Goldman
- Department of Molecular Microbiology and Biotechnology, Tel Aviv University, Tel Aviv, Israel
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Kock M, Brückner S, Wozniak N, Maestre-Reyna M, Veelders M, Schlereth J, Mösch HU, Essen LO. Structural and Functional Characterization of PA14/Flo5-Like Adhesins From Komagataella pastoris. Front Microbiol 2018; 9:2581. [PMID: 30425696 PMCID: PMC6218569 DOI: 10.3389/fmicb.2018.02581] [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: 07/07/2018] [Accepted: 10/10/2018] [Indexed: 12/19/2022] Open
Abstract
Cell–cell and cell-substrate based adhesion of yeasts are major determinants of their adoption of different life styles. Genome-mining of ascomycetous GPI-anchored cell wall proteins with lectin-like PA14 domains identified a unique class of putative adhesins in the clade of methylotrophic Komagataella yeasts, many of which are known to colonize plants and insects involving yet unknown adhesion mechanisms. Here, we report the functional and structural analysis of two of its members: KpFlo1 (=Cea1), that is highly specific for terminal N-acetylglucosamine moieties, and KpFlo2, which represents an orphan lectin with intact binding site but unknown specificity. Crystal structures of the Cea1 adhesion domain complexed to N-acetylglucosamine and N,N′-diacetylchitobiose reveal a Ca2+-dependent binding mode that differs from other members of the PA14/Flo5 adhesin family. Heterologous expression of Cea1A in Saccharomyces cerevisiae promotes cellular adhesion to non-reducing ends of non-crystalline chitin. Overall, our data suggest that high-affinity recognition of β-GlcNAc-capped glycans by Cea1 enable Komagataella species to interact with surface cues present in fungi and insects.
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Affiliation(s)
- Michael Kock
- Department of Biochemistry, Faculty of Chemistry, Philipps University of Marburg, Marburg, Germany
| | - Stefan Brückner
- Department of Genetics, Faculty of Biology, Philipps University of Marburg, Marburg, Germany
| | - Nina Wozniak
- Department of Genetics, Faculty of Biology, Philipps University of Marburg, Marburg, Germany
| | | | - Maik Veelders
- Department of Biochemistry, Faculty of Chemistry, Philipps University of Marburg, Marburg, Germany
| | - Julia Schlereth
- Department of Biochemistry, Faculty of Chemistry, Philipps University of Marburg, Marburg, Germany
| | - Hans-Ulrich Mösch
- Department of Genetics, Faculty of Biology, Philipps University of Marburg, Marburg, Germany.,LOEWE Center for Synthetic Microbiology, Philipps University of Marburg, Marburg, Germany
| | - Lars-Oliver Essen
- Department of Biochemistry, Faculty of Chemistry, Philipps University of Marburg, Marburg, Germany.,LOEWE Center for Synthetic Microbiology, Philipps University of Marburg, Marburg, Germany
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Willaert RG. Adhesins of Yeasts: Protein Structure and Interactions. J Fungi (Basel) 2018; 4:jof4040119. [PMID: 30373267 PMCID: PMC6308950 DOI: 10.3390/jof4040119] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2018] [Revised: 10/23/2018] [Accepted: 10/24/2018] [Indexed: 12/14/2022] Open
Abstract
The ability of yeast cells to adhere to other cells or substrates is crucial for many yeasts. The budding yeast Saccharomyces cerevisiae can switch from a unicellular lifestyle to a multicellular one. A crucial step in multicellular lifestyle adaptation is self-recognition, self-interaction, and adhesion to abiotic surfaces. Infectious yeast diseases such as candidiasis are initiated by the adhesion of the yeast cells to host cells. Adhesion is accomplished by adhesin proteins that are attached to the cell wall and stick out to interact with other cells or substrates. Protein structures give detailed insights into the molecular mechanism of adhesin-ligand interaction. Currently, only the structures of a very limited number of N-terminal adhesion domains of adhesins have been solved. Therefore, this review focuses on these adhesin protein families. The protein architectures, protein structures, and ligand interactions of the flocculation protein family of S. cerevisiae; the epithelial adhesion family of C. glabrata; and the agglutinin-like sequence protein family of C. albicans are reviewed and discussed.
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Affiliation(s)
- Ronnie G Willaert
- Alliance Research Group VUB-UGent NanoMicrobiology (NAMI), IJRG VUB-EPFL NanoBiotechnology & NanoMedicine (NANO), Research Group Structural Biology Brussels, Vrije Universiteit Brussel, 1050 Brussels, Belgium.
- Department Bioscience Engineering, University Antwerp, 2020 Antwerp, Belgium.
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Sharma A, Singh S, Tewari R, Bhatt V, Sharma J, Maurya I. Phytochemical analysis and mode of action against Candida glabrata of Paeonia emodi extracts. J Mycol Med 2018; 28:443-451. [DOI: 10.1016/j.mycmed.2018.04.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Revised: 04/22/2018] [Accepted: 04/27/2018] [Indexed: 01/26/2023]
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15
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Timmermans B, De Las Peñas A, Castaño I, Van Dijck P. Adhesins in Candida glabrata. J Fungi (Basel) 2018; 4:E60. [PMID: 29783771 PMCID: PMC6023314 DOI: 10.3390/jof4020060] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Revised: 05/15/2018] [Accepted: 05/17/2018] [Indexed: 12/31/2022] Open
Abstract
The human fungal pathogen Candida glabrata is causing more and more problems in hospitals, as this species shows an intrinsic antifungal drug resistance or rapidly becomes resistant when challenged with antifungals. C. glabrata only grows in the yeast form, so it is lacking a yeast-to-hyphae switch, which is one of the main virulence factors of C. albicans. An important virulence factor of C. glabrata is its capacity to strongly adhere to many different substrates. To achieve this, C. glabrata expresses a large number of adhesin-encoding genes and genome comparisons with closely related species, including the non-pathogenic S. cerevisiae, which revealed a correlation between the number of adhesin-encoding genes and pathogenicity. The adhesins are involved in the first steps during an infection; they are the first point of contact with the host. For several of these adhesins, their importance in adherence to different substrates and subsequent biofilm formation was demonstrated in vitro or in vivo. In this review, we provide an overview of the role of C. glabrata adhesins during adhesion and biofilm formation both, under in vitro and in vivo conditions.
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Affiliation(s)
- Bea Timmermans
- KU Leuven, Laboratory of Molecular Cell Biology, Kasteelpark Arenberg 31 bus 2438, 3001 Leuven, Belgium.
- VIB-KU Leuven Center for Microbiology, 3001 Leuven, Belgium.
| | - Alejandro De Las Peñas
- IPICYT, División de Biología Molecular, Camino a la Presa San José 2055, C.P., San Luis Potosí 78216 San Luis Potosí, Mexico.
| | - Irene Castaño
- IPICYT, División de Biología Molecular, Camino a la Presa San José 2055, C.P., San Luis Potosí 78216 San Luis Potosí, Mexico.
| | - Patrick Van Dijck
- KU Leuven, Laboratory of Molecular Cell Biology, Kasteelpark Arenberg 31 bus 2438, 3001 Leuven, Belgium.
- VIB-KU Leuven Center for Microbiology, 3001 Leuven, Belgium.
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16
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Ghufran MS, Ghosh K, Kanade SR. A fucose specific lectin from Aspergillus flavus induced interleukin-8 expression is mediated by mitogen activated protein kinase p38. Med Mycol 2017; 55:323-333. [PMID: 27664169 DOI: 10.1093/mmy/myw066] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Accepted: 07/08/2016] [Indexed: 12/28/2022] Open
Abstract
Aspergillus flavus is an ubiquitous, opportunistic fungus responsible to cause invasive fungal allergic diseases, including bronchopulmonary invasive aspergillosis in persons with altered immune function. Lectins have been implicated as interaction mediators between the pathogenic fungi and human host. We isolated L-fucose specific lectin from A. flavus (FFL) and purified it to homogeneity with a combination of ion exchange and hydrophobic interaction chromatography methods. Its hemagglutination activity was significantly inhibited by 125 μM L-fucose as compared to other sugars and sugar derivatives. We, then used human cell line L-132, and U937 cell line to explore the possible cytotoxicity and proinflammatory effect of this fucose-specific lectin. The lectin induced the expression of proinflammatory cytokine interleukin-8 (IL-8) in a dose-dependent manner, and it was found to be associated with the p38 mitogen activated protein kinase (MAPK). The p38MAPK signalling pathway regulates the transcription factor activator protein-1 (AP-1) activity, which is the integration point of many signals that can differentially affect the expression and transcriptional activity of a cell. We observed activation of c-Jun, a critical component of the AP-1 complex, mediated by p38MAPK upon the FFL treatment in L-132 cells. Finally, inhibition of p38MAPK by a specific inhibitor attenuates the c-Jun, suggesting the p38MAPK involvement in the c-Jun activation, which in turn transcriptionally activates the induction of IL-8 in response to the lectin. Thus, this study showed a potential lectin-mediated mechanism to modulate the immune response during host-fungus interactions.
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17
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Carugo O, Blatova OA, Medrish EO, Blatov VA, Proserpio DM. Packing topology in crystals of proteins and small molecules: a comparison. Sci Rep 2017; 7:13209. [PMID: 29038549 PMCID: PMC5643379 DOI: 10.1038/s41598-017-12699-4] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Accepted: 09/13/2017] [Indexed: 12/19/2022] Open
Abstract
We compared the topologies of protein and small molecule crystals, which have many common features - both are molecular crystals with intermolecular interactions much weaker than intramolecular interactions. They also have different features - a considerably large fraction of the volume of protein crystals is occupied by liquid water while no room is available to other molecules in small molecule crystals. We analyzed the overall and local topology and performed multilevel topological analyses (with the software package ToposPro) of carefully selected high quality sets of protein and small molecule crystal structures. Given the suboptimal packing of protein crystals, which is due the special shape and size of proteins, it would be reasonable to expect that the topology of protein crystals is different from the topology of small molecule crystals. Surprisingly, we discovered that these two types of crystalline compounds have strikingly similar topologies. This might suggest that molecular crystal formations share symmetry rules independent of molecular dimension.
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Affiliation(s)
- Oliviero Carugo
- Department of Chemistry, University of Pavia, viale Taramelli 12, I-27100, Pavia, Italy.
- Department of Structural and Computational Biology, University of Vienna, Campus Vienna Biocenter 5, A-1030, Vienna, Austria.
| | - Olga A Blatova
- Samara Center for Theoretical Materials Science (SCTMS), Samara University, Ac. Pavlov St. 1, Samara, 443011, Russia
| | - Elena O Medrish
- Samara Center for Theoretical Materials Science (SCTMS), Samara University, Ac. Pavlov St. 1, Samara, 443011, Russia
| | - Vladislav A Blatov
- Samara Center for Theoretical Materials Science (SCTMS), Samara University, Ac. Pavlov St. 1, Samara, 443011, Russia.
- School of Materials Science and Engineering, Northwestern Polytechnical University, Xi'an, Shaanxi, 710072, People's Republic of China.
| | - Davide M Proserpio
- Samara Center for Theoretical Materials Science (SCTMS), Samara University, Ac. Pavlov St. 1, Samara, 443011, Russia.
- Università degli Studi di Milano, Dipartimento di Chimica, Via C. Golgi 19, 20133, Milano, Italy.
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18
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Abstract
Twenty years after their discovery, knots in proteins are now quite well understood. They are believed to be functionally advantageous and provide extra stability to protein chains. In this work, we go one step further and search for links-entangled structures, more complex than knots, which consist of several components. We derive conditions that proteins need to meet to be able to form links. We search through the entire Protein Data Bank and identify several sequentially nonhomologous chains that form a Hopf link and a Solomon link. We relate topological properties of these proteins to their function and stability and show that the link topology is characteristic of eukaryotes only. We also explain how the presence of links affects the folding pathways of proteins. Finally, we define necessary conditions to form Borromean rings in proteins and show that no structure in the Protein Data Bank forms a link of this type.
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Affiliation(s)
- Pawel Dabrowski-Tumanski
- Faculty of Chemistry, University of Warsaw, 02-093, Warsaw, Poland
- Centre of New Technologies, University of Warsaw, 02-097, Warsaw, Poland
| | - Joanna I Sulkowska
- Faculty of Chemistry, University of Warsaw, 02-093, Warsaw, Poland;
- Centre of New Technologies, University of Warsaw, 02-097, Warsaw, Poland
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19
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Pérez-Flores G, Hernández-Silva C, Gutiérrez-Escobedo G, De Las Peñas A, Castaño I, Arreola J, Pérez-Cornejo P. P2X7 from j774 murine macrophages acts as a scavenger receptor for bacteria but not yeast. Biochem Biophys Res Commun 2016; 481:19-24. [PMID: 27833023 DOI: 10.1016/j.bbrc.2016.11.027] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2016] [Accepted: 11/06/2016] [Indexed: 11/18/2022]
Abstract
We studied the effects of extracellular ATP and Ca2+ on uptake of bacteria (Staphylococcus aureus or Escherichia coli) and live yeast (Candida glabrata) by J774 macrophages to determine the role of endogenous P2X7 receptors in phagocytosis. Our findings show that phagocytosis of bio-particles coated with S. aureus or E. coli was blocked by ATP and the P2X7 receptor agonist BzATP, while yeast phagocytosis was not. A438079, an antagonist of P2X7 receptors, partially reverted the effects of ATP on bacterial phagocytosis. To determine if P2X7-mediated Ca2+ entry into macrophages was blocking the engulfment of bacteria, we measured phagocytic activity in the absence or presence of 2 mM extracellular Ca2+ with or without ATP. Ca2+, in the absence of ATP, was required for engulfment of E. coli and C. glabrata but not S. aureus. Adding ATP inhibited phagocytosis of S. aureus and E. coli regardless of Ca2+, suggesting that Ca2+ entry was not important for inhibiting phagocytosis. On the other hand, phagocytosis of normal or hyper-adherent C. glabrata mutants had an absolute requirement for extracellular Ca2+ due to yeast adhesion to macrophages mediated by Ca2+-dependent adhesion proteins. We conclude that unstimulated P2X7 from J774 cells act as scavenger receptor for the uptake of S. aureus and E. coli but not of yeast; Ca2+ entry via P2X7 receptors play no role in phagocytosis of S. aureus and E. coli; while the effect of Ca2+ on C. glabrata phagocytosis was mediated by the adhesins Epa1, Epa6 and Epa7.
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Affiliation(s)
- Gabriela Pérez-Flores
- Unidad Académica Multidisciplinaria Zona Huasteca, Universidad Autónoma de San Luis Potosí, Cd. Valles, SLP 79060, Mexico
| | - Cesar Hernández-Silva
- Department of Physiology and Biophysics, School of Medicine, Universidad Autónoma de San Luis Potosí, San Luis Potosí, SLP 78210, Mexico
| | | | | | - Irene Castaño
- División de Biología Molecular, IPICYT, San Luis Potosí, SLP 78216, Mexico
| | - Jorge Arreola
- Institute of Physics, Universidad Autónoma de San Luis Potosí, San Luis Potosí, SLP 78290, Mexico
| | - Patricia Pérez-Cornejo
- Department of Physiology and Biophysics, School of Medicine, Universidad Autónoma de San Luis Potosí, San Luis Potosí, SLP 78210, Mexico.
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20
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Lectin-Glycan Interaction Network-Based Identification of Host Receptors of Microbial Pathogenic Adhesins. mBio 2016; 7:mBio.00584-16. [PMID: 27406561 PMCID: PMC4958244 DOI: 10.1128/mbio.00584-16] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The first step in the infection of humans by microbial pathogens is their adherence to host tissue cells, which is frequently based on the binding of carbohydrate-binding proteins (lectin-like adhesins) to human cell receptors that expose glycans. In only a few cases have the human receptors of pathogenic adhesins been described. A novel strategy—based on the construction of a lectin-glycan interaction (LGI) network—to identify the potential human binding receptors for pathogenic adhesins with lectin activity was developed. The new approach is based on linking glycan array screening results of these adhesins to a human glycoprotein database via the construction of an LGI network. This strategy was used to detect human receptors for virulent Escherichia coli (FimH adhesin), and the fungal pathogens Candida albicans (Als1p and Als3p adhesins) and C. glabrata (Epa1, Epa6, and Epa7 adhesins), which cause candidiasis. This LGI network strategy allows the profiling of potential adhesin binding receptors in the host with prioritization, based on experimental binding data, of the most relevant interactions. New potential targets for the selected adhesins were predicted and experimentally confirmed. This methodology was also used to predict lectin interactions with envelope glycoproteins of human-pathogenic viruses. It was shown that this strategy was successful in revealing that the FimH adhesin has anti-HIV activity. Microbial pathogens may express a wide range of carbohydrate-specific adhesion proteins that mediate adherence to host tissues. Pathogen attachment to host cells is achieved through the binding of these lectin-like adhesins to glycans on human glycoproteins. In only a few cases have the human receptors of pathogenic adhesins been described. We developed a new strategy to predict these interacting receptors. Therefore, we developed a novel LGI network that would allow the mapping of potential adhesin binding receptors in the host with prioritization, based on the experimental binding data, of the most relevant interactions. New potential targets for the selected adhesins (bacterial uroepithelial FimH from E. coli and fungal Epa and Als adhesins from C. glabrata and C. albicans) were predicted and experimentally confirmed. This methodology was also used to predict lectin interactions with human-pathogenic viruses and to discover whether FimH adhesin has anti-HIV activity.
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21
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Lustig AJ. Hypothesis: Paralog Formation from Progenitor Proteins and Paralog Mutagenesis Spur the Rapid Evolution of Telomere Binding Proteins. Front Genet 2016; 7:10. [PMID: 26904098 PMCID: PMC4748036 DOI: 10.3389/fgene.2016.00010] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2015] [Accepted: 01/22/2016] [Indexed: 12/31/2022] Open
Abstract
Through elegant studies in fungal cells and complex organisms, we propose a unifying paradigm for the rapid evolution of telomere binding proteins (TBPs) that associate with either (or both) telomeric DNA and telomeric proteins. TBPs protect and regulate telomere structure and function. Four critical factors are involved. First, TBPs that commonly bind to telomeric DNA include the c-Myb binding proteins, OB-fold single-stranded binding proteins, and G-G base paired Hoogsteen structure (G4) binding proteins. Each contributes independently or, in some cases, cooperatively, to provide a minimum level of telomere function. As a result of these minimal requirements and the great abundance of homologs of these motifs in the proteome, DNA telomere-binding activity may be generated more easily than expected. Second, telomere dysfunction gives rise to genome instability, through the elevation of recombination rates, genome ploidy, and the frequency of gene mutations. The formation of paralogs that diverge from their progenitor proteins ultimately can form a high frequency of altered TBPs with altered functions. Third, TBPs that assemble into complexes (e.g., mammalian shelterin) derive benefits from the novel emergent functions. Fourth, a limiting factor in the evolution of TBP complexes is the formation of mutually compatible interaction surfaces amongst the TBPs. These factors may have different degrees of importance in the evolution of different phyla, illustrated by the apparently simpler telomeres in complex plants. Selective pressures that can utilize the mechanisms of paralog formation and mutagenesis to drive TBP evolution along routes dependent on the requisite physiologic changes.
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Affiliation(s)
- Arthur J Lustig
- Department of Biochemistry and Molecular Biology, Tulane University, New Orleans LA, USA
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22
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Diderrich R, Kock M, Maestre-Reyna M, Keller P, Steuber H, Rupp S, Essen LO, Mösch HU. Structural Hot Spots Determine Functional Diversity of the Candida glabrata Epithelial Adhesin Family. J Biol Chem 2015; 290:19597-613. [PMID: 26105055 PMCID: PMC4528126 DOI: 10.1074/jbc.m115.655654] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Revised: 05/20/2015] [Indexed: 11/06/2022] Open
Abstract
For host colonization, the human fungal pathogen Candida glabrata is known to utilize a large family of highly related surface-exposed cell wall proteins, the lectin-like epithelial adhesins (Epas). To reveal the structure-function relationships within the entire Epa family, we have performed a large scale functional analysis of the adhesion (A) domains of 17 Epa paralogs in combination with three-dimensional structural studies of selected members with cognate ligands. Our study shows that most EpaA domains exert lectin-like functions and together recognize a wide variety of glycans with terminal galactosides for conferring epithelial cell adhesion. We further identify several conserved and variable structural features within the diverse Epa ligand binding pockets, which affect affinity and specificity. These features rationalize why mere phylogenetic relationships within the Epa family are weak indicators for functional classification and explain how Epa-like adhesins have evolved in C. glabrata and related fungal species.
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Affiliation(s)
| | - Michael Kock
- Biochemistry, Philipps-Universität, 35043 Marburg, Germany
| | | | - Petra Keller
- the Fraunhofer-Institut für Grenzflächen und Bioverfahrenstechnik, 70569 Stuttgart, Germany, and
| | - Holger Steuber
- Biochemistry, Philipps-Universität, 35043 Marburg, Germany
| | - Steffen Rupp
- the Fraunhofer-Institut für Grenzflächen und Bioverfahrenstechnik, 70569 Stuttgart, Germany, and the Institut für Grenzflächenverfahrenstechnik und Plasmatechnologie, Universität Stuttgart, 70569 Stuttgart, Germany
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23
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Glöckner A, Cornely OA. Candida glabrata -unique features and challenges in the clinical management of invasive infections. Mycoses 2015. [DOI: 10.1111/myc.12348] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- A. Glöckner
- BDH-Klinik Greifswald GmbH; Greifswald Germany
| | - O. A. Cornely
- Department I of Internal Medicine; Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD); Clinical Trials Centre Cologne (ZKS Köln, BMBF 01KN1106) Center for Integrated Oncology (CIO Köln Bonn); German Centre for Infection Research (DZIF); University of Cologne; Cologne Germany
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24
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Molecular mechanism of flocculation self-recognition in yeast and its role in mating and survival. mBio 2015; 6:mBio.00427-15. [PMID: 25873380 PMCID: PMC4453552 DOI: 10.1128/mbio.00427-15] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
We studied the flocculation mechanism at the molecular level by determining the atomic structures of N-Flo1p and N-Lg-Flo1p in complex with their ligands. We show that they have similar ligand binding mechanisms but distinct carbohydrate specificities and affinities, which are determined by the compactness of the binding site. We characterized the glycans of Flo1p and their role in this binding process and demonstrate that glycan-glycan interactions significantly contribute to the cell-cell adhesion mechanism. Therefore, the extended flocculation mechanism is based on the self-interaction of Flo proteins and this interaction is established in two stages, involving both glycan-glycan and protein-glycan interactions. The crucial role of calcium in both types of interaction was demonstrated: Ca2+ takes part in the binding of the carbohydrate to the protein, and the glycans aggregate only in the presence of Ca2+. These results unify the generally accepted lectin hypothesis with the historically first-proposed “Ca2+-bridge” hypothesis. Additionally, a new role of cell flocculation is demonstrated; i.e., flocculation is linked to cell conjugation and mating, and survival chances consequently increase significantly by spore formation and by introduction of genetic variability. The role of Flo1p in mating was demonstrated by showing that mating efficiency is increased when cells flocculate and by differential transcriptome analysis of flocculating versus nonflocculating cells in a low-shear environment (microgravity). The results show that a multicellular clump (floc) provides a uniquely organized multicellular ultrastructure that provides a suitable microenvironment to induce and perform cell conjugation and mating. Yeast cells can form multicellular clumps under adverse growth conditions that protect cells from harsh environmental stresses. The floc formation is based on the self-interaction of Flo proteins via an N-terminal PA14 lectin domain. We have focused on the flocculation mechanism and its role. We found that carbohydrate specificity and affinity are determined by the accessibility of the binding site of the Flo proteins where the external loops in the ligand-binding domains are involved in glycan recognition specificity. We demonstrated that, in addition to the Flo lectin-glycan interaction, glycan-glycan interactions also contribute significantly to cell-cell recognition and interaction. Additionally, we show that flocculation provides a uniquely organized multicellular ultrastructure that is suitable to induce and accomplish cell mating. Therefore, flocculation is an important mechanism to enhance long-term yeast survival.
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25
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Taylor ME, Drickamer K. Convergent and divergent mechanisms of sugar recognition across kingdoms. Curr Opin Struct Biol 2014; 28:14-22. [PMID: 25102772 PMCID: PMC4444583 DOI: 10.1016/j.sbi.2014.07.003] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2014] [Revised: 06/23/2014] [Accepted: 07/16/2014] [Indexed: 12/03/2022]
Abstract
Protein modules that bind specific oligosaccharides are found across all kingdoms of life from single-celled organisms to man. Different, overlapping and evolving designations for sugar-binding domains in proteins can sometimes obscure common features that often reflect convergent solutions to the problem of distinguishing sugars with closely similar structures and binding them with sufficient affinity to achieve biologically meaningful results. Structural and functional analysis has revealed striking parallels between protein domains with widely different structures and evolutionary histories that employ common solutions to the sugar recognition problem. Recent studies also demonstrate that domains descended from common ancestors through divergent evolution appear more widely across the kingdoms of life than had previously been recognized.
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Affiliation(s)
- Maureen E Taylor
- Department of Life Sciences, Imperial College, London SW7 2AZ, United Kingdom
| | - Kurt Drickamer
- Department of Life Sciences, Imperial College, London SW7 2AZ, United Kingdom.
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26
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Ielasi FS, Verhaeghe T, Desmet T, Willaert RG. Engineering the carbohydrate-binding site of Epa1p from Candida glabrata: generation of adhesin mutants with different carbohydrate specificity. Glycobiology 2014; 24:1312-22. [DOI: 10.1093/glycob/cwu075] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
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27
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Lectins in human pathogenic fungi. Rev Iberoam Micol 2014; 31:72-5. [DOI: 10.1016/j.riam.2013.09.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2013] [Accepted: 09/27/2013] [Indexed: 11/21/2022] Open
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28
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Fungal lectins: structure, function and potential applications. Curr Opin Struct Biol 2013; 23:678-85. [DOI: 10.1016/j.sbi.2013.07.007] [Citation(s) in RCA: 91] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2013] [Revised: 06/18/2013] [Accepted: 07/11/2013] [Indexed: 11/20/2022]
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Gabaldón T, Martin T, Marcet-Houben M, Durrens P, Bolotin-Fukuhara M, Lespinet O, Arnaise S, Boisnard S, Aguileta G, Atanasova R, Bouchier C, Couloux A, Creno S, Almeida Cruz J, Devillers H, Enache-Angoulvant A, Guitard J, Jaouen L, Ma L, Marck C, Neuvéglise C, Pelletier E, Pinard A, Poulain J, Recoquillay J, Westhof E, Wincker P, Dujon B, Hennequin C, Fairhead C. Comparative genomics of emerging pathogens in the Candida glabrata clade. BMC Genomics 2013; 14:623. [PMID: 24034898 PMCID: PMC3847288 DOI: 10.1186/1471-2164-14-623] [Citation(s) in RCA: 135] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2013] [Accepted: 07/31/2013] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Candida glabrata follows C. albicans as the second or third most prevalent cause of candidemia worldwide. These two pathogenic yeasts are distantly related, C. glabrata being part of the Nakaseomyces, a group more closely related to Saccharomyces cerevisiae. Although C. glabrata was thought to be the only pathogenic Nakaseomyces, two new pathogens have recently been described within this group: C. nivariensis and C. bracarensis. To gain insight into the genomic changes underlying the emergence of virulence, we sequenced the genomes of these two, and three other non-pathogenic Nakaseomyces, and compared them to other sequenced yeasts. RESULTS Our results indicate that the two new pathogens are more closely related to the non-pathogenic N. delphensis than to C. glabrata. We uncover duplications and accelerated evolution that specifically affected genes in the lineage preceding the group containing N. delphensis and the three pathogens, which may provide clues to the higher propensity of this group to infect humans. Finally, the number of Epa-like adhesins is specifically enriched in the pathogens, particularly in C. glabrata. CONCLUSIONS Remarkably, some features thought to be the result of adaptation of C. glabrata to a pathogenic lifestyle, are present throughout the Nakaseomyces, indicating these are rather ancient adaptations to other environments. Phylogeny suggests that human pathogenesis evolved several times, independently within the clade. The expansion of the EPA gene family in pathogens establishes an evolutionary link between adhesion and virulence phenotypes. Our analyses thus shed light onto the relationships between virulence and the recent genomic changes that occurred within the Nakaseomyces. SEQUENCE ACCESSION NUMBERS Nakaseomyces delphensis: CAPT01000001 to CAPT01000179Candida bracarensis: CAPU01000001 to CAPU01000251Candida nivariensis: CAPV01000001 to CAPV01000123Candida castellii: CAPW01000001 to CAPW01000101Nakaseomyces bacillisporus: CAPX01000001 to CAPX01000186.
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Affiliation(s)
- Toni Gabaldón
- Bioinformatics and Genomics Programme, Centre for Genomic Regulation (CRG) and UPF, Doctor Aiguader, 88, Barcelona, 08003, Spain
- Comparative Genomics Group, CRG-Centre for Genomic Regulation, Doctor Aiguader, 88, Barcelona, 08003, Spain
| | - Tiphaine Martin
- Université de Bordeaux 1, LaBRI, INRIA Bordeaux Sud-Ouest (MAGNOME), Talence, F-33405, France
| | - Marina Marcet-Houben
- Bioinformatics and Genomics Programme, Centre for Genomic Regulation (CRG) and UPF, Doctor Aiguader, 88, Barcelona, 08003, Spain
| | - Pascal Durrens
- Université de Bordeaux 1, LaBRI, INRIA Bordeaux Sud-Ouest (MAGNOME), Talence, F-33405, France
| | - Monique Bolotin-Fukuhara
- Institut de Génétique et Microbiologie, UMR8621 CNRS-Université Paris Sud, Bât 400, UFR des Sciences, Orsay Cedex, F 91405, France
| | - Olivier Lespinet
- Institut de Génétique et Microbiologie, UMR8621 CNRS-Université Paris Sud, Bât 400, UFR des Sciences, Orsay Cedex, F 91405, France
| | - Sylvie Arnaise
- Institut de Génétique et Microbiologie, UMR8621 CNRS-Université Paris Sud, Bât 400, UFR des Sciences, Orsay Cedex, F 91405, France
| | - Stéphanie Boisnard
- Institut de Génétique et Microbiologie, UMR8621 CNRS-Université Paris Sud, Bât 400, UFR des Sciences, Orsay Cedex, F 91405, France
| | - Gabriela Aguileta
- Bioinformatics and Genomics Programme, Centre for Genomic Regulation (CRG) and UPF, Doctor Aiguader, 88, Barcelona, 08003, Spain
| | - Ralitsa Atanasova
- APHP, Hôpital St Antoine, Service de Parasitologie-Mycologie, and UMR S945, Inserm, Université P. M. Curie, Paris, France
| | - Christiane Bouchier
- Département Génomes et Génétique, Institut Pasteur, Plate-forme Génomique, rue du Dr. Roux, Paris, F-75015, France
| | - Arnaud Couloux
- CEA, IG, DSV, Genoscope, 2 rue Gaston Crémieux, Evry Cedex, 91057, France
| | - Sophie Creno
- Département Génomes et Génétique, Institut Pasteur, Plate-forme Génomique, rue du Dr. Roux, Paris, F-75015, France
| | - Jose Almeida Cruz
- Architecture et Réactivité de l‘ARN, Institut de Biologie Moléculaire et Cellulaire du CNRS, Université de Strasbourg, Strasbourg Cedex, F-67084, France
- Present adress: Champalimaud Foundation, Av. Brasília, Lisboa, 1400-038, Portugal
| | - Hugo Devillers
- Institut de Génétique et Microbiologie, UMR8621 CNRS-Université Paris Sud, Bât 400, UFR des Sciences, Orsay Cedex, F 91405, France
| | - Adela Enache-Angoulvant
- Institut de Génétique et Microbiologie, UMR8621 CNRS-Université Paris Sud, Bât 400, UFR des Sciences, Orsay Cedex, F 91405, France
- APHP, Hôpital Bicêtre, Service de Microbiologie, Paris, France
| | - Juliette Guitard
- APHP, Hôpital St Antoine, Service de Parasitologie-Mycologie, and UMR S945, Inserm, Université P. M. Curie, Paris, France
| | - Laure Jaouen
- Institut de Génétique et Microbiologie, UMR8621 CNRS-Université Paris Sud, Bât 400, UFR des Sciences, Orsay Cedex, F 91405, France
| | - Laurence Ma
- Département Génomes et Génétique, Institut Pasteur, Plate-forme Génomique, rue du Dr. Roux, Paris, F-75015, France
| | - Christian Marck
- Institut de biologie et technologies de Saclay (iBiTec-S), Gif-sur-Yvette cedex, 91191, France
| | | | - Eric Pelletier
- CEA, IG, DSV, Genoscope, 2 rue Gaston Crémieux, Evry Cedex, 91057, France
| | - Amélie Pinard
- Institut de Génétique et Microbiologie, UMR8621 CNRS-Université Paris Sud, Bât 400, UFR des Sciences, Orsay Cedex, F 91405, France
| | - Julie Poulain
- CEA, IG, DSV, Genoscope, 2 rue Gaston Crémieux, Evry Cedex, 91057, France
| | - Julien Recoquillay
- Institut de Génétique et Microbiologie, UMR8621 CNRS-Université Paris Sud, Bât 400, UFR des Sciences, Orsay Cedex, F 91405, France
| | - Eric Westhof
- Architecture et Réactivité de l‘ARN, Institut de Biologie Moléculaire et Cellulaire du CNRS, Université de Strasbourg, Strasbourg Cedex, F-67084, France
| | - Patrick Wincker
- CEA, IG, DSV, Genoscope, 2 rue Gaston Crémieux, Evry Cedex, 91057, France
| | - Bernard Dujon
- Institut Pasteur, Unité de Génétique moléculaires des levures, UMR3525 CNRS, UFR927, Université P. M. Curie, 25 rue du Docteur Roux, Paris Cedex15, F75724, France
| | - Christophe Hennequin
- APHP, Hôpital St Antoine, Service de Parasitologie-Mycologie, and UMR S945, Inserm, Université P. M. Curie, Paris, France
| | - Cécile Fairhead
- Institut de Génétique et Microbiologie, UMR8621 CNRS-Université Paris Sud, Bât 400, UFR des Sciences, Orsay Cedex, F 91405, France
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Ielasi FS, Goyal P, Sleutel M, Wohlkonig A, Willaert RG. The mannose-specific lectin domains of Flo1p from Saccharomyces cerevisiae and Lg-Flo1p from S. pastorianus: crystallization and preliminary X-ray diffraction analysis of the adhesin-carbohydrate complexes. Acta Crystallogr Sect F Struct Biol Cryst Commun 2013; 69:779-782. [PMID: 23832207 PMCID: PMC3702324 DOI: 10.1107/s1744309113015030] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2013] [Accepted: 05/31/2013] [Indexed: 06/02/2023]
Abstract
Flo1p and Lg-Flo1p are two cell-wall adhesins belonging to the Flo (flocculation) protein family from the yeasts Saccharomyces cerevisiae and S. pastorianus. The main function of these modular proteins endowed with calcium-dependent lectin activity is to mediate cell-cell adhesion events during yeast flocculation, a process which is well known at the cellular level but still not fully characterized from a molecular perspective. Recently, structural features of the N-terminal Flo lectin domains, including the N-terminal domain of Lg-Flo1p (N-Lg-Flo1p), and their interactions with carbohydrate molecules have been investigated. However, structural data concerning the N-terminal domain of Flo1p (N-Flo1p), which is the most specific among the Flo proteins, are missing and information about the N-Lg-Flo1p-carbohydrate interaction still lacks detailed structural insight. Here, the crystallization and preliminary X-ray characterization of the apo form and the mannose complex of N-Flo1p and X-ray analysis of N-Lg-Flo1p crystals soaked in α-1,2-mannobiose are reported. The N-Flo1p crystals diffracted to a resolution of 1.43 Å in the case of the apo form and to 2.12 Å resolution for the mannose complex. Both crystals were orthorhombic and belonged to space group P212121, with one molecule in the asymmetric unit. The N-Lg-Flo1p-α-1,2-mannobiose complex crystal diffracted to 1.73 Å resolution and belonged to the monoclinic space group P1211 with two molecules in the asymmetric unit.
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Affiliation(s)
- Francesco S Ielasi
- Structural Biology Brussels (SBB) - Department of Bioengineering Sciences, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium.
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Abstract
Understanding the pathogenesis of an infectious disease is critical for developing new methods to prevent infection and diagnose or cure disease. Adherence of microorganisms to host tissue is a prerequisite for tissue invasion and infection. Fungal cell wall adhesins involved in adherence to host tissue or abiotic medical devices are critical for colonization leading to invasion and damage of host tissue. Here, with a main focus on pathogenic Candida species, we summarize recent progress made in the field of adhesins in human fungal pathogens and underscore the importance of these proteins in establishment of fungal diseases.
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Sim L, Groes M, Olesen K, Henriksen A. Structural and biochemical characterization of theN‐terminal domain of flocculinLg‐Flo1p fromSaccharomyces pastorianusreveals a unique specificity for phosphorylated mannose. FEBS J 2013; 280:1073-83. [DOI: 10.1111/febs.12102] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2012] [Revised: 12/17/2012] [Accepted: 12/18/2012] [Indexed: 11/28/2022]
Affiliation(s)
- Lyann Sim
- The Protein Chemistry Group Carlsberg Laboratory Copenhagen Denmark
| | | | | | - Anette Henriksen
- The Protein Chemistry Group Carlsberg Laboratory Copenhagen Denmark
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Structural basis for promiscuity and specificity during Candida glabrata invasion of host epithelia. Proc Natl Acad Sci U S A 2012; 109:16864-9. [PMID: 23035251 DOI: 10.1073/pnas.1207653109] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
The human pathogenic yeast Candida glabrata harbors more than 20 surface-exposed, epithelial adhesins (Epas) for host cell adhesion. The Epa family recognizes host glycans and discriminates between target tissues by their adhesin (A) domains, but a detailed structural basis for ligand-binding specificity of Epa proteins has been lacking so far. In this study, we provide high-resolution crystal structures of the Epa1A domain in complex with different carbohydrate ligands that reveal how host cell mucin-type O-glycans are recognized and allow a structure-guided classification of the Epa family into specific subtypes. Further detailed structural and functional characterization of subtype-switched Epa1 variants shows that specificity is governed by two inner loops, CBL1 and CBL2, involved in calcium binding as well as by three outer loops, L1, L2, and L3. In summary, our study provides the structural basis for promiscuity and specificity of Epa adhesins, which might further contribute to developing anti-adhesive antimycotics and combating Candida colonization.
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