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López-Fuentes E, Gutiérrez-Escobedo G, Timmermans B, Van Dijck P, De Las Peñas A, Castaño I. Candida glabrata's Genome Plasticity Confers a Unique Pattern of Expressed Cell Wall Proteins. J Fungi (Basel) 2018; 4:jof4020067. [PMID: 29874814 PMCID: PMC6023349 DOI: 10.3390/jof4020067] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Revised: 05/29/2018] [Accepted: 06/03/2018] [Indexed: 12/19/2022] Open
Abstract
Candida glabrata is the second most common cause of candidemia, and its ability to adhere to different host cell types, to microorganisms, and to medical devices are important virulence factors. Here, we consider three characteristics that confer extraordinary advantages to C. glabrata within the host. (1) C. glabrata has a large number of genes encoding for adhesins most of which are localized at subtelomeric regions. The number and sequence of these genes varies substantially depending on the strain, indicating that C. glabrata can tolerate high genomic plasticity; (2) The largest family of CWPs (cell wall proteins) is the EPA (epithelial adhesin) family of adhesins. Epa1 is the major adhesin and mediates adherence to epithelial, endothelial and immune cells. Several layers of regulation like subtelomeric silencing, cis-acting regulatory regions, activators, nutritional signaling, and stress conditions tightly regulate the expression of many adhesin-encoding genes in C. glabrata, while many others are not expressed. Importantly, there is a connection between acquired resistance to xenobiotics and increased adherence; (3) Other subfamilies of adhesins mediate adherence to Candida albicans, allowing C. glabrata to efficiently invade the oral epithelium and form robust biofilms. It is noteworthy that every C. glabrata strain analyzed presents a unique pattern of CWPs at the cell surface.
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Affiliation(s)
- Eunice López-Fuentes
- Instituto Potosino de Investigación Científica y Tecnológica (IPICYT), División de Biología Molecular, Camino a la Presa San José 2055, San Luis Potosí, SLP 78216, Mexico.
| | - Guadalupe Gutiérrez-Escobedo
- Instituto Potosino de Investigación Científica y Tecnológica (IPICYT), División de Biología Molecular, Camino a la Presa San José 2055, San Luis Potosí, SLP 78216, Mexico.
| | - 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.
| | - 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.
| | - Alejandro De Las Peñas
- Instituto Potosino de Investigación Científica y Tecnológica (IPICYT), División de Biología Molecular, Camino a la Presa San José 2055, San Luis Potosí, SLP 78216, Mexico.
| | - Irene Castaño
- Instituto Potosino de Investigación Científica y Tecnológica (IPICYT), División de Biología Molecular, Camino a la Presa San José 2055, San Luis Potosí, SLP 78216, Mexico.
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Jamerson M, da Rocha-Azevedo B, Cabral GA, Marciano-Cabral F. Pathogenic Naegleria fowleri and non-pathogenic Naegleria lovaniensis exhibit differential adhesion to, and invasion of, extracellular matrix proteins. MICROBIOLOGY (READING, ENGLAND) 2012; 158:791-803. [PMID: 22222499 PMCID: PMC3352113 DOI: 10.1099/mic.0.055020-0] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2011] [Revised: 12/08/2011] [Accepted: 12/27/2011] [Indexed: 01/27/2023]
Abstract
Naegleria fowleri and Naegleria lovaniensis are closely related free-living amoebae found in the environment. N. fowleri causes primary amoebic meningoencephalitis (PAM), a rapidly fatal disease of the central nervous system, while N. lovaniensis is non-pathogenic. N. fowleri infection occurs when the amoebae access the nasal passages, attach to the nasal mucosa and its epithelial lining, and migrate to the brain. This process involves interaction with components of the host extracellular matrix (ECM). Since the ability to invade tissues can be a characteristic that distinguishes pathogenic from non-pathogenic amoebae, the objective of this study was to assess adhesion to, and invasion of, the ECM by these two related but distinct Naegleria species. N. fowleri exhibited a higher level of adhesion to the ECM components laminin-1, fibronectin and collagen I. Scanning electron microscopy revealed that N. fowleri attached on ECM substrata exhibited a spread-out appearance that included the presence of focal adhesion-like structures. Western immunoblotting revealed two integrin-like proteins for both species, but one of these, with a molecular mass of approximately 70 kDa, was detected at a higher level in N. fowleri. Confocal microscopy indicated that the integrin-like proteins co-localized to the focal adhesion-like structures. Furthermore, anti-integrin antibody decreased adhesion of N. fowleri to ECM components. Finally, N. fowleri disrupted 3D ECM scaffolds, while N. lovaniensis had a minimal effect. Collectively, these results indicate a distinction in adhesion to, and invasion of, ECM proteins between N. fowleri and N. lovaniensis.
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Affiliation(s)
- Melissa Jamerson
- Department of Microbiology and Immunology, Virginia Commonwealth University, School of Medicine, Richmond, VA 23298-0678, USA
| | - Bruno da Rocha-Azevedo
- Department of Microbiology and Immunology, Virginia Commonwealth University, School of Medicine, Richmond, VA 23298-0678, USA
| | - Guy A Cabral
- Department of Microbiology and Immunology, Virginia Commonwealth University, School of Medicine, Richmond, VA 23298-0678, USA
| | - Francine Marciano-Cabral
- Department of Microbiology and Immunology, Virginia Commonwealth University, School of Medicine, Richmond, VA 23298-0678, USA
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Tronchin G, Pihet M, Lopes-Bezerra LM, Bouchara JP. Adherence mechanisms in human pathogenic fungi. Med Mycol 2008; 46:749-72. [DOI: 10.1080/13693780802206435] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
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Henriques M, Azeredo J, Oliveira R. Candida species adhesion to oral epithelium: factors involved and experimental methodology used. Crit Rev Microbiol 2007; 32:217-26. [PMID: 17123906 DOI: 10.1080/10408410601023524] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Due to the increasing prevalence and emergence of Non-Candida albicans Candida (NCAC) species, especially in immunosupressed patients, it is becoming urgent to deepen the current knowledge about virulence factors of these species. Adhesion of cells to epithelium is considered one of the major virulence factors of Candida species. However, relatively little is known concerning the adhesion mechanisms of NCAC species to epithelium, as well as about the factors affecting the adhesion process. This review focuses both the mechanisms that regulate the adhesion interactions and the factors involved and the description of the experimental methodology that has been used to perform the adhesion assays.
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Affiliation(s)
- Mariana Henriques
- Centre of Biological Engineering, University of Minho, Braga, Portugal.
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Mendes-Giannini MJS, Soares CP, da Silva JLM, Andreotti PF. Interaction of pathogenic fungi with host cells: Molecular and cellular approaches. ACTA ACUST UNITED AC 2005; 45:383-94. [PMID: 16087326 DOI: 10.1016/j.femsim.2005.05.014] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2005] [Accepted: 05/27/2005] [Indexed: 11/26/2022]
Abstract
This review provides an overview of several molecular and cellular approaches that are likely to supply insights into the host-fungus interaction. Fungi present intra- and/or extracellular host-parasite interfaces, the parasitism phenomenon being dependent on complementary surface molecules. The entry of the pathogen into the host cell is initiated by the fungus adhering to the cell surface, which generates an uptake signal that may induce its cytoplasmatic internalization. Furthermore, microbial pathogens use a variety of their surface molecules to bind to host extracellular matrix (ECM) components to establish an effective infection. On the other hand, integrins mediate the tight adhesion of cells to the ECM at sites referred to as focal adhesions and also play a role in cell signaling. The phosphorylation process is an important mechanism of cell signaling and regulation; it has been implicated recently in defense strategies against a variety of pathogens that alter host-signaling pathways in order to facilitate their invasion and survival within host cells. The study of signal transduction pathways in virulent fungi is especially important in view of their putative role in the regulation of pathogenicity. This review discusses fungal adherence, changes in cytoskeletal organization and signal transduction in relation to host-fungus interaction.
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Pendrak ML, Yan SS, Roberts DD. Sensing the host environment: recognition of hemoglobin by the pathogenic yeast Candida albicans. Arch Biochem Biophys 2004; 426:148-56. [PMID: 15158665 DOI: 10.1016/j.abb.2004.02.006] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2003] [Revised: 02/06/2004] [Indexed: 01/10/2023]
Abstract
Adhesion to host cells and tissues is important for several steps in the pathogenesis of disseminated Candida albicans infections. Although such adhesion is evident in vivo and for C. albicans grown in vitro in complex medium, some adhesive activities are absent when cultures are grown in defined media. However, addition of hemoglobin to defined media restores binding and adhesion to several host proteins. This activity of hemoglobin is independent of iron acquisition and is mediated by a cell surface hemoglobin receptor. In addition to regulating expression of adhesion receptors, hemoglobin rapidly induces expression of several genes. One of these, a heme oxygenase, allows the pathogen to utilize exogenous heme or hemoglobin to acquire iron and to produce the cytoprotective molecules alpha-biliverdin and carbon monoxide. The specific recognition of and responses to hemoglobin demonstrate a unique adaptation of C. albicans to be both a commensal and an opportunistic pathogen in humans.
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Affiliation(s)
- Michael L Pendrak
- Laboratory of Pathology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892-1500, USA
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Santoni G, Lucciarini R, Amantini C, Jacobelli J, Spreghini E, Ballarini P, Piccoli M, Gismondi A. Candida albicans expresses a focal adhesion kinase-like protein that undergoes increased tyrosine phosphorylation upon yeast cell adhesion to vitronectin and the EA.hy 926 human endothelial cell line. Infect Immun 2002; 70:3804-15. [PMID: 12065524 PMCID: PMC128043 DOI: 10.1128/iai.70.7.3804-3815.2002] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The signaling pathways triggered by adherence of Candida albicans to the host cells or extracellular matrix are poorly understood. We provide here evidence in C. albicans yeasts of a p105 focal adhesion kinase (Fak)-like protein (that we termed CaFak), antigenically related to the vertebrate p125Fak, and its involvement in integrin-like-mediated fungus adhesion to vitronectin (VN) and EA.hy 926 human endothelial cell line. Biochemical analysis with different anti-chicken Fak antibodies identified CaFak as a 105-kDa protein and immunofluorescence and cytofluorimetric analysis on permeabilized cells specifically stain C. albicans yeasts; moreover, confocal microscopy evidences CaFak as a cytosolic protein that colocalizes on the membrane with the integrin-like VN receptors upon yeast adhesion to VN. The protein tyrosine kinase (PTK) inhibitors genistein and herbimycin A strongly inhibited C. albicans yeast adhesion to VN and EA.hy 926 endothelial cells. Moreover, engagement of alpha v beta 3 and alpha v beta 5 integrin-like on C. albicans either by specific monoclonal antibodies or upon adhesion to VN or EA.hy 926 endothelial cells stimulates CaFak tyrosine phosphorylation that is blocked by PTK inhibitor. A role for CaFak in C. albicans yeast adhesion was also supported by the failure of VN to stimulate its tyrosine phosphorylation in a C. albicans mutant showing normal levels of CaFak and VNR-like integrins but displaying reduced adhesiveness to VN and EA.hy 926 endothelial cells. Our results suggest that C. albicans Fak-like protein is involved in the control of yeast cell adhesion to VN and endothelial cells.
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Affiliation(s)
- Giorgio Santoni
- Department of Pharmacological Sciences and Experimental Medicine, University of Camerino, 62032 Camerino, Italy.
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Abstract
Candida species other than Candida albicans now account for up to 50% of deep candidiasis cases, yet little attention has been paid to the virulence attributes of these fungi. Adherence to host tissues, response to environmental changes and the secretion of hydrolases are all thought to be important in Candida virulence. The identification of virulence attributes unique to a particular Candida species could provide powerful insights into the pathogenic process but will require the use of genome-wide approaches such as transcript profiling, signature-tagged mutagenesis and in vivo expression technology.
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Affiliation(s)
- K Haynes
- Dept of Infectious Diseases, Faculty of Medicine, Imperial College of Science, Technology & Medicine, Du Cane Road, W12 0NN, London, UK.
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Santoni G, Spreghini E, Lucciarini R, Amantini C, Piccoli M. Involvement of alpha(v)beta3 integrin-like receptor and glycosaminoglycans in Candida albicans germ tube adhesion to vitronectin and to a human endothelial cell line. Microb Pathog 2001; 31:159-72. [PMID: 11562169 DOI: 10.1006/mpat.2001.0459] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The present study was undertaken to investigate the expression of alpha(v)beta3 and alpha(v)beta5 integrin-like vitronectin receptors (VNRs) on Candida albicans germ tube and their involvement in its adhesion to vitronectin (VN) and human endothelial cells. By immunofluorescence and FACS analysis, several monoclonal antibodies directed against human alpha(v) or beta3 integrin subunit or alpha(v)beta3 and alpha(v)beta5 heterodimers, positively stained C. albicans germ tubes. C. albicans germ tubes specifically adhered (45-50%) to VN and this adhesion was markedly inhibited by RGD-, but not RGE-containing peptides. Adhesion of C. albicans germ tubes to VN was strongly inhibited by anti-alphav, anti-beta3 or anti-alpha(v)beta3, but not by alpha(v)beta5 monoclonal antibody. C. albicans germ tube adhesion to VN was also inhibited by glycosaminoglycans (GAGs) such as heparin or chondroitin sulphate. Finally, we show that C. albicans germ tubes adhere to the human EA.hy 926 endothelial cell line. This adhesion is markedly blocked by anti-beta3 monoclonal antibody, GRGDSP peptide or heparin, and is completely abolished by their combination. Overall these results indicate that C. albicans germ tube adherence to VN and to a human endothelial cell line is mediated by alpha(v)beta3, but not by alpha(v)beta5-like integrin, and depends on GAGs which may act by regulating alpha(v)beta3 integrin-like/VN adhesive interaction.
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Affiliation(s)
- G Santoni
- Department of Pharmacological Sciences and Experimental Medicine, University of Camerino, Camerino, Italy.
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Abstract
Progress in the understanding of fungal adhesion has led to the identification of novel proteins recognizing the RGD tripeptide in matrix proteins and to the characterization of what appears to be an emerging subset of fungal adhesins that themselves contain an RGD sequence.
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Affiliation(s)
- M K Hostetter
- Yale Child Health Research Center, Yale University School of Medicine, New Haven, Connecticut 06519, USA.
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Abstract
The vertebrate integrins provide a paradigm for cell surface proteins involved in adhesion and morphogenesis. However, homologs of integrins have been found in more primitive organisms. This review will discuss the evidence for surface proteins in Candida albicans and Candida tropicalis that contain motifs reminiscent of integrins and will analyze the contributions of one of these proteins, Int1p, to adhesion, morphogenesis, and virulence. Other microorganisms thought to express integrin-like proteins will also be addressed.
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Affiliation(s)
- M K Hostetter
- Yale University School of Medicine, 464 Congress Avenue, New Haven, Connecticut 06519, USA
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Gozalbo D, Gil-Navarro I, Azorín I, Renau-Piqueras J, Martínez JP, Gil ML. The cell wall-associated glyceraldehyde-3-phosphate dehydrogenase of Candida albicans is also a fibronectin and laminin binding protein. Infect Immun 1998; 66:2052-9. [PMID: 9573088 PMCID: PMC108162 DOI: 10.1128/iai.66.5.2052-2059.1998] [Citation(s) in RCA: 178] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
By immunoelectron microscopy with a polyclonal antibody against the cytosolic glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase (GAPDH) from Candida albicans (anti-GAPDH PAb), the protein was clearly detected at the outer surface of the cell wall, particularly on blastoconidia, as well as in the cytoplasm. Intact blastoconidia were able to adhere to fibronectin and laminin immobilized on microtiter plates, and this adhesion was markedly reduced by both the anti-GAPDH PAb and soluble GAPDH from Saccharomyces cerevisiae. In addition, semiquantitative flow cytometry analysis with the anti-GAPDH PAb showed a decrease in antibody binding to cells in the presence of soluble fibronectin and laminin. Purified cytosolic C. albicans GAPDH was found to bind to fibronectin and laminin in a ligand Western blot assay. These observations suggest that the cell wall-associated form of the GAPDH in C. albicans could be involved in mediating adhesion of fungal cells to fibronectin and laminin, thus contributing to the attachment of the microorganism to host tissues and to the dissemination of Candida infection.
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Affiliation(s)
- D Gozalbo
- Departamento de Microbiología y Ecología, Facultad de Farmacia, Universitat de València, Spain
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Chaffin WL, López-Ribot JL, Casanova M, Gozalbo D, Martínez JP. Cell wall and secreted proteins of Candida albicans: identification, function, and expression. Microbiol Mol Biol Rev 1998; 62:130-80. [PMID: 9529890 PMCID: PMC98909 DOI: 10.1128/mmbr.62.1.130-180.1998] [Citation(s) in RCA: 505] [Impact Index Per Article: 19.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The cell wall is essential to nearly every aspect of the biology and pathogenicity of Candida albicans. Although it was initially considered an almost inert cellular structure that protected the protoplast against osmotic offense, more recent studies have demonstrated that it is a dynamic organelle. The major components of the cell wall are glucan and chitin, which are associated with structural rigidity, and mannoproteins. The protein component, including both mannoprotein and nonmannoproteins, comprises some 40 or more moieties. Wall proteins may differ in their expression, secretion, or topological location within the wall structure. Proteins may be modified by glycosylation (primarily addition of mannose residues), phosphorylation, and ubiquitination. Among the secreted enzymes are those that are postulated to have substrates within the cell wall and those that find substrates in the extracellular environment. Cell wall proteins have been implicated in adhesion to host tissues and ligands. Fibrinogen, complement fragments, and several extracellular matrix components are among the host proteins bound by cell wall proteins. Proteins related to the hsp70 and hsp90 families of conserved stress proteins and some glycolytic enzyme proteins are also found in the cell wall, apparently as bona fide components. In addition, the expression of some proteins is associated with the morphological growth form of the fungus and may play a role in morphogenesis. Finally, surface mannoproteins are strong immunogens that trigger and modulate the host immune response during candidiasis.
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Affiliation(s)
- W L Chaffin
- Department of Microbiology and Immunology, Texas Tech University Health Sciences Center, Lubbock 79430, USA.
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Borg-von Zepelin M, Eucker J, Rüchel R. [Involvement of secretory Candida proteinases in the adherence of C. tropicalis blastoconidia in a cell culture model]. Mycoses 1998; 40 Suppl 1:64-72. [PMID: 9417516 DOI: 10.1111/j.1439-0507.1997.tb00544.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The influence of the heterologous acid secretory Candida proteinases on the adherence of the non-proteinase secreting strain of C. tropicalis DSM 4959 to epitheloid cells (vero line) was examined. The proteinases of the following Candida strains were used: C. albicans ATCC 10261 (serotype A), C. albicans ATCC 48867 (serotype B), C. tropicalis DSM 4238. The assays were performed with the previously described in-vitro-adherence test [1] using the following principle steps: Candida proteinases and C. tropicalis blastoconidia were incubated with verocells in microtest plates in phosphate-buffer in the range of pH 4.0 to pH 7.0. Adherent Candida cells were detected according to Filler et al. [2] with anti-Candida-mannoprotein antibodies and a secondary anti-rabbit-peroxidase conjugate. Compared to controls with denaturated proteinases, the photometric evaluation of adherent C. tropicalis cells showed, under optimal conditions, an augmentation of the adherence due to the Candida proteinases of about 50%. The optimum of this adherence augmentation was in the range of pH 5.5 which is outside the general activity optimum of Candida proteinases (pH 3). The degree of purity of these proteinases had no marked influence on the adherence. The specificity of the proteinase dependent adherence augmentation could be demonstrated with the enzyme inhibitor Pepstatin A. C. tropicalis blastoconidia supplemented by pepstatin A and active Candida proteinase adhered in the same range as with denaturated proteinases in control tests. Our results suggest a function of Candida proteinases in the adherence process of blastoconidia to epithelia.
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Affiliation(s)
- M Borg-von Zepelin
- Abteilung Medizinische Mikrobiologie, Hygiene-Institut der Universität Göttingen, BR Deutschland
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Affiliation(s)
- M Ellis
- HCI International Medical Centre, Clydebank, U.K
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Fukazawa Y, Kagaya K. Molecular bases of adhesion of Candida albicans. JOURNAL OF MEDICAL AND VETERINARY MYCOLOGY : BI-MONTHLY PUBLICATION OF THE INTERNATIONAL SOCIETY FOR HUMAN AND ANIMAL MYCOLOGY 1997; 35:87-99. [PMID: 9147268 DOI: 10.1080/02681219780000971] [Citation(s) in RCA: 78] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The purpose of this review is to focus on the location and the adhesion activity of the protein (peptide) and the mannan moieties of the mannoprotein in the outer surface of the Candida albicans cell wall. A macromolecule of the mannoprotein located on the outermost surface is undoubtedly a strong adhesin comprising several adhesion molecules including protein and mannan. Mannoproteins can be divided into two classes, higher molecular weight peptidomannans (260 kDa) and lower molecular weight mannoproteins (50-66 kDa), both of which consist of similar mannans and disparate proteins or peptides which have distinct adhesion specificities. The protein moiety of mannoprotein can be divided functionally into two groups, lectin-like proteins and proteins recognizing arginine-glycine-aspartic acid (RGD) ligands. The latter proteins are further subdivided into two groups, CR2/CR3-like proteins and proteins binding extracellular matrix (ECM) proteins. Hydrophobicity of the cell surface of C. albicans influences adhesion of the organisms to epithelial cells. Degree of glycosylation of cell surface mannoproteins that affect yeast cell surface hydrophobicity affects adhesion of C. albicans to epithelial cells. The hydrophobic proteins may have low levels of glycosylation, and changes in glycosylation may determine exposure of hydrophobic protein regions at the cell surface. The serotype A-specific oligosaccharide of antigen 6 (pentaose or hexaose of mannan moiety) has been shown to exhibit marked adhesion ability for epithelial cells, and mannotetraose related to antigenic factor 5 which is present in both serotypes A and B showed adhesive activity for tissue macrophages. Proteinoceous adhesins of C. albicans are expressed preferably on the mycelial form. It is suggested that several of the adhesion molecules of C. albicans described above appear to complementarily utilize multiple adhesion mechanisms.
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Affiliation(s)
- Y Fukazawa
- Department of Microbiology, Yamanashi Medical University, Japan
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