Taxonomic group: fungi / Ascomycota, Ascomycota, Ascomycota, Mucoromycota, Ascomycota, Ascomycota, Ascomycota
(Phylum: Ascomycota, Ascomycota, Ascomycota, Mucoromycota, Ascomycota, Ascomycota, Ascomycota)
Organ / tissue: cell wall
The structure was elucidated in this paperNCBI PubMed ID: 29720523Publication DOI: 10.1128/mSphere.00094-18Journal NLM ID: 101674533Publisher: Washington, DC: American Society for Microbiology
Correspondence: burnham-marusich
med.unr.edu
Institutions: Department of Microbiology and Immunology, University of Nevada, Reno School of Medicine, Reno, USA, Mayo Clinic, Rochester, USA
Ascomycetes and zygomycetes account for the majority of (i) fungi responsible for cutaneous, subcutaneous, and invasive human fungal infections, (ii) plant fungal pathogens, (iii) fungi that threaten global biodiversity, (iv) fungal agents of agricultural spoilage, and (v) fungi in water-damaged buildings. Rapid recognition of fungal infection (or contamination) enables early treatment (or remediation). A bioinformatics search found homologues of Saccharomyces cerevisiae Mnn9p present in members of the Zygomycota and Ascomycota phyla and absent in members of the Chytridiomycota and Basidiomycota. Mnn9p is a component of the yeast mannan polymerization complex and is necessary for α-1,6 mannan production. A monoclonal antibody (2DA6) was produced that was reactive with purified mannans of Mucor, Rhizopus, Aspergillus, Fusarium, and Candida species. Experimentation using a 2DA6 antigen capture enzyme-linked immunosorbent assay (ELISA) and extracts of fungi from the four phyla found agreement between the presence or absence of Mnn9p homologues and production or lack of production of mannan reactive with 2DA6. Studies of cell extracts from yeast mannan mutants identified α-1,6 mannan as the epitope recognized by 2DA6. To translate this finding into a point-of-use diagnostic, a 2DA6 lateral flow immunoassay was constructed that detected mannan in (i) extracts of dermatophytes and fungi that produce trauma-related infection and (ii) tissue from plants infected with Grosmannia clavigera or Sclerotium cepivorum These studies (i) revealed that the conservation of α-1,6-linked mannan in fungi of the Zygomycota and Ascomycota can be exploited as a broad diagnostic target and (ii) have provided a means to detect that target in an immunoassay platform that is well suited for clinic or field use.IMPORTANCE A key question asked when faced with an infection, an infestation, or environmental damage is whether it is a fungus. Identification of fungi as the cause of the problem can lead to remediation or treatment. Zygomycetes and ascomycetes account for the vast majority of fungal causes of human, animal, and plant disease, large-scale biodiversity loss, agricultural spoilage, and contamination of water-damaged buildings. These studies revealed the conservation of a common cell wall structural component of zygomycetes and ascomycetes to be a diagnostic target applicable to multiple pathogenic fungi and have leveraged that insight for practical use. Monoclonal antibodies reactive with this pan-fungal structure were produced and used to construct immunoassays (including ELISA and lateral flow assay) for detection of a broad range of pathogenic fungi.
mannan, Diagnostics, Mnn9, immunodetection, invasive fungal infection, lateral flow immunoassay, point of care
Structure type: structural motif or average structure
Location inside paper: p. 2, paragraph 4
Compound class: N-glycan, mannan
Contained glycoepitopes: IEDB_130701,IEDB_136104,IEDB_140116,IEDB_141111,IEDB_141793,IEDB_141795,IEDB_141828,IEDB_141829,IEDB_141830,IEDB_141831,IEDB_141832,IEDB_141833,IEDB_141834,IEDB_143632,IEDB_144983,IEDB_152206,IEDB_153220,IEDB_153756,IEDB_153762,IEDB_153763,IEDB_164174,IEDB_164175,IEDB_164176,IEDB_164480,IEDB_174840,IEDB_76933,IEDB_857732,IEDB_857735,IEDB_983930,SB_136,SB_191,SB_196,SB_197,SB_198,SB_44,SB_67,SB_72
Methods: GC-MS, ELISA, methanolysis, enzymatic digestion, affinity chromatography, periodate oxidation, phenol-sulfuric acid assay, centrifugation, filtration, flow filtration, LFIA
Biological activity: binds to Mab 2DA6; Reactivity of mannan rises with the decrease of the branching degree
Enzymes that release or process the structure: proteinase K, Mnn9p, Mnn2p
Biosynthesis and genetic data: biochemical data
Comments, role: mannan chain is connected to N-glycan core
NCBI Taxonomy refs (TaxIDs): 746128,
5476,
169388,
36080,
1266529Reference(s) to other database(s): GTC:G92497NG
Show glycosyltransferases
There is only one chemically distinct structure:
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