title: Purification and characterization of a mycelial catalase from Scedosporium boydii, a useful tool for specific antibody detection in patients with cystic fibrosis.
abstract: Scedosporium boydii is an opportunistic filamentous fungus which may be responsible for a wide variety of infections in immunocompetent and immunocompromised individuals. This fungus belongs to the Scedosporium apiospermum species complex, which usually ranks second among the filamentous fungi colonizing the airways of patients with cystic fibrosis (CF) and may lead to allergic bronchopulmonary mycoses, sensitization, or respiratory infections. Upon microbial infection, host phagocytic cells release reactive oxygen species (ROS), such as hydrogen peroxide, as part of the antimicrobial response. Catalases are known to protect pathogens against ROS by detoxification of the hydrogen peroxide. Here, we investigated the catalase equipment of Scedosporium boydii, one of the major pathogenic species in the S. apiospermum species complex. Three catalases were identified, and the mycelial catalase A1 was purified to homogeneity by a three-step chromatographic process. This enzyme is a monofunctional tetrameric protein of 460 kDa, consisting of four 82-kDa glycosylated subunits. The potential usefulness of this enzyme in serodiagnosis of S. apiospermum infections was then investigated by an enzyme-linked immunosorbent assay (ELISA), using 64 serum samples from CF patients. Whatever the species involved in the S. apiospermum complex, sera from infected patients were clearly differentiated from sera from patients with an Aspergillus fumigatus infection or those from CF patients without clinical and biological signs of a fungal infection and without any fungus recovered from sputum samples. These results suggest that catalase A1 is a good candidate for the development of an immunoassay for serodiagnosis of infections caused by the S. apiospermum complex in patients with CF.
authors.affiliation: L'UNAM Université, Université d'Angers, Groupe d'Etude des Interactions Hôte-Pathogène, EA 3142, Institut de Biologie en Santé-IRIS, Angers, France.
authors.forename: Sara
authors.initials: S
authors.lastname: Mina
authors.affiliation: L'UNAM Université, Université d'Angers, Groupe d'Etude des Interactions Hôte-Pathogène, EA 3142, Institut de Biologie en Santé-IRIS, Angers, France agnes.marot@univ-angers.fr maxime.fleury@univ-angers.fr.
authors.forename: Agnès
authors.initials: A
authors.lastname: Marot-Leblond
authors.affiliation: L'UNAM Université, Université d'Angers, Groupe d'Etude des Interactions Hôte-Pathogène, EA 3142, Institut de Biologie en Santé-IRIS, Angers, France L'UNAM Université, Centre Hospitalier Universitaire d'Angers, Laboratoire de Parasitologie-Mycologie, Institut de Biologie en Santé-PBH, CHU, Angers, France.
authors.forename: Bernard
authors.initials: B
authors.lastname: Cimon
authors.affiliation: L'UNAM Université, Université d'Angers, Groupe d'Etude des Interactions Hôte-Pathogène, EA 3142, Institut de Biologie en Santé-IRIS, Angers, France agnes.marot@univ-angers.fr maxime.fleury@univ-angers.fr.
authors.forename: Maxime J J
authors.initials: MJ
authors.lastname: Fleury
authors.affiliation: L'UNAM Université, Université d'Angers, Groupe d'Etude des Interactions Hôte-Pathogène, EA 3142, Institut de Biologie en Santé-IRIS, Angers, France.
authors.forename: Gérald
authors.initials: G
authors.lastname: Larcher
authors.affiliation: L'UNAM Université, Université d'Angers, Groupe d'Etude des Interactions Hôte-Pathogène, EA 3142, Institut de Biologie en Santé-IRIS, Angers, France L'UNAM Université, Centre Hospitalier Universitaire d'Angers, Laboratoire de Parasitologie-Mycologie, Institut de Biologie en Santé-PBH, CHU, Angers, France.
authors.forename: Jean-Philippe
authors.initials: JP
authors.lastname: Bouchara
authors.affiliation: L'UNAM Université, Université d'Angers, Groupe d'Etude des Interactions Hôte-Pathogène, EA 3142, Institut de Biologie en Santé-IRIS, Angers, France.
authors.forename: Raymond
authors.initials: R
authors.lastname: Robert
mesh_terms: D000908:Antibodies, Fungal / Q000097:blood*; D000946:Antigens, Fungal / Q000737:chemistry / Q000302:isolation & purification; D002374:Catalase / Q000737:chemistry / Q000302:isolation & purification; D002853:Chromatography, Liquid / Q000379:methods; D003550:Cystic Fibrosis / Q000150:complications*; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D006801:Humans; D008970:Molecular Weight; D025282:Mycelium / Q000201:enzymology; D009181:Mycoses / Q000175:diagnosis*; D055503:Protein Multimerization; D021681:Scedosporium / Q000201:enzymology*; D012698:Serologic Tests / Q000379:methods
chemical_list: D000908:Antibodies, Fungal; D000946:Antigens, Fungal; D002374:Catalase