title: A hemolytic peptide from the mycophilic fungus Sepedonium chrysospermum (Bull.) Fr.
abstract: The hemolytic activity of an extract of the mycoparasite Sepedonium chrysospermum (teleomorph Hypomyces chrysospermus) was detected and characterized. Extraction of the fungal biomass by methanol yielded a fraction in which the hemolytic activity against human red blood cells corresponded to a peptide with a molecular mass of 7,653.72 Da and an isoelectric point of approximately 5.8. The peptide was temperature resistant, and the hemolysis was only partially inhibited, even after a 30-min pre-incubation at 100°C. Its hemolytic activity was unaffected by treatment with proteolytic enzymes such as trypsin. Among the divalent cations assayed, Hg(2+) was the strongest inhibitor of hemolysis. The reducing agent, dithiothreitol, and the membrane lipid, cholesterol, demonstrated concentration-dependent inhibitory activities. Finally, hemolytic activity triggered by the peptide was analyzed by scanning electron microscopy, and a pore-forming activity was detected.
authors.affiliation: Mycology Laboratory, Department for the Study of Territory and its Resources (DIP.TE.RIS), Polo Botanico Hanbury, University of Genoa, Corso Dogali 1M Genoa, Genoa, Italy. elisa.sanguineti@unige.it
authors.forename: Elisa
authors.initials: E
authors.lastname: Sanguineti
authors.forename: Maria E
authors.initials: ME
authors.lastname: Cosulich
authors.forename: Annalisa
authors.initials: A
authors.lastname: Salis
authors.forename: Gianluca
authors.initials: G
authors.lastname: Damonte
authors.forename: Mauro G
authors.initials: MG
authors.lastname: Mariotti
authors.forename: Mirca
authors.initials: M
authors.lastname: Zotti
mesh_terms: D002784:Cholesterol / Q000378:metabolism; D004229:Dithiothreitol / Q000378:metabolism; D004791:Enzyme Inhibitors / Q000378:metabolism; D004912:Erythrocytes / Q000187:drug effects / Q000648:ultrastructure; D006460:Hemolysin Proteins / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D006801:Humans; D006999:Hypocreales / Q000737:chemistry / Q000472:pathogenicity*; D007526:Isoelectric Point; D008628:Mercury / Q000378:metabolism; D008855:Microscopy, Electron, Scanning; D008970:Molecular Weight; D010455:Peptides / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D055550:Protein Stability; D013696:Temperature
chemical_list: D004791:Enzyme Inhibitors; D006460:Hemolysin Proteins; D010455:Peptides; D002784:Cholesterol; D008628:Mercury; D004229:Dithiothreitol