title: Genome and secretome analyses provide insights into keratin decomposition by novel proteases from the non-pathogenic fungus Onygena corvina.
abstract: Poultry processing plants and slaughterhouses produce huge quantities of feathers and hair/bristle waste annually. These keratinaceous wastes are highly resistant to degradation. Onygena corvina, a non-pathogenic fungus, grows specifically on feathers, hooves, horn, and hair in nature. Hence, the proteases secreted by O. corvina are interesting in view of their potential relevance for industrial decomposition of keratinaceous wastes. We sequenced and assembled the genome of O. corvina and used a method called peptide pattern recognition to identify 73 different proteases. Comparative genome analysis of proteases in keratin-degrading and non-keratin-degrading fungi indicated that 18 putative secreted proteases from four protease families (M36, M35, M43, and S8) may be responsible for keratin decomposition. Twelve of the 18 predicted protease genes could be amplified from O. corvina grown on keratinaceous materials and were transformed into Pichia pastoris. One of the recombinant proteases belonging to the S8 family showed high keratin-degrading activity. Furthermore, 29 different proteases were identified by mass spectrometry in the culture broth of O. corvina grown on feathers and bristle. The culture broth was fractionated by ion exchange chromatography to isolate active fractions with five novel proteases belonging to three protease families (S8, M28, and M3). Enzyme blends composed of three of these five proteases, one from each family, showed high degree of degradation of keratin in vitro. A blend of novel proteases, such as those we discovered, could possibly find a use for degrading keratinaceous wastes and provide proteins, peptides, and amino acids as valuable ingredients for animal feed.
authors.affiliation: Department of Chemistry and Bioscience, Aalborg University Copenhagen, 2450, Copenhagen, SV, Denmark.|Department of Chemical and Biochemical Engineering, Technical University of Denmark, Building 229, 2800, Kgs. Lyngby, Denmark.
authors.forename: Yuhong
authors.initials: Y
authors.lastname: Huang
authors.affiliation: Department of Chemistry and Bioscience, Aalborg University Copenhagen, 2450, Copenhagen, SV, Denmark.|Department of Chemical and Biochemical Engineering, Technical University of Denmark, Building 229, 2800, Kgs. Lyngby, Denmark.
authors.forename: Peter Kamp
authors.initials: PK
authors.lastname: Busk
authors.affiliation: Center for Microbial Communities, Department of Chemistry and Bioscience, Aalborg University, Fredrik Bajers Vej 7H, 9220, Aalborg East, Denmark.
authors.forename: Florian-Alexander
authors.initials: FA
authors.lastname: Herbst
authors.affiliation: Department of Chemistry and Bioscience, Aalborg University Copenhagen, 2450, Copenhagen, SV, Denmark. lenl@kt.dtu.dk.|Department of Chemical and Biochemical Engineering, Technical University of Denmark, Building 229, 2800, Kgs. Lyngby, Denmark. lenl@kt.dtu.dk.
authors.forename: Lene
authors.initials: L
authors.lastname: Lange
mesh_terms: D002852:Chromatography, Ion Exchange; D016681:Genome, Fungal; D007218:Industrial Microbiology; D007633:Keratins / Q000378:metabolism*; D020036:Onygenales / Q000201:enzymology* / Q000235:genetics / Q000378:metabolism*; D010447:Peptide Hydrolases / Q000235:genetics / Q000378:metabolism*; D010843:Pichia / Q000235:genetics / Q000378:metabolism; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D017422:Sequence Analysis, DNA
chemical_list: D011994:Recombinant Proteins; D007633:Keratins; D010447:Peptide Hydrolases
keywords: Enzyme blends; Genome; Keratinolytic protease; Onygena corvina; Peptide pattern recognition; Secretome