title: Production and properties of keratinolytic proteases from three novel Gram-negative feather-degrading bacteria isolated from Brazilian soils.
abstract: The keratinolytic potential and protease properties of three novel Gram-negative feather-degrading bacteria isolated from Brazilian soils was described. Aeromonas hydrophila K12, Chryseobacterium indologenes A22 and Serratia marcescens P3 were able to degrade feather meal, producing high amounts of soluble proteins and forming thiol groups. The proteases of strains K12, A22 and P3 had optimal pH of 8.0, 7.5 and 6.0, respectively; this last is an uncommon feature for bacterial keratinases. The optimal temperature was in the range 45-55°C. All three proteases were active towards azokeratin and were inhibited by EDTA, suggesting that they are keratinolytic metalloproteases. The proteolytic activity of K12 was stimulated by organic solvents and the detergent SDS, suggesting its potential application for detergent formulations and peptide synthesis. Strains A22, K12 and P3 have great potential for use in biotechnological processes involving hydrolysis of keratinous byproducts.
authors.affiliation: Laboratório de Bioquímica e Microbiologia Aplicada, Departamento de Ciência e Tecnologia de Alimentos, ICTA, Universidade Federal do Rio Grande do Sul, Porto Alegre, 91501-970, Brazil.
authors.forename: Evelise
authors.initials: E
authors.lastname: Bach
authors.forename: Daniel Joner
authors.initials: DJ
authors.lastname: Daroit
authors.forename: Ana Paula Folmer
authors.initials: AP
authors.lastname: Corrêa
authors.forename: Adriano
authors.initials: A
authors.lastname: Brandelli
mesh_terms: D016980:Aeromonas hydrophila / Q000201:enzymology*; D000818:Animals; D001426:Bacterial Proteins / Q000378:metabolism*; D001673:Biodegradation, Environmental; D001938:Brazil; D045247:Chryseobacterium / Q000201:enzymology*; D003470:Culture Media; D004492:Edetic Acid / Q000494:pharmacology; D005241:Feathers / Q000737:chemistry / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis / Q000187:drug effects; D007218:Industrial Microbiology / Q000379:methods*; D007633:Keratins / Q000378:metabolism*; D010447:Peptide Hydrolases / Q000378:metabolism*; D011200:Poultry; D012706:Serratia marcescens / Q000201:enzymology*; D012967:Sodium Dodecyl Sulfate / Q000494:pharmacology; D012987:Soil; D012988:Soil Microbiology; D013379:Substrate Specificity; D013696:Temperature; D014866:Waste Products
chemical_list: D001426:Bacterial Proteins; D003470:Culture Media; D012987:Soil; D014866:Waste Products; D012967:Sodium Dodecyl Sulfate; D007633:Keratins; D004492:Edetic Acid; D010447:Peptide Hydrolases; C035855:keratinase