title: Partial purification and characterization of a 37 kDa extracellular proteinase from Trichophyton vanbreuseghemii.
abstract: An exocellular proteinase synthesized by the geophilic dermatophyte Trichophyton vanbreuseghemii has been purified and characterized. The fungus obtained from soil in Iran was cultivated in modified Czapek-Dox liquid medium containing 0.1% bacteriological peptone and 1% glucose as the nitrogen and carbon sources. Partial purification of the proteinase was accomplished by (NH(4))(2)SO(4) precipitation, followed by ion exchange chromatography. Analysis of the enzyme by SDS-PAGE revealed a single polypeptide chain with an apparent molecular mass of 37 kDa. Proteinase activity was optimum at pH 8, but remained high in the range of pH 7-11. Moreover, the partially purified enzyme presented a keratinolytic activity as evidenced by the keratin azure test. The inhibition profile and the good activity of the enzyme towards the synthetic substrate N-succinyl-Ala-Ala-Pro-Phe-p-nitroanilide suggested that it belonged to the chymotrypsin/subtilisin group of serine proteinases. The keratinolytic properties of T. vanbreuseghemii suggest that this fungus may be an alternative for the recycling of industrial keratinic wastes.
authors.affiliation: Department of Medical Mycology and Parasitology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Hossein
authors.initials: H
authors.lastname: Moallaei
authors.forename: Farideh
authors.initials: F
authors.lastname: Zaini
authors.forename: Gérald
authors.initials: G
authors.lastname: Larcher
authors.forename: Bertrand
authors.initials: B
authors.lastname: Beucher
authors.forename: Jean-Philippe
authors.initials: JP
authors.lastname: Bouchara
mesh_terms: D011232:Chemical Precipitation; D002852:Chromatography, Ion Exchange; D006863:Hydrogen-Ion Concentration; D007558:Italy; D007633:Keratins / Q000378:metabolism; D008970:Molecular Weight; D012697:Serine Endopeptidases / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D012988:Soil Microbiology; D014249:Trichophyton / Q000201:enzymology*
chemical_list: D007633:Keratins; D012697:Serine Endopeptidases