Characterization of an extracellular keratinase from Microsporum canis.
Extracellular keratinase (Ekase) 48-, 34- and 31.5-kDa polypeptides, which were isolated from Microsporum canis and examined by immunoblotting reacted with a monoclonal antibody against Ekase of M. canis. We analyzed the amino acid and determined the first 17 amino acid NH2-terminal sequences of the 48-, 34- and 31.5-kDa polypeptides. These polypeptides had a high aspartic acid, glycine and alanine content, respectively. The first 17 amino acid residues of the 34-kDa polypeptide were homologous to those of thermomycolin. This indicated that the 34-kDa polypeptide of Ekase is homologous to the thermomycolin produced by Malbranchea pulchella. Furthermore, Ekase was very heat-stable in the presence of 50 mM CaCl2 at 55 degrees C, since 50% of the initial activity remained. In contrast, no activity was detected after heating in the absence of CaCl2. These results indicate a close relationship between dermatophytes and M. pulchella.
Hamaguchi
T
T
Department of Dermatology, Showa University, Fujigaoka Hospital.
Morishita
N
N
Usui
R
R
Takiuchi
I
I
D000595:Amino Acid Sequence; D005656:Fungal Proteins; D008864:Microsporum / Q000201:enzymology*; D010447:Peptide Hydrolases / Q000737:chemistry / Q000302:isolation & purification*; D010455:Peptides / Q000737:chemistry / Q000302:isolation & purification*; D012697:Serine Endopeptidases / Q000737:chemistry
D005656:Fungal Proteins; D010455:Peptides; D010447:Peptide Hydrolases; C035855:keratinase; D012697:Serine Endopeptidases; C022729:Thermomycolin protein, Malbranchea sulfurea