ANNALS OF MICROBIOLOGY, cilt.53, sa.1, ss.85-93, 2003 (SCI-Expanded)
A wild type Streptomyces strain BA(7) which was isolated from soil, showed a high keratinolytic activity when cultured on native feather medium. Optimum keratinolytic activity was observed at 50 degreesC and pH 8.5 when using fluid supernatant obtained from aerated culture of this organism. The keratinolytic activity was completely stable (100%) between 30 and 60 degreesC. The molecular weight of crude enzyme was estimated by SDS-PAGE about 44000 Da. The degradation of intact feathers by Streptomyces sp. BA(7) keratinase was obtained after 24 h of incubation at 50 degreesC. Keratinolytic activity was partially inhibited by 1, 10-phenanthroline, but slightly inhibited by CaCl2, ZnCl2, and SDS. In addition keratinolytic activity was enhanced by DMSO, EDTA, Triton-X 100 and sodium sulphite. Streptomyces strain BA(7) could be a useful in biotechnology in therms of valorization of keratin-containing wastes or in the leather industry.