Previous Article | Next Article ![]()
Appl. Environ. Microbiol., Oct 1995, 3705-3710, Vol 61, No. 10
B Bockle, B Galunsky and R Muller
A serine protease from the keratin-degrading Streptomyces pactum DSM 40530
was purified by casein agarose affinity chromatography. The enzyme had a
molecular weight of 30,000 and an isoelectric point of 8.5. The proteinase
was optimally active in the pH range from 7 to 10 and at temperatures from
40 to 75 degrees C. The enzyme was specific for arginine and lysine at the
P1 site and for phenylalanine and arginine at the P1' site. It showed a
high stereoselectivity and secondary specificity with different synthetic
substrates. The keratinolytic activity of the purified proteinase was
examined by incubation with the insoluble substrates keratin azure, feather
meal, and native and autoclaved chicken feather downs. The S. pactum
proteinase was significantly more active than the various commercially
available proteinases. After incubation with the purified proteinase, a
rapid disintegration of whole feathers was observed. But even after several
days of incubation with repeated addition of enzymes, less than 10% of the
native keratin substrate was solubilized. In the presence of
dithiothreitol, degradation was more than 70%.
Copyright © 1995, American Society for Microbiology
Characterization of a keratinolytic serine proteinase from Streptomyces pactum DSM 40530
Department of Biotechnology II, Technical University of Hamburg- Harburg, Germany.
This article has been cited by other articles:
| J. Bacteriol. | Microbiol. Mol. Biol. Rev. | Eukaryot. Cell | All ASM Journals |
|---|