Extremophiles

, Volume 10, Issue 3, pp 229–235

Isolation and characterization of a feather-degrading enzyme from Bacillus pseudofirmus FA30-01

  • Mio Kojima
  • Mieko Kanai
  • Mari Tominaga
  • Shunichi Kitazume
  • Akira Inoue
  • Koki Horikoshi
Original Paper

DOI: 10.1007/s00792-005-0491-y

Cite this article as:
Kojima, M., Kanai, M., Tominaga, M. et al. Extremophiles (2006) 10: 229. doi:10.1007/s00792-005-0491-y

Abstract

We isolated the feather-degrading Bacillus pseudofirmus FA30-01 from the soil sample of poultry farm. The isolate completely degraded feather pieces after liquid culture at 30°C (pH 10.5) for 3 days. Strain FA30-01 is a Gram-positive, spore-forming, rod-shaped bacterium and was identified with B. pseudofirmus based on 16S rDNA analysis. The keratinase enzyme produced by strain FA30-01 was refined using ammonium sulfate precipitation, negative-ion DEAE Toyopearl exchange chromatography, and hydroxyapatite chromatography. The refinement level was 14.5-fold. The molecular weight of this enzyme was 27.5 kDa and it had an isoelectric point of 5.9. The enzyme exhibited activity at pH 5.1–11.5 and 30–80°C with azokeratin as a substrate, although the optimum pH and temperature for keratinase activity were pH 8.8–10.3 and 60°C, respectively. This enzyme is one of the serine-type proteases. Subtilisin ALP I and this enzyme had 90% homology in the N-terminal amino acid sequence. Since this enzyme differed from ALP I in molecular weight, heat resistance and isoelectric point, they are suggested to be different enzymes.

Keywords

Extremophiles Alkaliphile Keratinase Feather-degrading enzyme Bacillus 

Copyright information

© Springer-Verlag 2006

Authors and Affiliations

  • Mio Kojima
    • 1
  • Mieko Kanai
    • 2
  • Mari Tominaga
    • 2
  • Shunichi Kitazume
    • 2
  • Akira Inoue
    • 1
    • 2
    • 3
  • Koki Horikoshi
    • 3
  1. 1.Graduate School of Life SciencesToyo UniversityGunma 374-0193Japan
  2. 2.Faculty of Life SciencesToyo UniversityGunma 374-0193Japan
  3. 3.Extremobiosphere Research CenterJapan Agency for Marine-Earth Science and Technology (JAMSTEC)Yokosuka 237-0061Japan