Degradation of raw feather by a novel high molecular weight extracellular protease from newly isolated Bacillus cereus DCUW

J Ind Microbiol Biotechnol. 2008 Aug;35(8):825-34. doi: 10.1007/s10295-008-0354-5. Epub 2008 Apr 22.

Abstract

Biotreatment of feather wastes and utilization of the degraded products in feed and foodstuffs has been a challenge. In the present study, we have demonstrated the degradation of feather waste by Bacillus cereus DCUW strain isolated during a functional screening based microbial diversity study on East Calcutta Wetland Area. A high molecular weight keratinolytic protease from feather degrading DCUW strain was purified and characterized. Moreover, utilization of degraded products during feather hydrolysis was developed and demonstrated. The purified keratinolytic protease was found to show pH and temperature optima of 8.5 and 50 degrees C, respectively. PMSF was found to inhibit the enzyme completely. The purified enzyme showed molecular weight of 80 kDa (from SDS-PAGE). The protease was found to have broad range substrate specificities that include keratin, casein, collagen, fibrin, BAPNA and gelatin. The protease was identified as minor extracellular protease (Vpr) by RT-PCR and northern blotting techniques. This is the first report describing the characterization of minor extracellular protease (Vpr) and its involvement in feather degradation in B. cereus group of organisms.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Bacillus cereus / enzymology*
  • Bacillus cereus / isolation & purification
  • Blotting, Northern
  • Electrophoresis, Polyacrylamide Gel
  • Environmental Microbiology
  • Enzyme Stability
  • Feathers / metabolism*
  • Hydrogen-Ion Concentration
  • India
  • Industrial Waste*
  • Keratins / metabolism
  • Molecular Weight
  • Peptide Hydrolases / chemistry
  • Peptide Hydrolases / isolation & purification*
  • Peptide Hydrolases / metabolism*
  • Protease Inhibitors / pharmacology
  • RNA, Bacterial / genetics
  • Reverse Transcriptase Polymerase Chain Reaction
  • Substrate Specificity
  • Temperature
  • Tosyl Compounds / pharmacology
  • Wetlands

Substances

  • Industrial Waste
  • Protease Inhibitors
  • RNA, Bacterial
  • Tosyl Compounds
  • 4-toluenesulfonyl fluoride
  • Keratins
  • Peptide Hydrolases