Molecular identification and optimization of keratinase production in keratin-degrading bacteria isolated from soil poultry of Marvdasht city
Subject Areas : Environmental MicrobiologySomayeh Khodayari 1 , Farshid Kafilzadeh 2
1 - M.Sc., Young Researchers and Elite Club, Jahrom branch, Islamic Azad University, Jahrom, Iran.
2 - Professor, Department of Microbiology, Jahrom branch, Islamic Azad University, Jahrom, Iran.
Keywords: Bacillus cereus, Keratinase enzyme, Feather-degrading bacteria,
Abstract :
Background & Objectives: Feather is one of the environmental pollutants that about 90% of its weight is made of highly resistant creatine plates. A number of bacteria are able to produce a keratinase enzyme in the presence of keratin substrate. The purpose of this study was isolation and molecular identification of keratin- degrading bacteria from the soil of poultry farms around Marvdasht city in order to measure keratinase activity in superior creatine-degrading strains. Material & Methods: In this study, 15 soil samples from poultry farms around Marvdasht city was collected. Seven bacterial isolates were cultured on a feather meal medium. Five isolates that showed clear degradation zone, were chosen for further chemical and molecular identification. The bacteria were sequenced, and a specific accession number in the gene bank was allocated to each of them as a new strain Then, all five isolates were assessed for the level of keratinase enzyme production. Result: All isolates belonged to Bacillus species. All five isolates were able to completely degrade keratine. The most keratinase activity was reported 17.12 (ml/min) for Bacillus cereus SKH1. Conclusion: Different species of Bacillus in this study showed the ability to produce a keratinase enzyme in the presence of keratin substrate. Investigating the level of keratinase activity in bacterial isolates showed that all have the potential treat feather waste.
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