Enhancing Plant Growth by Chicken Feather Compost Obtained from Feather Degradation by Streptomyces enissocaesilis

Nowadays, feathers are a major by-product of the poultry industry. Due to the increasing production of feathers from poultry industries, the untreated feathers could become pollutants. Feathers account for 5-7% of the total weight which is constituted of 90% keratin. Bioconversion is widely accepted as a low-cost and environmentally gentle process but limited by the availability of safe and highly efficient feather degrading bacteria. In this study, 15 actinomycete isolates were isolated, purified and screened for keratinase production using solid and broth media. Out of the 15 isolates, 9 recorded keratinase activities. The isolate AM1 was the most active one, thus it was selected for further studied. Using morphological, physiological and biochemical characters in addition to 16S rRNA, it was identified as Streptomyces enissocaesilis AM1 with 95% similarity level to S. enissocaesilis. This isolate can efficiently degrade feathers. Keratinase enzymes from Streptomyces enissocaesilis AM1 showed optimal activity at pH 7 and 50 degrees C. Mechanism of degradation includes, sulfitolysis, proteolysis, followed by deamination. In conclusion, Streptomyces enissocaesilis AM1 can grow on keratin as a carbon sourceand secret keratinase which degrade keratin to small peptide chains, amino acids, and minerals which can be used as organic fertilizer for enhancing plant growth.