Study of novel alkalikeratinase enzyme

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We isolated a feather-degrading alkalophilic Bacillus sp. FA30-01 from the compost of a poultry farm. The isolate degraded completely the pieces of feather in liquid culture (pH 10.5) under the culture condition 30℃ for 3 days. FA30-01 strain was Gram-positive, spore-forming and rod-shaped bacterium and was identified with Bacillus pseudofirmus. by the analysis of 16SrDNAKeratinase enzyme produced by FA30-01 was refined by using the ammonium sulfate precipitation, the negative ion of DEAB Toyopearl exchange chromatography, and the hydroxyapatite chromatography. The refinement level was 14.5 times. The molecular weight of this enzyme was 27.5kDa and an isoelectric point of 5.9.The enzyme had the activity at pH 5.1-11.5 and 30-80℃ for azokeratin. The optimum pH and temperature for keratinase activity were pH 8.8-10.3 and 60℃. And this enzyme belonged to the serine-type protease.Subtilisin ALP I and this enzyme had 90% of homology in N-terminal amino acid sequence. Since this enzyme differed from ALP I in a molecular weight, heat resistance or isoelectric point, these two enzymes were suggested to be different enzyme.