Syed Dastager G, Lee Jae Chan, Li Wen-Jun, Kim Chang-Jin, Agasar Dayanand
National Institute of Interdisciplinary Science and Technology CSIR, Thiruvananthapuram, India.
Bioresour Technol. 2009 Mar;100(5):1868-71. doi: 10.1016/j.biortech.2008.09.047. Epub 2008 Nov 5.
A Streptomyces gulbargensis newly isolated, thermotolerant feather-degrading bacterial strain was investigated for its ability to produce keratinase enzyme. Maximum keratinolytic activity was observed at 45 degrees C and pH 9.0 at 120 h of incubation. Activity was completely stable (100%) between 30 and 45 degrees C and pH 7.0-9.0, respectively. Addition of starch to the growth medium affects the activity by means of increase in keratinase secretion. After seven days of cultivation, 10-fold increase (14.3 U ml(-1)) in keratinase activity was observed in the presence of 3g starch (per liter) of the medium. The enzyme was monomeric and had a molecular mass of 46 kDa. The enzyme activity was significantly inhibited by CaCl(2) and partly inhibited by EDTA, whereas, Na(2)SO(3) enhance the enzyme activity by 2.9 times more. In addition, native chicken feather was completely degraded at 96 h of incubation. The results obtained showed that newly isolated strain S. gulbargensis could be a useful in biotechnology in terms of valorization of keratin-containing wastes or in the leather industry.
对新分离出的耐热性羽毛降解细菌菌株古尔巴格链霉菌（Streptomyces gulbargensis）产生角蛋白酶的能力进行了研究。在培养120小时时，在45℃和pH 9.0条件下观察到最大角蛋白分解活性。活性在30至45℃和pH 7.0 - 9.0之间分别完全稳定（100%）。向生长培养基中添加淀粉通过增加角蛋白酶分泌来影响活性。培养七天后，在培养基中存在3g淀粉（每升）的情况下，观察到角蛋白酶活性增加了10倍（14.3 U ml(-1)）。该酶为单体，分子量为46 kDa。CaCl(2)显著抑制该酶活性，EDTA部分抑制该酶活性，而Na(2)SO(3)使酶活性提高2.9倍。此外，天然鸡毛在培养96小时时完全降解。所得结果表明，新分离的菌株古尔巴格链霉菌在含角蛋白废物的增值或皮革工业方面在生物技术中可能是有用的。
