Yamamura Shohei, Morita Yasutaka, Hasan Quamrul, Rao Sathuluri Ramachandra, Murakami Yuji, Yokoyama Kenji, Tamiya Eiichi
School of Materials Science, Japan Advanced Institute of Science and Technology, 1-1 Asahidai, Tatsunokuchi, Ishikawa 923-1292, Japan.
J Biosci Bioeng. 2002;93(6):595-600.
A keratin-degrading bacterium was isolated from soil containing deer fur. An axenic culture of the keratin-degrading bacterium was obtained in liquid culture using a keratin enrichment technique. The isolated bacterium was gram negative and catalase- and oxidase-positive. Transmission electron microscopic observations showed that the bacterium was rod-shaped, 1.0-1.3 microm long and 0.7 microm in diameter. Phylogenetic analysis of 16S rDNA revealed that the new isolate has only 90.6% homology with Stenotrophomonas nitritireducens. Hence, this new bacterium was designated as Stenotrophomonas sp. D-1. The optimum temperature was determined to be 20 degrees C for maximum growth and keratinolytic enzyme production. Amino acid data, obtained after treating keratin powder with the supernatant culture, suggest that the major free amino acids resulting from keratin degradation are phenylalanine, tyrosine and valine. In addition, native chicken feather was degraded completely at 20 degrees C in 2.5 d by this bacterium.
从含有鹿毛的土壤中分离出一种角蛋白降解细菌。采用角蛋白富集技术在液体培养中获得了该角蛋白降解细菌的纯培养物。分离出的细菌革兰氏阴性，过氧化氢酶和氧化酶呈阳性。透射电子显微镜观察表明，该细菌呈杆状，长1.0 - 1.3微米，直径0.7微米。16S rDNA的系统发育分析表明，新分离菌株与亚硝酸盐还原寡养单胞菌的同源性仅为90.6%。因此，这种新细菌被命名为寡养单胞菌属D - 1。确定最佳温度为20℃，以实现最大生长和角蛋白水解酶的产生。用上清液培养物处理角蛋白粉后获得的氨基酸数据表明，角蛋白降解产生的主要游离氨基酸是苯丙氨酸、酪氨酸和缬氨酸。此外，该细菌在20℃下2.5天内可将天然鸡毛完全降解。
