Park Geun-Tae, Son Hong-Joo
Research and University-Industry Cooperation, Pusan National University, Busan 609-735, Republic of Korea.
Microbiol Res. 2009;164(4):478-85. doi: 10.1016/j.micres.2007.02.004. Epub 2007 Apr 24.
The aim of this study was to investigate environmental conditions affecting chicken feather degradation and keratinolytic enzyme production by Bacillus megaterium F7-1, a feather-degrading mesophilic bacterium. B. megaterium F7-1 degraded whole chicken feather completely within 7 days. The bacterium grew with an optimum at pH 7.0-11.0 and 25-40 degrees C, where maximum keratinolytic activity was also observed. The production of keratinolytic enzyme by B. megaterium F7-1 was inducible with feather. Keratinolytic enzyme production by B. megaterium F7-1 at 0.6% (w/v) skim milk was 468U/ml, which was about 9.4-fold higher than that without skim milk. The amount of keratinolytic enzyme production depended on feather concentrations. The degradation rate of autoclaved chicken feathers by cell-free culture supernatant was 26% after 24h of incubation, but the degradation of untreated chicken feathers was unsuccessful. B. megaterium F7-1 effectively degraded feather meal, duck feather and human nail, whereas human hair and sheep wool showed relatively low degradation rates. B. megaterium F7-1 presented high keratinolytic activity and was very effective in feather degradation, providing potential use for biotechnological processes of keratin hydrolysis.
本研究的目的是调查影响巨大芽孢杆菌F7-1（一种降解羽毛的嗜温细菌）降解鸡毛及产生角蛋白酶的环境条件。巨大芽孢杆菌F7-1在7天内可完全降解整根鸡毛。该细菌在pH 7.0 - 11.0和25 - 40摄氏度条件下生长最佳，在此条件下也观察到最大角蛋白酶活性。巨大芽孢杆菌F7-1产生角蛋白酶是由羽毛诱导的。在0.6%（w/v）脱脂乳中，巨大芽孢杆菌F7-1产生的角蛋白酶为468U/ml，比无脱脂乳时高出约9.4倍。角蛋白酶产生量取决于羽毛浓度。经高压灭菌的鸡毛在无细胞培养上清液中孵育24小时后的降解率为26%，但对未处理鸡毛的降解未成功。巨大芽孢杆菌F7-1能有效降解羽毛粉、鸭毛和人指甲，而人发和羊毛的降解率相对较低。巨大芽孢杆菌F7-1具有较高的角蛋白酶活性，在羽毛降解方面非常有效，为角蛋白水解的生物技术过程提供了潜在用途。
