羽毛降解菌株Streptomyces sp.DJ产生的蛋白酶酶学性质

Characteristics of Proteinases Produced by a feather-degrading Streptomyces sp.DJ Strian

从羽毛废弃物堆的土壤中采集样品,通过富集培养、初筛和复筛分离出一株高效降解羽毛的DJ菌株;对该菌株的形态学观察和基于16S rDNA序列的系统进化分析,初步鉴定为链霉菌Streptomyces sp.DJ。该菌株在32℃摇床培养10 d后,对天然羽毛的降解率高达50%,且羽毛水解产物中含有多种自由氨基酸。该菌株产生的蛋白酶最适反应温度为45℃,最适反应pH为10.0;对羽毛的降解能力高于商品化的碱性蛋白酶和木瓜蛋白酶,对疏水性或亲水性的自然底物也具有较强的水解能力。以上结果表明:DJ菌株及其产生的蛋白酶具有良好的应用潜力。

A DJ strain with a high efficience of feather degrading capability was isolated from the soil of feather waste by the enrichment culture and the screening process.The strain was identified as Streptomyces sp.according to morphologic observation,16S rDNA sequence alignment,and phylogenetic trees analysis.After fermenting at32℃for10days,the feather degradation rate reached50%,and the feather hydrolysate was found to contain amino acids.The protease produced by the DJ strain had a maximal activity at45℃,and the optimum reactive pH at100.The protease displayed a higher hydrolysis activity to feather than Alcalase and Papain,and had a strong hydrolysis ability to the hydrophobic or hydrophilic natural substrates.The results indicated that the DJ strain and its protease was of potential application prospects.