一株羽毛降解菌的分离与鉴定

【目的】从土壤中分离并鉴定羽毛降解菌,测定其生长最适温度及起始pH,并观察酶活动态。【方法】采用系列稀释法和选择培养基法筛选目的菌株,基于16S rRNA基因序列及Biolog方法鉴定其分类地位,利用全自动生长曲线分析仪监测菌株的最适生长条件,并通过测定蛋白水解活性观察其酶活动态。【结果】从混合羽毛的土壤样品中筛选到一株羽毛降解菌,命名为菌株GIMN1.015,初步判定该菌株属于芽孢八叠球菌属(Sporosarcina)。最适生长pH为9.0,温度为30°C。蛋白水解活性最高值出现在培养后96 h。【结论】菌株GIMN1.015在利用羽毛角蛋白资源中具有潜在的应用价值。这是芽孢八叠球菌在羽毛降解方面的首次报道。

Isolation and characterization of a feather-degrading bacterium

Objective] This study is aimed to isolate and characterize feather-degrading bacteria from soil, and to determine the optimal temperature and initial pH for growth and further to observe the dynamic of enzyme activity. Methods] Serial dilution on agar plate and selective medium culture techniques were used for screening bacteria. Strain identification was based on phylogenetic analysis of 16S rRNA gene sequence and Biolog analysis. Optimal growth con-ditions were measured by automated microbiology growth curve analyzer. The proteolytic ac-tivity assay was carried out to observe the dynamic of enzyme activity. Results] A feather-degrading bacterial strain, designated as GIMN1.015, was isolated and screened from the soil mixed with feathers. The strain was preliminarily identified as a strain of the genus Sporosarcina. The optimal pH and temperature for growth were 9.0 and 30 °C, respectively. The peak value of proteolytic activity appeared at 96 h of incubation time. Conclusion] Strain GIMN1.015 has the potential for the application of feather keratin sources. This is the first report on the feather degrading by Sporosarcina.