4株家蚕丝胶蛋白降解细菌的分类鉴定与培养温度研究

从缫丝厂废水池分离获得4株对家蚕丝胶蛋白具有较强降解活性的细菌。通过菌落的形态特征和生理生化特征分析及16S rDNA序列测定与同源性分析,对4株细菌进行分类鉴定的结果是:S45、Y3菌株为蜡状芽孢杆菌(Bacillus cereus),S68、X10菌株为短小芽孢杆菌(Bacillus pumilus)。温度对丝胶蛋白降解细菌的降解活性有影响,在培养温度为30℃时,S45、Y3、S68、X10菌株对家蚕丝胶蛋白的降解活性最高,其降解率分别为26.52%、20.27%、21.55%和28.86%。由于芽孢杆菌具有很强的耐热等抗逆能力,所以4株丝胶蛋白降解细菌有望应用于缫丝厂排放废水的处理。

Classification and Culture Temperature of 4 Bacterial Strains that Degrade Silkworm Sericin

4 strains that had high sericin degradation activities were obtained from the waste water of the reeling mill.We found that strains S45 and Y3 belonged to Bacillus cereus,and strains S68 and X10 belonged to Bacillus pumilus based on their morphological properties,physiological and biochemical characteristics,and phylogenetic analysis of their 16S rDNA sequences.We also found that culture temperature could influence their biodegradation activities to silkworm sericin.The degradation activities of all 4 strains (S45,Y3,S68 and X10) were the highest at 30 ℃,being 26.52%, 20.27%,21.55% and 28.86%,respectively.Since Bacillus strains are highly resistant to heat and other environmental stresses,these 4 strains that have high sericin degradation activities may be used to treat wastewater from reeling mills.