摘要
从湖北工业大学巡司河附近的土壤和污水中采集到的3个样品,经富集培养,分离到14株能产生弹性蛋白酶的菌株,反复初筛、复筛后,分离到一株产胞外弹性蛋白酶较高且稳定的细菌,经初步鉴定属枯草芽孢杆菌(Bacil-lussubtilis)。该菌的生长温度为37℃,属革兰氏阳性菌,要求培养基的pH为7.0,对该菌进行化学诱变,诱变剂选用硫酸二乙酯(DES),诱变处理后绘制致死曲线。诱变浓度为1%,诱变时间为50min时,该菌的致死率达到77.5%。在此诱变剂量下,选透明圈直径与菌落直径之比最大的菌落进行酶活测定,在波长为495nm同一稀释倍数下,诱变前该菌酶活为74.25U/mL,诱变后的酶活为98.55U/mL,较出发菌株提高了33%。
Strains capable of secreting extracellular elastase were isolated from the soil and waster sample that near the xunsi river of Hubei University of Technology ,of them 14 strains produced elastase.Strain with the highest-yield elastase was identified as Bacillus subtilis.This strain growth temperature is 37 ℃, is the Gram-positive bacteria strain, request culture medium pH is 7.0, carries on chemistry mutagenesis to this strain, the mutagen se- lects diethyl sulfate （DES）, after mutafacient processing draws up the lethal curve. The mutafacient density is 1%, when the mutafacient time is 50 minutes, this strain lethality rate achieves 77.5 %. Under this mutagenesis dosage, chooses ratio of biggest of colony the transparent circle diameter and the colony diameter carries on the enzyme to live the determination, in the wave length is under the 495 nm identical dilution multiple, before the mutagenesis this strain enzyme activity is 74.25 U/mL, after the mutafacient enzyme activity is 98.55 U/mL, enhanced 33 %.
出处
《食品研究与开发》
CAS
北大核心
2006年第11期14-18,共5页
Food Research and Development
基金
湖北省教育厅重点项目(2004D009)
关键词
弹性蛋白酶
枯草芽孢杆菌
筛选
化学诱变
酶活测定
elastase
Bacillus subtilis
screening
chemistry mutagenesis
the determination of enzyme activity
