A Novel Screening Method for Isolating High Cholesterol Oxidase Producing Strain / 微生物学通报

ABSTRACT

The cholesterol oxidase producing strain Brevibacterium sp.DGCDC-82 was treated with NTG (1 mg/mL)under ultrasonicztion(200 W,50 kHz).A red mutant named Brevibacterium sp.DGCCN-25 showed higher and stable production of cholesterol oxidase was obtained.The enzyme activity was increased by 140%,it is 1.24 U/mL.Then dealed with DGCCN-25 using the same method,two revertants were obtained,one was white and the other was rose pink.The enzyme activity of two revertants was obvious decrease,they are 0.17 U/mL and 0.69 U/mL.The results showed the positive correlation between COD acticity and red pigment producing by Brevibacterium sp..The relativity model can be used as a method of screening for mutation and directed evolution.