AMP脱氨酶的生化性质研究

主要从底物浓度、温度、pH和常见离子等方面对相对分子量56ku左右的腺苷酸脱氨酶的催化作用的影响因素进行研究。通过酶的催化实验,结果表明:原始底物质量浓度为2.78×10-2g/L、温度为37℃、pH为5.9时,AMP脱氨酶催化活性最好,IMP的转化速度最高为1.965×10-2mol/min。同时考察了Cu2+、Fe2+、Al3+、Mn2+、Na+、Mg2+、Zn2+等阳离子和SO42-、Cl-、NO3-、CO32-、H2PO4-、B4O72-、柠檬酸根、EDTA离子等阴离子对AMP脱氨酶催化能力的影响。结果表明:柠檬酸根离子和Mn2+对AMP脱氨酶有明显激活性影响,其他离子浓度超过0.01mol/L时对AMP脱氨酶一般有抑制性影响,AMP脱氨酶商品酶在常温干燥状态下稳定性很好,4℃存放的酶液半衰期为5.5d。

Study on the biochemical characteristics of AMP deaminase

The effects of the substrate concentration,temperature,pH value,and the other common ion on the catalytic action of Adenosine Deaminase with about 56ku molecular weight were studied.The best catalytic conditions such as the substrate concentration 2.78×10-2g/L,temperature 37℃,and pH value 5.9 were obtained,which the highest catalytic conversion rate was 1.965×10-2mol/min.Meanwhile,Cu2+,Fe2+,Al3+,Mn2+,Na+,Mg2+,Zn2+ and SO42-,Cl-,NO3-,CO32-,H2PO4-,B4O72-,lemon acid radical,EDTA ion were found having a certain influence to the AMP deaminase.The result showed that lemon acid radical ion and Mn2+ had an obviously activated influence on AMP deaminase,but the other ion concentration surpass 0.01mol/L generally had an inhibitory effect on AMP deaminase and the AMP deaminase powder had a good stability quality under atmospheric temperature in dry condition and the half-life of enzyme solution was 5.5 days at 4℃.