尿酸氧化酶高产菌筛选与酶学性质的研究

采用平板透明圈法和摇瓶发酵法筛选尿酸氧化酶高产菌株，并通过菌体形态特征和18S rDNA序列分析进行菌种鉴定。通过产酶发酵试验，优选产酶的最适条件；利用多种技术对尿酸氧化酶进行分离纯化，并通过酶促反应对酶学性质进行研究。结果表明，筛选获得1株尿酸氧化酶高产菌株UR-05，其被鉴定为食腺嘌呤芽生葡萄孢酵母（Blastobotrys adeninivorans）。菌株UR-05所产尿酸氧化酶分子质量约为41.5 kDa，比酶活为215.4 U/mg；该酶的最适温度为30 ℃、最适pH值为8.0；Mg2+和Na+对该酶有激活作用，K+、Ca2+、Mn2+、Zn2+对该酶有抑制作用。菌株UR-05所产尿酸氧化酶在一定条件范围内呈现出较强的活性，具有进一步研究及应用的价值。

Screening of high-yield urate oxidase strain and its enzymatic property

The high-yield urate oxidase strain was screened using plate transparent ring method and shaking flask fermentation test,and identified according to the morphological characteristics and 18S rDNA sequence analysis.The enzyme production conditions were optimized by fermentation test.The urate oxidase was isolated and purified by various techniques,and its enzymatic properties were further studied by enzymatic reaction.The results showed that a high-yield urate oxidase strain,namely as UR-05,was obtained and identified as Blastobotrys adeninivorans.The molecular mass of urate oxidase produced by strain UR-05 was about 41.5 kDa,the specific enzyme activity was 215.4 U/mg,and the optimal temperature and pH were 30℃and 8.0,respectively.Mg²⁺and Na+could activate the enzyme,while K⁺,Ca²⁺,Mn²⁺,and Zn²⁺inhibited the enzyme activity.The urate oxidase produced by strain UR-05 exhibited strong activity within a certain range of conditions,which had value for further research and application.