recombinant enzyme was purified to homogeneity. The enzyme showed maximum activity at pH 7.5 and 55°C and was stable between pH 5.0 and 10.5, and at temperatures up to 45°C. The Km and Vmax values of thiourocanate hydratase towards thiourocanic acid were 30 μM and 7.1 μmol/min/mg, respectively. The enzyme was strongly inhibited by CuCl2 and HgCl2. The amino acid sequence of the enzyme showed 46% identity
从利用麦角硫氨酸的菌株Burkholderia sp。分离到一种新型酶硫脲尿酸水合酶,该酶催化硫脲尿酸转化为3-(5-氧代-2-硫代氧杂咪唑啉丁-4-基)丙酸。HME13。当在含有麦角硫因作为唯一氮源的培养基中培养HME13细胞时,在细胞粗提物中检测到硫代尿烷酸酯的代谢活性。但是,在Luria-Bertani培养基中培养的HME13细胞的粗提物中未检测到活性。克隆编码硫代尿烷酸酯水合酶的基因并在大肠杆菌中表达,并将重组酶纯化至均一。该酶在pH 7.5和55°C下显示最大活性,在pH 5.0和10.5之间以及最高45°C的温度下稳定。硫代尿酸水合酶对硫代尿酸的Km和Vmax值分别为30μM和7.1μmol/ min / mg。该酶被CuCl2和HgCl2强烈抑制。该酶的氨基酸序列与恶臭假单胞菌(Pseudomonas putida)的尿素酶具有46%的同一性,但是硫代尿素水合酶没有尿素酶活性。