Abstract:

Urease catalyzed hydrolysis of urea formed ammonium ions and carbonate ions. It has extensive application value. The strain of S. pasteurii ATCC11859 was screened through NTG (N\|methyl\|N″\|nitroso\|N\|nitrosoguanidine) mutation and a high yielding urease mutant was obtained. Among which strain B\|20 gave the highest urease activity of 28.37 mmol/min. This was increased 207% of the original strain. The strain inoculation amount and culture conditions of nitrogen source type were optimized. The results showed that the inoculation quantity was 10%, and using soybean meal as nitrogen source could achieve maximum urease activity as high as 32.9 mmol/min. This indicated that the technology is effective method for breeding high\|yield urease strain.

Key words: Sporosarcina pasteurii, urease, nitrosoguanidine(NTG), mutation breeding

摘要：

脲酶催化尿素的水解生成形成铵根离子和碳酸根离子，具有广泛的应用价值。以巴氏芽孢八叠球菌ATCC11859为出发菌株, 通过亚硝基胍诱变，得到高产脲酶突变株。其中菌株B\|20的脲酶活性最高，为28.4 mmol/min，较出发菌株提高了207%。对该菌株接种量、氮源种类培养条件进行优化，结果表明接种量为10%，且采用大豆粉为氮源时，脲酶活性最高为32.9 mmol/min。对脲酶高产菌株的选育表明该方法是一种行之有效的方法。

关键词: 巴氏芽孢八叠球菌；脲酶；亚硝基胍；诱变选育