从高温土壤中分离得到的一株产耐热中性蛋白酶的嗜热芽孢杆菌,该菌分泌的胞外蛋白酶粗酶液经80%饱和度硫酸铵沉淀、DEAE-Sepharose Fast Flow阴离子交换层析和Superdax75凝胶层析分离纯化后,纯化倍数提高4．36倍,得率为5．3%,经SDS-PAG...从高温土壤中分离得到的一株产耐热中性蛋白酶的嗜热芽孢杆菌,该菌分泌的胞外蛋白酶粗酶液经80%饱和度硫酸铵沉淀、DEAE-Sepharose Fast Flow阴离子交换层析和Superdax75凝胶层析分离纯化后,纯化倍数提高4．36倍,得率为5．3%,经SDS-PAGE电泳测得其分子量为30．6kDa。酶的最适温度与pH实验表明,该酶最适温度为65℃、最适pH为7．5,并且该酶在50℃时表现出1h以上的稳定性。该蛋白酶的活性受到丝氨酸族蛋白酶专一性抑制PMSF和金属离子螯合剂EDTA强烈抑制,Zn^(2+)能提高酶活性,因此该蛋白酶为Zn^(2+)激活的丝氨酸族蛋白酶。展开更多
4-Hydroxybenzoate （4HBA） is a naturally occurring aromatic compound, as a key intermediate metabolite not only for natural products but also for arti- ficial products. There are four metabolic pathways for 4HBA： pr...4-Hydroxybenzoate （4HBA） is a naturally occurring aromatic compound, as a key intermediate metabolite not only for natural products but also for arti- ficial products. There are four metabolic pathways for 4HBA： protocatechuate cleavage pathway; catechol cleavage pathway; anaerobic degradation pathway in anaerobes ; and gentisate cleavage pathway. The last pathway including a NIH shift reaction remains to be elucidated. In this review we emphasized on the NIH shift reaction involved in the 4HBA degrdation. The key enzymes of each 4HBA metabolic pathway also were introduced. Finnaly, we described the thermophilic Bacillus sp. B1 strain which was capable of degrading varous aromatic compounds including gHBA, and presented a direction for the research of NIH shift reaction.展开更多
文摘从高温土壤中分离得到的一株产耐热中性蛋白酶的嗜热芽孢杆菌,该菌分泌的胞外蛋白酶粗酶液经80%饱和度硫酸铵沉淀、DEAE-Sepharose Fast Flow阴离子交换层析和Superdax75凝胶层析分离纯化后,纯化倍数提高4．36倍,得率为5．3%,经SDS-PAGE电泳测得其分子量为30．6kDa。酶的最适温度与pH实验表明,该酶最适温度为65℃、最适pH为7．5,并且该酶在50℃时表现出1h以上的稳定性。该蛋白酶的活性受到丝氨酸族蛋白酶专一性抑制PMSF和金属离子螯合剂EDTA强烈抑制,Zn^(2+)能提高酶活性,因此该蛋白酶为Zn^(2+)激活的丝氨酸族蛋白酶。
基金Supported by the National Natural Science Foundation of China(31400099)Jiangsu Science and Technology Agency Project(BK20141148 and BK20140235)Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)
文摘4-Hydroxybenzoate （4HBA） is a naturally occurring aromatic compound, as a key intermediate metabolite not only for natural products but also for arti- ficial products. There are four metabolic pathways for 4HBA： protocatechuate cleavage pathway; catechol cleavage pathway; anaerobic degradation pathway in anaerobes ; and gentisate cleavage pathway. The last pathway including a NIH shift reaction remains to be elucidated. In this review we emphasized on the NIH shift reaction involved in the 4HBA degrdation. The key enzymes of each 4HBA metabolic pathway also were introduced. Finnaly, we described the thermophilic Bacillus sp. B1 strain which was capable of degrading varous aromatic compounds including gHBA, and presented a direction for the research of NIH shift reaction.
