产海洋细菌MP-2酯酶菌株的鉴定及酯酶理化性质的研究

Identification of MP-2 esterase producing marine Bacillus and study on properties of the esterase

中文关键词: 海洋地衣芽孢杆菌  酯酶  鉴定  性质

英文关键词: Marine  Bacillus licheniformis  Esterase  Identification  Characteristics

中文摘要:

      从渤海海泥样品中分离获得1株新型酯酶菌株，经鉴定为地衣芽孢杆菌Bacillus licheniformis。所得的MP-2酯酶的最适作用温度范围50～70 ℃，在60 ℃表现出了最高活性，属于耐热酶；最适作用pH为10，属于碱性酶，其pH值作用范围比较窄；具有良好的热稳定性；金属离子Co2+，Li+对酶具有激活作用，Ca2+ 对酯酶的活力没有显著影响，化学试剂SDS、EDTA及Tween 20对酯酶的抑制效果显著，对常见有机溶剂具有良好的耐受力；该酯酶对碳链长短不同的底物表现出不同的酶活。

英文摘要:

      A novel marine esterase-producing bacteria isolated from the Bohai Sea sediment was identified as Bacillus licheniformis. The MP-2 esterase was primarily purified and characterized. The optimal range of temperature of the esterase was 50～70 ℃, and the maximum activity was achieved at 60 ℃ and pH10.0. The esterase was alkaline and its optimum range of pH was narrow. The thermal stability of the esterase was good. Co2+，Li+ ions were found to activate the esterase, but Ca2+ had no significant effects on the activity of the esterase. While SDS，EDTA and Tween-20 had significantly suppressive effects on the esterase. It showed strong resistance to ordinary organic solvents. The enzyme exhibited different esterase activities towards substrates with different length of carbon chains.