Anbu P
Department of Biological Engineering, Inha University, Incheon, South Korea.
Braz J Med Biol Res. 2016;49(4):e5178. doi: 10.1590/1414-431X20165178. Epub 2016 Mar 18.
A bacterial strain (PAP04) isolated from cattle farm soil was shown to produce an extracellular, solvent-stable protease. Sequence analysis using 16S rRNA showed that this strain was highly homologous (99%) to Brevibacillus laterosporus. Growth conditions that optimize protease production in this strain were determined as maltose (carbon source), skim milk (nitrogen source), pH 7.0, 40°C temperature, and 48 h incubation. Overall, conditions were optimized to yield a 5.91-fold higher production of protease compared to standard conditions. Furthermore, the stability of the enzyme in organic solvents was assessed by incubation for 2 weeks in solutions containing 50% concentration of various organic solvents. The enzyme retained activity in all tested solvents except ethanol; however, the protease activity was stimulated in benzene (74%) followed by acetone (63%) and chloroform (54.8%). In addition, the plate assay and zymography results also confirmed the stability of the PAP04 protease in various organic solvents. The organic solvent stability of this protease at high (50%) concentrations of solvents makes it an alternative catalyst for peptide synthesis in non-aqueous media.
从养牛场土壤中分离出的一株细菌（PAP04）被证明能产生一种细胞外、溶剂稳定的蛋白酶。使用16S rRNA进行的序列分析表明，该菌株与侧孢短芽孢杆菌高度同源（99%）。确定该菌株中蛋白酶产生的最佳生长条件为麦芽糖（碳源）、脱脂牛奶（氮源）、pH 7.0、温度40°C和培养48小时。总体而言，与标准条件相比，优化后的条件使蛋白酶产量提高了5.91倍。此外，通过在含有50%各种有机溶剂浓度的溶液中孵育2周来评估该酶在有机溶剂中的稳定性。除乙醇外，该酶在所有测试溶剂中均保持活性；然而，蛋白酶活性在苯中受到刺激（74%），其次是丙酮（63%）和氯仿（54.8%）。此外，平板测定和酶谱分析结果也证实了PAP04蛋白酶在各种有机溶剂中的稳定性。这种蛋白酶在高浓度（50%）溶剂中的有机溶剂稳定性使其成为非水介质中肽合成的替代催化剂。
