Isolation, Purification and Enzymatic Properties of Nuclease P1 Fermented by Penicillium citrinum
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摘要: 桔青霉(Penicillium citrinum)产核酸酶P1浓缩液采用活性炭脱色、硫酸铵分级沉淀、脱盐和凝胶层析等分离技术,得到核酸酶P1纯组分,并研究了该酶的酶学性质。该酶纯化后比酶活达到33967 U/mg,纯化倍数为8.48倍;该酶的米氏常数Km、最大反应速度Vm和催化常数Kcat分别为2.50 mmol/L、0.0864 mmol/(mL·min)和252.43 s−1。该酶最适温度为75 ℃,热稳定范围60~75 ℃;最适pH为5.5,pH稳定范围为4.0~6.0;Zn2+在1 mmol/L条件下对核酸酶P1有很好的激活作用,Cu2+和Co2+对该酶的抑制作用明显,而Ni2+、Fe2+、Mn2+等离子具有不同程度的抑制作用。本研究对于该酶的广泛应用奠定科学基础。Abstract: The nuclease P1 was purified to obtain pure component by activated carbon decolorization, (NH4)2SO4 precipitation, desalination and gel chromatography and its enzymatic properties was investigated. This purified enzyme had a specific activity of 33967 U/mg protein after 8.48-fold purification. The Michaelis constant (Km), the maximum reaction rates (Vm) and the catalytic constant (Kcat) of the purified enzyme were 2.50 mmol/L, 0.0864 mmol/(mL·min) and 252.43 s−1, respectively. The optimization pH and temperature for the nuclease P1 were at pH5.5 and 75 ℃. The enzyme was stable in the temperature range from 60 to 75 ℃ and in the pH range from 4.0 to 6.0. Zn2+ had a positive effect on the enzyme activity, while Cu2+ was a strong inhibitor of nuclease P1, Ni2+、Fe2+、Mn2+ had the different inhibition. This research laid a scientific foundation for the extensive application of the enzyme.
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Key words:
- nuclease P1 /
- purification /
- kinetic parameter /
- enzymatic property
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表 2 各分离步骤的纯化结果
Table 2. Purification result of each separation step
纯化过程样品 蛋白浓度
(mg/mL)蛋白总量
(g)比酶活
(U/mg)纯化倍数 浓缩酶液 3.64 3.458 4005 — 脱色酶液 2.85 2.28 10730 2.68 盐析 6.58 0.79 15157 3.78 脱盐 5.65 0.339 24262 6.06 凝胶层析 5.31 0.212 33967 8.48 表 1 不同浓度硫酸铵分级沉淀的比酶活
Table 1. The specific enzyme of (NH4)2SO4 fractionation
硫酸铵饱和度(%) 上清液蛋白(mg/mL) 沉淀溶解后蛋白(mg/mL) 上清液比酶活(U/mg) 沉淀比酶活(U/mg) 40 2.63 1.43 11984 1252 50 2.27 1.65 14194 7860 60 1.90 3.66 6733 11330 65 1.31 6.58 2532 15157 70 0.86 14.86 1732 9306 75 0.52 7.33 1418 7617 80 0.39 3.01 970 5782 85 0.22 0.97 457 988 -
[1] 王定昌. 核苷酸的生产技术及应用前景[J]. 粮油食品科技,2008,16(3):65−66. doi: 10.3969/j.issn.1007-7561.2008.03.024 [2] 喻晨, 赵劼, 张亚雄, 等. 桔青霉发酵制备核酸酶P1研究进展[J]. 食品工业科技,2010,31(11):416−420. [3] 张蕉南. 酵母核苷酸在水产动物上的研究进展与应用前景[J]. 饲料工业,2016,37(14):28−31. [4] Xiaoyi Chen, Bin Wang, Li Pan. Heterologous expression and characterization of Penicillium citrinum nuclease P1 in Aspergillus niger and its application in the preparation of nucleotides[J]. Protein Expression and Purification,2019(156):36−43. [5] Bai Zuhai, Chen Yan, Li Fei, et al. Electrochemical aptasensor for sulfadimethoxine detection based on the triggered cleavage activity of nuclease P1 by aptamer-target complex[J]. Talanta,2019(204):409−414. [6] 李兆飞, 姚娟, 余华顺, 等. 氯化锂-离子束复合诱变核酸酶P1高产菌株研究[J]. 食品科技,2013,38(12):2−4, 8. [7] 郑美娟, 郭金玲, 田毅红, 等. 桔青霉产核酸酶P1菌种高效选育方法研究[J]. 化学与生物工程,2018,35(2):33−37. doi: 10.3969/j.issn.1672-5425.2018.02.006 [8] 梁剑光, 顾秋忆, 秦修东, 等. 利用常压室温等离子体(ARTP)诱变选育高产核酸酶P1菌株[J]. 食品工业科技,2015,36(21):183−186. [9] 梁新乐, 孙隽, 张虹, 等. TB-DNA平板高效筛选桔青霉核酸酶P1产量突变株[J]. 中国食品学报,2012,12(9):103−108. [10] 廖明义. 产核酸酶P1菌株的诱变选育及发酵动力学研究[D]. 武汉: 华中农业大学, 2011: 34-35. [11] 廖明义, 陈雯莉. 桔青霉发酵制备核酸酶P1的发酵动力学研究[J]. 食品工业科技,2012,33(3):180−182, 316. [12] 田吕明, 叶炜, 赵劫, 等. 桔青霉摇瓶发酵生产核酸酶P1的动力学研究[J]. 工业微生物,2012,42(2):38−42. doi: 10.3969/j.issn.1001-6678.2012.02.008 [13] 田吕明, 叶炜, 赵劫, 等. 响应面法优化桔青霉产核酸酶P1培养基[J]. 食品科技,2011,36(10):23−27. [14] 喻晨, 张亚雄, 赵劫, 等. 响应面法优化桔青霉产核酸酶P1培养基[J]. 食品科学,2011,32(17):283−286. [15] 廖红东, 莫晓燕, 宋威, 等. 核酸酶P1的分离纯化及部分酶学性质研究[J]. 中国医药工业杂质,2005,36(9):536−538. [16] 吕浩, 应汉杰. 核酸酶P1的纯化和酶学性质研究[J]. 南京工业大学学报,2002,6(24):66−69. [17] 桂丽, 孙谧, 刘均忠, 等. 中性蛋白酶发酵液脱色工艺优化[J]. 食品与发酵工业,2016,42(8):92−96. [18] Y Guoqing, Lu E Shi, Yi Yu, et al. Production, purification and characterization of nuclease P1 from Penicilliun citrinum[J]. Process Biochemistry,2006,41:1276−1281. doi: 10.1016/j.procbio.2005.12.028 [19] 刘峄, 雷玲玲, 刘慧芹, 等. 2265FS土壤原位电导仪测定结果与土壤含盐量的关系[J]. 湖北农业科学,2014,53(13):3167−3169. doi: 10.3969/j.issn.0439-8114.2014.13.049 [20] 夏宁, 王晓琪, 严文冰, 等. 豆浆脂肪氧合酶测定方法的优化及酶动力学的研究[J]. 大豆科学,2018,37(5):769−775. [21] 胡晓倩, 陈雅蕙, 邓爱平, 等. 谷胱甘肽转硫酶酶促动力学实验设计[J]. 实验技术与管理,2002,19(1):27−31. doi: 10.3969/j.issn.1002-4956.2002.01.009 [22] Lineweaver H, Burke D. Determination of enzyme dissociation constants[J]. America Chemistry Society,1934,56(3):658−666. doi: 10.1021/ja01318a036 [23] 武林贺, 白新鹏, 吴谦, 等. 脂肪酶水解椰子油动力学研究[J]. 食品研究与开发,2016,37(16):65−69. doi: 10.3969/j.issn.1005-6521.2016.16.017 [24] 景一娴, 饶菁菁, 廖飞, 等. 低于米氏常数底物浓度下酶动力学参数的测定[J]. 重庆医科大学学报,2018,43(11):1464−1468. [25] Robert R Rando. Chemistry and enzymology of kcat Inhibitors[J]. Science,1974,185:320−324. doi: 10.1126/science.185.4148.320 [26] Robert Eisenthal, Michael J Danson, David W Hough. Catalytic effificiency and Kcat/Km: a useful comparator[J]. Trends in Biotechnology,2007,425(6):247−249. [27] 安扬东方. 阴沟肠杆菌海藻糖酶酶学性质鉴定及体外分子改良[D]. 武汉: 华中农业大学, 2017. -