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›› 2007, Vol. 7 ›› Issue (6): 1207-1211.

• 生化工程专栏 • 上一篇    下一篇

Kitasatospora sp.MY 5-36中e-聚赖氨酸降解酶的纯化及酶学性质

冯小海,徐晓滢,姚忠,徐虹   

  1. 南京工业大学制药与生命科学学院
  • 出版日期:2007-12-20 发布日期:2007-12-20

Purification and Properties of e-Poly-L-lysine-degrading Enzyme from Kitasatospora sp. MY5-36

FENG Xiao-hai,XU Xiao-ying,YAO zhong,XU Hong   

  1. College of Life Science and Pharmacy, Nanjing University of Technology
  • Online:2007-12-20 Published:2007-12-20

摘要: 对Kitasatospora sp. MY 5-36中e-聚赖氨酸降解酶(PLD酶)进行了纯化和酶学性质研究. 通过DEAE-Sepharose, Source 15Q, Mono Q三步阴离子交换层析从细胞中得到纯酶,收率达40.7%,纯化倍数为500倍. 经SDS-PAGE电泳、凝胶过滤层析检测PLD酶由2个同聚亚基组成,亚基和全酶相对分子量分别为43.6和87.0 kDa. PLD酶的最适反应温度为30℃,最适pH值为7.0, 20~40℃保存时酶活力稳定,50~60℃保存时酶活力迅速下降,最大反应速率Vmax=0.112 mmol/(L×min), 米氏常数Km=0.216 mmol/L. PLD酶是一种金属酶,能够被Co2+激活、被Ca2+抑制.

关键词: e-聚赖氨酸降解酶(PLD酶), 阴离子交换层析, 酶学性质

Abstract: A e-poly-L-lysine-degrading (PLD) enzyme from Kitasatospora sp. MY5-36 was purified and characterized. The enzyme was purified through three steps of anion exchange chromatography including DEAE-Sepharose, Source 15Q and Mono Q. The overall purification multiple was 500 with an enzymatic activity recovery rate of 40.7%. As detected by SDS-PAGE and gel filtration chromatography, the PLD enzyme of this strain was composed of two homogeneous subunits. The molecular weight of subunit and holoenzymes were 43.6 and 87.0 kDa, respectively. Its optimal pH value was 7.0 and the optimal temperature 30℃. The activity of PLD enzyme was kept stable when the enzyme was conserved in the temperature range from 20 to 40℃, however, it declined rapidly in the temperature range from 50 to 60℃. The Km value was 0.216 mmol/L and the Vmax 0.112 mmol/(L×min). The PLD enzyme is a kind of metalloenzymes, and can be activated by Co2+ and inhibited by Ca2+.

Key words: e-poly-L-lysine-degrading enzyme, anion exchange chromatography, enzymological property