引用本文: |
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涂楚桥,梁宏,王光辉.Cl-、NO3-和SO42-离子对漆酶催化活性的抑制作用[J].广西科学,1998,5(4):285-287,303. [点击复制]
- Tu Chuqiao,Liang Hong,Wang Guanghui.The Inhibition of Cl-、NO3- and SO42- Ions on Laccase-enzymatic Activity[J].Guangxi Sciences,1998,5(4):285-287,303. [点击复制]
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摘要: |
以5,6-二溴-2,3-二氰基氢醌为底物,在pH值4.50条件下,用分光光度法考察了Cl-、NO3-和SO42-离子对漆酶催化活性的影响。发现Cl-、NO3-和SO42-离子对漆酶的催化活性均有不同程度的抑制作用,其最大抑制率分别可达75%、31.4%和17.1%。动力学研究表明,Cl-、NO3-和SO42-离子的抑制作用是瞬时完成的,属于竞争性抑制过程,是通过与底物分子竞争漆酶分子中的Ⅱ型铜(Ⅱ)部位实现的。经测定,Cl-和NO3-离子与漆酶所形成的复合物其解离常数分别为1.12×10-4 mol·dm-3和1.78×10-3 mol·dm-3。 |
关键词: 漆树漆酶 阴离子 竞争性抑制作用 分光光度法 |
DOI: |
投稿时间:1998-06-25 |
基金项目:广西自然科学基金资助课题。 |
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The Inhibition of Cl-、NO3- and SO42- Ions on Laccase-enzymatic Activity |
Tu Chuqiao, Liang Hong, Wang Guanghui
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(Dept. of Chemistry, Guangxi Normal University, 3 Yucailu, Guilin, Guangxi, 541004) |
Abstract: |
The influence of Cl-、NO3- and SO42- ions on laccase-enzymatic activity was studied spectrophotometrically by 5,6-dibromo-2,3-dicyanohydroquinone (DDBQH2) under condition of pH4.50 and 30±0.1℃.The results showed that Cl-、NO3- and SO42- ions had obvious inhibition,and the inhibition ratio of theirs reached to 75%,31.4% and 17.1%,respectively;The kinetic studies demonstrated that the inhibitory actions of Cl-、NO3- and SO42- ions were time independent competitive type,and the inhibited position was the type 2 Cu(Ⅱ) site of laccase.The dissociation constants (Ki) of complexing reaction of Cl- and NO3- ions with type 2 Cu(Ⅱ) site of laccase are 112 and 1780 μmol·dm-3,respectively. |
Key words: Rhus vernicifera laccase anions competitive inhibition spectrophotometry |