Methylation-induced inactivation of restriction enzyme for amplified and signal-on electrochemiluminescence detection of methyltransferase activity

作者：Jiang, Bingying^*; Yang, Mengli; Yang, Cuiyun; Xiang, Yun^*; Yuan, Ruo

来源：Sensors and Actuators B: Chemical , 2017, 247: 573-579.

DOI：10.1016/j.snb.2017.02.148

• Methyltransferase
• Hybridization chain reaction
• Electrochemiluminescence
• DNAzyme
• Signal amplification

Sensitive detection of DNA methyltransferase (MTase) activity plays important roles for the diagnosis of many types of genetic disorder diseases and human malignancies. In this work, we describe the development of a label-free, sensitive and signal-on electrochemiluminescence (ECL) method for detecting MTase activity based on a restriction enzyme inactivation strategy. The sequence-specific double stranded DNA (dsDNA) probes on the sensing electrode can be cleaved by the restriction enzyme to initiate hybridization chain reaction (HCR) formation of the supersandwich DNAzyme structures, which catalyze the reduction and depletion of the dissolved oxygen to significantly quench the ECL of the oxygen/persulfate (O-2/S2O82-) system. The methylation of the dsDNA probes by DNA adenine methyltransferase (Dam MTase) can inactivate the restriction enzyme activity and inhibit subsequent HCR formation of the DNAzymes, leading to recovery of the ECL signal for signal-on detection of Dam MTase in a dynamic range from 0.01 U mL(-1) to 50 U mL(-1) with the detection limit of 6.4 x 10(-3) U mL(-1). The inhibition of Dam MTase activity by different drugs is also evaluated, offering this method new opportunity for highly sensitive detection of Dam MTase activity and for screening potential drugs for cancer therapy as well.

• 出版日期2017-8
• 单位重庆理工大学; 西南大学