A colorimetric assay of DNA methyltransferase activity based on peroxidase mimicking of DNA template Ag/Pt bimetallic nanoclusters
DNA methylation catalyzed by DNA methyl transferase (MTase) is a significant epigenetic process for modulating gene expression. Abnormal levels of DNA MTase enzyme have been regarded as a cancer biomarker or a sign of bacterial diseases. We developed a novel colorimetric method to assay M.SssI MTase activity employing peroxidase-like activity of DNA template Ag/Pt NCs without using restriction enzymes. Based on inhibiting the peroxidase reaction that occurred in the TMB-H2O2 system, in the presence of MTase, a highly sensitive and selective colorimetric biosensor was fabricated with a detection limit (LOD) of 0.05 U/mL and a linear range from 0.5 to 10 U/mL. The changes in absorption intensity were monitored to quantify the M.SssI activity. This strategy had a high selectivity over other proteins. Furthermore, it is also demonstrated that this method can be used for the evaluation and screening of inhibitors for DNA MTase.
KeywordsAg/Pt nanoclusters DNA methyltransferase Colorimetric detection Enzyme mimic
The authors thank the research Council of University of Tehran (Grant 28645/01/02) for financial support of this work.
Compliance with ethical standards
Conflict of interest
The authors declare that they have no competing interests.
- 6.Mutze K, Langer R, Schumacher F, Becker K, Ott K, Novotny A, et al. DNA methyltransferase 1 as a predictive biomarker and potential therapeutic target for chemotherapy in gastric cancer. Eur J Cancer. 2011, 47:1817–25.Google Scholar
- 12.Myrnes B, Norstrand K, Giercksky KE, Sjunneskog C, Krokan H. A simplified assay for O6 -methylguanine-DNA methyltransferase activity and its application to human neoplastic and non-neoplastic tissues. Carcinogenesis. 1984:1061–1064Google Scholar
- 13.Zou D, Zhang D, Liu S, Zhao B, Wang H. Interplay of binding stoichiometry and recognition specificity for the interaction of MBD2b protein and methylated DNA revealed by affinity capillary electrophoresis coupled with laser-induced fluorescence analysis. Anal Chem. 2014;86:1775–82.CrossRefPubMedGoogle Scholar
- 35.Liu T, Zhao J, Zhang D, Li G (2010) Novel method to detect DNA methylation using gold nanoparticles coupled with enzyme-linkage reactions. Anal Chem 82:229–233Google Scholar
- 42.Zhang S, Wang K, Li K. B, Shi W, Jia WP, Chen X, Sun T, Han DM (2017) A DNA-stabilized silver nanoclusters/graphene oxide-based platform for the sensitive detection of DNA through hybridization chain reaction. Biosens Bioelectron 91:374–379Google Scholar
- 45.Liu W, Lai H, Huang R, Zhao C, Wang Y, Weng X, Zhou X (2015) DNA methyltransferase activity detection based on fluorescent silver nanocluster hairpin-shaped DNA probe with 5’-C-rich/G-rich-3’ tails. Biosens Bioelectron 68:736–7740Google Scholar
- 57.Xing XW, Tang F, Wu J, Chu JM, Feng YQ, Zhou X, Yuan BF (2014) Sensitive detection of DNA methyltransferase activity based on exonuclease-mediated target recycling. Anal Chem 86:11269-11274.Google Scholar