Guanine-guided time-resolved luminescence recognition of DNA modification and i-motif formation by a terbium(III)-platinum(II) complex

Xiaohui Wang; Chengyuan Qian; Xiaoyong Wang; Tuanjie Li; Zijian Guo

doi:10.1016/j.bios.2019.111841

Guanine-guided time-resolved luminescence recognition of DNA modification and i-motif formation by a terbium(III)-platinum(II) complex

Biosens Bioelectron. 2020 Feb 15:150:111841. doi: 10.1016/j.bios.2019.111841. Epub 2019 Nov 4.

Authors

Xiaohui Wang¹, Chengyuan Qian², Xiaoyong Wang³, Tuanjie Li⁴, Zijian Guo⁵

Affiliations

¹ College of Chemistry and Molecular Engineering, Nanjing Tech University, Nanjing, 211816, PR China; State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210093, PR China. Electronic address: wangxhui@njtech.edu.cn.
² College of Chemistry and Molecular Engineering, Nanjing Tech University, Nanjing, 211816, PR China.
³ State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, State Key Laboratory of Analytical Chemistry for Life Science, Nanjing University, Nanjing, 210093, PR China. Electronic address: boxwxy@nju.edu.cn.
⁴ State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210093, PR China.
⁵ State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210093, PR China. Electronic address: zguo@nju.edu.cn.

PMID: 31735621
DOI: 10.1016/j.bios.2019.111841

Abstract

Site-specific recognition of DNA modification or the formation of noncanonical structures has important applications in molecular biology, disease diagnosis, and gene expression analysis. In this study, we introduce a guanine-guided sensing tool using a terbium(III)-platinum(II) complex (TPC) as a time-resolved luminescence probe to site-specifically recognize DNA modification and i-motif formation in aqueous solution. The probe is composed of a Tb^III center as the luminescent reporter and two Pt^II units as the receptor for guanine (G) nucleobase. TPC exhibits remarkable reaction selectivity for guanine nucleotides over other nucleotides, giving rise to a significant increase in luminescence. The luminescence enhancement of TPC is mainly attributed to an energy transfer from G base to the Tb^III center after the specific coordination of Pt^II with N7 of guanine (N7-G), which would be facilitated by the phosphates through promoting the departure of coordinated water and bringing G closer to Tb^IIIvia noncovalent interactions. Based on such sensing feature, the enhanced luminescence of TPC sensitized by G nucleotides can correspondingly decrease upon N7-G modifications of DNA or i-motif formation through constructing simple guanine-guided sensing tools. This probe would provide a useful strategy for site-specific recognition of DNA for extensive purposes.

Keywords: DNA modification; N7-guanine; Site-specific recognition; Terbium-platinum complex; Time-resolved luminescence probe; i-Motif.

MeSH terms

Biosensing Techniques*
Coordination Complexes / chemistry*
DNA / isolation & purification*
Guanine / chemistry
Nucleotide Motifs / genetics
Platinum / chemistry
Terbium / chemistry

Substances

Coordination Complexes
Terbium
Platinum
Guanine
DNA