Abstract
We have used electrospray ionization mass spectrometry (ESI-MS) and fluorescence and circular dichroism (CD) spectroscopy to explore the binding of ethidium bromide (EthBr) to non-self-complementary polythymine (polyT) strands in the absence and presence of Hg2+ ions. In the gas phase, ESI-MS revealed that Hg2+ ions have greater affinity, through T-Hg2+-T coordination, toward polyT strands than do other metal ions. These findings are consistent with our fluorescence and CD results obtained in solution; they revealed that more T33-EthBr-Hg2+ complexes existed upon increasing the concentrations of Hg2+ ions (from 0 to 50 μM). Surprisingly, the ESI-MS data indicated that the Hg2+ concentration dependence of the interaction between T33 and EthBr is biphasic. Our ESI-MS data revealed that the T33-EthBr-Hg2+ complexes formed with various stoichiometries depending on their relative concentrations of the components and the length of the DNA strand. When the concentrations of T33/EthBr/Hg2+ were 5/5/2.5 μM and 5/10/7.5 μM, 1:1:1 and 1:1:2 T33-EthBr-Hg2+ complexes were predominantly formed, respectively. Thus, Hg2+-induced DNA conformational changes clearly affect the interactions between DNA and EthBr.
| Original language | English |
|---|---|
| Pages (from-to) | 1834-1840 |
| Number of pages | 7 |
| Journal | Journal of the American Society for Mass Spectrometry |
| Volume | 20 |
| Issue number | 10 |
| DOIs | |
| Publication status | Published - 2009 Oct 1 |
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All Science Journal Classification (ASJC) codes
- Structural Biology
- Spectroscopy
Cite this
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Using Electrospray Ionization Mass Spectrometry to Explore the Interactions Among Polythymine Oligonucleotides, Ethidium Bromide, and Mercury Ions. / Chiang, Cheng Kang; Lin, Yang-Wei; Hu, Cho Chun; Chang, Huan Tsung.
In: Journal of the American Society for Mass Spectrometry, Vol. 20, No. 10, 01.10.2009, p. 1834-1840.Research output: Contribution to journal › Article
TY - JOUR
T1 - Using Electrospray Ionization Mass Spectrometry to Explore the Interactions Among Polythymine Oligonucleotides, Ethidium Bromide, and Mercury Ions
AU - Chiang, Cheng Kang
AU - Lin, Yang-Wei
AU - Hu, Cho Chun
AU - Chang, Huan Tsung
PY - 2009/10/1
Y1 - 2009/10/1
N2 - We have used electrospray ionization mass spectrometry (ESI-MS) and fluorescence and circular dichroism (CD) spectroscopy to explore the binding of ethidium bromide (EthBr) to non-self-complementary polythymine (polyT) strands in the absence and presence of Hg2+ ions. In the gas phase, ESI-MS revealed that Hg2+ ions have greater affinity, through T-Hg2+-T coordination, toward polyT strands than do other metal ions. These findings are consistent with our fluorescence and CD results obtained in solution; they revealed that more T33-EthBr-Hg2+ complexes existed upon increasing the concentrations of Hg2+ ions (from 0 to 50 μM). Surprisingly, the ESI-MS data indicated that the Hg2+ concentration dependence of the interaction between T33 and EthBr is biphasic. Our ESI-MS data revealed that the T33-EthBr-Hg2+ complexes formed with various stoichiometries depending on their relative concentrations of the components and the length of the DNA strand. When the concentrations of T33/EthBr/Hg2+ were 5/5/2.5 μM and 5/10/7.5 μM, 1:1:1 and 1:1:2 T33-EthBr-Hg2+ complexes were predominantly formed, respectively. Thus, Hg2+-induced DNA conformational changes clearly affect the interactions between DNA and EthBr.
AB - We have used electrospray ionization mass spectrometry (ESI-MS) and fluorescence and circular dichroism (CD) spectroscopy to explore the binding of ethidium bromide (EthBr) to non-self-complementary polythymine (polyT) strands in the absence and presence of Hg2+ ions. In the gas phase, ESI-MS revealed that Hg2+ ions have greater affinity, through T-Hg2+-T coordination, toward polyT strands than do other metal ions. These findings are consistent with our fluorescence and CD results obtained in solution; they revealed that more T33-EthBr-Hg2+ complexes existed upon increasing the concentrations of Hg2+ ions (from 0 to 50 μM). Surprisingly, the ESI-MS data indicated that the Hg2+ concentration dependence of the interaction between T33 and EthBr is biphasic. Our ESI-MS data revealed that the T33-EthBr-Hg2+ complexes formed with various stoichiometries depending on their relative concentrations of the components and the length of the DNA strand. When the concentrations of T33/EthBr/Hg2+ were 5/5/2.5 μM and 5/10/7.5 μM, 1:1:1 and 1:1:2 T33-EthBr-Hg2+ complexes were predominantly formed, respectively. Thus, Hg2+-induced DNA conformational changes clearly affect the interactions between DNA and EthBr.
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U2 - 10.1016/j.jasms.2009.06.009
DO - 10.1016/j.jasms.2009.06.009
M3 - Article
VL - 20
SP - 1834
EP - 1840
JO - Journal of the American Society for Mass Spectrometry
JF - Journal of the American Society for Mass Spectrometry
SN - 1044-0305
IS - 10
ER -