Exploring the interaction of phenothiazinium dyes methylene blue, new methylene blue,azure A and azure B with tRNA Phe: spectroscopic, thermodynamic, voltammetric and molecular modeling approach
IR@IICB: CSIR-Indian Institute of Chemical Biology, Kolkata
View Archive Info| Field | Value | |
| Title |
Exploring the interaction of phenothiazinium dyes methylene blue, new methylene blue,azure A and azure B with tRNA Phe: spectroscopic, thermodynamic, voltammetric and molecular modeling approach
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| Creator |
Paul, Puja
Mati, Soumya Sundar Bhattacharya, Subhash Chandra Kumar, Gopinatha Suresh |
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| Subject |
Chemistry
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| Description |
This study focuses on the understanding of the interaction of phenothiazinium dyes methylene blue
(MB), new methylene blue (NMB), azure A (AZA) and azure B (AZB) with tRNAPhe with particular emphasis
on deciphering the mode and energetics of the binding. Strong intercalative binding to tRNAPhe was
observed for MB, NMB and AZB, bound by a partial intercalative mode. AZA has shown groove binding
characteristics. From spectroscopic studies binding affinity values of the order of 105 M�1 were deduced
for these dyes; the trend varied as MB 4 NMB 4 AZB 4 AZA. The binding was characterized by an
increase of thermal melting temperatures and perturbation in the circular dichroism spectrum of tRNA.
All the dyes acquired optical activity upon binding to tRNA. The binding was predominantly entropy
driven with a favorable enthalpy term that increased with temperature in all the cases. Dissection of the
Gibbs energy to polyelectrolytic and non-polyelectrolytic terms revealed a major role of the nonelectrostatic
forces in the binding. The small but significant heat capacity changes and the observed
enthalpy–entropy compensation phenomenon confirmed the involvement of multiple weak noncovalent
forces driving the interaction. The mode of binding was confirmed from quenching, viscosity and
cyclic voltammetric results. Using density functional theory, ground state optimized structures of the dyes
were calculated to provide insight into theoretical docking studies to correlate the experimental
approaches. The modeling results verified the binding location as well as the binding energy of
complexation. The results may provide new insights into the structure–activity relationship useful in the
design of effective RNA targeted therapeutic agents.
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| Date |
2017-03-07
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| Type |
Article
PeerReviewed |
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| Format |
application/pdf
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| Identifier |
http://www.eprints.iicb.res.in/2641/1/Phys._Chem._Chem._Phys_2017.pdf
Paul, Puja and Mati, Soumya Sundar and Bhattacharya, Subhash Chandra and Kumar, Gopinatha Suresh (2017) Exploring the interaction of phenothiazinium dyes methylene blue, new methylene blue,azure A and azure B with tRNA Phe: spectroscopic, thermodynamic, voltammetric and molecular modeling approach. PHYSICAL CHEMISTRY CHEMICAL PHYSICs, 19 (9). pp. 6636-6653. |
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| Relation |
http://dx.doi.org/10.1039/c6cp07888e
http://www.eprints.iicb.res.in/2641/ |
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