CSIR Central

Structural-conformational aspects of tRNA complexation with chloroethyl nitrosourea derivatives: A molecular modeling and spectroscopic investigation

IR@NPL: CSIR-National Physical Laboratory, New Delhi

View Archive Info
 
 
Field Value
 
Title Structural-conformational aspects of tRNA complexation with chloroethyl nitrosourea derivatives: A molecular modeling and spectroscopic investigation
 
Creator Agarwal, Shweta
Tyagi, Gunjan
Chadha, Deepti
Mehrotra, Ranjana
 
Subject Biochemistry & Molecular Biology
Biophysics
 
Description Chloroethyl nitrosourea derivatives (CENUs) represent an important family of anticancer chemotherapeutic agents, which are used in the treatment of different types of cancer such as brain tumors, resistant or relapsed Hodgkin's disease, small cell lung cancer and malignant melanoma. This work focuses towards understanding the interaction of chloroethyl nitrosourea derivatives; lomustine, nimustine and semustine with tRNA using spectroscopic approach in order to elucidate their auxiliary anticancer action mechanism inside the cell. Attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR), Fourier transform infrared difference spectroscopy, circular dichroism spectroscopy and UV-visible spectroscopy were employed to investigate the binding parameters of tRNA-CENUs complexation. Results of present study demonstrate that all CENUs, studied here, interact with tRNA through guanine nitrogenous base residues and possibly further crosslink cytosine residues in paired region of tRNA. Moreover, spectral data collected for nimustine-tRNA and semustine-tRNA complex formation indicates towards the groove-directed-alkylation as their anti-malignant action, which involves the participation of uracil moiety located in major groove of tRNA. Besides this, tRNA-CENUs adduct formation did not alter the native conformation of biopolymer and tRNA remains in A-form after its interaction with all three nitrosourea derivatives studied. The binding constants (K-a) estimated for tRNA complexation with lomustine, nimustine and semustine are 2.55 x 10(2) M-1, 4.923 x 10(2) M-1 and 4.223 x 10(2) M-1 respectively, which specify weak type of CENU's binding with tRNA. Moreover, molecular modeling simulations were also performed to predict preferential binding orientation of CENUs with tRNA that corroborates well with spectral outcomes. The findings, presented here, recognize tRNA binding properties of CENUs that can further help in rational designing of more specific and efficient RNA targeted chemotherapeutic agents.
 
Publisher Elsevier B.V.
 
Date 2017-01
 
Type Article
PeerReviewed
 
Format application/pdf
 
Identifier http://npl.csircentral.net/2956/1/Structural-conformational%20aspects.pdf
Agarwal, Shweta and Tyagi, Gunjan and Chadha, Deepti and Mehrotra, Ranjana (2017) Structural-conformational aspects of tRNA complexation with chloroethyl nitrosourea derivatives: A molecular modeling and spectroscopic investigation. Journal of Photochemistry and Photobiology B: Biology, 166. pp. 1-11. ISSN 1011-1344
 
Relation http://npl.csircentral.net/2956/