Exploring the binding mechanism between methylene blue and ovalbumin using spectroscopic analyses and computational simulations

Abstract

The detailed investigation of methylene blue (MB) dye with ovalbumin (OVA) was examined by multispectroscopic and computational techniques. The experimental results of emission spectral studies displayed that the quenching behaviour of OVA with MB dye is due to static quenching mechanism. Isothermal titration calorimetry experimental results suggested that the binding of MB dye became favoured with the aid of a favourable entropy contribution and negative enthalpy. The absorption and circular dichroism spectral experiments showed that the binding of MB dye prompted conformational modifications to the secondary structure of OVA protein. The computational studies have been used to predict the binding region and the stability of MB in OVA protein.

Communicated by Ramaswamy H. Sarma

Keywords:

• Emission spectroscopy
• methylene blue
• molecular docking
• molecular dynamics simulations
• ovalbumin

Acknowledgement

P.M. Finland gratefully acknowledges the Sigrid Jusélius Foundation, Joe, Pentti and Tor Borg Memorial Fund for computational and laboratory infrastructure, bioinformatics infrastructure facility supported by Biocenter Finland, CSC-IT Center for Science (Project: 2000461) for computational facility, Dr. Jukka Lehtonen for the IT support, and specially thanks Prof. Mark Johnson, SBL, Åbo Akademi University, for providing the lab facility.

Disclosure statement

The authors declare no conflict of interest.

Additional information

Funding

This work was supported by Science and Engineering Research Board, Government of India for National Postdoctoral Fellowship Scheme (PDF/2017/001353 dated: 11.07.2017), University grants commission (UGC-MRP, Project No. 41-309/2012 (SR)) and Department of Science and Technology (DST-SERB, Project no. SR/FT/CS-015/2009), India, for the financial support.