Studies on the interaction and complexation of pyrrole compound with hemoglobin

Department of Chemistry, School of Basic and Applied Sciences, Career Point University,

Hamirpur-176 041, Himachal Pradesh, India

E-mail : sanjitmahato@gmail.com

Department of Chemical Engineering, College of Science, Engineering and Technology (CSET), University of South Africa (UNISA), South Africa

Department of Pharmaceutical Sciences & Technology, Birla Institute of Technology, Mesra,

Ranchi-835 215, Jharkhand, India

Physics Division, Department of Basic Sciences and Social Sciences, School of Technology,

North Eastern Hill University, Shillong-793 022, Meghalaya, India

E-mail : mrityunjoyphy@gmail.com

DST/CSIR Innovation Centre, National Centre for Nanostructured Materials,

CSIR Material Science and Manufacturing, Building-19B, PO Box 395, Pretoria-0001, South Africa

Currently Research Scientist at TCG Lifesciences Pvt. Ltd., Kolkata-700 091, India

Manuscript received 23 June 2017, accepted 15 July 2017

Alkaloids such as pyrrole, tetrapyrrole etc. are gaining intensive research importance due to its structural and conformational similarities with porphyrin and heme proteins as well as possess a great biological significance to the living systems. Herein, we have reported a detail investigation into the nature of interaction and complexation of a pyrrole compound, methyl-4-(2-oxo-2-phenyl-ethyl)-5-phenyl-1H-pyrrole-3- carboxylic acid methyl ester (PyS) with an important blood protein Hemoglobin (Hb). The spectroscopic and computer generated docking calculation have been applied in this study to understand the molecular interaction and complexation. Systematic concentration dependent studies of the Hb-PyS complex in solution phase using absorption, steady state/time resolved emission have been reported in this paper. A number of residues have been identified as the interaction zone for the PyS compound within the Hb protein such as heme group, tryptophan (Trp), tyrosine (Tyr) and amide group through π-π interaction and hydrogen bonding as evident from simultaneous experimental and docking results. This study may contribute to the basic understanding of the biological and medicinal potential of the pyrrole based pure substituted alkaloid.