Research Article Biophysical Insight into the Interaction of Human Lysozyme with Anticancer Drug Anastrozole: A Multitechnique Approach Fahad M. Almutairi , 1 Mohammad Rehan Ajmal , 1 Adel Ibrahim Al Alawy, 1 Rizwan Hasan Khan , 2 and Ali Saber Abdelhameed 3 1 Physical Biochemistry Research Laboratory, Biochemistry Department, Faculty of Science, University of Tabuk, P.O. Box 741, Tabuk 71491, Saudi Arabia 2 Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh, India 3 Faculty of Pharmacy, King Saud University, Riyadh, Saudi Arabia Correspondence should be addressed to Fahad M. Almutairi; falrabae@ut.edu.sa and Mohammad Rehan Ajmal; ajmal.rehan@ rediffmail.com Received 26 February 2020; Accepted 19 June 2020; Published 25 August 2020 Academic Editor: Aggelos Avramopoulos Copyright © 2020 Fahad M. Almutairi et al. is is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. In the present study, we employ fluorescence spectroscopy, dynamic light scattering, and molecular docking methods. Binding of anticancer drug anastrozole with human lysozyme (HL) is studied. Binding of anastrozole to HL is moderate but spontaneous. ere is anastrozole persuaded hydrodynamic change in HL, leading to molecular compaction. Binding of anastrozole to HL also decreased in vitro lytic activity of HL. Molecular docking results suggest the electrostatic interactions and van der Waals forces played key role in binding interaction of anastrozole near the catalytic site. Binding interaction of anastrozole to proteins other than major transport proteins in blood can significantly affect pharmacokinetics of this molecule. Hence, rationalizing drug dosage is important. is study also points to unrelated effects that small molecules bring in the body that are considerable and need thorough investigation. 1. Introduction Small ligands are known to intermingle with protein molecules readily [1, 2]. Protein-drug interaction studies are important and central in understanding biological processes. Recently, such studies are hot spots of mul- tidisciplinary research [3, 4]. Drug binding to transport proteins can significantly affect metabolism of drug molecules. Proteins are versatile molecules and perform many different functions in the human body. Human lysozyme (HL) is a small globular protein. HL is found in secretions such as saliva and tears. It is a model protein [5, 6]. Ever since its discovery, lysozyme represented a prototype molecule for understanding the complexity of the protein structure and function [7]. us, the study on the interaction of drugs with lysozyme has important significance. Such studies are useful for providing information on the structural features of the proteins on interaction with drugs and to illuminate the therapeutic effectiveness of drugs [8, 9]. Human lysozyme (HL) is an important enzyme and is part of the body defense against many bacteria. HL is found in tears and saliva [10]. It is a single polypeptide comprising of seven helices and one beta sheet. ere are no subunits or prosthetic groups. HL hydrolyze β-1,4-glycosidic linkages between N-ace- tylmuramic acid and N-acetylglucosamine; these linkages are present in the peptidoglycan cell wall of bacteria [11]. HL causes damage to the bacterial cell wall by degrading thepolymer,leadingtoperforationandbacterialcelllyses [12]. e active site is easily visible in three-dimensional models. Hydrolysis of the cell wall of bacteria is an im- portant component of antimicrobial action of HL [7]. Asp 53 and Glu 35 are main residues involved in activity [13] while many others are involved in holding ligands to Hindawi e Scientific World Journal Volume 2020, Article ID 8363685, 7 pages https://doi.org/10.1155/2020/8363685