title: Lysozyme binding ability toward psychoactive stimulant drugs: Modulatory effect of colloidal metal nanoparticles.
abstract: The interaction and binding behavior of the well-known psychoactive stimulant drugs theophylline (THP) and theobromine (THB) with lysozyme (LYS) was monitored by in-vitro fluorescence titration and molecular docking calculations under physiological condition. The quenching of protein fluorescence on addition of the drugs is due to the formation of protein-drug complex in the ground state in both the cases. However, the binding interaction is almost three orders of magnitude stronger in THP, which involves mostly hydrogen bonding interaction in comparison with THB where hydrophobic binding plays the predominant role. The mechanism of fluorescence quenching (static type) remains same also in presence of gold and silver nanoparticles (NPs); however, the binding capacity of LYS with the drugs changes drastically in comparison with that in aqueous buffer medium. While the binding affinity of LYS to THB increases ca. 100 times in presence of both the NPs, it is seen to decrease drastically (by almost 1000 fold) for THP. This significant modulation in binding behavior indicates that the drug transportation capacity of LYS can be controlled significantly with the formation protein-NP noncovalent assembly system as an efficient delivery channel.
authors.affiliation: Centre for Advanced Studies, Department of Chemistry, North-Eastern Hill University, Shillong, 793 022, India.
authors.forename: Vikash K
authors.initials: VK
authors.lastname: Sonu
authors.affiliation: Centre for Advanced Studies, Department of Chemistry, North-Eastern Hill University, Shillong, 793 022, India.
authors.forename: Mullah Muhaiminul
authors.initials: MM
authors.lastname: Islam
authors.affiliation: Centre for Advanced Studies, Department of Chemistry, North-Eastern Hill University, Shillong, 793 022, India.
authors.forename: Mostofa Ataur
authors.initials: MA
authors.lastname: Rohman
authors.affiliation: Centre for Advanced Studies, Department of Chemistry, North-Eastern Hill University, Shillong, 793 022, India. Electronic address: smitra@nehu.ac.in.
authors.forename: Sivaprasad
authors.initials: S
authors.lastname: Mitra
mesh_terms: D000818:Animals; D001665:Binding Sites; D002645:Chickens; D003102:Colloids / Q000737:chemistry*; D005453:Fluorescence; D006046:Gold / Q000737:chemistry; D006860:Hydrogen Bonding; D057927:Hydrophobic and Hydrophilic Interactions; D053768:Metal Nanoparticles / Q000008:administration & dosage* / Q000737:chemistry; D062105:Molecular Docking Simulation; D009113:Muramidase / Q000737:chemistry / Q000378:metabolism*; D011485:Protein Binding; D012834:Silver / Q000737:chemistry; D013050:Spectrometry, Fluorescence; D013805:Theobromine / Q000737:chemistry / Q000378:metabolism*; D013806:Theophylline / Q000737:chemistry / Q000378:metabolism*; D014665:Vasodilator Agents / Q000737:chemistry / Q000378:metabolism*
chemical_list: D003102:Colloids; D014665:Vasodilator Agents; D012834:Silver; D006046:Gold; D013806:Theophylline; D009113:Muramidase; D013805:Theobromine
keywords: Colloidal nanoparticles; Fluorescence quenching; Hydrophobic & hydrogen bonding interaction; Lysozyme; Molecular docking; Theobromine; Theophylline