title: Delineating the role of ionic interactions in structural and functional integrity of B. malayi Guanylate kinase.
abstract: The present work deals with investigating the role of ionic interactions in the native conformation of BmGK by altering pH and salt concentration as well as by disruption of inter-subunit region. The study on structural and functional properties of BmGK as a function of pH showed that the secondary and tertiary elements of the protein were disturbed at low pH with loss of its native oligomerization and functional activity. High concentration of NaCl also changed the native conformation of BmGK with dissociation of its dimeric form. We also mutated dimeric interface of BmGK and identified intersubunit residues, Arg105 and Glu140, essential for dimer stability as double mutation at both positions hinders dimerization. The quaternary structure is found to be essential for full enzymatic activity and stability. In vitro results were supported by in silico molecular dynamics simulation studies through conformational stability analysis. Thus, the work carried out points toward new approach of targeting dimeric interface of BmGK in lieu of its similar active site region to its counterpart human enzyme. This may lead to the design of inhibitors targeted to key parasitic enzyme (BmGK) specifically.
authors.affiliation: Division of Biochemistry, CSIR-Central Drug Research Institute, Lucknow, 226031, Uttar Pradesh, India.
authors.forename: Smita
authors.initials: S
authors.lastname: Gupta
authors.affiliation: Computer Aided Drug Design and Molecular Modeling Lab., Department of Bioinformatics, Alagappa University, Karaikudi, Tamilnadu, India.
authors.forename: Venkatesan
authors.initials: V
authors.lastname: Suryanarayanan
authors.affiliation: Division of Biochemistry, CSIR-Central Drug Research Institute, Lucknow, 226031, Uttar Pradesh, India.
authors.forename: Sunita
authors.initials: S
authors.lastname: Yadav
authors.affiliation: Computer Aided Drug Design and Molecular Modeling Lab., Department of Bioinformatics, Alagappa University, Karaikudi, Tamilnadu, India.
authors.forename: Sanjeev K
authors.initials: SK
authors.lastname: Singh
authors.affiliation: Division of Biochemistry, CSIR-Central Drug Research Institute, Lucknow, 226031, Uttar Pradesh, India. Electronic address: jkscdri@yahoo.com.
authors.forename: Jitendra K
authors.initials: JK
authors.lastname: Saxena
mesh_terms: D000818:Animals; D017178:Brugia malayi / Q000201:enzymology*; D004305:Dose-Response Relationship, Drug; D004795:Enzyme Stability / Q000187:drug effects; D051528:Guanylate Kinases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D056004:Molecular Dynamics Simulation; D016297:Mutagenesis, Site-Directed; D009154:Mutation; D009994:Osmolar Concentration; D055503:Protein Multimerization / Q000187:drug effects; D020836:Protein Structure, Quaternary / Q000187:drug effects; D017433:Protein Structure, Secondary / Q000187:drug effects; D012965:Sodium Chloride / Q000494:pharmacology
chemical_list: D012965:Sodium Chloride; D051528:Guanylate Kinases
keywords: BmGK; Intersubunit interactions; pH