A 3D-RISM/RISM study of the oseltamivir binding efficiency with the wild-type and resistance-associated mutant forms of the viral influenza B neuraminidase

• Main Authors: Jiraphorn Phanich, Thanyada Rungrotmongkol, Daniel Sindhikara, Saree Phongphanphanee, Norio Yoshida, Fumio Hirata, Nawee Kungwan, Supot Hannongbua
• Format: Journal
• Published: 2018
• Subjects: Biochemistry, Genetics and Molecular Biology
• Online Access: https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=84959225426&origin=inward; http://cmuir.cmu.ac.th/jspui/handle/6653943832/55309
• Institution: Chiang Mai University

© 2015 The Protein Society. The binding affinity of oseltamivir to the influenza B neuraminidase and to its variants with three single substitutions, E119G, R152K, and D198N, is investigated by the MM/3D-RISM method. The binding affinity or the binding free energy of ligand to receptor was found to be determined by a subtle balance of two major contributions that largely cancel out each other: the ligand-receptor interactions and the dehydration free energy. The theoretical results of the binding affinity of the drug to the mutants reproduced the observed trend in the resistivity, measured by IC50; the high-level resistance of E119G and R152K, and the low-level resistance of D198N. For E119G and R152K, reduction of the direct drug-target interaction, especially at the mutated residue, is the main source of high-level oseltamivir resistance. This phenomenon, however, is not found in the D198N strain, which is located in the framework of the active-site.