title: An In Silico study of TiO2nanoparticles interaction with twenty standard amino acids in aqueous solution.
abstract: Titanium dioxide (TiO2) is probably one of the most widely used nanomaterials, and its extensive exposure may result in potentially adverse biological effects. Yet, the underlying mechanisms of interaction involving TiO2NPs and macromolecules, e.g., proteins, are still not well understood. Here, we perform all-atom molecular dynamics simulations to investigate the interactions between TiO2NPs and the twenty standard amino acids in aqueous solution exploiting a newly developed TiO2force field. We found that charged amino acids play a dominant role during the process of binding to the TiO2surface, with both basic and acidic residues overwhelmingly preferred over the non-charged counterparts. By calculating the Potential Mean Force, we showed that Arg is prone to direct binding onto the NP surface, while Lys needs to overcome a ~2 kT free energy barrier. On the other hand, acidic residues tend to form "water bridges" between their sidechains and TiO2surface, thus displaying an indirect binding. Moreover, the overall preferred positions and configurations of different residues are highly dependent on properties of the first and second solvation water. These molecular insights learned from this work might help with a better understanding of the interactions between biomolecules and nanomaterials.
authors.affiliation: School for Radiological and Interdisciplinary Sciences (RAD-X) and Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions, Soochow University, Suzhou, 215123, China.
authors.forename: Shengtang
authors.initials: S
authors.lastname: Liu
authors.affiliation: School for Radiological and Interdisciplinary Sciences (RAD-X) and Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions, Soochow University, Suzhou, 215123, China.
authors.forename: Xuan-Yu
authors.initials: XY
authors.lastname: Meng
authors.affiliation: Computational Biological Center, IBM Thomas J. Watson Research Center, Yorktown Heights, NY 10598, USA.
authors.forename: Jose Manuel
authors.initials: JM
authors.lastname: Perez-Aguilar
authors.affiliation: School for Radiological and Interdisciplinary Sciences (RAD-X) and Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions, Soochow University, Suzhou, 215123, China.|Computational Biological Center, IBM Thomas J. Watson Research Center, Yorktown Heights, NY 10598, USA.|Department of Chemistry, Columbia University, New York, NY 10027, USA.
authors.forename: Ruhong
authors.initials: R
authors.lastname: Zhou
mesh_terms: D000596:Amino Acids / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry*; D056004:Molecular Dynamics Simulation; D012996:Solutions / Q000737:chemistry*; D014025:Titanium / Q000737:chemistry*; D014867:Water / Q000737:chemistry*
chemical_list: D000596:Amino Acids; D012996:Solutions; D014867:Water; C009495:titanium dioxide; D014025:Titanium