title: A new search subspace to compensate failure of cavity-based localization of ligand-binding sites.
abstract: The common exercise adopted in almost all the ligand-binding sites (LBS) predictive methods is to considerably reduce the search space up to a meager fraction of the whole protein. In this exercise it is assumed that the LBS are mostly localized within a search subspace, cavities, which topologically appear to be valleys within a protein surface. Therefore, extraction of cavities is considered as a most important preprocessing step for finally predicting LBS. However, prediction of LBS based on cavity search subspace is found to fail for some proteins. To solve this problem a new search subspace was introduced which was found successful to localize LBS in most of the proteins used in this work for which cavity-based method MetaPocket 2.0 failed. Therefore this work appeared to augment well the existing binding site predictive methods through its applicability for complementary set of proteins for which cavity-based methods might fail. Also, to decide on the proteins for which instead of cavity-subspace the new subspace should be explored, a decision framework based on simple heuristic is made which uses geometric parameters of cavities extracted through MetaPocket 2.0. It is found that option for selecting the new or cavity-search subspace can be predicted correctly for nearly 87.5% of test proteins.
authors.affiliation: Department of Applied Science, Indian Institute of Information Technology, Indian Institute of Information Technology, Deoghat, Jhalwa, 211012, Allahabad, India. Electronic address: rs108@iiita.ac.in.
authors.forename: Kalpana
authors.initials: K
authors.lastname: Singh
authors.affiliation: Department of Applied Science, Indian Institute of Information Technology, Indian Institute of Information Technology, Deoghat, Jhalwa, 211012, Allahabad, India. Electronic address: tlahiri@iiita.ac.in.
authors.forename: Tapobrata
authors.initials: T
authors.lastname: Lahiri
mesh_terms: D001665:Binding Sites; D008024:Ligands; D011506:Proteins / Q000737:chemistry*
chemical_list: D008024:Ligands; D011506:Proteins
keywords: Alternative search subspace; Ligand-binding site localization; Protein atomic cluster roughness