PDB Goodies is a web‐based graphical user interface (GUI) to manipulate the Protein Data Bank file containing the three‐dimensional atomic coordinates of protein structures. The program also allows users to save the manipulated three‐dimensional atomic coordinate file on their local client system. These fragments are used in various stages of structure elucidation and analysis. This software is incorporated with all the three‐dimensional protein structures available in the Protein Data Bank, which presently holds approximately 18 000 structures. In addition, this program works on a three‐dimensional atomic coordinate file (Protein Data Bank format) uploaded from the client machine. The program is written using CGI/PERL scripts and is platform independent. The program PDB Goodies can be accessed over the World Wide Web at http://144.16.71.11/pdbgoodies/.

SSEP is a comprehensive resource for accessing information related to the secondary structural elements present in the 25 and 90% non-redundant protein chains. The database contains 1771 protein chains from 1670 protein structures and 6182 protein chains from 5425 protein structures in 25 and 90% non-redundant protein chains, respectively. The current version provides information about the alpha-helical segments and beta-strand fragments of varying lengths. In addition, it also contains the information about 3(10)-helix, beta- and nu-turns and hairpin loops. The free graphics program RASMOL has been interfaced with the search engine to visualize the three-dimensional structures of the user queried secondary structural fragment. The database is updated regularly and is available through Bioinformatics web server at http://cluster.physics.iisc.ernet.in/ssep/ or http://144.16.71.148/ssep/.

Transmembrane Helices in Genome Sequences (THGS) is an interactive web-based database, developed to search the transmembrane helices in the user-interested gene sequences available in the Genome Database (GDB). The proposed database has provision to search sequence motifs in transmembrane and globular proteins. In addition, the motif can be searched in the other sequence databases (Swiss-Prot and PIR) or in the macromolecular structure database, Protein Data Bank (PDB). Further, the 3D structure of the corresponding queried motif, if it is available in the solved protein structures deposited in the Protein Data Bank, can also be visualized using the widely used graphics package RASMOL. All the sequence databases used in the present work are updated frequently and hence the results produced are up to date. The database THGS is freely available via the world wide web and can be accessed at http:// pranag.physics.iisc.ernet.in/thgs/ or http://144.16. 71.10/thgs/.

An interactive web-based display tool, Biomolecules Segment Display Device (BSDD), has been developed to search for and visualize a user-defined motif or fragment among the protein structures available in the Protein Data Bank (PDB). In addition, the tool works for the structures available in a selected sub-set of non-homologous protein structures (25% and 90% sequence identity). The graphics package RASMOL has been incorporated as an interface to visualize the three-dimensional structure of the user-defined motif. In addition, the software can be used to extract the atomic coordinates of the required fragment and save them to the client system. The atomic coordinates are updated every week from the RCSB-PDB server, and hence the results produced by BSDD are up to date at any given time. The software BSDD is available over the World Wide Web at http://iris.physics.iisc.ernet.in/bsdd or http://144.16.71.2/bsdd.

In the fields of chemical graph theory and mathematical chemistry, a topological index also known as a connectivity index is a type of a molecular descriptor that is calculated based on the molecular graph of a chemical compound. Topological indices are numerical parameters of a graph. Topological indices are used for example in the development of quantitative structure-activity relationships (QSARs) and other properties of molecules are correlated with their chemical structure, in that Silicates are the most common minerals in the Earth’s crust and mantle, it has a wide variety of physical properties which paved way to find the topological indices. In this paper gives us the generalized new form of topological indices such as Arithmetic-Geometric Index (AG Index), SK Index, SK1 Index and SK2 Index of Silicate network graphs.