title: Dihedral angle and secondary structure database of short amino acid fragments.
abstract: Dihedral angles of amino acids are of considerable importance in protein tertiary structure prediction as they define the backbone of a protein and hence almost define the protein's entire conformation. Most ab initio protein structure prediction methods predict the secondary structure of a protein before predicting the tertiary structure because three-dimensional fold consists of repeating units of secondary structures. Hence, both dihedral angles and secondary structures are important in tertiary structure prediction of proteins. Here we describe a database called DASSD (Dihedral Angle and Secondary Structure Database of Short Amino acid Fragments) that contains dihedral angle values and secondary structure details of short amino acid fragments of lengths 1, 3 and 5. Information stored in this database was extracted from a set of 5,227 non-redundant high resolution (less than 2-angstroms) protein structures. In total, DASSD stores details for about 733,000 fragments. This database finds application in the development of ab initio protein structure prediction methods using fragment libraries and fragment assembly techniques. It is also useful in protein secondary structure prediction.
  
  
  BACKGROUND
  DASSD can be accessed and downloaded from http://www.cs.rmit.edu.au/dassd/
authors.affiliation: School of Computer Science and Information Technology, RMIT University, GPO Box 2474V, Melbourne 3001, Australia. sdayalan@cs.rmit.edu.au
authors.forename: Saravanan
authors.initials: S
authors.lastname: Dayalan
authors.forename: Nalaka Dilshan
authors.initials: ND
authors.lastname: Gooneratne
authors.forename: Savitri
authors.initials: S
authors.lastname: Bevinakoppa
authors.forename: Heiko
authors.initials: H
authors.lastname: Schroder