A Program for assigning Secondary Structures in proteins

Path traversed by the CA atoms is used to devise a new method, ASSP (Assignment of Secondary Structure in Proteins), for the identification of secondary structure elements in proteins. ASSP is an extension of our in-house program HELANAL-Plus. The algorithm is based on the premise that the protein structure can be divided into continuous or uniform stretches, which can be defined in terms of geometrical parameters and depending on their values, the stretches can be classified into different SSEs, viz. α-helices, 310, π, PPII helices and strands. ASSP can provide a better understanding of the finer nuances of protein secondary structures. This web server version of ASSP uses JmolApplet to display the protein molecules.

The web server uses Jmol (Java applet) and hence the web browser must have latest JAVA installed and the Java applets enabled.

Example of assignment done by ASSP for Probable ribonucleoside-diphosphate reductase (PDB-ID: 3EE4)

For single PDB file:

Please enter 4 letter PDB-ID:

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Upload a file containing atomic coordinates in PDB file format:


For multiple PDB files: [maximum 10 files]

Please enter 4 letter PDB-IDs (seperated by comma(,)):

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Upload a file containing 4 letter PDB-ID codes (one per line):    Example File



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