Neighbors Influence of Amino Acids and Secondary Structures
Update: February 2023
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Target Amino Acid Sequence

Secondary Structure

For secondary structure prediction use PsiPred



What is NIAS?

NIAS is a server to analyze the conformational preferences of amino acid residues in proteins. It is built using the Angle Probability List (APL), which represents the normalized frequency of observed pairs of amino acid residues and secondary structure in the Protein Data Bank. It combines the conformational preferences of amino acid residues (aa, torsion angles) in proteins with their secondary structure information (ss). A higher frequency associated with a pair of phi and psi angles indicates that this combination is more common in nature. The following Ramachandran maps show the conformational profile of Glycine residue when in coil, extended conformation and alpha helix secondary structure (APL1) according to the five structure databases considered by NIAS.


If you have any questions, please contact Prof. Dr. Marcio Dorn:

Citing NIAS

If you use NIAS in a scientific publication, we would appreciate citations to the following paper: