PSAweb is a web server, developed to analyze the amino acid sequence and multiple sequence alignment of proteins. This is a comprehensive on-line Internet tool that allows the rapid visualization of an analysis, by output in GIF format. It assists the user in analyzing and presenting the primary structure of proteins and mutiple alignment of protein sequences

Analysis of  a Protein Sequence: The Server allows the user to plot amino acid properties along protein primary structure (e.g. hydrophilicity/flexibility plot). One can select upto four properties out of 36 properties available with server, at a time to plot in a single window or in multiple windows.  User can select appropriate i) length of window used for averaging; ii) moment method to be applied before averaging; and iii) method used for averaging (Mean over window; Hat over window; Median; Data-sieve etc.)  It provides following optionson a single protein sequence.
 

• Computation of the physical properties of amino acids
• Presentation of the properties along the primary structure of a protein by 2-D graph
• Presentation of the amino acid properties along the primary structure as a table
• Highlight a residue or group of residues in the sequence that exhibits a specific function (e.g. hydrophobic residues, polar residues, and small residues)

Analysis of Multiple sequence alignment of proteins: The server allows to plot  amino acid properties of protein sequences along  sequence alignment. It create a sepreate graph corresponding to each sequence in alignment and present all the user selected properties in this graph. It provides the following options:
 

• Compute and present the overall property of each position in the alignment
• Highlight the conserved residues in alignment
• Highlight a residue in the alignment that exhibits a specific function
• Compute a position specific score matrix
• Similarity among the sequences present in the alignment.