PROFILEGRAPH: an interactive graphical tool for protein sequence analysis.

The computer program PROFILEGRAPH, a graphical interactive tool for the analysis of amino acid sequences, is described. The main task of the program is to integrate a variety of sliding-window methods into a single user-friendly shell. The program allows the user to combine any amino acid specific parameter with a selection of several possible types of analysis and to plot the resulting graph in one of several windows on the screen. It is also possible to calculate the moment of the amino acid specific parameter for a given secondary structure and to display both the absolute moment value and the moment angle relative to a reference residue. Also included are several utilities that facilitate visual analysis of protein primary structures like, for example, helical-wheel diagrams. It is possible to adapt the majority of published sliding-window analysis procedures for use with PROFILEGRAPH.