Search

Ten years after the idea of hydrophobic cluster analysis (HCA) was conceived and first pub lished, theoretical and practical experience has shown this unconventional method of protein sequence anal ysis to be particularly efficient and sensitive, especially with families of sequences sharing low levels of se quence identity. This extreme sensitivity has made it possible to predict the functions of genes whose se quence similarities are hardly if at all detectable by current one-dimensional (1D) methods alone, and of fers a new way to explore the enormous amount of data generated by genome sequencing. HCA also pro vides original tools to understand fundamental fea tures of protein stability and folding. Since the last review of HCA published in 1990 [1], significant im provements have been made and several new facets have been addressed. Here we wish to update and summarize this information.

Motivation: When routinely analysing protein sequences, detailed analysis of database search results made with BLAST and FASTA becomes exceedingly time consuming and tedious work, as the resultant file may contain a list of hundreds of potential homologies. The interpretation of these results is usually carried out with a text editor which is not a convenient tool for this analysis. In addition, the format of data within BLAST and FASTA output jiles makes them diflcult to read. Results: To facilitate and accelerate this analysis, we present, for the first time, two easy-to-use programs designed for interactive analysis of full BLAST and FASTA output files containing protein sequence alignments. The programs, Visual BLAST and Visual FASTA, run under Microsoft Windows 95 or NT systems They are based on the same intuitive graphical user interjiace (GUI) with extensive viewing, searching, editing, printing and multithreading capabilities. These programs improve the browsing of BLAST/FASTA results by offering a more convenient presentation of these results. They also implement on a computer several analytical tools which automate a manual methodology used for detailed analysis of BLAST and FASTA outputs These tools include a painvise sequence alignment viewer, a Hydrophobic Cluster Analysis plot alignment viewer and a tool displaying a graphical map of all database sequences aligned with the query sequence.In addition, Visual Blast includes tools for multiple sequence alignment analysis (with an amino acid patterns search engine), and Visual FASTA provides a GUI to the FASTA program. Availability: The programs are freely available on the Web (http://www.lmcp.jussieu.fr/{small tilde}durand). Contact: E-mail: durand@lmcp.jussieu.fr