Fig. 1

Layout of the web-application. The figure shows the layout of the application. a Input window. When “use example data” is clicked (highlighted by a red square) an example sequence and an example codon usage table appears in both Start-boxes. The example input sequence was created as a random sequence with a sequence generator. The example codon table was copied from the codon database from Escherichia coli O157:H7 EDL933. b When afterwards the “Start processing” button is clicked (red square) the software highlights all rare codons within the sequence and usage frequencies of the selected host organism are displayed under “usage data”. The sequence can now be optimized