Unique amino acid distribution and average protein length.

<p>A Cumulative distribution function of unique amino acid count occurrence in proteins. The analysis encompassed all archaeal, bacterial, eukaryotic and viral proteins that were combined into the experimental PTM <i>P</i>_<i>exp</i> subset [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0125663#pone.0125663.ref022" target="_blank">22</a>]. B A plot of number of proteins against total length of those proteins for each species in SwissProt for unique counts from 1-30 amino acids. Each data point is one of the 13,041 species analysed C An expanded plot of the data in the bottom left hand corner of Fig 1B for species with less than 500 proteins, showing sub-structure.