Systematic Analysis of Compositional Order of Proteins Reveals New Characteristics of Biological Functions and a Universal Correlate of Macroevolution
Figure 1
Analysis of Swiss-Prot human proteome.
Analysis of Swiss-Prot human proteome (n = 20248) containing 5511 CO proteins. A) Histogram of the most frequent intervals, MFI, demonstrates the significant periodic structures originating in ‘runs’ of homo-peptides (MFI = 1) and zinc-fingers (MFI = 28). B) The frequency of intervals of all FTs in all proteins (black circles). The outstanding symbols are mostly due to Zinc-finger proteins which form repetitive sections of 28 amino-acids. Multiplicities at intervals 56, 84 amino-acid are also evident due to mutation acting on these sections. The superimposed red dots display the data in a rank-ordered manner (i.e. the x-axis takes on the role of rank rather than value of interval). C) The number of periodic proteins as defined by the number of FT occurrences at MFI. The bars indicate the fraction of CO proteins with exactly 2–20 (x-axis) occurrences at MFI. 20% of CO proteins are non-periodic (NP). Circles represent the cumulative fraction of proteins with number of repetitions at MFI above the value indicated by the x-axis. Thus, for a minimum of 4 repeats at MFI (i.e., x = 3), there are above 50% CO proteins with periodic structures.