PDB Statistics: Number of Unique Protein Sequences within Released PDB Structures (Annual) at Identity 50%
This chart shows the total number of unique protein sequence clusters in PDB structures released within each year. Unique sequence clusters are defined using the sequence identity (SI). A value of 95% SI is used by default, since for practical purposes this identifies proteins with few differences, and thus can be considered to be the same sequence. The chart can also be redrawn with a more stringent 100% SI criterion, or with lower SI values that identify unique protein families (70% SI) or unique protein folds (30% SI).
The annual numbers of protein sequences may be displayed by specific levels of SI, either separately in different charts or simultaneously in the same chart.
Note: The number of unique sequences in the statistics table is linked to the sequence cluster search result page. There is a default precision threshold in calculating the numbers for performance balance. So the statistics count may have a slight discrepancy compared to the actual non-redundant group search result when the result count approaches or goes above 10,000. The group search result page provides an accurate count. The statistics page provides the trend.