Figure 1.

Number of protein structures and membrane protein structures deposited annually in the Protein Data Bank (PDB). (a) The total number of structures deposited in the PDB per year. The data are taken from the PDB website [17], which was last updated on 13 December 2005; the PDB currently holds 31,248 protein structures in total. (b) The number of unique membrane protein structures solved for the years indicated. The data are taken from [18], which was last updated on 11 December 2005.