Distribution of multi-interface domains at different SCOP classification levels.

•number of clusters under the given SCOP classification level;°number of clusters that have multi-interface proteins under the given SCOP classification level;†number of protein chains that have multi-interfaces;‡data is not available in SCOP;*the total number of domains is 97,178 in SCOP version 1.73, but the total number of domains listed above is slightly smaller since there are still four classes with very few number of domains are not shown here.SCOP version 1.73 instead of 1.75 is used in this study because the PDBeFold [34] is based on SCOP version 1.73, which is used to search SCOP to get similar domains for a given protein.