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Circular permutation (CP) of protein is an evolutionary event resulting in the fact that structural homologs may have different locations of termini. It can be visualized as if the original termini of a protein were linked and new ones created elsewhere. Since circular permutants usually retain native structures and functions with sometimes increased stabilities, activities or functional diversities, CP has been applied as a protein engineering technique in many fields. Considering that not every position in a protein structure can be used to generate viable CP and the high cost for creating CP by molecular cloning, CP site predictors, which help avoid unnecessary trials-and-errors, will be beneficial for the application of CP. Here we present CPred, the first practical method for predicting viable CP sites.

Lo WC, Wang LF, Liu YY, Dai T, Hwang JK, Lyu PC: CPred: a web server for predicting viable circular permutations in proteins.
Nucleic Acids Research
2012, doi:10.1093/nar/gks529. [Abstract] [PDF]

Lo WC, Lee CC, Lee CY, Lyu PC: CPDB: a database of circular permutation in proteins.
Nucleic Acids Research 2009, 37:D328-332. [Abstract] [PDF]

Lo WC, Lyu PC: CPSARST: an efficient circular permutation search tool applied to the detection of novel protein structural relationships.
Genome Biology
2008, 9:R11. [Abstract] [PDF]

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Yu-Hung Chen, Li-Fen Wang, Jenn-Kang Hwang, and Wei-Cheng Lo
Maintained at Institute of Bioinformatics and Systems Biology, NCTU, Taiwan