Table 1

Class membership of 212 pseudoknots from PseudoBase. The sequences were determined by comparative sequence analysis and/or by experimental techniques. The largest class of pseudoknots is simple recursive or even canonical simple recursive.
simple recursive pseudoknots
csr-PK
 1-nt bulge
 Rule 2 violated
 isolated basepair
 G-A basepair
 total
135
 11
 6
 17
 3
 172
complex pseudoknots
internal loop
 triple helix
 four helices
 kissing hairpins
 large bulge
 total
23
 12
 1
 3
 1
 40

Reeder and Giegerich BMC Bioinformatics 2004 5:104   doi:10.1186/1471-2105-5-104