Stockholm Format

Stockholm format is a Multiple sequence alignment format used by Pfam and Rfam to disseminate protein and RNA sequence alignments . The alignment editors Ralee and Belvu support Stockholm format as do the probabilistic database search tools, Infernal and HMMER, and the phylogenetic analysis tool Xrate. A simple example of an Rfam alignment (UPSK RNA) with a pseudoknot in Stockholm format is shown below:

# STOCKHOLM 1.0 #=GF ID UPSK #=GF SE Predicted; Infernal #=GF SS Published; PMID 9223489 #=GF RN #=GF RM 9223489 #=GF RT The role of the pseudoknot at the 3' end of turnip yellow mosaic #=GF RT virus RNA in minus-strand synthesis by the viral RNA-dependent RNA #=GF RT polymerase. #=GF RA Deiman BA, Kortlever RM, Pleij CW; #=GF RL J Virol 1997;71:5990-5996. AF035635.1/619-641 UGAGUUCUCGAUCUCUAAAAUCG M24804.1/82-104 UGAGUUCUCUAUCUCUAAAAUCG J04373.1/6212-6234 UAAGUUCUCGAUCUUUAAAAUCG M24803.1/1-23 UAAGUUCUCGAUCUCUAAAAUCG #=GC SS_cons .AAA....<<<>>> //

Here is a slightly more complex example showing the Pfam CBS domain:

# STOCKHOLM 1.0 #=GF ID CBS #=GF AC PF00571 #=GF DE CBS domain #=GF AU Bateman A #=GF CC CBS domains are small intracellular modules mostly found #=GF CC in 2 or four copies within a protein. #=GF SQ 5 #=GS O31698/18-71 AC O31698 #=GS O83071/192-246 AC O83071 #=GS O83071/259-312 AC O83071 #=GS O31698/88-139 AC O31698 #=GS O31698/88-139 OS Bacillus subtilis O83071/192-246 MTCRAQLIAVPRASSLAEAIACAQKMRVSRVPVYERS #=GR O83071/192-246 SA 9998877564535242525515252536463774777 O83071/259-312 MQHVSAPVFVFECTRLAYVQHKLRAHSRAVAIVLDEY #=GR O83071/259-312 SS CCCCCHHHHHHHHHHHHHEEEEEEEEEEEEEEEEEEE O31698/18-71 MIEADKVAHVQVGNNLEHALLVLTKTGYTAIPVLDPS #=GR O31698/18-71 SS CCCHHHHHHHHHHHHHHHEEEEEEEEEEEEEEEEHHH O31698/88-139 EVMLTDIPRLHINDPIMKGFGMVINN..GFVCVENDE #=GR O31698/88-139 SS CCCCCCCHHHHHHHHHHHHEEEEEEEEEEEEEEEEEH #=GC SS_cons CCCCCHHHHHHHHHHHHHEEEEEEEEEEEEEEEEEEH O31699/88-139 EVMLTDIPRLHINDPIMKGFGMVINN..GFVCVENDE #=GR O31699/88-139 AS ________________*____________________ #=GR O31699/88-139 IN ____________1____________2______0____ //

A minimal well formed Stockholm files should contain the header which states the format and version identifier, currently '# STOCKHOLM 1.0'. Followed by the sequences and corresponding unique sequence names:

'' stands for "sequence name", typically in the form "name/start-end" or just "name". Finally, the "//" line indicates the end of the alignment. Sequence letters may include any characters except whitespace. Gaps may be indicated by "." or "-".