SPRITZ: help and references
The Server: description
Spritz is a web
server for the prediction of intrinsically disordered regions in
protein sequences. Our server predicts ordered/disordered residues
using two specialised binary classifiers both implemented with probabilistic
soft-margin support vector machines or C-SVM. The SVM-LD (LD: long disorder) classifier is trained on
a subset of non redundant sequences known to contain only long disordered
protein fragments (>=30 AA). The SVM-SD (SD: short disorder) classifier
is trained instead on a subset of non redundant sequences with only short
Your email address, the place where the prediction will be delivered.
An optional name for your query. We strongly suggest that you use one.
The order in which you send your queries
may not correspond to the order in which you receive the answers.
The sequence of amino acids:
You have two options:
False positive rate threshold
You can set the false positive rate threshold (FPR) used by Spritz to map the probabilistic output into the final predicted residue class (ordered/disordered). We suggest you to choose the FPR with the help of Table I (SVM-SD), Table II (SVM-LD) and Fig. I. Basically, the FPR can be chosen according to the fraction of disordered amino acids that you expect to be recovered (sensitivity) or the fraction of predicted disordered residues estimated to be correct (specificity).
Replies are sent by email and come as text, attached to the message. You might have to "view attachments inline" in your web browser to see these replies. If you submit multiple sequences through Spritz_Multi you will receive one separate email for each sequence. Here you have an example of prediction:
VELVEGDEGRMCVNTEWGAFGDSGELDEFLLEYDRLVDESSANPGQQLYEKLIGGKYMGE CCEECCCCCCEEEECCCCCCCCCCCCCCCCCCHHHHHCCCCCCCCHHHHHHHHCCCCCCC DDOOODDDOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOODDDDDOOOOOOOOOOOODDDD
The lines have the following meaning:
A.Vullo, O.Bortolami, G.Pollastri, S.Tosatto. "Spritz: a server for the prediction of intrinsically disordered regions in protein sequences using kernel machines". Nucleic Acids Research, 34:W164-W168, 2006.
"Porter: a new, accurate server for protein secondary structure prediction".
Bioinformatics, 21(8),1719-20, 2005.
Back to Spritz
Gianluca Pollastri's group
School of Computer Science and Informatics
University College Dublin
University of Padua