Bioinformatics and Computational Biochemistry Group, European Media Laboratory GmbH, Schloss-Wolfsbrunnenweg 33, D-69118, Heidelberg, Germany. Ursula.Rost@eml.villa-bosch.de|Bioinformatics and Computational Biochemistry Group, European Media Laboratory GmbH, Schloss-Wolfsbrunnenweg 33, D-69118, Heidelberg, Germany. Ursula.Rost@eml.villa-bosch.de