Center for biological sequence analysis, CBS, Kemitorvet 208, Technical University of Denmark, DK-2800 Lyngby, Denmark. lunde@cbs.dtu.dk|Center for biological sequence analysis, CBS, Kemitorvet 208, Technical University of Denmark, DK-2800 Lyngby, Denmark. lunde@cbs.dtu.dk|Center for biological sequence analysis, CBS, Kemitorvet 208, Technical University of Denmark, DK-2800 Lyngby, Denmark. lunde@cbs.dtu.dk|Center for biological sequence analysis, CBS, Kemitorvet 208, Technical University of Denmark, DK-2800 Lyngby, Denmark. lunde@cbs.dtu.dk|Center for biological sequence analysis, CBS, Kemitorvet 208, Technical University of Denmark, DK-2800 Lyngby, Denmark. lunde@cbs.dtu.dk