Center for Biomembrane Research, Stockholm Bioinformatics Center, Dept of Biochemistry and Biophysics, Stockholm University, SE-106 91 Stockholm, Sweden.|Center for Biomembrane Research, Stockholm Bioinformatics Center, Dept of Biochemistry and Biophysics, Stockholm University, SE-106 91 Stockholm, Sweden.|Center for Biomembrane Research, Stockholm Bioinformatics Center, Dept of Biochemistry and Biophysics, Stockholm University, SE-106 91 Stockholm, Sweden.