Biomolecular Modelling and Design Group, Bioinformatics Institute, 30 Biopolis Street, #07-01 Matrix, Singapore 138671. anita@bii.a-star.edu.sg|Biomolecular Modelling and Design Group, Bioinformatics Institute, 30 Biopolis Street, #07-01 Matrix, Singapore 138671. anita@bii.a-star.edu.sg