1. Volume 6, Issue 5, Pages 1207-1218 (November 2000)
The β-Slip 
Therese Eneqvist, Karin Andersson, Anders Olofsson, Erik Lundgren, A.Elisabeth Sauer-Eriksson 
Molecular Cell 
Volume 6, Issue 5, Pages (November 2000)
DOI: /S (00)

2. Figure 1 Western Blot of Dissolved TTRG53S/E54D/L55S Crystals
(A) Immunoreactivity toward polyclonal anti-human TTR.
(B) Reactivity toward MAB(39–44).
(C) Reactivity toward MAB(56–61).
The crystals were carefully washed in mother liquor before they were dissolved in a solution containing 50 mM Tris (pH 7.5) and 20% glycerol and separated on a 16% polyacrylamide gel. Crystals and protein solution were taken from the same drop; purified TTRG53S/E54D/L55S and wild-type TTR were included as controls. Lanes: 1, purified TTRG53S/E54D/L55S; 2, protein from crystallization drop; 3, protein from dissolved crystals; 4, wild-type TTR.
Molecular Cell 2000 6, DOI: ( /S (00) )

3. Figure 2 The TTRG53S/E54D/L55S Structure
(A) Schematic representation of the tetramer colored according to the temperature factor distribution from blue (low values) to red (high values).
(B) Superpositioning of monomers A (blue), B (red), C (magenta), and D (green) on monomer A of native transthyretin (PDB code 1f41) shown in dashed, black lines.
Molecular Cell 2000 6, DOI: ( /S (00) )

4. Figure 3
The β-Slip
(A) Monomer A from native transthyretin. The leucines at positions 55 and 58 are colored red and presented as ball-and-stick. The position of the triple mutation G53S/E54D/L55S is shown in green, and the two amyloid-specific epitopes (39–44) and (56–61) are shown in magenta and blue, respectively.
(B) Monomer B from TTRG53S/E54D/L55S. A three-residue shift in the protein main chain places Leu-58 into the position normally occupied by Leu-55. The mutation site and former β strand D, residues 53 to 55, are now situated in the new, longer CD loop. Both amyloid-specific epitopes (39–44) and (56–61) are structurally altered.
(C) A 2Fo-Fc electron density omit map contoured at 1σ level over the finally refined coordinates showing the quality of the electron density at the β-slip area in monomer B. To reduce model bias, residues Thr-49–Glu-63 were excluded from all monomers and subjected to one round of simulated annealing refinement (CNS) prior to the map calculation.
(D) The same as in (C) but over monomer D.
Molecular Cell 2000 6, DOI: ( /S (00) )

5. Figure 4 The Potential Amyloid Packing Site
(A) The interaction between the β-slip region (blue) and the RBP-binding site (gray). The conformation of native TTR is shown in red.
(B) A 2Fo-Fc electron density map contoured at 1σ level of the PAPS in monomer B.
Molecular Cell 2000 6, DOI: ( /S (00) )

6. Figure 5 The Helical Crystal Packing Interactions
(A) Schematic representation of the crystal packing along the three-fold screw axis. Two identical helices, colored gray and blue, connected by the PAPSs form a double helix.
(B) Within the double helix, a second type of helix can be obtained, visualized in magenta.
(C) The β strands C from two symmetry-related molecules form incomplete protein–protein contacts within the second helix.
(D) A large proportion of the core strands are directed perpendicular to the three-fold screw axis.
Molecular Cell 2000 6, DOI: ( /S (00) )

7. Figure 6 Proposed Model for Transthyretin Amyloid Formation
Model for amyloid formation based on the β-slip, PAPS, and helical crystal packing observed in TTRG53S/E54D/L55S. Monomers that contain a β-slip are colored red, while monomers that can be either native or amyloidogenic folds are gray or blue.
Molecular Cell 2000 6, DOI: ( /S (00) )