Figure 2.
Fig. 2. (a) Superposition of liganded (red) on the
unliganded (cyan) forms of L20/R63A. As representative examples,
the alternative positions of Ser-44 are labeled. On the lower
left and right are simulated-annealing omit maps (contoured at
1.1 ) with backbone
representations of the helix extended in both directions. (b)
Detailed sketch showing the structures of the liganded (Upper)
and the unliganded (Lower) forms. The "inserted" residues
(Asn-40-Ile-50) are colored orange, and the "parent" residues
(Asn-51-Ile-61, renumbered because of the 11-residue insert) are
colored blue. The vertical bars connecting the two structures
show the location of helix B in WT. In the presence of the
guanidinium ion (Upper), the inserted helix (in orange) extends
at its N terminus. In the absence of the ion (Lower), the
inserted sequence occupies the position of helix B and the
parent sequence extends the helix at its C terminus.
) with backbone
representations of the helix extended in both directions. (b)
Detailed sketch showing the structures of the liganded (Upper)
and the unliganded (Lower) forms. The "inserted" residues
(Asn-40-Ile-50) are colored orange, and the "parent" residues
(Asn-51-Ile-61, renumbered because of the 11-residue insert) are
colored blue. The vertical bars connecting the two structures
show the location of helix B in WT. In the presence of the
guanidinium ion (Upper), the inserted helix (in orange) extends
at its N terminus. In the absence of the ion (Lower), the
inserted sequence occupies the position of helix B and the
parent sequence extends the helix at its C terminus.