|
Figure 2.
The completed structure of the periplasmic adaptor. (A)
Structure of MexA including the MP domain. The 4 adaptor domains
are: α-hairpin (blue), lipoyl (green), β-barrel (yellow), and
MP β-roll (orange). Turns are gray except for 2 MP domain
helical turns (yellow) that include Gly residues (white Cα
atoms) on the concave surface effecting crystal contacts. The
enlarged inset gives a smoothed representation of the MP domain
topology, with elements numbered according to the adaptor family
sequence alignment (Fig. S1) and colored from blue to red.
Trp-309 is shown in gray. (B) The MP domain: conformational
variation, rotation, and crystal contacts. The MexA adaptor
barrel (yellow) and MP (orange) domain, shown in the unrotated
MP domain conformation, establish crystal contacts with a
neighboring copy (gray), with the MP domain in its rotated
conformation. Helical turns on the MP domain concave face are in
yellow, and Gly-281 and Trp-309 are shown as white Cα atoms and
gray side-chains, respectively (labeled in italics on the
rotated domain).
|
