Figure 4.
Figure 4 MalT-binding site. (A) The active dimer of MalY
illustrating the location of the MalT interaction patch. The C^
traces
of both monomers (white and green) are overlaid with a
transparent surface. The MalT interaction regions are emphasized
by a solid surface that was defined on the basis of the negative
repressor mutants (drawn in red). The PLP cofactor is shown in a
van der Waals representation. Note that the MalT-binding surface
and the active site entrance to the PLP cofactor are located on
opposite sides of the individual MalY monomers. (B) Spatial
structure of the MalT-binding patch, which is constructed from
the three segments I, II and III as described in the text. The C
atoms of segments I, II and III are coloured orange (residues
81–85), white (residues 179–191) and green (residues
212–222), respectively. For each segment, the most important
residue regarding MalT repression (Table II) is labelled. The
model is overlaid with a transparent surface that is colour
coded by atom type. (C) Overlay of the wild-type and A221V MalT
interaction segments I, II and III. The wild-type model and the
corresponding surface are in white, the A221V mutant in green.
Obviously, the mutation Ala221 to Val221 results in a concerted
structural reorientation of all three segments. The orientations
of (B) and (C) are identical.
traces
of both monomers (white and green) are overlaid with a
transparent surface. The MalT interaction regions are emphasized
by a solid surface that was defined on the basis of the negative
repressor mutants (drawn in red). The PLP cofactor is shown in a
van der Waals representation. Note that the MalT-binding surface
and the active site entrance to the PLP cofactor are located on
opposite sides of the individual MalY monomers. (B) Spatial
structure of the MalT-binding patch, which is constructed from
the three segments I, II and III as described in the text. The C
atoms of segments I, II and III are coloured orange (residues
81–85), white (residues 179–191) and green (residues
212–222), respectively. For each segment, the most important
residue regarding MalT repression (Table II) is labelled. The
model is overlaid with a transparent surface that is colour
coded by atom type. (C) Overlay of the wild-type and A221V MalT
interaction segments I, II and III. The wild-type model and the
corresponding surface are in white, the A221V mutant in green.
Obviously, the mutation Ala221 to Val221 results in a concerted
structural reorientation of all three segments. The orientations
of (B) and (C) are identical.