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Figure 1.
Figure 1. The structure of truncated Schistosoma mansoni TGR in
ribbon representation, produced with CCP4MG.[23] Panel A:
Overall structural organization of the biological unit of the
enzyme: the W-shaped SmTGR dimer. One monomer is in blue and the
other monomer is colored according to the division in domains
from N- to C- terminus: Grx domain in light blue (1-107); FAD
binding domain in gold (108-257 and 391-461); NADPH binding
domain in green (258-358 and 364-390); the interface domain in
magenta (462-493). The linker regions between Grx and TR
(103-107) domains in magenta and the insertion (359-363)
peculiar to SmTGRs in red lie at the top and at the bottom,
respectively. Panel B: as in A, the view is from the top,
looking down the twofold dimerization axis (in black for
clarity). Panel C: The FAD binding site. View of the 2Fo-Fc
electron density map around the FAD cofactor contoured at 1.0
 .
The backbone of SmTGR around the active site is in ribbon, the
residues (K162 and Y296) that stabilize the position of the
flavine ring, together with the catalytic disulphide
(C154-C159), packing the isoalloxazine ring of the FAD, are
shown in sticks. Residues from the symmetrical monomer B, which
are implicated in the catalytic active site (H571B and E576B)
are also shown. Distances of the H-bond network range from 2.7
to 3.4 Å.
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