Figure 3.
Fig. 3. Asymmetric conformation of the putative catalytic
arginine residue in the G2 element. (a) In the structure of the
FlhF/GMPPNP, both Arg-216 residues of the homodimer are well
defined in an unbiased F[o] – F[c] difference density map (2.0
;
calculated without the arginines; green grid). Their asymmetric
arrangement is as observed for the corresponding arginines in b
for the SRP/SR heterodimer with bound GMPPCP from T. aquaticus
(21). (c) Sequence alignment of G2 elements in SRP GTPases. The
sequence is annotated as in Fig. 1c. Note: The crystal of the
FlhF/GMPPNP complex contains eight monomers in the AU that form
four noncrystallographic dimers. The asymmetry of Arg-216 is
observed in all of them.
;
calculated without the arginines; green grid). Their asymmetric
arrangement is as observed for the corresponding arginines in b
for the SRP/SR heterodimer with bound GMPPCP from T. aquaticus
(21). (c) Sequence alignment of G2 elements in SRP GTPases. The
sequence is annotated as in Fig. 1c. Note: The crystal of the
FlhF/GMPPNP complex contains eight monomers in the AU that form
four noncrystallographic dimers. The asymmetry of Arg-216 is
observed in all of them.