|
Figure 3.
Fig. 3. Ser53 and Ser56 and the insertion of RCL: a model.
A: The ‘shutter region’ in the native form (in dark blue,
template α1-antitrypsin [27]). A ring of hydrogen bonds links
the side chain of Ser56, His334 and Asn186. B: After
preinsertion of the RCL (in green), His334 must rotate and
interact with the backbone C=O of Asn186. During the
preinsertion of the RCL, Val188 slides between Ser53 and Ser56 (
Fig. 4A), so Ser56 must also rotate. Consequently, Asn186 has to
rotate to maintain its interaction with Ser56 (antithrombin
structure used as a template [26]). C: Asn186 continues to slide
between residues 56 and 60 ( Fig. 4A). Its side chain rotates to
a similar position as seen in the native form. Ser351 takes the
place of Asn186 and the β-strand s3A translocates from its
preinserted position to its relaxed position (in orange;
structure of neuroserpin). The loss of the hydrogen bond between
Asn186 and His334 is compensated for by the formation of a
hydrogen bond with the OH side chain of Ser351. Prepared with
Setor [31].
|
