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Figure 4
Structures of the enzyme variants analyzed in this work. (a) Superposition of the Cα traces of wild-type StEH1 (wheat) and the variants R-C1 (lime green), R-C1B1 (violet), R-C1B1D33 (aquamarine) and R-C1B1D33E6 (orange). (b) Overlay of active-site residues, including those that differ between the different enzyme variants. The catalytic residues are Asp105 (nucleophile), His300 (general base), Asp265 (charge relay) and Tyr154 and Tyr235 (acids) (see Fig. 1[link] for the full reaction mechanism). Glu35 and His104 are auxiliary catalytic residues. The hydrolytic water (wat) is also shown. A glycerol molecule (gol) bound in the active site of R-C1 has been included to show the substrate-binding pocket. The residue replacements are given in Table 2[link]. The modelled side-chain conformations of Lys141 should be considered arbitrary owing to a lack of clear electron density beyond Cγ. This figure was constructed from the atomic coordinates in PDB entries 2cjp (wild type; Mowbray et al., 2006BB26), 4uhb (R-C1; Janfalk Carlsson et al., 2016BB15), 4ufn (R-C1B1; Bauer et al., 2016BB5), 4ufp (R-C1B1D33; Janfalk Carlsson et al., 2016BB15) and 4ufo (R-­C1B1D33E6; Janfalk Carlsson et al., 2016BB15) using PyMOL v.1.8.7.

Volume 5| Part 3| May 2018| Pages 269-282
ISSN: 2052-2525