Fig. 3.

Alterations in hydrogen bonding of HSD10 by substitution of glutamine for glutamate 249. A comparison of C-terminal sequences of HSD10 orthologs (A) showed a conserved glutamate (*) before the last β-strand (βG). Comparison of 3-dimensional structure of C-terminals in chain D (Upper) and A (Lower) of HSD10 (B) with that of HSD10E249Q (C). The predicted hydrogen bond was displayed as a green dash line whereas oxygen in red, nitrogen in blue and sulfur in yellow. Hydrogen bonds in the subunit interface that will be broken by the E249Q mutation and other H-bonds formed by the carboxyl group of glutamate 249 side chain were indicated by arrow and small arrow, respectively.