Crystal structure of procathepsin H.

<p>(A) Overall structure of procathepsin H. Left, the prodomain and the mature domain are colored in violet and cyan respectively. The mini-chain is colored in blue. The prodomain contains two conserved sequence motifs: ERFNIN motif (orange) and GNFD motif (green). The four disulfide bonds in the structure are highlighted in yellow.Right, the 2<i>F</i>_<i>o</i>-<i>F</i>_<i>c</i> electron density map (top) and <i>F</i>_<i>o</i>-<i>F</i>_<i>c</i> omit map (bottom) of the mini-chain are displayed as the grey mesh at a contour level of 1.2<i>σ</i> and 3<i>σ</i> respectively. (B) Superposition of procathepsin H (cyan) and procathepsin L (violet). (C) Superposition of human procathepsin H (cyan) and mature porcine cathepsin H (wheat). The mini-chain of human procathepsin H is shown in blue and that of mature porcine cathepsin H is shown in orange. (D) Hydrogen bonding interactions between the β strand from prodomain (violet) and β strand from right subdomain (cyan). Backbones of the residues involved are shown as sticks. The distances between atoms are indicated by dashes. (E) Interactions between hydrophobic residues from prodomain (violet) and the mature domain (cyan). Sidechains of the residues involved are shown as sticks. (F) Hydrogen bonding interactions between the C-terminal linker of prodomain (violet) and core enzyme (cyan). Backbones and sidechains of the residues involved are shown as sticks. The distances between atoms are indicated by dashes.