Crystal structure of thermostable acetaldehyde dehydrogenase from the hyperthermophilic archaeon, Sulfolobus tokodaii
Shohei Mine, Makoto Nakabayashi and Kazuhiko Ishikawa [1]
Molecular Tour
Aldehyde dehydrogenase (ALDH) plays an important role in aldehyde detoxification. Acetaldehyde is also considered carcinogenic and toxic. Thermostable ALDH from the hyperthermophilic archaeon Sulfolobus tokodaii (ALDHSt), exhibits high activity toward acetaldehyde and has potential applications as a biosensor for acetaldehyde. This structural information provides clues regarding the mechanisms of substrate recognition and thermostability in ALDH.
is a dimer of dimers (A/B and C/D) with crystallographic 222 symmetry. . The cofactor-binding domain, catalytic domain and oligomerization domain are shown in green, cyan and magenta, respectively. NADP is shown as a yellow stick model.
. NADP and NADP-interacting residues are shown in ball-and-stick representation, water molecules are shown as red spheres. Hydrogen bonds are shown as dashed lines. (colored in deep pink). . An omit Fo - Fc electron-density map for ligands was observed between the side chains of Asn142 and Cys274. This space appeared to be the binding-site cleft for the substrate. Therefore, we propose the involvement of the amide group of the side chain of Asn142 in an oxyanion hole to stabilize the reaction intermediate, as suggested previously. Arg88 and Phe143 were also observed near this site, but were not conserved in ALDH.
. Remember to drag the structures with the mouse to rotate them. Arg, Glu and Asp residues involved in salt bridges are shown as ball-and-stick models with the interactions shown as dashed lines on the alpha-helix structures in the cofactor-binding domain of ALDHSt.
References
- ↑ Mine S, Nakabayashi M, Ishikawa K. Crystal structure of thermostable acetaldehyde dehydrogenase from the hyperthermophilic archaeon Sulfolobus tokodaii. Acta Crystallogr F Struct Biol Commun. 2023 Jun 1;79(Pt 6):159-165. PMID:37227376 doi:10.1107/S2053230X23004430
