''IDH1'' is most highly expressed in the mammalian liver, with moderate expression in other tissues [1]. A C-terminal peroxisome targeting signal 1 sequence allows for its peroxisomal localization [2]. The IDH1 protein is comprised of a large domain (residues 1-103 and 286-414, NM_005896.2/NP_005887.2), a small domain (residues 104-136 and 186-285, NM_005896.2/NP_005887.2) and a clasp domain (residues 137-185, NM_005896.2/NP_005887.2) [3]. The clasp domain holds together two IDH1 subunits and the enzyme active site is formed in a cleft created by the large and small domains of each subunit. Each active site can bind NADP+ and a metal ion in addition to the isocitrate substrate. | ''IDH1'' is most highly expressed in the mammalian liver, with moderate expression in other tissues [1]. A C-terminal peroxisome targeting signal 1 sequence allows for its peroxisomal localization [2]. The IDH1 protein is comprised of a large domain (residues 1-103 and 286-414, NM_005896.2/NP_005887.2), a small domain (residues 104-136 and 186-285, NM_005896.2/NP_005887.2) and a clasp domain (residues 137-185, NM_005896.2/NP_005887.2) [3]. The clasp domain holds together two IDH1 subunits and the enzyme active site is formed in a cleft created by the large and small domains of each subunit. Each active site can bind NADP+ and a metal ion in addition to the isocitrate substrate. |