Publications by authors named "Shinji Hourai"

In the nuclear receptor of vitamin D (VDR) histidine 305 participates to the anchoring of the ligand. The VDR H305Q mutation was identified in a patient who exhibited the hereditary vitamin D-resistant rickets (HVDRR). We report the crystal structure of human VDR H305Q-ligand binding domain bound to 1alpha,25(OH)2D3 solved at 1.

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Vitamin D nuclear receptor (VDR), a ligand-dependent transcriptional regulator, is an important target for multiple clinical applications, such as osteoporosis and cancer. Since exacerbated increase of calcium serum level is currently associated with VDR ligands action, superagonists with low calcium serum levels have been developed. Based on the crystal structures of human VDR (hVDR) bound to 1alpha,25-dihydroxyvitamin D(3) and superagonists-notably, KH1060-we designed a superagonist ligand.

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The crystal structures of vitamin D nuclear receptor (VDR) have revealed that all compounds are anchored by the same residues to the ligand binding pocket (LBP). Based on this observation, a synthetic analog with a locked side chain (21-nor-calcitriol-20(22),23-diyne) has been synthesized in order to gain in entropy energy with a predefined active side chain conformation. The crystal structure of VDR LBD bound to this locked side chain analogue while confirming the docking provides a structural basis for the activity of this compound.

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The crystal structure of the vitamin D receptor (VDR) in complex with 1 alpha,25(OH)2D3 revealed the presence of several water molecules near the A-ring linking the ligand C-2 position to the protein surface. Here, we report the crystal structures of the human VDR ligand binding domain bound to selected C-2 alpha substituted analogues, namely, methyl, propyl, propoxy, hydroxypropyl, and hydroxypropoxy. These specific replacements do not modify the structure of the protein or the ligand, but with the exception of the methyl substituent, all analogues affect the presence and/or the location of the above water molecules.

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Nitrile hydratase (NHase) converts nitriles to the corresponding amides and is recognized as having important industrial applications. Purification, cloning, crystallization and initial crystallographic studies of the NHase from Bacillus smithii SC-J05-1 (Bs NHase) were conducted to analyze the activity, specificity and thermal stability of this hydrolytic enzyme. Bs NHase was purified to homogeneity from microbial cells of B.

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There is a rapid global rise in obesity, and the link between obesity and diabetes remains somewhat obscure. We identified an adipocytokine, designated as visceral adipose tissue-derived serpin (vaspin), which is a member of serine protease inhibitor family. Vaspin cDNA was isolated by from visceral white adipose tissues (WATs) of Otsuka Long-Evans Tokushima fatty (OLETF) rat, an animal model of abdominal obesity with type 2 diabetes.

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The crystal structure of the nitrile hydratase (NHase) from Bacillus smithii SC-J05-1 was determined. Our analysis of the structure shows that some residues that seem to be responsible for substrate recognition are different from those of other NHases. In particular, the Phe52 in the beta subunit of NHase from B.

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A series of tricyclic indole-2-carboxylic acid derivatives were synthesized and evaluated by the radioligand binding assay and the anticonvulsant effects in the mouse NMDA-induced seizure model. Among them, derivatives of 3S-(-)-4 such as 3a, 3f, and 3g which had certain zwitterionic anilides showed high affinity to the NMDA-glycine binding site. The absolute configuration of 3S-(-)-4 was confirmed by X-ray crystallographic analysis.

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