Literature summary for 2.4.2.12 extracted from

Takahashi, R.; Nakamura, S.; Nakazawa, T.; Minoura, K.; Yoshida, T.; Nishi, Y.; Kobayashi, Y.; Ohkubo, T.
Structure and reaction mechanism of human nicotinamide phosphoribosyltransferase (2010), J. Biochem., 147, 95-107.

Crystallization (Commentary)

Crystallization (Comment)	Organism
crystal structures of the enzyme in the free form and bound to nicotinamide and 5-phospho-alpha-D-ribose 1-diphosphate at the resolution of 2.0 A to 2.2 A are essentially identical to that of the complex with nicotinamide mononucleotide, except for some variations that can facilitate the substitution reaction by fixing the nucleophile and the leaving group for the requisite inversion of configuration at the C1-carbon of the ribose ring. In the active site near the C1-atom of the bound 5-phospho-alpha-D-ribose 1-diphosphate or nicotinamide mononucleotide, there is neither negatively charged group nor waterproof environment necessary to support the feasibility of a ribo-oxocarbocation intermediate inherent in the SN1 mechanism	Homo sapiens

Crystallization (Comment)

Organism

crystal structures of the enzyme in the free form and bound to nicotinamide and 5-phospho-alpha-D-ribose 1-diphosphate at the resolution of 2.0 A to 2.2 A are essentially identical to that of the complex with nicotinamide mononucleotide, except for some variations that can facilitate the substitution reaction by fixing the nucleophile and the leaving group for the requisite inversion of configuration at the C1-carbon of the ribose ring. In the active site near the C1-atom of the bound 5-phospho-alpha-D-ribose 1-diphosphate or nicotinamide mononucleotide, there is neither negatively charged group nor waterproof environment necessary to support the feasibility of a ribo-oxocarbocation intermediate inherent in the SN1 mechanism

Homo sapiens

Organism

Organism	UniProt	Comment	Textmining
Homo sapiens	P43490	-	-

Substrates and Products (Substrate)

Substrates	Comment Substrates	Organism	Products	Comment (Products)	Rev.	Reac.
nicotinamide + 5-phospho-alpha-D-ribose 1-diphosphate	reaction is reversible as dictated by the equilibrium constant K, [NMN][PPi]/([NM][PRPP]) of 0.14, which agrees well with the ratio of second-order rate constants for forward and backward reactions, K of0.16	Homo sapiens	nicotinamide D-ribonucleotide + diphosphate	-	r

Use of this online version of BRENDA is free under the CC BY 4.0 license. See terms of use for full details.

Release 2023.1 (January 2023)