Insights into ligand binding and catalysis of a central step in NAD+ synthesis: structures of Methanobacterium thermoautotrophicum NMN adenylyltransferase complexes

J Biol Chem. 2001 Mar 9;276(10):7225-32. doi: 10.1074/jbc.M008810200. Epub 2000 Nov 3.

Abstract

Nicotinamide mononucleotide adenylyltransferase (NMNATase) catalyzes the linking of NMN(+) or NaMN(+) with ATP, which in all organisms is one of the common step in the synthesis of the ubiquitous coenzyme NAD(+), via both de novo and salvage biosynthetic pathways. The structure of Methanobacterium thermoautotrophicum NMNATase determined using multiwavelength anomalous dispersion phasing revealed a nucleotide-binding fold common to nucleotidyltransferase proteins. An NAD(+) molecule and a sulfate ion were bound in the active site allowing the identification of residues involved in product binding. In addition, the role of the conserved (16)HXGH(19) active site motif in catalysis was probed by mutagenic, enzymatic and crystallographic techniques, including the characterization of an NMN(+)/SO4(2-) complex of mutant H19A NMNATase.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Binding Sites
  • Catalysis
  • Catalytic Domain
  • Chromatography, Gel
  • Cloning, Molecular
  • Crystallography, X-Ray
  • Ligands
  • Methanobacterium / enzymology*
  • Models, Chemical
  • Models, Molecular
  • Molecular Sequence Data
  • Mutagenesis
  • Mutagenesis, Site-Directed
  • Mutation
  • NAD / biosynthesis*
  • Nicotinamide-Nucleotide Adenylyltransferase / chemistry*
  • Nicotinamide-Nucleotide Adenylyltransferase / genetics
  • Protein Binding
  • Protein Conformation
  • Protein Structure, Secondary
  • Sequence Homology, Amino Acid

Substances

  • Ligands
  • NAD
  • Nicotinamide-Nucleotide Adenylyltransferase

Associated data

  • PDB/1EJ2
  • PDB/1HYB