1DIH

THREE-DIMENSIONAL STRUCTURE OF E. COLI DIHYDRODIPICOLINATE REDUCTASE

Summary for 1DIH

• Entry DOI: 10.2210/pdb1dih/pdb
• Descriptor: DIHYDRODIPICOLINATE REDUCTASE, NADPH DIHYDRO-NICOTINAMIDE-ADENINE-DINUCLEOTIDE PHOSPHATE (3 entities in total)
• Functional Keywords: oxidoreductase
• Biological source: Escherichia coli
• Total number of polymer chains: 1
• Total formula weight: 29539.05

Authors

Scapin, G.,Blanchard, J.S.,Sacchettini, J.C. (deposition date: 1994-09-14, release date: 1995-09-15, Last modification date: 2024-02-07)

Primary citation

Scapin, G.,Blanchard, J.S.,Sacchettini, J.C.
Three-dimensional structure of Escherichia coli dihydrodipicolinate reductase.
Biochemistry, 34:3502-3512, 1995

PubMed Abstract: Dihydrodipicolinate reductase is an enzyme found in bacteria and higher plants involved in the biosynthesis of diaminopimelic acid and lysine. Because these pathways are unique to bacteria and plants, they may represent attractive targets for new antimicrobial or herbicidal compounds. The three-dimensional structure of Escherichia coli dihydrodipicolinate reductase, complexed with NADPH, has been determined and refined to a crystallographic R-factor of 18.6% with diffraction data to 2.2 A resolution. The refined model contains the complete protein chain, the cofactor NADPH, and 55 water molecules. The enzyme is composed of two domains. The dinucleotide binding domain has a central seven-stranded parallel beta-sheet surrounded by four alpha-helices, with the cofactor binding site located at the carboxy-terminal edge of the sheet. The second domain contains four beta-strands and two alpha-helices that form an open mixed beta-sandwich. A possible binding site for dihydrodipicolinate has been identified in this second domain, about 12 A away from the dinucleotide binding site. This would imply that the protein must undergo some conformational change in order to perform catalysis. In the crystal, the native enzyme is a homotetramer generated by a 222 crystallographic axis. Implications of the tetrameric structure for the enzyme function are presented. Dihydrodipicolinate reductase uses both NADH and NADPH as cofactors, and analysis of its cofactor binding site allows for a molecular understanding of the enzyme's dual specificity.

PubMed: 7893645
DOI: 10.1021/bi00011a003

Experimental method

X-RAY DIFFRACTION (2.2 Å)