4LVC

Crystal structure of S-adenosyl-L-homocysteine hydrolase from Bradyrhizobium elkanii in complex with adenosine

Summary for 4LVC

• Entry DOI: 10.2210/pdb4lvc/pdb
• Related: 1B3R 1LI4 3N58 3OND 3ONE 3ONF
• Descriptor: S-adenosyl-L-homocysteine hydrolase (SAHase), ADENOSINE, AMMONIUM ION, ... (7 entities in total)
• Functional Keywords: cellular methylation, sah hydrolysis, nad+ cofactor, atmospheric nitrogen fixation, rhizobium-legume symbiosis, hydrolase, nad+ cofactor complex
• Biological source: Bradyrhizobium elkanii
• Total number of polymer chains: 4
• Total formula weight: 216017.03

Authors

Manszewski, T.,Singh, K.,Imiolczyk, B.,Jaskolski, M. (deposition date: 2013-07-26, release date: 2014-07-30, Last modification date: 2023-09-20)

Primary citation

Manszewski, T.,Singh, K.,Imiolczyk, B.,Jaskolski, M.
An enzyme captured in two conformational states: crystal structure of S-adenosyl-L-homocysteine hydrolase from Bradyrhizobium elkanii.
Acta Crystallogr.,Sect.D, 71:2422-2432, 2015

PubMed Abstract: S-Adenosyl-L-homocysteine hydrolase (SAHase) is involved in the enzymatic regulation of S-adenosyl-L-methionine (SAM)-dependent methylation reactions. After methyl-group transfer from SAM, S-adenosyl-L-homocysteine (SAH) is formed as a byproduct, which in turn is hydrolyzed to adenosine (Ado) and homocysteine (Hcy) by SAHase. The crystal structure of BeSAHase, an SAHase from Bradyrhizobium elkanii, which is a nitrogen-fixing bacterial symbiont of legume plants, was determined at 1.7 Å resolution, showing the domain organization (substrate-binding domain, NAD(+) cofactor-binding domain and dimerization domain) of the subunits. The protein crystallized in its biologically relevant tetrameric form, with three subunits in a closed conformation enforced by complex formation with the Ado product of the enzymatic reaction. The fourth subunit is ligand-free and has an open conformation. The BeSAHase structure therefore provides a unique snapshot of the domain movement of the enzyme induced by the binding of its natural ligands.

PubMed: 26627650
DOI: 10.1107/S1399004715018659

Experimental method

X-RAY DIFFRACTION (1.74 Å)