2FCV

SyrB2 with Fe(II), bromide, and alpha-ketoglutarate

Summary for 2FCV

• Entry DOI: 10.2210/pdb2fcv/pdb
• Related: 2FCT 2FCU
• Descriptor: syringomycin biosynthesis enzyme 2, FE (II) ION, BROMIDE ION, ... (6 entities in total)
• Functional Keywords: mononuclear iron, cupin, halogenase, biosynthetic protein
• Biological source: Pseudomonas syringae
• Total number of polymer chains: 2
• Total formula weight: 72585.13

Authors

Blasiak, L.C.,Drennan, C.L. (deposition date: 2005-12-12, release date: 2006-03-21, Last modification date: 2024-04-03)

Primary citation

Blasiak, L.C.,Vaillancourt, F.H.,Walsh, C.T.,Drennan, C.L.
Crystal structure of the non-haem iron halogenase SyrB2 in syringomycin biosynthesis.
Nature, 440:368-371, 2006

PubMed Abstract: Non-haem Fe(II)/alpha-ketoglutarate (alphaKG)-dependent enzymes harness the reducing power of alphaKG to catalyse oxidative reactions, usually the hydroxylation of unactivated carbons, and are involved in processes such as natural product biosynthesis, the mammalian hypoxic response, and DNA repair. These enzymes couple the decarboxylation of alphaKG with the formation of a high-energy ferryl-oxo intermediate that acts as a hydrogen-abstracting species. All previously structurally characterized mononuclear iron enzymes contain a 2-His, 1-carboxylate motif that coordinates the iron. The two histidines and one carboxylate, known as the 'facial triad', form one triangular side of an octahedral iron coordination geometry. A subclass of mononuclear iron enzymes has been shown to catalyse halogenation reactions, rather than the more typical hydroxylation reaction. SyrB2, a member of this subclass, is a non-haem Fe(II)/alphaKG-dependent halogenase that catalyses the chlorination of threonine in syringomycin E biosynthesis. Here we report the structure of SyrB2 with both a chloride ion and alphaKG coordinated to the iron ion at 1.6 A resolution. This structure reveals a previously unknown coordination of iron, in which the carboxylate ligand of the facial triad is replaced by a chloride ion.

PubMed: 16541079
DOI: 10.1038/nature04544

Experimental method

X-RAY DIFFRACTION (1.8 Å)