1ZNN

Structure of the synthase subunit of PLP synthase

Summary for 1ZNN

• Entry DOI: 10.2210/pdb1znn/pdb
• Descriptor: PLP SYNTHASE, SULFATE ION, (4R)-2-METHYLPENTANE-2,4-DIOL, ... (4 entities in total)
• Functional Keywords: tim barrel, biosynthetic protein
• Biological source: Geobacillus stearothermophilus
• Total number of polymer chains: 6
• Total formula weight: 212012.93

Authors

Zhu, J.,Burgner, J.W.,Harms, E.,Belitsky, B.R.,Smith, J.L. (deposition date: 2005-05-11, release date: 2005-05-24, Last modification date: 2024-02-14)

Primary citation

Zhu, J.,Burgner, J.W.,Harms, E.,Belitsky, B.R.,Smith, J.L.
A New Arrangement of (beta/alpha)8 Barrels in the Synthase Subunit of PLP Synthase.
J.Biol.Chem., 280:27914-27923, 2005

PubMed Abstract: Pyridoxal 5'-phosphate (PLP, vitamin B6), a cofactor in many enzymatic reactions, has two distinct biosynthetic routes, which do not coexist in any organism. Two proteins, known as PdxS and PdxT, together form a PLP synthase in plants, fungi, archaea, and some eubacteria. PLP synthase is a heteromeric glutamine amidotransferase in which PdxT produces ammonia from glutamine and PdxS combines ammonia with five- and three-carbon phosphosugars to form PLP. In the 2.2-A crystal structure, PdxS is a cylindrical dodecamer of subunits having the classic (beta/alpha)8 barrel fold. PdxS subunits form two hexameric rings with the active sites positioned on the inside. The hexamer and dodecamer forms coexist in solution. A novel phosphate-binding site is suggested by bound sulfate. The sulfate and another bound molecule, methyl pentanediol, were used to model the substrate ribulose 5-phosphate, and to propose catalytic roles for residues in the active site. The distribution of conserved surfaces in the PdxS dodecamer was used to predict a docking site for the glutaminase partner, PdxT.

PubMed: 15911615
DOI: 10.1074/jbc.M503642200

Experimental method

X-RAY DIFFRACTION (2.2 Å)