1ulz
From Proteopedia
Crystal structure of the biotin carboxylase subunit of pyruvate carboxylase
Overview
Pyruvate carboxylase (PC) is distributed in many eukaryotes as well as in some prokaryotes. PC catalyzes the ATP-dependent carboxylation of pyruvate to form oxalacetate. PC has three functional domains, one of which is a biotin carboxylase (BC) domain. The BC subunit of PC from Aquifex aeolicus (PC-beta) was crystallized in an orthorhombic form with space group P2(1)2(1)2, unit-cell parameters a = 92.4, b = 122.1, c = 59.0 A and one molecule in the asymmetric unit. Diffraction data were collected at 100 K on BL24XU at SPring-8. The crystal structure was determined by the molecular-replacement method and refined against 20.0-2.2 A resolution data, giving an R factor of 0.199 and a free R factor of 0.236. The crystal structure revealed that PC-beta forms a dimeric quaternary structure consisting of two molecules related by crystallographic twofold symmetry. The overall structure of PC-beta is similar to other biotin-dependent carboxylases, such as acetyl-CoA carboxylase (ACC). Although some parts of domain B were disordered in ACC, the corresponding parts of PC-beta were clearly determined in the crystal structure. From comparison between the active-site structure of ACC with ATP bound and a virtual model of PC-beta with ATP bound, it was shown that the backbone torsion angles of Glu203 in PC-beta change and some of water molecules in the active site of PC-beta are excluded upon ATP binding.
About this Structure
1ULZ is a Single protein structure of sequence from Aquifex aeolicus. Full crystallographic information is available from OCA.
Reference
Structure of the biotin carboxylase subunit of pyruvate carboxylase from Aquifex aeolicus at 2.2 A resolution., Kondo S, Nakajima Y, Sugio S, Yong-Biao J, Sueda S, Kondo H, Acta Crystallogr D Biol Crystallogr. 2004 Mar;60(Pt 3):486-92. Epub 2004, Feb 25. PMID:14993673 Page seeded by OCA on Sat May 3 11:24:39 2008
