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1pya
From Proteopedia
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| , resolution 2.5Å | |||||||
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| Activity: | Histidine decarboxylase, with EC number 4.1.1.22 | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
REFINED STRUCTURE OF THE PYRUVOYL-DEPENDENT HISTIDINE DECARBOXYLASE FROM LACTOBACILLUS 30A
Overview
The crystal structure of the pyruvoyl-dependent histidine decarboxylase from Lactobacillus 30a has been refined to an R-value of 0.15 (for the 5.0 to 2.5 A resolution shell) and 0.17 (for the 10.0 to 2.5 A resolution shell). A description of the overall structure is presented, focusing on secondary structure and subunit association. The enzyme is a hexamer of alpha beta subunits. Separate alpha and beta-chains arise from an autocatalytic cleavage reaction between two serine residues, which results in the pyruvoyl cofactor. The central core of the alpha beta subunit is a beta-sandwich which consists of two face-to-face three-stranded antiparallel beta-sheets, flanked by alpha-helices on each side. The beta-sandwich creates a stable fold that allows conformational strain to be introduced across an internal cleavage region between the alpha and beta chains and places the pyruvoyl cofactor in a position for efficient electron withdrawal from the substrate. Three alpha beta subunits are related by a molecular three-fold symmetry axis to form a trimer whose interfaces have complementary surfaces and extensive molecular interactions. Each of the interfaces contains an active site and a solvent channel that leads from the active site to the exterior of the molecule. The trimers are related by a crystallographic two-fold symmetry axis to form the hexamer with an overall dumbbell shape. The interface between trimers has few molecular interactions.
About this Structure
1PYA is a Protein complex structure of sequences from Lactobacillus sp.. Full crystallographic information is available from OCA.
Reference
Refined structure of the pyruvoyl-dependent histidine decarboxylase from Lactobacillus 30a., Gallagher T, Rozwarski DA, Ernst SR, Hackert ML, J Mol Biol. 1993 Mar 20;230(2):516-28. PMID:8464063
Page seeded by OCA on Thu Mar 20 13:30:34 2008
