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1u11
From Proteopedia
PurE (N5-carboxyaminoimidazole Ribonucleotide Mutase) from the acidophile Acetobacter aceti
Overview
The crystal structure of Acetobacter aceti PurE was determined to a resolution of 1.55 A and is compared with the known structures of the class I PurEs from a mesophile, Escherichia coli, and a thermophile, Thermotoga maritima. Analyses of the general factors that increase protein stability are examined as potential explanations for the acid stability of A. aceti PurE. Increased inter-subunit hydrogen bonding and an increased number of arginine-containing salt bridges appear to account for the bulk of the increased acid stability. A chain of histidines linking two active sites is discussed in the context of the proton transfers catalyzed by the enzyme.
About this Structure
Full crystallographic information is available from OCA.
Reference
Acidophilic adaptations in the structure of Acetobacter aceti N5-carboxyaminoimidazole ribonucleotide mutase (PurE)., Settembre EC, Chittuluru JR, Mill CP, Kappock TJ, Ealick SE, Acta Crystallogr D Biol Crystallogr. 2004 Oct;60(Pt 10):1753-60. Epub 2004, Sep 23. PMID:15388921 Page seeded by OCA on Sat May 3 10:37:12 2008
