2w6r
From Proteopedia
Crystal structure of an artificial (ba)8-barrel protein designed from identical half barrels
Structural highlights
FunctionHIS6_THEMA IGPS catalyzes the conversion of PRFAR and glutamine to IGP, AICAR and glutamate. The HisF subunit catalyzes the cyclization activity that produces IGP and AICAR from PRFAR using the ammonia provided by the HisH subunit.[HAMAP-Rule:MF_01013] Evolutionary ConservationCheck, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedAmple evidence suggests that the ubiquitous (betaalpha)(8)-barrel enzyme fold has evolved by the duplication and fusion of an ancestral (betaalpha)(4)-half-barrel. To reconstruct this process in the laboratory with a model protein, we earlier fused two copies of the C-terminal half-barrel HisF-C of imidazole glycerol phosphate synthase (HisF) and stepwise stabilized the resulting HisF-CC construct. We now further increased its stability and solubility by introducing two additional amino acid exchanges, which allowed us to crystallize the resulting artificial (betaalpha)(8)-barrel protein HisF-C***C. The analysis of its X-ray structure at 2.1 A resolution reveals a striking similarity to wild-type HisF, helps us to understand its improved stability, and provides further insights into the evolution of (betaalpha)(8)-barrel proteins. High-Resolution Crystal Structure of an Artificial (betaalpha)(8)-Barrel Protein Designed from Identical Half-Barrels (dagger) (double dagger).,Hocker B, Lochner A, Seitz T, Claren J, Sterner R Biochemistry. 2009 Jan 23. PMID:19166324[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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