2CWQ

Crystal structure of conserved protein TTHA0727 from Thermus thermophilus HB8

Summary for 2CWQ

• Entry DOI: 10.2210/pdb2cwq/pdb
• Descriptor: hypothetical protein TTHA0727 (2 entities in total)
• Functional Keywords: conserved hypothetical protein, all alpha, structural genomics, nppsfa, national project on protein structural and functional analyses, riken structural genomics/proteomics initiative, rsgi, unknown function
• Biological source: Thermus thermophilus
• Total number of polymer chains: 3
• Total formula weight: 45016.98

Authors

Ito, K.,Arai, R.,Fusatomi, E.,Kamo-Uchikubo, T.,Kawaguchi, S.,Terada, T.,Shirouzu, M.,Yokoyama, S.,RIKEN Structural Genomics/Proteomics Initiative (RSGI) (deposition date: 2005-06-23, release date: 2005-12-23, Last modification date: 2024-10-30)

Primary citation

Ito, K.,Arai, R.,Fusatomi, E.,Kamo-Uchikubo, T.,Kawaguchi, S.,Akasaka, R.,Terada, T.,Kuramitsu, S.,Shirouzu, M.,Yokoyama, S.
Crystal structure of the conserved protein TTHA0727 from Thermus thermophilus HB8 at 1.9 A resolution: A CMD family member distinct from carboxymuconolactone decarboxylase (CMD) and AhpD
Protein Sci., 15:1187-1192, 2006

PubMed Abstract: TTHA0727 is a conserved hypothetical protein from Thermus thermophilus HB8, with a molecular mass of 12.6 kDa. TTHA0727 belongs to the carboxymuconolactone decarboxylase (CMD) family (Pfam 02627). A sequence comparison with its homologs suggested that TTHA0727 is a distinct protein from alkylhydroperoxidase AhpD and gamma-carboxymuconolactone decarboxylase in the CMD family. Here we report the 1.9 A crystal structure of TTHA0727 (PDB ID: 2CWQ) determined by the multiwavelength anomalous dispersion method. The TTHA0727 monomer structure consists of seven alpha-helices (alpha1-alpha7) and one short 3(10)-helix. The crystal structure and the analytical ultracentrifugation revealed that TTHA0727 forms a hexameric ring structure in solution. The electrostatic potential distribution on the solvent-accessible surface of the TTHA0727 hexamer showed that positively charged regions exist on the side of the ring structure, suggesting that TTHA0727 interacts with some negatively charged molecules. A structural homology search revealed that the structure of three alpha-helices (alpha4-alpha6) is remarkably conserved, suggesting that it is the common structural motif for the CMD family proteins. In addition, the nine residues of the N-terminal tag bound to the cleft region between alpha1 and alpha3 in chains A and B of TTHA0727, implying that this region is the putative binding/active site for some small molecules.

PubMed: 16597838
DOI: 10.1110/ps.062148506

Experimental method

X-RAY DIFFRACTION (1.9 Å)