Crystal structure of AGR_C_4470p from Agrobacterium tumefaciens

• Published in: Protein science Vol. 16; no. 3; pp. 535 - 538
• Main Authors: Vorobiev, Sergey M., Neely, Helen, Seetharaman, Jayaraman, Ma, Li‐Chung, Xiao, Rong, Acton, Thomas B., Montelione, Gaetano T., Tong, Liang
• Format: Journal Article
• Language: English
• Published: Bristol Cold Spring Harbor Laboratory Press 01-03-2007
• Subjects: Agrobacterium tumefaciens; Agrobacterium tumefaciens - metabolism; Amino Acid Sequence; BACTERIA; Bacterial Proteins - chemistry; Binding Sites; ChuS; Conserved Sequence; CRYSTAL STRUCTURE; Crystallography, X-Ray; Dimerization; DIMERS; ESCHERICHIA COLI; gene duplication; GENES; HEME; Heme Oxygenase (Decyclizing) - chemistry; heme utilization enzyme; HemS; MATERIALS SCIENCE; Membrane Transport Proteins - chemistry; Models, Molecular; molecular evolution; Molecular Sequence Data; national synchrotron light source; Oxidoreductases - chemistry; Protein Conformation; protein structure; Protein Structure Report; PROTEINS; Sequence Alignment; structural genomics; Yersinia enterocolitica
• ISSN: 0961-8368; 1469-896X
• DOI: 10.1110/ps.062663307

We report here the crystal structure at 2.0 Å resolution of the AGR_C_4470p protein from the Gram‐negative bacterium Agrobacterium tumefaciens. The protein is a tightly associated dimer, each subunit of which bears strong structural homology with the two domains of the heme utilization protein ChuS from Escherichia coli and HemS from Yersinia enterocolitica. Remarkably, the organization of the AGR_C_4470p dimer is the same as that of the two domains in ChuS and HemS, providing structural evidence that these two proteins evolved by gene duplication. However, the binding site for heme, while conserved in HemS and ChuS, is not conserved in AGR_C_4470p, suggesting that it probably has a different function. This is supported by the presence of two homologs of AGR_C_4470p in E. coli, in addition to the ChuS protein.