Crystal structure of the C-terminal domain of a flagellar hook-capping protein from Xanthomonas campestris
Kuo, W.-T., Chin, K.-H., Lo, W.-T., Wang, A.H.-J., Chou, S.-H.(2008) J Mol Biol 381: 189-199
- PubMed: 18599076 
- DOI: https://doi.org/10.1016/j.jmb.2008.05.083
- Primary Citation of Related Structures:  
3C12 - PubMed Abstract: 
The crystal structure of the C-terminal domain of a hook-capping protein FlgD from the plant pathogen Xanthomonas campestris (Xc) has been determined to a resolution of ca 2.5 A using X-ray crystallography. The monomer of whole FlgD comprises 221 amino acids with a molecular mass of 22.7 kDa, but the flexible N-terminus is cleaved for up to 75 residues during crystallization. The final structure of the C-terminal domain reveals a novel hybrid comprising a tudor-like domain interdigitated with a fibronectin type III domain. The C-terminal domain of XcFlgD forms three types of dimers in the crystal. In agreement with this, analytical ultracentrifugation and gel filtration experiments reveal that they form a stable dimer in solution. From these results, we propose that the Xc flagellar hook cap protein FlgD comprises two individual domains, a flexible N-terminal domain that cannot be detected in the current study and a stable C-terminal domain that forms a stable dimer.
Organizational Affiliation: 
Institute of Biochemistry, National Chung-Hsing University, Taichung, 40227, Taiwan, Republic of China.