Crystal structure of the C-terminal domain of a flagellar hook-capping protein from Xanthomonas campestris.
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.
Kuo
Wei-Ting
WT
Institute of Biochemistry, National Chung-Hsing University, Taichung, 40227, Taiwan, Republic of China.
Chin
Ko-Hsin
KH
Lo
Wen-Ting
WT
Wang
Andrew H-J
AH
Chou
Shan-Ho
SH
D020816:Amino Acid Motifs; D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D018360:Crystallography, X-Ray; D005353:Fibronectins / Q000737:chemistry / Q000378:metabolism; D005407:Flagella / Q000378:metabolism*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D016959:Xanthomonas campestris / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*
D001426:Bacterial Proteins; D005353:Fibronectins