Mobility of the terminal regions of flagellin in solution.
The mobility of the disordered terminal regions of flagellin was examined in detail based on 1H NMR chemical shifts and spin-lattice relaxation times in the rotating frame. Proteolytic fragments of flagellin with terminal deletions of different sizes were used to compare the dynamical properties of various N- and C-terminal segments. We found that dynamic properties of different terminal segments were similar to each other and were close to those of the heat-denatured state of flagellin. The main chain of these terminal segments undergoes rapid motions with effective correlation times of 1.3-4.1 x 10(-9) s. The terminal regions contain no large segments with well-defined structure. However, comparison with the random-coiled state of poly-L-lysine suggests significant structural constraints in the terminal regions (as well as in the heat-denatured flagellin) which may reflect the existence of some highly fluctuating secondary structure, as suggested by earlier CD studies.
Ishima
R
R
Department of Chemistry, Faculty of Science, Kyoto University, Japan.
Akasaka
K
K
Aizawa
S
S
Vonderviszt
F
F
D000595:Amino Acid Sequence; D002942:Circular Dichroism; D005408:Flagellin / Q000737:chemistry*; D007700:Kinetics; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D008433:Mathematics; D008962:Models, Theoretical; D010446:Peptide Fragments / Q000737:chemistry; D011487:Protein Conformation; D011489:Protein Denaturation; D012486:Salmonella typhimurium; D012996:Solutions
D010446:Peptide Fragments; D012996:Solutions; D005408:Flagellin