Measurement of the length of the a helical section of a peptide directly using atomic force microscopy.
Chem Pharm Bull (Tokyo)
; 49(12): 1512-6, 2001 Dec.
Article
de En
| MEDLINE
| ID: mdl-11767067
ABSTRACT
Using atomic force microscopy (AFM), the length of the alpha-helix structure of poly-L-lysine was investigated by stretching the peptide directly, one molecule at a time. In the absence of urea, many rupturing points that seemed to be due to the breaking of some hydrogen bonds were observed in force-extension curves, while these points were never observed in the presence of 8 M urea. In the presence of 0.4 or 1.6 M urea, both force-extension curve types were observed. Total peptide elongation for each condition was calculated from force-extension curves reflecting the alpha-helix rupturing process. The experimental value of total elongation divided by the theoretical value of total alpha-helix elongation yields the alpha-helix content. This value was compatible with circular dichroism (CD) measurement results. This suggests that peptide conformation and content of the alpha-helix on a single molecule scale can be investigated by direct mechanical measurement using atomic force microscopy.
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Collection:
01-internacional
Base de données:
MEDLINE
Sujet principal:
Peptides
Langue:
En
Journal:
Chem Pharm Bull (Tokyo)
Année:
2001
Type de document:
Article
Pays d'affiliation:
Japon