Observation of the helical structure of the bacterial polysaccharide acetan by atomic force microscopy.
A method has been developed that has been found to give reproducible images of uncoated polysaccharides by Atomic Force Microscopy (AFM). Aqueous solutions of the polysaccharide are deposited as drops onto freshly cleaved mica surfaces, air dried, and then imaged under butanol. The method has been used to obtain images of the bacterial polysaccharide acetan. In regions within the deposited sample, where the molecules are aligned side-by-side, it has been possible to observe a periodic structure along the polysaccharide chain, attributable to the helical structure of acetan.
Kirby
A R
AR
Institute of Food Research, Colney, Norwich, United Kingdom.
Gunning
A P
AP
Morris
V J
VJ
Ridout
M J
MJ
D000091:Acetobacter / Q000737:chemistry; D055592:Biophysical Phenomena; D001703:Biophysics; D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D018625:Microscopy, Atomic Force / Q000379:methods*; D008969:Molecular Sequence Data; D015394:Molecular Structure; D011135:Polysaccharides, Bacterial / Q000737:chemistry* / Q000648:ultrastructure; D012996:Solutions; D014867:Water
D011135:Polysaccharides, Bacterial; D012996:Solutions; D014867:Water; C068545:acetan; C002563:xanthan gum