Taxonomic group: fungi / Ascomycota
(Phylum: Ascomycota)
NCBI PubMed ID: 15345528Publication DOI: 10.1529/biophysj.104.042879Journal NLM ID: 0370626Publisher: Cambridge, MA: Cell Press
Correspondence: Marszalek PE <pemar
duke.edu>
Institutions: Department of Mechanical Engineering and Materials Science, Duke University, Durham, USA, Center for Bioinspired Materials and Material Systems, Duke University, Durham, USA, Institute of Physics, Nicholaus Copernicus University, Toruń, Poland
Recent atomic force microscopy stretching measurements of single polysaccharide molecules suggest that their elasticity is governed by force-induced conformational transitions of the pyranose ring. However, the mechanism of these transitions and the mechanics of the pyranose ring are not fully understood. Here we use steered molecular dynamics simulations of the stretching process to unravel the mechanism of forced conformational transitions in 1,6 linked polysaccharides. In contrast to most sugars, 1,6 linked polysaccharides have an extra bond in their inter-residue linkage, C5-C6, around which restricted rotations occur and this additional degree of freedom increases the mechanical complexity of these polymers. By comparing the computational results with the atomic force microscopy data we determine that forced rotations around the C5-C6 bond have a significant and different impact on the elasticity of α- and β-linked polysaccharides. β-linkages of a polysaccharide pustulan force the rotation around the C5-C6 bonds and produce a Hookean-like elasticity but do not affect the conformation of the pyranose rings. However, α-linkages of dextran induce compound conformational transitions that include simultaneous rotations around the C5-C6 bonds and chair-boat transitions of the pyranose rings. These previously not-recognized transitions are responsible for the characteristic plateau in the force-extension relationship of dextran
molecular dynamics, Glucans, atomic force microscopy, Dextran
Structure type: homopolymer
Location inside paper: p. 1457, right column, paragraph 1
Trivial name: pustulan, β-1,6-glucan, β-1,6-D-glucan, β(1-6)-D-glucan, β-(1,6)-glucan, lasiodiplodan, pustulan, β-(1,6)-glucan, lasiodiplodan, β-(1,6)-glucan, β-(1,6)-glucan, lasiodiplodan, pustulan, β-1,6-glucan, β-(1,6)-glucan, pustulan, β-(1→6)-glucan PCPS, water-soluble glucan (PS-I)
Compound class: EPS, O-polysaccharide, cell wall polysaccharide, glycoprotein, glucan, polysaccharide, cell wall glucoprotein
Contained glycoepitopes: IEDB_135614,IEDB_141806,IEDB_142488,IEDB_146664,IEDB_241101,IEDB_983931,SB_192
Methods: molecular modeling, AFM
3D data: conformation data, dynamics
Related record ID(s): 7724, 8325, 42140, 43301, 43379, 44888, 44927, 44939, 45578, 47842, 47844, 48303, 48366, 48412, 48423, 48443, 49291, 101372, 124916, 138263, 143680, 143682, 149870
NCBI Taxonomy refs (TaxIDs): 136370Reference(s) to other database(s): GTC:G26777BZ, GlycomeDB:
863, CCSD:
50854, CBank-STR:4234
Show glycosyltransferases
There is only one chemically distinct structure:
Found 
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