TY - JOUR
T1 - Sugars communicate through water
T2 - Oriented glycans induce water structuring
AU - Espinosa-Marzal, Rosa M.
AU - Fontani, Giacomo
AU - Reusch, Frieder B.
AU - Roba, Marcella
AU - Spencer, Nicholas D.
AU - Crockett, Rowena
N1 - Funding Information:
This work was supported by the Swiss National Science Foundation.
PY - 2013/6/18
Y1 - 2013/6/18
N2 - Cells are coated with a glycocalyx - a layer of carbohydrate-containing biomolecules, such as glycoproteins. Although the structure and orientation of the cell-surface glycans are frequently regarded as being random, we have found, using α-1-acid glycoprotein and antitrypsin as model systems for surface glycans, that this is not the case. A glycoprotein monolayer was adsorbed onto hydrophilic and hydrophobic substrates. Surface-force measurements revealed that the orientation of the glycans with respect to the aqueous solution has a profound effect on the structure of vicinal water. The glycan antennae of the surface-adsorbed glycoproteins apparently impose an ordering on the water, resulting in a strong repulsive force over some tens of nanometers with superposed film-thickness transitions ranging from ≈0.7 to 1.8 nm. When the glycan orientation is modified by chemical means, this long-range repulsion disappears. These results may provide an explanation as to why the multiantennary structure is ubiquitous in glycoproteins. Although direct, specific interactions between glycans and other biomolecules are essential for their functionality, these results indicate that glycans' long-range structuring of water may also influence their ability to interact with biomolecules in their vicinity.
AB - Cells are coated with a glycocalyx - a layer of carbohydrate-containing biomolecules, such as glycoproteins. Although the structure and orientation of the cell-surface glycans are frequently regarded as being random, we have found, using α-1-acid glycoprotein and antitrypsin as model systems for surface glycans, that this is not the case. A glycoprotein monolayer was adsorbed onto hydrophilic and hydrophobic substrates. Surface-force measurements revealed that the orientation of the glycans with respect to the aqueous solution has a profound effect on the structure of vicinal water. The glycan antennae of the surface-adsorbed glycoproteins apparently impose an ordering on the water, resulting in a strong repulsive force over some tens of nanometers with superposed film-thickness transitions ranging from ≈0.7 to 1.8 nm. When the glycan orientation is modified by chemical means, this long-range repulsion disappears. These results may provide an explanation as to why the multiantennary structure is ubiquitous in glycoproteins. Although direct, specific interactions between glycans and other biomolecules are essential for their functionality, these results indicate that glycans' long-range structuring of water may also influence their ability to interact with biomolecules in their vicinity.
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U2 - 10.1016/j.bpj.2013.05.017
DO - 10.1016/j.bpj.2013.05.017
M3 - Article
C2 - 23790377
AN - SCOPUS:84879246561
SN - 0006-3495
VL - 104
SP - 2686
EP - 2694
JO - Biophysical journal
JF - Biophysical journal
IS - 12
ER -