Potassium native gellan

Potassium native gellan, 389-391,430-431 Pseudo-oligosaccharides, spirodioxanyl, 220-221 Pyramine... 

Fig. 36.—(a) Stereo view of about a turn of the 3-fold double helix of native gellan (42). The two chains are drawn in open and filled bonds for distinction. Both intra- and inter chain hydrogen bonds stabilize the helix. The vertical line is the helix axis. The potassium ions (crossed circles) have only half occupancy at each site. 

Figure 10. A stereo view of the native gellan double-helix and the coordinating potassium ions (filled circles) and water molecules (open circles). The intrachain (thin dashed lines), interchain (thick dashed lines) hydrogen bonds and ligands to potassium ions (thin lines) stabilize the double-helix. Both acetate and glycerate groups are shown along with their hydrogen atoms. (Reproduced with permission from Ref. 14. Copyright 1989 Elsevier.)...

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