Pectin microgels and their subunit structure.
High-performance size exclusion chromatography revealed that alkaline-extracted peach fruit pectin dissolved in 0.05 M NaNO3 comprised a hierarchy of at least four aggregated, macromolecular-sized species. Each of the three largest species was found to be comparable in length to the three smallest subunits of an interconnecting gel network visualized by transmission electron microscopy of pectin, rapidly dried from solution. The interconnecting subunits of the gel network were rods or segmented rods and the integrated network formed a circular gel about 1 micron in diameter. Shadowed samples prepared from 5 and 50 mM NaCl or aqueous glycerol solutions produced images of partially dissociated subunits.
Fishman
M L
ML
Eastern Regional Research Center, U.S. Department of Agriculture, Philadelphia, Pennsylvania 19118.
Cooke
P
P
Levaj
B
B
Gillespie
D T
DT
Sondey
S M
SM
Scorza
R
R
D002851:Chromatography, High Pressure Liquid; D005638:Fruit; D005782:Gels / Q000737:chemistry*; D005990:Glycerol; D046911:Macromolecular Substances; D008854:Microscopy, Electron; D010368:Pectins / Q000737:chemistry*; D010944:Plants / Q000737:chemistry*; D012965:Sodium Chloride; D012996:Solutions
D005782:Gels; D046911:Macromolecular Substances; D012996:Solutions; D012965:Sodium Chloride; D010368:Pectins; D005990:Glycerol