Analysis of the molecular size of tomato (Lycopersicon esculentum Mill) fruit polyuronides by gel filtration and low-speed sedimentation equilibrium.
The cell-wall structures of tomato (Lycopersicon esculentum Mill) and other fruit are intimately linked with the nature of their polyuronides. Cell-wall polyuronides from unripe and ripe tomato fruit were isolated and purified and their molecular size and molecular-size distributions were compared. It was demonstrated that there is a considerable decrease in the weight-average Mr upon ripening (from 160,000 +/- 10,000 to 96,000 +/- 4000) and a corresponding increase in polydispersity, particularly at the low-Mr end of the distribution. The estimates of polyuronide molecular size and molecular-size distribution were obtained without the need for polyuronide standards of known Mr by using gel-filtration chromatography combined with the absolute method of low-speed sedimentation equilibrium.
Seymour
G B
GB
Department of Applied Biochemistry & Food Science, University of Nottingham, Loughborough, Leics, U.K.
Harding
S E
SE
D002499:Centrifugation, Density Gradient; D002850:Chromatography, Gel; D008970:Molecular Weight; D010944:Plants / Q000032:analysis*; D014574:Uronic Acids / Q000032:analysis*
D014574:Uronic Acids; C018402:traumacel