Characterization of metal binding properties of rhamnogalacturonan II from plant cell walls by size-exclusion HPLC/ICP-MS.
The binding properties of metal ions to a pectic polysaccharide, rhamnogalacturonan II (RG-II), from plant cell walls were analyzed by size-exclusion HPLC/ICP-MS. The dimeric RG-II borate complex (dRG-II-B) from sugar beet and red wine contained 0.8 - 1.1 mol/mol of B, 0.8 - 1.1 mol/mol of Ca, 0.1 - 0.3 mol/mol of Sr, and 0.03 - 0.07 mol/mol of Ba. The treatment of dRG-II-B with Sr2+, Ba2+, Pb2+ or La3+ exchanged the originally present Ca, Sr and Ba. In contrast, monomeric RG-II (mRG-II), which contained approximately 0.1 mol/mol of Ca, formed complexes with La3+, Eu3+, and Lu3+ added to the solution, but did not do so with Ca2+, Sr2+, Ba2+ and Pb2+. The HPLC/ICP-MS and HPLC/RI (refractive index detector) analysis of the partially hydrolyzed mRG-II that was treated with La3+ indicated that the side chains and backbone of mRG-II together form a lanthanoid binding site.
Matsunaga
Toshiro
T
National Agricultural Research Center for Kyushu Okinawa Region, Nishigoshi, Kumamoto 861-1192, Japan. tmatunag@affrc.go.jp
Ishii
Tadashi
T
D001881:Borates / Q000032:analysis / Q000737:chemistry; D002473:Cell Wall / Q000737:chemistry*; D002850:Chromatography, Gel / Q000379:methods; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D013058:Mass Spectrometry / Q000379:methods; D008670:Metals / Q000032:analysis / Q000737:chemistry*; D010368:Pectins / Q000032:analysis / Q000737:chemistry*; D010944:Plants
D001881:Borates; D008670:Metals; C042492:rhamnogalacturonan II; D010368:Pectins