In vitro biosynthesis of 1,4-beta-galactan attached to a pectin-xyloglucan complex in pea.
Particulate enzyme preparations were prepared from etiolated pea ( Pisum sativum L.) epicotyls and used to assay for 1,4-beta-galactan synthase using UDP-[U-(14)C]galactose. Optimum conditions for 1,4-beta-galactan synthesis were determined. The enzyme products were characterized by selective enzymic degradation, gel permeation chromatography and anion-exchange chromatography. Evidence was obtained for the formation of 1,4-beta-galactan chain attached to a pectic backbone containing both polygalacturonic acid and rhamnogalacturonan I. The results also indicated that part or all of this nascent pectin was present as a complex with xyloglucan.
Abdel-Massih
Roula M
RM
Department of Biology, American University of Beirut, Beirut, Lebanon.
Baydoun
Elias A H
EA
Brett
Christopher T
CT
D002250:Carbon Radioisotopes; D002852:Chromatography, Ion Exchange; D005685:Galactans / Q000096:biosynthesis*; D005936:Glucans; D006026:Glycoside Hydrolases; D006056:Golgi Apparatus / Q000378:metabolism; D018532:Pisum sativum / Q000201:enzymology*; D010368:Pectins / Q000378:metabolism*; D011108:Polymers / Q000378:metabolism; D011134:Polysaccharides / Q000378:metabolism*; D014990:Xylans; D001616:beta-Galactosidase / Q000378:metabolism
C411147:1,4-beta-galactan; D002250:Carbon Radioisotopes; D005685:Galactans; D005936:Glucans; D011108:Polymers; D011134:Polysaccharides; D014990:Xylans; C042491:rhamnogalacturonan I; C029353:xyloglucan; D010368:Pectins; D006026:Glycoside Hydrolases; C089138:beta-galactanase; D001616:beta-Galactosidase; C003181:polygalacturonic acid