NOD FACTORS OF AZORHIZOBIUM-CAULINODANS STRAIN ORS571 CAN BE GLYCOSYLATED WITH AN ARABINOSYL GROUP, A FUCOSYL GROUP, OR BOTH

In addition to the previously described arabinosylated Nod factors, Az orhizobium caulinodans can also produce fucosylated Nod factors and No d factors that are both arabinosylated and fucosylated. The presence o f a plasmid carrying extra copies of a subset of nod genes as well as bacterial growth conditions influence the relative proportion of carba moylated, fucosylated, and arabinosylated Nod factors, By using a root hair formation assay, we demonstrate that the Nod factor glycosylatio ns are important for biological activity on Sesbania rostrata roots.