Effect of various peptide and polysaccharide acceptor substrates on incorporation of 14C-radiolabeled galactose.
A, permeabilized microsomal membranes from the NC Pichia line transformed with the empty expression vector and the C2 Pichia line expressing His6-AtGALT2 served as the enzyme source in the GALT reactions. (AO)7, (AO)14, and d(AO)51 contain 7, 14, and 51 AO units, respectively. A chemically synthesized extensin peptide (ExtP) contains repetitive SO4 units. (AP)7 contains seven AP units. Rhamnogalactan I (RGI) from potato and rhamnogalactan (RG) from soybean represent pectin polymer substrates. Enzyme reactions were done in triplicate, and mean values are presented. Error bars, S.E.