ExoA is involved in the biosynthesis of succinoglycan. Succinoglycan Biosynthesis Protein ExoA catalyzes the formation of a beta-1,3 linkage of the second sugar (glucose) of the succinoglycan with the galactose on the lipid carrie. Succinoglycan is an acidic exopolysaccharide that is important for invasion of the nodules. Succinoglycan is a high-molecular-weight polymer composed of repeating octasaccharide units. These units are synthesized on membrane-bound isoprenoid lipid carriers, beginning with galactose followed by seven glucose molecules, and modified by the addition of acetate, succinate, and pyruvate. ExoA is a membrane protein with a transmembrance domain at c-terminus.

Glycosyltransferase, catalytic subunit of cellulose synthase and poly-beta-1,6-N-acetylglucosamine synthase [Cell motility].

Glycosyl transferase family 2. Diverse family, transferring sugar from UDP-glucose, UDP-N-acetyl- galactosamine, GDP-mannose or CDP-abequose, to a range of substrates including cellulose, dolichol phosphate and teichoic acids.