- The Sinorhizobium meliloti ExpE1 protein secreted by a type I secretion system involving ExpD1 and ExpD2 is required for biosynthesis or secretion of the exopolysaccharide galactoglucan. Moreira, L.M., Becker, J.D., Pühler, A., Becker, A. Microbiology (Reading, Engl.) (2000)









