Regulation of succinoglycan and galactoglucan biosynthesis in Sinorhizobium meliloti

J Mol Microbiol Biotechnol. 2002 May;4(3):187-90.


Sinorhizobium meliloti (Rhizobium meliloti) 2011 has the ability to produce the two acidic exopolysaccharides succinoglycan (EPS I) and galactoglucan (EPS II). EPS I is a branched heteropolysaccharide composed of octasaccharide repeating units, whereas EPS II is a linear heteropolysaccharide consisting of disaccharide subunits. The exo-exs and exp gene clusters are involved in the biosynthesis of EPSI and EPSII, respectively. EPSI and EPSII biosynthesis genes are differentially expressed resulting in a complex regulation of EPS production in S. meliloti. The phosphate concentration was identified as an important factor affecting the expression of exp genes.

Publication types

  • Review

MeSH terms

  • Bacterial Proteins / genetics*
  • Bacterial Proteins / metabolism
  • Galactans*
  • Gene Expression Regulation, Bacterial*
  • Genes, Bacterial
  • Glucans*
  • Multigene Family
  • Polysaccharides, Bacterial / biosynthesis*
  • Sinorhizobium meliloti / genetics
  • Sinorhizobium meliloti / growth & development
  • Sinorhizobium meliloti / metabolism*
  • Transcription, Genetic


  • Bacterial Proteins
  • Galactans
  • Glucans
  • Polysaccharides, Bacterial
  • galactoglucan
  • succinoglycan