Journal of Biosciences

, Volume 20, Issue 1, pp 17–28

Pleiotropic effects of purine auxotrophy inRhizobium meliloti on cell surface molecules

  • S. K. Swamynathan
  • Aqbal Singh

DOI: 10.1007/BF02711577

Cite this article as:
Swamynathan, S.K. & Singh, A. J Biosci (1995) 20: 17. doi:10.1007/BF02711577


Rhizobial purine auxotrophs have earlier been shown to be defective in symbiosis, though the exact reason for this failure is not clear. Using various dyes that specifically bind different cell surface molecules, we show that there are multiple changes in the cell surface molecules associated with different purine auxotrophs. Affected molecules in different purine auxotrophs that were tested include (i) acidic exopolysaccharides, (ii) cellulose fibrils, and (iii) beta (1–3) glucans. Our results show that the symbiotic deficiency of purine auxotrophs is likely to be a result of these associated changes on the cell surface


Rhizobium melilotiMedicago salivapurine biosynthesisexopolysaccharidessymbiosis

Copyright information

© Indian Academy of Sciences 1995

Authors and Affiliations

  • S. K. Swamynathan
    • 1
  • Aqbal Singh
    • 1
  1. 1.Biotechnology CentreIndian Agricultural Research InstituteNew DelhiIndia
  2. 2.Centre for Cellular and Molecular BiologyHyderabadIndia