Identification of the Mesorhizobium loti gene responsible for glycerophosphorylation of periplasmic cyclic β-1,2-glucans

Yasuyuki Kawaharada, Hiromasa Kiyota, Shima Eda, Kiwamu Minamisawa, Hisayuki Mitsui

Research output: Contribution to journalArticle

6 Citations (Scopus)


Periplasmic cyclic β-1,2-glucans play a crucial role in symbiosis as well as in hypo-osmotic adaptation for rhizobia. These glucans are modified in many species by anionic substituents such as glycerophosphoryl and succinyl ones, but their role remains to be examined. In this work, the cgmA homolog is shown to be responsible for glycerophosphorylation of cyclic β-1,2-glucans in Mesorhizobium loti. The mutation in cgmA converted most anionic glucans into neutral ones, leaving a small amount of succinylated ones. An additional mutation in opgC, which encodes a succinyltransferase homolog, abolished the residual succinyl substituents in the cgmA-mutant background. The double mutant in cgmA and opgC did not show any significant phenotypic differences from the wild type during both vegetative growth and symbiosis. It is concluded that the anionic substituents make a minor contribution, if any, to the effectiveness of cyclic β-1,2-glucans in M. loti.

Original languageEnglish
Pages (from-to)131-137
Number of pages7
JournalFEMS Microbiology Letters
Issue number2
Publication statusPublished - Jan 1 2010



  • Cyclic glucan
  • Legume symbiosis
  • Lotus japonicus
  • Mesorhizobium loti
  • Phosphoglycerol

ASJC Scopus subject areas

  • Microbiology
  • Molecular Biology
  • Genetics

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