Genetics and biochemistry of the Rhizobium meliloti acidic extracellular heteropolysaccharide and its role in nodulation: Annual report for the period 1 June 1986-31 May 1987
This document briefly describes studies of the genetics and biochemistry of Rhizobium meliloti exopolysaccharides and their role in alfalfa root nodule formation. Previously the author demonstrated that a large set of mutants (Exo/sup -/) of R. meliloti failed to secrete succinoglycan, an acidic exopolysaccharide of known structure. These mutations belonged to five different loci in the R. meliloti genome. All of the mutants shared the inability to enter alfalfa root nodules, providing strong correlative evidence that succinoglycan is involved in a certain phase in nodule development. In the past year, this research group characterized mutants that were previously designated ''haloless'' mutants. These mutants were thought to be unable to degrade the secreted polysaccharide into diffusible fragments that ordinarily form a halo of binding of a polysaccharide specific dye surrounding a colony of growth. The research team discovered a second acidic exopolysaccharide that is synthesized by certain mutant derivatives of our strain of R. meliloti. This polysaccharide appeared quite distinct from succinoglycan by NMR spectroscopy and appeared to replace succinoglycan in a Tn5-induced mutant called ''halo-clearing'', and in wild type strains containing a certain cosmid from the R. meliloti clone bank. 2 figs.
- Research Organization:
- Washington Univ., Seattle (USA)
- DOE Contract Number:
- FG06-86ER13532
- OSTI ID:
- 6429880
- Report Number(s):
- DOE/ER/13532-1; ON: DE87011076
- Resource Relation:
- Other Information: Portions of this document are illegible in microfiche products
- Country of Publication:
- United States
- Language:
- English
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A second exopolysaccharide of Rhizobium meliloti strain SU47 that can function in root nodule invasion
Genetics and biochemistry of the Rhizobium meliloti acidic extracellular heteropolysaccharide and its role in nodulation: Annual report for the period 1 June 1987-31 May 1988
Related Subjects
59 BASIC BIOLOGICAL SCIENCES
POLYSACCHARIDES
BIOLOGICAL FUNCTIONS
LIQUID COLUMN CHROMATOGRAPHY
ALFALFA
CELL WALL
GENE MUTATIONS
MYCORRHIZAS
NITRIFICATION
RHIZOBIUM
ROOTS
SYMBIOSIS
BACTERIA
CARBOHYDRATES
CELL CONSTITUENTS
CHEMICAL REACTIONS
CHROMATOGRAPHY
FUNCTIONS
LEGUMINOSAE
MICROORGANISMS
MUTATIONS
ORGANIC COMPOUNDS
PLANTS
SACCHARIDES
SEPARATION PROCESSES
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