1. Exopolysaccharide production by nitrogen-fixing bacteria within nodules of Medicago plants exposed to chronic radiation in the Chernobyl exclusion zone.
- Author
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Pawlicki-Jullian N, Courtois B, Pillon M, Lesur D, Le Flèche-Mateos A, Laberche JC, Goncharova N, and Courtois J
- Subjects
- Chernobyl Nuclear Accident, DNA, Bacterial chemistry, DNA, Bacterial genetics, DNA-Directed RNA Polymerases genetics, Enterobacteriaceae classification, Enterobacteriaceae isolation & purification, Enterobacteriaceae radiation effects, Fucose analysis, Galactose analysis, Glucose analysis, Glucuronic Acid analysis, Magnetic Resonance Spectroscopy, Mannose analysis, Medicago radiation effects, Molecular Sequence Data, Molecular Weight, Polysaccharides, Bacterial chemistry, Republic of Belarus, Sequence Analysis, DNA, Sinorhizobium meliloti classification, Sinorhizobium meliloti isolation & purification, Sinorhizobium meliloti radiation effects, Enterobacteriaceae metabolism, Medicago microbiology, Polysaccharides, Bacterial metabolism, Root Nodules, Plant microbiology, Sinorhizobium meliloti metabolism
- Abstract
Nitrogen-fixing bacteria isolated from root nodules of Medicago plants growing in the 10 km zone around the Chernobyl nuclear power plant were screened for the production of new water-soluble acidic exopolysaccharides (EPSs). The different strains belonged to the Enteriobacteriaceae family (Enterobacter ludwigii, Raoultella terrigena, Klebsiella oxytoca), except for one which belonged to the Rhizobiaceae family (Sinorhizobium meliloti). All of the bacteria produced highly viscous EPS with an average molecular weight comprised between 1 x 10(6) and 3 x 10(6) Da. Five different compositions of EPS were characterized by physico-chemical analyses and (1)H NMR spectroscopy: galactose/mannose (2/1), galactose/glucose (1/1), galactose/glucose/mannose (1/2/1), fucose/galactose/glucose (2/1/1) and fucose/galactose/glucose/mannose (2/2/1/1 or 1/1/2/4). Glucuronic acid, a charged monosaccharide, was also recovered in most of the different EPSs., (Copyright 2010 Elsevier Masson SAS. All rights reserved.)
- Published
- 2010
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