Effects of salts on production and on O-acetylation of glucuronan excreted by the Rhizobium meliloti M5N1 CS strain.
Acetylation determined by 1H-nuclear magnetic resonance spectroscopy and production of the glucuronan excreted by the Rhizobium meliloti M5N1CS strain during cultivation in RCS medium with and without added magnesium salts have been studied. These salts induce an increase in the degree of substitution and the molar ratio of 2,3-di-O-acetyl residues. A decrease in production is observed after 75 h of fermentation as the magnesium salt concentration increases. The presence of manganese and sodium salts in the culture induces inhibition of exopolysaccharide (EPS) production. However, the structure of the EPS is similar to that of the EPS produced by standard fermentation, without modification in the degree of substitution.
Roblot
C
C
Laboratoire de Génie Cellulaire, Université de Picardie Jules Verne, Amiens, France.
Séguin
J P
JP
Barbotin
J N
JN
Michaud
P
P
Courtois
J
J
Courtois
B
B
Heyraud
A
A
D000107:Acetylation / Q000187:drug effects; D002712:Chlorides / Q000494:pharmacology*; D005285:Fermentation; D015636:Magnesium Chloride / Q000494:pharmacology*; D008278:Magnesium Sulfate / Q000494:pharmacology*; D009682:Magnetic Resonance Spectroscopy; D017895:Manganese Compounds / Q000494:pharmacology*; D011134:Polysaccharides / Q000378:metabolism*; D011135:Polysaccharides, Bacterial / Q000378:metabolism*; D012492:Salts / Q000494:pharmacology; D016962:Sinorhizobium meliloti / Q000187:drug effects* / Q000378:metabolism; D013431:Sulfates / Q000494:pharmacology*
D002712:Chlorides; D017895:Manganese Compounds; D011134:Polysaccharides; D011135:Polysaccharides, Bacterial; D012492:Salts; D013431:Sulfates; D015636:Magnesium Chloride; C012036:sodium sulfate; C088556:mucoric acid; D008278:Magnesium Sulfate; C025340:manganese chloride; C039798:manganese sulfate