Production of an extracellular polysaccharide by Agrobacterium sp DS3 NRRL B-14297 isolated from soil.
A bacterium isolated from soil and identified as Agrobacterium sp produced a water-soluble extracellular polysaccharide capable of producing highly viscous solutions. Gas chromatographic analysis revealed a sugar composition of glucose, galactose and mannose in the molar ratio of 7.5:2.4:1, together with 3.7% (w/w) pyruvic acid. Methylation analyses showed the presence of (1-->3)-, (1-->4)- and (1-->6)-linked glucose, (1-->3)- and (1-->4, 1-->6)-linked galactose and a small portion of (1-->3)-linked mannose residues. Succinic acid was not present. The molecular weight of the polysaccharide was estimated by light scattering to be 2 x 10(6) Da. The viscosity of solutions containing the polysaccharide remained constant from pH 3 to 11, and decreased by 50% when heated from 5 to 55 degrees C. Maximum yield of the polysaccharide, 20 g L-1, was reached in 48 h at 30 degrees C incubation.
Hou
C T
CT
Oil Chemical Research Unit, National Center for Agricultural Utilization Research, USDA, Peoria, IL 61604, USA.
Ahlgren
J A
JA
Brown
W
W
Nicholson
J J
JJ
D002236:Carbohydrate Conformation; D002855:Chromatography, Thin Layer; D005690:Galactose / Q000032:analysis; D008401:Gas Chromatography-Mass Spectrometry; D005947:Glucose / Q000032:analysis; D008358:Mannose / Q000032:analysis; D008970:Molecular Weight; D011135:Polysaccharides, Bacterial / Q000096:biosynthesis* / Q000737:chemistry* / Q000302:isolation & purification; D012231:Rhizobium / Q000302:isolation & purification / Q000378:metabolism*; D012988:Soil Microbiology
D011135:Polysaccharides, Bacterial; D005947:Glucose; D008358:Mannose; D005690:Galactose