Accumulation of Soybean Lectin-Binding Polysaccharide During Growth of Rhizobium japonicum as Determined by Hemagglutination Inhibition Assay

A hemagglutination inhibition assay was used to estimate the presence of soybean lectin-binding polysaccharide in whole culture, culture supernatant, and isolated exopolysaccharide of Rhizobium japonicum USDA 138. The occurrence of 0.1 to 0.2 μg of lectin-binding polysaccharide could be detected within 2 h with a 0.5-ml total sample. Lectin-binding polysaccharide was detected in all preparations during both exponential and stationary growth phases. The formation of lectin-binding polysaccharide was not, whereas that of total exopolysaccharide was, markedly affected by culture conditions.