Agglutination of Erwinia stewartii Strains with a Corn Agglutinin: Correlation with Extracellular Polysaccharide Production and Pathogenicity

作者：J. J. Bradshaw-Rouse, Marianmne Whatley, D. L. Coplin, A. Edwin Woods, Luis Sequeira, ARTHUR KELMAN · 发表于：Applied and Environmental Microbiology · 年份：1981 · DOI：10.1128/aem.42.2.344-350.1981 · 被引用次数：59 · 研究领域：Plant Pathogenic Bacteria Studies、Sugarcane Cultivation and Processing、Irrigation Practices and Water Management

A bacterial agglutinin was extracted from ground corn (WI hybrid 64A x W117) seed with phosphate-buffered saline (pH 6.0) and precipitated with (NH(4))(2)SO(4) at 70% saturation. The activities of this agglutinin against 22 strains of Erwinia stewartii (agent of bacterial wilt of corn) that varied in virulence were determined. Specific agglutination (agglutination titer per milligram of protein per milliliter) values were correlated negatively with virulence ratings. Strains with high specific agglutination values (15 or higher) were avirulent or weakly virulent; strains with low specific agglutination values (10 or lower) were highly virulent, with two exceptions. Avirulent strains produced butyrous colonies and released only small amounts of extracellular polysaccharide (EPS) into the medium, and the cells lacked capsules; virulent strains produced fluidal colonies and released large amounts of EPS, and the cells were capsulated. There was a strong correlation between the amount of EPS produced by each strain (as determined by increase in viscosity of the medium) and the specific agglutination value; in contrast, lipopolysaccharide compositions were similar in all strains. When cells of six fluidal strains were washed by repeatedly centrifuging and resuspending them in buffer, they were agglutinated more strongly by corn agglutinin than were unwashed cells. When avirulent cells were washed, their specific agglutination values did not increase significantly. Eight EPS-defici...