Crude side tomato lectins for identification of group B beta-hemolytic streptococci.

ABSTRACT

Crude extracte from the side tomato fruit have been shown to contain lectins which specifically bind to group B Beta-hemolytic streptococci. Some additional properties of crude lectins were investigated. The lectins could agglutinate human erythrocytes of type A,B and O. Agglutination was enhanced by trypsin treatment of erythrocytes. The carbohtydrate-binding specificity indicated a specificity of tri-acetyl-glucosamine. They were stable at a high temperature and had a long half-life. The crude lectins agglutinated 149 to 160 strains of group B Beta-hemolytic streptococci with 93.1 percent sensitivity, and did not react with any other of 150 streptococcal sergroups (100% specificity). This finding indicates that the test using crude Sida tomato lectins offers some profound sensitive agglutination technique, they may provide a suitable alternative to other conventional tests for a rapid, simple, cost-effective and specific differentiation of group B from other of Beta-hemolytic streptococci on primary isolation.