Physico-chemical surface properties of Shigella sonnei

In partition in two-phase systems as well as in hydrophobic and ion exchange chromatography a number of Sh. sonnei isolates with different phage patterns showed similar physico-chemical surface properties. All the isolates displayed hydrophobicity and a small negative charge. In this way the shigellae were different from salmonella S-strains and E. coli strains associated with infantile diarrhoea which have shown hydrophilic properties and nearly no charge. They were also different from E. coli strains with typical K-antigen often grown from patients with septicemia and upper urinary tract infection, which have shown hydrophilic properties and a great negative charge. However, the Sh. sonnei isolates were similar to E. coli strains belonging to certain serogroups which have been grown from patients with dysentery-like diseases. The results indicate that physico-chemical surface properties are related among enterobacteria belonging to different genera which have been grown from similar types of infections.