Modifications of surface properties in some enteropathogenic serogroups of Escherichia coli

Studies have been carried out on protein and fatty acid patterns present in the outer layers of E. coli strains which are considered pathogenic in relation to their serogroup. The patterns were related to surface properties of hydrophobicity of the same cells and to their resistance to phagocytosis. The results obtained demonstrate the presence in the pathogenic serogroups of a proteic band of high molecular weight as well as differences in the percentages of fatty acids with respect to the non-pathogenic serogroups. Furthermore, these serogroups are more resistant to phagocytosis; this resistance seems to be correlated to a greater surface hydrophilia of the pathogenic serogroups, leading to different relations of the lipidic and protein fraction of the outer layers.