The seroresistance of enterobacteria isolated from different sources

395 representatives of the family Enterobacteriaceae, isolated from household and drinking water, from healthy and sick persons, were used as an example to demonstrate that their seroresistance was greatly connected with the type of the source from which these bacteria had been isolated. Experiments showed the phenotypic conversion of Escherichia coli towards an increase in their seroresistance on contact with human blood serum. The study revealed the pleiotropic effect produced by the action of serum on a number of other properties, responsible for survival in a macroorganism (anticomplement and antilysozyme activities, adhesive capacity and hydrophobic properties of the outer surface).