[An electron microscopic study of the intercellular contact of a vaccinal strain of Francisella tularensis with gram-negative and gram-positive bacteria].

The use of transmission electron microscopy (the negative contrast and ultrathin section techniques) has made it possible to show that F. tularensis vaccine strain is capable, under normal conditions and in mixtures with other gram-negative and gram-positive bacteria, of forming cell aggregations with close contacts between cells, this contact being probably irreversible. The ultrastructure of bacteria taking part in the formation of intercellular contacts remains intact.