[Electron microscopic study of the interaction of virulent and avirulent Shigella flexneri strains with the macrophages of murine peritoneal exudate].

The electron microscopic dynamic study of the interaction of S. flexneri virulent strain 2a and S. flexneri avirulent strain, genetically related to strain 2a and having the same antigenic structure, with peritoneal macrophages of CBA mice at an early period showed differences in the cytotoxic action of these strains.

The morphology and nucleotide composition of DNA of Citrobacter phages.

Citrobacter phages 38/37, 31/37, 40/1 and 8/5, isolated from lysogenic cultures, were concentrated and purified by 2 cycles of differential centrifugation. Electron microscopy of the phages has shown that their particles have similar morphology and that they relate to the morphological group A1. The heads of the phages are hexagonal, 50 +/- 2 nm in diameter.

[Antigenic structure of Salmonella L forms studied by an immunoferritin method].

The antigenic structure of the L-forms of salmonellae (S. typhimurium and S. typhi) in comparison with that of the initial bacterial cultures and revertant cultures was studied with the use of the immunoferritin method.

[Electron microscopic study of the interaction of Yersinia pseudotuberculosis with macrophages and HeLa cells].

The comparative electron-microscopic study of early stages of the interaction of Y. pseudotuberculosis virulent strain (No. 282) with "professional" (macrophages) and "nonprofessional" (HeLa cells) phagocytes has been carried out.

[Surface structure of the elementary bodies of Chlamydia].

The surface structure of chlamydial elementary bodies (strain PL-B577 causing enzootic abortion of ewes and strain CP-1 isolated from a patient with Reiter's syndrome), concentrated directly on the grid of an electron microscope, was studied by the method of negative staining. The surface of the cell wall of chlamydial elementary bodies in the preparations of crude cultures, not subjected to enzymatic purification, was formed by spherical subunits 4 nm in diameter. The surface of the cell wall of elementary bodies was found to have projections 10-20 nm long and 3-4 nm in diameter, as well as annular structures 15-22 nm in diameter in hexagonal arrangement, spaced at 45 nm and probably traversed by these projections.