[Ultrastructural organization of trichomes of a new group of multicellular gram-negative bacteria].

Peculiar trichome multicellular gram-negative bacteria were found in several types of soil, and were isolated as pure cultures. The bacteria are characterized by the following properties: (a) the presence of large regions of the periplasm, 200-300 nm thick, in the cells, the volume of the periplasm being greater than that of the cytoplasm; (b) a peculiar structure of multicellular trichomes in which the cells are surrounded by a common cell wall and a common periplasmic space; (c) a specific structure of trichome septa formed by membrane leaves and including no material of the cell wall; (d) the ability of protoplasts to divide within the trichome cell wall; (e) the ability to grow under anaerobic conditions. Therefore, these organisms belong to a new group of trichome multicellular bacteria.