The ultrastructure of the cellulolytic bacterium Cellvibrio fulvus

Thin sections of the cellulolytic bacterium Cellvibrio fulvus were investigated before and after treatment with polymyxin B and Triton X-100. The Gram-negative vibrio appeared to have no separate stained g2 layer between the L and C membranes. Cells lysed after treatment with polymyxin or swelled in the presence of 5% sucrose. Blebs were formed from the L membrane, and the inner structure of the cells changed. Triton X-100 lysed cells even in the presence of 20% sucrose. The flagellum disappeared before lysis; one of the membranes was dissolved; and no organized inner structure could be seen.