DEVELOPMENT OF MARKERS FOR PRODUCT FORMATION AND CELL-CYCLE IN BATCH CULTIVATION OF CLOSTRIDIUM-ACETOBUTYLICUM ATCC-824

Experiments were performed to identify relationships between morpholog ical and physiological events during batch fermentation of Clostridium acetobutylicum ATCC 824. Differing fermentation conditions were obtai ned by manipulation of the culture pH value during the process. The ba cterium showed marked changes in morphology during its cultivation, si milar to those previously observed for other strains. However, althoug h the acidogenic phase was characterized by the presence of rod-shaped cells, and the solventogenic phase by clostridial forms, there was no simple relationship between the proportion of clostridial forms prese nt and the ratio of solvents to acids. Nevertheless, the shift from ac idogenesis to solventogenesis was always coincident with the presence of some clostridial forms and with the accumulation of granulose withi n the cells. In addition, the ''solvent shift'' was associated with ma jor changes in the cellular protein pattern, as analysed by sodium dod ecyl sulphate/polyacrylamide gel electrophoresis. Hence, the potential solventogenic ability of any particular culture may be recognised by its morphological appearance and/or its cellular protein pattern.