Cell division in bacteria is driven by a cytoskeletal ring structure, the Z 
ring, composed of polymers of the tubulin-like protein FtsZ. Z-ring formation 
must be tightly regulated to ensure faithful cell division, and several 
mechanisms that influence the positioning and timing of Z-ring assembly have 
been described. Another important but as yet poorly understood aspect of cell 
division regulation is the need to coordinate division with cell growth and 
nutrient availability. In this study, we demonstrated for the first time that 
cell division is intimately linked to central carbon metabolism in the model 
Gram-positive bacterium Bacillus subtilis. We showed that a deletion of the gene 
encoding pyruvate kinase (pyk), which produces pyruvate in the final reaction of 
glycolysis, rescues the assembly defect of a temperature-sensitive ftsZ mutant 
and has significant effects on Z-ring formation in wild-type B. subtilis cells. 
Addition of exogenous pyruvate restores normal division in the absence of the 
pyruvate kinase enzyme, implicating pyruvate as a key metabolite in the 
coordination of bacterial growth and division. Our results support a model in 
which pyruvate levels are coupled to Z-ring assembly via an enzyme that actually 
metabolizes pyruvate, the E1α subunit of pyruvate dehydrogenase. We have shown 
that this protein localizes over the nucleoid in a pyruvate-dependent manner and 
may stimulate more efficient Z-ring formation at the cell center under 
nutrient-rich conditions, when cells must divide more frequently.
IMPORTANCE: How bacteria coordinate cell cycle processes with nutrient 
availability and growth is a fundamental yet unresolved question in 
microbiology. Recent breakthroughs have revealed that nutritional information 
can be transmitted directly from metabolic pathways to the cell cycle machinery 
and that this can serve as a mechanism for fine-tuning cell cycle processes in 
response to changes in environmental conditions. Here we identified a novel link 
between glycolysis and cell division in Bacillus subtilis. We showed that 
pyruvate, the final product of glycolysis, plays an important role in 
maintaining normal division. Nutrient-dependent changes in pyruvate levels 
affect the function of the cell division protein FtsZ, most likely by modifying 
the activity of an enzyme that metabolizes pyruvate, namely, pyruvate 
dehydrogenase E1α. Ultimately this system may help to coordinate bacterial 
division with nutritional conditions to ensure the survival of newborn cells.