Abnormal septation and inhibition of sporulation by accumulation of L- -glycerophosphate in Bacillus subtilis mutants

Abstract

Accumulation of l-alpha-glycerophosphate, in cells of Bacillus subtilis mutants lacking the nicotinamide adenine dinucleotide-independent glycerophosphate dehydrogenase activity, suppresses both growth and sporulation. After growth has stopped, the cells slowly develop one and later more asymmetric septa that are thicker than normal prespore septa and apparently contain too much cell wall material to allow further membrane development into forespores or spores. l-Malate prevents accumulation of glycerophosphate and restores sporulation of the mutant. Glucose or gluconate cannot resotre sporulation, because they still effect glycerophosphate accumulation via de novo synthesis. If that accumulation is blocked in a double mutant, which is unable to make glycerophosphate from or to metabolize it into Embden-Meyerhof compounds, then nonsuppressing amounts of glucose or gluconate can restore sporulation.