Studies on carbohydrate metabolism in Bacillus sphaericus 1593

Bacillus sphaericus 1593 was found to grow poorly on glucose when provided as sole carbon source. However, growth was significantly much higher when acetate was provided as the carbon source, as compared to glucose. The activities of aconitase, isocitrate dehydrogenase, glucose-6-phosphate dehydrogenase and isocitrate lyase were detectable which suggests the operation of TCA cycle, hexose monophosphate pathway and glyoxylate by pass. Only one form of isocitrate dehydrogenase and two forms of glucose-6-phosphate dehydrogenase were observed by activity staining. Further studies were substantiated by low respiration rate observed, when variety of intermediates of biochemical pathways were checked. Some metabolites, like 2-oxoglutarate, pyruvate, oxaloacetate and malate showed inhibitory effect on isocitrate lyase activity.