Zinc-dependent substrate-level phosphorylation powers Salmonella growth under nitrosative stress of the innate host response
Fig 7
Model for zinc and energy metabolism in the antinitrosative defenses of Salmonella.
ATP can be generated by substrate-level phosphorylation in glycolysis and acetate fermentation or oxidative phosphorylation in the electron transport chain. Nitric oxide (NO) produced by iNOS preferentially targets oxidative phosphorylation, and thus most ATP used for growth under nitrosative stress is derived from substrate-level phosphorylation. Zn2+ acquired through the ABC-type high affinity zinc transport system ZnuABC plays a critical role to the antinitrosative defenses of intracellular Salmonella by enabling fructose bisphosphate aldolase enzymatic activity in glycolysis. The utilization of zinc in multiple cellular processes also adds to the antinitrosative defenses of Salmonella.