Physiologically relevant small phosphodonors link metabolism to signal transduction

Recent reports support the long-standing hypothesis that acetyl phosphate, a physiologically relevant small molecule, can serve as a phosphoryl donor to a subset of two-component response regulators that regulate diverse cellular processes. Since acetyl phosphate is a central metabolite, this ability would link nutritional status to global signaling. This review will first introduce acetyl phosphate and its pathway. It will then summarize the most compelling evidence supporting the hypothesis and list predicted properties of an acetyl phosphate-sensitive pathway. Next, it will describe emerging evidence that acetyl phosphate and/or its pathway can influence diverse cellular processes across a broad spectrum of bacteria. Finally, the review will explore the possibility that other metabolites can function in a capacity similar to acetyl phosphate.