Adenosine thiamine triphosphate, a new signal synthesized in response to specific forms of cellular stress in Escherichia coli

Thiamine, also known as vitamin B1, and its different phosphorylated derivates are found in all known organisms. The main form of the vitamin is the coenzyme thiamine diphosphate (ThDP). Thiamine triphosphate (ThTP) is also found in low amounts in all organisms studied from bacteria to mammals. In E. coli ThTP accumulation is linked to amino acid starvation and the presence of a suitable carbon source. Recently a new thiamine derivative, adenosine thiamine triphosphate (AThTP) or thiaminylated ATP was discovered in our laboratory. AThTP is accumulated in E. coli during carbon starvation. When the cells are grown under optimal conditions (rich medium containing amino acids) neither ThTP nor AThTP is present in significant amounts. The synthesis of both compounds is inhibited by amino acids. In E. coli, AThTP accumulates in response to two different conditions of metabolic stress: lack of energy substrates (or inhibition of their metabolization) and uncoupled pyruvate oxidation.