qMaLioffG is a genetically encoded fluorescence lifetime-based ATP sensor that can be used for quantitative imaging of intracellular ATP. It consists of an ATP-binding sequence (derived from the F[[0]]F[[1]]-ATP synthase ε subunit encoded by the Bacillus subtilis atpC gene) which has been inserted, flanked by short peptide linkers, into the Citrine fluorescent protein. Upon binding ATP, a change in conformation of the ATP-binding sequence results in a decrease in fluorescence (FBrf0263856).