Reconstitution of the Biochemical Activities of the AttJ Repressor and the AttK, AttL, and AttM Catabolic Enzymes of Agrobacterium tumefaciens

The attKLM operon encodes a lactonase (AttM) that hydrolyzes acylhomoserine lactone autoinducers, as well as two putative dehydrogenases (AttK and AttL). Here we show that AttK, AttL, and AttM collectively covert gamma-butyrolactone to succinate. Two metabolic intermediates, gamma-hydroxybutyrate and succinic semialdehyde, inactivated the AttJ repressor in vitro and induced attKLM transcription in vivo.