lacI
crp
lacZ
lacY
lacA
crp
lacZ
L-Ara4n
D-Glc
cAMP
Lactin
cAMP
Operato
ABS
P
βG
LP
GOA
ρIT
Allolactose binds to the
repressor, inactivating it
and allowing transcription
cAMP binds to the
transcriptional regulator
CRP, allowing it to bind to
the activator binding site