From 2007.igem.org

According to the in vitro cross-binding data reported by Kalodimos et al.[1], We used [http://partsregistry.org/Part:BBa_I732100|LacI] and [http://partsregistry.org/Part:BBa_I732101|LRLa] as the upstream input signals in the first version co-repression test-bench, and used O11 (the symmetric operator of [http://partsregistry.org/Part:BBa_I732100|LacI]) and O22(the symmetric operator of [http://partsregistry.org/Part:BBa_I732101|LRLa]) to construct logic promoters such as [http://partsregistry.org/Part:BBa_I732352|BBa_I732352]. But unfortunately, experimental data show that these two repressor can bind to the relative operator of each other in vivo. All measurements of co-repression based-on these two repressors are abandoned. The combination of [http://partsregistry.org/Part:BBa_I732100|LacI] and [http://partsregistry.org/partsdb/view.cgi?part_id=9753|ARL2A0203] are replaced with [http://partsregistry.org/partsdb/view.cgi?part_id=9758|ARL4A0604] in the later experiments.