Difference between revisions of "Part:BBa K143033"

Revision as of 14:09, 17 September 2008

LacI (Lva^-, N-terminal deletion) regulatory protein

LacI is a regulatory protein responsible for the repression of many catabolite genes. Transcription is regulated by proteins which bind operator sequences around the transcription start site. These proteins can positively affect transcription (activators) or negatively affect transcription (repressors). Many repressor proteins are inactivated by addition of an inducer, such as IPTG or certain sugars.

LacI is the regulator protein for the lactose operon in E.coli and the hyper-spank promoter of B. subtilis#1(BBaK143015) and is responsible for ensuring there is no expression through these promoters in the absence of lactose (or IPTG). LacI is not endogenous to B. subtilis so LacI will need to be expressed in the host in order for the hyper-spank promoter to be regulated. In the presence of IPTG or lactose, the LacI tetramer is unable to bind DNA and so transcription resumes.

This version of LacI lacks a Lva degradation tag and has a small(3 amino acid) N-terminal deletion relative to the current registry LacI (BBa_C0012) and acted as an input adaptor for a Polymerases per second (POPS) output

Sequence and Features