Difference between revisions of "Part:BBa K143036"

Revision as of 11:19, 18 September 2008

Xylose operon regulatory protein

Transcription is regulated by proteins which bind operator sequences around the transcription start site. These proteins can affect transcription positively (activators) or negatively (repressors). Many repressor proteins can be inactivated by addition of an inducer, such as xylose.

XylR is the regulatory protein of the Xylose operon in B. subtilis#1 and is responsible for ensuring the xylose metabolism proteins are not expressed in the absence of xylose . Though XylR is endogenous to B. subtilis, XylR should be over-expressed to minimise the leakage of xylose inducible promoters. In the presence of xylose, the XylR multimer is unable to bind DNA and repression of transcription is released.

It must be noted that in all B. subtilis strains with a functional endoegouns xylose operon the xylose inducer will gradually be metabolised by the host.

XylR can be used in conjunction with the Xylose operon promoter (BBa_K143014), where the XylR will act as a reciever for an xylose input to result in an Polymerases per second (PoPS) output.

Sequence and Features