Difference between revisions of "Part:BBa K2978100"

Revision as of 23:35, 21 October 2019

Auto Inducer Protein for QS in Clostridioides difficile

This composite part was constructed to reproduce the Quorum Sensing signaling of C. difficile. It´s mechanisms is based on the Lubkowicz, et al., (2018) assays who reproduces the QS signaling from S. aureus.
Naturally, in C. difficile AgrD protein is code in higher expression levels when conditions are favorable for the pathogen. This peptide is modified and transport to the medium by the transmembrane AgrB protein, such modification results in the auto inducer protein (AIP) that recreates an infection/colonization induction in the bacteria.
AIP is sensing by the AgrC membrane protein, which phosphorylate AgrA protein when AIP is detected in the outsider of the bacteria. Once two AgrA protein are phosphorylated creates a dimer protein, and this joining form a DNA binding domain, still unknows in C. difficile, but well reported in S. aureus.
Both, AgrD and AgrB, have a pLac promoter with the objective to produce AIP when [http://openwetware.org/wiki/IPTG IPTG] is applied. Also, a GFP reporter is code polycistronically after the AgrD peptide, as a way to indirectly quantify the AIP. Is important to note that nickel affinity chromatography isn't used for this protein considering the insoluble properties of the peptide reported in literature, and the possible interference of a his tag during the process of AgrD by AgrB.

Protein Extraction

After induction, proteins were extracted and analyzed on a SDS-PAGE to see where is the AIP located. https://parts.igem.org/wiki/index.php?title=Part:BBa_K2978100&action=edit&section=1

Sequence and Features