GraR

Usage and Biology

GraR is known for its role in β-lactam resistance by upregulating cell wall biosynthesis genes, altering cell wall composition, and increasing expression of ABC-transporters (El-Halfawy et al., 2020; Yang et al., 2012; Meehl et al., 2007). The GraSR system is a two-component regulatory system that controls the expression of many genes involved in stress response, cell wall metabolism and virulence pathways in Staphylococcus aureus (Falord et al., 2011).

Accordingly, GraR functions as a transcription factor and our cell-based antiobiotics sensor utilises it as such by aiming for its PknB-dependent phyosphorylation (K5317013).

Cloning

Theoretical Part Design

This part was codon optimised for human cell lines and was synthesised by Eurofins.

Sequence and Features

Assembly Compatibility:

10
INCOMPATIBLE WITH RFC[10]
Illegal XbaI site found at 235
12
COMPATIBLE WITH RFC[12]
21
COMPATIBLE WITH RFC[21]
23
INCOMPATIBLE WITH RFC[23]
Illegal XbaI site found at 235
25
INCOMPATIBLE WITH RFC[25]
Illegal XbaI site found at 235
1000
COMPATIBLE WITH RFC[1000]

Characterization

The graR functionality was analyzed by composing a gene cassette where its placed downstream of the constitutuve CMV promoter and fused with the reporter gene mRuby2 to assess by incubation with ß-lactam antibiotics the ccpA localization based on the fluorescent signal. Please visit the K5317020 registry entry to view the results.

References

El-Halfawy, O. M., Czarny, T. L., Flannagan, R. S., Day, J., Bozelli, J. C., Kuiack, R. C., Salim, A., Eckert, P., Epand, R. M., McGavin, M. J., Organ, M. G., Heinrichs, D. E., & Brown, E. D. (2020). Discovery of an antivirulence compound that reverses β-lactam resistance in MRSA. Nature Chemical Biology, 16(2), 143–149. https://doi.org/10.1038/s41589-019-0401-8

Falord, M., Mäder, U., Hiron, A., Débarbouillé, M., & Msadek, T. (2011). Investigation of the Staphylococcus aureus GraSR Regulon Reveals Novel Links to Virulence, Stress Response and Cell Wall Signal Transduction Pathways. PLoS ONE, 6(7), e21323. https://doi.org/10.1371/journal.pone.0021323

Meehl, M., Herbert, S., Götz, F., & Cheung, A. (2007). Interaction of the GraRS Two-Component System with the VraFG ABC Transporter To Support Vancomycin-Intermediate Resistance in Staphylococcus aureus. Antimicrobial Agents and Chemotherapy , 51(8), 2679–2689. https://doi.org/10.1128/AAC.00209-07