amprA complex link exists between cell-wall recycling/repair and the manifestation of resistance to β-lactam antibiotics in many Enterobacteriaceae and Pseudomonas aeruginosa. This process is mediated by specific cell-wall-derived muropeptide products. These muropeptides are internalized into the cytoplasm and bind to the transcriptional regulator AmpR, which controls the cytoplasmic events that lead to expression of β-lactamase, an antibiotic-resistance determinant. By a combination of X-ray crystallography, mass spectrometry and molecular dynamics techniques we have characterized the effector-binding domain (EBD) of AmpR. Our results provide insights on the muropeptides triggering antibiotics resistance and revises the dogma in the field.
This is part of a collaborative effort between the IQFR and the Univ. of Notre Dame (Indiana, USA).

Dik, D.A.; Domínguez-Gil, T.; Lee, M.; Hesek, D.; Byun, B.; Fishovitz, J.; Boggess, B.; Hellman, L.M.; Fisher, J. F.; Hermoso, J.A.; Mobashery, S. “Muropeptide Binding and the X-Ray Structure of the Effector Domain of the Transcriptional Regulator AmpR of Pseudomonas aeruginosa”. J. Am. Chem. Soc. (2017).