Project Details
Projekt
Antibiotic efflux transporters in Acinetobacter baumannii
Applicant
Professor Dr. Klaas Martinus Pos
Subject Area
Metabolism, Biochemistry and Genetics of Microorganisms
Term
from 2014 to 2023
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 258351992
The first line of defense in the antibiotic stress adaptation strategy of Acinetobacter baumannii is the expression of antibiotic efflux pump genes, resulting in the equipment of the inner and outer membrane with transporters and channels which catalyze the concerted efflux of toxic compounds. The combined effort of secondary active efflux pumps from the major facilitator (MF), resistance nodulation and cell division (RND), small multidrug resistance (SMR) and multidrug and toxic compound extrusion (MATE) (super)families leads to the observed resistance against multiple drugs including various classes of antibiotics, detergents and dyes. We aim to structurally and functionally characterize three selected antibiotic efflux transporters from A. baumannii, the small multidrug transporter AbeS, and two major facilitator superfamily members CraA and TetA(G). These transporters have been purified and will be characterized on their substrate specificity using isothermal titration calorimetry, scintillation proximity assays and microscale thermophoresis and on their transport properties and energetics in a proteoliposomal system. Furthermore, we will subject the purified proteins to vapor-diffusion and lipidic cubic phase crystallization and aim for structural elucidation via x-ray crystallography. The role of these transporters and their interdependence upon antibiotic stress will be addressed using combinatorial A. baumannii knock-out mutants complemented by the inactive mutant genes using functional assays and efflux pump transcriptome analysis.
DFG Programme
Research Units
