4GCP: Crystal Structure Of E. Coli Ompf Porin In Complex With Ampicillin

The structure of OmpF porin in complex with three common antibiotics (zwitterionic ampicillin, anionic ertapenem, and di-anionic carbenicillin) was determined using X-ray crystallography. The three antibiotics are found to bind within the extracellular and periplasmic pore vestibules, away from the narrow OmpF constriction zone. Using the X-ray structures as a starting point, nonequilibrium molecular dynamics simulations with an applied membrane voltage show that ionic current through the OmpF channel is blocked with bound ampicillin, but not with bound carbenicillin. The susceptibility of Escherichia coli expressing OmpF mutants to ampicillin and carbenicillin was also experimentally characterized using microbiologic assays. These results show that general diffusion by OmpF porins allows for transfer of molecules with varied charged states and give insights into the design of more efficient antibiotics. A better understanding of this mechanism will shed light on nature's way of devising channels able to enhance the transport of molecules through membranes.
PDB ID: 4GCPDownload
MMDB ID: 105953
PDB Deposition Date: 2012/7/30
Updated in MMDB: 2012/12
Experimental Method:
x-ray diffraction
Resolution: 1.98  Å
Source Organism:
Similar Structures:
Biological Unit for 4GCP: trimeric; determined by author and by software (PISA)
Molecular Components in 4GCP
Label Count Molecule
Proteins (3 molecules)
Outer Membrane Protein F(Gene symbol: ompF)
Molecule annotation
Chemicals (3 molecules)
* Click molecule labels to explore molecular sequence information.

Citing MMDB