High resolution studies of the Afa/Dr adhesin DraE and its interaction with chloramphenicol.
Pathogenic Escherichia coli expressing Afa/Dr adhesins are able to cause both urinary tract and diarrheal infections. The Afa/Dr adhesins confer adherence to epithelial cells via interactions with the human complement regulating protein, decay accelerating factor (DAF or CD55). Two of the Afa/Dr adhesions, AfaE-III and DraE, differ from each other by only three residues but are reported to have several different properties. One such difference is disruption of the interaction between DraE and CD55 by chloramphenicol, whereas binding of AfaE-III to CD55 is unaffected. Here we present a crystal structure of a strand-swapped trimer of wild type DraE. We also present a crystal structure of this trimer in complex with chloramphenicol, as well as NMR data supporting the binding position of chloramphenicol within the crystal. The crystal structure reveals the precise atomic basis for the sensitivity of DraE-CD55 binding to chloramphenicol and demonstrates that in contrast to other chloramphenicol-protein complexes, drug binding is mediated via recognition of the chlorine "tail" rather than via intercalation of the benzene rings into a hydrophobic pocket.
Laboratory of Molecular Biophysics, Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, United Kingdom.
David
D
Pettigrew
Kirstine L
KL
Anderson
Jason
J
Billington
Ernesto
E
Cota
Peter
P
Simpson
Petri
P
Urvil
Filip
F
Rabuzin
Pietro
P
Roversi
Bogdan
B
Nowicki
Laurence
L
du Merle
Chantal
C
Le Bouguénec
Stephen
S
Matthews
Susan M
SM
Lea
D018829:Adhesins, Bacterial / Q000737:chemistry* / Q000378:metabolism; D018830:Adhesins, Escherichia coli / Q000737:chemistry* / Q000378:metabolism; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001422:Bacterial Adhesion; D018958:CD55 Antigens / Q000737:chemistry; D002701:Chloramphenicol / Q000737:chemistry* / Q000378:metabolism / Q000494:pharmacology; D003001:Cloning, Molecular; D003165:Complement System Proteins; D018360:Crystallography, X-Ray; D029968:Escherichia coli Proteins / Q000737:chemistry* / Q000378:metabolism; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D011485:Protein Binding; D011487:Protein Conformation; D017433:Protein Structure, Secondary; D020349:Surface Plasmon Resonance; D014965:X-Rays
D018829:Adhesins, Bacterial; D018830:Adhesins, Escherichia coli; C108509:AfaE protein, E coli; D000900:Anti-Bacterial Agents; D018958:CD55 Antigens; C465563:DraE protein, E coli; D029968:Escherichia coli Proteins; D002701:Chloramphenicol; D003165:Complement System Proteins