Structure of bacteriocin AS-48: from soluble state to membrane bound state.
The bacteriocin AS-48 is a membrane-interacting peptide, which displays a broad anti-microbial spectrum against Gram-positive and Gram-negative bacteria. The NMR structure of AS-48 at pH 3 has been solved. The analysis of this structure suggests that the mechanism of AS-48 anti-bacterial activity involves the accumulation of positively charged molecules at the membrane surface leading to a disruption of the membrane potential. Here, we report the high-resolution crystal structure of AS-48 and sedimentation equilibrium experiments showing that this bacteriocin is able to adopt different oligomeric structures according to the physicochemical environment. The analysis of these structures suggests a mechanism for molecular function of AS-48 involving a transition from a water-soluble form to a membrane-bound state upon membrane binding.
Sánchez-Barrena
M J
MJ
Grupo de Cristalografía Macromolecular y Biología Estructural, Instituto de Química Física Rocasolano, Consejo Superior de Investigaciones Científicas, Serrano 119, E-28006, Madrid, Spain.
Martínez-Ripoll
M
M
Gálvez
A
A
Valdivia
E
E
Maqueda
M
M
Cruz
V
V
Albert
A
A
D001426:Bacterial Proteins; D002462:Cell Membrane / Q000378:metabolism; D018360:Crystallography, X-Ray; D006094:Gram-Positive Bacteria / Q000737:chemistry* / Q000235:genetics; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D015394:Molecular Structure; D010455:Peptides / Q000737:chemistry* / Q000378:metabolism; D011487:Protein Conformation; D014867:Water / Q000737:chemistry
D001426:Bacterial Proteins; D010455:Peptides; D014867:Water; C051034:BacA protein, Enterococcus faecalis