SPECIFIC PHOTOAFFINITY-LABELING OF A FERRIPYOVERDIN OUTER-MEMBRANE RECEPTOR OF PSEUDOMONAS-AERUGINOSA

In order to identify and characterize the receptors involved in pyover din-mediated iron transport in Pseudomonas aeruginosa ATCC 15692, a ph otoactivatable siderophore has been synthesized, In the dark, this pro be is stable and is able to promote iron transport at the same rate as the native pyoverdin. Under irradiation at 312 nm, the molecule is ph otodecomposed and a clear inhibition of the iron transport is observed , With the radioactive form of this photoactivatable probe, we were ab le to visualize on a SDS-PAGE gel a labelled protein of approximately 90 kDa molecular mass, which is very likely the FpvA receptor or a yet unknown pyoverdin receptor.