The Pseudomonas aeruginosa membranes: A target for a new amphiphilic aminoglycoside derivative?

in Biochimica et biophysica acta (2011)

Aminoglycosides are among the most potent antimicrobials to eradicate Pseudomonas aeruginosa. However, the emergence of resistance has clearly led to a shortage of treatment options, especially for ... [more ▼]

Aminoglycosides are among the most potent antimicrobials to eradicate Pseudomonas aeruginosa. However, the emergence of resistance has clearly led to a shortage of treatment options, especially for critically ill patients. In the search for new antibiotics, we have synthesized derivatives of the small aminoglycoside, neamine. The amphiphilic aminoglycoside 3',4',6-tri-2-naphtylmethylene neamine (3',4',6-tri-2NM neamine) has appeared to be active against sensitive and resistant P. aeruginosa strains as well as Staphylococcus aureus strains (Baussanne et al., 2010). To understand the molecular mechanism involved, we determined the ability of 3',4',6-tri-2NM neamine to alter the protein synthesis and to interact with the bacterial membranes of P. aeruginosa or models mimicking these membranes. Using atomic force microscopy, we observed a decrease of P. aeruginosa cell thickness. In models of bacterial lipid membranes, we showed a lipid membrane permeabilization in agreement with the deep insertion of 3',4',6-tri-2NM neamine within lipid bilayer as predicted by modeling. This new amphiphilic aminoglycoside bound to lipopolysaccharides and induced P. aeruginosa membrane depolarization. All these effects were compared to those obtained with neamine, the disubstituted neamine derivative (3',6-di-2NM neamine), conventional aminoglycosides (neomycin B and gentamicin) as well as to compounds acting on lipid bilayers like colistin and chlorhexidine. All together, the data showed that naphthylmethyl neamine derivatives target the membrane of P. aeruginosa. This should offer promising prospects in the search for new antibacterials against drug- or biocide-resistant strains. [less ▲]

Pseudomonas putida BTP1 induces systemic accumulation of phytoalexins in cucumber associated with protection against Pythium root rot.

Conference (1999)

Pseudomonas putida BTP1 produced a new type of pyoverdine showing interacting properties and confirming the biogenesis of these compounds.

Poster (1993, November)

Pseudoscalar vertex and quark masses

in Nuclear Physics B Proceedings Supplement (2000), 83

Pseudospores in the late Ordovician of the Brabant Massif, Belgium: biological evolution and paleogeographical implications

Conference (1992)

PSF modeling of the XMM flight mirror modules

in Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series (1999, October 01)

In the frame of XMM testing, all the mirror modules have been illuminated by a vertical EUV collimated beam a the Centre Spatial de Liege. A mirror module consists in 58 co- focal and co-axial Wolter I ... [more ▼]

In the frame of XMM testing, all the mirror modules have been illuminated by a vertical EUV collimated beam a the Centre Spatial de Liege. A mirror module consists in 58 co- focal and co-axial Wolter I mirrors. Up to now the images obtained at CSL have been used to assess the Mirror Module optical performances in a flight representative configuration, and also to verify the impact of the thermal environmental and vibration test on the optical performance. Due to the highly complex design of the Mirror Modules, simulating XMM images in details is very difficult. The Point Spread Function of some of the mirror modules presents slight asymmetry. In the facility design study, it has been demonstrated that the diffraction impact at 58.4 nm is negligible with respect to the half energy width mirror module specification. Presently all the mirror modules are better than 165 arcsec. This paper presents first the diffraction contribution on the image. In a second step a point spread function is built by using the metrological mirror shell data. EUV images are then analyzed to evaluate the impact of the mirror interface structure integration process on the PSF. An analytical model of the measured EUV pSF is developed. The modelization technique is applied to simulate in-orbit image. Finally the different modelizations are evaluated and compared. [less ▲]

Psicologia de la educacion

Book published by Bello (2002)

Psicopedagogia

Book published by La Scuola (2000)

PSL : an ontology based language for the representation of multi-lingual urban permitting systems

in Proceedings of World Conference on Accelerating Excellence in The Built Environment (WCAEBE) (2006)

Psychanalyse au bord du néant

E-print/Working paper (2010)

Réflexion au sujet des liens entre la psychanalyse et l'écriture à partir du roman Flac du psychanalyste et romancier Serge André.