title: New peptides with metal binding abilities and their use as drug carriers.
abstract: Many new designed molecules that target efficiently in vitro bacterial metalloproteases were completely inactive in cellulo against Gram negative bacteria. Their activities were limited by the severe restriction of the penetration/diffusion rate through the outer membrane barrier. To bypass this limitation, we have assayed the strategy of metallodrugs, to improve the delivery of hydroxamic acid inhibitors to peptide deformylase. In this metal-chaperone, to facilitate bacterial uptake, the ancillary ligand tris(2-pyridylmethyl)amine (TPA) or di(picolyl)amine (DPA) was functionalized by a tetrapeptide analogue of antimicrobial peptide, RWRW(OBn) (AA08 with TPA) and/or an efflux pump modulator PAβN (AA09 with TPA and AA27 with DPA). We prepared Co(III), Zn(II), and Cu(II) metallodrugs. Using a fluorescent hydroxamic acid, we showed that, in contrast to Cu(II) metallodrugs, Co(III) metallodrugs were stable in the Mueller Hinton (MH) broth during the time required for bacterial assays. The antibacterial activities were determined against E. coli strain wild-type (AG100) and E. coli strain deleted from acrAB efflux pump (AG100A). While none of the PDFinhs used in this study (SMP289 with an indole scaffold, AT015 and AT019 built on a 1,2,4-oxadiazole scaffold) displayed activity higher than 128 μM, all the metallodrugs were active with MICs around 8 μM both against AG100 and AG100A. However, compared to the activities of equimolar combinations of PDFinhs and the free chelating peptides (AA08, AA09, or AA27), they showed similar activities. A synergistic association between AT019 and AA08 or AA09 was determined using the fractional inhibitory concentration with AG100 and AG100A. Combinations of peptides lacking the chelating group with PDFinhs were inefficient. LC-MS analyses showed that the chelating peptides bind Zn(II) cation when incubated in MH broth. These results support the in situ formation of a zinc metallodrug, but we failed to detect it by LC-MS in MH. Nevertheless, this chelating peptides metalated with zinc act as permeabilizers which are more efficient than PAβN to facilitate the uptake of PDFinhs by Gram(-) bacteria.
authors.affiliation: UMR8601, LCBPT, CNRS Université Paris Descartes, PRES Paris Cité , 45 rue des Sts Pères 75270 Paris Cedex 06, France.
authors.forename: Anas
authors.initials: A
authors.lastname: Allam
authors.forename: Laure
authors.initials: L
authors.lastname: Maigre
authors.forename: Mickael
authors.initials: M
authors.lastname: Alimi
authors.forename: Rodolphe
authors.initials: R
authors.lastname: Alves de Sousa
authors.forename: Assia
authors.initials: A
authors.lastname: Hessani
authors.forename: Erwan
authors.initials: E
authors.lastname: Galardon
authors.forename: Jean-Marie
authors.initials: JM
authors.lastname: Pagès
authors.forename: Isabelle
authors.initials: I
authors.lastname: Artaud
mesh_terms: D000581:Amidohydrolases / Q000037:antagonists & inhibitors / Q000378:metabolism; D000900:Anti-Bacterial Agents / Q000737:chemistry* / Q000494:pharmacology; D056831:Coordination Complexes / Q000737:chemistry* / Q000494:pharmacology; D004337:Drug Carriers / Q000737:chemistry*; D004926:Escherichia coli / Q000187:drug effects* / Q000201:enzymology; D004927:Escherichia coli Infections / Q000188:drug therapy; D006801:Humans; D008826:Microbial Sensitivity Tests; D010455:Peptides / Q000737:chemistry* / Q000494:pharmacology; D011725:Pyridines / Q000737:chemistry / Q000494:pharmacology
chemical_list: D000900:Anti-Bacterial Agents; D056831:Coordination Complexes; D004337:Drug Carriers; D010455:Peptides; D011725:Pyridines; C431843:tris(2-pyridylmethyl)amine; D000581:Amidohydrolases; C084507:peptide deformylase