title: A Novel Depsipeptide Produced by Paenibacillus alvei 32 Isolated from a Cystic fibrosis Patient.
abstract: The important viscosity of the respiratory tract mucus of Cystic fibrosis (CF) patients impairs the mucociliary transport system and allows the growth of numerous micro-organisms. Among them, Pseudomonas aeruginosa and Staphylococcus aureus are known to be responsible for pulmonary infections. We imagined that CF microflora could also harbour micro-organisms naturally equipped to compete with these pathogens. A method was developed to recover these antibiotic-producing strains within 20 CF sputum. Using this approach, we have isolated an unusual Gram-positive bacterium identified as Paenibacillus alvei by Api galleries and 16S rRNA gene sequence analysis. This strain has inhibited the growth of P. aeruginosa, S. aureus and Klebsiella pneumoniae, in co-cultures. A liquid mineral medium named MODT50 was designed and optimised for the production and the recovery of the antimicrobial compounds. The supernatant has inhibited the growth of all Gram-positive strains tested, even Methicillin-resistant S. aureus. One antimicrobial compound with a peptide structure (mainly active against S. aureus, Micrococcus luteus, and Pseudomonas stutzeri) has been purified and characterised by liquid chromatography-mass spectrometry. The new active molecule (m/z 786.6) named depsipeptide L possesses a 15-guanidino-3-hydroxypentadecanoic acid side chain (m/z 298) linked on a cyclic part of four amino acids residues (Ser, two Leu/Ile, Arg). This work reports for the first time the production of such a molecule by a P. alvei strain in a mineral medium. The CF lung microflora might represent a valuable source for the discovery of new antimicrobial-producing strains.
authors.affiliation: Laboratoire Littoral Environnement et Sociétés, LIENSs, Université de La Rochelle, UMR 7266, CNRS, Avenue Michel Crépeau, 17042, Rochelle Cedex 1, France. romain.chevrot01@univ-lr.fr.
authors.forename: Romain
authors.initials: R
authors.lastname: Chevrot
authors.affiliation: Laboratoire Littoral Environnement et Sociétés, LIENSs, Université de La Rochelle, UMR 7266, CNRS, Avenue Michel Crépeau, 17042, Rochelle Cedex 1, France. sandrine.didelot@univ-lr.fr.
authors.forename: Sandrine
authors.initials: S
authors.lastname: Didelot
authors.affiliation: Faculteit Farmaceutische Wetenschappen, Laboratorium voor Farmaceutische Analyse, O&N 2, Herestraat 49, PB 923, 3000, Leuven, Belgium.
authors.forename: Larissa
authors.initials: L
authors.lastname: Van den Bossche
authors.affiliation: Laboratoire Littoral Environnement et Sociétés, LIENSs, Université de La Rochelle, UMR 7266, CNRS, Avenue Michel Crépeau, 17042, Rochelle Cedex 1, France.
authors.forename: Fatoumata
authors.initials: F
authors.lastname: Tambadou
authors.affiliation: Laboratoire ProBioGem, Université des Sciences et Technologies de Lille, 59655, Villeneuve d'Ascq Cedex, France.
authors.forename: Thibault
authors.initials: T
authors.lastname: Caradec
authors.affiliation: Laboratoire Littoral Environnement et Sociétés, LIENSs, Université de La Rochelle, UMR 7266, CNRS, Avenue Michel Crépeau, 17042, Rochelle Cedex 1, France.
authors.forename: Pierre
authors.initials: P
authors.lastname: Marchand
authors.affiliation: Laboratoire Littoral Environnement et Sociétés, LIENSs, Université de La Rochelle, UMR 7266, CNRS, Avenue Michel Crépeau, 17042, Rochelle Cedex 1, France.
authors.forename: Esther
authors.initials: E
authors.lastname: Izquierdo
authors.affiliation: Laboratoire Littoral Environnement et Sociétés, LIENSs, Université de La Rochelle, UMR 7266, CNRS, Avenue Michel Crépeau, 17042, Rochelle Cedex 1, France.
authors.forename: Valérie
authors.initials: V
authors.lastname: Sopéna
authors.affiliation: Laboratoire de Thérapeutique Clinique & Expérimentale, Faculté de Médecine, UPRES EA 3826, 1 rue Gaston Veil, 44035, Nantes, France.
authors.forename: Jocelyne
authors.initials: J
authors.lastname: Caillon
authors.affiliation: Laboratoire Littoral Environnement et Sociétés, LIENSs, Université de La Rochelle, UMR 7266, CNRS, Avenue Michel Crépeau, 17042, Rochelle Cedex 1, France.
authors.forename: Cyrille
authors.initials: C
authors.lastname: Barthélémy
authors.affiliation: Faculteit Farmaceutische Wetenschappen, Laboratorium voor Farmaceutische Analyse, O&N 2, Herestraat 49, PB 923, 3000, Leuven, Belgium.
authors.forename: Ann
authors.initials: A
authors.lastname: Van Schepdael
authors.affiliation: Faculteit Farmaceutische Wetenschappen, Laboratorium voor Farmaceutische Analyse, O&N 2, Herestraat 49, PB 923, 3000, Leuven, Belgium.
authors.forename: Jos
authors.initials: J
authors.lastname: Hoogmartens
authors.affiliation: Laboratoire Littoral Environnement et Sociétés, LIENSs, Université de La Rochelle, UMR 7266, CNRS, Avenue Michel Crépeau, 17042, Rochelle Cedex 1, France.
authors.forename: Eric
authors.initials: E
authors.lastname: Rosenfeld
keywords: Antimicrobial-peptide; Cystic fibrosis; Depsipeptide; Fusaricidin; Paenibacillus alvei