title: Design and expression of peptides with antimicrobial activity against Salmonella typhimurium.
abstract: We showed previously that insertion of Synechocystis Δ12-desaturase in salmonella's membrane alters membrane physical state (MPS), followed by the expression of stress genes causing inability to survive within murine macrophages (MΦ). Recently, we showed that expression of one membrane lipid domain (MLD) of Δ12-desaturase (ORF200) interferes with salmonella MPS, causing loss of virulence in mice and immunoprotection. Here, we postulate that an α-antimicrobial peptide (α-AMP) intercalates within membrane lipids, and depending on its amino acid sequence, it does so within specific key sensors of MLD. In this study, we choose as target for a putative synthetic AMP, PhoP/PhoQ, a sensor that responds to low Mg2+concentration. We synthesised a modified DNA fragment coding for an amino acid sequence (NUF) similar to that fragment and expressed it in salmonella typhimurium. We showed that the pattern of gene expression controlled by PhoP/PhoQ highlights dysregulation of pathways involving phospholipids biosynthesis, stress proteins and genes coding for antigens. RNA-Seq of strain expressing ORF200 showed that the pattern of those genes is also altered here. Accumulation of NUF conferred temporary immunoprotection. This represents a powerful procedure to address synthetic α-AMPs to a specific MLD generating live non-virulent bacterial strains.
authors.affiliation: Department of Pharmacy, University of Salerno, Fisciano, (SA), Italy.
authors.forename: Amalia
authors.initials: A
authors.lastname: Porta
authors.affiliation: Department of Pharmacy, University of Salerno, Fisciano, (SA), Italy.|PhD Program in Drug Discovery and Development, University of Salerno, Fisciano, SA, Italy.
authors.forename: Anna Maria
authors.initials: AM
authors.lastname: Petrone
authors.affiliation: Department of Pharmacy, University of Salerno, Fisciano, (SA), Italy.
authors.forename: Silvana
authors.initials: S
authors.lastname: Morello
authors.affiliation: Department of Pharmacy, University of Salerno, Fisciano, (SA), Italy.
authors.forename: Ilaria
authors.initials: I
authors.lastname: Granata
authors.affiliation: Laboratory of Molecular Medicine and Genomics, Department of Medicine and Surgery, University of Salerno, Baronissi, SA, Italy.
authors.forename: Francesca
authors.initials: F
authors.lastname: Rizzo
authors.affiliation: Laboratory of Molecular Medicine and Genomics, Department of Medicine and Surgery, University of Salerno, Baronissi, SA, Italy.
authors.forename: Domenico
authors.initials: D
authors.lastname: Memoli
authors.affiliation: Laboratory of Molecular Medicine and Genomics, Department of Medicine and Surgery, University of Salerno, Baronissi, SA, Italy.
authors.forename: Alessandro
authors.identifier: 0000-0003-0455-2083
authors.initials: A
authors.lastname: Weisz
authors.affiliation: Department of Pharmacy, University of Salerno, Fisciano, (SA), Italy.
authors.forename: Bruno
authors.initials: B
authors.lastname: Maresca
mesh_terms: D000818:Animals; D000890:Anti-Infective Agents / Q000378:metabolism*; D001426:Bacterial Proteins / Q000378:metabolism; D015870:Gene Expression; D015964:Gene Expression Regulation, Bacterial; D008264:Macrophages / Q000276:immunology / Q000382:microbiology; D008810:Mice, Inbred C57BL; D050296:Microbial Viability; D010455:Peptides / Q000235:genetics / Q000378:metabolism*; D012481:Salmonella Infections, Animal / Q000276:immunology / Q000382:microbiology; D012486:Salmonella typhimurium / Q000235:genetics / Q000276:immunology / Q000378:metabolism / Q000502:physiology*; D014774:Virulence
chemical_list: D000890:Anti-Infective Agents; D001426:Bacterial Proteins; D010455:Peptides