title: A novel synthetic peptide from a tomato defensin exhibits antibacterial activities against Helicobacter pylori.
abstract: Defensins are a class of cysteine-rich proteins, which exert broad spectrum antimicrobial activity. In this work, we used a bioinformatic approach to identify putative defensins in the tomato genome. Fifteen proteins had a mature peptide that includes the well-conserved tetradisulfide array. We selected a representative member of the tomato defensin family; we chemically synthesized its γ-motif and tested its antimicrobial activity. Here, we demonstrate that the synthetic peptide exhibits potent antibacterial activity against Gram-positive bacteria, such as Staphylococcus aureus A170, Staphylococcus epidermidis, and Listeria monocytogenes, and Gram-negative bacteria, including Salmonella enterica serovar Paratyphi, Escherichia coli, and Helicobacter pylori. In addition, the synthetic peptide shows minimal (<5%) hemolytic activity and absence of cytotoxic effects against THP-1 cells. Finally, SolyC exerts an anti-inflammatory activity in vitro, as it downregulates the level of the proinflammatory cytokines TNF-α and IFN-γ.
authors.affiliation: University of Naples 'Federico II', School of Biotechnological Sciences, Department of Soil, Plant, Environmental and Animal Production Sciences, Via Università 100, 80055, Portici, Italy.
authors.forename: M M
authors.initials: MM
authors.lastname: Rigano
authors.forename: A
authors.initials: A
authors.lastname: Romanelli
authors.forename: A
authors.initials: A
authors.lastname: Fulgione
authors.forename: N
authors.initials: N
authors.lastname: Nocerino
authors.forename: N
authors.initials: N
authors.lastname: D'Agostino
authors.forename: C
authors.initials: C
authors.lastname: Avitabile
authors.forename: L
authors.initials: L
authors.lastname: Frusciante
authors.forename: A
authors.initials: A
authors.lastname: Barone
authors.forename: F
authors.initials: F
authors.lastname: Capuano
authors.forename: R
authors.initials: R
authors.lastname: Capparelli
mesh_terms: D000595:Amino Acid Sequence; D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000494:pharmacology*; D045744:Cell Line, Tumor; D023082:Defensins / Q000737:chemistry; D016480:Helicobacter pylori / Q000187:drug effects*; D006461:Hemolysis; D006801:Humans; D018551:Solanum lycopersicum / Q000737:chemistry; D008826:Microbial Sensitivity Tests; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000737:chemistry / Q000494:pharmacology*; D010940:Plant Proteins / Q000737:chemistry
chemical_list: D000900:Anti-Bacterial Agents; D023082:Defensins; D010446:Peptide Fragments; D010940:Plant Proteins
keywords: Helicobacter pylori; antimicrobial peptide; defensin; tomato