title: A de novo-designed antimicrobial peptide with activity against multiresistant Staphylococcus aureus acting on RsbW kinase.
abstract: Antimicrobial peptides are a promising complement to common antibiotics, development of resistance to which is a growing problem. Here we present a de novo-designed peptide, SP1-1 (RKKRLKLLKRLL-NH2), with antimicrobial activity against multiresistant Staphylococcus aureus (minimal inhibitory concentration: 6.25 μM). Elucidation of the mode of action of this peptide revealed a strong interaction with RsbW kinase (Kd: 6.01±2.73 nM), a serine kinase negatively regulating the activity of the transcription factor σB (SigB). SP1-1 binding and functional modulation of RsbW were shown in vitro by a combination of biochemical, molecular, and biophysical methods, which were further genetically evidenced in vivo by analysis of S. aureus ΔsigB deletion mutants. Intracellular localization of the peptide was demonstrated using nanometer-scaled secondary ion mass spectrometry. Moreover, microarray analysis revealed that transcription of numerous genes, involved in cell wall and amino acid metabolism, transport mechanisms, virulence, and pigmentation, is affected. Interestingly, several WalR binding motif containing genes are induced by SP1-1. In sum, the designed peptide SP1-1 seems to have multiple modes of action, including inhibition of a kinase, and therefore might contribute to the development of new antibacterial compounds, giving bacterial kinase inhibition a closer inspection.
authors.affiliation: 1Helmholtz Zentrum Munich, Landstrasse, München-Neuherberg, D-85764 Germany. lindermayr@helmholtz-muenchen.de.
authors.forename: Alexandra
authors.initials: A
authors.lastname: Dangel
authors.forename: Nikolaus
authors.initials: N
authors.lastname: Ackermann
authors.forename: Omar
authors.initials: O
authors.lastname: Abdel-Hadi
authors.forename: Richard
authors.initials: R
authors.lastname: Maier
authors.forename: Kamil
authors.initials: K
authors.lastname: Önder
authors.forename: Patrice
authors.initials: P
authors.lastname: Francois
authors.forename: Carsten W
authors.initials: CW
authors.lastname: Müller
authors.forename: Jan
authors.initials: J
authors.lastname: Pané-Farré
authors.forename: Susanne
authors.initials: S
authors.lastname: Engelmann
authors.forename: Jacques
authors.initials: J
authors.lastname: Schrenzel
authors.forename: Jürgen
authors.initials: J
authors.lastname: Heesemann
authors.forename: Christian
authors.initials: C
authors.lastname: Lindermayr
mesh_terms: D000595:Amino Acid Sequence; D023181:Antimicrobial Cationic Peptides / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D001426:Bacterial Proteins / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D001692:Biological Transport / Q000235:genetics; D002352:Carrier Proteins / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D008969:Molecular Sequence Data; D009154:Mutation; D011485:Protein Binding; D047428:Protein Kinase Inhibitors / Q000138:chemical synthesis / Q000494:pharmacology*; D017346:Protein Serine-Threonine Kinases / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D012808:Sigma Factor / Q000235:genetics / Q000378:metabolism; D013211:Staphylococcus aureus / Q000187:drug effects* / Q000201:enzymology / Q000235:genetics; D014158:Transcription, Genetic / Q000187:drug effects; D014774:Virulence / Q000235:genetics
chemical_list: D023181:Antimicrobial Cationic Peptides; D001426:Bacterial Proteins; D002352:Carrier Proteins; D047428:Protein Kinase Inhibitors; C080358:RsbW protein, bacteria; C079011:SigB protein, Bacteria; D012808:Sigma Factor; C585481:arginyl-lysyl-lysyl-arginyl-leucyl-lysyl-leucyl-leucyl-lysyl-arginyl-leucyl-leucinamide; D017346:Protein Serine-Threonine Kinases
keywords: DNA binding; NanoSIMS; σB transcription factor