title: Antimicrobial nodule-specific cysteine-rich peptides disturb the integrity of bacterial outer and inner membranes and cause loss of membrane potential.
abstract: BACKGROUND
  Certain legume plants produce a plethora of AMP-like peptides in their symbiotic cells. The cationic subgroup of the nodule-specific cysteine-rich (NCR) peptides has potent antimicrobial activity against gram-negative and gram-positive bacteria as well as unicellular and filamentous fungi.
  
  
  RESULTS
  It was shown by scanning and atomic force microscopies that the cationic peptides NCR335, NCR247 and Polymyxin B (PMB) affect differentially on the surfaces of Sinorhizobium meliloti bacteria. Similarly to PMB, both NCR peptides caused damages of the outer and inner membranes but at different extent and resulted in the loss of membrane potential that could be the primary reason of their antimicrobial activity.
  
  
  CONCLUSIONS
  The primary reason for bacterial cell death upon treatment with cationic NCR peptides is the loss of membrane potential.
authors.affiliation: Institute of Biochemistry, Hungarian Academy of Sciences, Temesvári körút 62, 6726, Szeged, Hungary.
authors.forename: Kata R
authors.initials: KR
authors.lastname: Mikuláss
authors.affiliation: Institute of Biophysics of the Biological Research Centre, Hungarian Academy of Sciences, Temesvári körút 62, 6726, Szeged, Hungary.
authors.forename: Krisztina
authors.initials: K
authors.lastname: Nagy
authors.affiliation: Institute of Biochemistry, Hungarian Academy of Sciences, Temesvári körút 62, 6726, Szeged, Hungary.|Department of Environmental Systems Science, Institute of Integrative Biology, Group of Theoretical Biology, ETH Zürich, Universität strasse 16, CHN K18, 8092, Zurich, Switzerland.
authors.forename: Balázs
authors.initials: B
authors.lastname: Bogos
authors.affiliation: Institute of Biophysics of the Biological Research Centre, Hungarian Academy of Sciences, Temesvári körút 62, 6726, Szeged, Hungary.
authors.forename: Zsolt
authors.initials: Z
authors.lastname: Szegletes
authors.affiliation: Institute of Biochemistry, Hungarian Academy of Sciences, Temesvári körút 62, 6726, Szeged, Hungary.
authors.forename: Etelka
authors.initials: E
authors.lastname: Kovács
authors.affiliation: Institute of Biochemistry, Hungarian Academy of Sciences, Temesvári körút 62, 6726, Szeged, Hungary.
authors.forename: Attila
authors.initials: A
authors.lastname: Farkas
authors.affiliation: Institute of Biophysics of the Biological Research Centre, Hungarian Academy of Sciences, Temesvári körút 62, 6726, Szeged, Hungary.
authors.forename: György
authors.initials: G
authors.lastname: Váró
authors.affiliation: Institute of Biochemistry, Hungarian Academy of Sciences, Temesvári körút 62, 6726, Szeged, Hungary.
authors.forename: Éva
authors.initials: É
authors.lastname: Kondorosi
authors.affiliation: Institute of Biochemistry, Hungarian Academy of Sciences, Temesvári körút 62, 6726, Szeged, Hungary. kereszta@gmail.com.
authors.forename: Attila
authors.initials: A
authors.lastname: Kereszt
mesh_terms: D023181:Antimicrobial Cationic Peptides / Q000378:metabolism / Q000494:pharmacology*; D002462:Cell Membrane / Q000187:drug effects* / Q000648:ultrastructure; D046913:Medicago truncatula / Q000502:physiology; D008564:Membrane Potentials / Q000187:drug effects*; D018625:Microscopy, Atomic Force; D008855:Microscopy, Electron, Scanning; D010940:Plant Proteins / Q000378:metabolism / Q000494:pharmacology*; D011112:Polymyxin B / Q000494:pharmacology; D053204:Root Nodules, Plant / Q000502:physiology; D016962:Sinorhizobium meliloti / Q000187:drug effects* / Q000254:growth & development / Q000648:ultrastructure
chemical_list: D023181:Antimicrobial Cationic Peptides; D010940:Plant Proteins; D011112:Polymyxin B
keywords: Antimicrobial activity; Atomic force and scanning electron microscopy; Membrane disruption