• Home
  • Search Results
  • Synergistic Activity of the Plant Defensin HsAFP1 and Caspofungin against Candida albicans Biofilms and Planktonic Cultures.

Synergistic Activity of the Plant Defensin HsAFP1 and Caspofungin against Candida albicans Biofilms and Planktonic Cultures.

PloS one (2015-08-08)
Kim Vriens, Tanne L Cools, Peta J Harvey, David J Craik, Pieter Spincemaille, David Cassiman, Annabel Braem, Jozef Vleugels, Peter H Nibbering, Jan Wouter Drijfhout, Barbara De Coninck, Bruno P A Cammue, Karin Thevissen
ABSTRACT

Plant defensins are small, cysteine-rich peptides with antifungal activity against a broad range of yeast and fungi. In this study we investigated the antibiofilm activity of a plant defensin from coral bells (Heuchera sanguinea), i.e. HsAFP1. To this end, HsAFP1 was heterologously produced using Pichia pastoris as a host. The recombinant peptide rHsAFP1 showed a similar antifungal activity against the plant pathogen Fusarium culmorum as native HsAFP1 purified from seeds. NMR analysis revealed that rHsAFP1 consists of an α-helix and a triple-stranded antiparallel β-sheet stabilised by four intramolecular disulfide bonds. We found that rHsAFP1 can inhibit growth of the human pathogen Candida albicans as well as prevent C. albicans biofilm formation with a BIC50 (i.e. the minimum rHsAFP1 concentration required to inhibit biofilm formation by 50% as compared to control treatment) of 11.00 ± 1.70 μM. As such, this is the first report of a plant defensin exhibiting inhibitory activity against fungal biofilms. We further analysed the potential of rHsAFP1 to increase the activity of the conventional antimycotics caspofungin and amphotericin B towards C. albicans. Synergistic effects were observed between rHsAFP1 and these compounds against both planktonic C. albicans cells and biofilms. Most notably, concentrations of rHsAFP1 as low as 0.53 μM resulted in a synergistic activity with caspofungin against pre-grown C. albicans biofilms. rHsAFP1 was found non-toxic towards human HepG2 cells up to 40 μM, thereby supporting the lack of a general cytotoxic activity as previously reported for HsAFP1. A structure-function study with 24-mer synthetic peptides spanning the entire HsAFP1 sequence revealed the importance of the γ-core and its adjacent regions for HsAFP1 antibiofilm activity. These findings point towards broad applications of rHsAFP1 and its derivatives in the field of antifungal and antibiofilm drug development.

MATERIALS
Product Number
Brand
Product Description

Sigma-Aldrich
Dimethyl sulfoxide, Hybri-Max, sterile-filtered, BioReagent, suitable for hybridoma, ≥99.7%
Sigma-Aldrich
Methanol, anhydrous, 99.8%
Sigma-Aldrich
Dimethyl sulfoxide, for molecular biology
Sigma-Aldrich
Dimethyl sulfoxide, anhydrous, ≥99.9%
Sigma-Aldrich
Methanol, HPLC Plus, ≥99.9%, poly-coated bottles
Sigma-Aldrich
Glycerol, for molecular biology, ≥99.0%
Sigma-Aldrich
Acetonitrile, anhydrous, 99.8%
Sigma-Aldrich
Dimethyl sulfoxide, sterile-filtered, BioPerformance Certified, meets EP, USP testing specifications, suitable for hybridoma
Sigma-Aldrich
Sodium bicarbonate, powder, BioReagent, for molecular biology, suitable for cell culture, suitable for insect cell culture
Sigma-Aldrich
Glycerol, ≥99.5%
Sigma-Aldrich
MOPS, ≥99.5% (titration)
Sigma-Aldrich
Dimethyl sulfoxide, ≥99.5% (GC), suitable for plant cell culture
Sigma-Aldrich
Potassium phosphate tribasic, reagent grade, ≥98%
Sigma-Aldrich
L-Glutamine, meets USP testing specifications, suitable for cell culture, 99.0-101.0%, from non-animal source
Sigma-Aldrich
Glycerol, BioReagent, suitable for cell culture, suitable for insect cell culture, suitable for electrophoresis, ≥99% (GC)
Sigma-Aldrich
L-Glutamine, ReagentPlus®, ≥99% (HPLC)
Sigma-Aldrich
Acetonitrile solution, contains 0.1 % (v/v) trifluoroacetic acid, suitable for HPLC
Sigma-Aldrich
Dimethyl sulfoxide, meets EP testing specifications, meets USP testing specifications
Sigma-Aldrich
Sodium bicarbonate, BioXtra, 99.5-100.5%
Sigma-Aldrich
MOPS, BioPerformance Certified, suitable for cell culture, ≥99.5% (titration)
SAFC
L-Glutamine
Sigma-Aldrich
Glycerin, meets USP testing specifications
Sigma-Aldrich
Glycerol, BioXtra, ≥99% (GC)
Sigma-Aldrich
Glycerol solution, 83.5-89.5% (T)
Sigma-Aldrich
Dimethyl sulfoxide, BioUltra, for molecular biology, ≥99.5% (GC)
Sigma-Aldrich
Glycerol, FCC, FG
Sigma-Aldrich
Dimethyl sulfoxide, PCR Reagent
Sigma-Aldrich
Glycerol, BioUltra, for molecular biology, anhydrous, ≥99.5% (GC)
Sigma-Aldrich
Acetonitrile solution, contains 0.1 % (v/v) formic acid, suitable for HPLC
Sigma-Aldrich
Nitrogen, ≥99.998%