Email updates

Keep up to date with the latest news and content from BMC Microbiology and BioMed Central.

Open Access Highly Accessed Research article

C. albicans growth, transition, biofilm formation, and gene expression modulation by antimicrobial decapeptide KSL-W

Simon Theberge1, Abdelhabib Semlali12, Abdullah Alamri1, Kai P Leung3 and Mahmoud Rouabhia1*

Author Affiliations

1 Oral Ecology Research Group, Faculty of Dentistry, Laval University, 2420, rue de la Terrasse, Quebec G1V 0A6, QC, Canada

2 Department of Biochemistry, Genome Research Chair, College of Science King Saud University, Riyadh, Kingdom of Saudi Arabia

3 Dental and Trauma Research Detachment, US Army Institute of Surgical Research, JBSA Fort Sam Houston, San Antonio, TX, USA

For all author emails, please log on.

BMC Microbiology 2013, 13:246  doi:10.1186/1471-2180-13-246

Published: 7 November 2013

Abstract

Background

Antimicrobial peptides have been the focus of much research over the last decade because of their effectiveness and broad-spectrum activity against microbial pathogens. These peptides also participate in inflammation and the innate host defense system by modulating the immune function that promotes immune cell adhesion and migration as well as the respiratory burst, which makes them even more attractive as therapeutic agents. This has led to the synthesis of various antimicrobial peptides, including KSL-W (KKVVFWVKFK-NH2), for potential clinical use. Because this peptide displays antimicrobial activity against bacteria, we sought to determine its antifungal effect on C. albicans. Growth, hyphal form, biofilm formation, and degradation were thus examined along with EFG1, NRG1, EAP1, HWP1, and SAP 2-4-5-6 gene expression by quantitative RT-PCR.

Results

This study demonstrates that KSL-W markedly reduced C. albicans growth at both early and late incubation times. The significant effect of KSL-W on C. albicans growth was observed beginning at 10 μg/ml after 5 h of contact by reducing C. albicans transition and at 25 μg/ml by completely inhibiting C. albicans transition. Cultured C. albicans under biofilm-inducing conditions revealed that both KSL-W and amphotericin B significantly decreased biofilm formation at 2, 4, and 6 days of culture. KSL-W also disrupted mature C. albicans biofilms. The effect of KSL-W on C. albicans growth, transition, and biofilm formation/disruption may thus occur through gene modulation, as the expression of various genes involved in C. albicans growth, transition and biofilm formation were all downregulated when C. albicans was treated with KSL-W. The effect was greater when C. albicans was cultured under hyphae-inducing conditions.

Conclusions

These data provide new insight into the efficacy of KSL-W against C. albicans and its potential use as an antifungal therapy.

Keywords:
Antimicrobial peptide; KSL-W; C. albicans; Growth; Hyphae; Gene; EFG1; NRG1; HWP1; SAPs