Novel synthetic anti-fungal tripeptide effective against Candida krusei

Indian J Med Microbiol. Jan-Mar 2015;33(1):110-6. doi: 10.4103/0255-0857.148404.

Abstract

Introduction: Candida species are the major fungal pathogens of humans. Among them, Candida krusei have emerged as a notable pathogen with a spectrum of clinical manifestations and is known to develop resistance against azoles mainly fluconazole. Anti-microbial peptides play important roles in the early mucosal defence against infection and are potent anti-fungal agents since they fight against fungal infection as well as have ability to regulate host immune defence system. The aim of the study was to synthesize a small anti fungal peptide.

Materials and methods: The series of tripeptides were synthesized and screened for antifungal activity against Candida strains according to CLSI guidelines. Toxicity effect of peptide was tested with human erythrocytes. The mode of action of peptide on fungus was resolved by scanning electron microscopy (SEM) studies Results: The tripeptide FAR showed a prominent anti fungal activity among the series. The minimum inhibitory concentration and minimum fungicidal concentration of tripeptide FAR was found to be 171.25 μg/ml and 685 μg/ml, respectively against Candida krusei . The therapeutic index was 2.9. The haemolytic experiment revealed that this peptide is non-toxic to human cells. The SEM studies showed disruption of cell wall and bleb-like surface changes and irregular cell surface.

Conclusion: The peptide showed a significant antifungal activity against C. krusei. Thus, it can set a platform for the design of new effective therapeutic agents against C. krusei.

MeSH terms

  • Antifungal Agents / chemical synthesis*
  • Antifungal Agents / pharmacology*
  • Antifungal Agents / toxicity
  • Candida / drug effects*
  • Candida / ultrastructure
  • Erythrocytes / drug effects
  • Hemolysis / drug effects
  • Humans
  • Microbial Sensitivity Tests
  • Microscopy, Electron, Scanning
  • Oligopeptides / chemical synthesis*
  • Oligopeptides / pharmacology*
  • Oligopeptides / toxicity

Substances

  • Antifungal Agents
  • Oligopeptides