Planktonic growth and biofilm formation profiles in Candida haemulonii species complex

Med Mycol. 2017 Oct 1;55(7):785-789. doi: 10.1093/mmy/myx005.

Abstract

Candida haemulonii species complex have emerged as multidrug-resistant yeasts able to cause fungemia worldwide. However, very little is known regarding their physiology and virulence factors. In this context, planktonic growth and biofilm formation of Brazilian clinical isolates of Candida haemulonii (n = 5), Candida duobushaemulonii (n = 4), and Candida haemulonii var. vulnera (n = 3) were reported. Overall, the fungal planktonic growth curves in Sabouraud dextrose broth reached the exponential phase in 48 h at 37°C. All the clinical isolates formed biofilm on polystyrene in a time-dependent event, as judged by the parameters evaluated: biomass (crystal violet staining), metabolic activity (XTT reduction), and extracellular matrix (safranin incorporation). No statistically significant differences were observed when the average measurements among the three Candida species were compared regarding both planktonic and biofilm lifestyles; however, typical isolate-specific differences were clearly noticed in fungal growth kinetics.

Keywords: Brazilian clinical isolates; Candida haemulonii complex; biofilm formation; morphology; planktonic growth.

MeSH terms

  • Biofilms / growth & development*
  • Biomass
  • Brazil
  • Candida / growth & development
  • Candida / isolation & purification
  • Candida / pathogenicity
  • Candida / physiology*
  • Candidiasis / microbiology
  • Culture Media / chemistry
  • Gentian Violet / metabolism
  • Humans
  • Microbiological Techniques
  • Oxidation-Reduction
  • Staining and Labeling
  • Temperature
  • Tetrazolium Salts / metabolism
  • Time Factors

Substances

  • Culture Media
  • Tetrazolium Salts
  • 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-5-((phenylamino)carbonyl)-2H-tetrazolium hydroxide
  • Gentian Violet