Evaluation of biofilm formation in the homozygous and heterozygous strains of vaginal Candida albicans isolates


1 Department of Parasitology and Mycology, Basic Sciences in Infectious Diseases Research Center, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran.

2 Department of Parasitology and Mycology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran.

3 3- Department of Parasitology and Mycology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.


Background and Purpose: Candida albicans is one of the most opportunistic yeasts around the world. This species has two heterozygous and homozygous strains at hyphal wall protein 1 (hwp1) gene locus. A simple method for the discrimination of these two strains is the amplification of HWP1 gene. Regarding this, the aim of this study was to discriminate C. albicans heterozygous and homozygous strains via the amplification of hwp1 gene and evaluation of biofilm formation between the strains.
Materials and Methods: A total of 60 homozygous (n=30) and heterozygous (n=30) strains were discriminated among 126 C. albicans vaginal isolates by the amplification of HWP1 gene, using specific primers. The evaluation of biofilm formation was accomplished using the visual method.
Results: According to the results, the homozygous and heterozygous strains produced one and two DNA fragments, respectively. The frequency of homozygous strains among the C. albicans vaginal isolates was 76.2%. Biofilm formation activity in the heterozygous strains was more than that in the homozygous strains. However, statistical analysis showed no significant difference between the strains in terms of biofilm formation.
Conclusion: As the findings indicated, the frequency of the heterozygous strains in C. albicans was lower than that of the homozygous strains. Both of the strains could form biofilm in the different ranges of severity. High activity of biofilm formation in heterozygous strains may set the ground for its pathogenicity.


1. Staab JF, Bradway SD, Fidel PL, Sundstrom P. Adhesive and mammalian transglutaminase substrate properties of Candida albicans Hwp1. Science. 1999; 283(5407):1535-8.
2. Padovan AC, Chaves GM, Colombo AL, Briones MR. A novel allele of HWP1, isolated from a clinical strain of Candida albicans with defective hyphal growth and biofilm formation, has deletions of Gln/Pro and Ser/Thr repeats involved in cellular adhesion. Med Mycol. 2009; 47(8):824-35.
3. Noble SM, Johnson AD. Genetics of Candida albicans, a diploid human fungal pathogen. Annu Rev Genet. 2007; 41:193-211.
4. Berman J, Sudbery PE. Candida albicans: a molecular revolution built on lessons from budding yeast. Nat Rev Genet. 2002; 3(12):918-30.
5. Shan Y, Fan S, Liu X, Li J. Prevalence of Candida albicans-closely related yeasts, Candida africana and Candida dubliniensis, in vulvovaginal candidiasis. Med Mycol. 2014; 52(6):636-40.
6. Mucci MJ, Cuestas ML, Landanburu MF, Mujica MT. Prevalence of Candida albicans, Candida dubliniensis and Candida africana in pregnant women suffering from vulvovaginal candidiasis in Argentina. Rev Iberoam Micol. 2017; 34(2):72-6.
7. Köhler JR, Fink GR. Candida albicans strains heterozygous and homozygous for mutations in mitogen-activated protein kinase signaling components have defects in hyphal development. Proc Natil Acad Sci U S A. 1996; 93(23):13223-8.
8. Deorukhkar SC, Saini S, Mathew S. Virulence factors contributing to pathogenicity of Candida tropicalis and its antifungal susceptibility profile. Int J Microbiol. 2014; 2014:456878.
9. Yigit N, Aktas E, Dagistan S, Ayyildiz A. Investigating biofilm production, coagulase and hemolytic activity in Candida species isolated from denture stomatitis patients. Eurasian J Med. 2011; 43(1):27-32.
10. Sobel JD. Pathogenesis and treatment of recurrent vulvovaginal candidiasis. Clin Infect Dis. 1992; 14(Suppl 1):S148-53.
11. Makimura K, Murayama SY, Yamaguchi H. Detection of a wide range of medically important fungi by the polymerase chain reaction. J Med Microbiol. 1994; 40(5):358-64.
12. Şeker E, Özenç E. In vitro biofilm activity of Candida species isolated from Anatolian buffaloes with mastitis in Western Turkey. Vet Arh. 2011; 81(6):723-30.
13. Romeo O, Criseo G. Molecular epidemiology of Candida albicans and its closely related yeasts Candida dubliniensis and Candida africana. J Clin Microbiol. 2009; 47(1):212-4.
14. Pakshir K, Bordbar M, Zomorodian K, Nouraei H, Khodadadi H. Evaluation of CAMP-like effect, biofilm formation, and discrimination of Candida africana from vaginal Candida albicans species. J Pathog. 2017; 2017:7126258.
15. Gumral R, Sancak B, Guzel AB, Saraçlı MA, Ilkit M. Lack of Candida africana and Candida dubliniensis in vaginal Candida albicans isolates in Turkey using HWP1 gene polymorphisms. Mycopathologia. 2011; 172(1):73-6.
16. Tsuchimori N, Sharkey LL, Fonzi WA, French SW, Edwards JE Jr, Filler SG. Reduced virulence of HWP1-deficient mutants of Candida albicans and their interactions with host cells. Infect Immun. 2000; 68(4):1997-2002.
17. Hosseini PM, Roudbar MS, Roudbary M, Bakhshi B, Farhadi Z. Hwp1 gene expression of Candida albicans and study its role in adherence. Int J Mol Clin Microbiol. 2013; 3(2):320-4.
18. Orsi CF, Borghi E, Colombari B, Neglia RG, Quaglino D, Ardizzoni A, et al. Impact of Candida albicans hyphal wall protein 1 (HWP1) genotype on biofilm production and fungal susceptibility to microglial cells. Microb Pathog. 2014; 69-70:20-7.
19. Dabiri S, Shams-Ghahfarokhi M, Razzaghi-Abyaneh M. Comparative analysis of proteinase, phospholipase, hydrophobicity and biofilm forming ability in Candida species isolated from clinical specimens. J Mycol Med. 2018; 28(3):437-42.
20. Jafari M, Salari S, Pakshir K, Zomorodian K. Exoenzyme activity and possibility identification of Candida dubliniensis among Candida albicans species isolated from vaginal candidiasis. Microb Pathog. 2017; 110:73-7.
21. Schaller M, Bein M, Korting HC, Baur S, Hamm G, Monod M, et al. The secreted aspartyl proteinases Sap1 and Sap2 cause tissue damage in an in vitro model of vaginal candidiasis based on reconstituted human vaginal epithelium. Infect Immun. 2003; 71(6):3227-34.
Volume 5, Issue 2
June 2019
Pages 37-40
  • Receive Date: 09 July 2019
  • Revise Date: 07 September 2020
  • Accept Date: 09 July 2019
  • First Publish Date: 09 July 2019