This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Balashov, S. V.
Right arrow Articles by Perlin, D. S.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Balashov, S. V.
Right arrow Articles by Perlin, D. S.

 Previous Article  |  Next Article 

Antimicrobial Agents and Chemotherapy, June 2006, p. 2058-2063, Vol. 50, No. 6
0066-4804/06/$08.00+0     doi:10.1128/AAC.01653-05
Copyright © 2006, American Society for Microbiology. All Rights Reserved.

Assessing Resistance to the Echinocandin Antifungal Drug Caspofungin in Candida albicans by Profiling Mutations in FKS1

Sergey V. Balashov,1 Steven Park,1 and David S. Perlin1,2*

Public Health Research Institute, International Center for Public Health, 225 Warren St.,1 Department of Microbiology and Molecular Genetics, New Jersey Medical School, University of Medicine and Dentistry of New Jersey, Newark, New Jersey 071032

Received 30 December 2005/ Returned for modification 28 January 2006/ Accepted 12 March 2006

Resistance of clinical isolates of Candida albicans to the echinocandin drug caspofungin is slowly emerging and is linked to mutations in short conserved regions in the FKS1 gene. The most prominent changes occurred at the serine 645 position in Fks1p with substitutions of proline, tyrosine, and phenylalanine. An allele-specific real-time PCR molecular-beacon assay was developed for rapid identification of drug resistance by targeting FKS1 mutations. Mutations altering serine 645 were reliably identified in both heterozygous and homozygous states. The molecular-beacon assay was used to evaluate two large collections of spontaneous mutants from separate strains of C. albicans with resistance (MICs, >16 µg/ml) to caspofungin with the goal of understanding the relationship between FKS1 mutations and echinocandin resistance. Of 85 resistant isolates recovered, all were identified with mutations in FKS1; 93% showed changes at Ser645, with 62% displaying a characteristic S645P substitution expressed as either a homozygous or a heterozygous mutation in FKS1. Two other prominent amino acid substitutions, S645Y and S645F, were found at frequencies of 22% and 8%, respectively. Three new mutations were also identified: T1922C, G1932T, and C1934G, encoding F641S, L644F, and S645C substitutions, respectively. One strain had the double amino acid substitution L644F and S645C. Allele-specific probes were combined in a multiplex assay for reliable screening of known FKS1 mutations. These data support the importance of FKS1p substitutions in echinocandin resistance and demonstrate the feasibility of applying molecular screening for routine resistance assessment.


* Corresponding author. Mailing address: PHRI, International Center for Public Health, 225 Warren St., Newark, NJ 07103. Phone: (973) 854-3200. Fax: (973) 854-3101. E-mail:perlin{at}phri.org.


Antimicrobial Agents and Chemotherapy, June 2006, p. 2058-2063, Vol. 50, No. 6
0066-4804/06/$08.00+0     doi:10.1128/AAC.01653-05
Copyright © 2006, American Society for Microbiology. All Rights Reserved.




This article has been cited by other articles:

  • Katiyar, S. K., Edlind, T. D. (2009). Role for Fks1 in the Intrinsic Echinocandin Resistance of Fusarium solani as Evidenced by Hybrid Expression in Saccharomyces cerevisiae. Antimicrob. Agents Chemother. 53: 1772-1778 [Abstract] [Full Text]  
  • Garcia-Effron, G., Park, S., Perlin, D. S. (2009). Correlating Echinocandin MIC and Kinetic Inhibition of fks1 Mutant Glucan Synthases for Candida albicans: Implications for Interpretive Breakpoints. Antimicrob. Agents Chemother. 53: 112-122 [Abstract] [Full Text]  
  • Garcia-Effron, G., Kontoyiannis, D. P., Lewis, R. E., Perlin, D. S. (2008). Caspofungin-Resistant Candida tropicalis Strains Causing Breakthrough Fungemia in Patients at High Risk for Hematologic Malignancies. Antimicrob. Agents Chemother. 52: 4181-4183 [Abstract] [Full Text]  
  • Wiederhold, N. P., Grabinski, J. L., Garcia-Effron, G., Perlin, D. S., Lee, S. A. (2008). Pyrosequencing To Detect Mutations in FKS1 That Confer Reduced Echinocandin Susceptibility in Candida albicans. Antimicrob. Agents Chemother. 52: 4145-4148 [Abstract] [Full Text]  
  • Desnos-Ollivier, M., Bretagne, S., Raoux, D., Hoinard, D., Dromer, F., Dannaoui, E. (2008). Mutations in the fks1 Gene in Candida albicans, C. tropicalis, and C. krusei Correlate with Elevated Caspofungin MICs Uncovered in AM3 Medium Using the Method of the European Committee on Antibiotic Susceptibility Testing. Antimicrob. Agents Chemother. 52: 3092-3098 [Abstract] [Full Text]  
  • Richards, T. S., Oliver, B. G., White, T. C. (2008). Micafungin activity against Candida albicans with diverse azole resistance phenotypes. J Antimicrob Chemother 62: 349-355 [Abstract] [Full Text]  
  • Pfaller, M. A., Diekema, D. J., Ostrosky-Zeichner, L., Rex, J. H., Alexander, B. D., Andes, D., Brown, S. D., Chaturvedi, V., Ghannoum, M. A., Knapp, C. C., Sheehan, D. J., Walsh, T. J. (2008). Correlation of MIC with Outcome for Candida Species Tested against Caspofungin, Anidulafungin, and Micafungin: Analysis and Proposal for Interpretive MIC Breakpoints. J. Clin. Microbiol. 46: 2620-2629 [Abstract] [Full Text]  
  • Garcia-Effron, G., Katiyar, S. K., Park, S., Edlind, T. D., Perlin, D. S. (2008). A Naturally Occurring Proline-to-Alanine Amino Acid Change in Fks1p in Candida parapsilosis, Candida orthopsilosis, and Candida metapsilosis Accounts for Reduced Echinocandin Susceptibility. Antimicrob. Agents Chemother. 52: 2305-2312 [Abstract] [Full Text]  
  • Desnos-Ollivier, M., Dromer, F., Dannaoui, E. (2008). Detection of Caspofungin Resistance in Candida spp. by Etest. J. Clin. Microbiol. 46: 2389-2392 [Abstract] [Full Text]  
  • Cowen, L. E., Steinbach, W. J. (2008). Stress, Drugs, and Evolution: the Role of Cellular Signaling in Fungal Drug Resistance. Eukaryot Cell 7: 747-764 [Full Text]  
  • Garcia-Effron, G., Dilger, A., Alcazar-Fuoli, L., Park, S., Mellado, E., Perlin, D. S. (2008). Rapid Detection of Triazole Antifungal Resistance in Aspergillus fumigatus. J. Clin. Microbiol. 46: 1200-1206 [Abstract] [Full Text]  
  • Angiolella, L., Stringaro, A. R., De Bernardis, F., Posteraro, B., Bonito, M., Toccacieli, L., Torosantucci, A., Colone, M., Sanguinetti, M., Cassone, A., Palamara, A. T. (2008). Increase of Virulence and Its Phenotypic Traits in Drug-Resistant Strains of Candida albicans. Antimicrob. Agents Chemother. 52: 927-936 [Abstract] [Full Text]  
  • Rocha, E. M. F., Garcia-Effron, G., Park, S., Perlin, D. S. (2007). A Ser678Pro Substitution in Fks1p Confers Resistance to Echinocandin Drugs in Aspergillus fumigatus. Antimicrob. Agents Chemother. 51: 4174-4176 [Abstract] [Full Text]  
  • Baixench, M.-T., Aoun, N., Desnos-Ollivier, M., Garcia-Hermoso, D., Bretagne, S., Ramires, S., Piketty, C., Dannaoui, E. (2007). Acquired resistance to echinocandins in Candida albicans: case report and review. J Antimicrob Chemother 59: 1076-1083 [Abstract] [Full Text]  
  • Pfaller, M. A., Diekema, D. J. (2007). Epidemiology of Invasive Candidiasis: a Persistent Public Health Problem. Clin. Microbiol. Rev. 20: 133-163 [Abstract] [Full Text]