Multiple Candida Species Detected by Molecular Technique
By LabMedica International staff writers Posted on 05 Jan 2012 |
A simplified, specific, and sensitive seminested (PCR) method has been developed to identify medically important Candida species.
Novel primer sequences were designed and the seminested PCR was capable of detecting a larger number of Candida species by using annealing temperatures of either 60 °C or 65 °C in the second round of the seminested PCR.
At the Universiti Putra Malaysia (Serdang, Selangor, Malaysia) scientists designed species-specific reverse primers (SSRPs) of 10 Candida species by retrieving at least three internal transcribed spacer (ITS) gene sequences of each species. DNA amplification was performed in a MasterCycler gradient thermocycler. To test the specificity of the method, 27 Candida clinical isolates, 10 Candida American Type Culture Collection (ATCC; Manassas, VA, USA) strains, six Aspergillus ATCC strains, one Cryptococcus neoformans clinical isolate, and one human genomic DNA from an apparently healthy human volunteer were tested.
After optimizing the PCR conditions on the MasterCycler thermocycler (Eppendorf; Hamburg, Germany), the targeted 10 Candida species showed an expected approximate size of PCR amplicons after the second round of PCR with their respective SSRPs. A similar observation was seen when tested on the 27 Candida clinical isolates of various species in the analytical specificity testing. The limit of detection for all Candida species ranged from 0.26 pg to 0.46 pg, except for Candida guilliermondii and Candida kefyr where a 10-fold increase in DNA amount was required.
The authors concluded that the advantages of the high sensitivity feature of seminested PCR were successfully applied, while the drawback usually faced, especially on the limited capability of detecting more species, was overcome. Its usage is favorable in invasive types of fungal infection cases since early rapid detection can be done. This helps to lessen the rate of drug resistance emergence and the precarious use of costly and toxic antifungal drugs for prophylaxis and treatment purposes. The study was published on December 10, 2011, in the journal Diagnostic Microbiology and Infectious Disease.
Related Links:
Universiti Putra Malaysia
American Type Culture Collection
Eppendorf
Novel primer sequences were designed and the seminested PCR was capable of detecting a larger number of Candida species by using annealing temperatures of either 60 °C or 65 °C in the second round of the seminested PCR.
At the Universiti Putra Malaysia (Serdang, Selangor, Malaysia) scientists designed species-specific reverse primers (SSRPs) of 10 Candida species by retrieving at least three internal transcribed spacer (ITS) gene sequences of each species. DNA amplification was performed in a MasterCycler gradient thermocycler. To test the specificity of the method, 27 Candida clinical isolates, 10 Candida American Type Culture Collection (ATCC; Manassas, VA, USA) strains, six Aspergillus ATCC strains, one Cryptococcus neoformans clinical isolate, and one human genomic DNA from an apparently healthy human volunteer were tested.
After optimizing the PCR conditions on the MasterCycler thermocycler (Eppendorf; Hamburg, Germany), the targeted 10 Candida species showed an expected approximate size of PCR amplicons after the second round of PCR with their respective SSRPs. A similar observation was seen when tested on the 27 Candida clinical isolates of various species in the analytical specificity testing. The limit of detection for all Candida species ranged from 0.26 pg to 0.46 pg, except for Candida guilliermondii and Candida kefyr where a 10-fold increase in DNA amount was required.
The authors concluded that the advantages of the high sensitivity feature of seminested PCR were successfully applied, while the drawback usually faced, especially on the limited capability of detecting more species, was overcome. Its usage is favorable in invasive types of fungal infection cases since early rapid detection can be done. This helps to lessen the rate of drug resistance emergence and the precarious use of costly and toxic antifungal drugs for prophylaxis and treatment purposes. The study was published on December 10, 2011, in the journal Diagnostic Microbiology and Infectious Disease.
Related Links:
Universiti Putra Malaysia
American Type Culture Collection
Eppendorf
Latest Microbiology News
- New CE-Marked Hepatitis Assays to Help Diagnose Infections Earlier
- 1 Hour, Direct-From-Blood Multiplex PCR Test Identifies 95% of Sepsis-Causing Pathogens
- Mouth Bacteria Test Could Predict Colon Cancer Progression
- Unique Metabolic Signature Could Enable Sepsis Diagnosis within One Hour of Blood Collection
- Groundbreaking Diagnostic Platform Provides AST Results With Unprecedented Speed
- Simple Blood Test Combined With Personalized Risk Model Improves Sepsis Diagnosis
- Blood Analysis Predicts Sepsis and Organ Failure in Children
- TB Blood Test Could Detect Millions of Silent Spreaders
- New Blood Test Cuts Diagnosis Time for Nontuberculous Mycobacteria Infections from Months to Hours
- New Tuberculosis Test to Expand Testing Access in Low- and Middle-Income Countries
- Rapid Test Diagnoses Tropical Disease within Hours for Faster Antibiotics Treatment
- Rapid Molecular Testing Enables Faster, More Targeted Antibiotic Treatment for Pneumonia
- Rapid AST Platform Provides Targeted Therapeutic Results Days Faster Than Current Standard of Care
- New Analysis Method Detects Pathogens in Blood Faster and More Accurately by Melting DNA
- Rapid Sepsis Test Delivers Two Days Faster Results
- Portable Rapid PCR Diagnostic to Detect Gonorrhea and Antibiotic Susceptibility