Disparity between Multilocus Enzyme Electrophoresis, Microsatellite Markers and Pulsed-Field Gel Electrophoresis in epidemiological tracking of Candida albicans.
Various molecular systems are available for epidemiological, genetic, evolutionary, taxonomic and systematic studies of innumerable fungal infections, especially those caused by the opportunistic pathogen C. albicans. A total of 75 independent oral isolates were selected in order to compare Multilocus Enzyme Electrophoresis (MLEE), Electrophoretic Karyotyping (EK) and Microsatellite Markers (Simple Sequence Repeats - SSRs), in their abilities to differentiate and group C. albicans isolates (discriminatory power), and also, to evaluate the concordance and similarity of the groups of strains determined by cluster analysis for each fingerprinting method. Isoenzyme typing was performed using eleven enzyme systems: Adh, Sdh, M1p, Mdh, Idh, Gdh, G6pdh, Asd, Cat, Po, and Lap (data previously published). The EK method consisted of chromosomal DNA separation by pulsed-field gel electrophoresis using a CHEF system. The microsatellite markers were investigated by PCR using three polymorphic loci: EF3, CDC3, and HIS3. Dendrograms were generated by the SAHN method and UPGMA algorithm based on similarity matrices (S(SM)). The discriminatory power of the three methods was over 95%, however a paired analysis among them showed a parity of 19.7-22.4% in the identification of strains. Weak correlation was also observed among the genetic similarity matrices (S(SM)(MLEE)xS(SM)(EK)xS(SM)(SSRs)). Clustering analyses showed a mean of 9+/-12.4 isolates per cluster (3.8+/-8 isolates/taxon) for MLEE, 6.2+/-4.9 isolates per cluster (4+/-4.5 isolates/taxon) for SSRs, and 4.1+/-2.3 isolates per cluster (2.6+/-2.3 isolates/taxon) for EK. A total of 45 (13%), 39 (11.2%), 5 (1.4%) and 3 (0.9%) clusters pairs from 347 showed similarity (S(J)) of 0.1-10%, 10.1-20%, 20.1-30% and 30.1-40%, respectively. Clinical and molecular epidemiological correlation involving the opportunistic pathogen C. albicans may be attributed dependently of each method of genotyping (i.e., MLEE, EK, and SSRs) supplemented with similarity and grouping analysis. Therefore, the use of genotyping systems that give results which offer minimum disparity, or the combination of the results of these systems, can provide greater security and consistency in the determination of strains and their genetic relationships.
Boriollo
Marcelo Fabiano Gomes
MF
Laboratory of Molecular Biology and Genetics, Faculty of Medical Sciences, University of Alfenas, Minas Gerais, Brazil. marcelo.boriollo@unifenas.br
Dias
Ricardo Antunes
RA
Fiorini
João Evangelista
JE
Oliveira
Nelma de Mello Silva
Nde M
Spolidório
Denise Madalena Palomari
DM
de Souza
Henrique Marques Barbosa
HM
Figueira
Antonio Vargas de Oliveira
AV
Pizzirani-Kleiner
Aline Aparecida
AA
D002176:Candida albicans / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification*; D002177:Candidiasis / Q000453:epidemiology / Q000382:microbiology*; D002675:Child, Preschool; D004586:Electrophoresis / Q000379:methods*; D016521:Electrophoresis, Gel, Pulsed-Field / Q000379:methods; D005656:Fungal Proteins / Q000235:genetics; D006801:Humans; D007621:Karyotyping; D008297:Male; D018895:Microsatellite Repeats; D017720:Molecular Epidemiology; D008969:Molecular Sequence Data; D009055:Mouth / Q000382:microbiology; D016533:Mycological Typing Techniques / Q000379:methods*; D010802:Phylogeny
D005656:Fungal Proteins