Multilocus Sequence Typing for Analyses of Clonality of Candida Albicans Strains in Taiwan
Resource
JOURNAL OF CLINICAL MICROBIOLOGY v.44 n.6 pp.2172-2178
Journal
JOURNAL OF CLINICAL MICROBIOLOGY
Journal Volume
v.44
Journal Issue
n.6
Pages
2172-2178
Date Issued
2006
Date
2006
Author(s)
CHEN, KUO-WEI
Abstract
Multilocus sequence typing (MLST) was used to characterize the genetic profiles of 51 Candida albicans isolates collected from 12 hospitals in Taiwan. Among the 51 isolates , 16 were epidemiologically unrelated, 28 were isolates from 11 critically ill, HIV-negative patients and 7 were long- term serial isolates from 3 HIV-positive patients. Internal regions of seven housekeeping genes were sequenced. A total of 83 polymorphic nucleotide sites were identified. Ten to 20 different genotypes were observed at the different loci, resulting, when combined, in 45 unique genotype combinations or diploid sequence types (DSTs). Thirty (36.1%) of the 83 individual changes were synonymous and 53 (63.9%) nonsynonymous. Due to the diploidy nature of C. albicans, MLST was more discriminatory when compared with pulsed field gel electrophoresis (PFGE)- BssHII restricted fragments method in discriminating epidemiologically related strains. MLST is able to trace the microevolution over time of C. albicans isolates in the same patient. All but one of the DSTs of our Taiwanese strain collections were novel to the Internet C. albicans DST database ( test1.mlst.net). The DSTs of C. albicans in Taiwan were analyzed together with those of the reference strains and of the strains from the UK and USA by UPGMA and minimum spanning tree. Our result showed that the DNA type of each isolate was patient-specific and associated with ABC type and decade of isolation, but not associated with mating type, anatomical source of isolation, hospital origin, or fluconazole resistance patterns.
Subjects
Molecular Typing
Candida albicans
MLST
PFGE
Type
journal article