Multilocus Sequence Type Analysis Reveals both Clonality and Recombination in Populations of Candida glabrata Bloodstream Isolates from U.S. Surveillance Studies

Mycotic Diseases Branch, Centers for Disease Control and Prevention, Atlanta, GA 30333, USA.
Eukaryotic Cell (Impact Factor: 3.18). 02/2010; 9(4):619-25. DOI: 10.1128/EC.00002-10
Source: PubMed


The human commensal yeast Candida glabrata is becoming increasingly important as an agent of nosocomial bloodstream infection. However, relatively little is known concerning
the genetics and population structure of this species. We have analyzed 230 incident bloodstream isolates from previous and
current population-based surveillance studies by using multilocus sequence typing (MLST). Our results show that in the U.S.
cities of Atlanta, GA; Baltimore, MD; and San Francisco, CA during three time periods spanning 1992 to 2009, five populations
of C. glabrata bloodstream isolates are defined by a relatively small number of sequence types. There is little genetic differentiation
in the different C. glabrata populations. We also show that there has been a significant temporal shift in the prevalence of one major subtype in Atlanta.
Our results support the concept that both recombination and clonality play a role in the population structure of this species.

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Available from: Shawn Lockhart, May 21, 2014
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    • "Utilizing this MLST method, several studies have described the population structure of geographically diverse collections of C. glabrata isolates [43–45]. Recent MLST analysis of 230 isolates of C. glabrata from five populations that differed both geographically and temporally confirmed that the six unlinked loci provide genotypic diversity and differentiation among isolates of this species [46]. MLST studies also revealed that C. glabrata strains causing bloodstream infections have similar population structures and fluconazole susceptibilities compared to those normally residing in/on the host [47]. "
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