Candida nivariensis in comparison to different phenotypes of Candida glabrata

Abstract

The purpose of the study was to establish the prevalence of new Candida glabrata complex species: Candida nivariensis and Candida bracarensis isolated from clinical material, evaluate their phenotypes and the prevalence of gene family encoding extracellular glycosylphosphatidylinositol-linked aspartyl proteases, crucial for C. glabrata virulence. Study material included 224 C. glabrata clinical strains. Candida glabrata phenotypes were identified using CHROMagar Candida medium. Strains were analysed by using C. glabrata-specific PCR for the internal transcribed spacer region to confirmed the identification. To identify C. nivariensis and C. bracarensis strains, the D1/D2 region of 26S rRNA was sequenced. The prevalence of YPS-family proteases genes was detected using standard PCR method. Candida nivariensis amounted about 6% among the total number of C. glabrata strains. Candida nivariensis strains had a white phenotype on chromogenic agar media and assimilated two sugars - trehalose and glucose. Among the 13 C. nivariensis strains, 10 did not present any YPS-family protease genes. Coexistence of all detected YPS-family protease genes was specific for C. glabrata species. This study identified C. nivariensis strains; however, no C. bracarensis strains were identified. The white phenotype of C. nivariensis was confirmed. Most strains of the new species do not present any of the tested YPS genes.

First description of Candida nivariensis in Brazil: antifungal susceptibility profile and potential virulence attributes

“…The expression of YPS genes significantly increases the capacity of the fungus to survive inside human macrophages ( Krysan et al 2005) . Swoboda-Kopeć et al (2014) confirmed the prevalence of three genes ( YPS2 , YPS4 , and YPS6 ) in the majority of C. glabrata strains isolated from clinical specimens. However, the prevalence of these genes in 13 clinical isolates of C. nivariensis was low ( Swoboda-Kopeć et al 2014) .…”

“… Swoboda-Kopeć et al (2014) confirmed the prevalence of three genes ( YPS2 , YPS4 , and YPS6 ) in the majority of C. glabrata strains isolated from clinical specimens. However, the prevalence of these genes in 13 clinical isolates of C. nivariensis was low ( Swoboda-Kopeć et al 2014) . Regarding the phytase activity, C. nivariensis 893391/INCA strain and C. nivariensis WM 09.150 reference strain presented a moderate production of phytase, whereas the type strain of C. glabrata exhibited a low production of this enzyme ( Table III ).…”

“…2008 , Lockhart et al 2009 , Chowdhary et al 2010 , Gorton et al 2013 , López-Soria et al. 2013 , Sharma et al 2013 , Li et al 2014 , Swoboda-Kopeć et al 2014 , Tay et al 2014 , Feng et al 2015 ), 55 isolates of C. nivariensis have been described in 35 cases in European countries, 19 cases in Asia, and one case report in Australia ( Table I ). Therefore, there are no cases of C. nivariensis in the American continent.…”

“…MALDI-TOF analyses were later demonstrated to be an efficient tool to differentiate these species ( Gorton et al 2013 ). Since then, other cases have been reported in Europe ( Borman et al 2008 , Gorton et al 2013 , López-Soria et al 2013 , Swoboda-Kopeć et al 2014 ), Asia ( Fujita et al 2007 , Wahyuningsih et al 2008 , Chowdhary et al 2010 , Sharma et al 2013 , Li et al 2014 , Tay et al 2014 , Feng et al 2015 ), and Australia ( Lockhart et al 2009 ). The total number of C. nivariensis isolates described in the literature has been low in these countries.…”

Relationship between the Antifungal Susceptibility Profile and the Production of Virulence-Related Hydrolytic Enzymes in Brazilian Clinical Strains ofCandida glabrata

“…The yapsins (YPS) are a family of five nonsecreted glycosylphosphatidyinositol-linked aspartic proteases that have a well-known role in cell wall integrity and increase the capacity of the fungus to survive inside human macrophages [50]. A study developed by Swoboda-Kopeć et al [51] confirmed the prevalence of three genes ( YPS2 , YPS4 , and YPS6 ) in the majority of C. glabrata strains isolated from clinical specimens.…”