Performance of CHROMAGAR candida and BIGGY agar for identification of yeast species.

PubMed

Yücesoy, Mine; Marol, Serhat

2003-10-29

The importance of identifying the pathogenic fungi rapidly has encouraged the development of differential media for the presumptive identification of yeasts. In this study two differential media, CHROMagar Candida and bismuth sulphite glucose glycine yeast agar, were evaluated for the presumptive identification of yeast species. A total number of 270 yeast strains including 169 Candida albicans, 33 C. tropicalis, 24 C. glabrata, 18 C. parapsilosis, 12 C. krusei, 5 Trichosporon spp., 4 C. kefyr, 2 C. lusitaniae, 1 Saccharomyces cerevisiae and 1 Geotrichum candidum were included. The strains were first identified by germ tube test, morphological characteristics on cornmeal tween 80 agar and Vitek 32 and API 20 C AUX systems. In parallel, they were also streaked onto CHROMagar Candida and bismuth sulphite glucose glycine yeast agar plates. The results were read according to the color, morphology of the colonies and the existance of halo around them after 48 hours of incubation at 37 degrees C. The sensitivity and specificity values for C. albicans strains were found to be 99.4, 100% for CHROMagar Candida and 87.0, 75.2% for BiGGY agar, respectively. The sensitivity of CHROMagar Candida to identify C. tropicalis, C. glabrata and C. krusei ranged between 90.9 and 100% while the specificity was 100%. The sensitivity rates for BiGGY agar were 66.6 and 100% while the specificity values were found to be 95.4 and 100% for C. tropicalis and C. krusei, respectively. It can be concluded that the use of CHROMagar Candida is an easy and reliable method for the presumptive identification of most commonly isolated Candida species especially C. albicans, C. tropicalis and C. krusei. The lower sensitivity and specificity of BiGGY agar to identify commonly isolated Candida species potentially limits the clinical usefulness of this agar.

Performance of CHROMAGAR candida and BIGGY agar for identification of yeast species

PubMed Central

Yücesoy, Mine; Marol, Serhat

2003-01-01

Background The importance of identifying the pathogenic fungi rapidly has encouraged the development of differential media for the presumptive identification of yeasts. In this study two differential media, CHROMagar Candida and bismuth sulphite glucose glycine yeast agar, were evaluated for the presumptive identification of yeast species. Methods A total number of 270 yeast strains including 169 Candida albicans, 33 C. tropicalis, 24 C. glabrata, 18 C. parapsilosis, 12 C. krusei, 5 Trichosporon spp., 4 C. kefyr, 2 C. lusitaniae, 1 Saccharomyces cerevisiae and 1 Geotrichum candidum were included. The strains were first identified by germ tube test, morphological characteristics on cornmeal tween 80 agar and Vitek 32 and API 20 C AUX systems. In parallel, they were also streaked onto CHROMagar Candida and bismuth sulphite glucose glycine yeast agar plates. The results were read according to the color, morphology of the colonies and the existance of halo around them after 48 hours of incubation at 37°C. Results The sensitivity and specificity values for C. albicans strains were found to be 99.4, 100% for CHROMagar Candida and 87.0, 75.2% for BiGGY agar, respectively. The sensitivity of CHROMagar Candida to identify C. tropicalis, C. glabrata and C. krusei ranged between 90.9 and 100% while the specificity was 100%. The sensitivity rates for BiGGY agar were 66.6 and 100% while the specificity values were found to be 95.4 and 100% for C. tropicalis and C. krusei, respectively. Conclusions It can be concluded that the use of CHROMagar Candida is an easy and reliable method for the presumptive identification of most commonly isolated Candida species especially C. albicans, C. tropicalis and C. krusei. The lower sensitivity and specificity of BiGGY agar to identify commonly isolated Candida species potentially limits the clinical usefulness of this agar. PMID:14613587

Multifunctional centromere binding factor 1 is essential for chromosome segregation in the human pathogenic yeast Candida glabrata.

PubMed

Stoyan, T; Gloeckner, G; Diekmann, S; Carbon, J

2001-08-01

The CBF1 (centromere binding factor 1) gene of Candida glabrata was cloned by functional complementation of the methionine biosynthesis defect of a Saccharomyces cerevisiae cbf1 deletion mutant. The C. glabrata-coded protein, CgCbf1, contains a basic-helix-loop-helix leucine zipper domain and has features similar to those of other budding yeast Cbf1 proteins. CgCbf1p binds in vitro to the centromere DNA element I (CDEI) sequence GTCACATG with high affinity (0.9 x 10(9) M(-1)). Bandshift experiments revealed a pattern of protein-DNA complexes on CgCEN DNA different from that known for S. cerevisiae. We examined the effect of altering the CDEI binding site on CEN plasmid segregation, using a newly developed colony-sectoring assay. Internal deletion of the CDEI binding site led only to a fivefold increase in rates of plasmid loss, indicating that direct binding of Cbf1p to the centromere DNA is not required for full function. Additional deletion of sequences to the left of CDEI, however, led to a 70-fold increase in plasmid loss rates. Deletion of the CBF1 gene proved to be lethal in C. glabrata. C. glabrata cells containing the CBF1 gene under the influence of a shutdown promoter (tetO-ScHOP) arrested their growth after 5 h of cultivation in the presence of the reactive drug doxycycline. DAPI (4',6'-diamidino-2-phenylindole) staining of the arrested cells revealed a significant increase in the number of large-budded cells with single nuclei, 2C DNA content, and short spindles, indicating a defect in the G(2)/M transition of the cell cycle. Thus, we conclude that Cbf1p is required for chromosome segregation in C. glabrata.

Candida glabrata Binding to Candida albicans Hyphae Enables Its Development in Oropharyngeal Candidiasis

PubMed Central

Tati, Swetha; Davidow, Peter; McCall, Andrew; Hwang-Wong, Elizabeth; Rojas, Isolde G.; Cormack, Brendan; Edgerton, Mira

2016-01-01

Pathogenic mechanisms of Candida glabrata in oral candidiasis, especially because of its inability to form hyphae, are understudied. Since both Candida albicans and C. glabrata are frequently co-isolated in oropharyngeal candidiasis (OPC), we examined their co-adhesion in vitro and observed adhesion of C. glabrata only to C. albicans hyphae microscopically. Mice were infected sublingually with C. albicans or C. glabrata individually, or with both species concurrently, to study their ability to cause OPC. Infection with C. glabrata alone resulted in negligible infection of tongues; however, colonization by C. glabrata was increased by co-infection or a pre-established infection with C. albicans. Furthermore, C. glabrata required C. albicans for colonization of tongues, since decreasing C. albicans burden with fluconazole also reduced C. glabrata. C. albicans hyphal wall adhesins Als1 and Als3 were important for in vitro adhesion of C. glabrata and to establish OPC. C. glabrata cell wall protein coding genes EPA8, EPA19, AWP2, AWP7, and CAGL0F00181 were implicated in mediating adhesion to C. albicans hyphae and remarkably, their expression was induced by incubation with germinated C. albicans. Thus, we found a near essential requirement for the presence of C. albicans for both initial colonization and establishment of OPC infection by C. glabrata. PMID:27029023

Differentiation of Candida albicans, Candida glabrata, and Candida krusei by FT-IR and chemometrics by CHROMagar™ Candida.

PubMed

Wohlmeister, Denise; Vianna, Débora Renz Barreto; Helfer, Virginia Etges; Calil, Luciane Noal; Buffon, Andréia; Fuentefria, Alexandre Meneghello; Corbellini, Valeriano Antonio; Pilger, Diogo André

2017-10-01

Pathogenic Candida species are detected in clinical infections. CHROMagar™ is a phenotypical method used to identify Candida species, although it has limitations, which indicates the need for more sensitive and specific techniques. Infrared Spectroscopy (FT-IR) is an analytical vibrational technique used to identify patterns of metabolic fingerprint of biological matrixes, particularly whole microbial cell systems as Candida sp. in association of classificatory chemometrics algorithms. On the other hand, Soft Independent Modeling by Class Analogy (SIMCA) is one of the typical algorithms still little employed in microbiological classification. This study demonstrates the applicability of the FT-IR-technique by specular reflectance associated with SIMCA to discriminate Candida species isolated from vaginal discharges and grown on CHROMagar™. The differences in spectra of C. albicans, C. glabrata and C. krusei were suitable for use in the discrimination of these species, which was observed by PCA. Then, a SIMCA model was constructed with standard samples of three species and using the spectral region of 1792-1561cm -1 . All samples (n=48) were properly classified based on the chromogenic method using CHROMagar™ Candida. In total, 93.4% (n=45) of the samples were correctly and unambiguously classified (Class I). Two samples of C. albicans were classified correctly, though these could have been C. glabrata (Class II). Also, one C. glabrata sample could have been classified as C. krusei (Class II). Concerning these three samples, one triplicate of each was included in Class II and two in Class I. Therefore, FT-IR associated with SIMCA can be used to identify samples of C. albicans, C. glabrata, and C. krusei grown in CHROMagar™ Candida aiming to improve clinical applications of this technique. Copyright © 2017 Elsevier B.V. All rights reserved.

Relative Abundances of Candida albicans and Candida glabrata in In Vitro Coculture Biofilms Impact Biofilm Structure and Formation.

PubMed

Olson, Michelle L; Jayaraman, Arul; Kao, Katy C

2018-04-15

Candida is a member of the normal human microbiota and often resides on mucosal surfaces such as the oral cavity or the gastrointestinal tract. In addition to their commensality, Candida species can opportunistically become pathogenic if the host microbiota is disrupted or if the host immune system becomes compromised. An important factor for Candida pathogenesis is its ability to form biofilm communities. The two most medically important species- Candida albicans and Candida glabrata -are often coisolated from infection sites, suggesting the importance of Candida coculture biofilms. In this work, we report that biofilm formation of the coculture population depends on the relative ratio of starting cell concentrations of C. albicans and C. glabrata When using a starting ratio of C. albicans to C. glabrata of 1:3, ∼6.5- and ∼2.5-fold increases in biofilm biomass were observed relative to those of a C. albicans monoculture and a C. albicans / C. glabrata ratio of 1:1, respectively. Confocal microscopy analysis revealed the heterogeneity and complex structures composed of long C. albicans hyphae and C. glabrata cell clusters in the coculture biofilms, and reverse transcription-quantitative PCR (qRT-PCR) studies showed increases in the relative expression of the HWP1 and ALS3 adhesion genes in the C. albicans / C. glabrata 1:3 biofilm compared to that in the C. albicans monoculture biofilm. Additionally, only the 1:3 C. albicans / C. glabrata biofilm demonstrated an increased resistance to the antifungal drug caspofungin. Overall, the results suggest that interspecific interactions between these two fungal pathogens increase biofilm formation and virulence-related gene expression in a coculture composition-dependent manner. IMPORTANCE Candida albicans and Candida glabrata are often coisolated during infection, and the occurrence of coisolation increases with increasing inflammation, suggesting possible synergistic interactions between the two Candida species in

The mating type-like loci of Candida glabrata.

PubMed

Yáñez-Carrillo, Patricia; Robledo-Márquez, Karina A; Ramírez-Zavaleta, Candy Y; De Las Peñas, Alejandro; Castaño, Irene

2014-01-01

Candida glabrata, a haploid and opportunistic fungal pathogen that has not known sexual cycle, has conserved the majority of the genes required for mating and cell type identity. The C. glabrata genome contains three mating-type-like loci called MTL1, MTL2 and MTL3. The three loci encode putative transcription factors, a1, α1 and α2 that regulate cell type identity and sexual reproduction in other fungi like the closely related Saccharomyces cerevisiae. MTL1 can contain either a or α information. MTL2, which contains a information and MTL3 with α information, are relatively close to two telomeres. MTL1 and MTL2 are transcriptionally active, while MTL3 is subject to an incomplete silencing nucleated at the telomere that depends on the silencing proteins Sir2, Sir3, Sir4, yKu70/80, Rif1, Rap1 and Sum1. C. glabrata does not seem to maintain cell type identity, as cell type-specific genes are expressed regardless of the type (or even absence) of mating information. These data highlight important differences in the control of mating and cell type identity between the non-pathogenic yeast S. cerevisiae and C. glabrata, which might explain the absence of a sexual cycle in C. glabrata. The fact that C. glabrata has conserved the vast majority of the genes involved in mating might suggest that some of these genes perhaps have been rewired to control other processes important for the survival inside the host as a commensal or as a human pathogen. This manuscript is part of the series of works presented at the "V International Workshop: Molecular genetic approaches to the study of human pathogenic fungi" (Oaxaca, Mexico, 2012). Copyright © 2013 Revista Iberoamericana de Micología. Published by Elsevier Espana. All rights reserved.

Persistence of Pigment Production by Yeast Isolates Grown on CHROMagar Candida Medium

PubMed Central

Hospenthal, Duane R.; Murray, Clinton K.; Beckius, Miriam L.; Green, Judith A.; Dooley, David P.

2002-01-01

We evaluated the persistence of pigmentation in yeast isolates grown on the chromogenic medium CHROMagar Candida over 7 days. Candida, Cryptococcus, and Trichosporon isolates were inoculated alone or mixed onto duplicate sets of plates and incubated at 30 and 35°C. Candida albicans and Candida krusei were readily identified throughout the reading period, but Candida glabrata was difficult to differentiate from other species until the 3- or 4-day time point. Candida tropicalis produced colonies similar to those of rare Cryptococcus and Trichosporon species, and mixed cultures were often difficult to identify as such. PMID:12454192

Expression of Candida glabrata adhesins following exposure to chemical preservatives

PubMed Central

Mundy, Renee Domergue; Cormack, Brendan

2014-01-01

In Candida glabrata, an opportunistic yeast pathogen, adherence to host cells is mediated in part by the Epa family of adhesins, which are encoded largely at subtelomeric loci where they are subject to transcriptional silencing. In analyzing the regulation of the subtelomeric EPA6 gene, we found that its transcription is highly induced after exposure to methylparaben, propylparaben or sorbate. These weak acid-related chemicals are widely used as antifungal preservatives in many consumer goods, including over-the-counter (OTC) vaginal products. Culture of C. glabrata in a variety of vaginal products induced expression of EPA6, leading to increased adherence to cultured human cells as well as primary human vaginal epithelial cells. We present evidence that paraben/sorbate-induction of EPA6 expression involves both preservative stress and growth under hypoxic conditions. We further show that activation of EPA6 transcription depends on the Flo8 and Mss11 transcription factors and does not require the classical weak acid transcription factors War1 or Msn2/Msn4. We conclude that exposure of C. glabrata to commonly used preservatives can alter expression of virulence-related genes. PMID:19426114

Unexpected effects of azole transporter inhibitors on antifungal susceptibility in Candida glabrata and other pathogenic Candida species

PubMed Central

Nagayoshi, Yohsuke; Shimamura, Shintaro; Nakayama, Hironobu; Minematsu, Asuka; Yamauchi, Shunsuke; Takazono, Takahiro; Nakamura, Shigeki; Yanagihara, Katsunori; Kohno, Shigeru; Mukae, Hiroshi; Izumikawa, Koichi

2017-01-01

The pathogenic fungus Candida glabrata is often resistant to azole antifungal agents. Drug efflux through azole transporters, such as Cdr1 and Cdr2, is a key mechanism of azole resistance and these genes are under the control of the transcription factor Pdr1. Recently, the monoamine oxidase A (MAO-A) inhibitor clorgyline was shown to inhibit the azole efflux pumps, leading to increased azole susceptibility in C. glabrata. In the present study, we have evaluated the effects of clorgyline on susceptibility of C. glabrata to not only azoles, but also to micafungin and amphotericin B, using wild-type and several mutant strains. The addition of clorgyline to the culture media increased fluconazole susceptibility of a C. glabrata wild-type strain, whereas micafungin and amphotericin B susceptibilities were markedly decreased. These phenomena were also observed in other medically important Candida species, including Candida albicans, Candida parapsilosis, Candida tropicalis, and Candida krusei. Expression levels of CDR1, CDR2 and PDR1 mRNAs and an amount of Cdr1 protein in the C. glabrata wild-type strain were highly increased in response to the treatment with clorgyline. However, loss of Cdr1, Cdr2, Pdr1, and a putative clorgyline target (Fms1), which is an ortholog of human MAO-A, or overexpression of CDR1 did not affect the decreased susceptibility to micafungin and amphotericin B in the presence of clorgyline. The presence of other azole efflux pump inhibitors including milbemycin A4 oxime and carbonyl cyanide 3-chlorophenylhydrazone also decreased micafungin susceptibility in C. glabrata wild-type, Δcdr1, Δcdr2, and Δpdr1 strains. These findings suggest that azole efflux pump inhibitors increase azole susceptibility but concurrently induce decreased susceptibility to other classes of antifungals independent of azole transporter functions. PMID:28700656

Unexpected effects of azole transporter inhibitors on antifungal susceptibility in Candida glabrata and other pathogenic Candida species.

PubMed

Nagayoshi, Yohsuke; Miyazaki, Taiga; Shimamura, Shintaro; Nakayama, Hironobu; Minematsu, Asuka; Yamauchi, Shunsuke; Takazono, Takahiro; Nakamura, Shigeki; Yanagihara, Katsunori; Kohno, Shigeru; Mukae, Hiroshi; Izumikawa, Koichi

2017-01-01

The pathogenic fungus Candida glabrata is often resistant to azole antifungal agents. Drug efflux through azole transporters, such as Cdr1 and Cdr2, is a key mechanism of azole resistance and these genes are under the control of the transcription factor Pdr1. Recently, the monoamine oxidase A (MAO-A) inhibitor clorgyline was shown to inhibit the azole efflux pumps, leading to increased azole susceptibility in C. glabrata. In the present study, we have evaluated the effects of clorgyline on susceptibility of C. glabrata to not only azoles, but also to micafungin and amphotericin B, using wild-type and several mutant strains. The addition of clorgyline to the culture media increased fluconazole susceptibility of a C. glabrata wild-type strain, whereas micafungin and amphotericin B susceptibilities were markedly decreased. These phenomena were also observed in other medically important Candida species, including Candida albicans, Candida parapsilosis, Candida tropicalis, and Candida krusei. Expression levels of CDR1, CDR2 and PDR1 mRNAs and an amount of Cdr1 protein in the C. glabrata wild-type strain were highly increased in response to the treatment with clorgyline. However, loss of Cdr1, Cdr2, Pdr1, and a putative clorgyline target (Fms1), which is an ortholog of human MAO-A, or overexpression of CDR1 did not affect the decreased susceptibility to micafungin and amphotericin B in the presence of clorgyline. The presence of other azole efflux pump inhibitors including milbemycin A4 oxime and carbonyl cyanide 3-chlorophenylhydrazone also decreased micafungin susceptibility in C. glabrata wild-type, Δcdr1, Δcdr2, and Δpdr1 strains. These findings suggest that azole efflux pump inhibitors increase azole susceptibility but concurrently induce decreased susceptibility to other classes of antifungals independent of azole transporter functions.

Production of White Colonies on CHROMagar Candida(TM) by Members of the Candida glabrata Clade and Other Species with Overlapping Phenotypic Traits

USDA-ARS?s Scientific Manuscript database

We hypothesized that species of the Candida glabrata clade and species with phenotypic traits overlapping with C. glabrata would produce white colonies on CHROMagar Candida. Of 154 isolates (seven species) tested, C. bracarensis, C. nivariensis, C. norvegensis, C. glabrata, and C. inconspicua produ...

In Vitro Fungicidal Activities of Anidulafungin, Caspofungin, and Micafungin against Candida glabrata, Candida bracarensis, and Candida nivariensis Evaluated by Time-Kill Studies

PubMed Central

Gil-Alonso, Sandra; Jauregizar, Nerea; Cantón, Emilia; Eraso, Elena

2015-01-01

Anidulafungin, caspofungin, and micafungin killing activities against Candida glabrata, Candida bracarensis, and Candida nivariensis were evaluated by the time-kill methodology. The concentrations assayed were 0.06, 0.125, and 0.5 μg/ml, which are achieved in serum. Anidulafungin and micafungin required between 13 and 26 h to reach the fungicidal endpoint (99.9% killing) against C. glabrata and C. bracarensis. All echinocandins were less active against C. nivariensis. PMID:25801575

Candida glabrata Biofilms: How Far Have We Come?

PubMed Central

Rodrigues, Célia F.; Rodrigues, Maria Elisa; Silva, Sónia; Henriques, Mariana

2017-01-01

Infections caused by Candida species have been increasing in the last decades and can result in local or systemic infections, with high morbidity and mortality. After Candida albicans, Candida glabrata is one of the most prevalent pathogenic fungi in humans. In addition to the high antifungal drugs resistance and inability to form hyphae or secret hydrolases, C. glabrata retain many virulence factors that contribute to its extreme aggressiveness and result in a low therapeutic response and serious recurrent candidiasis, particularly biofilm formation ability. For their extraordinary organization, especially regarding the complex structure of the matrix, biofilms are very resistant to antifungal treatments. Thus, new approaches to the treatment of C. glabrata’s biofilms are emerging. In this article, the knowledge available on C. glabrata’s resistance will be highlighted, with a special focus on biofilms, as well as new therapeutic alternatives to control them. PMID:29371530

In vivo Candida glabrata biofilm development on foreign bodies in a rat subcutaneous model.

PubMed

Kucharíková, Soňa; Neirinck, Bram; Sharma, Nidhi; Vleugels, Jef; Lagrou, Katrien; Van Dijck, Patrick

2015-03-01

Biofilm studies have been mostly dedicated to the major human fungal pathogen Candida albicans, whereas much less is known about this virulence factor in Candida glabrata, certainly under in vivo conditions. This study provides a deeper understanding of the biofilm development of C. glabrata, its architecture and susceptibility profile to fluconazole and echinocandins. In vitro and in vivo C. glabrata biofilms were developed inside serum-coated triple-lumen catheters placed in 24-well polystyrene plates or implanted subcutaneously in the back of a rat, respectively. Scanning electron microscopy and confocal scanning laser microscopy were used to visualize the biofilm architecture. Quantitative real-time PCR was used to demonstrate the expression profile of EPA1, EPA3, EPA6 and AWP1-AWP7 during in vivo biofilm formation. Mature biofilms were observed within the first 48 h and the amount of biofilm reached its maximum by 6 days. Architecturally, mature C. glabrata biofilms consisted of a thick network of yeast cells embedded in an extracellular matrix. Moreover, in vivo biofilms were susceptible to echinocandin drugs, whereas fluconazole remained ineffective. Gene expression profiling revealed that EPA3, EPA6, AWP2, AWP3 and AWP5 were up-regulated in in vivo biofilms compared with in vitro biofilms. C. glabrata is a unique microorganism, which, despite the lack of transition to the hyphal form, formed thick biofilms inside foreign bodies in vivo. To our knowledge, this is the first study that has described in vivo C. glabrata biofilm development and its architectural changes in detail and provides an insight into the susceptibility profile, as well as the gene expression machinery, of biofilm-associated infections. © The Author 2014. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Identification of Candida glabrata genes involved in pH modulation and modification of the phagosomal environment in macrophages.

PubMed

Kasper, Lydia; Seider, Katja; Gerwien, Franziska; Allert, Stefanie; Brunke, Sascha; Schwarzmüller, Tobias; Ames, Lauren; Zubiria-Barrera, Cristina; Mansour, Michael K; Becken, Ulrike; Barz, Dagmar; Vyas, Jatin M; Reiling, Norbert; Haas, Albert; Haynes, Ken; Kuchler, Karl; Hube, Bernhard

2014-01-01

Candida glabrata currently ranks as the second most frequent cause of invasive candidiasis. Our previous work has shown that C. glabrata is adapted to intracellular survival in macrophages and replicates within non-acidified late endosomal-stage phagosomes. In contrast, heat killed yeasts are found in acidified matured phagosomes. In the present study, we aimed at elucidating the processes leading to inhibition of phagosome acidification and maturation. We show that phagosomes containing viable C. glabrata cells do not fuse with pre-labeled lysosomes and possess low phagosomal hydrolase activity. Inhibition of acidification occurs independent of macrophage type (human/murine), differentiation (M1-/M2-type) or activation status (vitamin D3 stimulation). We observed no differential activation of macrophage MAPK or NFκB signaling cascades downstream of pattern recognition receptors after internalization of viable compared to heat killed yeasts, but Syk activation decayed faster in macrophages containing viable yeasts. Thus, delivery of viable yeasts to non-matured phagosomes is likely not triggered by initial recognition events via MAPK or NFκB signaling, but Syk activation may be involved. Although V-ATPase is abundant in C. glabrata phagosomes, the influence of this proton pump on intracellular survival is low since blocking V-ATPase activity with bafilomycin A1 has no influence on fungal viability. Active pH modulation is one possible fungal strategy to change phagosome pH. In fact, C. glabrata is able to alkalinize its extracellular environment, when growing on amino acids as the sole carbon source in vitro. By screening a C. glabrata mutant library we identified genes important for environmental alkalinization that were further tested for their impact on phagosome pH. We found that the lack of fungal mannosyltransferases resulted in severely reduced alkalinization in vitro and in the delivery of C. glabrata to acidified phagosomes. Therefore, protein

Candida species isolated from different body sites and their antifungal susceptibility pattern: Cross-analysis of Candida albicans and Candida glabrata biofilms.

PubMed

Cataldi, Valentina; Di Campli, Emanuela; Fazii, Paolo; Traini, Tonino; Cellini, Luigina; Di Giulio, Mara

2017-08-01

Candida species are regular commensal in humans, but-especially in immunocompromised patients-they represent opportunistic pathogens giving rise to systemic infection. The aim of the present work was to isolate and characterize for their antifungal profile Candida species from different body sites and to analyze the biofilms produced by C. albicans and C. glabrata isolates. Eighty-one strains of Candida species from 77 patients were identified. Epidemiological study showed that the most isolated species were C. albicans (44), C. glabrata (13) and C. parapsilosis (13) mainly from Hematology, Infectious Diseases, Medicine, Neonatology and Oncology Divisions, the majority of the biological samples were swabs (44) and blood cultures (16). The analysis of the biofilm formation was performed at 24 and 48-hours comparing resistant and susceptible strains of C. albicans to resistant and susceptible strains of C. glabrata. Candida albicans has a greater ability to form biofilm compared to C. glabrata, both in the susceptible and resistant strains reaching maturity after 24 hours with a complex structure composed of blastospores, pseudohyphae, and hyphae embedded in a matrix. On the contrary, C. glabrata biofilm was composed exclusively of blastospores that in the resistant strain, after 24 hours, were organized in a compact multilayer different to the discontinuous structure observed in the susceptible analyzed strains. In conclusion, the increasing of the incidence of Candida species infection together with their emerging drug resistance also related to the biofilm forming capability underline the need to monitor their distribution and susceptibility patterns for improving the surveillance and for a correct management of the infection. © The Author 2016. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Candida uthaithanina sp. nov., an anamorphic yeast species in Nakaseomyces clade isolated in Thailand.

PubMed

Limtong, Savitree; Jindamorakot, Sasitorn; Am-In, Somjit; Kaewwichian, Rungluk; Nitiyon, Sukanya; Yongmanitchai, Wichien; Nakase, Takashi

2011-05-01

Three yeast stains were isolated from two unknown fruits (strains DD2-22-1(T) and SK44) and moss (strain ST-449) in Thailand. Analysis of the D1/D2 domain of the large subunit (LSU) rRNA gene sequences of the three strains revealed that they belonged to the same species. In terms of pairwise sequence similarity, Candida cf. glabrata UWO(PS) 98-110.4 and Candida nivariensis were the closest undescribed and recognized taxa, but the levels of nucleotide substitutions were 1.7-1.9% and 2.0-2.2%, respectively. The levels of nucleotide substitutions were sufficient to justify the description of a separate species of Candida. In the phylogenetic tree based on the D1/D2 domain of the LSU rRNA gene the three strains were placed in a separate branch in the Nakaseomyces clade with C. cf. glabrata UWO(PS)98-110.4, C. nivariensis, Candida glabrata, Candida bracarensis, Candida kungkrabaensis and Nakaseomyces delphensis. Phenotypic characteristics of the three strains were similar which included proliferation by multilateral budding, absence of ascospores, arthrospores or ballistospores; negative for Diazonium blue B and urease tests. The major ubiquinone was Q-6. On the basis of the above findings, the three strains were assigned to a single novel species of Candida, for which the name Candida uthaithanina sp. nov is proposed. The type strain is DD2-22-1(T) (= BCC 29899(T) = NBRC 104876(T) = CBS 10932(T)).

Expression Plasmids for Use in Candida glabrata

PubMed Central

Zordan, Rebecca E.; Ren, Yuxia; Pan, Shih-Jung; Rotondo, Giuseppe; Peñas, Alejandro De Las; Iluore, Joseph; Cormack, Brendan P.

2013-01-01

We describe a series of CEN/ARS episomal plasmids containing different Candida glabrata promoters, allowing for a range of constitutive or regulated expression of proteins in C. glabrata. The set of promoters includes three constitutive promoters (EGD2pr, HHT2pr, PDC1pr), two macrophage/phagocytosis-induced promoters (ACO2pr, LYS21pr), and one nutritionally regulated promoter (MET3pr). Each promoter was cloned into two plasmid backbones that differ in their selectable marker, URA3, or the dominant-selectable NAT1 gene, which confers resistance to the drug nourseothricin. Expression from the 12 resulting plasmids was assessed using GFP as a reporter and flow cytometry or quantitative reverse-transcription polymerase chain reaction to assess expression levels. Together this set of plasmids expands the toolkit of expression vectors available for use with C. glabrata. PMID:23934995

Direct Isolation of Candida spp. from Blood Cultures on the Chromogenic Medium CHROMagar Candida

PubMed Central

Horvath, Lynn L.; Hospenthal, Duane R.; Murray, Clinton K.; Dooley, David P.

2003-01-01

CHROMagar Candida is a selective and differential chromogenic medium that has been shown to be useful for identification of Candida albicans, Candida krusei, Candida tropicalis, and perhaps Candida glabrata. Colony morphology and color have been well defined when CHROMagar Candida has been used to isolate yeast directly from clinical specimens, including stool, urine, respiratory, vaginal, oropharyngeal, and esophageal sources. Direct isolation of yeast on CHROMagar Candida from blood cultures has not been evaluated. We evaluated whether the color and colony characteristics produced by Candida spp. on CHROMagar Candida were altered when yeasts were isolated directly from blood cultures. Fifty clinical isolates of Candida were inoculated into aerobic and anaerobic blood culture bottles and incubated at 35°C in an automated blood culture system. When growth was detected, an aliquot was removed and plated onto CHROMagar Candida. As a control, CHROMagar Candida plates were inoculated with the same isolate of yeast grown on Sabouraud dextrose agar simultaneously. No significant difference was detected in color or colony morphology between the blood and control isolates in any of the tested organisms. All C. albicans (n = 12), C. tropicalis (n = 12), C. glabrata (n = 9), and C. krusei (n = 5) isolates exhibited the expected species-specific colony characteristics and color, whether isolated directly from blood or from control cultures. CHROMagar Candida can be reliably used for direct isolation of yeast from blood cultures. Direct isolation could allow mycology laboratories to more rapidly identify Candida spp., enable clinicians to more quickly make antifungal agent selections, and potentially decrease patient morbidity and mortality. PMID:12791890

Accuracy of Sensititre YeastOne Echinocandins Epidemiological Cut-off Values for Identification of FKS mutant Candida albicans and Candida glabrata: A Ten Year National Survey of the Fungal Infection Network of Switzerland (FUNGINOS).

PubMed

Kritikos, A; Neofytos, D; Khanna, N; Schreiber, P W; Boggian, K; Bille, J; Schrenzel, J; Mühlethaler, K; Zbinden, R; Bruderer, T; Goldenberger, D; Pfyffer, G; Conen, A; Van Delden, C; Zimmerli, S; Sanglard, D; Bachmann, D; Marchetti, O; Lamoth, F

2018-06-14

Echinocandins represent the first-line treatment of candidemia. Acquired echinocandin resistance is mainly observed among Candida albicans and glabrata and is associated with FKS hotspot mutations. The commercial Sensititre YeastOne TM (SYO) kit is widely used for antifungal susceptibility testing, but interpretive clinical breakpoints are not well defined. We determined echinocandins epidemiological cut-off values (ECV) for C. albicans/glabrata tested by SYO and assessed their ability to identify FKS mutants in a national survey of candidemia. Bloodstream isolates of C. albicans and C. glabrata were collected in 25 Swiss hospitals from 2004 to 2013 and tested by SYO. FKS hotspot sequencing was performed for isolates with a minimal inhibitory concentration (MIC) ≥ECV for any echinocandin. 1277 C. albicans and 347 C. glabrata were included. ECV 97.5% [μg/ml] of caspofungin, anidulafungin and micafungin were 0.12, 0.06, 0.03 for C. albicans, and 0.25, 0.12, 0.03 for C. glabrata. FKS hotspot sequencing was performed for 70 isolates. No mutation was found in the 52 "limit wild-type" isolates (MIC=ECV for ≥1 echinocandin). Among the 18 "non wild-type" isolates (MIC>ECV for ≥1 echinocandin), FKS mutations were recovered in the only two isolates with MIC>ECV for all 3 echinocandins, but not in those exhibiting a "non wild-type" phenotype for only one or two echinocandins. This 10-year nationwide survey showed that the rate of echinocandin resistance among C. albicans and C. glabrata remains low in Switzerland despite increased echinocandin use. SYO-ECV could discriminate FKS mutants from wild-type isolates tested by SYO in this population. Copyright © 2018. Published by Elsevier Ltd.

Production of White Colonies on CHROMagar Candida Medium by Members of the Candida glabrata Clade and Other Species with Overlapping Phenotypic Traits▿

PubMed Central

Bishop, Justin A.; Chase, Nancy; Lee, Richard; Kurtzman, Cletus P.; Merz, William G.

2008-01-01

We hypothesized that species of the Candida glabrata clade and species with phenotypic traits that overlap those of C. glabrata would produce white colonies on CHROMagar Candida medium. Of 154 isolates (seven species) tested, C. bracarensis, C. nivariensis, C. norvegensis, C. glabrata, and C. inconspicua produced white colonies; the Pichia fermentans group and C. krusei did not. Many of these species are difficult to identify phenotypically; white colonies may signal the need for the use of molecular approaches. PMID:18685009

Silver colloidal nanoparticles: antifungal effect against adhered cells and biofilms of Candida albicans and Candida glabrata.

PubMed

Monteiro, D R; Gorup, L F; Silva, S; Negri, M; de Camargo, E R; Oliveira, R; Barbosa, D B; Henriques, M

2011-08-01

The aim of this study was to evaluate the effect of silver nanoparticles (SN) against Candida albicans and Candida glabrata adhered cells and biofilms. SN (average diameter 5 nm) were synthesized by silver nitrate reduction with sodium citrate and stabilized with ammonia. Minimal inhibitory concentration (MIC) tests were performed for C. albicans (n = 2) and C. glabrata (n = 2) grown in suspension following the Clinical Laboratory Standards Institute microbroth dilution method. SN were applied to adhered cells (2 h) or biofilms (48 h) and after 24 h of contact their effect was assessed by enumeration of colony forming units (CFUs) and quantification of total biomass (by crystal violet staining). The MIC results showed that SN were fungicidal against all strains tested at very low concentrations (0.4-3.3 μg ml(-1)). Furthermore, SN were more effective in reducing biofilm biomass when applied to adhered cells (2 h) than to pre-formed biofilms (48 h), with the exception of C. glabrata ATCC, which in both cases showed a reduction ∼90%. Regarding cell viability, SN were highly effective on adhered C. glabrata and respective biofilms. On C. albicans the effect was not so evident but there was also a reduction in the number of viable biofilm cells. In summary, SN may have the potential to be an effective alternative to conventional antifungal agents for future therapies in Candida-associated denture stomatitis.

The oxidative stress response of the opportunistic fungal pathogen Candida glabrata.

PubMed

Briones-Martin-Del-Campo, Marcela; Orta-Zavalza, Emmanuel; Juarez-Cepeda, Jacqueline; Gutierrez-Escobedo, Guadalupe; Cañas-Villamar, Israel; Castaño, Irene; De Las Peñas, Alejandro

2014-01-01

Organisms have evolved different strategies to respond to oxidative stress generated as a by-product of aerobic respiration and thus maintain the redox homeostasis within the cell. In particular, fungal pathogens are exposed to reactive oxygen species (ROS) when they interact with the phagocytic cells of the host which are the first line of defense against fungal infections. These pathogens have co-opted the enzymatic (catalases, superoxide dismutases (SODs), and peroxidases) and non-enzymatic (glutathione) mechanisms used to maintain the redox homeostasis within the cell, to resist oxidative stress and ensure survival within the host. Several virulence factors have been related to the response to oxidative stress in pathogenic fungi. The opportunistic fungal pathogen Candida glabrata (C. glabrata) is the second most common cause of candidiasis after Candida albicans (C. albicans). C. glabrata has a well defined oxidative stress response (OSR), which include both enzymatic and non-enzymatic mechanisms. C. glabrata OSR is controlled by the well-conserved transcription factors Yap1, Skn7, Msn2 and Msn4. In this review, we describe the OSR of C. glabrata, what is known about its core elements, its regulation and how C. glabrata interacts with the host. This manuscript is part of the series of works presented at the "V International Workshop: Molecular genetic approaches to the study of human pathogenic fungi" (Oaxaca, Mexico, 2012). Copyright © 2013 Revista Iberoamericana de Micología. Published by Elsevier Espana. All rights reserved.

Candida glabrata's Genome Plasticity Confers a Unique Pattern of Expressed Cell Wall Proteins.

PubMed

López-Fuentes, Eunice; Gutiérrez-Escobedo, Guadalupe; Timmermans, Bea; Van Dijck, Patrick; De Las Peñas, Alejandro; Castaño, Irene

2018-06-05

Candida glabrata is the second most common cause of candidemia, and its ability to adhere to different host cell types, to microorganisms, and to medical devices are important virulence factors. Here, we consider three characteristics that confer extraordinary advantages to C. glabrata within the host. (1) C. glabrata has a large number of genes encoding for adhesins most of which are localized at subtelomeric regions. The number and sequence of these genes varies substantially depending on the strain, indicating that C. glabrata can tolerate high genomic plasticity; (2) The largest family of CWPs (cell wall proteins) is the EPA (epithelial adhesin) family of adhesins. Epa1 is the major adhesin and mediates adherence to epithelial, endothelial and immune cells. Several layers of regulation like subtelomeric silencing, cis- acting regulatory regions, activators, nutritional signaling, and stress conditions tightly regulate the expression of many adhesin-encoding genes in C. glabrata , while many others are not expressed. Importantly, there is a connection between acquired resistance to xenobiotics and increased adherence; (3) Other subfamilies of adhesins mediate adherence to Candida albicans , allowing C. glabrata to efficiently invade the oral epithelium and form robust biofilms. It is noteworthy that every C. glabrata strain analyzed presents a unique pattern of CWPs at the cell surface.

Rapid identification of drug resistant Candida species causing recurrent vulvovaginal candidiasis.

PubMed

Diba, Kambiz; Namaki, Atefeh; Ayatolahi, Haleh; Hanifian, Haleh

2012-01-01

Some yeast agents including Candida albicans, Candida tropicalis and Candida glabrata have a role in recurrent vulvovaginal candidiasis. We studied the frequency of both common and recurrent vulvovaginal candidiasis in symptomatic cases which were referred to Urmia Medical Sciences University related gynecology clinics using morphologic and molecular methods. The aim of this study was the identification of Candida species isolated from recurrent vulvovaginal candidiasis cases using a rapid and reliable molecular method. Vaginal swabs obtained from each case, were cultured on differential media including cornmeal agar and CHROM agar Candida. After 48 hours at 37℃, the cultures were studied for growth characteristics and color production respectively. All isolates were identified using the molecular method of PCR - restriction fragment length polymorphism. Among all clinical specimens, we detected 19 ( 16 % ) non fungal agents, 87 ( 82.1 % ) yeasts and 2 ( 1.9 % ) multiple infections. The yeast isolates identified morphologically included Candida albicans ( n = 62 ), Candida glabrata ( n = 9 ), Candida tropicalis ( n = 8 ), Candida parapsilosis ( n = 8 ) and Candida guilliermondii and Candida krusei ( n = 1 each ). We also obtained very similar results for Candida albicans, Candida glabrata and Candida tropicalis as the most common clinical isolates, by using PCR - Restriction Fragment Length Polymorphism. Use of two differential methods, morphologic and molecular, enabled us to identify most medically important Candida species which particularly cause recurrent vulvovaginal candidiasis.

Candida glabrata: an emerging oral opportunistic pathogen.

PubMed

Li, L; Redding, S; Dongari-Bagtzoglou, A

2007-03-01

Following the widespread use of immunosuppressive therapy and broad-spectrum antimycotic prophylaxis, C. glabrata has emerged as an important opportunistic pathogen in the oral mucosa. In the past, studies on the virulence factors and host-pathogen interactions of this organism were scarce, but continued to rise in recent years. Denture-wearing, immunosuppression, antibiotic therapy, and aging are risk factors for oral colonization or infection with C. glabrata. Compared with C. albicans, C. glabrata exhibits lower oral keratinocyte-adherence capacity, but higher denture-surface-adherence ability. The role of extracellular hydrolase production in the virulence of this organism does not appear to be as important as it is in C. albicans pathogenesis. Although traditionally thought of as a non-transforming yeast organism, both phenotypic switching and pseudohyphal formation have recently been identified in C. glabrata, but their role in pathogenesis is not known. With the exception of granulocyte monocyte colony-stimulating factor, C. glabrata triggers a lower proinflammatory cytokine response in oral epithelial cells than does C. albicans, in a strain-dependent manner. C. glabrata is less susceptible to killing by human beta-defensins than is C. albicans and exhibits various degrees of resistance to the antifungal activity of salivary histatins and mucins. In addition, C. glabrata possesses both innate and acquired resistance against antifungal drugs, due to its ability to modify ergosterol biosynthesis, mitochondrial function, or antifungal efflux. This resistance allows for its relative overgrowth over other susceptible species and may contribute to the recent emergence of C. glabrata infections in chronically immunocompromised populations. Further investigations on the virulence and host-pathogen interactions of C. glabrata are needed to better define the pathogenesis of oral C. glabrata infection in susceptible hosts.

Hichrom candida agar for identification of Candida species.

PubMed

Baradkar, V P; Mathur, M; Kumar, S

2010-01-01

Chromogenic media are frequently used in direct and rapid identification of yeasts because different Candida species produce unique colors on these media. We used 60 isolates of Candida species including 30 C. albicans, 10 C. parapsilosis, 11 C. glabrata, five C. tropicalis, and four C. dubliniensis, isolated from various clinical specimens, to evaluate the performance of HiChrome Candida agar. These strains had been identified by germ tube test, morphology on cornmeal agar, chlamydospore formation on tobacco agar and sugar assimilation tests. The sensitivity and specificity results were: C. albicans (96.55 and 96.42%); C. parapsilosis (80 and 98.03%), C. glabrata (90.90 and 88.23%), C. tropicalis (100 and 100%) and C. dubliniensis (60 and 96.55%) respectively. HiChrom Candida agaris medium has been useful and capable of presumptive, rapid identification of Candida species within 48 hours.

Dectin-1 plays an important role in host defense against systemic Candida glabrata infection.

PubMed

Chen, Si Min; Shen, Hui; Zhang, Teng; Huang, Xin; Liu, Xiao Qi; Guo, Shi Yu; Zhao, Jing Jun; Wang, Chun Fang; Yan, Lan; Xu, Guo Tong; Jiang, Yuan Ying; An, Mao Mao

2017-11-17

Candida glabrata is the second most common pathogen of severe candidiasis in immunocompromised hosts, following C. albicans. Although C. glabrata and C. albicans belong to the same genus, they are phylogenetically distinct. C-type lectin receptors (CLRs), acting as pattern-recognition receptors (PRRs), play critical roles in host defense against C. albicans infections. However, our understanding of the specific roles of CLRs in host defense against C. glabrata is limited. Here, we explored the potential roles of the C-type lectins Dectin-1 and Dectin-2 in host defense against C. glabrata. We found that both Dectin-1-deficient mice (Dectin-1 -/- ) and Dectin-2-deficient mice (Dectin-2 -/- ) are more susceptible to C. glabrata infection. Dectin-1confers host higher sensitivity for sensing C. glabrata infections, while the effect of Dectin-2 in the host defense against C. glabrata is infection dose dependent. Dectin-1 is required for host myeloid cells recognition, killing of C. glabrata, and development of subsequent Th1 and Th17 cell-mediated adaptive immune response. Significantly impaired inflammatory responses such as inflammatory cells recruitment and cytokines release that were induced by C. glabrata were manifested in Dectin-1-deficient mice. Together, our study demonstrates that Dectin-1 plays an important role in host defense against systemic Candida glabrata infections, indicating a previous unknown control mechanism for this particular type of infection in host. Our study, therefore, provides new insights into the host defense against C. glabrata.

[Opportunistic pathogen Candida glabrata and the mechanisms of its resistance to antifungal drugs].

PubMed

Berila, N; Subík, J

2010-04-01

Treatment of not only bacterial but also fungal infections is currently a growing concern. A major reason is the acquisition of multidrug resistance in both prokaryotic and human cells. The multidrug resistance phenotype is a cellular response to the presence of cytotoxic substances in the environment. The basic mechanism of multidrug resistance is overexpression of the membrane proteins involved in the extrusion of toxic substances outside the cell. The resistance mechanism based on the efflux of inhibitors as a result of the overproduction of transport proteins was also observed in some plant and animal pathogens and human tumour cells. The phenomenon of multidrug resistance associated with an excessive and long-term use of antifungals, in particular of azole derivatives, was also confirmed in the yeast Candida glabrata which is becoming a growing concern for health care professionals. Reduced susceptibility to azole derivatives in particular, a high potential for adapting to stressors, and multiple mechanisms of resistance to structurally and functionally unrelated antifungal drugs make the species C. glabrata a potential threat to hospital patients.

Susceptibility of Candida glabrata biofilms to echinocandins: alterations in the matrix composition.

PubMed

Rodrigues, Célia F; Rodrigues, Maria Elisa; Henriques, Mariana

2018-05-25

Candidiases are the most recurrent fungal infections, especially among immunosuppressed patients. Although Candida albicans is still the most widespread isolated species, non-Candida albicans Candida species have been increasing. The goal of this work was to determine the susceptibility of C. glabrata biofilms to echinocandins and to evaluate their effect on the biofilm matrix composition, comparing the results with other Candida species. Drug susceptibilities were assessed through the determination of minimum inhibitory concentration (MIC), minimum fungicidal concentration (MFC) and minimum biofilm eradication concentration (MBEC) of caspofungin (Csf) and micafugin (Mcf). The β-1,3 glucans content of the matrices was assessed after contact with the drugs. The data suggest that, generally, after contact with echinocandins, the concentration of β-1,3 glucans increased. These adjustments in the matrix composition of C. glabrata biofilms and the chemical differences between Csf and Mcf, seem responsible and may determine the effectivity of the drug responses.

Fluconazole affects the alkali-metal-cation homeostasis and susceptibility to cationic toxic compounds of Candida glabrata.

PubMed

Elicharova, Hana; Sychrova, Hana

2014-08-01

Candida glabrata is a salt-tolerant and fluconazole (FLC)-resistant yeast species. Here, we analyse the contribution of plasma-membrane alkali-metal-cation exporters, a cation/proton antiporter and a cation ATPase to cation homeostasis and the maintenance of membrane potential (ΔΨ). Using a series of single and double mutants lacking CNH1 and/or ENA1 genes we show that the inability to export potassium and toxic alkali-metal cations leads to a slight hyperpolarization of the plasma membrane of C. glabrata cells; this hyperpolarization drives more cations into the cells and affects cation homeostasis. Surprisingly, a much higher hyperpolarization of C. glabrata plasma membrane was produced by incubating cells with subinhibitory concentrations of FLC. FLC treatment resulted in a substantially increased sensitivity of cells to various cationic drugs and toxic cations that are driven into the cell by negative-inside plasma-membrane potential. The effect of the combination of FLC plus cationic drug treatment was enhanced by the malfunction of alkali-metal-cation transporters that contribute to the regulation of membrane potential and cation homeostasis. In summary, we show that the combination of subinhibitory concentrations of FLC and cationic drugs strongly affects the growth of C. glabrata cells. © 2014 The Authors.

Candida glabrata species complex prevalence and antifungal susceptibility testing in a culture collection: First description of Candida nivariensis in Argentina.

PubMed

Morales-López, Soraya Eugenia; Taverna, Constanza G; Bosco-Borgeat, María Eugenia; Maldonado, Ivana; Vivot, Walter; Szusz, Wanda; Garcia-Effron, Guillermo; Córdoba, Susana B

2016-12-01

The presence of the cryptic species belonging to the Candida glabrata complex has not been studied in Argentina. We analyzed a collection of 117 clinical isolates of C. glabrata complex belonging to a National Culture Collection of Instituto Nacional de Microbiología "Dr. Carlos G. Malbrán" from Argentina (40 isolates from blood samples, 18 from other normally sterile sites, 20 from vagina, 14 from urine, 7 from oral cavity, 3 from catheter, 1 from a stool sample and 14 isolates whose clinical origin was not recorded). The aims of this work were to determine the prevalence of the cryptic species Candida nivariensis and Candida bracarensis and to evaluate the susceptibility profile of isolates against nine antifungal drugs. Identification was carried out by using classical phenotypic tests, CHROMagar™ Candida, PCR and MALDI-TOF. The minimal inhibitory concentrations of amphotericin B, 5-fluorocytosine, fluconazole, itraconazole, voriconazole, ketoconazole, posaconazole, caspofungin and anidulafungin were determined according to the EDef 7.3 (EUCAST) reference document. Of the 117 isolates, 114 were identified as C. glabrata and three as C. nivariensis by using PCR and MALDI-TOF. There were no major differences between C. nivariensis and C. glabrata susceptibility profiles. No resistant strains were found to echinocandins. We have found that the percentage of C. nivariensis in our culture collection was 2.56. This is the first description of C. nivariensis in Argentina, and data obtained could contribute to the knowledge of the epidemiology of this cryptic species.

Relationships between Respiration and Susceptibility to Azole Antifungals in Candida glabrata

PubMed Central

Brun, Sophie; Aubry, Christophe; Lima, Osana; Filmon, Robert; Bergès, Thierry; Chabasse, Dominique; Bouchara, Jean-Philippe

2003-01-01

Over the past two decades, the incidence of infections due to Candida glabrata, a yeast with intrinsic low susceptibility to azole antifungals, has increased markedly. Respiratory deficiency due to mutations in mitochondrial DNA (mtDNA) associated with resistance to azoles frequently occurs in vitro in this species. In order to specify the relationships between respiration and azole susceptibility, the effects of respiratory chain inhibitors on a wild-type isolate of C. glabrata were evaluated. Respiration of blastoconidia was immediately blocked after extemporaneous addition of potassium cyanide, whereas a 4-h preincubation was required for sodium azide. Antifungal susceptibility determined by a disk diffusion method on Casitone agar containing sodium azide showed a significant decrease in the susceptibility to azoles. Biweekly subculturing on Casitone agar supplemented with sodium azide was therefore performed. This resulted after 40 passages in the isolation of a respiration-deficient mutant, as suggested by its lack of growth on glycerol-containing agar. This respiratory deficiency was confirmed by flow cytometric analysis of blastoconidia stained with rhodamine 123 and by oxygraphy. Moreover, transmission electron microscopy and restriction endonuclease analysis of the mtDNA of mutant cells demonstrated the mitochondrial origin of the respiratory deficiency. Finally, this mutant exhibited cross-resistance to all the azoles tested. In conclusion, blockage of respiration in C. glabrata induces decreased susceptibility to azoles, culminating in azole resistance due to the deletion of mtDNA. This mechanism could explain the induction of petite mutations by azole antifungals which have been demonstrated to act directly on the mitochondrial respiratory chain. PMID:12604511

Interactions between Candida albicans and Candida glabrata in biofilms: Influence of the strain type, culture medium and glucose supplementation.

PubMed

Hosida, Thayse Yumi; Cavazana, Thamires Priscila; Henriques, Mariana; Pessan, Juliano Pelim; Delbem, Alberto Carlos Botazzo; Monteiro, Douglas Roberto

2018-04-01

The relationship among Candida species may be influenced by several factors. Thus, this study evaluated the interactions between Candida albicans and Candida glabrata in biofilms, varying the strain type, culture medium and glucose supplementation. Biofilms were formed for 48 hours in Sabouraud dextrose broth (SDB) or RPMI 1640, supplemented with 0%, 1% or 5% glucose. Each strain of C. albicans was combined with two strains of C. glabrata, generating four biofilm associations, which were quantified by colony-forming units (CFUs), total biomass and metabolic activity. Data were analysed by ANOVA and Tukey's HSD test (α = 0.05). For CFUs, all associations were classified as indifferent for biofilms formed in RPMI 1640, while for SDB the interactions were antagonistic for C. albicans and indifferent for C. glabrata. The association of reference strains resulted in a dual-species biofilm with biomass significantly higher than that observed for each single biofilm developed in SDB. The metabolic activity of dual-species biofilms did not significantly differ from that found for single ones, except for co-culture of the reference strains. Glucose supplementation and culture media had a significant influence on all parameters. In conclusion, the strain type, culture medium and glucose supplementation influenced the interactions between C. albicans and C. glabrata. © 2017 Blackwell Verlag GmbH.

Discriminative power of fatty acid methyl ester (FAME) analysis using the microbial identification system (MIS) for Candida (Torulopsis) glabrata and Saccharomyces cerevisiae.

PubMed

Peltroche-Llacsahuanga, H; Schmidt, S; Lütticken, R; Haase, G

2000-12-01

Candida (Torulopsis) glabrata is frequently isolated in cases of fungal infection and commonly shows acquired or innate fluconazole resistance. Saccharomyces cerevisiae, an emerging opportunistic yeast pathogen, causes serious systemic infections in immunocompromised, and vaginitis and superficial infections in immunocompetent patients. For both species reliable identification in the routine laboratory is mandatory, but species identification of strains, e.g. trehalose-negative C. glabrata, may be difficult. Therefore, gas-liquid chromatography (GLC) of whole cell fatty acid methyl ester (FAME) profiles, that is independent of assimilation profiles of strains and suitable for reliable and rapid identification of clinically important yeasts, was applied. However, frequent misidentification of C. glabrata as S. cerevisiae has been reported when using the Yeast Clinical Database of MIS. Accuracy of MIS identification may be strongly influenced by the amounts of cell mass analyzed. Therefore, the present study compared the MIS results of these two yeasts achieved with different cell masses. Primarily we optimized, especially with respect to cost-effectiveness, the recommended streaking technique yielding a maximal recovery of 90-130 mg of cell mass from one plate, enabling testing of poor growing strains of C. glabrata. For all C. glabrata strains tested (n = 10) the highest identification scores (SI [Similarity Index] range 0.525-0.963, median 0.832) were achieved with 30 to 45 mg of cell mass. Only 5 of 10 S. cerevisiae strains revealed good library comparisons (SI > or = 0.5) when using 30 mg of cell mass, whereas with 45 mg all strains but two revealed this SI-level. For S. cerevisiae a higher amount of cell mass processed (up to 90 mg) was correlated with better identification scores (SI range using 90 mg: 0.464-0.870, median, 0.737). Several passages prior to FAME analysis of C. glabrata strains on recommended media revealed narrowing of SI ranges, but

Atomic structure of the nuclear pore complex targeting domain of a Nup116 homologue from the yeast, Candida glabrata

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sampathkumar, Parthasarathy; Kim, Seung Joong; Manglicmot, Danalyn

2012-10-23

The nuclear pore complex (NPC), embedded in the nuclear envelope, is a large, dynamic molecular assembly that facilitates exchange of macromolecules between the nucleus and the cytoplasm. The yeast NPC is an eightfold symmetric annular structure composed of {approx}456 polypeptide chains contributed by {approx}30 distinct proteins termed nucleoporins. Nup116, identified only in fungi, plays a central role in both protein import and mRNA export through the NPC. Nup116 is a modular protein with N-terminal 'FG' repeats containing a Gle2p-binding sequence motif and a NPC targeting domain at its C-terminus. We report the crystal structure of the NPC targeting domain ofmore » Candida glabrata Nup116, consisting of residues 882-1034 [CgNup116(882-1034)], at 1.94 {angstrom} resolution. The X-ray structure of CgNup116(882-1034) is consistent with the molecular envelope determined in solution by small-angle X-ray scattering. Structural similarities of CgNup116(882-1034) with homologous domains from Saccharomyces cerevisiae Nup116, S. cerevisiae Nup145N, and human Nup98 are discussed.« less

Proteomic analysis of hyperadhesive Candida glabrata clinical isolates reveals a core wall proteome and differential incorporation of adhesins.

PubMed

Gómez-Molero, Emilia; de Boer, Albert D; Dekker, Henk L; Moreno-Martínez, Ana; Kraneveld, Eef A; Ichsan; Chauhan, Neeraj; Weig, Michael; de Soet, Johannes J; de Koster, Chris G; Bader, Oliver; de Groot, Piet W J

2015-12-01

Attachment to human host tissues or abiotic medical devices is a key step in the development of infections by Candida glabrata. The genome of this pathogenic yeast codes for a large number of adhesins, but proteomic work using reference strains has shown incorporation of only few adhesins in the cell wall. By making inventories of the wall proteomes of hyperadhesive clinical isolates and reference strain CBS138 using mass spectrometry, we describe the cell wall proteome of C. glabrata and tested the hypothesis that hyperadhesive isolates display differential incorporation of adhesins. Two clinical strains (PEU382 and PEU427) were selected, which both were hyperadhesive to polystyrene and showed high surface hydrophobicity. Cell wall proteome analysis under biofilm-forming conditions identified a core proteome of about 20 proteins present in all C. glabrata strains. In addition, 12 adhesin-like wall proteins were identified in the hyperadherent strains, including six novel adhesins (Awp8-13) of which only Awp12 was also present in CBS138. We conclude that the hyperadhesive capacity of these two clinical C. glabrata isolates is correlated with increased and differential incorporation of cell wall adhesins. Future studies should elucidate the role of the identified proteins in the establishment of C. glabrata infections. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Epidemiology and antifungal susceptibilities of yeast isolates causing invasive infections across urban Beijing, China.

PubMed

Guo, Li-Na; Xiao, Meng; Cao, Bin; Qu, Fen; Zhan, Yu-Liang; Hu, Yun-Jian; Wang, Xin-Ru; Liang, Guo-Wei; Gu, Hai-Tong; Qi, Jun; Yuan, Hui; Min, Rong; Wang, Fei-Yan; Liu, Lin-Juan; Wang, Hai-Bin; Jiang, Wei; Duan, Xue-Guang; Xu, Wen-Jian; Yu, Yan-Hua; Su, Jian-Rong; Zhang, Jian-Zhong; Nong, Jin-Qing; Liu, Shu-Mei; Li, Jun; Liu, Jun-Ting; Yue, Zhi-Gang; Yang, Duo; Guo, Jie; Zhao, Rui; Zhang, Ya-Nan; Yang, Xi-Ming; Liu, Xiao-Qing; Hsueh, Po-Ren; Xu, Ying-Chun

2017-09-01

To investigate the species distribution and antifungal susceptibility profiles of yeast isolates causing invasive infections across Beijing. A total of 1201 yeast isolates recovered from blood and other sterile body fluids were correctly identified by matrix-assisted laser desorption/ionization TOF MS supplemented by DNA sequencing. Antifungal susceptibility testing was performed according to the Clinical and Laboratory Standards Institute broth microdilution method. Candida (95.5%) remained the most common yeast species isolated; Candida albicans (38.8%) and Candida parapsilosis (22.6%) were the leading species of candidemia. Azole resistances were mainly observed in Candida glabrata and Candida tropicalis isolates. This study outlined the epidemiologic data of invasive yeast infections and highlighted the need for continuous monitoring of azole resistances among C. glabrata and C. tropicalis isolates in Beijing.

Development of an In Vitro Model for the Multi-Parametric Quantification of the Cellular Interactions between Candida Yeasts and Phagocytes

PubMed Central

Noël, Thierry

2012-01-01

We developed a new in vitro model for a multi-parameter characterization of the time course interaction of Candida fungal cells with J774 murine macrophages and human neutrophils, based on the use of combined microscopy, fluorometry, flow cytometry and viability assays. Using fluorochromes specific to phagocytes and yeasts, we could accurately quantify various parameters simultaneously in a single infection experiment: at the individual cell level, we measured the association of phagocytes to fungal cells and phagocyte survival, and monitored in parallel the overall phagocytosis process by measuring the part of ingested fungal cells among the total fungal biomass that changed over time. Candida albicans, C. glabrata, and C. lusitaniae were used as a proof of concept: they exhibited species-specific differences in their association rate with phagocytes. The fungal biomass uptaken by the phagocytes differed significantly according to the Candida species. The measure of the survival of fungal and immune cells during the interaction showed that C. albicans was the more aggressive yeast in vitro, destroying the vast majority of the phagocytes within five hours. All three species of Candida were able to survive and to escape macrophage phagocytosis either by the intraphagocytic yeast-to-hyphae transition (C. albicans) and the fungal cell multiplication until phagocytes burst (C. glabrata, C. lusitaniae), or by the avoidance of phagocytosis (C. lusitaniae). We demonstrated that our model was sensitive enough to quantify small variations of the parameters of the interaction. The method has been conceived to be amenable to the high-throughput screening of mutants in order to unravel the molecular mechanisms involved in the interaction between yeasts and host phagocytes. PMID:22479332

Comparative Study of the Effects of Fluconazole and Voriconazole on Candida glabrata, Candida parapsilosis and Candida rugosa Biofilms.

PubMed

Madhavan, Priya; Jamal, Farida; Pei, Chong Pei; Othman, Fauziah; Karunanidhi, Arunkumar; Ng, Kee Peng

2018-06-01

Infections by non-albicans Candida species are a life-threatening condition, and formation of biofilms can lead to treatment failure in a clinical setting. This study was aimed to demonstrate the in vitro antibiofilm activity of fluconazole (FLU) and voriconazole (VOR) against C. glabrata, C. parapsilosis and C. rugosa with diverse antifungal susceptibilities to FLU and VOR. The antibiofilm activities of FLU and VOR in the form of suspension as well as pre-coatings were assessed by XTT [2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide] reduction assay. Morphological and intracellular changes exerted by the antifungal drugs on Candida cells were examined by scanning electron microscope (SEM) and transmission electron microscope (TEM). The results of the antibiofilm activities showed that FLU drug suspension was capable of killing C. parapsilosis and C. rugosa at minimum inhibitory concentrations (MICs) of 4× MIC FLU and 256× MIC FLU, respectively. While VOR MICs ranging from 2× to 32× were capable of killing the biofilms of all Candida spp tested. The antibiofilm activities of pre-coated FLU were able to kill the biofilms at ¼× MIC FLU and ½× MIC FLU for C. parapsilosis and C. rugosa strains, respectively. While pre-coated VOR was able to kill the biofilms, all three Candida sp at ½× MIC VOR. SEM and TEM examinations showed that FLU and VOR treatments exerted significant impact on Candida cell with various degrees of morphological changes. In conclusion, a fourfold reduction in MIC 50 of FLU and VOR towards ATCC strains of C. glabrata, C. rugosa and C. rugosa clinical strain was observed in this study.

Structure-Guided Development of Efficacious Antifungal Agents Targeting Candida Glabrata Dihydrofolate Reductase

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, J.; Bolstad, D; Smith, A

2008-01-01

Candida glabrata is a lethal fungal pathogen resistant to many antifungal agents and has emerged as a critical target for drug discovery. Over the past several years, we have been developing a class of propargyl-linked antifolates as antimicrobials and hypothesized that these compounds could be effective inhibitors of dihydrofolate reductase (DHFR) from C. glabrata. We initially screened a small collection of these inhibitors and found modest levels of potency. Subsequently, we determined the crystal structure of C. glabrata DHFR bound to a representative inhibitor with data to 1.6 A resolution. Using this structure, we designed and synthesized second-generation inhibitors. Thesemore » inhibitors bind the C. glabrata DHFR enzyme with subnanomolar potency, display greater than 2000-fold levels of selectivity over the human enzyme, and inhibit the growth of C. glabrata at levels observed with clinically employed therapeutics.« less

Reversal of fluconazole resistance induced by a synergistic effect with Acca sellowiana in Candida glabrata strains.

PubMed

R M Machado, Gabriella da; Pippi, Bruna; Dalla Lana, Daiane Flores; Amaral, Ana Paula S; Teixeira, Mário Lettieri; Souza, Kellen C B de; Fuentefria, Alexandre M

2016-11-01

The increased incidence of non-albicans Candida (NAC) resistant to fluconazole (FLZ) makes it necessary to use new therapeutic alternatives. Acca sellowiana (O.berg) Burret (Myrtaceae) is a guava with several proven biological activities. The interaction with fluconazole can be a feasible alternative to overcome this resistance. This study evaluates the in vitro antifungal activity of fractions obtained from the lyophilized aqueous extract of the leaves of A. sellowiana against resistant strains of NAC. The antifungal activity of the fractions was evaluated at 500 μg/mL by microdilution method. Checkerboard assay was performed to determine the effect of the combination of the F2 fraction and antifungal at concentrations: MIC/4, MIC/2, MIC, MIC × 2 and MIC × 4. Candida glabrata showed the lowest MIC values (500-3.90 μg/mL) and the F2 active fraction was the most effective. The association of F2 with FLZ showed a strong synergistic effect (FICI ≤ 0.5) against 100% of C. glabrata resistant isolates. Moreover, the F2 active fraction has demonstrated that probably acts in the cell wall of these yeasts. There was no observed acute dermal toxicity of lyophilized aqueous extract of leaves of A. sellowiana on pig ear skin cells. The interaction between substances present in the F2 active fraction is possibly responsible for the antifungal activity presented by this fraction. This study is unprecedented and suggests that the combination of F2 active fraction and FLZ might be used as an alternative treatment for mucocutaneus infections caused by C. glabrata resistant.

Synergistic anticandidal activity of menthol in combination with itraconazole and nystatin against clinical Candida glabrata and Candida krusei isolates.

PubMed

Sharifzadeh, Aghil; Khosravi, Ali Reza; Shokri, Hojjatollah; Tari, Paria Samadi

2017-06-01

Candida glabrata (C. glabrata) and C. krusei are now emerging as serious hospital acquired infections in immunocompromised patients. Menthol, a terpenic compound, has been reported to have antifungal activity. The aim of this study was to investigate the effect of menthol in combination with itraconazole or nystatin against C. glabrata and C. krusei isolates. The effects of menthol along with itraconazole and nystatin, were evaluated by the Clinical Laboratory Standards Institute (CLSI) M44-A and CLSI M27-A3 methods. The fractional inhibitory concentration index (FICI) was determined for menthol plus itraconazole and nystatin combinations using the checkerboard method. The mean of minimum inhibitory concentration (MIC) values of menthol, nystatin and itraconazole were 53.2, 2.30 and 1.50 μg/ml for C. glabrata isolates and 121, 1.08 and 0.38 μg/ml for C. krusei isolates, respectively. Menthol in combination with itraconazole or nystatin exhibited the synergistic effects against all species of Candida tested. FICI values for menthol plus itraconazole and nystatin combinations ranged from 0.250 to 0.561 and 0.139 to 0.623 for C. glabrata isolates, and 0.182 to 0.750 and 0.188 to 0.760 for C. krusei, respectively. These results support the potential use of menthol as an anticandidal agent, and it can be used complementarily with other conventional antifungal agents. Copyright © 2017. Published by Elsevier Ltd.

[Prevalence of vaginal candidiasis in pregnant women. Identification of yeasts and susceptibility to antifungal agents].

PubMed

García Heredia, M; García, S D; Copolillo, E F; Cora Eliseth, M; Barata, A D; Vay, C A; de Torres, R A; Tiraboschi, N; Famiglietti, A M R

2006-01-01

Pregnant women are more susceptible to both vaginal colonization and infection by yeast. Our objectives were to determine the prevalence in pregnant women of yeasts isolated from vaginal exudates and their susceptibility to current antifungal drugs. A total of 493 patients was studied between December 1998 and February 2000. The prevalence of Candida spp. was 28% (Candida albicans 90.4%; Candida glabrata 6.3%; Candida parapsilosis 1.1%, Candida kefyr 1.1 %; unidentified species 1.1 %). The diffusion test in Shadomy agar was employed to determine the susceptibility to fluconazole, ketoconazole, itraconazole and nistatine. All C. albicans, C. kefyr and C. parapsilosis isolates were susceptible in vitro to the antifungal agents tested, while 1 in 6 C. glabrata isolates showed resistance to azole drugs; all strains were susceptible to nistatine. In pregnant women, C. albicans was the yeast most frequently isolated from vaginal exudates; it continues to be highly susceptible to antifungal drugs. Azole resistance was detected only among C. glabrata isolates. Identification to the species level is recommended, specially in cases of treatment failure and recurrent or chronic infection.

Generational distribution of a Candida glabrata population: Resilient old cells prevail, while younger cells dominate in the vulnerable host.

PubMed

Bouklas, Tejas; Alonso-Crisóstomo, Luz; Székely, Tamás; Diago-Navarro, Elizabeth; Orner, Erika P; Smith, Kalie; Munshi, Mansa A; Del Poeta, Maurizio; Balázsi, Gábor; Fries, Bettina C

2017-05-01

Similar to other yeasts, the human pathogen Candida glabrata ages when it undergoes asymmetric, finite cell divisions, which determines its replicative lifespan. We sought to investigate if and how aging changes resilience of C. glabrata populations in the host environment. Our data demonstrate that old C. glabrata are more resistant to hydrogen peroxide and neutrophil killing, whereas young cells adhere better to epithelial cell layers. Consequently, virulence of old compared to younger C. glabrata cells is enhanced in the Galleria mellonella infection model. Electron microscopy images of old C. glabrata cells indicate a marked increase in cell wall thickness. Comparison of transcriptomes of old and young C. glabrata cells reveals differential regulation of ergosterol and Hog pathway associated genes as well as adhesion proteins, and suggests that aging is accompanied by remodeling of the fungal cell wall. Biochemical analysis supports this conclusion as older cells exhibit a qualitatively different lipid composition, leading to the observed increased emergence of fluconazole resistance when grown in the presence of fluconazole selection pressure. Older C. glabrata cells accumulate during murine and human infection, which is statistically unlikely without very strong selection. Therefore, we tested the hypothesis that neutrophils constitute the predominant selection pressure in vivo. When we altered experimentally the selection pressure by antibody-mediated removal of neutrophils, we observed a significantly younger pathogen population in mice. Mathematical modeling confirmed that differential selection of older cells is sufficient to cause the observed demographic shift in the fungal population. Hence our data support the concept that pathogenesis is affected by the generational age distribution of the infecting C. glabrata population in a host. We conclude that replicative aging constitutes an emerging trait, which is selected by the host and may even play an

Acquired Flucytosine Resistance during Combination Therapy with Caspofungin and Flucytosine for Candida glabrata Cystitis

PubMed Central

El Sissy, Carine; Bachelier-Bassi, Sophie; Scemla, Anne; Quesne, Gilles; Sitterlé, Emilie; Legendre, Christophe; Lortholary, Olivier; Bougnoux, Marie-Elisabeth

2015-01-01

Treatment of Candida glabrata cystitis remains a therapeutic challenge, and an antifungal combination using flucytosine is one option. We describe two patients with refractory C. glabrata cystitis who failed flucytosine combined with caspofungin with early-acquired high-level resistance to flucytosine due to nonsense mutations in the FUR1 gene. Rapidly acquired flucytosine resistance with microbiological failure should discourage combination of caspofungin and flucytosine during urinary candidiasis. PMID:26525799

Med15B Regulates Acid Stress Response and Tolerance in Candida glabrata by Altering Membrane Lipid Composition

PubMed Central

Qi, Yanli; Liu, Hui; Yu, Jiayin; Chen, Xiulai

2017-01-01

ABSTRACT Candida glabrata is a promising producer of organic acids. To elucidate the physiological function of the Mediator tail subunit Med15B in the response to low-pH stress, we constructed a deletion strain, C. glabrata med15BΔ, and an overexpression strain, C. glabrata HTUΔ/CgMED15B. Deletion of MED15B caused biomass production, glucose consumption rate, and cell viability to decrease by 28.3%, 31.7%, and 26.5%, respectively, compared with those of the parent (HTUΔ) strain at pH 2.0. Expression of lipid metabolism-related genes was significantly downregulated in the med15BΔ strain, whereas key genes of ergosterol biosynthesis showed abnormal upregulation. This caused the proportion of C18:1 fatty acids, the ratio of unsaturated to saturated fatty acids (UFA/SFA), and the total phospholipid content to decrease by 11.6%, 27.4%, and 37.6%, respectively. Cells failed to synthesize fecosterol and ergosterol, leading to the accumulation and a 60.3-fold increase in the concentration of zymosterol. Additionally, cells showed reductions of 69.2%, 11.6%, and 21.8% in membrane integrity, fluidity, and H+-ATPase activity, respectively. In contrast, overexpression of Med15B increased the C18:1 levels, total phospholipids, ergosterol content, and UFA/SFA by 18.6%, 143.5%, 94.5%, and 18.7%, respectively. Membrane integrity, fluidity, and H+-ATPase activity also increased by 30.2%, 6.9%, and 51.8%, respectively. Furthermore, in the absence of pH buffering, dry weight of cells and pyruvate concentrations were 29.3% and 61.2% higher, respectively, than those of the parent strain. These results indicated that in C. glabrata, Med15B regulates tolerance toward low pH via transcriptional regulation of acid stress response genes and alteration in lipid composition. IMPORTANCE This study explored the role of the Mediator tail subunit Med15B in the metabolism of Candida glabrata under acidic conditions. Overexpression of MED15B enhanced yeast tolerance to low pH and improved

[Yeast species in vulvovaginitis candidosa].

PubMed

Nemes-Nikodém, Éva; Tamási, Béla; Mihalik, Noémi; Ostorházi, Eszter

2015-01-04

Vulvovaginal candidiasis is the most common mycosis, however, the available information about antifungal susceptibilities of these yeasts is limited. To compare the gold standard fungal culture with a new molecular identification method and report the incidence of yeast species in vulvovaginitis candidosa. The authors studied 370 yeasts isolated from vulvovaginal candidiasis and identified them by phenotypic and molecular methods. The most common species was Candida albicans (85%), followed by Candida glabrata, and other Candida species. At present there are no recommendations for the evaluation of antifungal susceptibility of pathogenic fungal species occurring in vulvovaginal candidiasis and the natural antifungal resistance of the different species is known only. Matrix Assisted Laser Desorption Ionization Time of Flight identification can be used to differentiate the fluconazole resistant Candida dubliniensis and the sensitive Candida albicans strains.

Acquired Flucytosine Resistance during Combination Therapy with Caspofungin and Flucytosine for Candida glabrata Cystitis.

PubMed

Charlier, Caroline; El Sissy, Carine; Bachelier-Bassi, Sophie; Scemla, Anne; Quesne, Gilles; Sitterlé, Emilie; Legendre, Christophe; Lortholary, Olivier; Bougnoux, Marie-Elisabeth

2016-01-01

Treatment of Candida glabrata cystitis remains a therapeutic challenge, and an antifungal combination using flucytosine is one option. We describe two patients with refractory C. glabrata cystitis who failed flucytosine combined with caspofungin with early-acquired high-level resistance to flucytosine due to nonsense mutations in the FUR1 gene. Rapidly acquired flucytosine resistance with microbiological failure should discourage combination of caspofungin and flucytosine during urinary candidiasis. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Engineering of carboligase activity reaction in Candida glabrata for acetoin production.

PubMed

Li, Shubo; Xu, Nan; Liu, Liming; Chen, Jian

2014-03-01

Utilization of Candida glabrata overproducing pyruvate is a promising strategy for high-level acetoin production. Based on the known regulatory and metabolic information, acetaldehyde and thiamine were fed to identify the key nodes of carboligase activity reaction (CAR) pathway and provide a direction for engineering C. glabrata. Accordingly, alcohol dehydrogenase, acetaldehyde dehydrogenase, pyruvate decarboxylase, and butanediol dehydrogenase were selected to be manipulated for strengthening the CAR pathway. Following the rational metabolic engineering, the engineered strain exhibited increased acetoin biosynthesis (2.24 g/L). In addition, through in silico simulation and redox balance analysis, NADH was identified as the key factor restricting higher acetoin production. Correspondingly, after introduction of NADH oxidase, the final acetoin production was further increased to 7.33 g/L. By combining the rational metabolic engineering and cofactor engineering, the acetoin-producing C. glabrata was improved stepwise, opening a novel pathway for rational development of microorganisms for bioproduction. Copyright © 2013. Published by Elsevier Inc.

Aspartyl proteases in Candida glabrata are required for suppression of the host innate immune response.

PubMed

Rasheed, Mubashshir; Battu, Anamika; Kaur, Rupinder

2018-04-27

A family of 11 cell surface-associated aspartyl proteases (CgYps1-11), also referred as yapsins, is a key virulence factor in the pathogenic yeast Candida glabrata However, the mechanism by which CgYapsins modulate immune response and facilitate survival in the mammalian host remains to be identified. Here, using RNA-Seq analysis, we report that genes involved in cell wall metabolism are differentially regulated in the Cgyps1-11 Δ mutant. Consistently, the mutant contained lower β-glucan and mannan levels and exhibited increased chitin content in the cell wall. As cell wall components are known to regulate the innate immune response, we next determined the macrophage transcriptional response to C. glabrata infection and observed differential expression of genes implicated in inflammation, chemotaxis, ion transport, and the tumor necrosis factor signaling cascade. Importantly, the Cgyps1-11 Δ mutant evoked a different immune response, resulting in an enhanced release of the pro-inflammatory cytokine IL-1β in THP-1 macrophages. Further, Cgyps1-11 Δ-induced IL-1β production adversely affected intracellular proliferation of co-infected WT cells and depended on activation of spleen tyrosine kinase (Syk) signaling in the host cells. Accordingly, the Syk inhibitor R406 augmented intracellular survival of the Cgyps1-11 Δ mutant. Finally, we demonstrate that C. glabrata infection triggers elevated IL-1β production in mouse organs and that the CgYPS genes are required for organ colonization and dissemination in the murine model of systemic infection. Altogether, our results uncover the basis for macrophage-mediated killing of Cgyps1-11 Δ cells and provide the first evidence that aspartyl proteases in C. glabrata are required for suppression of IL-1β production in macrophages. © 2018 by The American Society for Biochemistry and Molecular Biology, Inc.

Aspartyl proteases in Candida glabrata are required for suppression of the host innate immune response

PubMed Central

Rasheed, Mubashshir; Battu, Anamika; Kaur, Rupinder

2018-01-01

A family of 11 cell surface-associated aspartyl proteases (CgYps1–11), also referred as yapsins, is a key virulence factor in the pathogenic yeast Candida glabrata. However, the mechanism by which CgYapsins modulate immune response and facilitate survival in the mammalian host remains to be identified. Here, using RNA-Seq analysis, we report that genes involved in cell wall metabolism are differentially regulated in the Cgyps1–11Δ mutant. Consistently, the mutant contained lower β-glucan and mannan levels and exhibited increased chitin content in the cell wall. As cell wall components are known to regulate the innate immune response, we next determined the macrophage transcriptional response to C. glabrata infection and observed differential expression of genes implicated in inflammation, chemotaxis, ion transport, and the tumor necrosis factor signaling cascade. Importantly, the Cgyps1–11Δ mutant evoked a different immune response, resulting in an enhanced release of the pro-inflammatory cytokine IL-1β in THP-1 macrophages. Further, Cgyps1–11Δ–induced IL-1β production adversely affected intracellular proliferation of co-infected WT cells and depended on activation of spleen tyrosine kinase (Syk) signaling in the host cells. Accordingly, the Syk inhibitor R406 augmented intracellular survival of the Cgyps1–11Δ mutant. Finally, we demonstrate that C. glabrata infection triggers elevated IL-1β production in mouse organs and that the CgYPS genes are required for organ colonization and dissemination in the murine model of systemic infection. Altogether, our results uncover the basis for macrophage-mediated killing of Cgyps1–11Δ cells and provide the first evidence that aspartyl proteases in C. glabrata are required for suppression of IL-1β production in macrophages. PMID:29491142

In Vitro Activities of Terbinafine against Cutaneous Isolates of Candida albicans and Other Pathogenic Yeasts

PubMed Central

Ryder, Neil S.; Wagner, Sonja; Leitner, Ingrid

1998-01-01

Terbinafine is active in vitro against a wide range of pathogenic fungi, including dermatophytes, molds, dimorphic fungi, and some yeasts, but earlier studies indicated that the drug had little activity against Candida albicans. In contrast, clinical studies have shown topical and oral terbinafine to be active in cutaneous candidiasis and Candida nail infections. In order to define the anti-Candida activity of terbinafine, we tested the drug against 350 fresh clinical isolates and additional strains by using a broth dilution assay standardized according to the guidelines of the National Committee for Clinical Laboratory Standards (NCCLS) M27-A assay. Terbinafine was found to have an MIC of 1 μg/ml for reference C. albicans strains. For 259 clinical isolates, the MIC at which 50% of the isolates are inhibited (MIC50) of terbinafine was 1 μg/ml (fluconazole, 0.5 μg/ml), and the MIC90 was 4 μg/ml (fluconazole, 1 μg/ml). Terbinafine was highly active against Candida parapsilosis (MIC90, 0.125 μg/ml) and showed potentially interesting activity against isolates of Candida dubliniensis, Candida guilliermondii, Candida humicola, and Candida lusitaniae. It was not active against the Candida glabrata, Candida krusei, and Candida tropicalis isolates in this assay. Cryptococcus laurentii and Cryptococcus neoformans were highly susceptible to terbinafine, with MICs of 0.06 to 0.25 μg/ml. The NCCLS macrodilution assay provides reproducible in vitro data for terbinafine against Candida and other yeasts. The MICs for C. albicans and C. parapsilosis are compatible with the known clinical efficacy of terbinafine in cutaneous infections, while the clinical relevance of its activities against the other species has yet to be determined. PMID:9593126

Drug susceptibility profile of Candida glabrata clinical isolates from Iran and genetic resistant mechanisms to caspofungin.

PubMed

Amanloo, Saeid; Shams-Ghahfarokhi, Masoomeh; Ghahri, Mohammad; Razzaghi-Abyaneh, Mehdi

2018-04-20

Candida glabrata is a yeast that can cause hazardous fungal infections with high mortality and drug resistance. The aim of this study was to determine the profile of drug susceptibility in clinical isolates of C. glabrata and review the resistance mechanisms to caspofungin. A total of 50 C. glabrata clinical isolates from Iran were tested for in vitro susceptibilities to amphotericin B, caspofungin, fluconazole and voriconazole. To investigate the mechanism of resistance to caspofungin, hotspot areas of FKS1 and FKS2 genes were sequenced and gene expression profile was evaluated. All the isolates were susceptible to amphotericin B and caspofungin. Fluconazole resistance was exhibited in four isolates. In addition, only one isolate was resistant to voriconazole. FKS2 with 12 point mutations showed more mutations compared to FKS1 that had only two mutations. All substitutions were synonymous. FKS genes were expressed at comparable levels (no statistical significance) in caspofungin-treated and non-treated cultures. The silent mutations in the hotspot areas of FKS genes and inconsiderable changes in gene expression were not associated with increased MIC (0.25μg/ml). Other mechanisms of resistance which include mutations outside the hotspot area of FKS genes could be involved in a slight increase of MIC, and they should be identified through complete FKS gene sequencing. Copyright © 2018 Asociación Española de Micología. Publicado por Elsevier España, S.L.U. All rights reserved.

Evolutionary relationships among pathogenic Candida species and relatives.

PubMed Central

Barns, S M; Lane, D J; Sogin, M L; Bibeau, C; Weisburg, W G

1991-01-01

Small subunit rRNA sequences have been determined for 10 of the most clinically important pathogenic species of the yeast genus Candida (including Torulopsis [Candida] glabrata and Yarrowia [Candida] lipolytica) and for Hansenula polymorpha. Phylogenetic analyses of these sequences and those of Saccharomyces cerevisiae, Kluyveromyces marxianus var. lactis, and Aspergillus fumigatus indicate that Candida albicans, C. tropicalis, C. parapsilosis, and C. viswanathii form a subgroup within the genus. The remaining significant pathogen, T. glabrata, falls into a second, distinct subgroup and is specifically related to S. cerevisiae and more distantly related to C. kefyr (psuedotropicalis) and K. marxianus var. lactis. The 18S rRNA sequence of Y. lipolytica has evolved rapidly in relation to the other Candida sequences examined and appears to be only distantly related to them. As anticipated, species of several other genera appear to bear specific relationships to members of the genus Candida. PMID:2007550

Silver colloidal nanoparticles: effect on matrix composition and structure of Candida albicans and Candida glabrata biofilms.

PubMed

Monteiro, D R; Silva, S; Negri, M; Gorup, L F; de Camargo, E R; Oliveira, R; Barbosa, D B; Henriques, M

2013-04-01

The aim of this study was to assess the effect of different silver nanoparticles (SN) concentrations on the matrix composition and structure of Candida albicans and Candida glabrata biofilms. Candida biofilms were developed in 6-well microtiter plates during 48 h. After, these biofilms were exposed to 13.5 or 54 μg SN ml(-1) for 24 h. Then, extracellular matrices were extracted from biofilms and analysed chemically in terms of proteins, carbohydrates and DNA. To investigate the biofilm structure, scanning electron microscopy (SEM) and epifluorescence microscopy were used. SN interfered with the matrix composition of Candida biofilms tested in terms of protein, carbohydrate and DNA, except for the protein content of C. albicans biofilm. By SEM, Candida biofilms treated with SN revealed structural differences, when compared with the control groups. Further, SN showed a trend of agglomeration within the biofilms. Epifluorescence microscopy images suggest that SN induced damage on cell walls of the Candida isolates tested. In general, irrespective of concentration, SN affected the matrix composition and structure of Candida biofilms and these findings may be related to the mechanisms of biocide action of SN. This study reveals new insights about the behaviour of SN when in contact with Candida biofilms. SN may contribute to the development of therapies to prevent or control Candida infections. © 2012 The Society for Applied Microbiology.

Promising results of cranberry in the prevention of oral Candida biofilms.

PubMed

Girardot, Marion; Guerineau, Amandine; Boudesocque, Leslie; Costa, Damien; Bazinet, Laurent; Enguehard-Gueiffier, Cécile; Imbert, Christine

2014-04-01

In the context of dental caries prevention by natural foodstuff sources, antifungal and antibiofilm activities of dry commercial extracts of cranberry fruit (Vaccinium macrocarpon Aiton) and two other red fruits (Vaccinium myrtillus L. and Malpighia punicifolia L.) were assessed on Candida albicans and Candida glabrata yeasts. When added to the culture medium, the cranberry extract displayed a significant anti-adhesion activity against Candida spp. when used at low concentrations. In addition, the pretreatment of surfaces with this extract induced an anti-adhesion activity mainly against C. glabrata yeasts and an antibiofilm activity against C. albicans. This activity was dependent on concentration, species, and strain. A phytochemical investigation bioguided by anti-adhesion tests against the two Candida species was carried out on crude cranberry juice to determine the active fractions. Three subfractions enriched in proanthocyanidins showed an anti-adhesion activity at low concentrations. This study investigated for the first time the interest of crude extracts of cranberry and cranberry juice fractions to prevent biofilms of C. glabrata. It highlighted the potency of consuming this fruit and using it as a source of anti-adhesion agents. © 2014 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

Failed Reverse Total Shoulder Arthroplasty Caused by Recurrent Candida glabrata Infection with Prior Serratia marcescens Coinfection

PubMed Central

Skedros, John G.; Keenan, Kendra E.; Updike, Wanda S.; Oliver, Marquam R.

2014-01-01

This report describes a 58-year-old insulin-dependent diabetic male patient who initially sustained a proximal humerus fracture from a fall. The fracture fixation failed and then was converted to a humeral hemiarthroplasty, which became infected with Candida glabrata and Serratia marcescens. After these infections were believed to be cured with antibacterial and antifungal treatments and two-stage irrigation and debridement, he underwent conversion to a reverse total shoulder arthroplasty. Unfortunately, the C. glabrata infection recurred and, nearly 1.5 years after implantation of the reverse total shoulder, he had a resection arthroplasty (removal of all implants and cement). His surgical and pharmacologic treatment concluded with (1) placement of a tobramycin-impregnated cement spacer also loaded with amphotericin B, with no plan for revision arthroplasty (i.e., the spacer was chronically retained), and (2) chronic use of daily oral fluconazole. We located only three reported cases of Candida species causing infection in shoulder arthroplasties (two C. albicans, one C. parapsilosis). To our knowledge, a total shoulder arthroplasty infected with C. glabrata has not been reported, nor has a case of a C. glabrata and S. marcescens periprosthetic coinfection in any joint. In addition, it is well known that S. marcescens infections are uncommon in periprosthetic joint infections. PMID:25431708

MALDI-TOF typing highlights geographical and fluconazole resistance clusters in Candida glabrata.

PubMed

Dhieb, C; Normand, A C; Al-Yasiri, M; Chaker, E; El Euch, D; Vranckx, K; Hendrickx, M; Sadfi, N; Piarroux, R; Ranque, S

2015-06-01

Utilizing matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectra for Candida glabrata typing would be a cost-effective and easy-to-use alternative to classical DNA-based typing methods. This study aimed to use MALDI-TOF for the typing of C. glabrata clinical isolates from various geographical origins and test its capacity to differentiate between fluconazole-sensitive and -resistant strains.Both microsatellite length polymorphism (MLP) and MALDI-TOF mass spectra of 58 C. glabrata isolates originating from Marseilles (France) and Tunis (Tunisia) as well as collection strains from diverse geographic origins were analyzed. The same analysis was conducted on a subset of C. glabrata isolates that were either susceptible (MIC ≤ 8 mg/l) or resistant (MIC ≥ 64 mg/l) to fluconazole.According to the seminal results, both MALDI-TOF and MLP classifications could highlight C. glabrata population structures associated with either geographical dispersal barriers (p < 10(-5)) or the selection of antifungal drug resistance traits (<10(-5)).In conclusion, MALDI-TOF geographical clustering was congruent with MPL genotyping and highlighted a significant population genetic structure according to fluconazole susceptibility in C. glabrata. Furthermore, although MALDI-TOF and MLP resulted in distinct classifications, MALDI-TOF also classified the isolates with respect to their fluconazole susceptibility profile. Further prospective studies are required to evaluate the capacity of MALDI-TOF typing to investigate C. glabrata infection outbreaks and predict the antifungal susceptibility profile of clinical laboratory isolates. © The Author 2015. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Candida/Candida biofilms. First description of dual-species Candida albicans/C. rugosa biofilm.

PubMed

Martins, Carlos Henrique Gomes; Pires, Regina Helena; Cunha, Aline Oliveira; Pereira, Cristiane Aparecida Martins; Singulani, Junya de Lacorte; Abrão, Fariza; Moraes, Thais de; Mendes-Giannini, Maria José Soares

2016-04-01

Denture liners have physical properties that favour plaque accumulation and colonization by Candida species, irritating oral tissues and causing denture stomatitis. To isolate and determine the incidence of oral Candida species in dental prostheses, oral swabs were collected from the dental prostheses of 66 patients. All the strains were screened for their ability to form biofilms; both monospecies and dual-species combinations were tested. Candida albicans (63 %) was the most frequently isolated microorganism; Candida tropicalis (14 %), Candida glabrata (13 %), Candida rugosa (5 %), Candida parapsilosis (3 %), and Candida krusei (2 %) were also detected. The XTT assay showed that C. albicans SC5314 possessed a biofilm-forming ability significantly higher (p < 0.001) than non-albicans Candida strains, after 6 h 37 °C. The total C. albicans CFU from a dual-species biofilm was less than the total CFU of a monospecies C. albicans biofilm. In contrast to the profuse hyphae verified in monospecies C. albicans biofilms, micrographies showed that the C. albicans/non-albicans Candida biofilms consisted of sparse yeast forms and profuse budding yeast cells that generated a network. These results suggested that C. albicans and the tested Candida species could co-exist in biofilms displaying apparent antagonism. The study provide the first description of C. albicans/C. rugosa mixed biofilm. Copyright © 2016 The British Mycological Society. Published by Elsevier Ltd. All rights reserved.

Influence of growth conditions on adhesion of yeast Candida spp. and Pichia spp. to stainless steel surfaces.

PubMed

Tomičić, Ružica; Raspor, Peter

2017-08-01

An understanding of adhesion behavior of Candida and Pichia yeast under different environmental conditions is key to the development of effective preventive measures against biofilm-associated infection. Hence in this study we investigated the impact of growth medium and temperature on Candida and Pichia adherence using stainless steel (AISI 304) discs with different degrees of surface roughness (Ra = 25.20-961.9 nm), material typical for the food processing industry as well as medical devices. The adhesion of the yeast strains to stainless steel surfaces grown in Malt Extract broth (MEB) or YPD broth at three temperatures (7 °C, 37 °C, 43 °C for Candida strains and 7 °C, 27 °C, 32 °C for Pichia strains) was assessed by crystal violet staining. The results showed that the nutrient content of medium significantly influenced the quantity of adhered cells by the tested yeasts. Adhesion of C. albicans and C. glabrata on stainless steel surfaces were significantly higher in MEB, whereas for C. parapsilosis and C. krusei it was YPD broth. In the case with P. pijperi and P. membranifaciens, YPD broth was more effective in promoting adhesion than MEB. On the other hand, our data indicated that temperature is a very important factor which considerably affects the adhesion of these yeast. There was also significant difference in cell adhesion on all types of stainless steel surfaces for all tested yeast. Copyright © 2017 Elsevier Ltd. All rights reserved.

Portrait of Matrix Gene Expression in Candida glabrata Biofilms with Stress Induced by Different Drugs

PubMed Central

2018-01-01

(1) Background: Candida glabrata is one of the most significant Candida species associated with severe cases of candidiasis. Biofilm formation is an important feature, closely associated with antifungal resistance, involving alterations of gene expression or mutations, which can result in the failure of antifungal treatments. Hence, the main goal of this work was to evaluate the role of a set of genes, associated with matrix production, in the resistance of C. glabrata biofilms to antifungal drugs. (2) Methods: the determination of the expression of BGL2, XOG1, FKS1, FKS2, GAS2, KNH1, UGP1, and MNN2 genes in 48-h biofilm’s cells of three C. glabrata strains was performed through quantitative real-time PCR (RT-qPCR), after contact with Fluconazole (Flu), Amphotericin B (AmB), Caspofungin (Csf), or Micafungin (Mcf). (3) Results: Mcf induced a general overexpression of the selected genes. It was verified that the genes related to the production of β-1,3-glucans (BGL2, XOG1, GAS2) had the highest expressions. (4) Conclusion: though β-1,6-glucans and mannans are an essential part of the cell and biofilm matrix, C. glabrata biofilm cells seem to contribute more to the replacement of β-1,3-glucans. Thus, these biopolymers seem to have a greater impact on the biofilm matrix composition and, consequently, a role in the biofilm resistance to antifungal drugs. PMID:29642649

CHROMagar Candida as the Sole Primary Medium for Isolation of Yeasts and as a Source Medium for the Rapid-Assimilation-of-Trehalose Test

PubMed Central

Murray, Melissa P.; Zinchuk, Riva; Larone, Davise H.

2005-01-01

The chromogenic medium BBL CHROMagar Candida (CAC) was evaluated as a sole primary medium for the isolation of yeasts from clinical specimens in which yeasts are the primary concern. Additionally, the reliability of the rapid-assimilation-of-trehalose (RAT) test in yielding correct results with isolates taken from CAC was assessed. A total of 270 throat, urine, and genital (TUG) specimens were streaked onto CAC, Sabouraud dextrose agar (SDA), inhibitory mold agar (IMA), and Mycosel (MYC). A total of 69 blood culture broths that were smear positive for yeast were streaked onto CAC and SDA. A 1-h RAT test (NCCLS M35-A) was performed simultaneously on isolates from CAC and SDA. A total of 112 TUG specimens yielded yeast colonies (CAC, 111 colonies; IMA, 105; SDA, 103; MYC, 91). The 69 blood culture yeasts grew on both CAC and SDA. Mixed cultures of yeasts were detected on 11 CAC plates but were unrecognized on other media. Colonies suspected of being C. glabrata on 32 CAC plates were all RAT test positive and confirmed to be C. glabrata; of 59 colonies with various characteristics of color and morphology on CAC, none were RAT positive, and all were conventionally identified as yeasts other than C. glabrata (sensitivity and specificity, 100%). The same isolates from SDA tested for RAT produced six false negatives and no false positives (sensitivity, 81%; specificity, 100%). The results show that CAC can be used as the sole primary medium for recovery of yeasts from clinical specimens. Additionally, isolates grown on CAC yield excellent results with the RAT test utilized in this study. PMID:15750085

CHROMagar Candida as the sole primary medium for isolation of yeasts and as a source medium for the rapid-assimilation-of-trehalose test.

PubMed

Murray, Melissa P; Zinchuk, Riva; Larone, Davise H

2005-03-01

The chromogenic medium BBL CHROMagar Candida (CAC) was evaluated as a sole primary medium for the isolation of yeasts from clinical specimens in which yeasts are the primary concern. Additionally, the reliability of the rapid-assimilation-of-trehalose (RAT) test in yielding correct results with isolates taken from CAC was assessed. A total of 270 throat, urine, and genital (TUG) specimens were streaked onto CAC, Sabouraud dextrose agar (SDA), inhibitory mold agar (IMA), and Mycosel (MYC). A total of 69 blood culture broths that were smear positive for yeast were streaked onto CAC and SDA. A 1-h RAT test (NCCLS M35-A) was performed simultaneously on isolates from CAC and SDA. A total of 112 TUG specimens yielded yeast colonies (CAC, 111 colonies; IMA, 105; SDA, 103; MYC, 91). The 69 blood culture yeasts grew on both CAC and SDA. Mixed cultures of yeasts were detected on 11 CAC plates but were unrecognized on other media. Colonies suspected of being C. glabrata on 32 CAC plates were all RAT test positive and confirmed to be C. glabrata; of 59 colonies with various characteristics of color and morphology on CAC, none were RAT positive, and all were conventionally identified as yeasts other than C. glabrata (sensitivity and specificity, 100%). The same isolates from SDA tested for RAT produced six false negatives and no false positives (sensitivity, 81%; specificity, 100%). The results show that CAC can be used as the sole primary medium for recovery of yeasts from clinical specimens. Additionally, isolates grown on CAC yield excellent results with the RAT test utilized in this study.

Antifungal Susceptibilities of Candida Species Causing Vulvovaginitis and Epidemiology of Recurrent Cases

PubMed Central

Richter, Sandra S.; Galask, Rudolph P.; Messer, Shawn A.; Hollis, Richard J.; Diekema, Daniel J.; Pfaller, Michael A.

2005-01-01

There are limited data regarding the antifungal susceptibility of yeast causing vulvovaginal candidiasis, since cultures are rarely performed. Susceptibility testing was performed on vaginal yeast isolates collected from January 1998 to March 2001 from 429 patients with suspected vulvovaginal candidiasis. The charts of 84 patients with multiple positive cultures were reviewed. The 593 yeast isolates were Candida albicans (n = 420), Candida glabrata (n = 112), Candida parapsilosis (n = 30), Candida krusei (n = 12), Saccharomyces cerevisiae ( n = 9), Candida tropicalis (n = 8), Candida lusitaniae (n = 1), and Trichosporon sp. (n = 1). Multiple species suggesting mixed infection were isolated from 27 cultures. Resistance to fluconazole and flucytosine was observed infrequently (3.7% and 3.0%); 16.2% of isolates were resistant to itraconazole (MIC ≥ 1 μg/ml). The four imidazoles (econazole, clotrimazole, miconazole, and ketoconazole) were active: 94.3 to 98.5% were susceptible at ≤1 μg/ml. Among different species, elevated fluconazole MICs (≥16 μg/ml) were only observed in C. glabrata (15.2% resistant [R], 51.8% susceptible-dose dependent [S-DD]), C. parapsilosis (3.3% S-DD), S. cerevisiae (11.1% S-DD), and C. krusei (50% S-DD, 41.7% R, considered intrinsically fluconazole resistant). Resistance to itraconazole was observed among C. glabrata (74.1%), C. krusei (58.3%), S. cerevisiae (55.6%), and C. parapsilosis (3.4%). Among 84 patients with recurrent episodes, non-albicans species were more common (42% versus 20%). A ≥4-fold rise in fluconazole MIC was observed in only one patient with C. parapsilosis. These results support the use of azoles for empirical therapy of uncomplicated candidal vulvovaginitis. Recurrent episodes are more often caused by non-albicans species, for which azole agents are less likely to be effective. PMID:15872235

Evaluation of Four Calcium Channel Blockers as Fluconazole Resistance Inhibitors in Candida glabrata.

PubMed

Alnajjar, Lina M; Bulatova, Nailya R; Darwish, Rula M

2018-04-14

In this study we aimed to evaluate the ability of four calcium channel blockers, verapamil, diltiazem, nicardipine and nifedipine to enhance sensitivity of Candida glabrata strains to fluconazole. The synergistic antifungal effect was examined by checkerboard method; fractional inhibitory concentration index (FIC) was determined. Time-kill curve method was used for the most promising combination to further evaluate the synergetic effects. nicardipine showed additive effect with fluconazole against fluconazole-resistant and fluconazole-susceptible-dose-dependent strains (DSY565 and CBS138) known to express efflux pumps but not against fluconazole-sensitive strains. Nifedipine exhibited additive effect with fluconazole in both checkerboard (0.5< FIC <1) and time-kill curve methods (<2 log10 colony-forming units (CFU)/ml decrease in viable count). Additionally, nifedipine had own antifungal effect consistently against most of the strains used in this study with minimum inhibitory concentration of 8μg/ml. nicardipine showed additive effect with fluconazole in fluconazole-resistant strains of Candida glabrata-most probably via efflux pump inhibition as demonstrated selectively in fluconazole-resistant strains with known efflux pumps. Nifedipine displayed promising antifungal effect alone and additive effects with fluconazole. Copyright © 2018. Published by Elsevier Ltd.

Systematic Phenotyping of a Large-Scale Candida glabrata Deletion Collection Reveals Novel Antifungal Tolerance Genes

PubMed Central

Hiller, Ekkehard; Istel, Fabian; Tscherner, Michael; Brunke, Sascha; Ames, Lauren; Firon, Arnaud; Green, Brian; Cabral, Vitor; Marcet-Houben, Marina; Jacobsen, Ilse D.; Quintin, Jessica; Seider, Katja; Frohner, Ingrid; Glaser, Walter; Jungwirth, Helmut; Bachellier-Bassi, Sophie; Chauvel, Murielle; Zeidler, Ute; Ferrandon, Dominique; Gabaldón, Toni; Hube, Bernhard; d'Enfert, Christophe; Rupp, Steffen; Cormack, Brendan; Haynes, Ken; Kuchler, Karl

2014-01-01

The opportunistic fungal pathogen Candida glabrata is a frequent cause of candidiasis, causing infections ranging from superficial to life-threatening disseminated disease. The inherent tolerance of C. glabrata to azole drugs makes this pathogen a serious clinical threat. To identify novel genes implicated in antifungal drug tolerance, we have constructed a large-scale C. glabrata deletion library consisting of 619 unique, individually bar-coded mutant strains, each lacking one specific gene, all together representing almost 12% of the genome. Functional analysis of this library in a series of phenotypic and fitness assays identified numerous genes required for growth of C. glabrata under normal or specific stress conditions, as well as a number of novel genes involved in tolerance to clinically important antifungal drugs such as azoles and echinocandins. We identified 38 deletion strains displaying strongly increased susceptibility to caspofungin, 28 of which encoding proteins that have not previously been linked to echinocandin tolerance. Our results demonstrate the potential of the C. glabrata mutant collection as a valuable resource in functional genomics studies of this important fungal pathogen of humans, and to facilitate the identification of putative novel antifungal drug target and virulence genes. PMID:24945925

Role of FKS Mutations in Candida glabrata: MIC Values, Echinocandin Resistance, and Multidrug Resistance

PubMed Central

Pham, Cau D.; Iqbal, Naureen; Bolden, Carol B.; Kuykendall, Randall J.; Harrison, Lee H.; Farley, Monica M.; Schaffner, William; Beldavs, Zintars G.; Chiller, Tom M.; Park, Benjamin J.; Cleveland, Angela A.

2014-01-01

Candida glabrata is the second leading cause of candidemia in U.S. hospitals. Current guidelines suggest that an echinocandin be used as the primary therapy for the treatment of C. glabrata disease due to the high rate of resistance to fluconazole. Recent case reports indicate that C. glabrata resistance to echinocandins may be increasing. We performed susceptibility testing on 1,380 isolates of C. glabrata collected between 2008 and 2013 from four U.S. cities, Atlanta, Baltimore, Knoxville, and Portland. Our analysis showed that 3.1%, 3.3%, and 3.6% of the isolates were resistant to anidulafungin, caspofungin, and micafungin, respectively. We screened 1,032 of these isolates, including all 77 that had either a resistant or intermediate MIC value with respect to at least one echinocandin, for mutations in the hot spot regions of FKS1 and FKS2, the major mechanism of echinocandin resistance. Fifty-one isolates were identified with hot spot mutations, 16 in FKS1 and 35 in FKS2. All of the isolates with an FKS mutation except one were resistant to at least one echinocandin by susceptibility testing. Of the isolates resistant to at least one echinocandin, 36% were also resistant to fluconazole. Echinocandin resistance among U.S. C. glabrata isolates is a concern, especially in light of the fact that one-third of those isolates may be multidrug resistant. Further monitoring of U.S. C. glabrata isolates for echinocandin resistance is warranted. PMID:24890592

Antifungal activity of silver nanoparticles in combination with nystatin and chlorhexidine digluconate against Candida albicans and Candida glabrata biofilms.

PubMed

Monteiro, Douglas R; Silva, Sónia; Negri, Melyssa; Gorup, Luiz F; de Camargo, Emerson R; Oliveira, Rosário; Barbosa, Debora B; Henriques, Mariana

2013-11-01

Although silver nanoparticles (SN) have been investigated as an alternative to conventional antifungal drugs in the control of Candida-associated denture stomatitis, the antifungal activity of SN in combination with antifungal drugs against Candida biofilms remains unknown. Therefore, the aim of this study was to evaluate the antifungal efficacy of SN in combination with nystatin (NYT) or chlorhexidine digluconate (CHG) against Candida albicans and Candida glabrata biofilms. The drugs alone or combined with SN were applied on mature Candida biofilms (48 h), and after 24 h of treatment their antibiofilm activities were assessed by total biomass quantification (by crystal violet staining) and colony forming units enumeration. The structure of Candida biofilms was analysed by scanning electron microscopy (SEM) images. The data indicated that SN combined with either NYT or CHG demonstrated synergistic antibiofilm activity, and this activity was dependent on the species and on the drug concentrations used. SEM images showed that some drug combinations were able to disrupt Candida biofilms. The results of this study suggest that the combination of SN with NYT or CHG may have clinical implications in the treatment of denture stomatitis. However, further studies are needed before recommending the use of these drugs safely in clinical situations. © 2013 Blackwell Verlag GmbH.

Dissection of Ire1 Functions Reveals Stress Response Mechanisms Uniquely Evolved in Candida glabrata

PubMed Central

Miyazaki, Taiga; Nakayama, Hironobu; Nagayoshi, Yohsuke; Kakeya, Hiroshi; Kohno, Shigeru

2013-01-01

Proper protein folding in the endoplasmic reticulum (ER) is vital in all eukaryotes. When misfolded proteins accumulate in the ER lumen, the transmembrane kinase/endoribonuclease Ire1 initiates splicing of HAC1 mRNA to generate the bZIP transcription factor Hac1, which subsequently activates its target genes to increase the protein-folding capacity of the ER. This cellular machinery, called the unfolded protein response (UPR), is believed to be an evolutionarily conserved mechanism in eukaryotes. In this study, we comprehensively characterized mutant phenotypes of IRE1 and other related genes in the human fungal pathogen Candida glabrata. Unexpectedly, Ire1 was required for the ER stress response independently of Hac1 in this fungus. C. glabrata Ire1 did not cleave mRNAs encoding Hac1 and other bZIP transcription factors identified in the C. glabrata genome. Microarray analysis revealed that the transcriptional response to ER stress is not mediated by Ire1, but instead is dependent largely on calcineurin signaling and partially on the Slt2 MAPK pathway. The loss of Ire1 alone did not confer increased antifungal susceptibility in C. glabrata contrary to UPR-defective mutants in other fungi. Taken together, our results suggest that the canonical Ire1-Hac1 UPR is not conserved in C. glabrata. It is known in metazoans that active Ire1 nonspecifically cleaves and degrades a subset of ER-localized mRNAs to reduce the ER load. Intriguingly, this cellular response could occur in an Ire1 nuclease-dependent fashion in C. glabrata. We also uncovered the attenuated virulence of the C. glabrata Δire1 mutant in a mouse model of disseminated candidiasis. This study has unveiled the unique evolution of ER stress response mechanisms in C. glabrata. PMID:23382685

Yeast Colonization and Drug Susceptibility Pattern in the Pediatric Patients With Neutropenia

PubMed Central

Haddadi, Pedram; Zareifar, Soheila; Badiee, Parisa; Alborzi, Abdolvahab; Mokhtari, Maral; Zomorodian, Kamiar; Pakshir, Keyvan; Jafarian, Hadis

2014-01-01

Background: Pediatric patients with neutropenia are vulnerable to invasive Candida infections. Candida is the primary cause of fungal infections, particularly in immunosuppressed patients. Candida albicans has been the most common etiologic agent of these infections, affecting 48% of patients Objectives: The aim of this study was to identify Candida spp. isolated from children with neutropenia and determine the antifungal susceptibility pattern of the isolated yeasts. Patients and Methods: In this study 188 children with neutropenia were recruited, fungal surveillance cultures were carried out on nose, oropharynx, stool, and urine samples. Identification of Candida strains was performed using germ tube and chlamydospore production tests on an API 20 C AUX system. Susceptibility testing on seven antifungal agents was performed using the agar-based E-test method. Results: A total of 229 yeasts were isolated. Among those, C. albicans was the most common species followed by C. krusei, C. parapsilosis, C. glabrata, C. tropicalis, C. famata, C. dubliniensis, C. kefyr, and other Candida species. C. glabrata was the most resistant isolated yeasts, which was 70% resistant to fluconazole and 50% to itraconazole, 7.5% to amphotericin B and 14% to ketoconazole. All the tested species were mostly sensitive to caspofungin. Conclusions: Knowledge about the susceptibility patterns of colonized Candida spp. can be helpful for clinicians to manage pediatric patients with neutropenia. In this study, caspofungin was the most effective antifungal agent against the colonized Candida spp. followed by conventional amphotericin B. PMID:25485060

The Phosphoinositide 3-Kinase Regulates Retrograde Trafficking of the Iron Permease CgFtr1 and Iron Homeostasis in Candida glabrata*

PubMed Central

Sharma, Vandana; Purushotham, Rajaram; Kaur, Rupinder

2016-01-01

The phosphoinositide 3-kinase (PI3K), which phosphorylates phosphatidylinositol and produces PI3P, has been implicated in protein trafficking, intracellular survival, and virulence in the pathogenic yeast Candida glabrata. Here, we demonstrate PI3-kinase (CgVps34) to be essential for maintenance of cellular iron homeostasis. We examine how CgVps34 regulates the fundamental process of iron acquisition, and underscore its function in vesicular trafficking as a central determinant. RNA sequencing analysis revealed iron homeostasis genes to be differentially expressed upon CgVps34 disruption. Consistently, the Cgvps34Δ mutant displayed growth attenuation in low- and high-iron media, increased intracellular iron content, elevated mitochondrial aconitase activity, impaired biofilm formation, and extenuated mouse organ colonization potential. Furthermore, we demonstrate for the first time that C. glabrata cells respond to iron limitation by expressing the iron permease CgFtr1 primarily on the cell membrane, and to iron excess via internalization of the plasma membrane-localized CgFtr1 to the vacuole. Our data show that CgVps34 is essential for the latter process. We also report that macrophage-internalized C. glabrata cells express CgFtr1 on the cell membrane indicative of an iron-restricted macrophage internal milieu, and Cgvps34Δ cells display better survival in iron-enriched medium-cultured macrophages. Overall, our data reveal the centrality of PI3K signaling in iron metabolism and host colonization. PMID:27729452

Comparison of Pathogenesis and Host Immune Responses to Candida glabrata and Candida albicans in Systemically Infected Immunocompetent Mice

PubMed Central

Brieland, Joan; Essig, David; Jackson, Craig; Frank, Doyle; Loebenberg, David; Menzel, Fred; Arnold, Brian; DiDomenico, Beth; Hare, Roberta

2001-01-01

Cytokine-mediated host defense against Candida glabrata infection was compared to that against C. albicans, using immunocompetent murine models of systemic candidiasis. The pathogenesis of infection was evaluated morphologically and by culture of target organs, while the kinetics of induction of cytokine mRNAs and corresponding proteins were determined in kidneys by real-time reverse transcription-PCR and cytokine-specific murine enzyme-linked immunosorbent assays, respectively. Systemic infection with C. glabrata resulted in a chronic, nonfatal infection with recovery of organisms from kidneys, while intravenous inoculation with C. albicans resulted in rapid mortality with logarithmic growth of organisms in kidneys and recovery of C. albicans from the spleen, liver, and lungs. Survival of C. glabrata-infected mice was associated with rapid induction of mRNAs and corresponding immunoreactive proteins for the proinflammatory cytokines tumor necrosis factor alpha (TNF-α), interleukin-12 (IL-12), and gamma interferon (IFN-γ) and the lack of induction of protein for the anti-inflammatory cytokine IL-10. In contrast, mortality in C. albicans-infected mice was associated with induction of mRNA and corresponding protein for IL-10 but delayed (i.e., TNF-α) or absent (i.e., IL-12 and IFN-γ) induction of immunoreactive proinflammatory cytokines. Mice were subsequently treated with cytokine-specific neutralizing monoclonal antibodies (MAbs) to TNF-α, IL-12, or IFN-γ, and the effect on growth of C. glabrata in kidneys was assessed. Neutralization of endogenous TNF-α resulted in a significant increase in C. glabrata organisms compared to similarly infected mice administered an isotype-matched control MAb, while neutralization of endogenous IL-12 or IFN-γ had no significant effect on C. glabrata replication. These results demonstrate that in response to intravenous inoculation of C. glabrata, immunocompetent mice develop chronic nonfatal renal infections which are

A Host-Pathogen Interaction Screen Identifies ada2 as a Mediator of Candida glabrata Defenses Against Reactive Oxygen Species.

PubMed

Kounatidis, Ilias; Ames, Lauren; Mistry, Rupal; Ho, Hsueh-Lui; Haynes, Ken; Ligoxygakis, Petros

2018-05-04

Candida glabrata ( C. glabrata ) forms part of the normal human gut microbiota but can cause life-threatening invasive infections in immune-compromised individuals. C. glabrata displays high resistance to common azole antifungals, which necessitates new treatments. In this investigation, we identified five C. glabrata deletion mutants ( ∆ada2 , ∆bas1 , ∆ hir3, ∆ino2 and ∆met31 ) from a library of 196 transcription factor mutants that were unable to grow and activate an immune response in Drosophila larvae. This highlighted the importance of these transcription factors in C. glabrata infectivity. Further ex vivo investigation into these mutants revealed the requirement of C. glabrata ADA2 for oxidative stress tolerance. We confirmed this observation in vivo whereby growth of the C. glabrata Δada2 strain was permitted only in flies with suppressed production of reactive oxygen species (ROS). Conversely, overexpression of ADA2 promoted C. glabrata replication in infected wild type larvae resulting in larval killing. We propose that ADA2 orchestrates the response of C. glabrata against ROS-mediated immune defenses during infection. With the need to find alternative antifungal treatment for C. glabrata infections, genes required for survival in the host environment, such as ADA2 , provide promising potential targets. Copyright © 2018 Kounatidis et al.

The Effectiveness of Voriconazole in Therapy of Candida glabrata's Biofilms Oral Infections and Its Influence on the Matrix Composition and Gene Expression.

PubMed

Rodrigues, Célia F; Gonçalves, Bruna; Rodrigues, Maria Elisa; Silva, Sónia; Azeredo, Joana; Henriques, Mariana

2017-08-01

Candida glabrata is one of most prevalent yeast in fungal infections, especially in immunocompromised patients. Its azole resistance results in a low therapeutic response, particularly when associated with biofilms. The main goal of this work was to study the effectiveness of voriconazole (Vcz) against C. glabrata biofilms oral pathologies, as esophageal or oropharyngeal candidiasis. Antifungal susceptibilities were determined in pre-formed 24-h-biofilms and ERG genes expression was determined by qRT-PCR. Protein quantification was performed using BCA ® Kit, carbohydrate was estimated according to the Dubois assay and β-1,3 glucans concentration were determined using Glucatell ® kit. Finally, ergosterol, Vcz, and fluconazole (Flu) concentrations within the biofilm matrices were determined by RP-HPLC. Results showed that C. glabrata biofilms were more susceptible to Vcz than to Flu and that ERG genes expression evidenced an overexpression of the three ERG genes in the presence of both azoles. The matrix content presented a remarked decrease in proteins and an increase in carbohydrates, namely β-1,3 glucans. Ergosterol was successfully detected and quantified in the biofilm matrices, with no differences in all the considered conditions. Vcz demonstrated better diffusion through the biofilms and better cell penetration capacities, than Flu, indicating that the structure of the drug molecule fully influences its dissemination through the biofilm matrices. This work showed that Vcz is notably more effective than Flu for the treatment of resistant C. glabrata oral biofilms, which demonstrates a clinical relevance in its future use for the treatment of oropharyngeal/esophageal candidiasis caused by this species.

Role of FKS Mutations in Candida glabrata: MIC values, echinocandin resistance, and multidrug resistance.

PubMed

Pham, Cau D; Iqbal, Naureen; Bolden, Carol B; Kuykendall, Randall J; Harrison, Lee H; Farley, Monica M; Schaffner, William; Beldavs, Zintars G; Chiller, Tom M; Park, Benjamin J; Cleveland, Angela A; Lockhart, Shawn R

2014-08-01

Candida glabrata is the second leading cause of candidemia in U.S. hospitals. Current guidelines suggest that an echinocandin be used as the primary therapy for the treatment of C. glabrata disease due to the high rate of resistance to fluconazole. Recent case reports indicate that C. glabrata resistance to echinocandins may be increasing. We performed susceptibility testing on 1,380 isolates of C. glabrata collected between 2008 and 2013 from four U.S. cities, Atlanta, Baltimore, Knoxville, and Portland. Our analysis showed that 3.1%, 3.3%, and 3.6% of the isolates were resistant to anidulafungin, caspofungin, and micafungin, respectively. We screened 1,032 of these isolates, including all 77 that had either a resistant or intermediate MIC value with respect to at least one echinocandin, for mutations in the hot spot regions of FKS1 and FKS2, the major mechanism of echinocandin resistance. Fifty-one isolates were identified with hot spot mutations, 16 in FKS1 and 35 in FKS2. All of the isolates with an FKS mutation except one were resistant to at least one echinocandin by susceptibility testing. Of the isolates resistant to at least one echinocandin, 36% were also resistant to fluconazole. Echinocandin resistance among U.S. C. glabrata isolates is a concern, especially in light of the fact that one-third of those isolates may be multidrug resistant. Further monitoring of U.S. C. glabrata isolates for echinocandin resistance is warranted. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

A rare case of fungal endocarditis caused by Candida glabrata after completion of antibiotic therapy for Streptococcus endocarditis.

PubMed

Tsugu, Toshimitsu; Murata, Mitsushige; Iwanaga, Shiro; Kitamura, Yohei; Inoue, Soushin; Fukuda, Keiichi

2015-04-01

We present the rare case of a 76-year-old female with infective endocarditis (IE) caused by Candida glabrata. Immediately before developing the present infection, she developed IE with vegetation on the mitral annular calcification, which was caused by Streptococcus mitis and successfully treated with penicillin-G and gentamicin. However, her fever recurred, and she developed disseminated intravascular coagulation. Blood culture revealed C. glabrata, and echocardiography revealed new vegetation on the mitral valve. After 4 weeks of treatment with micafungin, prosthetic valve replacement was performed, followed by additional administration of micafungin for 4 weeks (total of 8 weeks). No relapse at 9 months after surgery has been observed. C. glabrata endocarditis is extremely rare and difficult to manage. Our case and review of past reported cases suggest that early diagnosis and initiation of treatment contribute to good prognosis of C. glabrata endocarditis.

Mutants in the Candida glabrata Glycerol Channels Are Sensitized to Cell Wall Stress

PubMed Central

Beese-Sims, Sara E.; Pan, Shih-Jung; Lee, Jongmin; Hwang-Wong, Elizabeth; Cormack, Brendan P.

2012-01-01

Many fungal species use glycerol as a compatible solute with which to maintain osmotic homeostasis in response to changes in external osmolarity. In Saccharomyces cerevisiae, intracellular glycerol concentrations are regulated largely by the high osmolarity glycerol (HOG) response pathway, both through induction of glycerol biosynthesis and control of its flux through the plasma membrane Fps1 glycerol channel. The channel activity of Fps1 is also controlled by a pair of positive regulators, Rgc1 and Rgc2. In this study, we demonstrate that Candida glabrata, a fungal pathogen that possesses two Fps1 orthologs and two Rgc1/-2 orthologs, accumulates glycerol in response to hyperosmotic stress. We present an initial characterization of mutants with deletions in the C. glabrata FPS1 (CAGL0C03267 [www.candidagenome.org]) and FPS2 (CAGL0E03894) genes and find that a double mutant accumulates glycerol, experiences constitutive cell wall stress, and is hypersensitive to treatment by caspofungin, an antifungal agent that targets the cell wall. This mutant is cleared more efficiently in mouse infections than is wild-type C. glabrata by caspofungin treatment. Finally, we demonstrate that one of the C. glabrata RGC orthologs complements an S. cerevisiae rgc1 rgc2 null mutant, supporting the conclusion that this regulatory assembly is conserved between these species. PMID:23087370

Enhanced oxidative killing of azole-resistant Candida glabrata strains with ERG11 deletion.

PubMed Central

Kan, V L; Geber, A; Bennett, J E

1996-01-01

The susceptibility of genetically defined Candida glabrata strains to killing by H2O2 and neutrophils was assessed. Fluconazole-susceptible L5L and L5D strains demonstrated survival rates higher than those of two fluconazole-resistant strains lacking the ERG11 gene coding for 14 alpha-demethylase. Fluconazole resistance can occur by mechanisms which increase fungal susceptibility to oxidative killing by H2O2 and neutrophils. PMID:8807069

Convergent Evolution of Calcineurin Pathway Roles in Thermotolerance and Virulence in Candida glabrata

PubMed Central

Chen, Ying-Lien; Konieczka, Jay H.; Springer, Deborah J.; Bowen, Samantha E.; Zhang, Jing; Silao, Fitz Gerald S.; Bungay, Alice Alma C.; Bigol, Ursela G.; Nicolas, Marilou G.; Abraham, Soman N.; Thompson, Dawn A.; Regev, Aviv; Heitman, Joseph

2012-01-01

Candida glabrata is an emerging human fungal pathogen that is frequently drug tolerant, resulting in difficulties in treatment and a higher mortality in immunocompromised patients. The calcium-activated protein phosphatase calcineurin plays critical roles in controlling drug tolerance, hyphal growth, and virulence in diverse fungal pathogens via distinct mechanisms involving survival in serum or growth at host temperature (37° and higher). Here, we comprehensively studied the calcineurin signaling cascade in C. glabrata and found novel and uncharacterized functions of calcineurin and its downstream target Crz1 in governing thermotolerance, intracellular architecture, and pathogenesis in murine ocular, urinary tract, and systemic infections. This represents a second independent origin of a role for calcineurin in thermotolerant growth of a major human fungal pathogen, distinct from that which arose independently in Cryptococcus neoformans. Calcineurin also promotes survival of C. glabrata in serum via mechanisms distinct from C. albicans and thereby enables establishment of tissue colonization in a murine systemic infection model. To understand calcineurin signaling in detail, we performed global transcript profiling analysis and identified calcineurin- and Crz1-dependent genes in C. glabrata involved in cell wall biosynthesis, heat shock responses, and calcineurin function. Regulators of calcineurin (RCN) are a novel family of calcineurin modifiers, and two members of this family were identified in C. glabrata: Rcn1 and Rcn2. Our studies demonstrate that Rcn2 expression is controlled by calcineurin and Crz1 to function as a feedback inhibitor of calcineurin in a circuit required for calcium tolerance in C. glabrata. In contrast, the calcineurin regulator Rcn1 activates calcineurin signaling. Interestingly, neither Rcn1 nor Rcn2 is required for virulence in a murine systemic infection model. Taken together, our findings show that calcineurin signaling plays

Lab-scale preparations of Candida albicans and dual Candida albicans-Candida glabrata biofilms on the surface of medical-grade polyvinyl chloride (PVC) perfusion tube using a modified gravity-supported free-flow biofilm incubator (GS-FFBI).

PubMed

Shao, Jing; Lu, KeQiao; Tian, Ge; Cui, YanYan; Yan, YuanYuan; Wang, TianMing; Zhang, XinLong; Wang, ChangZhong

2015-02-01

The assembly of a man-made gravity-supported free-flow biofilm incubator (GS-FFBI) was described, which was composed of a gas cushion injector and four incubators. The GS-FFBI had the characteristics of (i) a bottom-up flow direction, and (ii) lab-scale biofilm preparation without the use of a multichannel pump. Two opportunistic fungal strains, namely Candida albicans and Candida glabrata, were employed to incubate C. albicans and dual C. albicans-C. glabrata biofilms on the surface of medical-grade polyvinyl chloride perfusion tube. In terms of the results from {2, 3-bis (2-methoxy-4-nitro-5-sulfo-phenyl)-2H-tetrazolium-5-carboxanilide} (XTT) assay, dry weight measurement, colony-forming unit counting, susceptibility test, and scanning electron microscopy, it was demonstrated that GS-FFBI could form both stable single and dual Candida biofilms with no significant variations among the four incubators or the three daily incubations within 21h, and could operate for at least 96h smoothly with no contamination of stock medium. The results also indicated, for the first time, that C. albicans and C. glabrata might be co-existent competitively and symbiotically in the dual biofilms with flowing media. GS-FFBI would be a useful device to study in vitro morphological and physiological features of microbial biofilms in the medical settings. Copyright © 2014 Elsevier B.V. All rights reserved.

Synergistic effects of tacrolimus and azole antifungal compounds in fluconazole-susceptible and fluconazole-resistant Candida glabrata isolates.

PubMed

Denardi, Laura Bedin; Mario, Débora Alves Nunes; Loreto, Érico Silva; Santurio, Janio Morais; Alves, Sydney Hartz

2015-03-01

In vitro interaction between tacrolimus (FK506) and four azoles (fluconazole, ketoconazole, itraconazole and voriconazole) against thirty clinical isolates of both fluconazole susceptible and -resistant Candida glabrata were evaluated by the checkerboard microdilution method. Synergistic, indifferent or antagonism interactions were found for combinations of the antifungal agents and FK506. A larger synergistic effect was observed for the combinations of FK506 with itraconazole and voriconazole (43%), followed by that of the combination with ketoconazole (37%), against fluconazole-susceptible isolates. For fluconazole-resistant C. glabrata , a higher synergistic effect was obtained from FK506 combined with ketoconazole (77%), itraconazole (73%), voriconazole (63%) and fluconazole (60%). The synergisms that we observed in vitro , notably against fluconazole-resistant C. glabrata isolates, are promising and warrant further analysis of their applications in experimental in vivo studies.

Seasonal variation of the upper digestive tract yeast flora of feral pigeons

USGS Publications Warehouse

Kocan, R.M.; Hasenclever, H.F.

1974-01-01

Feral pigeons were sampled over a 16-month period to determine whether their normal yeast flora varied according to season. Candida albicans and Saccharomyces telluris occurred during the entire sampling period, with C. albicans reaching its highest levels between August and January and S. telluris peaking from March through May. Candida krusei was present for 10 months but exhibited no predictable variation in density. Candida tropicalis, C. guilliermondii and Geotrichum were isolated on several occasions while C. lusitaniae, C. pseudotropicalis and Torulopsis glabrata were each isolated once. The high levels of infection and frequency of occurrence of some yeast species make the feral pigeon highly suspect as a carrier and disseminator of potentially pathogenic yeast.

A Murine Model of Candida glabrata Vaginitis Shows No Evidence of an Inflammatory Immunopathogenic Response.

PubMed

Nash, Evelyn E; Peters, Brian M; Lilly, Elizabeth A; Noverr, Mairi C; Fidel, Paul L

2016-01-01

Candida glabrata is the second most common organism isolated from women with vulvovaginal candidiasis (VVC), particularly in women with uncontrolled diabetes mellitus. However, mechanisms involved in the pathogenesis of C. glabrata-associated VVC are unknown and have not been studied at any depth in animal models. The objective of this study was to evaluate host responses to infection following efforts to optimize a murine model of C. glabrata VVC. For this, various designs were evaluated for consistent experimental vaginal colonization (i.e., type 1 and type 2 diabetic mice, exogenous estrogen, varying inocula, and co-infection with C. albicans). Upon model optimization, vaginal fungal burden and polymorphonuclear neutrophil (PMN) recruitment were assessed longitudinally over 21 days post-inoculation, together with vaginal concentrations of IL-1β, S100A8 alarmin, lactate dehydrogenase (LDH), and in vivo biofilm formation. Consistent and sustained vaginal colonization with C. glabrata was achieved in estrogenized streptozotocin-induced type 1 diabetic mice. Vaginal PMN infiltration was consistently low, with IL-1β, S100A8, and LDH concentrations similar to uninoculated mice. Biofilm formation was not detected in vivo, and co-infection with C. albicans did not induce synergistic immunopathogenic effects. This data suggests that experimental vaginal colonization of C. glabrata is not associated with an inflammatory immunopathogenic response or biofilm formation.

A Murine Model of Candida glabrata Vaginitis Shows No Evidence of an Inflammatory Immunopathogenic Response

PubMed Central

Nash, Evelyn E.; Peters, Brian M.; Lilly, Elizabeth A.; Noverr, Mairi C.; Fidel, Paul L.

2016-01-01

Candida glabrata is the second most common organism isolated from women with vulvovaginal candidiasis (VVC), particularly in women with uncontrolled diabetes mellitus. However, mechanisms involved in the pathogenesis of C. glabrata-associated VVC are unknown and have not been studied at any depth in animal models. The objective of this study was to evaluate host responses to infection following efforts to optimize a murine model of C. glabrata VVC. For this, various designs were evaluated for consistent experimental vaginal colonization (i.e., type 1 and type 2 diabetic mice, exogenous estrogen, varying inocula, and co-infection with C. albicans). Upon model optimization, vaginal fungal burden and polymorphonuclear neutrophil (PMN) recruitment were assessed longitudinally over 21 days post-inoculation, together with vaginal concentrations of IL-1β, S100A8 alarmin, lactate dehydrogenase (LDH), and in vivo biofilm formation. Consistent and sustained vaginal colonization with C. glabrata was achieved in estrogenized streptozotocin-induced type 1 diabetic mice. Vaginal PMN infiltration was consistently low, with IL-1β, S100A8, and LDH concentrations similar to uninoculated mice. Biofilm formation was not detected in vivo, and co-infection with C. albicans did not induce synergistic immunopathogenic effects. This data suggests that experimental vaginal colonization of C. glabrata is not associated with an inflammatory immunopathogenic response or biofilm formation. PMID:26807975

Yeasts associated with the curculionid beetle Xyloterinus politus: Candida xyloterini sp. nov., Candida palmyrensis sp. nov. and three common ambrosia yeasts.

PubMed

Suh, Sung-Oui; Zhou, Jianlong

2010-07-01

Seven yeast strains were isolated from the body surface and galleries of Xyloterinus politus, the ambrosia beetle that attacks black oak trees. Based on rDNA sequence comparisons and other taxonomic characteristics, five of the strains were identified as members of the species Saccharomycopsis microspora, Wickerhamomyces hampshirensis and Candida mycetangii, which have been reported previously as being associated with insects. The remaining two yeast strains were proposed as representatives of two novel species, Candida xyloterini sp. nov. (type strain ATCC 62898(T)=CBS 11547(T)) and Candida palmyrensis sp. nov. (type strain ATCC 62899(T)=CBS 11546(T)). C. xyloterini sp. nov. is a close sister taxon to Ogataea dorogensis and assimilates methanol as a sole carbon source but lacks ascospores. On the other hand, C. palmyrensis sp. nov. is phylogenetically distinct from any other ambrosia yeast reported so far. The species was placed near Candida sophiae-reginae and Candida beechii based on DNA sequence analyses, but neither of these were close sister taxa to C. palmyrensis sp. nov.

The Candida Pathogenic Species Complex

PubMed Central

Turner, Siobhán A.; Butler, Geraldine

2014-01-01

Candida species are the most common causes of fungal infection. Approximately 90% of infections are caused by five species: Candida albicans, Candida glabrata, Candida tropicalis, Candida parapsilosis, and Candida krusei. Three (C. albicans, C. tropicalis, and C. parapsilosis) belong to the CTG clade, in which the CTG codon is translated as serine and not leucine. C. albicans remains the most commonly isolated but is decreasing relative to the other species. The increasing incidence of C. glabrata is related to its reduced susceptibility to azole drugs. Genome analysis suggests that virulence in the CTG clade is associated with expansion of gene families, particularly of cell wall genes. Similar independent processes took place in the C. glabrata species group. Gene loss and expansion in an ancestor of C. glabrata may have resulted in preadaptations that enabled pathogenicity. PMID:25183855

[Yeast colonization of urinary catheters and the significance of biofilm formation].

PubMed

Růžička, Filip; Holá, Veronika; Mahelová, Martina; Procházková, Alena

2012-08-01

Urinary catheters are colonized by a wide range of microorganisms, including numerous yeasts. The catheters are usually colonized by more microbial species forming a community - multispecies biofilm. Catheter colonization usually does not affect the patient's clinical status in any significant way. On the other hand, the biofilm can become a source of endogenous infection and its presence can affect functionality of the catheter and formation of urinary stones. Material a A total of 721 urinary catheters were studied. Microorganisms were released from catheters by sonication and subsequently cultured. Their identification was performed with the use of common phenotypic tests, as well as using MALDI TOF. Yeasts whose identification was ambiguous were recognized by sequencing. Biofilm formation was assessed by growth in a microtiter plate. Yeast colonization was proved in 244 urinary catheters. However, a total of 274 yeast strains were isolated. Most of them occurred together with other yeast species and/or bacteria on the catheters, producing multispecies biofilm there. The most frequent species was Candida albicans (a total of 144 isolated strains), followed by Candida glabrata (41), Candida tropicalis (41) and Candida parapsilosis sensu stricto (14). Other isolated species were as follows: Candida kefyr (10), Candida krusei (9), Candida fabianii (6), Candida lusitaniae (5), Candida dubliniensis (3) and Saccharomyces cerevisiae (one case). Most of the yeasts rather readily formed a firmly adhering biofilm layer on artificial surfaces.

Candida krusei form mycelia along agar surfaces towards each other and other Candida species.

PubMed

Fleischmann, Jacob; Broeckling, Corey D; Lyons, Sarah

2017-03-11

Candida krusei has been known to exhibit communal interactions such as pellicle formation and crawling out of nutritional broth. We noticed another possible interaction on agar surfaces, where C. krusei yeast cells formed mycelia along agar surfaces toward each other. We report here the results of experiments to study this interaction. When C.krusei yeast cells are plated in parallel streaks, they form mycelia along agar surfaces toward other yeasts. They also detect the presence of Candida albicans and Candida glabrata across agar surfaces, while the latter two react neither to their own kind, nor to C. krusei. Secreted molecule(s) are likely involved as C.krusei does not react to heat killed C. krusei. Timing and rate of mycelia formation across distances suggests that mycelia start forming when a secreted molecule(s) on agar surface reaches a certain concentration. We detected farnesol, tyrosol and tryptophol molecules that may be involved with mycelial formation, on the agar surfaces between yeast streaks. Unexpectedly the amounts detected between streaks were significantly higher than would have expected from additive amounts of two streaks. All three Candida species secreted these molecules. When tested on agar surface however, none of these molecules individually or combined induced mycelia formation by C. krusei. Our data confirms another communal interaction by C. krusei, manifested by formation of mycelia by yeast cells toward their own kind and other yeasts on agar surfaces. We detected secretion of farnesol, tyrosol and tryptophol by C. krusei but none of these molecules induced this activity on agar surface making it unlikely that they are the ones utilized by this yeast for this activity.

Repeat-Associated Fission Yeast-Like Regional Centromeres in the Ascomycetous Budding Yeast Candida tropicalis

PubMed Central

Chatterjee, Gautam; Sankaranarayanan, Sundar Ram; Guin, Krishnendu; Thattikota, Yogitha; Padmanabhan, Sreedevi; Siddharthan, Rahul; Sanyal, Kaustuv

2016-01-01

The centromere, on which kinetochore proteins assemble, ensures precise chromosome segregation. Centromeres are largely specified by the histone H3 variant CENP-A (also known as Cse4 in yeasts). Structurally, centromere DNA sequences are highly diverse in nature. However, the evolutionary consequence of these structural diversities on de novo CENP-A chromatin formation remains elusive. Here, we report the identification of centromeres, as the binding sites of four evolutionarily conserved kinetochore proteins, in the human pathogenic budding yeast Candida tropicalis. Each of the seven centromeres comprises a 2 to 5 kb non-repetitive mid core flanked by 2 to 5 kb inverted repeats. The repeat-associated centromeres of C. tropicalis all share a high degree of sequence conservation with each other and are strikingly diverged from the unique and mostly non-repetitive centromeres of related Candida species—Candida albicans, Candida dubliniensis, and Candida lusitaniae. Using a plasmid-based assay, we further demonstrate that pericentric inverted repeats and the underlying DNA sequence provide a structural determinant in CENP-A recruitment in C. tropicalis, as opposed to epigenetically regulated CENP-A loading at centromeres in C. albicans. Thus, the centromere structure and its influence on de novo CENP-A recruitment has been significantly rewired in closely related Candida species. Strikingly, the centromere structural properties along with role of pericentric repeats in de novo CENP-A loading in C. tropicalis are more reminiscent to those of the distantly related fission yeast Schizosaccharomyces pombe. Taken together, we demonstrate, for the first time, fission yeast-like repeat-associated centromeres in an ascomycetous budding yeast. PMID:26845548

Development of a Candida glabrata dominant nutritional transformation marker utilizing the Aspergillus nidulans acetamidase gene (amdS).

PubMed

Fu, Jianmin; Blaylock, Morganne; Wickes, Cameron F; Welte, William; Mehrtash, Adrian; Wiederhold, Nathan; Wickes, Brian L

2016-05-01

The gene encoding Aspergillus nidulans acetamidase (amdS) was placed under control of Candida albicans ACT1 promoter and terminator sequences and then cloned into a plasmid containing C. glabrata ARS10,CEN8 or ARS10+CEN8 sequences. All plasmids transformed C. glabrata wild-type cells to acetamide+, with the ARS-only containing plasmid transforming cells at the highest frequencies (>1.0 × 10(4) transformants μg(-1)). Plasmids were rapidly lost under non-selective conditions with the frequency dependent on chromosomal element, thus recycling the acetamide- phenotype. The amdS plasmid was used to transform a set of clinical isolates resistant to a variety of antifungal drugs. All strains were successfully transformed to the acetamide+ phenotype at high frequency, confirming that this plasmid construct could be used as a simple dominant marker on virtually any strain. Gap repair experiments demonstrated that just as in Saccharomyces cerevisiae, gap repair functions efficiently inC. glabrata, suggesting that C. glabrata has numerous similarities toS. cerevisiae with regard to ease of molecular manipulation. The amdS system is inexpensive and efficient, and combined with existing C. glabrata plasmid elements, confers a high transformation frequency for C. glabrata with a phenotype that can be easily recycled. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Risk assessment for the spread of Candida sp. in dental chair unit waterlines using molecular techniques.

PubMed

Mazari, Wissame; Boucherit-Otmani, Zahia; El Haci, Imad Abdelhamid; Ilahi, Amine; Boucherit, Kebir

2018-05-04

The aim of this study was to evaluate the presence of yeasts in dental chair unit waterlines (DCUWLs) and to test their ability to form biofilms. Eighteen dental waterlines were analysed by culture in liquid Sabouraud in order to allow the quantification and the purification of isolated yeasts from their internal surfaces. All isolates were identified by standard laboratory procedures, including CHROMagar Candida medium for orientation, commercial yeast identification system Api Candida, MALDI-TOF MS and DNA sequencing. To evaluate their kinetics of antifungal susceptibility during different phases of biofilm formation, these yeasts were subjected to three antifungal agents. From the 18 DCUWLs studied, 10 were altered (55.56%). Eleven strains of Candida sp. [Candida albicans (2), Candida guilliermondii (5) and Candida glabrata (4)] and two species of non-Candida; Rhodotorula spp. (1) and Trichosporon spp. (2) were identified. The majority of yeasts in planktonic form were susceptible to amphotericin B, caspofungin and voriconazole, except C. albicans was resistant to voriconazole. In the biofilm form, caspofungin was the most effective antifungal agent for all isolated strains. For the other antifungal agents, sessile cells were resistant. Several types of yeasts were identified; the most frequently isolated genus was Candida. The majority of these yeasts had the ability to form biofilms and resisted antifungal agents used in this study. © 2018 FDI World Dental Federation.

Epithelial GM-CSF induction by Candida glabrata.

PubMed

Li, L; Dongari-Bagtzoglou, A

2009-08-01

The main cytokine induced by the interaction of oral epithelial cells with C. glabrata is granulocyte monocyte colony-stimulating factor (GM-CSF); however, the mechanisms regulating this response are unknown. Based on previously published information on the interactions of C. albicans with oral epithelial cells, we hypothesized that interaction with viable C. glabrata triggers GM-CSF synthesis via NF-kappaB activation. We found that C. glabrata-induced GM-CSF synthesis was adhesion-dependent, enhanced by endocytosis, and required fungal viability. NF-kappaB activation was noted during interaction of epithelial cells with C. glabrata, and pre-treatment with an NF-kappaB inhibitor partly inhibited GM-CSF synthesis. Blocking TLR4 with anti-TLR4 antibody did not inhibit GM-CSF production. In contrast, an anti-CDw17 antibody triggered significant inhibition of NF-kappaB activation and GM-CSF synthesis. beta-glucans did not stimulate GM-CSF synthesis, suggesting that the CDw17/NF-kappaB/GM-CSF pathway may be beta-glucan-independent. This study provides new insights into the mechanism of GM-CSF induction by C. glabrata.

Candida glabrata prosthetic joint infection, successfully treated with anidulafungin: A case report and review of the literature.

PubMed

Koutserimpas, Christos; Samonis, George; Velivassakis, Emmanouil; Iliopoulou-Kosmadaki, Stylliani; Kontakis, Georgios; Kofteridis, Diamantis P

2018-04-01

Non-albicans Candida prosthetic joint infection (PJI) is extremely rare. A case of a Candida glabrata knee PJI is a 68-year-old splenectomised female smoker, suffering from chronic obstructive pulmonary disease (COPD) and alcoholism is reported. The patient presented with a peri-prosthetic fracture, 15 years after total knee replacement surgery. Cultures of the intraoperative peri-prosthetic tissue and materials yielded C. glabrata, as well as a methicillin-resistant S. epidermitis. The patient was treated with anidulafungin and vancomycin. The knee prosthetic joint was removed and cement-spacer with vancomycin and gentamycin was placed. Additionally, an external fixation was performed. A second stage revision surgery was planned, after completion of the antimicrobial and antifungal treatment. The patient is followed up for 4 months without signs, symptoms or findings of infection. PJI Candida infections require a high clinical suspicion index. It is of utmost importance to report these cases, since there is no consensus yet of the proper antifungal treatment. Furthermore, a literature review regarding treatment of those cases is provided. First-line treatment with an echinocandin seems most proper, due to their fungicidal properties, their effectiveness against biofilm, as well as their minimal toxicity, making them ideal for long-term use. Further experience is needed, for better understanding the disease's pathogenesis and optimal treatment. © 2017 Blackwell Verlag GmbH.

[Susceptibility to azoles and amphotericin B of isolates of Candida spp. Experience of a university health network, between 2004 and 2010].

PubMed

Porte, Lorena; León, Pilar; Gárate, Cynthia; Guzmán, Ana María; Labarca, Jaime; García, Patricia

2012-04-01

To describe antifungal susceptibility testing surveillance (December 2004-September 2010) in Candida spp., for amphotericin B, fluconazole and voriconazole, at the Laboratorio de Microbiología, Pontificia Universidad Católica de Chile. The study was performed utilizing E test and included yeasts from invasive origin and isolates in which antifungal susceptibility testing was asked for by the patient's physician. The yeasts were mainly recovered from urine samples (n: 64), blood cultures (n: 51) and secretions (n: 24). Two hundred ninety three isolates were studied: C. albicans (38%), C. glabrata (30%), C. tropicalis (11%), C. parapsilosis (10%), C. krusei (4%) and others (7%). All Candida species were 100% susceptible to amphotericin B, except C. krusei (1/12). Fluconazole's global susceptibility in C. albicans was 91.8%, but 100% in isolates from blood cultures versus 76% in isolates from urine. C. tropicalis was 93.9% susceptible to fluconazole, C. parapsilosis, 90% and C. glabrata 30.3%. C. krusei had no susceptible isolates to fluconazole. Voriconazole resistance was mainly present in C. glabrata (11.5%). We recommend the study of antifungal susceptibility in isolates from invasive origin, selected urine strains and C. glabrata. Fluconazole remains effective in C. albicans from blood.

[Presumptive identification of Candida spp. and other clinically important yeasts: usefulness of Brilliance Candida Agar].

PubMed

Alfonso, Claudia; López, Mónica; Arechavala, Alicia; Perrone, María Del Carmen; Guelfand, Liliana; Bianchi, Mario

2010-06-30

Fungal infections caused by yeasts have increased during the last decades and invasive forms represent a serious problem for human health. Candida albicans is the species most frequently isolated from clinical samples. However, other emerging yeast pathogens are increasingly responsible for mycotic infections, and some of them are resistant to some antifungal drugs. Consequently, it is necessary to have methods that can provide a rapid presumptive identification at species level. Numerous chromogenic agar media have been shown to be of value as diagnostic tools. We have compared a chromogenic medium, Brilliance Candida Agar, with CHROMagar Candida, the chromogenic medium most used in our country. A multicentre study was conducted in 16 Hospitals belonging to the Mycology Net of Buenos Aires City Government. A total of 240 yeast isolates were included in this research. The new chromogenic agar showed results very similar to those obtained with CHROMagar Candida. Copyright 2009 Revista Iberoamericana de Micología. Published by Elsevier Espana. All rights reserved.

A Novel Hybrid Iron Regulation Network Combines Features from Pathogenic and Nonpathogenic Yeasts.

PubMed

Gerwien, Franziska; Safyan, Abu; Wisgott, Stephanie; Hille, Fabrice; Kaemmer, Philipp; Linde, Jörg; Brunke, Sascha; Kasper, Lydia; Hube, Bernhard

2016-10-18

Iron is an essential micronutrient for both pathogens and their hosts, which restrict iron availability during infections in an effort to prevent microbial growth. Successful human pathogens like the yeast Candida glabrata have thus developed effective iron acquisition strategies. Their regulation has been investigated well for some pathogenic fungi and in the model organism Saccharomyces cerevisiae, which employs an evolutionarily derived system. Here, we show that C. glabrata uses a regulation network largely consisting of components of the S. cerevisiae regulon but also of elements of other pathogenic fungi. Specifically, similarly to baker's yeast, Aft1 is the main positive regulator under iron starvation conditions, while Cth2 degrades mRNAs encoding iron-requiring enzymes. However, unlike the case with S. cerevisiae, a Sef1 ortholog is required for full growth under iron limitation conditions, making C. glabrata an evolutionary intermediate to SEF1-dependent fungal pathogens. Therefore, C. glabrata has evolved an iron homeostasis system which seems to be unique within the pathogenic fungi. The fungus Candida glabrata represents an evolutionarily close relative of the well-studied and benign baker's yeast and model organism Saccharomyces cerevisiae On the other hand, C. glabrata is an important opportunistic human pathogen causing both superficial and systemic infections. The ability to acquire trace metals, in particular, iron, and to tightly regulate this process during infection is considered an important virulence attribute of a variety of pathogens. Importantly, S. cerevisiae uses a highly derivative regulatory system distinct from those of other fungi. Until now, the regulatory mechanism of iron homeostasis in C. glabrata has been mostly unknown. Our study revealed a hybrid iron regulation network that is unique to C. glabrata and is placed at an evolutionary midpoint between those of S. cerevisiae and related fungal pathogens. We thereby

Yeasts from skin colonization are able to cross the acellular dermal matrix.

PubMed

Jarros, Isabele Carrilho; Okuno, Érika; Costa, Maiara Ignacio; Veiga, Flávia Franco; de Souza Bonfim-Mendonça, Patricia; Negri, Melyssa Fernanda Norman; Svidzinski, Terezinha Inez Estivalet

2018-04-01

In recent decades, the prognosis for burn patients has improved considerably with the development of specialized care. The acellular dermal matrix (ADM) is a totally artificial acellular device that functions to control water loss, prevent penetration by bacteria and allow migration of endothelial cells and fibroblasts from patient tissues. However, little is known about its effectiveness against yeasts. The present study evaluated the capacity of colonization and migration of some human commensal yeasts. Three clinical isolates from skin scales, identified as Candida parapsilosis, Candida glabrata and Rhodotorula mucilaginosa, were used. Their ability to cross the ADM was evaluated. After three days, all isolates had crossed the ADM. C. parapsilosis showed the lowest growth, while R. mucilaginosa showed intermediate and C. glabrata the highest growth. In the plates incubated for seven days, the growth of C. parapsilosis and C. glabrata increased by 1 log over the third day. All isolates have the capacity to colonize and migrate through the matrix, increasing the potential risk to burn patients, who can develop severe and even fatal infections by invasive fungi. Copyright © 2018 Elsevier Ltd. All rights reserved.

CE separation of proteins and yeasts dynamically modified by PEG pyrenebutanoate with fluorescence detection.

PubMed

Horká, Marie; Růzicka, Filip; Holá, Veronika; Slais, Karel

2007-07-01

The optimized protocols of the bioanalytes separation, proteins and yeasts, dynamically modified by the nonionogenic tenside PEG pyrenebutanoate, were applied in CZE and CIEF with the acidic gradient in pH range 2-5.5, both with fluorescence detection. PEG pyrenebutanoate was used as a buffer additive for a dynamic modification of proteins and/or yeast samples. The narrow peaks of modified analytes were detected. The values of the pI's of the labeled proteins were calculated using new fluorescent pI markers in CIEF and they were found to be comparable with pI's of the native compounds. As an example of the possible use of the suggested CIEF technique, the mixed cultures of yeasts, Candida albicans, Candida glabrata, Candida kefyr, Candida krusei, Candida lusitaniae, Candida parapsilosis, Candida tropicalis, Candida zeylanoides, Geotrichum candidum, Saccharomyces cerevisiae, Trichosporon asahii and Yarrowia lipolytica, were reproducibly focused and separated with high sensitivity. Using UV excitation for the on-column fluorometric detection, the minimum detectable amounts of analytes, femtograms of proteins and down to ten cells injected on the separation capillary, were estimated.

Techniques for investigation of an apparent outbreak of infections with Candida glabrata.

PubMed Central

Arif, S; Barkham, T; Power, E G; Howell, S A

1996-01-01

A cluster of Candida glabrata isolates recovered from seven patients in an intensive care unit over a 10-week period were compared with a collection of isolates from six epidemiologically distinct outpatients and a reference strain by several DNA typing methods. Restriction enzyme analysis with HinII distinguished 13 strains from the 14 sources and was the method of choice. Pulsed-field gel electrophoresis and random amplification of polymorphic DNA both detected nine types from the 14 sources; however, the results of these two methods did not always correlate. These methods demonstrated that five of the seven patients had distinguishable strains and that cross-infection was unlikely. PMID:8862586

Time to Positivity and Detection of Growth in Anaerobic Blood Culture Vials Predict the Presence of Candida glabrata in Candidemia: a Two-Center European Cohort Study

PubMed Central

Kaasch, Achim J.; Soriano, Alex; Torres, Jorge-Luis; Vergara, Andrea; Morata, Laura; Zboromyrska, Yuliya; De La Calle, Cristina; Alejo, Izaskun; Hernández, Cristina; Cardozo, Celia; Marco, Franscesc; Del Río, Ana; Almela, Manel; Mensa, Josep; Martínez, José Antonio

2014-01-01

This study shows the accuracy of exclusive or earlier growth in anaerobic vials to predict Candida glabrata in a large series of candidemic patients from two European hospitals using the Bactec 9240 system. Alternatively, C. glabrata can be predicted by a time to positivity cutoff value, which should be determined for each setting. PMID:24899027

Candida dajiaensis sp. nov., Candida yuanshanicus sp. nov., Candida jianshihensis sp. nov., and Candida sanyiensis sp. nov., four anamorphic, ascomycetous yeast species isolated from soil in Taiwan.

PubMed

Liu, Chun-Hao; Young, Shuh-Sen; Chang, Tsung-Chain; Lee, Ching-Fu

2008-08-01

Nine anamorphic, ascomycetous yeast strains belonging to the Pichia anomala clade were recovered from forest soil in 2006 in Taiwan. The nine yeast strains represent four novel yeast species based on the sequences of their D1/D2 domain of the large subunit (LSU) rRNA gene and their physiological characteristics. The scientific names of Candida dajiaensis sp. nov., Candida yuanshanicus sp. nov., Candida jianshihensis sp. nov., and Candida sanyiensis sp. nov. are proposed for these novel yeast species. The type strains are C. dajiaensis SM11S03(T) (=CBS 10590(T)=BCRC 23099(T)), C. yuanshanicus SY3S02(T) (=CBS 10589(T)=BCRC 23100(T)), C. jianshihensis SM8S04(T) (=CBS 10591(T)=BCRC 23096(T)), and C. sanyiensis SA1S06(T) (=CBS 10592(T)=BCRC 23094(T)). Sequence analysis of the D1/D2 of the LSU rRNA gene revealed that the three species, C. dajiaensis, C. yuanshanicus and Pichia onychis, shared a separate branch in the phylogenetic tree, C. jianshihensis is phylogenetically related to Candida ulmi and Pichia alni, and the phylogenetically closest relative of C. sanyiensis is Pichia populi.

Antifungal susceptibilities of Candida, Cryptococcus neoformans and Aspergillus fumigatus from the Asia and Western Pacific region: data from the SENTRY antifungal surveillance program (2010-2012).

PubMed

Pfaller, Michael A; Messer, Shawn A; Jones, Ronald N; Castanheira, Mariana

2015-09-01

The SENTRY Antifungal Surveillance Program monitors global susceptibility rates of newer and established antifungal agents. We report the in vitro activity of seven antifungal agents against 496 contemporary clinical isolates of yeasts and molds. The isolates were obtained from 20 laboratories in the Asia-Western Pacific (APAC) region during 2010 through 2012. Anidulafungin, caspofungin, micafungin, fluconazole, itraconazole, posaconazole and voriconazole were susceptibility tested using CLSI methods and species-specific interpretive criteria. Sequencing of fks hot spots was performed for echinocandin-resistant strains. Isolates included 13 species of Candida (n=460), 5 species of non-Candida yeasts (21), 5 species of Aspergillus (11) and 4 other molds. Echinocandin resistance was uncommon among eight species of Candida and was only detected in three isolates of Candida glabrata, two from Australia harboring mutations in fks1 (F625S) and fks2 (S663P). Resistance to the azoles was much more common and was observed among all species with the exception of Candida dubliniensis. Fluconazole resistance rates observed with C. glabrata (6.8%) was comparable to that seen with Candida parapsilosis (5.7%) and Candida tropicalis (3.6%). Cross resistance among the triazoles was seen with each of these three species. The mold-active azoles and the echinocandins were all active against isolates of Aspergillus fumigatus. Azole resistance was not detected among the isolates of Cryptococcus neoformans. Antifungal resistance is uncommon among isolates of fungi causing invasive fungal infections in the APAC region. As in other regions of the world, emerging resistance to the echinocandins among invasive isolates of C. glabrata bears close monitoring.

Prevalence of Candida bracarensis and Candida nivariensis in a Spanish collection of yeasts: comparison of results from a reference centre and from a population-based surveillance study of candidemia.

PubMed

Cuenca-Estrella, M; Gomez-Lopez, A; Isla, G; Rodriguez, D; Almirante, B; Pahissa, A; Rodriguez-Tudela, J L

2011-07-01

Two new species related to Candida glabrata, i.e., Candida nivariensis and Candida bracarensis, have been proposed. The occurrence of these species among isolates collected in a Spanish mycology reference laboratory in 2008-2009 was reviewed. In addition, strains recovered as part of an active population-based surveillance of candidemia conducted in Barcelona between 2002 and 2003 were also analyzed. Among 143 clinical isolates received in 2008-2009, three (2%) were identified as C. bracarensis and none as C. nivariensis through sequencing of their ribosomal DNA. Of the 31 strains initially identified as C. glabrata in the 2002-2003 population-based study (0.38 cases/100,000 population), none were found to belong to these related new species. Results from in vitro susceptibility studies of C. bracarensis isolates were comparable to those found with C. glabrata. Since new and cryptic species have been described, periodic surveillance including the use of molecular identification methods seems to be necessary in order to determine their frequency, geographical distribution and susceptibility profile.

Growth, biofilm formation, antifungal susceptibility and oxidative stress resistance of Candida glabrata are affected by different glucose concentrations.

PubMed

Ng, Tzu Shan; Desa, Mohd Nasir Mohd; Sandai, Doblin; Chong, Pei Pei; Than, Leslie Thian Lung

2016-06-01

Glucose is an important fuel source to support many living organisms. Its importance in the physiological fitness and pathogenicity of Candida glabrata, an emerging human fungal pathogen has not been extensively studied. The present study aimed to investigate the effects of glucose on the growth, biofilm formation, antifungal susceptibility and oxidative stress resistance of C. glabrata. In addition, its effect on the expression of a putative high affinity glucose sensor gene, SNF3 was also investigated. Glucose concentrations were found to exert effects on the physiological responses of C. glabrata. The growth rate of the species correlated positively to the amount of glucose. In addition, low glucose environments were found to induce C. glabrata to form biofilm and resist amphotericin B. Conversely, high glucose environments promoted oxidative stress resistance of C. glabrata. The expression of CgSNF3 was found to be significantly up-regulated in low glucose environments. The expression of SNF3 gene in clinical isolates was found to be higher compared to ATCC laboratory strains in low glucose concentrations, which may explain the better survivability of clinical isolates in the low glucose environment. These observations demonstrated the impact of glucose in directing the physiology and virulence fitness of C. glabrata through the possible modulation by SNF3 as a glucose sensor, which in turn aids the species to adapt, survive and thrive in hostile host environment. Copyright © 2015 Elsevier B.V. All rights reserved.

Segregation and transmission of mitochondrial markers in fusion products of the asporogenous yeast Torulopsis glabrata.

PubMed

Sriprakash, K S; Batum, C

1981-09-01

Using a protoplast fusion technique we have been able to locate to the mitochondrial genome of the asporogenous yeast Torulopsis glabrata mutations conferring resistance to oligomycin, antimycin and diuron. When two strains differing in the size of their mtDNAs were fused the mitochondrial markers from the parent with the larger mtDNA (71-91) were transmitted predominantly among the fusion products. Both genetical and physical evidence support the occurrence of recombination in T. glabrata mitochondrial genome. Segregation of the mitochondrial genome appears to take place before the separation of the first bud from the fusion product.

Presence of Candida spp. in the oral cavity of heart transplantation patients

PubMed Central

RIBEIRO, Patrícia Monteiro; BACAL, Fernando; KOGA-ITO, Cristiane Yumi; JUNQUEIRA, Juliana Campos; JORGE, Antonio Olavo Cardoso

2011-01-01

Candida spp. can lead to infections or even fungal sepsis particularly among immunocompromized individuals. Objective The aim of the present study was to analyze the presence of Candida spp. among patients subjected to orthotopic heart transplantation. Material and Methods Oral rinses from 50 patients subjected to orthotopic heart transplantation, aged 13 to 70 years, 40 males and 10 females, were examined. Sexage-oral conditions matched-control included 50 individuals who were not subjected to any kind of transplantation and were not immunocompromized for any other reason. Counts of yeasts were expressed as median values of logarithm of cfu/mL and were statistically compared by Mann-Whitney’s test. The heart transplant and control groups were compared for the presence of Candida spp. by chi-square test (p<0.05). Results The results showed statistically significant difference (p=0.001) in the prevalence of Candida spp. between the transplantation and control groups. Counts of yeasts (cfu/mL) in the transplanted group were significantly higher than in the control group (p=0.005). Candida albicans was the most prevalent species isolated from both groups. Conclusion It was concluded that Candida yeast counts were higher in the heart transplant recipients than in the controls. There was higher variation of Candida species among the heart transplant patients and the most frequently isolated samples were: Candida albicans, Candida glabrata and Candida tropicalis. Isolates of Candida dubliniensis was not found in either of the groups. PMID:21437462

Time to positivity and detection of growth in anaerobic blood culture vials predict the presence of Candida glabrata in candidemia: a two-center European cohort study.

PubMed

Cobos-Trigueros, Nazaret; Kaasch, Achim J; Soriano, Alex; Torres, Jorge-Luis; Vergara, Andrea; Morata, Laura; Zboromyrska, Yuliya; De La Calle, Cristina; Alejo, Izaskun; Hernández, Cristina; Cardozo, Celia; Marco, Franscesc; Del Río, Ana; Almela, Manel; Mensa, Josep; Martínez, José Antonio

2014-08-01

This study shows the accuracy of exclusive or earlier growth in anaerobic vials to predict Candida glabrata in a large series of candidemic patients from two European hospitals using the Bactec 9240 system. Alternatively, C. glabrata can be predicted by a time to positivity cutoff value, which should be determined for each setting. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Identification of uncommon oral yeasts from cancer patients by MALDI-TOF mass spectrometry.

PubMed

Aslani, Narges; Janbabaei, Ghasem; Abastabar, Mahdi; Meis, Jacques F; Babaeian, Mahasti; Khodavaisy, Sadegh; Boekhout, Teun; Badali, Hamid

2018-01-08

Opportunistic infections due to Candida species occur frequently in cancer patients because of their inherent immunosuppression. The aim of the present study was to investigate the epidemiology of yeast species from the oral cavity of patients during treatment for oncological and haematological malignancies. MALDI-TOF was performed to identify yeasts isolated from the oral cavity of 350 cancer patients. Moreover, antifungal susceptibility testing was performed in according to CLSI guidelines (M27-A3). Among 162 yeasts and yeast-like fungi isolated from the oral cavity of cancer patients, Candida albicans was the most common species (50.6%), followed by Candida glabrata (24.7%), Pichia kudriavzevii (Candida krusei (9.9%)), Candida tropicalis (4.3%), Candida dubliniensis (3.7%), Kluyveromyces marxianus (Candida kefyr (3.7%)) and Candida parapsilosis (1%). In addition, uncommon yeast species i.e., Saprochaete capitata, Saccharomyces cerevisiae, Clavispora lusitaniae (C. lusitaniae) and Pichia kluyveri (C. eremophila) were recovered from oral lesions. Oral colonization by C. albicans, non-albicans Candida species and uncommon yeasts were as follow; 55%, 44% and 1%, whereas oral infection due to C. albicans was 33.3%, non-albicans Candida species 60.6%, and uncommon yeasts 6.1%. Poor oral hygiene and xerostomia were identified as independent risk factors associated with oral yeast colonization. The overall resistance to fluconazole was 11.7% (19/162). Low MIC values were observed for anidulafungin for all Candida and uncommon yeast species. This current study provides insight into the prevalence and susceptibility profiles of Candida species, including emerging Candida species and uncommon yeasts, isolated from the oral cavity of Iranian cancer patients. The incidence of oral candidiasis was higher amongst patients with hematological malignancies. The majority of oral infections were caused by non-albicans Candida species which were often more resistant to anti

Multi-drug resistant oral Candida species isolated from HIV-positive patients in South Africa and Cameroon.

PubMed

Dos Santos Abrantes, Pedro Miguel; McArthur, Carole P; Africa, Charlene Wilma Joyce

2014-06-01

Candida species are a common cause of infection in immune-compromised HIV-positive individuals, who are usually treated with the antifungal drug, fluconazole, in public hospitals in Africa. However, information about the prevalence of drug resistance to fluconazole and other antifungal agents on Candida species is very limited. This study examined 128 Candida isolates from South Africa and 126 Cameroonian Candida isolates for determination of species prevalence and antifungal drug susceptibility. The isolates were characterized by growth on chromogenic and selective media and by their susceptibility to 9 antifungal drugs tested using the TREK™ YeastOne9 drug panel (Thermo Scientific, USA). Eighty-three percent (82.8%) of South African isolates were Candida albicans (106 isolates), 9.4% were Candida glabrata (12 isolates), and 7.8% were Candida dubliniensis (10 isolates). Of the Cameroonian isolates, 73.02% were C. albicans (92 isolates); 19.05% C. glabrata (24 isolates); 3.2% Candida tropicalis (4 isolates); 2.4% Candida krusei (3 isolates); 1.59% either Candida kefyr, Candida parapsilopsis, or Candida lusitaneae (2 isolates); and 0.79% C. dubliniensis (1 isolate). Widespread C. albicans resistance to azoles was detected phenotypically in both populations. Differences in drug resistance were seen within C. glabrata found in both populations. Echinocandin drugs were more effective on isolates obtained from the Cameroon than in South Africa. A multiple-drug resistant C. dubliniensis strain isolated from the South African samples was inhibited only by 5-flucytosine in vitro on the YO9 panel. Drug resistance among oral Candida species is common among African HIV patients in these 2 countries. Regional surveillance of Candida species drug susceptibility should be undertaken to ensure effective treatment for HIV-positive patients. Copyright © 2014 Elsevier Inc. All rights reserved.

Candida laoshanensis sp. nov. and Candida qingdaonensis sp. nov., anamorphic, ascomycetous yeast species isolated from decayed wood.

PubMed

Wang, Shi-An; Li, Fu-Li; Bai, Feng-Yan

2010-07-01

During a study of newly isolated yeast strains utilizing d-xylose as sole carbon source, eight strains, isolated from decayed wood, were found to represent two novel anamorphic, ascomycetous yeast species based on sequence analysis of the 26S rDNA D1/D2 domain and internal transcribed spacer region, and phenotypic characterization. The names Candida laoshanensis sp. nov. (type strain MLRW 6-2(T)=AS 2.4030(T)=CBS 11389(T)) and Candida qingdaonensis sp. nov. (type strain MLRW 7-1(T)=AS 2.4031(T)=CBS 11390(T)) are proposed for these two novel species; the closest relatives of the two novel species are Candida pomicola and Candida marilandica, respectively.

Effects of antifungal agents alone and in combination against Candida glabrata strains susceptible or resistant to fluconazole.

PubMed

Alves, Izabel Almeida; Bandeira, Laíssa Arévalo; Mario, Débora Alves Nunes; Denardi, Laura Bedin; Neves, Louise Vignoles; Santurio, Janio Morais; Alves, Sydney Hartz

2012-09-01

The rise of Candida spp. resistant to classic triazole antifungal agents has led to a search for new therapeutic options. Here, we evaluated combinations of antifungals in a checkerboard assay against two groups of Candida glabrata strains: one containing fluconazole-susceptible clinical isolates (FS) and another containing fluconazole-resistant laboratory derivative (FR). The most synergistic combination observed was amphotericin B + flucytosine (synergistic for 61.77 % of FS strains and 76.47 % of FR strains). The most antagonistic combination observed was ketoconazole + flucytosine (FS 61.77 % and FR 55.88 %). Surprisingly, most combinations evidenced indifferent interactions, and the best synergism appeared when amphotericin B and flucytosine were combined against both groups of isolates.

Facultative Sterol Uptake in an Ergosterol-Deficient Clinical Isolate of Candida glabrata Harboring a Missense Mutation in ERG11 and Exhibiting Cross-Resistance to Azoles and Amphotericin B

PubMed Central

Hull, Claire M.; Parker, Josie E.; Bader, Oliver; Weig, Michael; Gross, Uwe; Warrilow, Andrew G. S.; Kelly, Diane E.

2012-01-01

We identified a clinical isolate of Candida glabrata (CG156) exhibiting flocculent growth and cross-resistance to fluconazole (FLC), voriconazole (VRC), and amphotericin B (AMB), with MICs of >256, >256, and 32 μg ml−1, respectively. Sterol analysis using gas chromatography-mass spectrometry (GC-MS) revealed that CG156 was a sterol 14α-demethylase (Erg11p) mutant, wherein 14α-methylated intermediates (lanosterol was >80% of the total) were the only detectable sterols. ERG11 sequencing indicated that CG156 harbored a single-amino-acid substitution (G315D) which nullified the function of native Erg11p. In heterologous expression studies using a doxycycline-regulatable Saccharomyces cerevisiae erg11 strain, wild-type C. glabrata Erg11p fully complemented the function of S. cerevisiae sterol 14α-demethylase, restoring growth and ergosterol synthesis in recombinant yeast; mutated CG156 Erg11p did not. CG156 was culturable using sterol-free, glucose-containing yeast minimal medium (glcYM). However, when grown on sterol-supplemented glcYM (with ergosta 7,22-dienol, ergosterol, cholestanol, cholesterol, Δ7-cholestenol, or desmosterol), CG156 cultures exhibited shorter lag phases, reached higher cell densities, and showed alterations in cellular sterol composition. Unlike comparator isolates (harboring wild-type ERG11) that became less sensitive to FLC and VRC when cultured on sterol-supplemented glcYM, facultative sterol uptake by CG156 did not affect its azole-resistant phenotype. Conversely, CG156 grown using glcYM with ergosterol (or with ergosta 7,22-dienol) showed increased sensitivity to AMB; CG156 grown using glcYM with cholesterol (or with cholestanol) became more resistant (MICs of 2 and >64 μg AMB ml−1, respectively). Our results provide insights into the consequences of sterol uptake and metabolism on growth and antifungal resistance in C. glabrata. PMID:22615281

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

PubMed Central

de Oliveira, Jean Carlos Almeida

2017-01-01

Candida glabrata is a facultative intracellular opportunistic fungal pathogen in human infections. Several virulence-associated attributes are involved in its pathogenesis, host-pathogen interactions, modulation of host immune defenses, and regulation of antifungal drug resistance. This study evaluated the in vitro antifungal susceptibility profile to five antifungal agents, the production of seven hydrolytic enzymes related to virulence, and the relationship between these phenotypes in 91 clinical strains of C. glabrata. All C. glabrata strains were susceptible to flucytosine. However, some of these strains showed resistance to amphotericin B (9.9%), fluconazole (15.4%), itraconazole (5.5%), or micafungin (15.4%). Overall, C. glabrata strains were good producers of catalase, aspartic protease, esterase, phytase, and hemolysin. However, caseinase and phospholipase in vitro activities were not detected. Statistically significant correlations were identified between micafungin minimum inhibitory concentration (MIC) and esterase production, between fluconazole and micafungin MIC and hemolytic activity, and between amphotericin B MIC and phytase production. These results contribute to clarify some of the C. glabrata mechanisms of pathogenicity. Moreover, the association between some virulence attributes and the regulation of antifungal resistance encourage the development of new therapeutic strategies involving virulence mechanisms as potential targets for effective antifungal drug development for the treatment of C. glabrata infections. PMID:28814823

Pigeons and their droppings as reservoirs of Candida and other zoonotic yeasts.

PubMed

Rosario Medina, Inmaculada; Román Fuentes, Lorena; Batista Arteaga, Miguel; Real Valcárcel, Fernando; Acosta Arbelo, Félix; Padilla Del Castillo, Daniel; Déniz Suárez, Soraya; Ferrer Quintana, Otilia; Vega Gutiérrez, Belinda; Silva Sergent, Freddy; Acosta-Hernández, Begoña

The importance of pigeons as reservoirs and carriers of Cryptococcus neoformans and other species of this genus is well-known; however, less is known about their role as reservoirs and carriers of other yeasts that impact public health. The present study was performed on Gran Canaria Island to define yeasts other than Cryptococcus spp. that have been reported to impact public health and which could be carried by pigeons. Samples were obtained from 83 pigeon lofts (Columba livia); moreover, 331 crop samples, 331 cloacal samples and 174 dropping samples were collected. In addition, 17 dropping samples were taken from a total of 17 public squares. Samples were inoculated on Sabouraud dextrose agar with chloramphenicol. Different yeast species, i.e. Candida guilliermondii (24.36%), Candida kefyr (1.21%), Saccharomyces cerevisiae (2.43%), and Trichosporon asahii (1.21%) were isolated for the first time from the cloaca. The most frequently isolated yeast from the crop, cloaca and dropping samples from lofts was C. guilliermondii (30.46%, 24.36% and 49.37%, respectively). In addition, for the first time, C. kefyr (3.65%), Candida pelliculosa (2.43%), Candida rugosa (1.21%), T. asahii (3.65%), Trichosporon mucoides (3.65%) and Prototheca wickerhamii (1.21%) were obtained from crop samples; Candida pelliculosa (1.20%), T. asahii (9.63%) and T. mucoides (7.22%) were isolated from dropping samples in the lofts. Candida albicans was the most frequently isolated yeast in dropping samples collected in public squares. It can be assumed that pigeons and their droppings act as carriers and reservoirs of Candida spp. and other zoonotic yeasts. Copyright © 2017 Asociación Española de Micología. Publicado por Elsevier España, S.L.U. All rights reserved.

[Onychomycosis by yeast not common in diabetics of a health center].

PubMed

Imbert, J L; G Gomez, J V; Escudero, R B; Blasco, J L

2016-10-01

Mexican diabetic population frequently presents mycosis under foot hyperkeratosis; however, in another type of onychomycosis as the ones that is assumed Candida albicans is the causal agent, it is unknown the frequency, the prevalence and if another Candida species or other yeasts are found. Evaluate the frequency of yeasts causing onychomycosis in diabetic patients looked after in public institutions of health of the State of Hidalgo, Mexico, and its association with clinical epidemiological variables. An observational, descriptive and transversal study was made on 261 patients, from which one nail sample of each one was obtained, used to isolate and identify dermatophytes and yeasts; the results were statistically correlated with 24 epidemiological parameters. The clinical study was done through interrogation and by medical exploration in order to evaluate Tinea pedis and onychomycosis. Onychomycosis were caused by Candida guilliermondii, Candida parapsilosis, Candida glabrata, Candida krusei, Candida spp., Kodamaea ohmeri, Prototheca wickerhamii and unidentified yeasts. The prevalence for general onychomycosis, by dermatophytes, mixed onychomycosis and by yeasts were: 24.1, 19.5, 2.3 and 14.6%, respectively. Patients with significant probability to be diagnosed as having onychomycosis by yeasts are those wearing open shoes (2.59%); technicians and professionals (10.49%) and alcohol drinkers (3.72%). The fact that Candida albicans is not present in this study as causal agent of onychomycosis, and emerging and non-common yeasts were indeed isolated, creates new challenges. It is remarked the clinical criterion that when onychomycosis is suspected in diabetics, the diagnosis for culturing dermatophytes and yeasts should be included. Copyright © 2015 Sociedad Española de Médicos de Atención Primaria (SEMERGEN). Publicado por Elsevier España, S.L.U. All rights reserved.

Multicenter Study of Epidemiological Cutoff Values and Detection of Resistance in Candida spp. to Anidulafungin, Caspofungin, and Micafungin Using the Sensititre YeastOne Colorimetric Method

PubMed Central

Alvarez-Fernandez, M.; Cantón, E.; Carver, P. L.; Chen, S. C.-A.; Eschenauer, G.; Getsinger, D. L.; Gonzalez, G. M.; Grancini, A.; Hanson, K. E.; Kidd, S. E.; Klinker, K.; Kubin, C. J.; Kus, J. V.; Lockhart, S. R.; Meletiadis, J.; Morris, A. J.; Pelaez, T.; Rodriguez-Iglesias, M.; Sánchez-Reus, F.; Shoham, S.; Wengenack, N. L.; Borrell Solé, N.; Echeverria, J.; Esperalba, J.; Gómez-G. de la Pedrosa, E.; García García, I.; Linares, M. J.; Marco, F.; Merino, P.; Pemán, J.; Pérez del Molino, L.; Roselló Mayans, E.; Rubio Calvo, C.; Ruiz Pérez de Pipaon, M.; Yagüe, G.; Garcia-Effron, G.; Perlin, D. S.; Sanguinetti, M.; Shields, R.; Turnidge, J.

2015-01-01

Neither breakpoints (BPs) nor epidemiological cutoff values (ECVs) have been established for Candida spp. with anidulafungin, caspofungin, and micafungin when using the Sensititre YeastOne (SYO) broth dilution colorimetric method. In addition, reference caspofungin MICs have so far proven to be unreliable. Candida species wild-type (WT) MIC distributions (for microorganisms in a species/drug combination with no detectable phenotypic resistance) were established for 6,007 Candida albicans, 186 C. dubliniensis, 3,188 C. glabrata complex, 119 C. guilliermondii, 493 C. krusei, 205 C. lusitaniae, 3,136 C. parapsilosis complex, and 1,016 C. tropicalis isolates. SYO MIC data gathered from 38 laboratories in Australia, Canada, Europe, Mexico, New Zealand, South Africa, and the United States were pooled to statistically define SYO ECVs. ECVs for anidulafungin, caspofungin, and micafungin encompassing ≥97.5% of the statistically modeled population were, respectively, 0.12, 0.25, and 0.06 μg/ml for C. albicans, 0.12, 0.25, and 0.03 μg/ml for C. glabrata complex, 4, 2, and 4 μg/ml for C. parapsilosis complex, 0.5, 0.25, and 0.06 μg/ml for C. tropicalis, 0.25, 1, and 0.25 μg/ml for C. krusei, 0.25, 1, and 0.12 μg/ml for C. lusitaniae, 4, 2, and 2 μg/ml for C. guilliermondii, and 0.25, 0.25, and 0.12 μg/ml for C. dubliniensis. Species-specific SYO ECVs for anidulafungin, caspofungin, and micafungin correctly classified 72 (88.9%), 74 (91.4%), 76 (93.8%), respectively, of 81 Candida isolates with identified fks mutations. SYO ECVs may aid in detecting non-WT isolates with reduced susceptibility to anidulafungin, micafungin, and especially caspofungin, since testing the susceptibilities of Candida spp. to caspofungin by reference methodologies is not recommended. PMID:26282428

Performance of Chromogenic Candida agar and CHROMagar Candida in recovery and presumptive identification of monofungal and polyfungal vaginal isolates.

PubMed

Ozcan, Kadri; Ilkit, Macit; Ates, Aylin; Turac-Bicer, Aygul; Demirhindi, Hakan

2010-02-01

Chromogenic Candida agar (OCCA) is a novel medium facilitating isolation and identification of Candida albicans, C. tropicalis, and C. krusei, as well as indicating polyfungal population in clinical samples. We compare the performance of OCCA, to CHROMagar Candida (CAC) and Sabouraud chloramphenicol agar (SCA). Vaginal swab samples from 392 women were simultaneously inoculated onto three study media. A total of 161 (41.1%) were found to be positive for fungi of which 140 (87%) were monofungal, and 21 (13%) polyfungal. One-hundred and fifty-seven samples (97.5%) were positive on CAC, 156 (96.9%) on OCCA, 148 (91.9%) on SCA and 144 (89.4%) samples were positive on all three media. The yeasts were identified by conventional methods including germ tube test, microscopic morphology on cornmeal-Tween 80 agar, and the commercial API 20C AUX. The 182 isolates were C. albicans (n = 104), C. glabrata (n = 51), C. krusei (n = 7), C. tropicalis (n = 5), C. famata (n = 3), C. kefyr (n = 3), C. zeylanoides (n = 3), C. colliculosa (n = 2), and other species of Candida (n = 4). Among the 21 polyfungal populations, 20 (95.2%) were detected in OCCA, 14 (66.7%) in CAC, and 13 (61.9%) in CAC and OCCA (P <0.05). Most polyfungal populations (47.6%) yielded C. albicans + C. glabrata. The efficiency of both chromogenic media for C. albicans was >or=92.9% at 72 h. OCCA is more efficient and reliable for rapidly identifying C. albicans and polyfungal populations than CAC. However, CAC is more efficient for identifying C. krusei and C. tropicalis. A chromogenic agar with a higher isolation rate of yeasts and better detection of polyfungal populations than SCA, is suggested as a medium of first choice when available.

Oral yeast carriage in HIV-infected and non-infected populations in Rosario, Argentina.

PubMed

Luque, A G; Biasoli, M S; Tosello, M E; Binolfi, A; Lupo, S; Magaró, H M

2009-01-01

The objectives of the present study were: (i) to assess the frequency of oral colonisation by Candida species in HIV-positive patients and to compare it with a population of HIV-negative individuals, (ii) to determine the prevalence of C. dubliniensis in both populations and (iii) to determine the susceptibility of C. dubliniensis and other Candida species isolated from HIV-positive patients to the most commonly used antifungal agents. Oral samples were obtained from 101 HIV-positive and 108 HIV-negative subjects. For yeast identification, we used morphology in cornmeal agar, the API 20C Aux, growth at 45 degrees C, d-xylose assimilation, morphology in sunflower seed agar and PCR. The frequency of isolation of Candida in HIV-positive patients was: C. albicans, 60.7%; C. dubliniensis, 20.2%; C. glabrata, 5.6%; C. krusei, 5.6%; C. tropicalis, 4.5%; others, <5%. The frequency of isolation of Candida in HIV-negative patients was: C. albicans, 73.9%; C. tropicalis, 15.5%; C. dubliniensis, 2.1%; C. glabrata, 2.1%; C. parapsilosis, 2.1%; others, <5%. The oral colonisation by yeast in the HIV-positive patients was higher than that in the HIV-negative subjects. The susceptibilities of 42 Candida isolates to three antifungal agents were determined. All isolates of C. dubliniensis were susceptible to fluconazole, although several individuals had been previously treated with this drug. Out of the 42 Candida isolates, 10 presented resistance to fluconazole and 10 to itraconazole. The presence of Candida species, resistant to commonly used antifungal agents, represents a potential risk in immunocompromised patients.

Production of ethanol from infant food formulas by common yeasts.

PubMed

Bivin, W S; Heinen, B N

1985-04-01

Four common yeasts (Candida albicans, Candida tropicalis, Torulopsis glabrata and Saccharomyces cerevisiae) were combined with five infant food formulas and/or supplements (Isomil, Nutramigen, 5% glucose, Coca Cola and Similac) and incubated at 37 degrees C. Gas chromatography was used to measure ethanol production after 24 and 48 h incubation. The quantities of ethanol produced suggest a possible explanation for patients exhibiting the 'Auto-Brewery Syndrome' and raises interest in the role auto-produced ethanol could have in explaining the etiology of Sudden Infant Death.

Prevalence & susceptibility to fluconazole of Candida species causing vulvovaginitis.

PubMed

Mohanty, Srujana; Xess, Immaculata; Hasan, Fahmi; Kapil, Arti; Mittal, Suneeta; Tolosa, Jorge E

2007-09-01

Vulvovaginal candidiasis is an important cause of morbidity in women of reproductive age. This study was carried out to determine the species prevalence and susceptibility pattern to fluconazole of yeasts isolated from the vagina of symptomatic women. This prospective study was conducted in a rural primary health care center of north India from May 2003 to April 2004 and included 601 married, sexually active women (18-49 yr) with the self reported symptoms of vaginal discharge and/or genital itching and/or genital burning. Specific aetiology of the genitourinary symptoms including candidal infection were determined. Specimens from the lateral wall of vagina were subjected to direct wet mount microscopy and fungal culture on Sabouraud's dextrose agar. Susceptibility testing to fluconazole was carried out using broth microdilution method. Yeasts were isolated in 111 (18.5%) women and these consisted of Candida glabrata (56, 50.4%), C. albicans (39, 35.1%), C. tropicalis (12, 10.8%), C. krusei (3, 2.7%) and C. parapsilosis (1, 0.9%). Susceptibility testing carried out on 30 representative isolates (15 C. glabrata, 10 C. albicans, 4 C. tropicalis and 1 C. parapsilosis) revealed that 21 isolates (70%) were susceptible (MIC, < or = 8 microg/ml) to fluconazole while 9 (30%) were susceptible-dose dependent (S-DD, MIC 16-32 microg/ml). Our findings suggest a low prevalence of fluconazole resistance in vaginal candida isolates in our population. However, a high prevalence of non-albicans candida species and increased dose-dependent resistance in these isolates necessitates vigilance since this may warrant a change in the optimal therapy of non-albicans candida vaginitis.

Yeast diversity associated to sediments and water from two Colombian artificial lakes

PubMed Central

Silva-Bedoya, L.M.; Ramírez-Castrillón, M.; Osorio-Cadavid, E.

2014-01-01

In Colombia, knowledge of the yeast and yeast-like fungi community is limited because most studies have focused on species with clinical importance. Sediments and water represent important habitats for the study of yeast diversity, especially for yeast species with industrial, biotechnological, and bioremediation potential. The main purpose of this study was to identify and compare the diversity of yeast species associated with sediment and water samples from two artificial lakes in Universidad del Valle (Cali-Colombia). Yeast samplings were performed from fifteen sediment samples and ten water samples. Grouping of similar isolates was initially based on colony and cell morphology, which was then complemented by micro/mini satellite primed PCR banding pattern analysis by using GTG5 as single primer. A representative isolate for each group established was chosen for D1/D2 domain sequencing and identification. In general, the following yeast species were identified: Candida albicans, Candida diversa, Candida glabrata, Candida pseudolambica, Cryptococcus podzolicus, Cryptococcus rajasthanensis, Cryptococcus laurentii, Williopsis saturnus, Hanseniaspora thailandica, Hanseniaspora uvarum, Rhodotorula mucilaginosa, Saccharomyces cerevisiae, Torulaspora delbrueckii, Torulaspora pretoriensis, Tricosporon jirovecii, Trichosporon laibachii and Yarrowia lypolitica. Two possible new species were also found, belonging to the Issatchenkia sp. and Bullera sp. genera. In conclusion, the lakes at the Universidad del Valle campus have significant differences in yeast diversity and species composition between them. PMID:24948924

A Novel Hybrid Iron Regulation Network Combines Features from Pathogenic and Nonpathogenic Yeasts

PubMed Central

Gerwien, Franziska; Safyan, Abu; Wisgott, Stephanie; Hille, Fabrice; Kaemmer, Philipp; Linde, Jörg; Brunke, Sascha; Kasper, Lydia

2016-01-01

ABSTRACT Iron is an essential micronutrient for both pathogens and their hosts, which restrict iron availability during infections in an effort to prevent microbial growth. Successful human pathogens like the yeast Candida glabrata have thus developed effective iron acquisition strategies. Their regulation has been investigated well for some pathogenic fungi and in the model organism Saccharomyces cerevisiae, which employs an evolutionarily derived system. Here, we show that C. glabrata uses a regulation network largely consisting of components of the S. cerevisiae regulon but also of elements of other pathogenic fungi. Specifically, similarly to baker’s yeast, Aft1 is the main positive regulator under iron starvation conditions, while Cth2 degrades mRNAs encoding iron-requiring enzymes. However, unlike the case with S. cerevisiae, a Sef1 ortholog is required for full growth under iron limitation conditions, making C. glabrata an evolutionary intermediate to SEF1-dependent fungal pathogens. Therefore, C. glabrata has evolved an iron homeostasis system which seems to be unique within the pathogenic fungi. PMID:27795405

Rapid Identification of Candida Species by Using Nuclear Magnetic Resonance Spectroscopy and a Statistical Classification Strategy

PubMed Central

Himmelreich, Uwe; Somorjai, Ray L.; Dolenko, Brion; Lee, Ok Cha; Daniel, Heide-Marie; Murray, Ronan; Mountford, Carolyn E.; Sorrell, Tania C.

2003-01-01

Nuclear magnetic resonance (NMR) spectra were acquired from suspensions of clinically important yeast species of the genus Candida to characterize the relationship between metabolite profiles and species identification. Major metabolites were identified by using two-dimensional correlation NMR spectroscopy. One-dimensional proton NMR spectra were analyzed by using a staged statistical classification strategy. Analysis of NMR spectra from 442 isolates of Candida albicans, C. glabrata, C. krusei, C. parapsilosis, and C. tropicalis resulted in rapid, accurate identification when compared with conventional and DNA-based identification. Spectral regions used for the classification of the five yeast species revealed species-specific differences in relative amounts of lipids, trehalose, polyols, and other metabolites. Isolates of C. parapsilosis and C. glabrata with unusual PCR fingerprinting patterns also generated atypical NMR spectra, suggesting the possibility of intraspecies discontinuity. We conclude that NMR spectroscopy combined with a statistical classification strategy is a rapid, nondestructive, and potentially valuable method for identification and chemotaxonomic characterization that may be broadly applicable to fungi and other microorganisms. PMID:12902244

Yeast microbiota of natural cavities of manatees (Trichechus inunguis and Trichechus manatus) in Brazil and its relevance for animal health and management in captivity.

PubMed

Sidrim, José Júlio Costa; Carvalho, Vitor Luz; Castelo-Branco, Débora de Souza Collares Maia; Brilhante, Raimunda Sâmia Nogueira; Bandeira, Tereza de Jesus Pinheiro Gomes; Cordeiro, Rossana de Aguiar; Guedes, Gláucia Morgana de Melo; Barbosa, Giovanna Riello; Lazzarini, Stella Maris; Oliveira, Daniella Carvalho Ribeiro; de Meirelles, Ana Carolina Oliveira; Attademo, Fernanda Löffler Niemeyer; Freire, Augusto Carlos da Bôaviagem; Moreira, José Luciano Bezerra; Monteiro, André Jalles; Rocha, Marcos Fábio Gadelha

2015-10-01

The aim of this study was to characterize the yeast microbiota of natural cavities of manatees kept in captivity in Brazil. Sterile swabs from the oral cavity, nostrils, genital opening, and rectum of 50 Trichechus inunguis and 26 Trichechus manatus were collected. The samples were plated on Sabouraud agar with chloramphenicol and incubated at 25 °C for 5 days. The yeasts isolated were phenotypically identified by biochemical and micromorphological tests. Overall, 141 strains were isolated, of which 112 were from T. inunguis (Candida albicans, Candida parapsilosis sensu stricto, Candida orthopsilosis, Candida metapsilosis, Candida guilliermondii, Candida pelliculosa, Candida tropicalis, Candida glabrata, Candida famata, Candida krusei, Candida norvegensis, Candida ciferri, Trichosporon sp., Rhodotorula sp., Cryptococcus laurentii) and 29 were from T. manatus (C. albicans, C. tropicalis, C. famata, C. guilliermondii, C. krusei, Rhodotorula sp., Rhodotorula mucilaginosa, Rhodotorula minuta, Trichosporon sp.). This was the first systematic study to investigate the importance of yeasts as components of the microbiota of sirenians, demonstrating the presence of potentially pathogenic species, which highlights the importance of maintaining adequate artificial conditions for the health of captive manatees.

Candida potacharoeniae sp. nov. and Candida spenceri sp. nov., two novel galactose-containing ascomycetous anamorphic yeast species isolated in Thailand.

PubMed

Nakase, Takashi; Jindamorakot, Sasitorn; Imanishi, Yumi; Am-In, Somjit; Ninomiya, Shinya; Kawasaki, Hiroko; Limtong, Savitree

2010-08-01

Fifteen strains of anamorphic yeasts isolated from various natural substrates collected in various places in Thailand were found to represent two novel species of anamorphic yeast genus Candida based on the sequence analysis of the D1/D2 domain of the large subunit rRNA genes, chemotaxonomic and conventional properties used for the classification of yeasts. These strains are located in the clade including Candida etchellsii and Candida magnoliae. Fourteen strains represented by ST-490(T) (BCC 15176(T)=NBRC 106439(T)= CBS 11674(T)) are closely related to Candida sorbosivorans in the D1/D2 sequences but 11 nucleotides (2.4%) were substituted. The remaining strain, ST-594(T) (=BCC 15278(T)=NBRC 106446(T)=CBS 11673(T)) showed a close relationship to Candida geochares but 21 nucleotides (4.7%) were substituted. Apparently, these strains represent two novel Candida species of the Starmerella clade. The two species are described as Candida potacharoeniae sp. nov. and Candida spenceri sp. nov. in the present paper. Like the most species of this clade, the two species contain galactose in the cells in addition to glucose and mannose and have high mol% G + C of 54.4-55.9 and 54.9, respectively.

[Comparison of microdilution and disk diffusion methods for the detection of fluconazole and voriconazole susceptibility against clinical Candida glabrata isolates and determination of changing susceptibility with new CLSI breakpoints].

PubMed

Hazırolan, Gülşen; Sarıbaş, Zeynep; Arıkan Akdağlı, Sevtap

2016-07-01

Candida albicans is the most frequently isolated species as the causative agent of Candida infections. However, in recent years, the isolation rate of non-albicans Candida species have increased. In many centers, Candida glabrata is one of the commonly isolated non-albicans species of C.glabrata infections which are difficult-to-treat due to decreased susceptibility to fluconazole and cross-resistance to other azoles. The aims of this study were to determine the in vitro susceptibility profiles of clinical C.glabrata isolates against fluconazole and voriconazole by microdilution and disk diffusion methods and to evaluate the results with both the previous (CLSI) and current species-specific CLSI (Clinical and Laboratory Standards Institute) clinical breakpoints. A total of 70 C.glabrata strains isolated from clinical samples were included in the study. The identification of the isolates was performed by morphologic examination on cornmeal Tween 80 agar and assimilation profiles obtained by using ID32C (BioMérieux, France). Broth microdilution and disk diffusion methods were performed according to CLSI M27-A3 and CLSI M44-A2 documents, respectively. The results were evaluated according to CLSI M27-A3 and M44-A2 documents and new vs. species-specific CLSI breakpoints. By using both previous and new CLSI breakpoints, broth microdilution test results showed that voriconazole has greater in vitro activity than fluconazole against C.glabrata isolates. For the two drugs tested, very major error was not observed with disk diffusion method when microdilution method was considered as the reference method. Since "susceptible" category no more exists for fluconazole vs. C.glabrata, the isolates that were interpreted as susceptible by previous breakpoints were evaluated as susceptible-dose dependent by current CLSI breakpoints. Since species-specific breakpoints remain yet undetermined for voriconazole, comparative analysis was not possible for this agent. The results obtained

Comparison of the Vitek 2 yeast susceptibility system with CLSI microdilution for antifungal susceptibility testing of fluconazole and voriconazole against Candida spp., using new clinical breakpoints and epidemiological cutoff values.

PubMed

Pfaller, Michael A; Diekema, Daniel J; Procop, Gary W; Rinaldi, Michael G

2013-09-01

A commercially available, fully automated yeast susceptibility test system (Vitek 2; bioMérieux, Marcy d'Etoile, France) was compared in 3 different laboratories with the Clinical and Laboratory Standards Institute (CLSI) reference microdilution (BMD) method by testing 2 quality control strains, 10 reproducibility strains, and 425 isolates of Candida spp. against fluconazole and voriconazole. Reference CLSI BMD MIC endpoints and Vitek 2 MIC endpoints were read after 24 hours and 9.1-27.1 hours incubation, respectively. Excellent essential agreement (within 2 dilutions) between the reference and Vitek 2 MICs was observed for fluconazole (97.9%) and voriconazole (96.7%). Categorical agreement (CA) between the 2 methods was assessed using the new species-specific clinical breakpoints (CBPs): susceptible (S) ≤2 μg/mL, susceptible dose-dependent (SDD) 4 μg/mL, and resistant (R) ≥8 μg/mL for fluconazole and Candida albicans, Candida tropicalis, and Candida parapsilosis and ≤32 μg/mL (SDD), ≥64 μg/mL (R) for Candida glabrata; S ≤0.12 μg/mL, SDD 0.25-0.5 μg/mL, R ≥1 μg/mL for voriconazole and C. albicans, C. tropicalis, and C. parapsilosis, and ≤0.5 μg/mL (S), 1 μg/mL (SDD), ≥2 μg/mL (R) for Candida krusei. The epidemiological cutoff value (ECV) of 0.5 μg/mL for voriconazole and C. glabrata was used to differentiate wild-type (WT; MIC ≤ ECV) from non-WT (MIC > ECV) strains of this species. Due to the lack of CBPs for the less common species, the ECVs for fluconazole and voriconazole, respectively, were used for Candida lusitaniae (2 μg/mL and 0.03 μg/mL), Candida dubliniensis (0.5 μg/mL and 0.03 μg/mL), Candida guilliermondii (8 μg/mL and 0.25 μg/mL), and Candida pelliculosa (4 μg/mL and 0.25 μg/mL) to categorize isolates of these species as WT and non-WT. CA between the 2 methods was 96.8% for fluconazole and 96.5% for voriconazole with less than 1% very major errors and 1.3-3.0% major errors. The Vitek 2 yeast susceptibility system

Comparison of the MUREX C. albicans, Albicans-Sure, and BactiCard Candida test kits with the germ tube test for presumptive identification of Candida albicans.

PubMed Central

Crist, A E; Dietz, T J; Kampschroer, K

1996-01-01

The MUREX C. albicans (MC)(Murex Diagnostics), Albicans-Sure (AS) (Clinical Standards Laboratories), and BactiCard Candida (BC) (Remel) test kits were compared with the germ tube (GT) test for the rapid, presumptive identification of Candida albicans. All three test kits detect the enzymes L-proline aminopeptidase and beta-galactosaminidase in yeast cells grown on culture media and are based on the principle that C. albicans produces both enzymes whereas other yeasts produce only one or neither of the enzymes. The organisms evaluated were fresh clinical isolates identified by methods routinely used in our laboratory (API 20C system and conventional methods) and included 303 C. albicans isolates, 153 Candida glabrata isolates, 70 Candida tropicalis isolates, 36 Candida parapsilosis isolates, 13 isolates of other Candida spp., 5 Cryptococcus neoformans isolates, and 3 Saccharomyces cerevisiae isolates. The MC, AS, BC, and GT tests detected 299 (98.7%), 300 (99.0%), 301 (99.3%), and 287 (94.7%) C. albicans isolates, respectively. There was one false-positive result with both the MC and BC kits and two false-positive results with the GT test. The enzymatic methods evaluated in this study provide rapid and accurate alternatives to the GT test for the presumptive identification of C. albicans. PMID:8880535

Candida asparagi sp. nov., Candida diospyri sp. nov. and Candida qinlingensis sp. nov., novel anamorphic, ascomycetous yeast species.

PubMed

Lu, Hui-Zhong; Jia, Jian-Hua; Wang, Qi-Ming; Bai, Feng-Yan

2004-07-01

Among ascomycetous yeasts that were isolated from several nature reserve areas in China, three anamorphic strains isolated from soil (QL 5-5T) and fruit (QL 21-2T and SN 15-1T) were revealed, by conventional characterization and molecular phylogenetic analysis based on internal transcribed spacer and large subunit (26S) rRNA gene D1/D2 region sequencing, to represent three novel species in the genus Candida. Candida qinlingensis sp. nov. (type strain, QL 5-5T=AS 2.2524T=CBS 9768T) was related closely to a teleomorphic species, Williopsis pratensis. The close relatives of Candida diospyri sp. nov. (type strain, QL 21-2T=AS 2.2525T=CBS 9769T) are Candida friedrichii and Candida membranifaciens. Candida asparagi sp. nov. (type strain, SN 15-1T=AS 2.2526T=CBS 9770T) forms a clade with Candida fructus.

The CgHaa1-Regulon Mediates Response and Tolerance to Acetic Acid Stress in the Human Pathogen Candida glabrata

PubMed Central

Bernardo, Ruben T.; Cunha, Diana V.; Wang, Can; Pereira, Leonel; Silva, Sónia; Salazar, Sara B.; Schröder, Markus S.; Okamoto, Michiyo; Takahashi-Nakaguchi, Azusa; Chibana, Hiroji; Aoyama, Toshihiro; Sá-Correia, Isabel; Azeredo, Joana; Butler, Geraldine; Mira, Nuno Pereira

2016-01-01

To thrive in the acidic vaginal tract, Candida glabrata has to cope with high concentrations of acetic acid. The mechanisms underlying C. glabrata tolerance to acetic acid at low pH remain largely uncharacterized. In this work, the essential role of the CgHaa1 transcription factor (encoded by ORF CAGL0L09339g) in the response and tolerance of C. glabrata to acetic acid is demonstrated. Transcriptomic analysis showed that CgHaa1 regulates, directly or indirectly, the expression of about 75% of the genes activated under acetic acid stress. CgHaa1-activated targets are involved in multiple physiological functions including membrane transport, metabolism of carbohydrates and amino acids, regulation of the activity of the plasma membrane H+-ATPase, and adhesion. Under acetic acid stress, CgHaa1 increased the activity and the expression of the CgPma1 proton pump and contributed to increased colonization of vaginal epithelial cells by C. glabrata. CgHAA1, and two identified CgHaa1-activated targets, CgTPO3 and CgHSP30, are herein demonstrated to be determinants of C. glabrata tolerance to acetic acid. The protective effect of CgTpo3 and of CgHaa1 was linked to a role of these proteins in reducing the accumulation of acetic acid inside C. glabrata cells. In response to acetic acid stress, marked differences were found in the regulons controlled by CgHaa1 and by its S. cerevisiae ScHaa1 ortholog, demonstrating a clear divergent evolution of the two regulatory networks. The results gathered in this study significantly advance the understanding of the molecular mechanisms underlying the success of C. glabrata as a vaginal colonizer. PMID:27815348

Use of CHROMagar Candida for genital specimens in the diagnostic laboratory.

PubMed Central

Houang, E T; Chu, K C; Koehler, A P; Cheng, A F

1997-01-01

OBJECTIVE: To evaluate CHROMagar Candida (CA), a new yeast differential medium, for yeast isolation in a clinical laboratory for the routine examination of high vaginal swabs. METHODS: Results of high vaginal swab cultures processed in a standard manner on plates containing equal halves of Sabouraud dextrose agar (SDA) and CA were compared. Non-Candida albicans yeast isolates were further speciated with API 20C AUX or API 32C. To assess the ease of use of CA, laboratory staff lacking in experience of the medium were asked to identify 23 unlabelled yeast cultures on CA by referring to six labelled reference plates. RESULTS: Of the 1784 swab cultures processed, yeasts were isolated from 373 SDA and 368 CA. Of the 78 non-albicans isolates further speciated, CA identified correctly all cultures of C krusei and C tropicalis, and 82% of C glabrata. All the 38 inexperienced laboratory staff achieved 100% accuracy for C albicans and over 90% for C krusei and C tropicalis. CONCLUSIONS: CA is a satisfactory isolation medium for genital specimens, allowing immediate and correct identification of the commonly encountered yeasts and easy recognition of mixed cultures. Images PMID:9306935

In vitro investigation of antifungal activity of allicin alone and in combination with azoles against Candida species.

PubMed

Khodavandi, Alireza; Alizadeh, Fahimeh; Aala, Farzad; Sekawi, Zamberi; Chong, Pei Pei

2010-04-01

Candidiasis is a term describing infections by yeasts from the genus Candida, and the type of infection encompassed by candidiasis ranges from superficial to systemic. Treatment of such infections often requires antifungals such as the azoles, but increased use of these drugs has led to selection of yeasts with increased resistance to these drugs. In this study, we used allicin, an allyl sulfur derivative of garlic, to demonstrate both its intrinsic antifungal activity and its synergy with the azoles, in the treatment of these yeasts in vitro. In this study, the MIC(50) and MIC(90) of allicin alone against six Candida spp. ranged from 0.05 to 25 microg/ml. However, when allicin was used in combination with fluconazole or ketoconazole, the MICs were decreased in some isolates. Our results demonstrated the existing synergistic effect between allicin and azoles in some of the Candida spp. such as C. albicans, C. glabrata and C. tropicalis, but synergy was not demonstrated in the majority of Candida spp. tested. Nonetheless, In vivo testing needs to be performed to support these findings.

Combinatorial stresses kill pathogenic Candida species

PubMed Central

Kaloriti, Despoina; Tillmann, Anna; Cook, Emily; Jacobsen, Mette; You, Tao; Lenardon, Megan; Ames, Lauren; Barahona, Mauricio; Chandrasekaran, Komelapriya; Coghill, George; Goodman, Daniel; Gow, Neil A. R.; Grebogi, Celso; Ho, Hsueh-Lui; Ingram, Piers; McDonagh, Andrew; De Moura, Alessandro P. S.; Pang, Wei; Puttnam, Melanie; Radmaneshfar, Elahe; Romano, Maria Carmen; Silk, Daniel; Stark, Jaroslav; Stumpf, Michael; Thiel, Marco; Thorne, Thomas; Usher, Jane; Yin, Zhikang; Haynes, Ken; Brown, Alistair J. P.

2012-01-01

Pathogenic microbes exist in dynamic niches and have evolved robust adaptive responses to promote survival in their hosts. The major fungal pathogens of humans, Candida albicans and Candida glabrata, are exposed to a range of environmental stresses in their hosts including osmotic, oxidative and nitrosative stresses. Significant efforts have been devoted to the characterization of the adaptive responses to each of these stresses. In the wild, cells are frequently exposed simultaneously to combinations of these stresses and yet the effects of such combinatorial stresses have not been explored. We have developed a common experimental platform to facilitate the comparison of combinatorial stress responses in C. glabrata and C. albicans. This platform is based on the growth of cells in buffered rich medium at 30°C, and was used to define relatively low, medium and high doses of osmotic (NaCl), oxidative (H 2O2) and nitrosative stresses (e.g., dipropylenetriamine (DPTA)-NONOate). The effects of combinatorial stresses were compared with the corresponding individual stresses under these growth conditions. We show for the first time that certain combinations of combinatorial stress are especially potent in terms of their ability to kill C. albicans and C. glabrata and/or inhibit their growth. This was the case for combinations of osmotic plus oxidative stress and for oxidative plus nitrosative stress. We predict that combinatorial stresses may be highly signif cant in host defences against these pathogenic yeasts. PMID:22463109

Evaluation of risk factors in patients with vulvovaginal candidiasis and the value of chromID Candida agar versus CHROMagar Candida for recovery and presumptive identification of vaginal yeast species.

PubMed

Guzel, Ahmet Bariş; Ilkit, Macit; Akar, Tuba; Burgut, Refik; Demir, S Cansun

2011-01-01

Vulvovaginal candidiasis (VVC), particularly the recurrent form, remains an intractable problem for clinicians, microbiologists, and patients. It is essential to confirm the clinical diagnosis by mycological methods and avoid empirical therapy. The recovery of yeast in fungal culture, such as on Sabouraud dextrose agar, remains the gold standard for diagnosis. In this investigation, we examined 474 participants, including 122 (25.7%) with acute VVC cases, 249 (52.5%) who had recurrent VVC (RVVC) cases, and 103 (21.7%) healthy controls. We also administered a questionnaire to obtain information on patient lifestyle and medical, gynecological, and sexual history. In addition, we compared the performance of chromID Candida agar (CAN2) to CHROMagar Candida (CAC) and Sabouraud dextrose agar with gentamicin and chloramphenicol (SGC2). The yeasts were identified by conventional methods including the germ tube test, microscopic morphology on cornmeal-Tween 80 agar, and the commercial API 20C AUX system. We detected yeasts in 60 of 122 (49.2%) patients with acute VVC cases, 110 of 249 (44.2%) with RVVC cases, and in 35 of 103 (34%) healthy controls (P = 0.07). A total of 205 samples were found to be positive for fungi (43.2%), of which 176 (85.9%) were monofungal, and 29 (14.1%) were polyfungal. In addition, 198 of these samples (96.6%) were positive on CAN2, 195 (95.1%) on CAC, 189 (92.2%) on SGC2, and 183 (89.3%) samples on all three (P = 0.17). The 234 yeast isolates recovered were C. albicans (n = 118), C. glabrata (n = 82), C. kefyr (n = 11), C. krusei (n = 9), C. lipolytica (n = 3), C. colliculosa (n = 2), C. parapsilosis (n = 2), C. pelliculosa (n = 2), C. tropicalis (n = 2), and other species of Candida (n = 3). Of the 29 polyfungal populations, 28 (96.6%) were detected in CAN2, 25 in (86.2%) CAC, and 25 (86.2%) on both (P = 0.35). Notably, we detected the high predominance of C. albicans+C. glabrata (86.2%) in polyfungal populations. Briefly, the detection of C

Comparative evaluation of six chromogenic media for presumptive yeast identification.

PubMed

Vecchione, Alessandra; Florio, Walter; Celandroni, Francesco; Barnini, Simona; Lupetti, Antonella; Ghelardi, Emilia

2017-12-01

The present study was undertaken to evaluate the discrimination ability of six chromogenic media in presumptive yeast identification. We analysed 108 clinical isolates and reference strains belonging to eight different species: Candida albicans , Candida dubliniensis , Candida tropicalis , Candida krusei , Candida glabrata , Candida parapsilosis , Candida lusitaniae and Trichosporon mucoides . C. albicans , C. tropicalis and C. krusei could be distinguished from one another in all the tested chromogenic media, as predicted by the manufacturers. In addition, C. albicans could be distinguished from C. dubliniensis on BBL CHROMagar Candida, Kima CHROMagar Candida and Brilliance Candida, and C. parapsilosis could be identified on CHROMATIC Candida agar, CHROMOGENIC Candida agar, and Brilliance Candida agar. Brilliance Candida provided the widest discrimination ability, being able to discriminate five out of the seven Candida species tested. Interestingly, C. tropicalis and C. krusei could be already distinguished from each other after 24 hours of incubation. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

[Comparison of Phoenix™ Yeast ID Panel and API® ID 32C commercial systems for the identification of Candida species isolated from clinical samples].

PubMed

Gayibova, Ülkü; Dalyan Cılo, Burcu; Ağca, Harun; Ener, Beyza

2014-07-01

Opportunistic fungal pathogens are one of the important causes of nosocomial infections, and several different types of yeasts, especially Candida species are increasingly recovered from immunocompromised patients. Since many of the yeasts are resistant to the commonly used antifungal agents, the introduction of appropriate therapy depends on rapid and accurate identification. The aims of this study were to compare the commercial identification systems namely API® ID 32C (bioMerieux, France) and Phoenix™ Yeast ID Panel (Becton Dickinson Diagnostics, USA) for the identification of Candida species and to evaluate the effect of morphological findings in the identification process. A total of 211 yeast strains isolated from different clinical samples (111 urine, 34 blood/vascular catheter, 27 upper/lower respiratory tract, 16 abscess/pus, 13 throat/vagina swabs and 10 sterile body fluids) of 137 patients hospitalized in Uludag University Health and Research Center between October 2013 to January 2014, were included in the study. Samples were cultured on blood agar, chromogenic agar (CHROMagar Candida, BD, USA) and Saboraud's dextrose agar (SDA), and isolated yeast colonies were evaluated with germ tube test and morphological examination by microscopy on cornmeal/Tween-80 agar. The isolates were identified as well by two commercial systems according to the manufacturers' recommendations. Discrepant results between the systems were tried to be resolved by using morphological characteristics of the yeasts. Of the isolates 159 were identified identical by both of the systems, and the concordance between those systems were estimated as 75.4%. According to the concordant identification, the most frequently isolated species was C.albicans (44.1%) followed by C.tropicalis (9.9%), C.glabrata (9.5%), C.parapsilosis (8.5%) and C.kefyr (8.1%). The concordance rate was 81.7% in identification of frequently isolated species (C.albicans, C.tropicalis, C.parapsilosis, C.glabrata, C

Heteroresistance to Fluconazole Is a Continuously Distributed Phenotype among Candida glabrata Clinical Strains Associated with In Vivo Persistence.

PubMed

Ben-Ami, Ronen; Zimmerman, Offer; Finn, Talya; Amit, Sharon; Novikov, Anna; Wertheimer, Noa; Lurie-Weinberger, Mor; Berman, Judith

2016-08-02

Candida glabrata causes persistent infections in patients treated with fluconazole and often acquires resistance following exposure to the drug. Here we found that clinical strains of C. glabrata exhibit cell-to-cell variation in drug response (heteroresistance). We used population analysis profiling (PAP) to assess fluconazole heteroresistance (FLC(HR)) and to ask if it is a binary trait or a continuous phenotype. Thirty (57.6%) of 52 fluconazole-sensitive clinical C. glabrata isolates met accepted dichotomous criteria for FLC(HR) However, quantitative grading of FLC(HR) by using the area under the PAP curve (AUC) revealed a continuous distribution across a wide range of values, suggesting that all isolates exhibit some degree of heteroresistance. The AUC correlated with rhodamine 6G efflux and was associated with upregulation of the CDR1 and PDH1 genes, encoding ATP-binding cassette (ABC) transmembrane transporters, implying that HetR populations exhibit higher levels of drug efflux. Highly FLC(HR) C. glabrata was recovered more frequently than nonheteroresistant C. glabrata from hematogenously infected immunocompetent mice following treatment with high-dose fluconazole (45.8% versus 15%, P = 0.029). Phylogenetic analysis revealed some phenotypic clustering but also variations in FLC(HR) within clonal groups, suggesting both genetic and epigenetic determinants of heteroresistance. Collectively, these results establish heteroresistance to fluconazole as a graded phenotype associated with ABC transporter upregulation and fluconazole efflux. Heteroresistance may explain the propensity of C. glabrata for persistent infection and the emergence of breakthrough resistance to fluconazole. Heteroresistance refers to variability in the response to a drug within a clonal cell population. This phenomenon may have crucial importance for the way we look at antimicrobial resistance, as heteroresistant strains are not detected by standard laboratory susceptibility testing

Non-albicans Candida Vulvovaginitis: Treatment Experience at a Tertiary Care Vaginitis Center.

PubMed

Powell, Anna M; Gracely, Edward; Nyirjesy, Paul

2016-01-01

The aims of this study are to analyze a cohort of women with vulvovaginal symptoms and positive cultures for non-albicans Candida (NAC) to determine whether yeast was responsible for their symptoms and to evaluate the mycological effectiveness of various regimens. This observational study was performed from retrospective chart review of patients with positive NAC cultures between April 1, 2008, and January 31, 2011, at a tertiary care vaginitis center. Patient intake demographics were entered into a database. Follow-up visits were analyzed for data about patient treatments and outcomes. Patients were considered a clinical cure if their symptoms were significantly improved and mycologic cure (MC) if later yeast cultures were negative. If clinical symptoms improved at the same time as MC, the isolate was considered the proximate cause for the symptoms. One hundred eight patients meeting entry criteria were analyzed. Boric acid was effective at obtaining MC in 32 (78%) of 41 patients with C. glabrata, 3 of 3 patients with C. tropicalis, and 3 of 3 patients with C. lusitaniae. Fluconazole was effective as initial treatment for 3 (60%) of 5 patients with C. glabrata and 13 (81%) of 16 patients with C. parapsilosis. In 52.7% of C. glabrata, 66.7% of C. parapsilosis, and 57.1% of C. tropicalis cases, effective antifungal therapy led to symptom improvement. In a tertiary care vaginitis center, NAC, when isolated on culture, caused clinically significant infections in approximately half of symptomatic patients. A majority of infections can be effectively treated with boric acid or fluconazole regardless of the non-albicans Candida species.

Fungal CYP51 Inhibitors VT-1161 and VT-1129 Exhibit Strong In Vitro Activity against Candida glabrata and C. krusei Isolates Clinically Resistant to Azole and Echinocandin Antifungal Compounds.

PubMed

Schell, W A; Jones, A M; Garvey, E P; Hoekstra, W J; Schotzinger, R J; Alexander, B D

2017-03-01

The in vitro activities of fungal CYP51 inhibitors VT-1161 and VT-1129 were determined for Candida glabrata ( n = 34) and C. krusei ( n = 50). C. glabrata isolates were screened for FKS gene mutations. All isolates were resistant clinically and/or in vitro to at least one standard antifungal compound. VT-1161 and VT-1129 MICs for all isolates were at least 5-fold below achievable human plasma levels for VT-1161. VT-1161 and VT-1129 are promising for the treatment of resistant C. glabrata and C. krusei infections. Copyright © 2017 American Society for Microbiology.

Identification of a polysaccharide produced by the pyruvate overproducer Candida glabrata CCTCC M202019.

PubMed

Luo, Zhengshan; Liu, Song; Du, Guocheng; Zhou, Jingwen; Chen, Jian

2017-06-01

Candida glabrata has great potential for the accumulation of pyruvate as a preferred strain in pyruvate production by fermentation. However, its substrate conversion rate is relatively low. In this study, a novel polysaccharide containing α-1,4-glucosidic bonds was observed accidentally in screening a high-titer pyruvate strain by atmospheric and room temperature plasma mutagenesis of C. glabrata. Chemical analysis of the partially purified polysaccharide S 4-C10 showed the main components were 1.2% (w/w) protein and 94.2% (w/w) total sugar. Fourier transform infrared and molecular mass distribution analysis indicated that the main component (PSG-2) of S 4-C10 was a small molecular homogeneous protein-bound polysaccharide. Monosaccharide analysis of PSG-2 showed it consisted of glucose, mannose, and fructose. By optimizing the vitamin mix content, 77.6 g L -1 S 4-C10 polysaccharide could be obtained after 72 h fermentation at 30 °C in 500-mL flasks. RT-qPCR analysis showed that transcriptional level of some key genes related to polysaccharide biosynthesis was upregulated compared to that of wild-type strain. By knocking out two most significantly upregulated genes, CAGL0H02695g and CAGL0K10626g, in the wild-type strain, the pyruvate consumption rate was significantly reduced in late pyruvate fermentation phase, while the titer of polysaccharides was reduced by 18.0%. Besides the potential applications of the novel identified polysaccharide, this study provided clues for increasing the conversion ratio of glucose to pyruvate in C. glabrata by further decreasing the accumulation of polysaccharides.

Fluconazole Resistance Associated with Drug Efflux and Increased Transcription of a Drug Transporter Gene, PDH1, in Candida glabrata

PubMed Central

Miyazaki, Haruko; Miyazaki, Yoshitsugu; Geber, Antonia; Parkinson, Tanya; Hitchcock, Christopher; Falconer, Derek J.; Ward, Douglas J.; Marsden, Katherine; Bennett, John E.

1998-01-01

Sequential Candida glabrata isolates were obtained from the mouth of a patient infected with human immunodeficiency virus type 1 who was receiving high doses of fluconazole for oropharyngeal thrush. Fluconazole-susceptible colonies were replaced by resistant colonies that exhibited both increased fluconazole efflux and increased transcripts of a gene which codes for a protein with 72.5% identity to Pdr5p, an ABC multidrug transporter in Saccharomyces cerevisiae. The deduced protein had a molecular mass of 175 kDa and was composed of two homologous halves, each with six putative transmembrane domains and highly conserved sequences of ATP-binding domains. When the earliest and most azole-susceptible isolate of C. glabrata from this patient was exposed to fluconazole, increased transcripts of the PDR5 homolog appeared, linking azole exposure to regulation of this gene. PMID:9661006

Endoscopic Endonasal Transsphenoidal Drainage of a Spontaneous Candida glabrata Pituitary Abscess.

PubMed

Strickland, Ben A; Pham, Martin; Bakhsheshian, Joshua; Carmichael, John; Weiss, Martin; Zada, Gabriel

2018-01-01

Noniatrogenic pituitary abscess remains a rare clinical entity, and is the indication for surgery in <1% of transsphenoidal approaches. Correct diagnosis of this rare entity is often delayed. Without timely treatment, morbidity and mortality are high. Of the 200 cases reported to date, less than one-half have identified a causative organism. We report the second case of a pituitary abscess caused by Candida species, and also provide an intraoperative video showing the endoscopic management of this pathology. A 33-year-old woman presented with headache, hypopituitarism, and vision loss in the setting of diabetic ketoacidosis, and was found to have multiple abscesses in the liver, lung, kidney, and uterus. Brain magnetic resonance imaging revealed a 15-mm cystic sellar mass with restricted diffusion. The patient underwent urgent evacuation of the abscess via an endoscopic endonasal transsphenoidal route, with obvious purulent material filling the sella, later identified as Candida glabrata. Antimicrobial therapy was refined appropriately, and she exhibited significant improvement in neurologic function, although endocrinopathy has persisted. With timely management, including a combination of surgical drainage and appropriate antimicrobial therapy, neurologic outcomes are good in most cases of pituitary abscess; however, endocrinopathy often does not improve. Although most reported cases with identified causative organisms speciate bacteria, some cases are of fungal etiology and require different antimicrobial agents. This further underscores the importance of identifying the causative agent. Copyright © 2017 Elsevier Inc. All rights reserved.

Epidemiology of echinocandin resistance in Candida

PubMed Central

Grossman, Nina T.; Chiller, Tom M.; Lockhart, Shawn R.

2018-01-01

Echinocandins are the newest antifungal agents approved for use in treating Candida infections in the US. They act by interfering with 1,3-β-D-glucan synthase and therefore disrupt cell wall production and lead to Candida cell death. There is no intrinsic resistance to echinocandins among Candida species, and isolates from historic collections archived before the release of the echinocandins show no resistance. Resistance to the echinocandins remains low among most Candida species and ranges overall from 0–1%. Among isolates of Candida glabrata, the proportion of resistant isolates is higher and has been reported to be as high as 13.5% in at least one hospital. Antifungal resistance is due to specific amino acid mutations in the Fksp subunit(s) of the 1,3-β-D-glucan synthase protein which are localized to one of two hotspots. These mutations are being recognized in isolates from patients who have failed echinocandin therapy, and often lead to a poor outcome. While the future looks bright for the echinocandins against most Candida species, C. glabrata remains a species of concern and resistance rates of C. glabrata to the echinocandins should be monitored closely. PMID:29780439

Epidemiology of echinocandin resistance in Candida.

PubMed

Grossman, Nina T; Chiller, Tom M; Lockhart, Shawn R

2014-12-01

Echinocandins are the newest antifungal agents approved for use in treating Candida infections in the US. They act by interfering with 1,3-β-D-glucan synthase and therefore disrupt cell wall production and lead to Candida cell death. There is no intrinsic resistance to echinocandins among Candida species, and isolates from historic collections archived before the release of the echinocandins show no resistance. Resistance to the echinocandins remains low among most Candida species and ranges overall from 0-1%. Among isolates of Candida glabrata , the proportion of resistant isolates is higher and has been reported to be as high as 13.5% in at least one hospital. Antifungal resistance is due to specific amino acid mutations in the Fksp subunit(s) of the 1,3-β-D-glucan synthase protein which are localized to one of two hotspots. These mutations are being recognized in isolates from patients who have failed echinocandin therapy, and often lead to a poor outcome. While the future looks bright for the echinocandins against most Candida species, C. glabrata remains a species of concern and resistance rates of C. glabrata to the echinocandins should be monitored closely.

A Novel Flucytosine-Resistant Yeast Species, Candida pseudoaaseri, Causes Disease in a Cancer Patient ▿

PubMed Central

Pfüller, Roland; Gräser, Yvonne; Erhard, Marcel; Groenewald, Marizeth

2011-01-01

Some members of the genus Candida are among the most common human fungal pathogens and cause serious diseases especially in immunocompromised people. A yeast was isolated from a blood culture from an immunocompromised cancer patient who suffered from acute pneumonia. The growth characteristics of the yeast on CHROMagar Candida were similar to those of Candida tropicalis, whereas the API ID 32C system identified the yeast as Candida silvicola. On the basis of the nucleotide divergence in the D1/D2 domain of the 26S nuclear rRNA (nrRNA) gene, as well as the internal transcribed spacer (ITS) domain of the nrRNA gene region, a new species, Candida pseudoaaseri sp. nov. with type strain VK065094 (CBS 11170T), which was found to be closely related to Candida aaseri, is proposed. While C. aaseri strains were susceptible to all tested antifungals, the new species is resistant to flucytosine and may also be distinguished from C. aaseri by its ability to assimilate l-rhamnose, whereas its colony morphology on CHROMagar Candida may be helpful for differentiation. PMID:21976765

Epidemiology and antifungal susceptibilities of yeasts causing vulvovaginitis in a teaching hospital.

PubMed

Gamarra, Soledad; Morano, Susana; Dudiuk, Catiana; Mancilla, Estefanía; Nardin, María Elena; de Los Angeles Méndez, Emilce; Garcia-Effron, Guillermo

2014-10-01

Vulvovaginal candidiasis is one of the most common mycosis. However, the information about antifungal susceptibilities of the yeasts causing this infection is scant. We studied 121 yeasts isolated from 118 patients with vulvovaginal candidiasis. The isolates were identified by phenotypic and molecular methods, including four phenotypic methods described to differentiate Candida albicans from C. dubliniensis. Antifungal susceptibility testing was performed according to CLSI documents M27A3 and M27S4 using the drugs available as treatment option in the hospital. Diabetes, any antibacterial and amoxicillin treatment were statistically linked with vulvovaginal candidiasis, while oral contraceptives were not considered a risk factor. Previous azole-based over-the-counter antifungal treatment was statistically associated with non-C.albicans yeasts infections. The most common isolated yeast species was C. albicans (85.2 %) followed by C. glabrata (5 %), Saccharomyces cerevisiae (3.3 %), and C. dubliniensis (2.5 %). Fluconazole- and itraconazole-reduced susceptibility was observed in ten and in only one C. albicans strains, respectively. All the C. glabrata isolates showed low fluconazole MICs. Clotrimazole showed excellent potency against all but seven isolates (three C. glabrata, two S. cerevisiae, one C. albicans and one Picchia anomala). Any of the strains showed nystatin reduced susceptibility. On the other hand, terbinafine was the less potent drug. Antifungal resistance is still a rare phenomenon supporting the use of azole antifungals as empirical treatment of vulvovaginal candidiasis.

Candida alocasiicola sp. nov., Candida hainanensis sp. nov., Candida heveicola sp. nov. and Candida musiphila sp. nov., novel anamorphic, ascomycetous yeast species isolated from plants.

PubMed

Wang, Shi-An; Jia, Jian-Hua; Bai, Feng-Yan

2008-08-01

In a taxonomic study on the ascomycetous yeasts isolated from plant materials collected in tropical forests in Yunnan and Hainan Provinces, southern China, four strains isolated from tree sap (YJ2E(T)) and flowers (YF9E(T), YWZH3C(T) and YYF2A(T)) were revealed to represent four undescribed yeast species. Molecular phylogenetic analysis based on the large subunit (26S) rRNA gene D1/D2 domain sequences showed that strain YJ2E(T) was located in a clade together with Candida haemulonii and C. pseudohaemulonii. Strain YF9E(T) was most closely related to C. azyma and strain YWZH3C(T) to C. sorbophila and C. spandovensis. Strain YYF2A(T) was clustered in a clade containing small-spored Metschnikowia species and related anamorphic Candida species. The new strains differed from their closely related described species by more than 10% mismatches in the D1/D2 domain. No sexual states were observed for the four strains on various sporulation media. The new species are therefore assigned to the genus Candida and described as Candida alocasiicola sp. nov. (type strain, YF9E(T) = AS 2.3484(T) = CBS 10702(T)), Candida hainanensis sp. nov. (type strain, YYF2A(T) = AS 2.3478(T) = CBS 10696(T)), Candida heveicola sp. nov. (type strain, YJ2E(T) = AS 2.3483(T) = CBS 10701(T)) and Candida musiphila sp. nov. (type strain, YWZH3C(T) = AS 2.3479(T) = CBS 10697(T)).

Candida nivariensis as a New Emergent Agent of Vulvovaginal Candidiasis: Description of Cases and Review of Published Studies.

PubMed

Aznar-Marin, Pilar; Galan-Sanchez, Fátima; Marin-Casanova, Pilar; García-Martos, Pedro; Rodríguez-Iglesias, Manuel

2016-06-01

Candida nivariensis is a new emergent agent related to human infections in the vaginal tract and other localizations, but the phenotypic characteristics are very similar to Candida glabrata and can be misidentified and underdiagnosed. We described four cases of vulvovaginitis identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and confirmed the results with PCR amplification and sequencing of the entire ITS genomic region (ITS1, ITS2 and 5.8 rRNA). We reinforce the need for new diagnostic tools for the correct identification of yeast infections.

The secretory pathway: exploring yeast diversity.

PubMed

Delic, Marizela; Valli, Minoska; Graf, Alexandra B; Pfeffer, Martin; Mattanovich, Diethard; Gasser, Brigitte

2013-11-01

Protein secretion is an essential process for living organisms. In eukaryotes, this encompasses numerous steps mediated by several hundred cellular proteins. The core functions of translocation through the endoplasmic reticulum membrane, primary glycosylation, folding and quality control, and vesicle-mediated secretion are similar from yeasts to higher eukaryotes. However, recent research has revealed significant functional differences between yeasts and mammalian cells, and even among diverse yeast species. This review provides a current overview of the canonical protein secretion pathway in the model yeast Saccharomyces cerevisiae, highlighting differences to mammalian cells as well as currently unresolved questions, and provides a genomic comparison of the S. cerevisiae pathway to seven other yeast species where secretion has been investigated due to their attraction as protein production platforms, or for their relevance as pathogens. The analysis of Candida albicans, Candida glabrata, Kluyveromyces lactis, Pichia pastoris, Hansenula polymorpha, Yarrowia lipolytica, and Schizosaccharomyces pombe reveals that many - but not all - secretion steps are more redundant in S. cerevisiae due to duplicated genes, while some processes are even absent in this model yeast. Recent research obviates that even where homologous genes are present, small differences in protein sequence and/or differences in the regulation of gene expression may lead to quite different protein secretion phenotypes. © 2013 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

Identification of Candida lusitaniae as an opportunistic yeast in humans.

PubMed

Holzschu, D L; Presley, H L; Miranda, M; Phaff, H J

1979-08-01

Four yeast strains, causally associated with infection in a patient with acute myelogenous leukemia, were identified by standard methods currently used in yeast taxonomy as representatives of Candida lusitania van Uden et do Carmo-Sousa. Because this species has not been recognized previously as an opportunistic yeast in humans, molecular taxonomic methods were applied to confirm its identity. The nuclear deoxyribonucleic acid (DNA) base composition of two clinical isolates was shown to be 45.1 mol% guanine plus cytosine as compared to 44.7 mol% guanine plus cytosine for the type strain of this species. DNA/DNA reassociation experiments revealed more than 95% complementarity between the DNAs from the clinical isolates and that of the type strain of C. lusitaniae, thus confirming their classification by conventional taxonomy. A key is provided to differentiate C. lusitaniae from two phenotypically similar Candida species.

Identification of Candida lusitaniae as an opportunistic yeast in humans.

PubMed Central

Holzschu, D L; Presley, H L; Miranda, M; Phaff, H J

1979-01-01

Four yeast strains, causally associated with infection in a patient with acute myelogenous leukemia, were identified by standard methods currently used in yeast taxonomy as representatives of Candida lusitania van Uden et do Carmo-Sousa. Because this species has not been recognized previously as an opportunistic yeast in humans, molecular taxonomic methods were applied to confirm its identity. The nuclear deoxyribonucleic acid (DNA) base composition of two clinical isolates was shown to be 45.1 mol% guanine plus cytosine as compared to 44.7 mol% guanine plus cytosine for the type strain of this species. DNA/DNA reassociation experiments revealed more than 95% complementarity between the DNAs from the clinical isolates and that of the type strain of C. lusitaniae, thus confirming their classification by conventional taxonomy. A key is provided to differentiate C. lusitaniae from two phenotypically similar Candida species. PMID:292646

Mitochondrial Cochaperone Mge1 Is Involved in Regulating Susceptibility to Fluconazole in Saccharomyces cerevisiae and Candida Species.

PubMed

Demuyser, Liesbeth; Swinnen, Erwin; Fiori, Alessandro; Herrera-Malaver, Beatriz; Vestrepen, Kevin; Van Dijck, Patrick

2017-07-18

MGE1 encodes a yeast chaperone involved in Fe-S cluster metabolism and protein import into the mitochondria. In this study, we identified MGE1 as a multicopy suppressor of susceptibility to the antifungal fluconazole in the model yeast Saccharomyces cerevisiae We demonstrate that this phenomenon is not exclusively dependent on the integrity of the mitochondrial DNA or on the presence of the drug efflux pump Pdr5. Instead, we show that the increased dosage of Mge1 plays a protective role by retaining increased amounts of ergosterol upon fluconazole treatment. Iron metabolism and, more particularly, Fe-S cluster formation are involved in regulating this process, since the responsible Hsp70 chaperone, Ssq1, is required. Additionally, we show the necessity but, by itself, insufficiency of activating the iron regulon in establishing the Mge1-related effect on drug susceptibility. Finally, we confirm a similar role for Mge1 in fluconazole susceptibility in the pathogenic fungi Candida glabrata and Candida albicans IMPORTANCE Although they are mostly neglected compared to bacterial infections, fungal infections pose a serious threat to the human population. While some of them remain relatively harmless, infections that reach the bloodstream often become lethal. Only a few therapies are available, and resistance of the pathogen to these drugs is a frequently encountered problem. It is thus essential that more research is performed on how these pathogens cope with the treatment and cause recurrent infections. Baker's yeast is often used as a model to study pathogenic fungi. We show here, by using this model, that iron metabolism and the formation of the important iron-sulfur clusters are involved in regulating susceptibility to fluconazole, the most commonly used antifungal drug. We show that the same process likely also occurs in two of the most regularly isolated pathogenic fungi, Candida glabrata and Candida albicans . Copyright © 2017 Demuyser et al.

Soaps and germicides as adjunct topical antimycotic agents on candida species implicated in vulvovaginal candidasis.

PubMed

Ogunshe, Adenike A O; Omotoso, Oluwatoyin A; Akindele, Titilayo M

2011-06-01

The study aims at evaluating the potentials of soaps and germicides/disinfectants as adjunct topical anti-vulvovaginal candidasis agents. In vitro inhibitory activities of the test agents, prepared according to the manufacturer's specification for toilet and midwifery purposes were determined using modified agar well-diffusion method. Varied susceptibility patterns were exhibited by Candida albicans (26.5%), C. glabrata (18.4%), C. pseudotropicalis (14.3%) and C. tropicalis (40.8%) implicated in vulvovaginal candidasis, indicating Crusader oil (100%), Meriko (95%), Tetmosol (84.7%) and Aloe (68.4%) as the most inhibitory soaps against the Candida strains. The in vitro inhibitory activities of the germicides and disinfectants ranged between (Dettol; 34.6% and Purit; 84.6%) for C. albicans; (Roberts; 33.3% and Purit; 83.3%) for C. glabrata; (Roberts; 21.4% and Purit; 92.9%) for C. pseudotropicalis; (Dettol; 35.0% and Purit; 87.5%) for C. tropicalis respectively. All the Candida strains were totally inhibited by the germicides and disinfectants at the second lower dilutions, except in Morigad towards C. albicans (69.2%]) C. glabrata (72.2%), C. pseudotropicalis (92.9%) and C. tropicalis (82.5%) but none of the vaginal Lactobacillus strains was inhibited by the soaps, germicides or disinfectant. About 90% of a control group indicated relief after pubic cleansing with soaps, germicides and disinfectants. Results indicatied the safety of soaps, germicides and disinfectants as potential adjunct topical cleansing-agents in cases of vaginal itching and candidasis, a common mucosal infection caused by opportunistic yeasts of the Candida genus.

Identification of Candida Species Using MP65 Gene and Evaluation of the Candida albicans MP65 Gene Expression in BALB/C Mice.

PubMed

Bineshian, Farahnaz; Yadegari, Mohammad Hossien; Sharifi, Zohre; Akbari Eidgahi, Mohammadreza; Nasr, Reza

2015-05-01

Systemic candidiasis is a major public health concern. In particular, in immunocompromised people, such as patients with neutropenia, patients with Acquired Immune Deficiency Syndrome (AIDS) and cancer who are undergoing antiballistic chemotherapy or bone marrow transplants, and people with diabetes. Since the clinical signs and symptoms are nonspecific, early diagnosis is often difficult. The 65-kDa mannoprotein (MP65) gene of Candida albicans is appropriate for detection and identification of systemic candidiasis. This gene encodes a putative b-glucanase mannoprotein of 65 kDa, which plays a major role in the host-fungus relationship, morphogenesis and pathogenicity. The current study aimed to identify different species of Candida (C. albicans, C. glabrata and C. parapsilosis) using the Polymerase Chain Reaction (PCR) technique and also to evaluate C. albicans MP65 gene expression in BALB/C mice. All yeast isolates were identified on cornmeal agar supplemented with tween-80, germ tube formation in serum, and assimilation of carbon sources in the API 20 C AUX yeast identification system. Polymerase Chain Reaction was performed on all samples using species-specific primers for the MP65 65 kDa gene. After RNA extraction, cDNA synthesis was performed by the Maxime RT Pre Mix kit. Candida albicans MP65 gene expression was evaluated by quantitative Real-Time (q Real-Time) and Real-Time (RT) PCR techniques. The 2-ΔΔCT method was used to analyze relative changes in gene expression of MP65. For statistical analysis, nonparametric Wilcoxon test was applied using the SPSS version 16 software. Using biochemical methods, one hundred, six and one isolates of clinical samples were determined as C. albicans, C. glabrata and C. parapsilosis, respectively. Species-specific primers for PCR experiments were applied to clinical specimens, and in all cases a single expected band for C. albicans, C. glabrata and C. parapsilosis was obtained (475, 361 and 124 base pairs, respectively

Alcoholic fermentation of d-xylose by yeasts. [Brettanomyces naardenensis; Candida shehatae; Candida tenuis; Pachysolen tannaphilus, Pichia segobiensis; Pichia stipitis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Toivola, A.; Yarrow, D.; van den Bosch, E.

1984-06-01

Type strains of 200 species of yeasts able to ferment glucose and grow on xylose were screened for fermentation of D-xylose. In most of the strains tested, ethanol production was negligible. Nineteen were found to produce between 0.1 and 1.0 g of ethanol per liter. Strains of the following species produce more than 1 g of ethanol per liter in the fermentation test with 2% xylose: Brettanomyces naardenensis, Candida shehatae, Candida tenuis, Pachysolen tannophilus, Pichia segobiensis, and Pichia stipitis. Subsequent screening of these yeasts for their capacity to ferment D-cellobiose revealed that only Candida tenuis CBS 4435 was a goodmore » fermenter of both xylose and cellobiose under the test conditions used.« less

Probing the Active Site of Candida Glabrata Dihydrofolate Reductase with High Resolution Crystal Structures and the Synthesis of New Inhibitors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, J.; Bolstad, D; Smith, A

2009-01-01

Candida glabrata, a fungal strain resistant to many commonly administered antifungal agents, has become an emerging threat to human health. In previous work, we validated that the essential enzyme, dihydrofolate reductase, is a drug target in C. glabrata. Using a crystal structure of dihydrofolate reductase from C. glabrata bound to an initial lead compound, we designed a class of biphenyl antifolates that potently and selectively inhibit both the enzyme and the growth of the fungal culture. In this work, we explore the structure-activity relationships of this class of antifolates with four new high resolution crystal structures of enzyme:inhibitor complexes andmore » the synthesis of four new inhibitors. The designed inhibitors are intended to probe key hydrophobic pockets visible in the crystal structure. The crystal structures and an evaluation of the new compounds reveal that methyl groups at the meta and para positions of the distal phenyl ring achieve the greatest number of interactions with the pathogenic enzyme and the greatest degree of selectivity over the human enzyme. Additionally, antifungal activity can be tuned with substitution patterns at the propargyl and para-phenyl positions.« less

[Fluconazole and itraconazole susceptibility testing with clinical yeast isolates and algae of the genus Prototheca by means of the Etest].

PubMed

Blaschke-Hellmessen, R

1996-01-01

Preliminary own results suggest, that the Etest (produced by AB BIODISK, Solna, Sweden) performed on casitone medium meets the requirements of a routine test of yeast susceptibility to fluconazole and itraconazole. Testing of 46 clinical yeast isolates, of 5 strains of Exophiala dermatitidis and 4 strains of algae of the genus Prototheca revealed species-, genus- and strain-specific variations of the susceptibility to fluconazole and itraconazole. Candida glabrata was less susceptible to both triazoles than the other Candida species with exception of Candida krusei. Exophiala dermatitidis was highly susceptible to itraconazole. Prototheca wickerhamii and P. zopfii were resistant to both triazoles. Casitone medium is most appropriate for the determination of susceptibility to fluconazole and itraconazole by the Etest. The results of the Etest were comparable with those of a breakpoint test (microdilution method).

[Evaluation of PNA-FISH method for direct identification of Candida species in blood culture samples and its potential impact on guidance of antifungal therapy].

PubMed

Doğan, Özlem; İnkaya, Ahmet Çağkan; Gülmez, Dolunay; Uzun, Ömrüm; Akova, Murat; Arıkan Akdağlı, Sevtap

2016-10-01

Early antifungal therapy has a major influence on survival in candidemia. Rapid identification of the species has importance for the treatment, prediction of the species-specific primary resistance and variable antifungal susceptibility. Recently, molecular-based methods attempt to reduce the time between the positive signal of a blood culture and identification of the fungus. PNA-FISH (Peptide nucleic acid fluorescence in situ hybridization) assay distinguishes a number of frequently isolated Candida species in groups following the growth in blood culture. The aim of this study was to investigate the correlation of the species identified by PNA-FISH with conventional identification methods in yeast positive blood cultures and its influence on the selection of antifungal therapy. Specimens of adult patients diagnosed as yeast with Gram stain in signal-positive blood cultures between August to December 2013, were included in the study. The strains were concomitantly cultivated by subculturing from the blood culture bottles onto solid media and identified by conventional methods (germ tube test, ID32C and morphology on cornmeal Tween 80 agar). Rapid species identification was performed by Yeast Traffic Light PNA-FISH, which generates green flourescence for Candida albicans and Candida parapsilosis, yellow for Candida tropicalis, and red for Candida krusei and Candida glabrata. C.tropicalis was identified as a single species whereas the others were identified in pairs. The time points when the yeast positive blood culture bottle was received by the mycology laboratory and reporting of the species identification results by PNA-FISH and the conventional methods were recorded. Seven C.albicans, six C.glabrata, three C.parapsilosis, one C.tropicalis, one C.krusei, one Cryptococcus neoformans, one Saprochaete capitata (Blastoschizomyces capitatus), one C.albicans and Candida dubliniensis, one C.krusei and C.dubliniensis, and one C.glabrata and C.parapsilosis were

Normal yeast flora of the upper digestive tract of some wild columbids

USGS Publications Warehouse

Kocan, R.M.; Hasenclever, H.F.

1972-01-01

Seven species of pigeons and doves were cultured for yeasts in the upper digestive tract. The following list gives the isolation rate for each columbid species and the yeasts cultured from them: feral pigeon Columba Livia (Gmelin) 95% -Candida albicans (Robin) Berkhout, C. tropicalis (Castellani) Berkhout, C. krusei (Cast.) Berkhout, C. guilliermondii (Cast.) Langeron et Guerra, Torulopsis glabrata (Anderson) Lodder et De Vries, Saccharomyces telluris Van der Walt, and Geotrichum sp.; white-crowned pigeon (C. leucocephala Linnaeus) 56% -- S. telluris; mourning dove (Zenaidura rnacroura Linnaeus) 24% -- C. albicans, C. tropicalis, C. guilliermondii, and Geotrichurn sp.; passerine ground dove (Collumbigallina passerina Linnaeus) 20% -- C. parapsilosis (Ashford) Langeron et Talice, Kloeckera apiculata (Reess Emend. Klocker) Janke; zenaida dove (Zenaida aurita Temminck) 16% -- C. albicans, C. guilliermondii, and T. glabrata; one moustasche dove (Geotrygon mystacea Gosse) -- C. guillierrnondii; ringed turtle dove (Streptopelia rizoria Linnaeus) 14% -- C. albicans and Geotrichurn sp. No signs of disease could be seen in the 139 birds that were examined, and it was concluded that these yeasts comprise a part of the columbid's normal microbial flora.

Torulopsis glabrata infections in Singapore: a 4-year study.

PubMed

Tan, R J; Lim, E W; Teo, H K

1977-04-01

During the period 1971-4, Torulopsis glabrata formed 42% of yeasts isolated from 5677 clinical specimens from patients with cancers, diabetes mellitus, chronic renal failure, pregnacy or major surgical operations complicated by mycotic infections. The significance of T. glabrata in these patients is discussed.

Global Analysis of the Evolution and Mechanism of Echinocandin Resistance in Candida glabrata

PubMed Central

Singh-Babak, Sheena D.; Babak, Tomas; Diezmann, Stephanie; Hill, Jessica A.; Xie, Jinglin Lucy; Chen, Ying-Lien; Poutanen, Susan M.; Rennie, Robert P.; Heitman, Joseph; Cowen, Leah E.

2012-01-01

The evolution of drug resistance has a profound impact on human health. Candida glabrata is a leading human fungal pathogen that can rapidly evolve resistance to echinocandins, which target cell wall biosynthesis and are front-line therapeutics for Candida infections. Here, we provide the first global analysis of mutations accompanying the evolution of fungal drug resistance in a human host utilizing a series of C. glabrata isolates that evolved echinocandin resistance in a patient treated with the echinocandin caspofungin for recurring bloodstream candidemia. Whole genome sequencing identified a mutation in the drug target, FKS2, accompanying a major resistance increase, and 8 additional non-synonymous mutations. The FKS2-T1987C mutation was sufficient for echinocandin resistance, and associated with a fitness cost that was mitigated with further evolution, observed in vitro and in a murine model of systemic candidemia. A CDC6-A511G(K171E) mutation acquired before FKS2-T1987C(S663P), conferred a small resistance increase. Elevated dosage of CDC55, which acquired a C463T(P155S) mutation after FKS2-T1987C(S663P), ameliorated fitness. To discover strategies to abrogate echinocandin resistance, we focused on the molecular chaperone Hsp90 and downstream effector calcineurin. Genetic or pharmacological compromise of Hsp90 or calcineurin function reduced basal tolerance and resistance. Hsp90 and calcineurin were required for caspofungin-dependent FKS2 induction, providing a mechanism governing echinocandin resistance. A mitochondrial respiration-defective petite mutant in the series revealed that the petite phenotype does not confer echinocandin resistance, but renders strains refractory to synergy between echinocandins and Hsp90 or calcineurin inhibitors. The kidneys of mice infected with the petite mutant were sterile, while those infected with the HSP90-repressible strain had reduced fungal burden. We provide the first global view of mutations accompanying the

Yeasts isolated from Algerian infants's feces revealed a burden of Candida albicans species, non-albicans Candida species and Saccharomyces cerevisiae.

PubMed

Seddik, Hamza Ait; Ceugniez, Alexandre; Bendali, Farida; Cudennec, Benoit; Drider, Djamel

2016-01-01

This study aimed at showing the yeast diversity in feces of Algerian infants, aged between 1 and 24 months, hospitalized at Bejaia hospital (northeast side of the country). Thus, 20 colonies with yeast characteristics were isolated and identified using biochemical (ID32C Api system) and molecular (sequencing of ITS1-5.8S-ITS2 region) methods. Almost all colonies isolated (19 strains) were identified as Candida spp., with predominance of Candida albicans species, and one strain was identified as Saccharomyces cerevisiae. Screening of strains with inhibitory activities unveiled the potential of Candida parapsilosis P48L1 and Candida albicans P51L1 to inhibit the growth of Escherichia coli ATCC 25922 and Staphylococcus aureus ATCC 25923. Further studies performed with these two Candida strains revealed their susceptibility to clinically used antifungal compounds and were then characterized for their cytotoxicity and hemolytic properties. On the other hand, Saccharomyces cerevisiae P9L1 isolated as well in this study was shown to be devoid of antagonism but resulted safe and overall usable as probiotic.

Torulopsis glabrata infections in Singapore: a 4-year study.

PubMed Central

Tan, R. J.; Lim, E. W.; Teo, H. K.

1977-01-01

During the period 1971-4, Torulopsis glabrata formed 42% of yeasts isolated from 5677 clinical specimens from patients with cancers, diabetes mellitus, chronic renal failure, pregnacy or major surgical operations complicated by mycotic infections. The significance of T. glabrata in these patients is discussed. PMID:265338

Limitations of the Current Microbial Identification System for Identification of Clinical Yeast Isolates

PubMed Central

Kellogg, James A.; Bankert, David A.; Chaturvedi, Vishnu

1998-01-01

The ability of the rapid, computerized Microbial Identification System (MIS; Microbial ID, Inc.) to identify a variety of clinical isolates of yeast species was compared to the abilities of a combination of tests including the Yeast Biochemical Card (bioMerieux Vitek), determination of microscopic morphology on cornmeal agar with Tween 80, and when necessary, conventional biochemical tests and/or the API 20C Aux system (bioMerieux Vitek) to identify the same yeast isolates. The MIS chromatographically analyzes cellular fatty acids and compares the results with the fatty acid profiles in its database. Yeast isolates were subcultured onto Sabouraud dextrose agar and were incubated at 28°C for 24 h. The resulting colonies were saponified, methylated, extracted, and chromatographically analyzed (by version 3.8 of the MIS YSTCLN database) according to the manufacturer’s instructions. Of 477 isolates of 23 species tested, 448 (94%) were given species names by the MIS and 29 (6%) were unidentified (specified as “no match” by the MIS). Of the 448 isolates given names by the MIS, only 335 (75%) of the identifications were correct to the species level. While the MIS correctly identified only 102 (82%) of 124 isolates of Candida glabrata, the predictive value of an MIS identification of unknown isolates as C. glabrata was 100% (102 of 102) because no isolates of other species were misidentified as C. glabrata. In contrast, while the MIS correctly identified 100% (15 of 15) of the isolates of Saccharomyces cerevisiae, the predictive value of an MIS identification of unknown isolates as S. cerevisiae was only 47% (15 of 32), because 17 isolates of C. glabrata were misidentified as S. cerevisiae. The low predictive values for accuracy associated with MIS identifications for most of the remaining yeast species indicate that the procedure and/or database for the system need to be improved. PMID:9574676

Enhanced pyruvate production in Candida glabrata by carrier engineering.

PubMed

Luo, Zhengshan; Liu, Song; Du, Guocheng; Xu, Sha; Zhou, Jingwen; Chen, Jian

2018-02-01

Pyruvate is an important organic acid that plays a key role in the central metabolic pathway. Manipulating transporters is an efficient strategy to enhance production of target organic acids and a means to understand the effects of altered intracellular pyruvate content on global metabolic networks. Efforts have been made to manipulate mitochondrial pyruvate carrier (MPC) to transport pyruvate into different subcellular compartments in Candida glabrata to demonstrate the effects of the subcellular distribution of pyruvate on central carbon metabolism. By increasing the mitochondrial pyruvate content through enhancing the rate of pyruvate transport into mitochondria, a high central carbon metabolism rate, specific growth rate and specific pyruvate production rate were obtained. Comparing the intracellular pyruvate content of engineered and control strains showed that higher intracellular pyruvate levels were not conducive to improving pyruvate productivity or central carbon metabolism. Plasma membrane expression of MPCs significantly increased the expression levels of key rate-limiting glycolytic enzymes. Moreover, pyruvate production of CGΔura3-Sp-MPC1, CGΔura3-Sp-MPC2, and CGΔura3-Sp-MPC1-Sp-MPC2 increased 134.4%, 120.3%, and 30.0%, respectively. In conclusion, lower intracellular pyruvate content enhanced central carbon metabolism and provided useful clues for improving the production of other organic acids in microorganisms. © 2017 Wiley Periodicals, Inc.

Evaluation of the Microbial Identification System for identification of clinically isolated yeasts.

PubMed Central

Crist, A E; Johnson, L M; Burke, P J

1996-01-01

The Microbial Identification System (MIS; Microbial ID, Inc., Newark, Del.) was evaluated for the identification of 550 clinically isolated yeasts. The organisms evaluated were fresh clinical isolates identified by methods routinely used in our laboratory (API 20C and conventional methods) and included Candida albicans (n = 294), C. glabrata (n = 145), C. tropicalis (n = 58), C. parapsilosis (n = 33), and other yeasts (n = 20). In preparation for fatty acid analysis, yeasts were inoculated onto Sabouraud dextrose agar and incubated at 28 degrees C for 24 h. Yeasts were harvested, saponified, derivatized, and extracted, and fatty acid analysis was performed according to the manufacturer's instructions. Fatty acid profiles were analyzed, and computer identifications were made with the Yeast Clinical Library (database version 3.8). Of the 550 isolates tested, 374 (68.0%) were correctly identified to the species level, with 87 (15.8%) being incorrectly identified and 89 (16.2%) giving no identification. Repeat testing of isolates giving no identification resulted in an additional 18 isolates being correctly identified. This gave the MIS an overall identification rate of 71.3%. The most frequently misidentified yeast was C. glabrata, which was identified as Saccharomyces cerevisiae 32.4% of the time. On the basis of these results, the MIS, with its current database, does not appear suitable for the routine identification of clinically important yeasts. PMID:8880489

Chemical signaling and insect attraction is a conserved trait in yeasts.

PubMed

Becher, Paul G; Hagman, Arne; Verschut, Vasiliki; Chakraborty, Amrita; Rozpędowska, Elżbieta; Lebreton, Sébastien; Bengtsson, Marie; Flick, Gerhard; Witzgall, Peter; Piškur, Jure

2018-03-01

Yeast volatiles attract insects, which apparently is of mutual benefit, for both yeasts and insects. However, it is unknown whether biosynthesis of metabolites that attract insects is a basic and general trait, or if it is specific for yeasts that live in close association with insects. Our goal was to study chemical insect attractants produced by yeasts that span more than 250 million years of evolutionary history and vastly differ in their metabolism and lifestyle. We bioassayed attraction of the vinegar fly Drosophila melanogaster to odors of phylogenetically and ecologically distinct yeasts grown under controlled conditions. Baker's yeast Saccharomyces cerevisiae , the insect-associated species Candida californica , Pichia kluyveri and Metschnikowia andauensis , wine yeast Dekkera bruxellensis , milk yeast Kluyveromyces lactis , the vertebrate pathogens Candida albicans and Candida glabrata , and oleophilic Yarrowia lipolytica were screened for fly attraction in a wind tunnel. Yeast headspace was chemically analyzed, and co-occurrence of insect attractants in yeasts and flowering plants was investigated through a database search. In yeasts with known genomes, we investigated the occurrence of genes involved in the synthesis of key aroma compounds. Flies were attracted to all nine yeasts studied. The behavioral response to baker's yeast was independent of its growth stage. In addition to Drosophila , we tested the basal hexapod Folsomia candida (Collembola) in a Y-tube assay to the most ancient yeast, Y. lipolytica, which proved that early yeast signals also function on clades older than neopteran insects. Behavioral and chemical data and a search for selected genes of volatile metabolites underline that biosynthesis of chemical signals is found throughout the yeast clade and has been conserved during the evolution of yeast lifestyles. Literature and database reviews corroborate that yeast signals mediate mutualistic interactions between insects and yeasts

Oral yeast colonization in peritoneal dialysis and hemodialysis patients and renal transplant recipients.

PubMed

Gulcan, Aynur; Gulcan, Erim; Keles, Mustafa; Aktas, Esin

2016-06-01

We aimed to investigate the frequency of oral yeast colonization (OYC) and the risk factors for patients who received continuous ambulatory peritoneal dialysis (CAPD) or hemodialysis (HD) or were renal transplant recipients (RTRs). The patients admitted to the Nephrology Clinic at Ataturk University Medical School from January through April 2013 were included in the study. A questionnaire about risk factors was filled out, and swab cultures were taken from the tongue surface of each participant. OYC was detected in 32.1% of the RTRs, 40% of the HD patients, 20.9% of the CAPD patients, and 18% of the healthy control (HC) group. Of the 42 yeast strains isolated from the renal replacement therapy groups, 26 strains (61.9%) were Candida albicans, nine (21.4%) were Candida glabrata, two (4.7%) were Candida krusei, two (4.7%) were Candida kefyr, one (2.38%) was Candida parapsilosis, and two (4.7%) were Geotrichum candidum. Risk factors for OYC in the RTRs group included antibiotic use and the presence of dental prostheses; however, in patients with chronic renal failure undergoing CAPD, only the presence of dental prostheses was found to be a statistically significant risk factor. Although OYC was mostly detected in patients with chronic kidney disease (undergoing HD, a variety of isolated yeast strains in the RTRs was noted. The rates of OYC and isolated Candida species in CAPD were similar to those of the HC group. Copyright © 2016 Elsevier Ltd. All rights reserved.

Water quality and antifungal susceptibility of opportunistic yeast pathogens from rivers.

PubMed

Monapathi, M E; Bezuidenhout, C C; Rhode, O H J

2017-03-01

Yeasts from water sources have been associated with diseases ranging from superficial mucosal infections to life threatening diseases. The aim of this study was to determine the water quality as well as diversity and antifungal susceptibility of yeasts from two rivers. Yeast levels and physico-chemical parameter data were analyzed by principal component analysis to determine correlations between physico-chemical data and yeast levels. Yeast morphotypes were identified by biochemical tests and 26S rRNA gene sequencing. Disk diffusion antifungal susceptibility tests were conducted. Physico-chemical parameters of the water were within target water quality range (TWQR) for livestock farming. For irrigational use, total dissolved solids and nitrates were not within the TWQR. Yeast levels ranged between 27 ± 10 and 2,573 ± 306 cfu/L. Only non-pigmented, ascomycetous yeasts were isolated. Saccharomyces cerevisiae and Candida glabrata were most frequently isolated. Several other opportunistic pathogens were also isolated. A large number of isolates were resistant to azoles, especially fluconazole, but also to other antifungal classes. Candida species were resistant to almost all the antifungal classes. These water sources are used for recreation and religious as well as for watering livestock and irrigation. Of particular concern is the direct contact of individuals with opportunistic yeast, especially the immune-compromised. Resistance of these yeast species to antifungal agents is a further health concern.

A CTG Clade Candida Yeast Genetically Engineered for the Genotype-Phenotype Characterization of Azole Antifungal Resistance in Human-Pathogenic Yeasts.

PubMed

Accoceberry, Isabelle; Rougeron, Amandine; Biteau, Nicolas; Chevrel, Pauline; Fitton-Ouhabi, Valérie; Noël, Thierry

2018-01-01

A strain of the opportunistic pathogenic yeast Candida lusitaniae was genetically modified for use as a cellular model for assessing by allele replacement the impact of lanosterol C14α-demethylase ERG11 mutations on azole resistance. Candida lusitaniae was chosen because it is susceptible to azole antifungals, it belongs to the CTG clade of yeast, which includes most of the Candida species pathogenic for humans, and it is haploid and easily amenable to genetic transformation and molecular modeling. In this work, allelic replacement is targeted at the ERG11 locus by the reconstitution of a functional auxotrophic marker in the 3' intergenic region of ERG11 Homologous and heterologous ERG11 alleles are expressed from the resident ERG11 promoter of C. lusitaniae , allowing accurate comparison of the phenotypic change in azole susceptibility. As a proof of concept, we successfully expressed in C. lusitaniae different ERG11 alleles, either bearing or not bearing mutations retrieved from a clinical context, from two phylogenetically distant yeasts, C. albicans and Kluyveromyces marxianus Candida lusitaniae constitutes a high-fidelity expression system, giving specific Erg11p-dependent fluconazole MICs very close to those observed with the ERG11 donor strain. This work led us to characterize the phenotypic effect of two kinds of mutation: mutation conferring decreased fluconazole susceptibility in a species-specific manner and mutation conferring fluconazole resistance in several yeast species. In particular, a missense mutation affecting amino acid K143 of Erg11p in Candida species, and the equivalent position K151 in K. marxianus , plays a critical role in fluconazole resistance. Copyright © 2017 American Society for Microbiology.

Antifungal Activity of Propolis Against Yeasts Isolated From Blood Culture: In Vitro Evaluation.

PubMed

Mutlu Sariguzel, Fatma; Berk, Elife; Koc, Ayes Nedret; Sav, Hafize; Demir, Gonca

2016-09-01

Due to the failure of available antifungal agents in the treatment of candidemia and the toxic activities of these drugs, a lot of researches are being conducted to develop new nontoxic and effective antifungal agents for optimal control of fungal pathogens. The aim of this study is to evaluate the in vitro antifungal activity of propolis against yeasts isolated from the blood cultures of intensive care unit patients. Seventy-six strains were included in this study. The in vitro antifungal activity of propolis, fluconazole (FLU), and itraconazole (ITR) was investigated by the microdilution broth methods (CLSI guidelines M27-A3 for yeast). The propolis sample was collected from Kayseri, Turkey. Of the 76 isolates, 33 were identified as Candida albicans while 37 were C. parapsilosis, three were C. tropicalis, and three were identified as C. glabrata. The geometric mean range for MIC (μg/ml) with regard to all isolates was 0.077 to 3 μg/ml for FLU and ITR, and 0.375 to 0.70 μg/ml for propolis. It was shown that propolis had significant antifungal activity against all Candida strains and the MIC range of propolis was determined as 0185 to 3 μg/ml. This study demonstrated that propolis had significant antifungal activity against yeasts isolated from blood culture compared with FLU and ITR. The propolis MIC in azole-resistant strains such as C. glabrata was found lower than the FLU MIC. © 2015 Wiley Periodicals, Inc.

Candida spencermartinsiae sp. nov., Candida taylorii sp. nov. and Pseudozyma abaconensis sp. nov., novel yeasts from mangrove and coral reef ecosystems.

PubMed

Statzell-Tallman, Adele; Scorzetti, Gloria; Fell, Jack W

2010-08-01

Three species of yeasts are taxonomically described for strains isolated from marine environments. Candida spencermartinsiae sp. nov. (type strain CBS 10894T =NRRL Y-48663T) and Candida taylorii sp. nov. (type strain CBS 8508T =NRRL Y-27213T) are anamorphic ascomycetous yeasts in a phylogenetic cluster of marine yeasts in the Debaryomyces/Lodderomyces clade of the Saccharomycetales. The two species were isolated from multiple locations among coral reefs and mangrove habitats. Pseudozyma abaconensis sp. nov. (type strain CBS 8380T =NRRL Y-17380T) is an anamorphic basidiomycete that is related to the smut fungi of the genus Ustilago in the Ustilaginales. P. abaconensis was collected from waters adjacent to a coral reef.

Synergistic and antagonistic effects of immunomodulatory drugs on the action of antifungals against Candida glabrata and Saccharomyces cerevisiae.

PubMed

Tome, Miha; Zupan, Jure; Tomičić, Zorica; Matos, Tadeja; Raspor, Peter

2018-01-01

Candidemia and other forms of invasive fungal infections caused by Candida glabrata and to a lesser extent Saccharomyces cerevisiae are a serious health problem, especially if their steadily rising resistance to the limited range of antifungal drugs is taken into consideration. Various drug combinations are an attractive solution to the resistance problem, and some drug combinations are already common in the clinical environment due to the nature of diseases or therapies. We tested a few of the common antifungal-immunomodulatory drug combinations and evaluated their effect on selected strains of C. glabrata and S. cerevisiae . The combinations were performed using the checkerboard microdilution assay and interpreted using the Loewe additivity model and a model based on the Bliss independence criterion. A synergistic interaction was confirmed between calcineurin inhibitors (Fk506 and cyclosporine A) and antifungals (fluconazole, itraconazole, and amphotericin B). A new antagonistic interaction between mycophenolic acid (MPA) and azole antifungals was discovered in non-resistant strains. A possible mechanism that explains this is induction of the Cdr1 efflux pump by MPA in C. glabrata ATCC 2001. The Pdr1 regulatory cascade plays a role in overall resistance to fluconazole, but it is not essential for the antagonistic interaction. This was confirmed by the Cg pdr1 Δ mutant still displaying the antagonistic interaction between the drugs, although at lower concentrations of fluconazole. This antagonism calls into question the use of simultaneous therapy with MPA and azoles in the clinical environment.

Regulation of the CgPdr1 Transcription Factor from the Pathogen Candida glabrata ▿

PubMed Central

Paul, Sanjoy; Schmidt, Jennifer A.; Moye-Rowley, W. Scott

2011-01-01

Candida glabrata is an opportunistic human pathogen that is increasingly associated with candidemia, owing in part to the intrinsic and acquired high tolerance the organism exhibits for the important clinical antifungal drug fluconazole. This elevated fluconazole resistance often develops through gain-of-function mutations in the zinc cluster-containing transcriptional regulator C. glabrata Pdr1 (CgPdr1). CgPdr1 induces the expression of an ATP-binding cassette (ABC) transporter-encoding gene, CgCDR1. Saccharomyces cerevisiae has two CgPdr1 homologues called ScPdr1 and ScPdr3. These factors control the expression of an ABC transporter-encoding gene called ScPDR5, which encodes a homologue of CgCDR1. Loss of the mitochondrial genome (ρ0 cell) or overexpression of the mitochondrial enzyme ScPsd1 induces ScPDR5 expression in a strictly ScPdr3-dependent fashion. ScPdr3 requires the presence of a transcriptional Mediator subunit called Gal11 (Med15) to fully induce ScPDR5 transcription in response to ρ0 signaling. ScPdr1 does not respond to either ρ0 signals or ScPsd1 overproduction. In this study, we employed transcriptional fusions between CgPdr1 target promoters, like CgCDR1, to demonstrate that CgPdr1 stimulates gene expression via binding to elements called pleiotropic drug response elements (PDREs). Deletion mapping and electrophoretic mobility shift assays demonstrated that a single PDRE in the CgCDR1 promoter was capable of supporting ρ0-induced gene expression. Removal of one of the two ScGal11 homologues from C. glabrata caused a major defect in drug-induced expression of CgCDR1 but had a quantitatively minor effect on ρ0-stimulated transcription. These data demonstrate that CgPdr1 appears to combine features of ScPdr1 and ScPdr3 to produce a transcription factor with chimeric regulatory properties. PMID:21131438

Candida olivae sp. nov., a novel yeast species from 'Greek-style' black olive fermentation.

PubMed

Nisiotou, Aspasia A; Panagou, Efstathios Z; Nychas, George-John E

2010-05-01

Two yeast strains (FMCC Y-1(T) and FMCC Y-2) were recovered during a survey of the yeast biota associated with fermenting black olives, collected from an olive tree (Olea europaea L. cv. 'Conservolea') orchard in Central Greece. Phylogenetic analysis based on rRNA gene sequences (18S, 26S, and 5.8S-ITS) indicated that the two strains represent a separate species within the Candida membranifaciens clade, in close relation to Candida blattariae NRRL Y-27703(T). Electrophoretic karyotyping and physiological analysis support the affiliation of the two strains to a novel species as Candida olivae sp. nov. The novel strains are conspecific with two Candida sp. strains previously isolated from the Mid-Atlantic Ridge hydrothermal fields [Gadanho & Sampaio (2005). Microb Ecol 50, 408-417], indicating that Candida olivae sp. nov. may occupy diverse ecological niches. FMCC Y-1(T) (=CBS 11171(T) =ATCC MYA-4568(T)) is the type strain.

Overcoming the heterologous bias: An in vivo functional analysis of multidrug efflux transporter, CgCdr1p in matched pair clinical isolates of Candida glabrata

DOE Office of Scientific and Technical Information (OSTI.GOV)

Puri, Nidhi; Manoharlal, Raman; Sharma, Monika

2011-01-07

Research highlights: {yields} First report to demonstrate an in vivo expression system of an ABC multidrug transporter CgCdr1p of C. glabrata. {yields} First report on the structure and functional characterization of CgCdr1p. {yields} Functional conservation of divergent but typical residues of CgCdr1p. {yields} CgCdr1p elicits promiscuity towards substrates and has a large drug binding pocket with overlapping specificities. -- Abstract: We have taken advantage of the natural milieu of matched pair of azole sensitive (AS) and azole resistant (AR) clinical isolates of Candida glabrata for expressing its major ABC multidrug transporter, CgCdr1p for structure and functional analysis. This was accomplishedmore » by tagging a green fluorescent protein (GFP) downstream of ORF of CgCDR1 and integrating the resultant fusion protein at its native chromosomal locus in AS and AR backgrounds. The characterization confirmed that in comparison to AS isolate, CgCdr1p-GFP was over-expressed in AR isolates due to its hyperactive native promoter and the GFP tag did not affect its functionality in either construct. We observed that in addition to Rhodamine 6 G (R6G) and Fluconazole (FLC), a recently identified fluorescent substrate of multidrug transporters Nile Red (NR) could also be expelled by CgCdr1p. Competition assays with these substrates revealed the presence of overlapping multiple drug binding sites in CgCdr1p. Point mutations employing site directed mutagenesis confirmed that the role played by unique amino acid residues critical to ATP catalysis and localization of ABC drug transporter proteins are well conserved in C. glabrata as in other yeasts. This study demonstrates a first in vivo novel system where over-expression of GFP tagged MDR transporter protein can be driven by its own hyperactive promoter of AR isolates. Taken together, this in vivo system can be exploited for the structure and functional analysis of CgCdr1p and similar proteins wherein the arte

Species distribution and susceptibility profile to fluconazole, voriconazole and MXP-4509 of 551 clinical yeast isolates from a Romanian multi-centre study.

PubMed

Minea, B; Nastasa, V; Moraru, R F; Kolecka, A; Flonta, M M; Marincu, I; Man, A; Toma, F; Lupse, M; Doroftei, B; Marangoci, N; Pinteala, M; Boekhout, T; Mares, M

2015-02-01

This is the first multi-centre study regarding yeast infections in Romania. The aim was to determine the aetiological spectrum and susceptibility pattern to fluconazole, voriconazole and the novel compound MXP-4509. The 551 isolates were identified using routine laboratory methods, matrix-assisted laser desorption ionisation time-of-flight mass spectrometry (MALDI-TOF MS) and DNA sequence analysis. Susceptibility testing was performed using the European Committee for Antimicrobial Susceptibility Testing (EUCAST) method and breakpoints. The yeasts originated from superficial infections (SUP, 51.5 %), bloodstream infections (BSI, 31.6 %) and deep-seated infections (DEEP, 16.9 %), from patients of all ages. Nine genera and 30 species were identified. The 20 Candida species accounted for 94.6 % of all isolates. C. albicans was the overall leading pathogen (50.5 %). Lodderomyces elongisporus is reported for the first time as a fungaemia cause in Europe. C. glabrata and Saccharomyces cerevisiae, as well as the non-Candida spp. and non-albicans Candida spp. groups, showed decreased fluconazole susceptibility (<75 %). The overall fluconazole resistance was 10.2 %. C. krusei accounted for 27 of the 56 fluconazole-resistant isolates. The overall voriconazole resistance was 2.5 % and was due mainly to C. glabrata and C. tropicalis isolates. Fluconazole resistance rates for the three categories of infection were similar to the overall value; voriconazole resistance rates differed: 4 % for BSI, 3.2 % for DEEP and 1.4 % for SUP. The antifungal activity of MXP-4509 was superior to voriconazole against C. glabrata and many fluconazole-resistant isolates. There was a large percentage of non-albicans Candida isolates. A large part of the high fluconazole resistance was not acquired but intrinsic, resulting from the high percentage of C. krusei.

Oxygen requirements of yeasts. [Saccharomyces cerevisiae; Candida tropicalis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Visser, W.; Scheffers, W.A.; Batenburg-Van Der Vegte, W.H.

1990-12-01

Type species of 75 yeast genera were examined for their ability to grow anaerobically in complex and mineral media. To define anaerobic conditions, we added a redox indicator, resazurin, to the media to determine low redox potentials. All strains tested were capable of fermenting glucose to ethanol in oxygen-limited shake-flask cultures, even those of species generally regarded as nonfermentative. However, only 23% of the yeast species tested grew under anaerobic conditions. A comparative study with a number of selected strains revealed that Saccharomyces cerevisiae stands out as a yeast capable of rapid growth at low redox potentials. Other yeasts, suchmore » as Torulaspora delbrueckii and Candida tropicalis, grew poorly ({mu}{sub max}, 0.03 and 0.05 h{sup {minus}1}, respectively) under anaerobic conditions in mineral medium supplemented with Tween 80 and ergosterol. The latter organisms grew rapidly under oxygen limitation and then displayed a high rate of alcoholic fermentation. It can be concluded that these yeasts have hitherto-unidentified oxygen requirements for growth.« less

Candida aechmeae sp. nov. and Candida vrieseae sp. nov., novel yeast species isolated from the phylloplane of bromeliads in Southern Brazil.

PubMed

Landell, Melissa Fontes; Billodre, Raisa; Ramos, Jesus P; Leoncini, Orílio; Vainstein, Marilene H; Valente, Patrícia

2010-01-01

Two novel yeast species, Candida aechmeae sp. nov. and Candida vrieseae sp. nov., were isolated from bromeliads in Itapuã Park, Rio Grande do Sul, Brazil. These species are genetically isolated from all other currently recognized ascomycetous yeasts based on their sequence divergence in the D1/D2 domain of the LSU rRNA gene. C. aechmeae sp. nov. is phylogenetically close to Candida ubatubensis, a species also isolated from bromeliads in Brazil, but the novel species can be differentiated on the basis of differences in the D1/D2 domain and positive results for the assimilation of l-arabinose, raffinose, inulin and citrate. Candida vrieseae sp. nov. is phylogenetically placed in a clade near Candida membranifaciens that is composed of several species associated with insects, but the novel species can be differentiated from them by the D1/D2 and ITS gene sequences, positive results for the assimilation of nitrite and a negative result for the assimilation of ethylamine. The type strain for Candida aechmeae sp. nov. is BI153(T) (=CBS 10831(T)=NRRL Y-48456(T)) and the type strain for C. vrieseae sp. nov. is BI146(T) (=CBS 10829(T)=NRRL Y-48461(T)).

Candida Biofilms: Threats, Challenges, and Promising Strategies.

PubMed

Cavalheiro, Mafalda; Teixeira, Miguel Cacho

2018-01-01

Candida species are fungal pathogens known for their ability to cause superficial and systemic infections in the human host. These pathogens are able to persist inside the host due to the development of pathogenicity and multidrug resistance traits, often leading to the failure of therapeutic strategies. One specific feature of Candida species pathogenicity is their ability to form biofilms, which protects them from external factors such as host immune system defenses and antifungal drugs. This review focuses on the current threats and challenges when dealing with biofilms formed by Candida albicans, Candida glabrata, Candida tropicalis , and Candida parapsilosis , highlighting the differences between the four species. Biofilm characteristics depend on the ability of each species to produce extracellular polymeric substances (EPS) and display dimorphic growth, but also on the biofilm substratum, carbon source availability and other factors. Additionally, the transcriptional control over processes like adhesion, biofilm formation, filamentation, and EPS production displays great complexity and diversity within pathogenic yeasts of the Candida genus. These differences not only have implications in the persistence of colonization and infections but also on antifungal resistance typically found in Candida biofilm cells, potentiated by EPS, that functions as a barrier to drug diffusion, and by the overexpression of drug resistance transporters. The ability to interact with different species in in vivo Candida biofilms is also a key factor to consider when dealing with this problem. Despite many challenges, the most promising strategies that are currently available or under development to limit biofilm formation or to eradicate mature biofilms are discussed.

Candida Biofilms: Threats, Challenges, and Promising Strategies

PubMed Central

Cavalheiro, Mafalda; Teixeira, Miguel Cacho

2018-01-01

Candida species are fungal pathogens known for their ability to cause superficial and systemic infections in the human host. These pathogens are able to persist inside the host due to the development of pathogenicity and multidrug resistance traits, often leading to the failure of therapeutic strategies. One specific feature of Candida species pathogenicity is their ability to form biofilms, which protects them from external factors such as host immune system defenses and antifungal drugs. This review focuses on the current threats and challenges when dealing with biofilms formed by Candida albicans, Candida glabrata, Candida tropicalis, and Candida parapsilosis, highlighting the differences between the four species. Biofilm characteristics depend on the ability of each species to produce extracellular polymeric substances (EPS) and display dimorphic growth, but also on the biofilm substratum, carbon source availability and other factors. Additionally, the transcriptional control over processes like adhesion, biofilm formation, filamentation, and EPS production displays great complexity and diversity within pathogenic yeasts of the Candida genus. These differences not only have implications in the persistence of colonization and infections but also on antifungal resistance typically found in Candida biofilm cells, potentiated by EPS, that functions as a barrier to drug diffusion, and by the overexpression of drug resistance transporters. The ability to interact with different species in in vivo Candida biofilms is also a key factor to consider when dealing with this problem. Despite many challenges, the most promising strategies that are currently available or under development to limit biofilm formation or to eradicate mature biofilms are discussed. PMID:29487851

Three anamorphic yeast species Candida sanitii sp. nov., Candida sekii sp. nov. and Candida suwanaritii, three novel yeasts in the Saturnispora clade isolated in Thailand.

PubMed

Limtong, Savitree; Kaewwichian, Rungluk; Am-In, Somjit; Boonmak, Chanita; Jindamorakot, Sasitorn; Yongmanitchai, Wichien; Srisuk, Natana; Kawasaki, Hiroko; Nakase, Takashi

2010-02-01

Nine strains of three novel anamorphic yeast species were obtained from samples collected in Thailand including six strains (RV96, RV152, R14, RS9, RS58 and EA1) obtained from estuarine waters collected from two mangrove forests, one strain (ST84) from insect frass and two strains (SR16 and UB13) from forest soils. On the basis of morphological, biochemical, physiological and chemotaxonomic characteristics, and the sequence analysis of the D1/D2 domain of the large subunit rRNA gene, the nine strains were found to represent three novel Candida species in the Saturnispora clade. Five strains (RV96, RV152, R14, RS9 and RS58) were assigned as a single novel species, which was named Candida sanitii sp. nov. The type strain is RV152(T) (BCC 25967(T)=NBRC 103864(T)=CBS 10864(T)). Strain EA1 was named as Candida suwanaritii sp. nov. The type strain is EA1(T) (BCC 29900(T)=NBRC 104877(T)=CBS 11021(T)). Three strains (ST84, SR16 and UB13) represented another novel species, for which Candida sekii sp. nov. is proposed. The type strain is ST84(T) (BCC 8320(T)=NBRC 105671(T)=CBS 10931(T)).

[Evaluation of common commercial systems for the identification of yeast isolates in microbiology laboratories: a multicenter study].

PubMed

Karabıçak, Nilgün; Uludağ Altun, Hatice; Karatuna, Onur; Hazırolan, Gülşen; Aksu, Neriman; Adiloğlu, Ali; Akyar, Işın

2015-04-01

Accurate and rapid identification of yeast isolates have become important in recent years for not only antifungal susceptibility testing due to the species-specific clinical resistance breakpoints but also early initiation of appropriate antifungal therapy. In clinical microbiology laboratories species identification of yeasts is often performed with several commercial systems based on biochemical properties and rarely according to the physiological and morphological characteristics. The aim of this study was to compare the two common commercial systems, VITEK 2 YST ID Card (Vitek; bioMérieux, France) and API 20C AUX (API; bioMérieux, France) with conventional mycological methods. A total of 473 clinical yeast strains isolated from clinical specimens in different university and training/research hospitals and identified by Vitek system were included in the study. The isolates were re-identified with API and conventional methods including morphological identification in the Mycology Reference Laboratory of the Public Health Institute of Turkey. Candida dubliniensis MYA 583, Candida krusei ATCC 6258, Candida parapsilosis ATCC 22019, Candida albicans ATCC 10231 and Cryptococcus neoformans ATCC 32268 were used as quality control strains and those standard strains were studied consecutively 10 days with both of the methods. The results of identification by Vitek and API were compared with the results of conventional methods for those 473 yeast isolates [6 genus (Candida, Cryptococcus, Blastoshizomyces, Rhodotorula, Saccharomyces, Trichosporon), 17 species (5 common and 12 rarely isolated)]. The performances of the systems were better (Vitek: 95%; API: 96%) for the commonly detected species (C.albicans, C.parapsilosis, C.glabrata, C.tropicalis and C.krusei) than those for rarely detected species (Vitek: 78.4%; API: 71.6%) (p= 0.155). Misidentification or unidentification were mostly detected for C.parapsilosis (Vitek: 6/87; API: 7/87) and C.glabrata (Vitek: 9/104; API

De Novo Assembly of Candida sojae and Candida boidinii Genomes, Unexplored Xylose-Consuming Yeasts with Potential for Renewable Biochemical Production

PubMed Central

Borelli, Guilherme; José, Juliana; Teixeira, Paulo José Pereira Lima; dos Santos, Leandro Vieira

2016-01-01

Candida boidinii and Candida sojae yeasts were isolated from energy cane bagasse and plague-insects. Both have fast xylose uptake rate and produce great amounts of xylitol, which are interesting features for food and 2G ethanol industries. Because they lack published genomes, we have sequenced and assembled them, offering new possibilities for gene prospection. PMID:26769937

Diversity and antifungal resistance patterns of prevalent opportunistic pathogenic yeasts colonizing the oral cavities of asymptomatic human immunodeficiency virus-infected individuals, and their relation to CD4+ counts

PubMed Central

Kumar, Deepa Anil; Muralidhar, Sumathi; Banerjee, Uma; Basir, Seemi Farhat; Mathur, Purva; Khan, Luqman Ahmad

2015-01-01

Background: Yeasts are important opportunistic pathogens, in individuals infected with human immunodeficiency virus (HIV). Yeast species inhabiting the oral mucosa of HIV-infected persons can act as source of oral lesions, especially as the individual progresses towards immunocompromised state. Present study was conducted to evaluate the diversity of yeasts in oral cavities of asymptomatic HIV-infected persons and their association with CD4+ cell counts. Materials and Methods: 100 HIV seropositive subjects and 100 healthy controls were screened for oral yeast carriage using standard procedures. Results: Of the 100 HIV-seropositive persons screened, 48 were colonized by different yeasts, either alone or in association with another species. Candida albicans was the most common species (56.90%) while non C. albicans Candida (NCAC) accounted for 39.65%. Among NCAC, Candida tropicalis and Candida krusei were most common. One isolate each of rare opportunistic pathogenic yeasts, Geotrichum candidum and Saccharomyces cereviseae, was recovered. The control group had an oral candidal carriage rate of 23%; C. albicans was the predominant species, followed by Candida glabrata, C. tropicalis and Candida parapsilosis. Antifungal susceptibility testing revealed no resistance in C. albicans, to the commonly used antifungal agents, whereas resistance or dose dependent susceptibility to fluconazole was observed in some of the NCAC species. Conclusion: Oral carriage of opportunistic pathogenic yeasts was greater in HIV-seropositive persons heading towards immunocompromised state, as evidenced by their CD4+ cell count. The predominant yeast isolated in this study (C. albicans), was found to be susceptible to commonly used antifungals. PMID:26392655

Prevalence of pathogenic yeasts and humoral antibodies to candida in diabetic patients.

PubMed Central

Odds, F C; Evans, E G; Taylor, M A; Wales, J K

1978-01-01

The prevalence of oral yeasts and humoral precipitating antibodies to candida was estimated in 204 unselected diabetic patients (172 outpatients and 32 inpatients). Yeasts, mainly Candida albicans, were isolated from the mouths of 41% of the outpatients and precipitins were found in 17.5% although none of the patients had clinically overt candidiasis. The extent of oral yeast colonisation and incidence of antibodies was not related to their antidiabetic treatment or to the duration of their diabetes. It was, however, related to the blood glucose and urine sugar levels at the time they were sampled, the highest incidence being among the diabetic inpatients with high blood glucose levels at the time of sampling and the lowest among outpatients with normal blood glucose levels at the time of sampling. There was no such correlation when diabetic control over the previous 12-month period was considered. PMID:711913

Candida saraburiensis sp. nov. and Candida prachuapensis sp. nov., xylose-utilizing yeast species isolated in Thailand.

PubMed

Nitiyon, Sukanya; Boonmak, Chanita; Am-In, Somjit; Jindamorakot, Sasitorn; Kawasaki, Hiroko; Yongmanitchai, Wichien; Limtong, Savitree

2011-02-01

Four strains of two novel xylose-utilizing yeast species were obtained from samples collected in Thailand from decaying corncobs (strains KU-Xs13(T) and KU-Xs18), a decaying grass (KU-Xs20) and estuarine water from a mangrove forest (WB15(T)). On the basis of morphological, biochemical, physiological and chemotaxonomic characteristics and sequence analysis of the D1/D2 domain of the large subunit rRNA gene, the four strains were found to represent two novel species of the genus Candida in the Candida albicans/Lodderomyces elongisporus clade. Three strains (KU-Xs13(T), KU-Xs18 and KU-Xs20) were assigned as a single novel species, which was named Candida saraburiensis sp. nov. The type strain is KU-Xs13(T) (=CBS 11696(T)=NBRC 106721(T)=BCC 39601(T)). Strain WB15(T) represented another novel species of the genus Candida that was named Candida prachuapensis sp. nov. The type strain is WB15(T) (=CBS 11024(T)=NBRC 104881(T)=BCC 29904(T)).

Isolation and expression of a gene (CGR1) regulated during the yeast-hyphal transition in Candida albicans.

PubMed

Cho, T; Sudoh, M; Tanaka, T; Nakashima, Y; Chibana, H; Kaminishi, H

2001-01-26

We used RNA fingerprinting of arbitrarily primed PCR to isolate genes upregulated during the yeast-hyphal transition in Candida albicans. The sequence and expression of one of these genes (CGR1, Candida growth regulation) are presented. Our results suggest that CGR1 expression is associated with a growth cessation of yeast cells, a prerequisite for germination in this organism.

Overcoming the heterologous bias: an in vivo functional analysis of multidrug efflux transporter, CgCdr1p in matched pair clinical isolates of Candida glabrata.

PubMed

Puri, Nidhi; Manoharlal, Raman; Sharma, Monika; Sanglard, Dominique; Prasad, Rajendra

2011-01-07

We have taken advantage of the natural milieu of matched pair of azole sensitive (AS) and azole resistant (AR) clinical isolates of Candida glabrata for expressing its major ABC multidrug transporter, CgCdr1p for structure and functional analysis. This was accomplished by tagging a green fluorescent protein (GFP) downstream of ORF of CgCDR1 and integrating the resultant fusion protein at its native chromosomal locus in AS and AR backgrounds. The characterization confirmed that in comparison to AS isolate, CgCdr1p-GFP was over-expressed in AR isolates due to its hyperactive native promoter and the GFP tag did not affect its functionality in either construct. We observed that in addition to Rhodamine 6 G (R6G) and Fluconazole (FLC), a recently identified fluorescent substrate of multidrug transporters Nile Red (NR) could also be expelled by CgCdr1p. Competition assays with these substrates revealed the presence of overlapping multiple drug binding sites in CgCdr1p. Point mutations employing site directed mutagenesis confirmed that the role played by unique amino acid residues critical to ATP catalysis and localization of ABC drug transporter proteins are well conserved in C. glabrata as in other yeasts. This study demonstrates a first in vivo novel system where over-expression of GFP tagged MDR transporter protein can be driven by its own hyperactive promoter of AR isolates. Taken together, this in vivo system can be exploited for the structure and functional analysis of CgCdr1p and similar proteins wherein the artefactual concerns encountered in using heterologous systems are totally excluded. Copyright © 2010 Elsevier Inc. All rights reserved.

Dynamics of Mixed- Candida Species Biofilms in Response to Antifungals.

PubMed

Vipulanandan, G; Herrera, M; Wiederhold, N P; Li, X; Mintz, J; Wickes, B L; Kadosh, D

2018-01-01

Oral infections caused by Candida species, the most commonly isolated human fungal pathogen, are frequently associated with biofilms. Although Candida albicans is the predominant organism found in patients with oral thrush, a biofilm infection, there is an increasing incidence of oral colonization and infections caused by non- albicans Candida species, including C. glabrata, C. dubliniensis, and C. tropicalis, which are frequently more resistant to antifungal treatment. While single-species Candida biofilms have been well studied, considerably less is known about the dynamics of mixed- Candida species biofilms and how these dynamics are altered by antifungal treatment. To address these questions, we developed a quantitative polymerase chain reaction-based approach to determine the precise species composition of mixed- Candida species biofilms formed by clinical isolates and laboratory strains in the presence and absence of clinically relevant concentrations of 3 commonly used antifungals: fluconazole, caspofungin, and amphotericin B. In monospecies biofilms, fluconazole exposure favored growth of C. glabrata and C. tropicalis, while caspofungin generally favored significant growth of all species to a varying degree. Fluconazole was not effective against preformed mixed- Candida species biofilms while amphotericin B was potent. As a general trend, in mixed- Candida species biofilms, C. albicans lost dominance in the presence of antifungals. Interestingly, presence in mixed versus monospecies biofilms reduced susceptibility to amphotericin B for C. tropicalis and C. glabrata. Overall, our data suggest that antifungal treatment favors the growth of specific non- albicans Candida species in mixed- Candida species biofilms.

Candida chanthaburiensis sp. nov., Candida kungkrabaensis sp. nov. and Candida suratensis sp. nov., three novel yeast species from decaying plant materials submerged in water of mangrove forests.

PubMed

Limtong, Savitree; Yongmanitchai, Wichien

2010-10-01

In a taxonomic study of yeasts isolated from decaying plant materials submerged in water of mangrove forests in Thailand, three strains isolated from tree bark (EM33(T)), a fallen leaf (EM40(T)) and a detached branch (SM56(T)) were found to represent three novel yeast species. On the basis of morphological, biochemical, physiological and chemotaxonomic characteristics, the sequence analysis of the D1/D2 domain of the large subunit (LSU) rRNA gene, and the phylogenetic analysis, the three strains were assigned as three novel Candida species. They were named as Candida chanthaburiensis sp. nov. (type strain EM33(T) = BCC 23057(T) = NBRC 102176(T) = CBS 10926(T)), Candida kungkrabaensis sp. nov. (type strain EM40(T) = BCC 23060(T) = NBRC 102179(T) = CBS 10927(T)), and Candida suratensis sp. nov. (type strain SM56(T) = BCC 25961(T) = NBRC 103858(T) = CBS 10928(T)).

Candida albicans and non-albicans species as etiological agent of vaginitis in pregnant and non-pregnant women.

PubMed

Babic, Mirela; Hukic, Mirsada

2010-02-01

Pregnancy represents a risk factor in the occurrence of vaginal candidosis. The objectives of our study were: to make determination of the microscopic findings of vaginal swab, frequency of Candida species in the culture of pregnant women and patients who are not pregnant, determine the Candida species in all cultures, and to determine the frequency and differences in the frequency of C. albicans and other non-albicans species. In one year study performed during 2006 year, we tested patients of Gynaecology and Obstetrics clinic of the Clinical Centre in Sarajevo and Gynaecology department of the General hospital in Sarajevo. 447 woman included in the study were separated in two groups: 203 pregnant (in the last trimester of pregnancy), and 244 non-pregnant woman in period of fertility. Each vaginal swab was examined microscopically. The yeast, number of colonies, and the species of Candida were determined on Sabouraud dextrose agar with presence of antibiotics. For determination of Candida species, we used germ tube test for detection of C. albicans, and cultivation on the selective medium and assimilation tests for detection of non-albicans species. The results indicated positive microscopic findings in the test group (40,9%), as well as greater number of positive cultures (46,8%). The most commonly detected species for both groups was C. albicans ( test group 40.9% and control group 23,0%). The most commonly detected non-albicans species for the test group were C. glabrata (4,2 %) and C. krusei (3,2%), and for the control group were C. glabrata (3,2%) and C. parapsilosis (3,2%). The microscopic findings correlated with the number of colonies in positive cultures. In the test group, we found an increased number of yeasts (64,3%), and the pseudopyphae and blastopores by microscopic examination as an indication of infection. In the control group, we found a small number of yeasts (64,6%) , in the form of blastopores, as an indication of the candida colonisation. Our

Use of Candida-specific chicken egg yolk antibodies to inhibit the adhering of Candida to denture base materials: prevention of denture stomatitis.

PubMed

Kamikawa, Yoshiaki; Fujisaki, Junichi; Nagayama, Tomohiro; Kawasaki, Kiyotsugu; Hirabayashi, Daisuke; Hamada, Tomofumi; Sakamoto, Ryoich; Mukai, Hiroshi; Sugihara, Kazumasa

2016-09-01

Polyclonal anti-Candida chicken egg yolk antibodies (anti-IgY) were used to investigate the prevention of adherence of Candida species to denture base material in vitro. Candida is a potential virulence factor that can cause systemic infection and even death in immunocompromised individuals. Because long-term antifungal treatment may lead to the emergence of drug-resistant strains, it is necessary to develop novel preventive measures and treatments for candidiasis. Three types of chicken egg yolk antibodies were used in this study: non-specific antibody (control IgY), Candida albicans-specific antibody (anti-C.a.IgY) and Candida glabrata-specific antibody (anti-C.g.IgY). A mixture of different dilutions of each antibody with a suspension of Candida species and denture base material was incubated for 3 h, and then the colony-forming units of Candida on the denture base material were counted. Compared with control IgY, anti-C.a.IgY and anti-C.g.IgY significantly inhibited the adherence of C. albicans, but anti-C.a.IgY tended to be more potent than anti-C.g.IgY. The adherence of C. glabrata was also inhibited significantly by anti-C.a.IgY and anti-C.g.IgY with almost equivalent potency, indicating that their actions against C. glabrata were comparable. This study revealed the inhibitory effects of anti-C.a.IgY and anti-C.g.IgY against the adherence of C. albicans and C. glabrata to denture base material. This finding indicates the possibility of a beneficial effect of IgYs for the prevention of denture stomatitis and candidiasis in clinical settings. © 2014 John Wiley & Sons A/S and The Gerodontology Association. Published by John Wiley & Sons Ltd.

De Novo Assembly of Candida sojae and Candida boidinii Genomes, Unexplored Xylose-Consuming Yeasts with Potential for Renewable Biochemical Production.

PubMed

Borelli, Guilherme; José, Juliana; Teixeira, Paulo José Pereira Lima; Dos Santos, Leandro Vieira; Pereira, Gonçalo Amarante Guimarães

2016-01-14

Candida boidinii and Candida sojae yeasts were isolated from energy cane bagasse and plague-insects. Both have fast xylose uptake rate and produce great amounts of xylitol, which are interesting features for food and 2G ethanol industries. Because they lack published genomes, we have sequenced and assembled them, offering new possibilities for gene prospection. Copyright © 2016 Borelli et al.

Synergistic mutual potentiation of antifungal activity of Zuccagnia punctata Cav. and Larrea nitida Cav. extracts in clinical isolates of Candida albicans and Candida glabrata.

PubMed

Butassi, Estefanía; Svetaz, Laura A; Ivancovich, Juan J; Feresin, Gabriela E; Tapia, Alejandro; Zacchino, Susana A

2015-06-01

Zuccagnia punctata Cav. (Fabaceae) and Larrea nitida Cav. (Zygophyllaceae) are indistinctly or jointly used in traditional medicine for the treatment of fungal-related infections. Although their dichloromethane (DCM) extract have demonstrated moderate antifungal activities when tested on their own, antifungal properties of combinations of both plants have not been assessed previously. The aim of this study was to establish with statistical rigor whether Z. punctata (ZpE) and L. nitida DCM extract (LnE) interact synergistically against the clinically important fungi Candida albicans and Candida glabrata and to characterize the most synergistic combinations. For synergism assessment, the statistical-based Boik's design was applied. Eight ZpE-LnE fixed-ratio mixtures were prepared from four different months of 1 year and tested against Candida strains. Lϕ (Loewe index) of each mixture at different fractions affected (ϕ) allowed for the finding of the most synergistic combinations, which were characterized by HPLC fingerprint and by the quantitation of the selected marker compounds. Lϕ and confidence intervals were determined in vitro with the MixLow method, once the estimated parameters from the dose-response curves of independent extracts and mixtures, were obtained. Markers (four flavonoids for ZpE and three lignans for LnE) were quantified in each extract and their combinations, with a valid HPLC-UV method. The 3D-HPLC profiles of the most synergistic mixtures were obtained by HPLC-DAD. Three over four IC50ZpE/IC50LnE fixed-ratio mixtures displayed synergistic interactions at effect levels ϕ > 0.5 against C. albicans. The dosis of the most synergistic (Lϕ = 0.62) mixture was 65.96 µg/ml (ZpE = 28%; LnE = 72%) containing 8 and 36% of flavonoids and lignans respectively. On the other hand, one over four IC50ZpE/IC50LnE mixtures displays synergistic interactions at ϕ > 0.5 against C. glabrata. The dosis of the most synergistic (Lϕ = 0.67) mixture was 168

Species spectrum and antifungal susceptibility profile of vaginal isolates of Candida in Kuwait.

PubMed

Alfouzan, W; Dhar, R; Ashkanani, H; Gupta, M; Rachel, C; Khan, Z U

2015-03-01

The study was undertaken to determine the prevalence of vulvovaginal candidiasis (VVC) among patients with vaginitis, frequency of different Candida species, and their susceptibility profile. Over six months period, high vaginal swabs were cultured on Sabouraud's dextrose agar and isolates were identified by culture on CHROMagar Candida and Vitek2 yeast identification system or/and API 20C (BioMerieux, France). Antifungal susceptibility of the Candida isolates was determined by E-test against amphotericin B, flucytosine, fluconazole, voriconazole, posaconazole and caspofungin. One thousand seven hundred and fifty-two women with vaginitis were screened for the prevalence of Candida spp. Vaginal swab cultures of 231 (13.2%) women yielded Candida spp. The isolation rates of different species were as follows: Candida albicans (73.9%), Candida glabrata (19.8%), Candida kefir (1.94%), Candida tropicalis (0.96%), Candida parapsilosis (0.96%), Candida krusei (0.96%), Candida guilliermondii (0.96%), and Saccharomyces cerevisiae (0.52%). All strains of C. albicans and non-C. albicans were susceptible to most of the antifungal agents tested. The high frequency with which C. albicans was recovered and its azole susceptibility support the continued use of azole agents for empirical therapy of uncomplicated VVC. However, a larger controlled study is required to determine the role of non-C. albicans in recurrent VVC. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

International Surveillance of Bloodstream Infections Due to Candida Species: Frequency of Occurrence and In Vitro Susceptibilities to Fluconazole, Ravuconazole, and Voriconazole of Isolates Collected from 1997 through 1999 in the SENTRY Antimicrobial Surveillance Program

PubMed Central

Pfaller, M. A.; Diekema, D. J.; Jones, R. N.; Sader, H. S.; Fluit, A. C.; Hollis, R. J.; Messer, S. A.

2001-01-01

A surveillance program (SENTRY) of bloodstream infections (BSI) in the United States, Canada, Latin America, and Europe from 1997 through 1999 detected 1,184 episodes of candidemia in 71 medical centers (32 in the United States, 23 in Europe, 9 in Latin America, and 7 in Canada). Overall, 55% of the yeast BSIs were due to Candida albicans, followed by Candida glabrata and Candida parapsilosis (15%), Candida tropicalis (9%), and miscellaneous Candida spp. (6%). In the United States, 45% of candidemias were due to non-C. albicans species. C. glabrata (21%) was the most common non-C. albicans species in the United States, and the proportion of non-C. albicans BSIs was highest in Latin America (55%). C. albicans accounted for 60% of BSI in Canada and 58% in Europe. C. parapsilosis was the most common non-C. albicans species in Latin America (25%), Canada (16%), and Europe (17%). Isolates of C. albicans, C. parapsilosis, and C. tropicalis were all highly susceptible to fluconazole (97 to 100% at ≤8 μg/ml). Likewise, 97 to 100% of these species were inhibited by ≤1 μg/ml of ravuconazole (concentration at which 50% were inhibited [MIC50], 0.007 to 0.03 μg/ml) or voriconazole (MIC50, 0.007 to 0.06 μg/ml). Both ravuconazole and voriconazole were significantly more active than fluconazole against C. glabrata (MIC90s of 0.5 to 1.0 μg/ml versus 16 to 32 μg/ml, respectively). A trend of increased susceptibility of C. glabrata to fluconazole was noted over the three-year period. The percentage of C. glabrata isolates susceptible to fluconazole increased from 48% in 1997 to 84% in 1999, and MIC50s decreased from 16 to 4 μg/ml. A similar trend was documented in both the Americas (57 to 84% susceptible) and Europe (22 to 80% susceptible). Some geographic differences in susceptibility to triazole were observed with Canadian isolates generally more susceptible than isolates from the United States and Europe. These observations suggest susceptibility patterns and trends

Rare opportunistic (non-Candida, non-Cryptococcus) Yeast Bloodstream Infections in Patients with Cancer

PubMed Central

Chitasombat, Maria N.; Kofteridis, Diamantis P.; Jiang, Ying; Tarrand, Jeffrey; Lewis, Russell E.; Kontoyiannis, Dimitrios P.

2013-01-01

Background Rare opportunistic (non-Candida, non-Cryptococcus) yeast bloodstream infections (ROYBSIs) are rare, even in cancer patients. Methods We retrospectively reviewed all episodes of ROYBSIs occurring from 1998 to 2010 in our cancer center. Results Of 2984 blood cultures positive for Candida and non-Candida yeasts, 94 (3.1%) were positive for non-Candida yeasts, representing 41 ROYBSIs (incidence, 2.1 cases/100,000 patient-days). Catheter-associated fungemia occurred in 21 (51%) patients. Breakthrough ROYBSIs occurred in 20 (49%) patients. The yeast species distribution was Rhodotorula in 21 (51%) patients, Trichosporon in 8 (20%) patients, Saccharomyces cerevisiae in 8 (20%) patients, Geotrichum in 2 (5%) patients, Pichia anomala, and Malassezia furfur in 1 patient each. All tested Trichosporon, Geotrichum, and Pichia isolates were azole-susceptible, whereas the Rhodotorula isolates were mostly azole-resistant. We noted echinocandin nonsusceptibility (minimal inhibitory concentration ≥ 2 mg/L) in all but the S. cerevisiae isolates. Most of the isolates (28/33 [85%]) were susceptible to amphotericin B. The mortality rate in all patients at 30 days after ROYBSIs diagnosis was 34%. Multivariate survival analysis revealed increased risk of death in patients with S. cerevisiae infections (hazard ratio, 3.7), Geotrichum infections (hazard ratio, 111.3), or disseminated infections (hazard ratio, 33.4) and reduced risk in patients who had catheter removal (hazard ratio, 0.1). Conclusions ROYBSIs are uncommon in patients with cancer, and catheters are common sources of them. Half of the ROYBSIs occurred as breakthrough infections, and in vitro species-specific resistance to echinocandins and azoles was common. Disseminated infections resulted in the high mortality rate. PMID:22101079

[Comparison of methods for the identification of the most common yeasts in the clinical microbiology laboratory].

PubMed

Guelfand, L; Grisolía, P; Bozzano, C; Kaufman, S

2003-01-01

We evaluated different methods for the routine identification of medically important yeasts. A total of 150 clinical isolates: 25 C. albicans, 25 C. tropicalis, 25 C. glabrata, 25 C. parapsilosis, 8 C. guilliermondii, 11 C. krusei and 31 Cryptococcus neoformans were tested by Yeast Biochemical Card bioMerieux Vitek (YBC), CHROMagar Candida (CHR). The addition of yeast morphology in Corn Meal agar-Tween 80 (AM) to YBC and CHR was also evaluated. The reference methods used were: API 20C, germ tube formation, AM, Christensen urea and Birdseed agar. YBC identified 135 yeasts with an overall accuracy of 90%. Sensitivity (S) and specificity (E) were: 92-98% for C. albicans and C. tropicalis; 84-99% for C. papapsilosis; 100-99% for C. glabrata; 91-100% for C. krusei; 63-98% for C. guilliermondii and 90-99% for Cryptococcus neoformans, respectively. CHR identified correctly 100% for C. albicans, 92% for C. tropicalis and 91% for C. krusei. Both methods combined with AM provided 100% S and E. We found that YBC system was appropriate for identification of yeasts isolated from human sources. CHR was effective and easy to use for identification of C. albicans, C. tropicalis and C. krusei. The routine use of AM with both methods is recommended.

Prevalence of Candida co-infection in patients with pulmonary tuberculosis.

PubMed

Kali, Arunava; Charles, Mv Pravin; Noyal, Mariya Joseph; Sivaraman, Umadevi; Kumar, Shailesh; Easow, Joshy M

2013-01-01

Candida species are emerging as a potentially pathogenic fungus in patients with broncho-pulmonary diseases. The synergistic growth promoting association of Candida and Mycobacterium tuberculosis has raised increased concern for studying the various Candida spp . and its significance in pulmonary tuberculosis patients during current years. This study was undertaken with the objective of discovering the prevalence of co-infection caused by different Candida species in patients with pulmonary tuberculosis. A total of 75 patients with pulmonary tuberculosis diagnosed by sputum Ziehl-Neelsen staining were included in the study. Candida co-infection was confirmed using the Kahanpaa et al. criteria. Candida species were identified using gram stain morphology, germ tube formation, morphology on cornmeal agar with Tween-80, sugar fermentation tests and HiCrome Candida Agar. Candida co-infection was observed in 30 (40%) of patients with pulmonary tuberculosis. Candida albicans was the most common isolate observed in 50% of the patients with co-infection, followed by C. tropicalis (20%) and C. glabrata (20%). Candida co-infection was found in 62.5% of female patients, while it was observed in only 29.4% of the male patients (P value 0.0133). Mean ± SD age of the patients with C. glabrata infection was 65.83 ± 3.19, while the mean ± SD age of the patients with other Candida infections was 43.25 ± 20.44 (P value 0.0138). Many patients with pulmonary tuberculosis have co-infection with Candida spp. The prevalence of non-albicans Candida species is increasing and may be associated with inadequate response to anti-tubercular drugs. C. glabrata infection has a strong association with old age.

Probiotic Lactobacillus reuteri has antifungal effects on oral Candida species in vitro

PubMed Central

Jørgensen, Mette Rose; Kragelund, Camilla; Jensen, Peter Østrup; Keller, Mette Kirstine; Twetman, Svante

2017-01-01

ABSTRACT Background: An alternative approach for managing Candida infections in the oral cavity by modulating the oral microbiota with probiotic bacteria has been proposed. Objective: The aim was to investigate the antifungal potential of the probiotic bacterium Lactobacillus reuteri (DSM 17938 and ATCC PTA 5289) against six oral Candida species (C. albicans, C. glabrata, C. krusei, C. tropicalis, C. dubliniensis, and C. parapsilosis). Design: The lactobacilli were tested for their ability to co-aggregate with and inhibit the growth of the yeasts assessed by spectrophotometry and the agar overlay inhibition assay. Additionally, the pH was evaluated with microsensors, and the production of hydrogen peroxide (H2O2) by the lactobacilli was verified. Results: Both L. reuteri strains showed co-aggregation abilities with the yeasts. The lactobacilli almost completely inhibited the growth of C. albicans and C. parapsilosis, but did not affect C. krusei. Statistically significant differences in co-aggregation and growth inhibition capacities between the two L. reuteri strains were observed (p<0.001). The pH measurements suggested that C. krusei can resist the acids produced by the lactobacilli. Conclusions: L. reuteri exhibited antifungal properties against five of the six most common oral Candida species. Further, the results reconfirms that the probiotic capacity of L. reuteri is strain specific. PMID:28326154

Five novel Wickerhamomyces- and Metschnikowia-related yeast species, Wickerhamomyces chaumierensis sp. nov., Candida pseudoflosculorum sp. nov., Candida danieliae sp. nov., Candida robnettiae sp. nov. and Candida eppingiae sp. nov., isolated from plants.

PubMed

Groenewald, Marizeth; Robert, Vincent; Smith, Maudy Th

2011-08-01

On the basis of nucleotide divergences in the D1/D2 domain of the 26S rRNA gene and the internal transcribed spacers (ITS) domain of the rRNA gene, five novel yeast species, Wickerhamomyces chaumierensis sp. nov. (CBS 8565(T)  = JCM 17246(T)), Candida pseudoflosculorum sp. nov. (CBS 8584(T)  = JCM 17242(T)), Candida danieliae sp. nov. (CBS 8533(T)  = JCM 17247(T)), Candida robnettiae sp. nov. (CBS 8580(T)  = JCM 17243(T)) and Candida eppingiae sp. nov. (CBS 8586(T)  = JCM 17241(T)), isolated from plants in Thailand and Guyana, are proposed in this study.

Candida baotianmanensis sp. nov. and Candida pseudoviswanathii sp. nov., two ascosporic yeast species isolated from the gut of beetles.

PubMed

Ren, Yong-Cheng; Xu, Long-Long; Zhang, Lin; Hui, Feng-Li

2015-10-01

Four yeast strains were isolated from the gut of beetles collected on Baotianman Mountain and People's Park of Nanyang in Henan Province, China. These strains produced unconjugated asci with one or two ellipsoidal to elongate ascospores in a persistent ascus. Phylogenetic analysis of the D1/D2 domains of the LSU rRNA gene sequences indicated that the isolates represent two novel sexual species in the Candida/Lodderomyces clade. Candida baotianmanensis sp. nov. was located in a statistically well-supported branch together with Candida maltosa. Candida pseudoviswanathii sp. nov. formed a subclade with its closest relative Candida viswanathii supported by a strong bootstrap value. The two novel species were distinguished from their most closely related described species, Candida maltosa and Candida viswanathii, in the D1/D2 LSU rRNA gene and internal transcribed spacer (ITS) sequences and in phenotypic traits. The type strain of Candida baotianmanensis sp. nov. is NYNU 14719T ( = CBS 13915T = CICC 33052T), and the type strain of Candida pseudoviswanathii sp. nov. is NYNU 14772T ( = CBS 13916T = CICC 33053T). The MycoBank numbers for Candida baotianmanensis sp. nov. and Candida pseudoviswanathii sp. nov. are MB 812621 and MB 812622.

Multicenter Study Evaluating the Vitek MS System for Identification of Medically Important Yeasts

PubMed Central

Westblade, Lars F.; Jennemann, Rebecca; Branda, John A.; Bythrow, Maureen; Ferraro, Mary Jane; Garner, Omai B.; Ginocchio, Christine C.; Lewinski, Michael A.; Manji, Ryhana; Mochon, A. Brian; Procop, Gary W.; Richter, Sandra S.; Rychert, Jenna A.; Sercia, Linda

2013-01-01

The optimal management of fungal infections is correlated with timely organism identification. Matrix-assisted laser desorption ionization–time of flight (MALDI-TOF) mass spectrometry (MS) is revolutionizing the identification of yeasts isolated from clinical specimens. We present a multicenter study assessing the performance of the Vitek MS system (bioMérieux) in identifying medically important yeasts. A collection of 852 isolates was tested, including 20 Candida species (626 isolates, including 58 C. albicans, 62 C. glabrata, and 53 C. krusei isolates), 35 Cryptococcus neoformans isolates, and 191 other clinically relevant yeast isolates; in total, 31 different species were evaluated. Isolates were directly applied to a target plate, followed by a formic acid overlay. Mass spectra were acquired using the Vitek MS system and were analyzed using the Vitek MS v2.0 database. The gold standard for identification was sequence analysis of the D2 region of the 26S rRNA gene. In total, 823 isolates (96.6%) were identified to the genus level and 819 isolates (96.1%) were identified to the species level. Twenty-four isolates (2.8%) were not identified, and five isolates (0.6%) were misidentified. Misidentified isolates included one isolate of C. albicans (n = 58) identified as Candida dubliniensis, one isolate of Candida parapsilosis (n = 73) identified as Candida pelliculosa, and three isolates of Geotrichum klebahnii (n = 6) identified as Geotrichum candidum. The identification of clinically relevant yeasts using MS is superior to the phenotypic identification systems currently employed in clinical microbiology laboratories. PMID:23658267

Multicenter study evaluating the Vitek MS system for identification of medically important yeasts.

PubMed

Westblade, Lars F; Jennemann, Rebecca; Branda, John A; Bythrow, Maureen; Ferraro, Mary Jane; Garner, Omai B; Ginocchio, Christine C; Lewinski, Michael A; Manji, Ryhana; Mochon, A Brian; Procop, Gary W; Richter, Sandra S; Rychert, Jenna A; Sercia, Linda; Burnham, Carey-Ann D

2013-07-01

The optimal management of fungal infections is correlated with timely organism identification. Matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry (MS) is revolutionizing the identification of yeasts isolated from clinical specimens. We present a multicenter study assessing the performance of the Vitek MS system (bioMérieux) in identifying medically important yeasts. A collection of 852 isolates was tested, including 20 Candida species (626 isolates, including 58 C. albicans, 62 C. glabrata, and 53 C. krusei isolates), 35 Cryptococcus neoformans isolates, and 191 other clinically relevant yeast isolates; in total, 31 different species were evaluated. Isolates were directly applied to a target plate, followed by a formic acid overlay. Mass spectra were acquired using the Vitek MS system and were analyzed using the Vitek MS v2.0 database. The gold standard for identification was sequence analysis of the D2 region of the 26S rRNA gene. In total, 823 isolates (96.6%) were identified to the genus level and 819 isolates (96.1%) were identified to the species level. Twenty-four isolates (2.8%) were not identified, and five isolates (0.6%) were misidentified. Misidentified isolates included one isolate of C. albicans (n = 58) identified as Candida dubliniensis, one isolate of Candida parapsilosis (n = 73) identified as Candida pelliculosa, and three isolates of Geotrichum klebahnii (n = 6) identified as Geotrichum candidum. The identification of clinically relevant yeasts using MS is superior to the phenotypic identification systems currently employed in clinical microbiology laboratories.

Candida queiroziae sp. nov., a cellobiose-fermenting yeast species isolated from rotting wood in Atlantic Rain Forest.

PubMed

Santos, Renata O; Cadete, Raquel M; Badotti, Fernanda; Mouro, Adriane; Wallheim, Daniela O; Gomes, Fátima C O; Stambuk, Boris U; Lachance, Marc-André; Rosa, Carlos A

2011-03-01

Eight strains of a novel yeast species were isolated from rotting wood and wood-boring insects in Atlantic Rain Forest ecosystems in Brazil. Sequences of the D1/D2 domains of the large subunit of the rRNA gene showed that the yeast belongs to the Scheffersomyces clade and that it is related to Candida lignicola and Candida coipomoensis. The new species was isolated from rotting wood of three different localities and a wood-boring insect suggesting that these substrates are its ecological niche. This new yeast species is able to assimilate cellobiose and other compounds related to rotting wood. Strong fermentation of cellobiose in Durham tubes was observed for the strains of this new yeast. The new species produced an intracellular β-glucosidase responsible for cellobiose hydrolysis. The novel species, Candida queiroziae sp. nov., is proposed to accommodate these isolates. The type strain of C. queiroziae is UFMG-CLM 5.1(T) (=CBS 11853(T) = NRRL Y-48722(T)).

Molecular characterization of Candida isolates from intensive care unit patients, Krakow, Poland.

PubMed

Małek, Marianna; Paluchowska, Paulina; Bogusz, Bożena; Budak, Alicja

Over the last decades, Candida species have emerged as important pathogens in immunocompromised patients. Nosocomial infections are mainly of endogenous origin. Nevertheless, some cases of exogenous candidiasis have also been reported. The aim of this study was to evaluate the genetic relatedness between Candida albicans, Candida glabrata, Candida tropicalis, Candida krusei and Candida kefyr isolates recovered from intensive care unit (ICU) patients. A total of 132 Candida clinical isolates (62 C. albicans, 40 C. glabrata, 13 C. tropicalis, 11 C. krusei, 6 C. kefyr), obtained from specimens of endotracheal aspirate, urine and blood taken from patients of a tertiary hospital in Poland, were included in the study. Species identification was performed by PCR method and genetic relatedness was assessed by randomly amplified polymorphic DNA assay (RAPD) with five primers. The RAPD analysis revealed high genetic diversity among the studied Candida isolates, indicating that most of the strains were from endogenous sources. Only two clonal strains of C. glabrata isolated from different patients were observed, suggesting a possible cross-transmission of these pathogens. Our study confirmed the high discriminatory power of the RAPD assay. This genotyping method can be applied to local epidemiological studies of Candida species. Copyright © 2016 Asociación Española de Micología. Publicado por Elsevier España, S.L.U. All rights reserved.

Occurrence of yeasts in psittacines droppings from captive birds in Italy.

PubMed

Mancianti, Francesca; Nardoni, Simona; Ceccherelli, Renato

2002-01-01

Three-hundred twenty five droppings from parrots raised in the premises of 4 breeders and in several private households were cultured for yeasts. One-hundred sixty droppings (49.2%) resulted positive. From these specimens 212 isolates belonging to 27 different species were obtained. Mainly Candida species such as C. albicans, C. catenulata, C. curvata, C. famata, C. glabrata, C. guilliermondi, C. holmii, C. intermedia, C. krusei, C. lambica, C. lusitaniae, C. membranaefaciens, C. parapsilosis, C. pelliculosa, C. sake and C. valida were isolated. Debarvomyces marama, D. polymorphus, Geotrichum sp., Pichia etchelsii, P. ohmeri, Rhodotorula glutinis, R. rubra, Rhodotorula sp., Saccharomyces cerevisiae, S. kluyiveri and Zygosaccharomyces sp. were also obtained. Dark colonies on Staib medium were never observed. The psittacine birds apparently serve as carriers for several Candida species or their perfect states and to a lesser extent for other opportunistic yeasts such as Rhodotorula, Trichosporon and Saccharomyces spp., which are considered part of the transient microbiota of the gastrointestinal tract. The most striking finding was the absence of Cryptococcus spp. among the isolates. The present survey confirms the role of pet birds in carrying potential zoonotic yeasts.

[Yeast urinary tract infections. Multicentre study in 14 hospitals belonging to the Buenos Aires City Mycology Network].

PubMed

Maldonado, Ivana; Arechavala, Alicia; Guelfand, Liliana; Relloso, Silvia; Garbasz, Claudia

2016-01-01

Urinary tract infections are a frequent ailment in patients in intensive care units. Candida and other yeasts cause 5-12% of these infections. The value of the finding of any yeast is controversial, and there is no consensus about which parameters are adequate for differentiating urinary infections from colonization or contamination. To analyse the epidemiological characteristics of patients with funguria, to determine potential cut-off points in cultures (to distinguish an infection from other conditions), to identify the prevalent yeast species, and to determine the value of a second urine sample. A multicentre study was conducted in intensive care units of 14 hospitals in the Buenos Aires City Mycology Network. The first and second samples of urine from every patient were cultured. The presence of white cells and yeasts in direct examination, colony counts, and the identification of the isolated species, were evaluated. Yeasts grew in 12.2% of the samples. There was no statistical correlation between the number of white cells and the fungal colony-forming units. Eighty five percent of the patients had indwelling catheters. Funguria was not prevalent in women or in patients over the age of 65. Candida albicans, followed by Candida tropicalis, were the most frequently isolated yeasts. Candida parapsilosis and Candida glabrata appeared less frequently. The same species were isolated in 70% of second samples, and in 23% of the cases the second culture was negative. It was not possible to determine a useful cut-off point for colony counts to help in the diagnosis of urinary infections. As in other publications, C. albicans, followed by C. tropicalis, were the most prevalent species. Copyright © 2015 Asociación Española de Micología. Published by Elsevier Espana. All rights reserved.

Molecular Identification and Antifungal Susceptibility Pattern of Non-albicans Candida Species Isolated from Vulvovaginal Candidiasis

PubMed Central

Nejat, Ziba Abbasi; Farahyar, Shirin; Falahati, Mehraban; Khozani, Mahtab Ashrafi; Hosseini, Aga Fateme; Faiazy, Azamsadat; Ekhtiari, Masoome; Hashemi-Hafshenjani, Saeideh

2018-01-01

Background: Vulvovaginal candidiasis (VVC) is an important health problem caused by Candida spp. The aim of this study was molecular identification, phylogenetic analysis, and evaluation of antifungal susceptibility of non-albicans Candida isolates from VVC. Methods: Vaginal secretion samples were collected from 550 vaginitis patients at Sayyad Shirazi Medical and Educational Center of Gorgan (Golestan Province, Iran) from May to October 2015. Samples were analyzed using conventional mycological and molecular approaches. Clinical isolates were analyzed with specific PCR using CGL primers, and the internal transcribed spacer region and the D1-D2 domain of the large-subunit rRNA gene were amplified and sequenced. Susceptibility to amphotericin B, fluconazole, itraconazole, and clotrimazole was determined by the guidelines of the Clinical and Laboratory Standard Institute. Results: In total, 35 non-albicans Candida isolates were identified from VVC patients. The isolates included 27 strains of Candida glabrata (77.1%), 5 Candida krusei (Pichia kudriavzevii; 14.3%), 2 Candida kefyr (Kluyveromyces marxianus; 5.7%), and 1 Candida lusitaniae (Clavispora lusitaniae; 2.9%). The fungicides itraconazole and amphotericin B were effective against all species. One isolate of C. glabrata showed resistance to fluconazole and clotrimazole, and 26 isolates of C. glabrata indicated dose-dependent susceptibility to fluconazole. C. lusitaniae was susceptible in a dose-dependent manner to fluconazole and resistant to clotrimazole. Conclusions: Non-albicans Candida spp. are common agents of vulvovaginitis, and C. glabrata is the most common species in the tested patients. PMID:28688376

KRE5 Suppression Induces Cell Wall Stress and Alternative ER Stress Response Required for Maintaining Cell Wall Integrity in Candida glabrata

PubMed Central

Sasaki, Masato; Ito, Fumie; Aoyama, Toshio; Sato-Okamoto, Michiyo; Takahashi-Nakaguchi, Azusa; Chibana, Hiroji; Shibata, Nobuyuki

2016-01-01

The maintenance of cell wall integrity in fungi is required for normal cell growth, division, hyphae formation, and antifungal tolerance. We observed that endoplasmic reticulum stress regulated cell wall integrity in Candida glabrata, which possesses uniquely evolved mechanisms for unfolded protein response mechanisms. Tetracycline-mediated suppression of KRE5, which encodes a predicted UDP-glucose:glycoprotein glucosyltransferase localized in the endoplasmic reticulum, significantly increased cell wall chitin content and decreased cell wall β-1,6-glucan content. KRE5 repression induced endoplasmic reticulum stress-related gene expression and MAP kinase pathway activation, including Slt2p and Hog1p phosphorylation, through the cell wall integrity signaling pathway. Moreover, the calcineurin pathway negatively regulated cell wall integrity, but not the reduction of β-1,6-glucan content. These results indicate that KRE5 is required for maintaining both endoplasmic reticulum homeostasis and cell wall integrity, and that the calcineurin pathway acts as a regulator of chitin-glucan balance in the cell wall and as an alternative mediator of endoplasmic reticulum stress in C. glabrata. PMID:27548283

Gut yeast communities in Larus michahellis from various breeding colonies.

PubMed

Al-Yasiri, Mohammed Hashim; Normand, Anne-Cécile; Piarroux, Renaud; Ranque, Stéphane; Mauffrey, Jean-François

2017-06-01

Yellow-legged gulls have been reported to carry antibiotic-resistant Enterobacteriaceae; however, the gut mycobiota of these birds has not yet been described. In this study, we analyzed the gut yeast communities in five yellow-legged gull breeding colonies along the Mediterranean littoral in southern France. Gull fecal samples were inoculated onto four types of culture media, including one supplemented with itraconazole. Yeast species richness, abundance, and diversity were estimated, and factorial analysis was used to highlight correspondences between breeding colonies. Yeast grew in 113 of 177 cultures, and 17 distinct yeast species were identified. The most frequent species were Candida krusei (53.5%), Galactomyces geotrichum (44.1%), C. glabrata (40.9%), C. albicans (20.5%), and Saccharomyces cerevisiae (18.1%). Gut yeast community structure in the gulls at both Pierre-Blanche Lagoon (PB) and Frioul Archipelago (F) were characterized by greater species richness and diversity than in those at the two cities of La Grande-Motte (GM) and Palavas-les-Flots (PF) as well as Riou Archipelago (R). Gulls in these latter three sites probably share a similar type of anthropogenic diet. Notably, the proportion of anthropic yeast species, including C. albicans and C. glabrata, in the gull mycobiota increased with gull colony synanthropy. Antifungal resistance was found in each of the five most frequent yeast species. We found that the gut yeast communities of these yellow-legged gulls include antifungal-resistant human pathogens. Further studies should assess the public health impact of these common synanthropic seabirds, which represent a reservoir and disseminator of drug-resistant human pathogenic yeast into the environment. © The Author 2016. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Candida davenportii sp. nov., a potential soft-drinks spoilage yeast isolated from a wasp.

PubMed

Stratford, M; Bond, C J; James, S A; Roberts, N; Steels, H

2002-07-01

During a survey of yeast ecology in a soft-drinks production facility, a dead wasp was removed from the sampling tap of an external sugar-syrup storage tank. A yeast isolated from the dead wasp was found to be similar, although not identical, in its physiological characteristics to Candida lactis-condensi and Candida stellata. Sequence analysis of the 26S rDNA D1/D2 variable domain revealed that this isolate was most closely related to C stellata, but differed sufficiently in its D1/D2 sequence to indicate that it belonged to a separate species. The yeast species has been named Candida davenportii sp. nov.; the type strain is NCYC 3013T (= CBS 9069T). C davenportii sp. nov. was osmotolerant, moderately preservative-resistant and able to grow in very acidic conditions, i.e. pH 14. This yeast grew well in fruit-containing soft drinks, cola-type beverages and a synthetic soft drink and is therefore a potential cause of spoilage of soft drinks and other sugary food products. Other related yeast species in the same taxonomic clade as C davenportii sp. nov. are also osmotolerant, growing in < 50% (w/v) sugar. Many of these species are associated with insects, specifically bees, bumblebees and leafcutter bees, and many have been reported as the causative agent of spoilage of sugary foods, such as condensed milk, fruit juices and concentrates. It is proposed that C davenportii sp. nov. and other closely related yeasts are primarily associated with Aculeates (bees and wasps). In turn, bees and wasps are attracted by sugary residues in foods such as fruit juices and concentrates, forming the source of infection of these yeasts and thus instigating spoilage.

Pseudozyma and other non-Candida opportunistic yeast bloodstream infections in a large stem cell transplant center.

PubMed

Pande, Anupam; Non, Lemuel R; Romee, Rizwan; Santos, Carlos A Q

2017-04-01

Non-Candida opportunistic yeasts are emerging causes of bloodstream infection (BSI) in immunocompromised hosts. However, their clinical presentation, management, and outcomes in stem cell transplant (SCT) recipients are not well described. We report the first case to our knowledge of Pseudozyma BSI in a SCT recipient. He had evidence of cutaneous involvement, which has not been previously described in the literature. He became infected while neutropenic and receiving empiric micafungin, which is notable because Pseudozyma is reported to be resistant to echinocandins. He was successfully treated with the sequential use of liposomal amphotericin B and voriconazole. A review of the literature revealed nine reported instances of Pseudozyma fungemia. We performed a retrospective review of 3557 SCT recipients at our institution from January 2000 to June 2015 and identified four additional cases of non-Candida yeast BSIs. These include two with Cryptococcus, one with Trichosporon, and one with Saccharomyces. Pseudozyma and other non-Candida yeasts are emerging pathogens that can cause severe and disseminated infections in SCT recipients and other immunocompromised hosts. Clinicians should have a high degree of suspicion for echinocandin-resistant yeasts, if patients develop breakthrough yeast BSIs while receiving echinocandin therapy. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Antifungal susceptibilities of Candida species isolated from the patients with vaginal candidiasis.

PubMed

Nagashima, Masahito; Yamagishi, Yuka; Mikamo, Hiroshige

2016-02-01

There have been the current Japanese data on susceptibility testing for Candida isolates from vaginal candidiasis. The in vitro activities of therapeutic antifungal drugs for vulvovaginal candidiasis (VVC); miconazole (MCZ), itraconazole (ITCZ), fluconazole (FLCZ), clotrimazole (CTZ), oxiconazole (OCZ), isoconazole (ICZ) and bifonazole (BFZ) against vaginal isolates. Fifty-four strains Candida albicans and 19 strains of Candida glabrata were evaluated using a broth microdilution method specified by Clinical Laboratories Standard Institute (CLSI) document M27-A3. The MIC90 of each drug, MCZ, ITCZ, FLCZ, CTZ, OCZ, ICZ and BFZ, against C. albicans and C. glabrata isolates were 0.25, 0.12, 1, 0.06, 0.12, 0.12 and 1 μg/ml and 1, 1, 8, 0.5, 0.25, 0.5 and 1 μg/ml respectively. The activities of these drugs, except for BFZ, against C. glabrata were lower than that of C. albicans. There was one azole-resistant isolate in C. glabrata of which MIC of FLCZ is > 64 μg/ml and this isolate had cross resistance to other antifungal drugs tested. These results suggest that antifungal drugs for treatment of VVC continues to have potent antifungal activities against C. albicans and C. glabrata isolates from vaginitis. CTZ, OCZ and ICZ susceptibility of FLCZ low susceptibility C. glabrata are relatively higher than MCZ, ITCZ and FLCZ. Copyright © 2015. Published by Elsevier Ltd.

Molecular detection of candida species from hospitalized patient’s specimens.

PubMed

Camacho-Cardoso, José Luis; Martínez-Rivera, María Ángeles; Manzano-Gayosso, Patricia; Méndez-Tovar, Luis Javier; López-Martínez, Rubén; Hernández-Hernández, Francisca

To identify the most frequent Candida species in specimens from patients hospitalized in different medical centers of Mexico City, with suspected fungal infection. Specimens were grown on Sabouraud dextrose agar at 28°C for 72 h. In addition, DNA was extracted. Isolates were grown on CHROMagar Candida™, at 37°C for 48 h. The molecular identification was performed by polymerase chain reaction (PCR) using primers specific for four species. Eighty one specimens were processed and included: bronchial lavage, pleural, cerebrospinal, peritoneal, ascites and bile fluids; blood, sputum, bone marrow, oro-tracheal cannula and ganglion. By culture, 30 samples (37%) were positive, and by PCR, 41 (50.6%). By PCR, the frequency of species was: Candida albicans 82.9%, Candida tropicalis 31.7%, Candida glabrata 24.4%, and Candida parapsilosis 4.9%. In 34.1% of specimens a species mixture was detected suggesting a co-infection: Two species in five specimens (C. albicans-C tropicalis and C. albicans-C glabrata), and three species in three specimens (C. albicans-C. glabrata-C. tropicalis). The PCR is an useful tool for detection the most common Candida species causing infection in hospitalized patients, it avoids the requirement of culture weather we start from clinical specimen and it favors the early diagnosis of invasive candidiasis. Copyright: © 2017 SecretarÍa de Salud

SNF3 as High Affinity Glucose Sensor and Its Function in Supporting the Viability of Candida glabrata under Glucose-Limited Environment.

PubMed

Ng, Tzu Shan; Chew, Shu Yih; Rangasamy, Premmala; Mohd Desa, Mohd N; Sandai, Doblin; Chong, Pei Pei; Than, Leslie Thian Lung

2015-01-01

Candida glabrata is an emerging human fungal pathogen that has efficacious nutrient sensing and responsiveness ability. It can be seen through its ability to thrive in diverse range of nutrient limited-human anatomical sites. Therefore, nutrient sensing particularly glucose sensing is thought to be crucial in contributing to the development and fitness of the pathogen. This study aimed to elucidate the role of SNF3 (Sucrose Non Fermenting 3) as a glucose sensor and its possible role in contributing to the fitness and survivability of C. glabrata in glucose-limited environment. The SNF3 knockout strain was constructed and subjected to different glucose concentrations to evaluate its growth, biofilm formation, amphotericin B susceptibility, ex vivo survivability and effects on the transcriptional profiling of the sugar receptor repressor (SRR) pathway-related genes. The CgSNF3Δ strain showed a retarded growth in low glucose environments (0.01 and 0.1%) in both fermentation and respiration-preferred conditions but grew well in high glucose concentration environments (1 and 2%). It was also found to be more susceptible to amphotericin B in low glucose environment (0.1%) and macrophage engulfment but showed no difference in the biofilm formation capability. The deletion of SNF3 also resulted in the down-regulation of about half of hexose transporters genes (four out of nine). Overall, the deletion of SNF3 causes significant reduction in the ability of C. glabrata to sense limited surrounding glucose and consequently disrupts its competency to transport and perform the uptake of this critical nutrient. This study highlighted the role of SNF3 as a high affinity glucose sensor and its role in aiding the survivability of C. glabrata particularly in glucose limited environment.

Competitive Interactions between C. albicans, C. glabrata and C. krusei during Biofilm Formation and Development of Experimental Candidiasis.

PubMed

Rossoni, Rodnei Dennis; Barbosa, Júnia Oliveira; Vilela, Simone Furgeri Godinho; dos Santos, Jéssica Diane; de Barros, Patrícia Pimentel; Prata, Márcia Cristina de Azevedo; Anbinder, Ana Lia; Fuchs, Beth Burgwyn; Jorge, Antonio Olavo Cardoso; Mylonakis, Eleftherios; Junqueira, Juliana Campos

2015-01-01

In this study, we evaluated the interactions between Candida albicans, Candida krusei and Candida glabrata in mixed infections. Initially, these interactions were studied in biofilms formed in vitro. CFU/mL values of C. albicans were lower in mixed biofilms when compared to the single biofilms, verifying 77% and 89% of C. albicans reduction when this species was associated with C. glabrata and C. krusei, respectively. After that, we expanded this study for in vivo host models of experimental candidiasis. G. mellonella larvae were inoculated with monotypic and heterotypic Candida suspensions for analysis of survival rate and quantification of fungal cells in the haemolymph. In the groups with single infections, 100% of the larvae died within 18 h after infection with C. albicans. However, interaction groups achieved 100% mortality after 72 h of infection by C. albicans-C. glabrata and 96 h of infection by C. albicans-C. krusei. C. albicans CFU/mL values from larvae hemolymph were lower in the interacting groups compared with the monoespecies group after 12 h of infection. In addition, immunosuppressed mice were also inoculated with monotypic and heterotypic microbial suspensions to induce oral candidiasis. C. albicans CFU/mL values recovered from oral cavity of mice were higher in the group with single infection by C. albicans than the groups with mixed infections by C. albicans-C. glabrata and C. albicans-C. krusei. Moreover, the group with single infection by C. albicans had a higher degree of hyphae and epithelial changes in the tongue dorsum than the groups with mixed infections. We concluded that single infections by C. albicans were more harmful for animal models than mixed infections with non-albicans species, suggesting that C. albicans establish competitive interactions with C. krusei and C. glabrata during biofilm formation and development of experimental candidiasis.

Competitive Interactions between C. albicans, C. glabrata and C. krusei during Biofilm Formation and Development of Experimental Candidiasis

PubMed Central

Rossoni, Rodnei Dennis; Barbosa, Júnia Oliveira; Vilela, Simone Furgeri Godinho; dos Santos, Jéssica Diane; de Barros, Patrícia Pimentel; Prata, Márcia Cristina de Azevedo; Anbinder, Ana Lia; Fuchs, Beth Burgwyn; Jorge, Antonio Olavo Cardoso; Mylonakis, Eleftherios; Junqueira, Juliana Campos

2015-01-01

In this study, we evaluated the interactions between Candida albicans, Candida krusei and Candida glabrata in mixed infections. Initially, these interactions were studied in biofilms formed in vitro. CFU/mL values of C. albicans were lower in mixed biofilms when compared to the single biofilms, verifying 77% and 89% of C. albicans reduction when this species was associated with C. glabrata and C. krusei, respectively. After that, we expanded this study for in vivo host models of experimental candidiasis. G. mellonella larvae were inoculated with monotypic and heterotypic Candida suspensions for analysis of survival rate and quantification of fungal cells in the haemolymph. In the groups with single infections, 100% of the larvae died within 18 h after infection with C. albicans. However, interaction groups achieved 100% mortality after 72 h of infection by C. albicans-C. glabrata and 96 h of infection by C. albicans-C. krusei. C. albicans CFU/mL values from larvae hemolymph were lower in the interacting groups compared with the monoespecies group after 12 h of infection. In addition, immunosuppressed mice were also inoculated with monotypic and heterotypic microbial suspensions to induce oral candidiasis. C. albicans CFU/mL values recovered from oral cavity of mice were higher in the group with single infection by C. albicans than the groups with mixed infections by C. albicans-C. glabrata and C. albicans-C. krusei. Moreover, the group with single infection by C. albicans had a higher degree of hyphae and epithelial changes in the tongue dorsum than the groups with mixed infections. We concluded that single infections by C. albicans were more harmful for animal models than mixed infections with non-albicans species, suggesting that C. albicans establish competitive interactions with C. krusei and C. glabrata during biofilm formation and development of experimental candidiasis. PMID:26146832

Epidemiological investigation of Candida species causing bloodstream infection in paediatric small bowel transplant recipients.

PubMed

Suhr, Mallory J; Gomes-Neto, João Carlos; Banjara, Nabaraj; Florescu, Diana F; Mercer, David F; Iwen, Peter C; Hallen-Adams, Heather E

2017-06-01

Small bowel transplantation (SBT) can be a life-saving medical procedure. However, these recipients experience high risk of bloodstream infections caused by Candida. This research aims to characterise the SBT recipient gut microbiota over time following transplantation and investigate the epidemiology of candidaemia in seven paediatric patients. Candida species from the recipients' ileum and bloodstream were identified by internal transcribed spacer sequence and distinguished to strain by multilocus sequence typing and randomly amplified polymorphic DNA. Antifungal susceptibility of bloodstream isolates was determined against nine antifungals. Twenty-two ileostomy samples harboured at least one Candida species. Fungaemia were caused by Candida parapsilosis, Candida albicans, Candida glabrata, Candida orthopsilosis and Candida pelliculosa. All but three bloodstream isolates showed susceptibility to all the antifungals tested. One C. glabrata isolate showed multidrug resistance to itraconazole, amphotericin B and posaconazole and intermediate resistance to caspofungin. Results are congruent with both endogenous (C. albicans, C. glabrata) and exogenous (C. parapsilosis) infections; results also suggest two patients were infected by the same strain of C. parapsilosis. Continuing to work towards a better understanding of sources of infection-particularly the exogenous sources-would lead to targeted prevention strategies. © 2017 Blackwell Verlag GmbH.

Candida utilis and Cyberlindnera (Pichia) jadinii: yeast relatives with expanding applications.

PubMed

Buerth, Christoph; Tielker, Denis; Ernst, Joachim F

2016-08-01

The yeast Candida utilis is used as a food additive and as a host for heterologous gene expression to produce various metabolites and proteins. Reliable protocols for intracellular production of recombinant proteins are available for C. utilis and have now been expanded to secrete proteins into the growth medium or to achieve surface display by linkage to a cell wall protein. A recombinant C. utilis strain was recently shown to induce oral tolerance in a mouse model of multiple sclerosis suggesting future applications in autoimmune therapy. Whole genome sequencing of C. utilis and its presumed parent Cyberlindnera (Pichia) jadinii demonstrated different ploidy but high sequence identity, consistent with identical recombinant technologies for both yeasts. C. jadinii was recently described as an antagonist to the important human fungal pathogen Candida albicans suggesting its use as a probiotic agent. The review summarizes the status of recombinant protein production in C. utilis, as well as current and future biotechnological and medical applications of C. utilis and C. jadinii.

Use of restriction fragment length polymorphism to identify Candida species, related to onychomycosis

PubMed Central

Mohammadi, Rasoul; Badiee, Parisa; Badali, Hamid; Abastabar, Mahdi; Safa, Ahmad Hosseini; Hadipour, Mahboubeh; Yazdani, Hajar; Heshmat, Farnaz

2015-01-01

Background: Onychomycosis is one of the most common clinical forms of fungal infections due to both filamentous fungi and yeasts. The genus of Candida is one of the most prominent causes of onychomycosis in all around the world. Although Candida albicans is still the most frequent cause of nail infections, use of broad-spectrum antifungal agents has led to a shift in the etiology of C. albicans to non-albicans species. The aim of the present study is rapid and precise identification of candida species isolated from nail infection by using of PCR-RFLP technique. Materials and Methods: A total of 360 clinical yeast strains were collected from nail infections in Iran. Genomic DNA was extracted using FTA; cards. ITS1-5.8SrDNA-ITS2 region was amplified using universal primers and subsequently products were digested with the restriction enzyme MspI. For identification of newly described species (C. parapsilosis complex), the SADH gene was amplified, followed by digestion with Nla III restriction enzyme. Results: Candida albicans was the most commonly isolated species (41.1%), followed by C. parapsilosis (21.4%), C. tropicalis (12.8%), C. kefyr (9.4%), C. krusei (5.5%), C. orthopsilosis (4.1%), C. glabrata (2.8%), C. guilliermondii (1.4%), C. rugosa (0.8%), and C. lusitaniae (0.5%). Patients in the age groups of 51-60 and 81-90 years had the highest and lowest distribution of positive specimens, respectively. Conclusion: Rapid and precise identification of Candida species from clinical specimens lead to appropriate therapeutic plans. PMID:26015921

Portrait of Candida Species Biofilm Regulatory Network Genes.

PubMed

Araújo, Daniela; Henriques, Mariana; Silva, Sónia

2017-01-01

Most cases of candidiasis have been attributed to Candida albicans, but Candida glabrata, Candida parapsilosis and Candida tropicalis, designated as non-C. albicans Candida (NCAC), have been identified as frequent human pathogens. Moreover, Candida biofilms are an escalating clinical problem associated with significant rates of mortality. Biofilms have distinct developmental phases, including adhesion/colonisation, maturation and dispersal, controlled by complex regulatory networks. This review discusses recent advances regarding Candida species biofilm regulatory network genes, which are key components for candidiasis. Copyright © 2016 Elsevier Ltd. All rights reserved.

Use of the VITEK 2 system to identify and test the antifungal susceptibility of clinically relevant yeast species

PubMed Central

Melhem, MSC; Bertoletti, A; Lucca, HRL; Silva, RBO; Meneghin, FA; Szeszs, MW

2013-01-01

Eleven quality control isolates (Candida albicans ATCC 64548, C. tropicalis ATCC 200956, C. glabrata ATCC 90030, C. lusitaniae ATCC 200951, C. parapsilosis ATCC 22019, C. krusei ATCC 6258, C. dubliniensis ATCC 6330, Saccharomyces cerevisiae ATCC 9763, Cryptococcus neoformans ATCC 90012, C. gattii FIOCRUZ-CPF 60, and Trichosporon mucoides ATCC 204094) and 32 bloodstream isolates, including C. albicans, C. tropicalis, C. parapsilosis, C. glabrata, C. krusei, C. guilliermondii, C. pelliculosa (Pichia anomala), C. haemulonii, C. lusitaniae, and C. kefyr were identified at the species level by the VITEK 2 system. A set of clinical isolates (32 total) were used as challenge strains to evaluate the ability of the VITEK 2 system to determine the antifungal susceptibility of yeasts compared with the CLSI and EUCAST BMD reference standards. The VITEK 2 system correctly identified 100% of the challenge strains. The identification of yeast species and the evaluation of their susceptibility profiles were performed in an automated manner by the VITEK 2 system after approximately 15 h of growth for most species of Candida. The VITEK 2 system ensures that each test is performed in a standardized manner and provides quantitative MIC results that are reproducible and accurate when compared with the BMD reference methods. This system was able to determine the MICs of amphotericin B, flucytosine, voriconazole, and fluconazole in 15 h or less for the most common clinically relevant Candida species. In addition, the VITEK 2 system could reliably identify resistance to flucytosine, voriconazole, and fluconazole and exhibits excellent quantitative and qualitative agreement with the CLSI or EUCAST broth microdilution reference methods. PMID:24688520

Differential identification of Candida species and other yeasts by analysis of (/sup 35/S)methionine-labeled polypeptide profiles

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shen, H.D.; Choo, K.B.; Tsai, W.C.

1988-12-01

This paper describes a scheme for differential identification of Candida species and other yeasts based on autoradiographic analysis of protein profiles of (/sup 35/S)methionine-labeled cellular proteins separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Using ATCC strains as references, protein profile analysis showed that different Candida and other yeast species produced distinctively different patterns. Good agreement in results obtained with this approach and with other conventional systems was observed. Being accurate and reproducible, this approach provides a basis for the development of an alternative method for the identification of yeasts isolated from clinical specimens.

Candida amazonensis sp. nov., an ascomycetous yeast isolated from rotting wood in the Amazonian forest.

PubMed

Cadete, Raquel M; Melo, Monaliza A; Lopes, Mariana R; Pereira, Gilmara M D; Zilli, Jerri E; Vital, Marcos J S; Gomes, Fátima C O; Lachance, Marc-André; Rosa, Carlos A

2012-06-01

Five strains of a novel yeast species were isolated from rotting wood samples collected in an Amazonian forest site in the state of Roraima, northern Brazil. The sequences of the D1/D2 domains of the large subunit of the rRNA gene showed that this species belongs to the Scheffersomyces clade and is related to Candida coipomoensis, Candida lignicola and Candida queiroziae. The novel species Candida amazonensis sp. nov. is proposed to accommodate these isolates. The type strain of C. amazonensis sp. nov. is UFMG-HMD-26.3(T) ( = CBS 12363(T) = NRRL Y-48762(T)).

Rapid and reliable MALDI-TOF mass spectrometry identification of Candida non-albicans isolates from bloodstream infections.

PubMed

Pulcrano, Giovanna; Iula, Dora Vita; Vollaro, Antonio; Tucci, Alessandra; Cerullo, Monica; Esposito, Matilde; Rossano, Fabio; Catania, Maria Rosaria

2013-09-01

Matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry (MS) fingerprinting has recently become an effective instrument for rapid microbiological diagnostics and in particular for identification of micro-organisms directly in a positive blood culture. The aim of the study was to evaluate a collection of 82 stored yeast isolates from bloodstream infection, by MALDI-TOF MS; 21 isolates were identified also directly from positive blood cultures and in the presence of other co-infecting micro-organisms. Of the 82 isolates grown on plates, 64 (76%) were correctly identified by the Vitek II system and 82 (100%) by MALDI-TOF MS; when the two methods gave different results, the isolate was identified by PCR. MALDI-TOF MS was unreliable in identifying two isolates (Candida glabrata and Candida parapsilosis) directly from blood culture; however, direct analysis from positive blood culture samples was fast and effective for the identification of yeast, which is of great importance for early and adequate treatment. © 2013. Published by Elsevier B.V. All rights reserved.

Candida sirachaensis sp. nov. and Candida sakaeoensis sp. nov. two anamorphic yeast species from phylloplane in Thailand.

PubMed

Limtong, Savitree; Koowadjanakul, Nampueng; Jindamorakot, Sasitorn; Yongmanitchai, Wichien; Nakase, Takashi

2012-08-01

Three strains (LM008(T), LM068 and LM078(T)), representing two novel yeast species were isolated from the phylloplane of three plant species by an enrichment technique. On the basis of morphological, biochemical, physiological and chemotaxonomic characteristics, and the sequence analysis of the D1/D2 domain of the large subunit rRNA gene and the internal spacer region, the three strains were assigned as two novel Candida species. Strain LM008(T) was assigned to be Candida sirachaensis sp. nov. (type strain LM008(T) = BCC 47628(T) = NBRC 108605(T) CBS 12094(T)) in the Starmerella clade. Two strains (LM068 and LM078(T)) represent a single species in the Lodderomyces-Spathaspora clade for which the name Candida sakaeoensis sp. nov. is proposed with the type strain LM078(T) = BCC 47632(T) = NBRC 108895(T) = CBS 12318(T).

Presumptive identification of Candida species other than C. albicans, C. krusei, and C. tropicalis with the chromogenic medium CHROMagar Candida

PubMed Central

Hospenthal, Duane R; Beckius, Miriam L; Floyd, Karon L; Horvath, Lynn L; Murray, Clinton K

2006-01-01

Background CHROMagar Candida (CaC) is increasingly being reported as a medium used to differentiate Candida albicans from non-albicans Candida (NAC) species. Rapid identification of NAC can assist the clinician in selecting appropriate antifungal therapy. CaC is a differential chromogenic medium designed to identify C. albicans, C. krusei, and C. tropicalis based on colony color and morphology. Some reports have proposed that CaC can also reliably identify C. dubliniensis and C. glabrata. Methods We evaluated the usefulness of CaC in the identification of C. dubliniensis, C. famata, C. firmetaria, C. glabrata, C. guilliermondii, C. inconspicua, C. kefyr, C. lipolytica, C. lusitaniae, C. norvegensis, C. parapsilosis, and C. rugosa. Results Most NAC produced colonies that were shades of pink, lavender, or ivory. Several isolates of C. firmetaria and all C. inconspicua produced colonies difficult to differentiate from C. krusei. Most C. rugosa isolates produced unique colonies with morphology like C. krusei except in a light blue-green color. C. glabrata isolates produced small dark violet colonies that could be differentiated from the pink and lavender colors produced by other species. All seventeen isolates of C. dubliniensis produced green colonies similar to those produced by C. albicans. Conclusion C. glabrata and C. rugosa appear distinguishable from other species using CaC. Some NAC, including C. firmetaria and C. inconspicua, could be confused with C. krusei using this medium. PMID:16390552

Identification of salivary components that induce transition of hyphae to yeast in Candida albicans.

PubMed

Leito, Jelani T D; Ligtenberg, Antoon J M; Nazmi, Kamran; Veerman, Enno C I

2009-10-01

Candida albicans, the major human fungal pathogen, undergoes a reversible morphological transition from single yeast cells to pseudohyphae and hyphae filaments. The hyphae form is considered the most invasive form of the fungus. The purpose of this study is to investigate the effect of saliva on hyphae growth of C. albicans. Candida albicans hyphae were inoculated in Roswell Park Memorial Institute medium with whole saliva, parotid saliva or buffer mimicking the saliva ion composition, and cultured for 18 h at 37 degrees C under aerobic conditions with 5% CO(2). Whole saliva and parotid saliva induced transition to yeast growth, whereas the culture with buffer remained in the hyphae form. Parotid saliva was fractionated on a reverse-phase C8 column and each fraction was tested for inducing transition to yeast growth. By immunoblotting, the salivary component in the active fraction was identified as statherin, a phosphoprotein of 43 amino acids that has been implicated in remineralization of the teeth. Synthetically made statherin induced transition of hyphae to yeast. By deletion of five amino acids at the negatively charged N-terminal site (DpSpSEE), yeast-inducing activity and binding to C. albicans were increased. In conclusion, statherin induces transition to yeast of C. albicans hyphae and may thus contribute to the oral defense against candidiasis.

Inhibitory effect of alpha-mangostin on Candida biofilms.

PubMed

Kaomongkolgit, Ruchadaporn; Jamdee, Kusuma

2017-04-01

The objective of this study was to determine the inhibitory effect of alpha-mangostin on Candida biofilms. Candida species including Candida albicans, Candida krusei, Candida tropicalis, and Candida glabrata were tested. Candida biofilms were formed in flat-bottomed 96-well microtiter plates. The metabolic activity of cells within biofilms was quantified using the XTT assay. The results demonstrated that alpha-mangostin showed a significant anti-biofilm effect on both developing biofilms and preformed biofilms of Candida species. It may be concluded that alpha-mangostin could be an anti-biofilm agent against Candida species. Further in vivo investigations are needed to uncover the therapeutic values of this medicinal plant.

Oral Candida albicans isolates from HIV-positive individuals have similar in vitro biofilm-forming ability and pathogenicity as invasive Candida isolates

PubMed Central

2011-01-01

Background Candida can cause mucocutaneous and/or systemic infections in hospitalized and immunosuppressed patients. Most individuals are colonized by Candida spp. as part of the oral flora and the intestinal tract. We compared oral and systemic isolates for the capacity to form biofilm in an in vitro biofilm model and pathogenicity in the Galleria mellonella infection model. The oral Candida strains were isolated from the HIV patients and included species of C. albicans, C. glabrata, C. tropicalis, C. parapsilosis, C. krusei, C. norvegensis, and C. dubliniensis. The systemic strains were isolated from patients with invasive candidiasis and included species of C. albicans, C. glabrata, C. tropicalis, C. parapsilosis, C. lusitaniae, and C. kefyr. For each of the acquired strains, biofilm formation was evaluated on standardized samples of silicone pads and acrylic resin. We assessed the pathogenicity of the strains by infecting G. mellonella animals with Candida strains and observing survival. Results The biofilm formation and pathogenicity in Galleria was similar between oral and systemic isolates. The quantity of biofilm formed and the virulence in G. mellonella were different for each of the species studied. On silicone pads, C. albicans and C. dubliniensis produced more biofilm (1.12 to 6.61 mg) than the other species (0.25 to 3.66 mg). However, all Candida species produced a similar biofilm on acrylic resin, material used in dental prostheses. C. albicans, C. dubliniensis, C. tropicalis, and C. parapsilosis were the most virulent species in G. mellonella with 100% of mortality, followed by C. lusitaniae (87%), C. novergensis (37%), C. krusei (25%), C. glabrata (20%), and C. kefyr (12%). Conclusions We found that on silicone pads as well as in the Galleria model, biofilm formation and virulence depends on the Candida species. Importantly, for C. albicans the pathogenicity of oral Candida isolates was similar to systemic Candida isolates, suggesting that Candida

Molecular identification and distribution profile of Candida species isolated from Iranian patients.

PubMed

Mohammadi, Rasoul; Mirhendi, Hossein; Rezaei-Matehkolaei, Ali; Ghahri, Mohammad; Shidfar, Mohammad Reza; Jalalizand, Nilufar; Makimura, Koichi

2013-08-01

A total of 855 yeast strains isolated from different clinical specimens, mainly nail (42%) and vulva-vagina (25%) were identified by a set of polymerase chain reaction-restriction fragment length polymorphisms (PCR-RFLP). Genomic DNA was extracted from fresh colonies using Whatman FTA Card technology. PCR assays were performed on the complete ribosomal DNA internal transcribed spacer (rDNA-ITS) region for all isolates and species identification was carried out through their specific electrophoretic profiles after digestion with the enzyme MspI. Those isolates suspected as Candida parapsilosis group were then subjected to amplification of the secondary alcohol dehydrogenase (SADH) gene and restriction digestion with NlaIII enzyme. In total, 71.1% of the strains were obtained from females and 28.9% from males. The age group of 31-40 years consisted of the highest frequency of patients with candidiasis. Candida albicans was the predominant species (58.6%) followed by C. parapsilosis (11.0%), C. glabrata (8.3%), C. tropicalis (7.0%), C. kefyr (5.8%), C. krusei (4.4%), C. orthopsilosis (2.1%), and C. guilliermondii (0.6%). A few strains of C. lusitaniae, C. rugosa, C. intermedia, C. inconspicua, C. neoformans and S. cerevisiae were isolated. We could not identify 8 (0.9%) isolates. Candida albicans remains the most frequently species isolated from Iranian patients; however, the number of non-C. albicans Candida species looks to be increasing. The simple and reliable PCR-RFLP system used in the study has the potential to identify most clinically isolated yeasts.

Purification, Reconstitution, and Inhibition of Cytochrome P-450 Sterol Δ22-Desaturase from the Pathogenic Fungus Candida glabrata

PubMed Central

Lamb, David C.; Maspahy, Segula; Kelly, Diane E.; Manning, Nigel J.; Geber, Antonia; Bennett, John E.; Kelly, Steven L.

1999-01-01

Sterol Δ22-desaturase has been purified from a strain of Candida glabrata with a disruption in the gene encoding sterol 14α-demethylase (cytochrome P-45051; CYP51). The purified cytochrome P-450 exhibited sterol Δ22-desaturase activity in a reconstituted system with NADPH–cytochrome P-450 reductase in dilaurylphosphatidylcholine, with the enzyme kinetic studies revealing a Km for ergosta-5,7-dienol of 12.5 μM and a Vmax of 0.59 nmol of this substrate metabolized/min/nmol of P-450. This enzyme is encoded by CYP61 (ERG5) in Saccharomyces cerevisiae, and homologues have been shown in the Candida albicans and Schizosaccharomyces pombe genome projects. Ketoconazole, itraconazole, and fluconazole formed low-spin complexes with the ferric cytochrome and exhibited type II spectra, which are indicative of an interaction between the azole moiety and the cytochrome heme. The azole antifungal compounds inhibited reconstituted sterol Δ22-desaturase activity by binding to the cytochrome with a one-to-one stoichiometry, with total inhibition of enzyme activity occurring when equimolar amounts of azole and cytochrome P-450 were added. These results reveal the potential for sterol Δ22-desaturase to be an antifungal target and to contribute to the binding of drugs within the fungal cell. PMID:10390230

The Reconstruction of Condition-Specific Transcriptional Modules Provides New Insights in the Evolution of Yeast AP-1 Proteins

PubMed Central

Goudot, Christel; Etchebest, Catherine

2011-01-01

AP-1 proteins are transcription factors (TFs) that belong to the basic leucine zipper family, one of the largest families of TFs in eukaryotic cells. Despite high homology between their DNA binding domains, these proteins are able to recognize diverse DNA motifs. In yeasts, these motifs are referred as YRE (Yap Response Element) and are either seven (YRE-Overlap) or eight (YRE-Adjacent) base pair long. It has been proposed that the AP-1 DNA binding motif preference relies on a single change in the amino acid sequence of the yeast AP-1 TFs (an arginine in the YRE-O binding factors being replaced by a lysine in the YRE-A binding Yaps). We developed a computational approach to infer condition-specific transcriptional modules associated to the orthologous AP-1 protein Yap1p, Cgap1p and Cap1p, in three yeast species: the model yeast Saccharomyces cerevisiae and two pathogenic species Candida glabrata and Candida albicans. Exploitation of these modules in terms of predictions of the protein/DNA regulatory interactions changed our vision of AP-1 protein evolution. Cis-regulatory motif analyses revealed the presence of a conserved adenine in 5′ position of the canonical YRE sites. While Yap1p, Cgap1p and Cap1p shared a remarkably low number of target genes, an impressive conservation was observed in the YRE sequences identified by Yap1p and Cap1p. In Candida glabrata, we found that Cgap1p, unlike Yap1p and Cap1p, recognizes YRE-O and YRE-A motifs. These findings were supported by structural data available for the transcription factor Pap1p (Schizosaccharomyces pombe). Thus, whereas arginine and lysine substitutions in Cgap1p and Yap1p proteins were reported as responsible for a specific YRE-O or YRE-A preference, our analyses rather suggest that the ancestral yeast AP-1 protein could recognize both YRE-O and YRE-A motifs and that the arginine/lysine exchange is not the only determinant of the specialization of modern Yaps for one motif or another. PMID:21695268

Carboxymethylated ɩ-carrageenan conjugated amphotericin B loaded gelatin nanoparticles for treating intracellular Candida glabrata infections.

PubMed

Aparna, V; Melge, Anu Rohit; Rajan, V K; Biswas, Raja; Jayakumar, R; Gopi Mohan, C

2018-04-15

Intercellular Candida glabrata infections are difficult to treat due to poor penetration of drugs into the fungal niche. Delivering amphotericin B (Amp B) into the macrophages where the pathogen inhabits is an effective solution. We are studying the macrophage targeting proficiency of ɩ-carrageenan for the delivery of Amp B using gelatin A nanoparticles (GNPs). The choice of gelatin A was the outcome of in silico inspections where the amino functionalized polymer having the best docking score with Amp B was selected. We prepared a sustained release formulation of amp B loaded carboxymethyl ɩ-carrageenan conjugated gelatin nanoparticles (CMC-Amp B-GNPs) with size 343±12nm and -25±5.3mV zeta potential. The formulations were found to be stable, biocompatible and non-haemolytic. Flow cytometry analysis showed 3 fold higher uptake of CMC-GNPs compared to the GNPs by RAW 264.7 cells. CMC-Amp B-GNPs showed enhanced antifungal activity than bare Amp B and Amp B-GNPs. Copyright © 2017 Elsevier B.V. All rights reserved.

Introducing fluorescence resonance energy transfer-based biosensors for the analysis of cAMP-PKA signalling in the fungal pathogen Candida glabrata.

PubMed

Demuyser, Liesbeth; Van Genechten, Wouter; Mizuno, Hideaki; Colombo, Sonia; Van Dijck, Patrick

2018-05-29

The cyclic adenosine monophosphate-protein kinase A (cAMP-PKA) pathway is central to signal transduction in many organisms. In pathogenic fungi such as Candida albicans, this signalling cascade has proven to be involved in several processes, such as virulence, indicating its potential importance in antifungal drug discovery. Candida glabrata is an upcoming pathogen of the same species, yet information regarding the role of cAMP-PKA signalling in virulence is largely lacking. To enable efficient monitoring of cAMP-PKA activity in this pathogen, we here present the usage of two FRET-based biosensors. Both variations in the activity of PKA and the quantity of cAMP can be detected in a time-resolved manner, as we exemplify by glucose-induced activation of the pathway. We also present information on how to adequately process and analyse the data in a mathematically correct and physiologically relevant manner. These sensors will be of great benefit for scientists interested in linking the cAMP-PKA signalling cascade to downstream processes, such as virulence, possibly in a host environment. © 2018 John Wiley & Sons Ltd.

Antifungal susceptibilities of Candida species isolated from urine culture.

PubMed

Toka Özer, Türkan; Durmaz, Süleyman; Yula, Erkan

2016-09-01

Candida spp. are the most common opportunistic mycosis worldwide. Although Candida albicans is the most common cause of urinary tract infections, the frequency of non-albicans Candida species is increasing with common use of antifungal in the prophylaxis and treatment. This may lead to difficulties in treatment. Antifungal tests should be applied with identification of species for effective treatment. In this study, identification of Candida species isolated from urine culture and investigation of susceptibility of these strains to amphotericin B, flucytosine, fluconazole, voriconazole was aimed. In this study, 58 Candida strains isolated from urine cultures at Osmaniye State Hospital between January 2012 and April 2013 were included. Urine culture and antifungal susceptibility tests were applied. Incidence rate of Candida spp. was determined as C. albicans (56.9%), Candida glabrata (20.6%), Candida tropicalis (10.3%), Candida parapsilosis (7%), Candida krusei (3.4%), Candida kefyr (1.8%). Most of the isolates were susceptible to amphotericin B, flucytosine, fluconazole, voriconazole. Twenty three (39.7%) Candida strains were isolated from internal medical branches and Intensive Care Unit and 12 (20.6%) from the Surgical Medical Branches. C. albicans and C. glabrata species were isolated most frequently as a candiduria factor in this hospital between January 2012 and April 2013. The analysis of antifungal susceptibility profile shows no significant resistance to antifungals. Copyright © 2016 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

Azole Antifungal Resistance in Candida albicans and Emerging Non-albicans Candida Species

PubMed Central

Whaley, Sarah G.; Berkow, Elizabeth L.; Rybak, Jeffrey M.; Nishimoto, Andrew T.; Barker, Katherine S.; Rogers, P. David

2017-01-01

Within the limited antifungal armamentarium, the azole antifungals are the most frequent class used to treat Candida infections. Azole antifungals such as fluconazole are often preferred treatment for many Candida infections as they are inexpensive, exhibit limited toxicity, and are available for oral administration. There is, however, extensive documentation of intrinsic and developed resistance to azole antifungals among several Candida species. As the frequency of azole resistant Candida isolates in the clinical setting increases, it is essential to elucidate the mechanisms of such resistance in order to both preserve and improve upon the azole class of antifungals for the treatment of Candida infections. This review examines azole resistance in infections caused by C. albicans as well as the emerging non-albicans Candida species C. parapsilosis, C. tropicalis, C. krusei, and C. glabrata and in particular, describes the current understanding of molecular basis of azole resistance in these fungal species. PMID:28127295

Antibiofilm activity of carboxymethyl chitosan on the biofilms of non-Candida albicans Candida species.

PubMed

Tan, Yulong; Leonhard, Matthias; Moser, Doris; Schneider-Stickler, Berit

2016-09-20

Although most cases of candidiasis have been attributed to Candida albicans, non-C. albicans Candida species have been isolated in increasing numbers in patients. In this study, we determined the inhibition of carboxymethyl chitosan (CM-chitosan) on single and mixed species biofilm of non-albicans Candida species, including Candida tropicalis, Candida parapsilosis, Candida krusei and Candida glabrata. Biofilm by all tested species in microtiter plates were inhibited nearly 70%. CM-chitosan inhibited mixed species biofilm in microtiter plates and also on medical materials surfaces. To investigate the mechanism, the effect of CM-chitosan on cell viability and biofilm growth was employed. CM-chitosan inhibited Candida planktonic growth as well as adhesion. Further biofilm formation was inhibited with CM-chitosan added at 90min, 12h or 24h after biofilm initiation. CM-chitosan was not only able to inhibit the metabolic activity of Candida cells, but was also active upon the establishment and the development of biofilms. Copyright © 2016 Elsevier Ltd. All rights reserved.

Candida pruni sp. nov. is a new yeast species with antagonistic potential against brown rot of peaches.

PubMed

Zhang, Dian-peng; Lu, Cai-ge; Zhang, Tao-tao; Spadaro, Davide; Liu, De-wen; Liu, Wei-cheng

2014-07-01

Brown rot caused by Monilinia spp. is among the most important postharvest diseases of commercially grown stone fruits, and application of antagonistic yeasts to control brown rot is one promising strategy alternative to chemical fungicides. In this research, new yeast strains were isolated and tested for their activity against peach brown rot caused by Monilinia fructicola. Three yeast strains were originally isolated from the surface of plums (cv Chinese Angelino) collected in the north of China. In artificially wounded inoculation tests, the yeast reduced the brown rot incidence to 20 %. The population of the yeast within inoculated wounds on peaches significantly increased at 25 °C from an initial level of 5.0×10(6) to 4.45×10(7) CFU per wound after 1 day. The antagonistic strains were belonging to a new species of the genus Candida by sequence comparisons of 26 S rDNA D1/D2 domain and internal transcribed spacer region. The strains are most closely related to C. asparagi, C. musae and C. fructus on the basis of the phylogenetic trees based on the D1/D2 region of 26S rDNA. However, the strains are notably different from C. asparagi, C. musae and C. fructus, in morphological and physiological characteristics. Therefore, the name Candida pruni is proposed for the novel species, with sp-Quan (=CBS12814T=KCTC 27526T=GCMC 6582T) as the type strain. Our study showed that Candida pruni is a novel yeast species with potential biocontrol against brown rot caused by M. fructicola on peaches.

Candida ficus sp. nov., a novel yeast species from the gut of Apriona germari larvae.

PubMed

Hui, Feng-Li; Niu, Qiu-Hong; Ke, Tao; Liu, Zheng

2012-11-01

A novel yeast species is described based on three strains from the gut of wood-boring larvae collected in a tree trunk of Ficus carica cultivated in parks near Nanyang, central China. Phylogenetic analysis based on sequences of the D1/D2 domains of the large subunit rRNA gene showed that these strains occurred in a separate clade that was genetically distinct from all known ascomycetous yeasts. In terms of pairwise sequence divergence, the novel strains differed by 15.3% divergence from the type strain of Pichia terricola, and by 15.8% divergence from the type strains of Pichia exigua and Candida rugopelliculosa in the D1/D2 domains. All three are ascomycetous yeasts in the Pichia clade. Unlike P. terricola, P. exigua and C. rugopelliculosa, the novel isolates did not ferment glucose. The name Candida ficus sp. nov. is proposed to accommodate these highly divergent organisms, with STN-8(T) (=CICC 1980(T)=CBS 12638(T)) as the type strain.

Candida vaginitis during contraceptive use: the influence of methods, antifungal susceptibility and virulence patterns.

PubMed

Güzel, A B; Küçükgöz-Güleç, U; Aydin, M; Gümral, R; Kalkanci, A; Ilkit, M

2013-11-01

No consensus exists about whether contraceptives cause an increased risk of vaginitis, including vulvovaginal candidosis (VVC). We investigated 495 women (252 who used contraceptives; 243 who did not) for the presence of VVC. Antifungal susceptibility testing was performed for five antifungal agents and for boric acid, and three virulence factors were also examined. We recovered 129 (26.1%) monofungal populations from vaginal samples of women with acute VVC (AVVC, n = 18), symptomatic recurrent VVC (RVVC, n = 22) and asymptomatic RVVC (n = 28), as well as of other contraceptive users who carried Candida in their vaginas (n = 61). It is important to note that the women who had VVC used the same contraceptive methods (p > 0.05). Candida albicans was the most common species isolated (45%), followed by C. glabrata (40.3%). Most of the vaginal yeast isolates exhibited low minimum inhibitory concentration levels for the five antifungals tested. However, this was not the case for boric acid. In addition, the yeast fungi that was derived from the AVVC and RVVC patients showed higher amounts of haemolytic activity than the yeast fungi found among the controls (p < 0.05). The use of contraception does not predispose women to VVC (p > 0.05). Also, both host- and organism-related factors were required to achieve optimal clinical treatment for VVC.

Candida sanyaensis sp. nov., an ascomycetous yeast species isolated from soil.

PubMed

Hui, Feng-Li; Niu, Qiu-Hong; Ke, Tao; Li, Ying-Xia; Lee, Ching-Fu

2013-01-01

Strains representing a novel ascomycetous yeast species, Candida sanyaensis, were isolated from soil samples collected on Hainan Island and Taiwan Island in China. Analysis of the D1/D2 domains of the large subunit (LUS) rRNA gene and internal transcribed spacer (ITS) regions of these strains showed that this species was related to Candida tropicalis and Candida sojae, their closest relatives. C. sanyaensis differed by three substitutions and one gap from C. tropicalis, and by four substitutions and one gap from C. sojae, in the D1/D2 domain sequences. However, the ITS sequences of C. sanyaensis were quite divergent from the latter two species, showing that it is a genetically separate species. The novel strains were also found to have very similar PCR-fingerprinting profiles which were quite distinct from those of C. tropicalis and C. sojae strains. The type strain of C. sanyaensis is HN-26(T) (= CICC 1979(T) = CBS 12637(T)).

Candida wancherniae sp. nov. and Candida morakotiae sp. nov., two novel ascomycetous anamorphic yeast species found in Thailand.

PubMed

Nakase, Takashi; Jindamorakot, Sasitorn; Ninomiya, Shinya; Imanishi, Yumi; Kawasaki, Hiroko

2009-04-01

Seven yeast strains isolated from natural substrates of Thailand were found to represent two novel species of Candida, an ascomycetous anamorphic genus. Three strains, ST-233, ST-259 and ST-260, isolated from insect frass and plant leaves were found to represent a single novel species related to Metschnikowia agaves in a tree based on the D1/D2 domain sequences of the 26S rRNA genes. This species is clearly discriminated from M. agaves by the carbon assimilation patterns and required vitamins. The remaining four strains, ST-18, ST-261, ST-606 and ST-658, isolated from the fruit body of a mushroom, insect frass, decayed jack fruit and an unidentified flower, were found to represent a single species which is related to Candida corydali, a recently described insect-associated species, in a neighbor-joining tree based on the D1/D2 sequences. This species is clearly discriminated from C. corydali by the ability to assimilate propane-1,2-diol and the inability to assimilate glucono-delta-lactone. They are described as Candida wancherniae sp. nov. and Candida morakotiae sp. nov., respectively.

[National Trends in the Distribution of Candida Species Causing Candidemia in Japan from 2003 to 2014].

PubMed

Kakeya, Hiroshi; Yamada, Koichi; Kaneko, Yukihiro; Yanagihara, Katsunori; Tateda, Kazuhiro; Maesaki, Shigefumi; Takesue, Yoshio; Tomono, Kazunori; Kadota, Jun-Ichi; Kaku, Mitsuo; Miyazaki, Yoshitsugu; Kamei, Katsuhiko; Shibuya, Kazutoshi; Niki, Yoshitiho; Yoshida, Minoru; Sei, Yoshihiro

2018-01-01

The Epidemiological Investigation Committee for Human Mycoses in Japan performed a retrospective epidemiological survey of candidemia and causative Candida species. Data from 2003 to 2014 were collected from 10 Japanese university hospitals. A total of 328,318 blood cultures were included. The prevalence of fungi in all cultures and in positive cultures were 0.58±0.09% and 4.46±0.66%, respectively. Among the results that were positive for Candida species (N=1,921), Candida albicans was the most common species (39.5%) and was followed by Candida parapsilosis (23.3%), Candida glabrata (13.2%), Candida tropicalis (7.1%), Candida krusei (3.2%), and others (13.7%). During the last 6 years, the frequency of C. albicans has significantly decreased in Japan, while that of C. glabrata has increased. Additional surveys are needed to continuously monitor the trends in the distribution of candidemia.

Molecular characterization of the silencing complex SIR in Candida glabrata hyperadherent clinical isolates.

PubMed

Leiva-Peláez, Osney; Gutiérrez-Escobedo, Guadalupe; López-Fuentes, Eunice; Cruz-Mora, José; De Las Peñas, Alejandro; Castaño, Irene

2018-05-29

An important virulence factor for the fungal pathogen Candida glabrata is the ability to adhere to the host cells, which is mediated by the expression of adhesins. Epa1 is responsible for ∼95% of the in vitro adherence to epithelial cells and is the founding member of the Epa family of adhesins. The majority of EPA genes are localized close to different telomeres, which causes transcriptional repression due to subtelomeric silencing. In C. glabrata there are three Sir proteins (Sir2, Sir3 and Sir4) that are essential for subtelomeric silencing. Among a collection of 79 clinical isolates, some display a hyperadherent phenotype to epithelial cells compared to our standard laboratory strain, BG14. These isolates also express several subtelomeric EPA genes simultaneously. We cloned the SIR2, SIR3 and SIR4 genes from the hyperadherent isolates and from the BG14 and the sequenced strain CBS138 in a replicative vector to complement null mutants in each of these genes in the BG14 background. All the SIR2 and SIR4 alleles tested from selected hyper-adherent isolates were functional and efficient to silence a URA3 reporter gene inserted in a subtelomeric region. The SIR3 alleles from these isolates were also functional, except the allele from isolate MC2 (sir3-MC2), which was not functional to silence the reporter and did not complement the hyperadherent phenotype of the BG14 sir3Δ. Consistently, sir3-MC2 allele is recessive to the SIR3 allele from BG14. Sir3 and Sir4 alleles from the hyperadherent isolates contain several polymorphisms and two of them are present in all the hyperadherent isolates analyzed. Instead, the Sir3 and Sir4 alleles from the BG14 and another non-adherent isolate do not display these polymorphisms and are identical to each other. The particular combination of polymorphisms in sir3-MC2 and in SIR4-MC2 could explain in part the hyperadherent phenotype displayed by this isolate. Copyright © 2018 Elsevier Inc. All rights reserved.

[Comparison between conventional methods, ChromAgar Candida® and PCR method for the identification of Candida species in clinical isolates].

PubMed

Estrada-Barraza, Deyanira; Dávalos Martínez, Arturo; Flores-Padilla, Luis; Mendoza-De Elias, Roberto; Sánchez-Vargas, Luis Octavio

2011-01-01

The increase in the incidence of yeast species causing fungemia in susceptible immunocompromised patients in the last two decades and the low sensitivity of conventional blood culture has led to the need to develop alternative approaches for the early detection and identification of causative species. The aim of this study was to compare the usefulness of molecular testing by the polymerase chain reaction (PCR) and conventional methods to identify clinical isolates of different species, using the ID32C ATB system (bioMérieux, France), chromogenic culture Chromagar Candida® (CHROMagar, France) and morphogenesis in corn meal agar. We studied 79 isolates, in which the most prevalent species using the system ID32C and PCR was C. albicans, followed by C. tropicalis, C. glabrata and C .krusei. PCR patterns obtained for the identification of clinical isolates were stable and consistent in the various independent studies and showed good reproducibility, concluding that PCR with species-specific primers that amplify genes ITS1 and ITS2 for rRNA or topoisomerase II primers is a very specific and sensitive method for the identification of C. glabrata, C. krusei, C. albicans, and with less specificity for C. tropicalis. Copyright © 2010 Revista Iberoamericana de Micología. Published by Elsevier Espana. All rights reserved.

Candida xylanilytica sp. nov., a xylan-degrading yeast species isolated from Thailand.

PubMed

Boonmak, Chanita; Limtong, Savitree; Jindamorakot, Sasitorn; Am-In, Somjit; Yongmanitchai, Wichien; Suzuki, Ken-ichiro; Nakase, Takashi; Kawasaki, Hiroko

2011-05-01

Xylan is a major component of hemicellulose, which constitutes about 40 % of plant biomass. Hydrolysis of xylan into simple sugars is one of the important steps in the conversion of lignocellulosic material to value-added products. During an investigation of cellulose- and xylan-degrading yeasts, two yeast strains that were able to use cellulose and xylan as sole carbon source were found to represent a phylogenetically distinct species in the Spathaspora clade. The closest species in terms of pairwise sequence similarity in the D1/D2 domain of the LSU rRNA gene was Candida subhashii. The novel species can be distinguished from the other species in the Spathaspora clade based on the ability to assimilate methanol and raffinose, growth in medium containing 60 % glucose, and growth at 42 °C. It ferments glucose but not other carbohydrates. The name Candida xylanilytica sp. nov. is proposed for this species. The type strain is KU-Xn11(T) ( = NBRC 106499(T)  = BCC 34694(T)  = CBS 11761(T)).

Echinocandin resistance among Candida isolates at an academic medical centre 2005-15: analysis of trends and outcomes.

PubMed

McCarty, Todd P; Lockhart, Shawn R; Moser, Stephen A; Whiddon, Jennifer; Zurko, Joanna; Pham, Cau D; Pappas, Peter G

2018-02-28

To identify the frequency of micafungin resistance among clinically significant isolates of Candida stored at our institution from 2005 to 2015. Chart review of patients with resistant isolates then informed the clinical setting and outcomes associated with these infections. Clinical Candida isolates had been stored at -80°C in Brucella broth with 20% glycerol from 2005. Isolates were tested using broth microdilution to determine micafungin MICs. All Candida glabrata isolates and all isolates demonstrating decreased susceptibility to micafungin were screened for FKS mutations using a Luminex assay. In total, 3876 Candida isolates were tested for micafungin resistance, including 832 C. glabrata isolates. Of those, 33 isolates from 31 patients were found to have either decreased susceptibility to micafungin and/or an FKS mutation. C. glabrata accounted for the majority of these isolates. While bloodstream infections were found to have a very high mortality rate, isolates from other sites were uncommonly associated with 30-day mortality. Overall resistance rates were very low. Echinocandin resistance in C. glabrata has been increasingly reported but rates at our institution remain very low. We hypothesize that a focus on antifungal stewardship may have led to these observations. Knowledge of local resistance patterns is key to appropriate empirical treatment strategies.

[Molecular epidemiology and antifungal susceptibility of Candida species isolated from urine samples of patients in intensive care unit].

PubMed

Yüksekkaya, Serife; Fındık, Duygu; Arslan, Uğur

2011-01-01

The aims of this study were to analyse the amphotericin B and fluconazole susceptibility and molecular epidemiology of Candida strains (Candida albicans, Candida tropicalis and Candida glabrata) isolated from the urine samples of patients hospitalized in the intensive care unit. Identification of the isolates was done according to microscopic morphology (chlamydospor, blastospor, pseudohyphae and true hyphae) on cornmeal agar, germ tube formation and carbohydrate assimilation patterns (API ID 32C bioMérieux, France). Antifungal susceptibilities of the isolates were determined by in vitro broth microdilution method recommended by Clinical and Laboratory Standards Institute (CLSI). To investigate the clonal relationship of the isolates, randomly amplified polymorphic DNA (RAPD) analysis was performed by using Cnd3 primer. Of the 56 Candida isolates minimum inhibitory concentration (MIC) ranges, MIC50 and MIC90 values for amphotericin B were 0.125-1 µg/ml, 0.125 and 0.5 µg/ml for C.albicans, 0.125-1 µg/ml, 0.25 and 1 µg/ml for C.tropicalis and 0.125-1 µg/ml, 0.25 and 1 µg/ml for C.glabrata, respectively. Fluconazole MIC ranges, MIC50 and MIC90 values were 0.25-4 µg/ml, 0.25 and 0.5 µg/ml for C.albicans, 0.25-16 µg/ml, 0.5 and 1 µg/ml for C.tropicalis and 0.5-64 µg/ml, 8 and 16 µg/ml for C.glabrata, respectively. For amphotericin B, none of the isolates had high MIC values (MIC > 1 µg/ml). While one of the C.glabrata isolates was resistant to fluconazole (MIC ≥ 64 µg/ml), one C.tropicalis and two C.glabrata isolates were dose-dependent susceptible (MIC: 16-32 µg/ml). The results of RAPD analysis indicated an exogenous spread from two clones for C.albicans, one clone for C.glabrata and one clone for C.tropicalis. This study underlines the importance of molecular epidemiological analysis of clinical samples together with hospital environmental samples in terms of Candida spp. To determine the exogenous origin for the related strains and to prevent

Species identification and antifungal susceptibility testing of Candida bloodstream isolates from population-based surveillance studies in two U.S. cities from 2008 to 2011.

PubMed

Lockhart, Shawn R; Iqbal, Naureen; Cleveland, Angela A; Farley, Monica M; Harrison, Lee H; Bolden, Carol B; Baughman, Wendy; Stein, Betsy; Hollick, Rosemary; Park, Benjamin J; Chiller, Tom

2012-11-01

Between 2008 and 2011, population-based candidemia surveillance was conducted in Atlanta, GA, and Baltimore, MD. Surveillance had been previously performed in Atlanta in 1992 to 1993 and in Baltimore in 1998 to 2000, making this the first population-based candidemia surveillance conducted over multiple time points in the United States. From 2,675 identified cases of candidemia in the current surveillance, 2,329 Candida isolates were collected. Candida albicans no longer comprised the majority of isolates but remained the most frequently isolated species (38%), followed by Candida glabrata (29%), Candida parapsilosis (17%), and Candida tropicalis (10%). The species distribution has changed over time; in both Atlanta and Baltimore the proportion of C. albicans isolates decreased, and the proportion of C. glabrata isolates increased, while the proportion of C. parapsilosis isolates increased in Baltimore only. There were 98 multispecies episodes, with C. albicans and C. glabrata the most frequently encountered combination. The new species-specific CLSI Candida MIC breakpoints were applied to these data. With the exception of C. glabrata (11.9% resistant), resistance to fluconazole was very low (2.3% of isolates for C. albicans, 6.2% for C. tropicalis, and 4.1% for C. parapsilosis). There was no change in the proportion of fluconazole resistance between surveillance periods. Overall echinocandin resistance was low (1% of isolates) but was higher for C. glabrata isolates, ranging from 2.1% isolates resistant to caspofungin in Baltimore to 3.1% isolates resistant to anidulafungin in Atlanta. Given the increase at both sites and the higher echinocandin resistance, C. glabrata should be closely monitored in future surveillance.

Species Identification and Antifungal Susceptibility Testing of Candida Bloodstream Isolates from Population-Based Surveillance Studies in Two U.S. Cities from 2008 to 2011

PubMed Central

Iqbal, Naureen; Cleveland, Angela A.; Farley, Monica M.; Harrison, Lee H.; Bolden, Carol B.; Baughman, Wendy; Stein, Betsy; Hollick, Rosemary; Park, Benjamin J.; Chiller, Tom

2012-01-01

Between 2008 and 2011, population-based candidemia surveillance was conducted in Atlanta, GA, and Baltimore, MD. Surveillance had been previously performed in Atlanta in 1992 to 1993 and in Baltimore in 1998 to 2000, making this the first population-based candidemia surveillance conducted over multiple time points in the United States. From 2,675 identified cases of candidemia in the current surveillance, 2,329 Candida isolates were collected. Candida albicans no longer comprised the majority of isolates but remained the most frequently isolated species (38%), followed by Candida glabrata (29%), Candida parapsilosis (17%), and Candida tropicalis (10%). The species distribution has changed over time; in both Atlanta and Baltimore the proportion of C. albicans isolates decreased, and the proportion of C. glabrata isolates increased, while the proportion of C. parapsilosis isolates increased in Baltimore only. There were 98 multispecies episodes, with C. albicans and C. glabrata the most frequently encountered combination. The new species-specific CLSI Candida MIC breakpoints were applied to these data. With the exception of C. glabrata (11.9% resistant), resistance to fluconazole was very low (2.3% of isolates for C. albicans, 6.2% for C. tropicalis, and 4.1% for C. parapsilosis). There was no change in the proportion of fluconazole resistance between surveillance periods. Overall echinocandin resistance was low (1% of isolates) but was higher for C. glabrata isolates, ranging from 2.1% isolates resistant to caspofungin in Baltimore to 3.1% isolates resistant to anidulafungin in Atlanta. Given the increase at both sites and the higher echinocandin resistance, C. glabrata should be closely monitored in future surveillance. PMID:22875889

Antifungal susceptibility patterns of colonized Candida species isolates from immunocompromised pediatric patients in five university hospitals.

PubMed

Badiee, Parisa; Choopanizadeh, Maral; Moghadam, Abdolkarim Ghadimi; Nasab, Ali Hossaini; Jafarian, Hadis; Shamsizadeh, Ahmad; Soltani, Jafar

2017-12-01

Colonization of Candida species is common in pediatric patients admitted to hematology-oncology wards. The aim of this study was to identify colonized Candida species and their susceptibility patterns in hematologic pediatric patients. Samples were collected from mouth, nose, urine and stool of the patients admitted to five university hospitals and cultured on sabouraud dextrose agar. The isolates were identified by API 20 C AUX system and their susceptibility patterns were evaluated by CLSI M27-A3 and S4. From 650 patients, 320 (49.2%) were colonized with 387 Candida species. Candida albicans was the most prevalent isolated species, followed by Candida glabrata, Candida tropicalis, Candida famata, Candida kefyr and Candida kuresi . The epidemiological cut off value (ECV) for all Candida species to amphotericin B was ≤0.25 μg except C. krusei (4 μg). The resistance rate to fluconazole in this study in C. albicans was 4.9% with ECV 8 μg/ml, followed by C. tropicalis 8.8% with ECV 0.5 μg/ml. Voriconazole and posaconazole were effective antifungal agents for all Candida isolates. The ECV of C. albicans, Candida parapsilosis, C. tropicalis, C. glabrata and C. krusei for itraconazole were 0.5, 0.25, 0.5, 1 and 2 μg, respectively. The resistant and intermediate rates of Candida species to caspofungin in this study were 2.9%, 5.9%, 18.8%, 47.9%, 0.0% and 16.7% in C. tropicalis, C. glabrata and C. parapsilosis respectively. C. albicans was the most prevalent species in pediatric colonized patients. New azole agents like voriconazole and posaconazole are effective against non-albicans Candida species. Increase in intermediate species is alarming to future emerging resistant species.

Multidrug-Resistant Candida: Epidemiology, Molecular Mechanisms, and Treatment.

PubMed

Arendrup, Maiken Cavling; Patterson, Thomas F

2017-08-15

Invasive Candida infections remain an important cause of morbidity and mortality, especially in hospitalized and immunocompromised or critically ill patients. A limited number of antifungal agents from only a few drug classes are available to treat patients with these serious infections. Resistance can be either intrinsic or acquired. Resistance mechanisms are not exchanged between Candida; thus, acquired resistance either emerges in response to an antifungal selection pressure in the individual patient or, more rarely, occur due to horizontal transmission of resistant strains between patients. Although multidrug resistance is uncommon, increasing reports of multidrug resistance to the azoles, echinocandins, and polyenes have occurred in several Candida species, most notably Candida glabrata and more recently Candida auris. Drivers are overall antifungal use, subtherapeutic drug levels at sites of infection/colonization, drug sequestration in the biofilm matrix, and, in the setting of outbreaks, suboptimal infection control. Moreover, recent research suggests that DNA mismatch repair gene mutations may facilitate acquisition of resistance mutations in C. glabrata specifically. Diagnosis of antifungal-resistant Candida infections is critical to the successful management of patients with these infections. Reduction of unnecessary use of antifungals via antifungal stewardship is critical to limit multidrug resistance emergence. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.

Candida Berkhout (1923)

USDA-ARS?s Scientific Manuscript database

This chapter describes the 314 species assigned to the genus Candida and is to be published in the Yeasts, A Taxonomic Study, 5th edition. Ascomycete yeasts that do not form ascosporic state are assigned to the genus Candida, which is a highly polyphyletic taxonomic form genus. Assigned species in...

[Effect of excess ethanol on the growth of yeasts of the genus Candida during continuous cultivation].

PubMed

Shkidchenko, A N; Shul'ga, A V; Gurina, L V

1988-01-01

The effect of flow rates and a specific ethanol load on the growth of Candida utilis and Candida krusei was studied in the process of one-step and three-step cultivation. The productive capacity of fermenters and the economic coefficient of yeast biomass production were shown to depend on the ability of microbial populations to assimilate a certain quantity of a carbon substrate per unit time. When a specific ethanol load exceeds the optimal one, the respiratory activity of a population and the economic coefficient of growth fall down whereas the accumulation of metabolites in the cultural broth increases. The steady state of biomass can be maintained in the process of continuous cultivation by inhibiting the yeast growth with an excess of ethanol.

Candida funiuensi sp. nov., a cellobiose-fermenting yeast species isolated from rotten wood.

PubMed

Wang, Yun; Ren, Yong-Cheng; Zhang, Zheng-Tian; Wu, Fu-Hua; Ke, Tao; Hui, Feng-Li

2015-06-01

Two strains of an asexual cellobiose-fermenting yeast species were isolated from rotten wood samples collected in Funiu Mountain Nature Reserve in Henan Province, central China. Molecular phylogenetic analysis that included the nearly complete small subunit (SSU), the internal transcribed spacer (ITS) region and the D1/D2 domains of the large subunit (LSU) rDNA showed that these strains belonged to the Candida kruisii clade, with Candida kruisii and Candida cretensis as their closest phylogenetic neighbours. The nucleotide differences between the novel strains and the type strains of C. kruisii and C. cretensis were 30 and 36 substitutions, respectively, in the D1/D2 LSU rDNA, 40 and 44 substitutions, respectively, in the ITS region and 19 and 23 substitutions, respectively, in the SSU rDNA. The novel strains can also be distinguished from their closest described species, C. kruisii and C. cretensis, by a number of physiological characteristics, and represent a novel species of the genus Candida, for which the name Candida funiuensis sp. nov. is proposed. The type strain is NYNU 14625T ( = CICC 33050T = CBS 13911T). The Mycobank number is MB 811503.

New Chromogenic Agar Medium for the Identification of Candida spp.

PubMed Central

Cooke, Venitia M.; Miles, R. J.; Price, R. G.; Midgley, G.; Khamri, W.; Richardson, A. C.

2002-01-01

A new chromogenic agar medium (Candida diagnostic agar [CDA]) for differentiation of Candida spp. is described. This medium is based on Sabouraud dextrose agar (Oxoid CM41) and contains (per liter) 40.0 g of glucose, 10.0 g of mycological peptone, and 15.0 g of agar along with a novel chromogenic glucosaminidase substrate, ammonium 4-{2-[4-(2-acetamido-2-deoxy-β-d-glucopyranosyloxy)-3-methoxyphenyl]-vinyl}-1-(propan-3-yl-oate)-quinolium bromide (0.32 g liter−1). The glucosaminidase substrate in CDA was hydrolyzed by Candida albicans and Candida dubliniensis, yielding white colonies with deep-red spots on a yellow transparent background after 24 to 48 h of incubation at 37°C. Colonies of Candida tropicalis and Candida kefyr were uniformly pink, and colonies of other Candida spp., including Candida glabrata and Candida parapsilosis, were white. CDA was evaluated by using 115 test strains of Candida spp. and other clinically important yeasts and was compared with two commercially available chromogenic agars (Candida ID agar [bioMerieux] and CHROMagar Candida [CHROMagar Company Ltd.]). On all three agars, colonies of C. albicans were not distinguished from colonies of C. dubliniensis. However, for the group containing C. albicans plus C. dubliniensis, both the sensitivity and the specificity of detection when CDA was used were 100%, compared with values of 97.6 and 100%, respectively, with CHROMagar Candida and 100 and 96.8%, respectively, with Candida ID agar. In addition, for the group containing C. tropicalis plus C. kefyr, the sensitivity and specificity of detection when CDA was used were also 100%, compared with 72.7 and 98.1%, respectively, with CHROMagar Candida. Candida ID agar did not differentiate C. tropicalis and C. kefyr strains but did differentiate members of a broader group (C. tropicalis, C. kefyr, Candida lusitaniae plus Candida guilliermondii); the sensitivity and specificity of detection for members of this group were 94.7 and 93

Biological diversity of yeasts in the gastrointestinal tract of weaned piglets kept under different farm conditions.

PubMed

Urubschurov, Vladimir; Janczyk, Pawel; Pieper, Robert; Souffrant, Wolfgang B

2008-12-01

The study was conducted to determine yeasts present in the gastrointestinal tract (GIT) of piglets kept under experimental farm (EF) and commercial farm (CF) conditions. Ninety five German Landrace full- and half-sibling piglets were sacrificed at 39 days of age. Sixty eight piglets were weaned at 28th day of life, when they were offered one diet ad libitum. Twenty seven piglets remained unweaned by their dams. None of the piglets received any creep feed before weaning. Digesta samples were collected from 1/3 distal small intestine (SI), caecum and proximal colon. One hundred seventy three colonies of isolated yeasts were characterized by sequence analysis of the PCR-amplified D1/D2 domain of the 26S rRNA gene with following alignment of the recovered sequences to GenBank entries. From the 17 phylotypes found, isolates most closely related to Galactomyces geotrichum, Kazachstania slooffiae and Candida catenulata dominated in the GIT of CF piglets. Kazachstania slooffiae and Candida glabrata dominated in GIT of EF piglets. Sørenson and Morisita-Horn similarity indices between farms were low (0.44 and 0.54 respectively) and the Simpson diversity index was higher for EF (7.58) than for CF (4.34). The study brings new data on yeasts composition in the pig GIT and shows differences in yeasts biodiversity between farms operated at different hygiene conditions.

Antifungal susceptibility of invasive Candida bloodstream isolates from the Asia-Pacific region.

PubMed

Tan, Thean Yen; Hsu, Li Yang; Alejandria, Marissa M; Chaiwarith, Romanee; Chinniah, Terrence; Chayakulkeeree, Methee; Choudhury, Saugata; Chen, Yen Hsu; Shin, Jong Hee; Kiratisin, Pattarachai; Mendoza, Myrna; Prabhu, Kavitha; Supparatpinyo, Khuanchai; Tan, Ai Ling; Phan, Xuan Thi; Tran, Thi Thanh Nga; Nguyen, Gia Binh; Doan, Mai Phuong; Huynh, Van An; Nguyen, Su Minh Tuyet; Tran, Thanh Binh; Van Pham, Hung

2016-07-01

Bloodstream infections caused by Candida species are of increasing importance and associated with significant mortality. We performed a multi-centre prospective observational study to identify the species and antifungal susceptibilities of invasive bloodstream isolates of Candida species in the Asia-Pacific region. The study was carried out over a two year period, involving 13 centers from Brunei, Philippines, Singapore, South Korea, Taiwan, Thailand, and Vietnam. Identification of Candida species was performed at each study center, and reconfirmed at a central laboratory. Susceptibility testing was performed using a commercial broth dilution panel (Sensititre YeastOne YST-010, Thermofisher, United Kingdom) with susceptibility categorisation (S = susceptible, S-DD = susceptible dose-dependent) applied using breakpoints from the Clinical Laboratory Standards Institute. Eight hundred and sixty-one Candida isolates were included in the study. The most common species were C. albicans (35.9%), C. tropicalis (30.7%), C. parapsilosis (15.7%), and C. glabrata (13.6%). Non-albicans species exceeded C. albicans species in centers from all countries except Taiwan. Fluconazole susceptibility was almost universal for C. albicans (S = 99.7%) but lower for C. tropicalis (S = 75.8%, S-DD = 6.1%), C. glabrata (S-DD = 94.9%), and C. parapsilosis (S = 94.8%). Echinocandins demonstrated high rates of in vitro susceptibility (S>99%) against C. albicans, C. tropicalis, and C. parapsilosis This study demonstrates that non-albicans species are the most common isolates from bloodstream infections in most countries in the Asia-Pacific region, with C. tropicalis as the predominant species. Because of the prevalence of reduced susceptibility to fluconazole in non-albicans species, the study indicates that echinocandins should be the antifungal of choice in clinically unstable or high-risk patients with documented candidemia. © The Author 2016. Published by Oxford

Direct identification and recognition of yeast species from clinical material by using albicans ID and CHROMagar Candida plates.

PubMed

Baumgartner, C; Freydiere, A M; Gille, Y

1996-02-01

Two chromogenic media, Albicans ID and CHROMagar Candida agar plates, were compared with a reference medium, Sabouraud-chloramphenicol agar, and standard methods for the identification of yeast species. This study involved 951 clinical specimens. The detection rates for the two chromogenic media for polymicrobial specimens were 20% higher than that for the Sabouraud-chloramphenicol agar plates. The rates of identification of Candida albicans for Albicans ID and CHROMagar Candida agar plates were, respectively, 37.0 and 6.0% after 24 h of incubation and 93.6 and 92.2% after 72 h of incubation, with specificities of 99.8 and 100%. Furthermore, CHROMagar Candida plates identified 13 of 14 Candida tropicalis and 9 of 12 Candida krusei strains after 48 h of incubation.

Candida xinjiangensis sp. nov., a new anamorphic yeast species isolated from Scolytus scheryrewi Semenov in China.

PubMed

Zhu, Xiao-Feng; Zhang, Dian-Peng; Yang, Sen; Zhang, Qing-Wen

2017-03-01

Three yeast strains designated as S44, XF1 and XF2, respectively, were isolated from Scolytus scheryrewi Semenov of apricot tree in Shule County, Xinjiang, China, and were demonstrated to be a new member of the genus Candida by sequence comparisons of 26S rRNA gene D1/D2 domain and internal transcribed spacer (ITS) region. BLASTn alignments on NCBI showed that the similarity of 26S rRNA gene sequences of S44 (type strain) to all sequences of other Candida yeasts was very low (≦93 %). The phylogenetic tree based on the 26S rRNA gene D1/D2 domain and ITS region sequences revealed that the strain S44 is closely related to C. blattae, C. dosseyi, C. pruni, C. asparagi, C. fructus and C. musae. However, the strain S44 is distinguished from these Candida species by the physiological characteristics. Moreover, the strain S44 formed typical pseudohyphae when grown on cornmeal agar at 25 °C for 7 days, but did not form ascospores in sporulation medium for 3-4 weeks. Therefore, the name Candida xinjiangensis is proposed for the novel species, with S44 (=KCTC T 27747) as the type strain.

Serum albumin promotes ATP-binding cassette transporter-dependent sterol uptake in yeast.

PubMed

Marek, Magdalena; Silvestro, Daniele; Fredslund, Maria D; Andersen, Tonni G; Pomorski, Thomas G

2014-12-01

Sterol uptake in fungi is a multistep process that involves interaction between external sterols and the cell wall, incorporation of sterol molecules into the plasma membrane, and subsequent integration into intracellular membranes for turnover. ATP-binding cassette (ABC) transporters have been implicated in sterol uptake, but key features of their activity remain to be elucidated. Here, we apply fluorescent cholesterol (NBD-cholesterol) to monitor sterol uptake under anaerobic and aerobic conditions in two fungal species, Candida glabrata (Cg) and Saccharomyces cerevisiae (Sc). We found that in both fungal species, ABC transporter-dependent uptake of cholesterol under anaerobic conditions and in mutants lacking HEM1 gene is promoted in the presence of the serum protein albumin that is able to bind the sterol molecule. Furthermore, the C. glabrata ABC transporter CgAus1p expressed in S. cerevisiae requires the presence of serum or albumin for efficient cholesterol uptake. These results suggest that albumin can serve as sterol donor in ABC transporter-dependent sterol uptake, a process potentially important for growth of C. glabrata inside infected humans. © 2014 The Authors. FEMS Yeast Research published by John Wiley & Sons Ltd on behalf of Federation of European Microbiological Societies.

The epidemiology of Candida species associated with vulvovaginal candidiasis in an Iranian patient population.

PubMed

Mahmoudi Rad, M; Zafarghandi, S; Abbasabadi, B; Tavallaee, M

2011-04-01

Vulvovaginal candidiasis is a common infection among women worldwide. According to previous epidemiological studies, Candida albicans is the most common species of Candida. The prevalence of non-Candida species, however, is increasing. Identification of Candida species among the population will not only help health professionals to choose suitable antifungal treatments, but also prevent development of drug resistance. The aim of this study was to identify, using chromogenic agar medium, the Candida species associated with vulvovaginal candidiasis among a sample of the Iranian population. In a prospective cohort study during a two year period from March 2006 to March 2008, swab samples of vaginal discharge/secretion were taken from 200 patients admitted to the gynecology clinic of Mahdieh Hospital (Tehran, Iran) with a clinical presentation suggestive of vulvovaginal candidiasis. The isolates obtained were cultured on Sabouraud dextrose agar and chromogenic agar medium. Candida species were also identified by germ tube formation in serum, chlamydospore production on Corn Meal Agar and carbohydrate absorption using the API 20C-AUX kit. Participants were asked to complete a questionnaire investigating the risk factors associated with candidiasis. An assessment of the different species of recurrent and non-recurrent candidiasis was also made. Descriptive statistics, chi-square test, and t-test were used to analyze the data. A total of 191 isolates were obtained from 175 vaginal specimens. Candida albicans accounted for 67% of the strains including single and mixed infections. The other identified species were Candida glabrata (18.3%), Candida tropicalis (6.8%), Candida krusei (5.8%), Candida parapsilosis (1.6%), and Candida guilliermondii (0.5%) respectively. Mixed infection with two or more species of Candida was seen in 10.3% of patients. The most common mixed cause was the combination of Candida albicans and Candida glabrata. Participants who were sexually active

Candida kuoi sp. nov., an anamorphic species of the Starmerella yeast clade that synthesizes sophorolipids.

PubMed

Kurtzman, Cletus P

2012-09-01

A novel strain of anamorphic yeast, designated strain NRRL Y-27208(T), was isolated from concentrated grape juice in Cape Province, South Africa. Analysis of nuclear large subunit rRNA gene sequences from the D1/D2 domains separated the novel isolate from strains of Starmerella bombicola and Starmerella meliponinorum, as well as from species of the genus Candida that are members of the Starmerella clade. Compared to previously described species, strain NRRL Y-27208(T) is most closely related to S. bombicola but can be separated from this species by its ability to grow on D-ribose and erythritol. Strain NRRL Y-27208(T) produced sophorolipids that have an open chain structure similar to Candida batistae, Candida riodocensis and Candida stellata, which is in contrast to the closed chain sophorolipids produced by S. bombicola and Candida apicola. The analyses showed that NRRL Y-27208(T) (= CBS 7267(T)) represents a novel species distinct from previously described species, for which the name Candida kuoi sp. nov. is proposed.

Approach to the Investigation and Management of Patients With Candida auris, an Emerging Multidrug-Resistant Yeast.

PubMed

Tsay, Sharon; Kallen, Alexander; Jackson, Brendan R; Chiller, Tom M; Vallabhaneni, Snigdha

2018-01-06

Candida auris is an emerging, multidrug-resistant yeast that can spread in healthcare settings. It can cause invasive infections with high mortality and is difficult to identify using traditional yeast identification methods. Candida auris has been reported in more than a dozen countries, and as of August 2017, 112 clinical cases have been reported in the United States. Candida auris can colonize skin and persist in the healthcare environment, allowing for transmission between patients. Prompt investigation and aggressive interventions, including notification to public health agencies, implementation of contact precautions, thorough environmental cleaning and disinfection, infection control assessments, contact tracing and screening of contacts to assess for colonization, and retrospective review of microbiology records and prospective surveillance for cases at laboratories are all needed to limit the spread of C. auris. This review summarizes the current recommended approach to manage cases and control transmission of C. auris in healthcare facilities. Published by Oxford University Press for the Infectious Diseases Society of America 2017. This work is written by (a) US Government employee(s) and is in the public domain in the US.

Candida andamanensis sp. nov., Candida laemsonensis sp. nov. and Candida ranongensis sp. nov., anamorphic yeast species isolated from estuarine waters in a Thai mangrove forest.

PubMed

Am-In, Somjit; Limtong, Savitree; Yongmanitchai, Wichien; Jindamorakot, Sasitorn

2011-02-01

Five strains (RV5(T), RV140, R31(T), RS17 and RS28(T)) representing three novel anamorphic ascomycetous yeast species were isolated by membrane filtration from estuarine waters collected from a mangrove forest in Laem Son National Park, Ranong Province, Thailand, on different occasions. On the basis of morphological, biochemical, physiological and chemotaxonomic characteristics, sequence analysis of the D1/D2 domain of the large-subunit rRNA gene and the internal transcribed spacer region and phylogenetic analysis, three strains were found to represent two novel Candida species. Two strains (RV5(T) and RV140) represented a single novel species, for which the name Candida laemsonensis sp. nov. is proposed. The type strain is RV5(T) (=BCC 35154(T) =NBRC 105873(T) =CBS 11419(T)). Strain R31(T) was assigned to a novel species that was named Candida andamanensis sp. nov. (type strain R31(T) =BCC 25965(T) =NBRC 103862(T) =CBS 10859(T)). On the basis of morphological, biochemical, physiological and chemotaxonomic characteristics, sequence analysis of the D1/D2 domain of the large-subunit rRNA gene and phylogenetic analysis, strains RS17 and RS28(T) represented another novel species of Candida, for which the name Candida ranongensis sp. nov. is proposed. The type strain is RS28(T) (=BCC 25964(T) =NBRC 103861(T) =CBS 10861(T)).

Species Distribution and Susceptibility to Azoles of Vaginal Yeasts Isolated Prostitutes

PubMed Central

Gross, Norma T.; Arias, M. L.; Moraga, M.; Baddasarow, Y.; Jarstrand, C.

2007-01-01

Objective. We investigated the use of miconazole among female prostitutes in Costa Rica as well as the distribution of vaginal yeasts and the susceptibility pattern to azoles of strains obtained from this population. Our intention was to relate a frequent use of miconazole to occurrence of vaginal yeasts resistant to azoles. Methods. Vaginal samples were taken from 277 patients that have previously used azoles. Vaginal swabs were obtained for direct microscopy and culture. Yeast isolates were identified by germ tube test and assimilation pattern. Susceptibility testing was determined using a tablet diffusion method. Results. The number of clinical Candida isolates (one from each patient) was 57 (20.6%). C. albicans was the predominant species (70%), followed by C. parapsilosis (12%), C. tropicalis (5.3%), C. glabrata and C. famata (3.5% each), C. krusei, C. inconspicua and C. guilliermondii (1.7% each). The majority of vaginal Candida isolates were susceptible to ketoconazole (91%), fluconazole (96.5%), and itraconazole (98%). A lower susceptibility of some isolates to miconazole (63%) was observed as compared to the other azoles tested. Moreover, the strains, nonsusceptible to miconazole, were more often obtained from patients that have used this antifungal at least four times within the last year before taking the samples as compared to those with three or less treatments (P<.01). Conclusion. An indiscriminate use of miconazole, such as that observed among female prostitutes in Costa Rica, results in a reduced susceptibility of vaginal yeasts to miconazole but not to other azoles. PMID:18273407

Evolutionary genomics of yeast pathogens in the Saccharomycotina

PubMed Central

Naranjo-Ortíz, Miguel A.; Marcet-Houben, Marina

2016-01-01

Saccharomycotina comprises a diverse group of yeasts that includes numerous species of industrial or clinical relevance. Opportunistic pathogens within this clade are often assigned to the genus Candida but belong to phylogenetically distant lineages that also comprise non-pathogenic species. This indicates that the ability to infect humans has evolved independently several times among Saccharomycotina. Although the mechanisms of infection of the main groups of Candida pathogens are starting to be unveiled, we still lack sufficient understanding of the evolutionary paths that led to a virulent phenotype in each of the pathogenic lineages. Deciphering what genomic changes underlie the evolutionary emergence of a virulence trait will not only aid the discovery of novel virulence mechanisms but it will also provide valuable information to understand how new pathogens emerge, and what clades may pose a future danger. Here we review recent comparative genomics efforts that have revealed possible evolutionary paths to pathogenesis in different lineages, focusing on the main three agents of candidiasis worldwide: Candida albicans, C. parapsilosis and C. glabrata. We will discuss what genomic traits may facilitate the emergence of virulence, and focus on two different genome evolution mechanisms able to generate drastic phenotypic changes and which have been associated to the emergence of virulence: gene family expansion and interspecies hybridization. PMID:27493146

Occurrence and diversity of Candida genus in marine environments

NASA Astrophysics Data System (ADS)

Wang, Lin; Chi, Zhenming; Yue, Lixi; Chi, Zhe; Zhang, Dechao

2008-11-01

A total of 317 yeast isolates from seawater, sediments, mud of salterns, guts of marine fishes and marine algae were obtained. The results of routine identification and molecular characterization showed that six isolates among these marine yeasts belonged to Candida genus as Candida intermedia for YA01a, Candida parapsilosis for 3eA2, Candida quercitrusa for JHSb, Candia rugosa for wl8, Candida zeylanoides for TJY13a, and Candida membranifaciens for W14-3. Isolates YA01a ( Candida intermedia), wl8 ( Candida rugosa), 3eA2 ( Candida parapsilosis), and JHSb ( Candida quercitrusa) were found producing cell-bound lipase, while isolate W14-3 ( Candida membranifaciens) producing riboflavin. These marine yeast Candida spp. seem to have wide potential applications in biotechnology.

Candida ethanolica n. sp.

PubMed

Rybárová, J; Stros, F; Kocková-Kratochvílová, A

1980-01-01

A new yeast, Candida ethanolica, isolated from industrial fodder yeast cultivated on synthetic ethanol as the only source of carbon, originally designated III-5 and III-6, is described. This species differs from all recently accepted Candida species in not assimilating nitrate, not producing urease and not fermenting sugars.

Candida species and other yeasts in the oral cavities of type 2 diabetic patients in Cali, Colombia

PubMed Central

Álvarez, María Inés; de Bernal, Matilde; Collazos, Andrés

2013-01-01

Objective: To determine the prevalence of Candida species and to study factors associated to oral cavity colonization in patients with type 2 diabetes mellitus. Methods: A total of 107 diabetics were classified into controlled and uncontrolled according to glycosylated hemoglobin values. Each patient was assessed for stimulated salivary flow rates, pH, and an oral rinse to search for yeast. The study also determined the state of oral health via Klein and Palmer CPO indexes for permanent dentition, dental plaque by O'Leary, and a periodontal chart. Results: We found yeasts in 74.8% of the patients. A total of 36 of the 52 subjects with controlled diabetes presented yeasts and 44 in the uncontrolled; no significant differences (p = 0.2) were noted among the presence of yeasts and the control of blood glucose. The largest number of isolates corresponded to C. albicans, followed by C. parapsilosis. Uncontrolled individuals presented a significantly higher percentage of yeast different from C. albicans (p = 0.049). Conclusions: We found a high percentage of Candida colonization and uncontrolled individuals had greater diversity of species. The wide range of CFU/mL found both in patients with oral candidiasis, as well as in those without it did not permit distinguishing between colonization and disease. We only found association between isolation of yeasts and the low rate of salivary flow. PMID:24892318

Study of strains of Candida spp. Isolated from catheters in UHC of Oran (Algeria): Identification and antifungal susceptibility.

PubMed

Bendjelloul, M; Boucherit-Otmani, Z; Boucherit, K

2016-09-01

The increasing incidence of Candida spp., and the vital prognosis often compromise for patients with Candida species make urgent the exact knowledge of their distribution worldwide and exhaust action antifungals currently used in clinical. That why we carry out an epidemiological study of Candida species and testing their susceptibility against two antifungals: amphotericin B and caspofungin. Samplings of peripheral venous catheters (PVC) were carried out from during 8months on the services of Internal medicine, Surgery A and Neonatology of Oran's University Hospital Center (UHC). The study of the susceptibility of Candida species to antifungal agents was performed according to the Clinical Laboratory Standards Institute (CLSI 2008). From 300 samples, 25 yeasts were isolated. The rate of colonization PVC was 8.33% by Candida spp. The most isolated strains were Candida parapsilosis with 64% of cases, followed by Candida albicans (12%) then 8% for Candida glabrata and Candida krusei. However, only 4% of isolates were Candida famata or Candida lusitaniae. Furthermore all isolated strains were susceptible to amphotericin B with Minimum Inhibitory Concentrations (MIC) ranging from 0.25 to 1μg/mL. MIC obtained with caspofungin vary from 0.0625 to 2μg/mL for all strains. Moreover, one strain of C. krusei is resistant to caspofungin with a MIC superior to 8μg/mL. All though caspofungin is at least as effective as amphotericin B, it is better tolerated for the treatment of invasive fungal infections. Copyright © 2016. Published by Elsevier Masson SAS.

Candida konsanensis sp. nov., a new yeast species isolated from Jasminum adenophyllum in Thailand with potentially carboxymethyl cellulase-producing capability.

PubMed

Sarawan, Somporn; Mahakhan, Polson; Jindamorakot, Sasitorn; Vichitphan, Kanit; Vichitphan, Sukanda; Sawaengkaew, Jutaporn

2013-08-01

A new yeast species (KKU-FW10) belonging to the Candida genus was isolated from Jasminum adenophyllum in the Plant Genetic Conservation Project under The Royal Initiative of Her Royal Highness Princess Maha Chakri Sirindhorn area, Chulabhorn Dam, Konsan district within Chaiyaphum province in Thailand. The strain was identified via analysis of nucleotide sequences from the D1/D2 domain of 26S ribosomal DNA and based on its morphological, physiological and biochemical characteristics. The sequence obtained from yeast isolate KKU-FW10 was 97 percent identical to that of Candida chanthaburiensis (GenBank accession number AB500861.1), with 506/517 (nucleotides identity/total nucleotides) matching nucleotides, nine substitutions and two gaps being detected. This species belonged to the Candida clade. Regarding morphological characteristics, isolate KKU-FW10 presents cream-colored butyrous colonies, vegetative reproduction through budding and, round cells without filaments or ascospores. The major ubiquinone detected was Q-9. The above results suggest that isolate KKU-FW10 is a new member of the genus Candida, and the name Candida konsanensis is proposed for this yeast. The type strain of the new species is KKU-FW10(T) (= BCC 52588(T), = NBRC 109082(T), = CBS 12666(T)). In addition, this KKU-FW10 could potentially produce 58.24 Units/ml of carboxymethyl cellulase when it was cultured in YP broth containing 1.0 % carboxymethyl cellulose for 24 h.

Candida neustonensis sp. nov., a novel ascomycetous yeast isolated from the sea surface microlayer in Taiwan.

PubMed

Chang, Chin-Feng; Lee, Ching-Fu; Liu, Shiu-Mei

2010-01-01

A new ascomycetous yeast species, Candida neustonensis is proposed in this study based on four strains (SN92(T), SN47, SJ22, SJ25) isolated from sea surface microlayer in Taiwan. These four yeast strains were morphologically, physiologically and phylogenetically identical to each other. No sexual reproduction was observed on 5% malt extract agar, corn meal agar, V8 agar, McClary's acetate agar and potato-dextrose agar. Phylogenetic analysis of the sequences of the D1/D2 domain of the large subunit (LSU) rRNA gene places C. neustonensis as a member of the Pichia guilliermondii clade, it also reveals that the phylogenetically closest relatives of C. neustonensis are C. fukuyamaensis (4.4% divergence), C. xestobii (4.4% divergence) and P. guilliermondii (4.5% divergence). C. neustonensis also is clearly distinguished from other known species in the P. guilliermondii clade based on the results of physiology tests. From these comparison analyses, the following novel yeast species is proposed: Candida neustonensis sp. nov., with strain SN92(T) (= BCRC 23108(T) = JCM 14892(T) = CBS 11061(T)) as the type strain.

Etest and Sensititre YeastOne Susceptibility Testing of Echinocandins against Candida Species from a Single Center in Austria.

PubMed

Aigner, Maria; Erbeznik, Thomas; Gschwentner, Martin; Lass-Flörl, Cornelia

2017-08-01

Candida species were tested for susceptibility to caspofungin, anidulafungin, and micafungin in order to evaluate the roles of Etest and Sensititre YeastOne in antifungal susceptibility testing for daily routines and to survey resistance. A total of 104 Candida species isolates detected from blood cultures were investigated. With EUCAST broth microdilution as the reference method, essential agreement (EA), categorical agreement (CA), very major errors (VME), major errors (ME), and minor (MIN) errors were assessed by reading MICs at 18, 24, and 48 h. By use of EUCAST broth microdilution and species-specific clinical breakpoints (CBPs), echinocandin resistance was not detected during the study period. Using EUCAST CBPs, MIC readings at 24 h for the Etest and Sensititre YeastOne resulted in CA levels of 99% and 93% for anidulafungin and 99% and 97% for micafungin. Using revised CLSI CBPs for caspofungin, CA levels were 92% and 99% for Etest and Sensititre YeastOne. The Etest proved an excellent, easy-to-handle alternative method for testing susceptibility to anidulafungin and micafungin. Due to misclassifications, the Etest is less suitable for testing susceptibility to caspofungin (8% of isolates falsely tested resistant). The CA levels of Sensititre YeastOne were 93% and 97% for anidulafungin and micafungin (24 h) by use of EUCAST CBPs and increased to 100% for both antifungals if CLSI CBPs were applied and to 100% and 99% if Sensititre YeastOne epidemiological cutoff values (ECOFFs) were applied. No one echinocandin could be demonstrated to be superior to another in vitro Since resistance was lacking among our Candida isolates, we cannot derive any recommendation from accurate resistance detection by the Etest and Sensititre YeastOne. Copyright © 2017 American Society for Microbiology.

Yeasts of the genus Candida are the dominant cause of onychomycosis in Libyan women but not men: results of a 2-year surveillance study.

PubMed

Ellabib, M S; Agaj, M; Khalifa, Z; Kavanagh, K

2002-06-01

The reported frequency of recovery of fungi from infected nails varies according to the geographical area. To establish the nature of the causal agents in a sample of the Libyan population presenting with suspected onychomycosis. Samples were taken from the infected fingernails of 648 patients attending the Tripoli Medical Centre. Samples from 500 patients proved positive for fungi following culturing, while 476 were potassium hydroxide and culture positive. Of the culture-positive samples, yeasts of the genus Candida (C. albicans, C. parapsilosis, C. glabrata, C. guillermondii and C. tropicalis) were the dominant cause of this condition in women (417 of 434, 96%) but were responsible for only a minority of cases in men (three of 66, 5%). In contrast, dermatophytes (Trichophyton violaceum, T. rubrum, T. mentagrophytes and Microsporum canis) were responsible for this condition in the majority of cases in men (53 of 66, 80%) but only 3% (15 of 434) of cases in women. The mould Aspergillus nidulans was isolated from the nails of 10 (15%) men and two (0.5%) women. The data obtained in this study reveal an almost total separation of the aetiological agents responsible for onychomycosis based on gender.

Liquid and vapour-phase antifungal activities of essential oils against Candida albicans and non-albicans Candida.

PubMed

Mandras, Narcisa; Nostro, Antonia; Roana, Janira; Scalas, Daniela; Banche, Giuliana; Ghisetti, Valeria; Del Re, Simonetta; Fucale, Giacomo; Cuffini, Anna Maria; Tullio, Vivian

2016-08-30

The management of Candida infections faces many problems, such as a limited number of antifungal drugs, toxicity, resistance of Candida to commonly antifungal drugs, relapse of Candida infections, and the high cost of antifungal drugs. Though azole antifungal agents and derivatives continue to dominate as drugs of choice against Candida infections, there are many available data referring to the anticandidal activity of essential oils. Since we have previous observed a good antimicrobial activity of some essential oils against filamentous fungi, the aim of this study was to extend the research to evaluate the activity of the same oils on Candida albicans, C.glabrata and C.tropicalis clinical strains, as well as the effects of related components. Essential oils selection was based both on ethnomedicinal use and on proved antibacterial and/or antifungal activity of some of these oils. Fluconazole and voriconazole were used as reference drugs. The minimum inhibitory concentration (MIC) and the minimal fungicidal concentration (MFC) of essential oils (thyme red, fennel, clove, pine, sage, lemon balm, and lavender) and their major components were investigated by the broth microdilution method (BM) and the vapour contact assay (VC). Using BM, pine oil showed the best activity against all strains tested, though C.albicans was more susceptible than C.glabrata and C.tropicalis (MIC50-MIC90 = 0.06 %, v/v). On the contrary, sage oil displayed a weak activity (MIC50-MIC90 = 1 %, v/v). Thyme red oil (MIC50-MIC90 ≤ 0.0038 %, v/v for C.albicans and C.tropicalis, and 0.0078- < 0.015 %, v/v for C.glabrata), followed by lemon balm, lavender and sage were the most effective by VC. Carvacrol and thymol showed the highest activity, whereas linalyl acetate showed the lowest activity both by two methods. α-pinene displayed a better activity by BM than VC. Results show a good activity of essential oils, mainly thymus red and pine oils, and their components carvacrol

Antifungal potential of eugenyl acetate against clinical isolates of Candida species.

PubMed

Musthafa, Khadar Syed; Hmoteh, Jutharat; Thamjarungwong, Benjamas; Voravuthikunchai, Supayang Piyawan

2016-10-01

The study evaluated the efficiency of eugenyl acetate (EA), a phytochemical in clove essential oil, against clinical isolates of Candida albicans, Candida parapsilosis, Candida tropicalis, and Candida glabrata. Minimum inhibitory concentrations (MIC) of EA against Candida isolates were in the range between 0.1% and 0.4% (v/v). Spot assay further confirmed the susceptibility of Candida isolates to the compound upon treatment with respective 1 × MIC. Growth profile measured in time kill study evidence that the compound at 1 × MIC and 1/2 × MIC retarded the growth of Candida cells, divulging the fungicidal activity. Light microscopic observation demonstrated that upon treated with EA, rough cell morphology, cell damage, and fragmented patterns were observed in C. albicans, C. parapsilosis, C. tropicalis, and C. glabrata. Furthermore, unusual morphological changes of the organism were observed in scanning electron microscopic study. Therefore, it is validated that the compound could cause cell damage resulting in the cell death of Candida clinical isolates. Eventually, the compound at sub-MIC (0.0125% v/v) significantly inhibited serum-induced germ tube formation by C. albicans. Eugenyl acetate inhibited biofilm forming ability of the organisms as well as reduced the adherence of Candida cells to HaCaT keratinocytes cells. In addition, upon treatment with EA, the phagocytic activity of macrophages was increased significantly against C. albicans (P < 0.05). The results demonstrated the potential of EA as a valuable phytochemical to fight against emerging Candida infections. Copyright © 2016 Elsevier Ltd. All rights reserved.

Scheffersomyces parashehatae f.a., sp. nov., Scheffersomyces xylosifermentans f.a., sp. nov., Candida broadrunensis sp. nov. and Candida manassasensis sp. nov., novel yeasts associated with wood-ingesting insects, and their ecological and biofuel implications.

PubMed

Suh, Sung-Oui; Houseknecht, Janice L; Gujjari, Pushpa; Zhou, Jianlong J

2013-11-01

During a survey of yeasts associated with wood-ingesting insects, 69 strains in the Scheffersomyces clade and related taxa were isolated from passalid and tenebrionid beetles and the decayed wood inhabited by them. The majority of these yeasts was found to be capable of fermenting xylose, and was recognized as Scheffersomyces stipitis or its close relative Scheffersomyces illinoinensis, which are known to be associated with wood-decaying beetles and rotten wood. Yeasts in 'Scheffersomyces' ( = Candida) ergatensis and 'Scheffersomyces' ( = Candida) coipomoensis were also frequently isolated. The remaining six strains were identified as representing four novel species in the genera Scheffersomyces and Candida based on multilocus sequence analyses of nuclear rRNA genes and four protein-coding genes, as well as other taxonomic characteristics. Two xylose-fermenting species, Scheffersomyces parashehatae f.a., sp. nov. (type strain ATCC MYA-4653(T) = CBS 12535(T) = EH045(T); MycoBank MB805440) and Scheffersomyces xylosifermentans f.a., sp. nov. (type strain ATCC MYA-4859(T) = CBS 12540(T) = MY10-052(T); MycoBank MB805441), formed a clade with Scheffersomyces shehatae and related Scheffersomyces species. Interestingly, S. xylosifermentans can survive at 40 °C, which is a rare property among xylose-fermenting yeasts. Candida broadrunensis sp. nov. (type strain ATCC MYA-4650(T) = CBS 11838(T) = EH019(T); MycoBank MB805442) is a sister taxon of C. ergatensis, while Candida manassasensis sp. nov. (type strain ATCC MYA-4652(T) = CBS 12534(T) = EH030(T); MycoBank MB805443) is closely related to Candida palmioleophila in the Candida glaebosa clade. The multilocus DNA sequence comparisons in this study suggest that the genus Scheffersomyces needs to be circumscribed to the species near S. stipitis (type species) and S. shehatae that can be characterized by the ability to ferment xylose.

Wickerhamomyces xylosica sp. nov. and Candida phayaonensis sp. nov., two xylose-assimilating yeast species from soil.

PubMed

Limtong, Savitree; Nitiyon, Sukanya; Kaewwichian, Rungluk; Jindamorakot, Sasitorn; Am-In, Somjit; Yongmanitchai, Wichien

2012-11-01

Two strains (NT29(T) and NT31(T)) of xylose-assimilating yeasts were obtained from soils collected in northern Thailand. On the basis of morphological, biochemical, physiological and chemotaxonomic characteristics, and sequence analysis of the D1/D2 domain of the large subunit rRNA gene and the internal transcribed spacer region, the two strains were found to represent two novel ascomycete yeast species. Strain NT29(T) was assigned to the genus Candida belonging to the Pichia clade as a representative of Candida phayaonensis sp. nov.; the type strain is NT29(T) (=BCC 47634(T)=NBRC 108868(T)=CBS 12319(T)). Strain NT31(T) represented a novel Wickerhamomyces species, which was named Wickerhamomyces xylosica sp. nov.; the type strain is NT31(T) (=BCC 47635(T)=NBRC 108869(T)=CBS 12320(T)).

[The effect of Bacillus intermedius RNAse on the multiplication of Candida tropicalis yeasts].

PubMed

Kupriianova-Ashina, F G; Kolpakov, A I; Egorov, S Iu

1992-01-01

The effect of Bacillus intermedius RNAse on the reproduction of Candida tropicalis and synthesis of the main biopolymers in the yeast cells. It has been found that stimulating action of the enzyme appears at the concentration of 10(-5)-10(-6) mg/ml and does not depend on the physiological state of the sowing culture. The connection between the increase of the ionic penetration and stimulation of the RNA and proteins synthesis in the yeast cells subjected to the RNAse action is shown. The mechanism of chromatine-associated RNA-polymerase activation is suggested to include the alteration of the ionic penetration of cells under the RNAse action.

Evaluation of a Reformulated CHROMagar Candida

PubMed Central

Jabra-Rizk, Mary Ann; Brenner, Troy M.; Romagnoli, Mark; Baqui, A. A. M. A.; Merz, William G.; Falkler, William A.; Meiller, Timothy F.

2001-01-01

CHROMagar Candida is a differential culture medium for the isolation and presumptive identification of clinically important yeasts. Recently the medium was reformulated by Becton Dickinson. This study was designed to evaluate the performance of the new formula of CHROMagar against the original CHROMagar Candida for recovery, growth, and colony color with stock cultures and with direct plating of clinical specimens. A total of 90 stock yeast isolates representing nine yeast species, including Candida dubliniensis, as well as 522 clinical specimens were included in this study. No major differences were noted in growth rate or colony size between the two media for most of the species. However, all 10 Candida albicans isolates evaluated consistently gave a lighter shade of green on the new CHROMagar formulation. In contrast, all 26 C. dubliniensis isolates gave the same typical dark green color on both media. A total of 173 of the 522 clinical specimens were positive for yeast, with eight yeast species recovered. The recovery rates for each species were equivalent on both media, with no consistent species-associated differences in colony size or color. Although both media were comparable in performance, the lighter green colonies of C. albicans isolates on the new CHROMagar made it easier to differentiate between C. albicans and C. dubliniensis isolates. In conclusion, the newly formulated Becton Dickinson CHROMagar Candida medium is as equally suited as a differential medium for the presumptive identification of yeast species and for the detection of multiple yeast species in clinical specimens as the original CHROMagar Candida medium. PMID:11326038

Candida ecuadorensis sp. nov., an ascomycetous yeast species found in two separate regions of Ecuador.

PubMed

James, Stephen A; Carvajal Barriga, Enrique Javier; Barahona, Patricia Portero; Cross, Kathryn; Bond, Christopher J; Roberts, Ian N

2013-01-01

In the course of an on-going study aimed at cataloguing the natural yeast biodiversity found in Ecuador, two strains (CLQCA 13-025 and CLQCA 20-004(T)) were isolated from samples of cow manure and rotten wood collected in two separate provinces of the country (Orellana and Bolívar). These strains were found to represent a novel yeast species based on the sequences of their D1/D2 domain of the large-subunit (LSU) rRNA gene and their physiological characteristics. Phylogenetic analysis based on LSU D1/D2 sequences revealed this novel species to belong to the Metschnikowia clade and to be most closely related to Candida suratensis, a species recently discovered in a mangrove forest in Thailand. The species name of Candida ecuadorensis sp. nov. is proposed to accommodate these strains, with strain CLQCA 20-004(T) (=CBS 12653(T) = NCYC 3782(T)) designated as the type strain.

Ogataea phyllophila sp. nov., Candida chumphonensis sp. nov. and Candida mattranensis sp. nov., three methylotrophic yeast species from phylloplane in Thailand.

PubMed

Koowadjanakul, Nampueng; Jindamorakot, Sasitorn; Yongmanitchai, Wichien; Limtong, Savitree

2011-08-01

Five strains (LN12, LN14(T), LN15(T), LN16 and LN17(T)) representing three novel methylotrophic yeast species were isolated from the external surface of plant leaves by three-consecutive enrichments. On the basis of morphological, biochemical, physiological and chemotaxonomic characteristics, the sequence analysis of the D1/D2 domain of the large subunit (LSU) rRNA gene and the phylogenetic analysis, the five strains were assigned to be one novel Ogataea species and two novel Candida species. Three strains (LN12, LN14(T) and LN16) represent a single novel species of the genus Ogataea, for which the name Ogataea phyllophila sp. nov. is proposed. The type strain is LN14(T) (= BCC 42666(T) = NBRC 107780(T) = CBS 12095(T)). Strain LN15(T) was assigned to be Candida chumphonensis sp. nov. (type strain LN15(T) = BCC 42667(T) = NBRC 107781(T) = CBS 12096(T)). Strain LN17(T) represented another novel species of Candida that was named Candida mattranensis sp. nov. (type strain LN17(T) = BCC 42668(T) = NBRC 107782(T) = CBS 12097(T)).

A paralogue of the phosphomutase-like gene family in Candida glabrata, CgPmu2, gained broad-range phosphatase activity due to a small number of clustered substitutions.

PubMed

Orlando, Kelly A; Iosue, Christine L; Leone, Sarah G; Davies, Danielle L; Wykoff, Dennis D

2015-10-15

Inorganic phosphate is required for a range of cellular processes, such as DNA/RNA synthesis and intracellular signalling. The phosphate starvation-inducible phosphatase activity of Candida glabrata is encoded by the gene CgPMU2 (C. glabrata phosphomutase-like protein). CgPMU2 is part of a three-gene family (∼75% identical) created through gene duplication in the C. glabrata clade; only CgPmu2 is a PHO-regulated broad range acid phosphatase. We identified amino acids that confer broad range phosphatase activity on CgPmu2 by creating fusions of sections of CgPMU2 with CgPMU1, a paralogue with little broad range phosphatase activity. We used site-directed mutagenesis on various fusions to sequentially convert CgPmu1 to CgPmu2. Based on molecular modelling of the Pmu proteins on to a histidine phosphatase crystal structure, clusters of amino acids were found in two distinct regions that were able to confer phosphatase activity. Substitutions in these two regions together conferred broad phosphatase activity on CgPmu1. Interestingly, one change is a histidine adjacent to the active site histidine of CgPmu2 and it exhibits a novel ability to partially replace the conserved active site histidine in CgPmu2. Additionally, a second amino acid change was able to confer nt phosphatase activity to CgPmu1, suggesting single amino acid changes neofunctionalize CgPmu2. © 2015 Authors; published by Portland Press Limited.

Evaluation of chromogenic media and seminested PCR in the identification of Candida species

PubMed Central

Daef, Enas; Moharram, Ahmed; Eldin, Salwa Seif; Elsherbiny, Nahla; Mohammed, Mona

2014-01-01

Identification of Candida cultured from various clinical specimens to the species level is increasingly necessary for clinical laboratories. Although sn PCR identifies the species within hours but its cost-effectiveness is to be considered. So there is always a need for media which help in the isolation and identification at the species level. The study aimed to evaluate the performance of different chromogenic media and to compare the effectiveness of the traditional phenotypic methods vs. seminested polymerase chain reaction (sn PCR) for identification of Candida species. One hundred and twenty seven Candida strains isolated from various clinical specimens were identified by conventional methods, four different chromogenic media and sn PCR. HiCrome Candida Differential and CHROMagar Candida media showed comparably high sensitivities and specificities in the identification of C. albicans, C. tropicalis, C. glabrata and C. krusei. CHROMagar Candida had an extra advantage of identifying all C. parapsilosis isolates. CHROMagar-Pal’s medium identified C. albicans, C. tropicalis and C. krusei with high sensitivities and specificities, but couldn’t identify C. glabrata or C. parapsilosis. It was the only medium that identified C. dubliniensis with a sensitivity and specificity of 100%. Biggy agar showed the least sensitivities and specificities. The overall concordance of the snPCR compared to the conventional tests including CHROMAgar Candida in the identification of Candida species was 97.5%. The use of CHROMAgar Candida medium is an easy and accurate method for presumptive identification of the most commonly encountered Candida spp. PMID:24948942

Inactivation of Candida glabrata by a humid DC argon discharge afterglow: dominant contributions of short-lived aqueous active species

NASA Astrophysics Data System (ADS)

Xiong, Qing; Liu, Hongbin; Lu, Weiping; Chen, Qiang; Xu, Le; Wang, Xia; Zhu, Qunlin; Zeng, Xue; Yi, Ping

2017-05-01

Plasma medicine applications are currently attracting significant interest all over the world. Bactericidal treatments of Candida glabrata cultured in saline suspension are performed in this study by a room-temperature reactive afterglow of a DC-driven argon discharge. Water vapor was added to the discharge to study the inactivation contributions of reactive hydrolytic species including OH and H2O2 transporting along the gas flow to the treated solutions. The inactivation results indicate that the dominant roles in the bactericidal treatments are played by the short-lived aqueous active species, but not the stable species like H2O2aq (aq indicates an aqueous species). Further analysis shows that the ·OHaq radicals play an important role in the inactivation process. The ·OHaq radicals in the suspension are mostly produced from the direct dissolution of the OH species in the reactive afterglow. With the increase of added water vapor content, the ·OHaq production increases and enhances the inactivation efficiency of C. glabrata. Furthermore, it is found that the ambient air diffusion shows essential effects on the bactericidal activity of the remote humid argon discharge. Higher bactericidal effects can be obtained in open-space treatments compared to in a controlled Ar + H2O gas atmosphere. Key active air-byproduct species are believed to be generated in the suspension during the treatments and contributing to the inactivation process. Based on chemical analysis, the peroxynitrous acid ONOOHaq is considered as the key antimicrobial air-byproduct species. These results indicate the important dependence of plasma biomedical effects on the processing environment, which finally relates to the critical contributions of the key reactive species formed therein.

Candida phyllophila sp. nov. and Candida vitiphila sp. nov., two novel yeast species from grape phylloplane in Thailand.

PubMed

Limtong, Savitree; Kaewwichian, Rungluk

2013-01-01

Three strains (K59(T), K60 and K70 (T)) representing two novel yeast species were isolated from the external surface of leaves of different wine grape (Vitis vinifera) plants, which were collected from the Kanchanaburi Research Station (N14°07'15.1″ E099°19'05.6″), Wang Dong Sub-district, Mueang District, Kanchanaburi Province, Thailand, by an enrichment technique. The sequences of the D1/D2 domain of the large subunit (LSU) rRNA gene of two strains (K59(T) and K60) were identical and differed from that of strain K70(T). In terms of pairwise sequence similarity of the D1/D2 domain, the closest species to the three strains was Candida asparagi but with 2.3% nucleotide substitutions for strains K59(T) and K60, and 2.1% nucleotide substitutions for strain K70(T). On the basis of morphological, biochemical, physiological and chemotaxonomic characteristics and the sequence analysis of the D1/D2 domain of the large subunit (LSU) rRNA gene, the three strains were assigned to be two novel Candida species. Two strains (K59(T) and K60) were assigned as Candida phyllophila sp. nov. (type strain K59(T)=BCC 42662(T)=NBRC 107776(T)=CBS 12671(T)). Candida vitiphila sp. nov. is proposed for strain K70(T) (=BCC 42663(T)=NBRC 107777(T)=CBS 12672(T)).

Mitochondrial Telomeres as Molecular Markers for Identification of the Opportunistic Yeast Pathogen Candida parapsilosis

PubMed Central

Nosek, Jozef; Tomáška, L'ubomír; Ryčovská, Adriana; Fukuhara, Hiroshi

2002-01-01

Recent studies have demonstrated that a large number of organisms carry linear mitochondrial DNA molecules possessing specialized telomeric structures at their ends. Based on this specific structural feature of linear mitochondrial genomes, we have developed an approach for identification of the opportunistic yeast pathogen Candida parapsilosis. The strategy for identification of C. parapsilosis strains is based on PCR amplification of specific DNA sequences derived from the mitochondrial telomere region. This assay is complemented by immunodetection of a protein component of mitochondrial telomeres. The results demonstrate that mitochondrial telomeres represent specific molecular markers with potential applications in yeast diagnostics and taxonomy. PMID:11923346

Candida wangnamkhiaoensis sp. nov., an anamorphic yeast species in the Hyphopichia clade isolated in Thailand.

PubMed

Limtong, Savitree; Kaewwichian, Rungluk; Jindamorakot, Sasitorn; Yongmanitchai, Wichien; Nakase, Takashi

2012-06-01

Two strains representing a single novel yeast species were isolated from a flower of Calycoopteris floribunda Lame (SK170(T)) and insect frass (ST-122) collected in Thailand. On the basis of morphological, biochemical, physiological and chemotaxonomic characteristics, and the sequence analysis of the D1/D2 domain of the large subunit rRNA gene and the internal transcribed spacer region, the two strains were assigned as a single novel Candida species in the Hyphopichia clade for which the name Candida wangnamkhiaoensis sp. nov. is proposed. The type strain is SK170(T)=BCC 39604(T)=NBRC 106724(T)=CBS 11695(T)).

[Distribution of Candida species in vaginal specimens and evaluation of CHROMagar Candida medium].

PubMed

Gültekin, Berna; Yazici, Vesile; Aydin, Neriman

2005-07-01

Identification of Candida species is important to guide treatment in vulvovaginal candidiasis which is seen frequently and needs long-term therapy due to recurrence. The aim of this study was to determine the species distribution of Candida isolated from vaginal specimens and evaluation of CHROMagar Candida medium in the laboratory diagnosis. Samples from 80 patients who were clinically diagnosed as vaginitis have been analysed in our laboratory. Colonies appeared on CHROMagar Candida media after 48 hours of incubation at 35 degrees C were evaluated for their colors and characteristics. Candida strains were identified by germ tube test, growth on corn meal Tween 80 agar and when necessary also by API 20 C AUX commercial kit. A total of 84 Candida strains were isolated from 80 patients. Two different Candida species have been isolated from four (5%) of the samples. Among Candida strains isolated, 45 (53.6%) were C. albicans, 29 (34.5%) C. glabrata, 7 (8.3%) C. krusei, and 3 (3.6%) C. kefyr. All of the C. albicans and six of the seven C. krusei isolates have been identified correctly by CHROMagar Candida medium. These results showed that C. albicans is still the most frequently isolated species from vaginal samples. It was concluded that CHROMagar Candida medium is useful for identification of colonies due to frequently seen Candida species and also in differentiation of multiple Candida species grown on the same culture.

Role of tyrosol on Candida albicans, Candida glabrata and Streptococcus mutans biofilms developed on different surfaces.

PubMed

Monteiro, Douglas Roberto; Arias, Laís Salomão; Fernandes, Renan Aparecido; Straioto, Fabiana Gouveia; Barros Barbosa, Débora; Pessan, Juliano Pelim; Delbem, Alberto Carlos Botazzo

2017-02-01

To assess the effect of tyrosol on the production of hydrolytic enzymes (by Candida biofilm cells) and acid (by Streptococcus mutans biofilms), as well as to quantify single and mixed biofilms of these species formed on acrylic resin (AR) and hydroxyapatite (HA). Candida and S. mutans biofilms were formed on AR and HA in the presence of tyrosol during 48 hours. Next, acid proteinase, phospholipase and hemolytic activities of Candida biofilm cells were determined, while acid production by S. mutans biofilms was assessed by pH determination. The effect of tyrosol on mature biofilms (96 hours) was evaluated through quantification of total biomass, metabolic activity, number of colony-forming units and composition of biofilms' extracellular matrix. Data were analyzed by one- and two-way ANOVA, followed by Tukey's and Holm-Sidak's tests (α = 0.05). Treatments with tyrosol were not able to significantly reduce hydrolytic enzymes and acid production by Candida and S. mutans. Tyrosol only significantly reduced the metabolic activity of single biofilms of Candida species. Tyrosol on its own had a limited efficacy against single and mixed-species oral biofilms. Its use as an alternative antimicrobial for topical therapies still demands more investigation.

Comparison of enzymatic activities in different Candida species isolated from women with vulvovaginitis.

PubMed

Fatahinia, M; Halvaeezadeh, M; Rezaei-Matehkolaei, A

2017-06-01

Comparing the activities of secreted enzymes in different fungal species can improve our understanding of their pathogenic role. Secretion of various enzymes by Candida species has been considered for determination of their virulence in different Candida infections including vulvovaginitis. The aim of this study was to determine and compare the activity of secreted enzymes in Candidia strains isolated from women suspected to vulvovaginal candidiasis (VVC) and referred to some health centers in Khuzestan, Southwestern Iran. The vaginal secretion samples were taken by swap from 250 suspected women with symptoms of vulvovaginal candidiasis and cultured on CHROMagar Candida medium. Identification of the isolated Candida from culture positive samples performed by the color of colonies and some standard mycological procedures. Activities of phospholipase, hemolysin-α, hemolysin-β, esterase and proteinase were measured in vitro by standard laboratory protocols. The enzymatic activity index (EAI) was calculated for each enzyme in accordance to relevant protocols. Totally in eighty cases (32%), a Candida strain was isolated which found to be as 52 (65%) Candida albicans; 12 (15%) C. glabrata; 10 (12.5%) C. dubliniensis; 4 (5%) C. krusei, C. tropicalis and C. parapsilosis species (each=1; 1.3%). Among C. albicans strains, 89.1% produced all studied enzymes, while 86% of C. glabrata strains failed to produce proteinase and phospholipase. The EAIs in decreasing order were as hemolysin-β=0.2895, hemolysin-α=0.5420, esterase=0.5753, proteinase=0.7413, and phospholipase=0.7446, respectively. Activity of phospholipase, esterase and proteinase secreted by C. albicans and C. dubliniensis were significantly more than those released by C. glabrata and C. krusei, while 86% of C. glabrata strains did not show esterase activity. On the other hand, the activity rates of hemolysin α and β among all studied isolates were almost similar. In the present study, the prevalence

Detection of Candida species in pregnant Chinese women with a molecular beacon method.

PubMed

Zhai, Yanhong; Liu, Jing; Zhou, Li; Ji, Tongzhen; Meng, Lingxin; Gao, Yang; Liu, Ran; Wang, Xiao; Li, Lin; Lu, Binghuai; Cao, Zheng

2018-04-20

Candida pathogens are commonly found in women and can cause vulvovaginal candidiasis (VVC), whose infection rate is further increased during pregnancy. We aimed to study the Candida prevalence and strain distribution in pregnant Chinese women with a molecular beacon assay. From March 2016 to February 2017, a total of 993 pregnant women attending routine antenatal visits at the Beijing Obstetrics and Gynecology Hospital were enrolled. For Candida detection and identification, a unique molecular beacon assay was presented and compared with a traditional phenotypic method. Antifungal susceptibility was tested with the following agents: 5-flucytosine, amphotericin B, fluconazole, itraconazole and voriconazole. The prevalence of Candida was found to be 21.8 % when using the molecular method and 15.0 % when using the phenotypic method. The distribution of the Candida spp. was listed in order of decreasing prevalence: Candida albicans (79.8 %), Candida glabrata (13.5 %), Candida parapsilosis (3.7 %), Candida krusei (2.2 %) and Candida tropicalis (1.1 %). We found that 90.7 % of the Candida detection results were consistent between the molecular and the phenotypic methods. In the cases where the sequencing analyses for the Candida isolates resulted in inconsistent identification, the molecular method showed higher sensitivity than the phenotypic method (96.0 vs 64.6 %). C. albicans, C. glabrata and C. parapsilosis were essentially susceptible to all five antifungal agents tested, whereas C. tropicalis and C. krusei were susceptible to voriconazole and amphotericin B. By exhibiting good sensitivity and specificity, the molecular assay may offer a fast and accurate Candida screening platform for pregnant women.

Occurrence of yeasts, pseudomonads and enteric bacteria in the oral cavity of patients undergoing head and neck radiotherapy

PubMed Central

Gaetti-Jardim, Elerson; Ciesielski, Francisco Isaak Nicolas; de Sousa, Fátima Regina Nunes; Nwaokorie, Francisca; Schweitzer, Christiane Marie; Avila-Campos, Mario Júlio

2011-01-01

The aim of this study was to evaluate the occurrence of yeasts, pseudomonads and enteric bacteria in the oral cavity of patients undergoing radiotherapy (RT) for treatment of head and neck cancer. Fifty patients receiving RT were examined before, during and 30 days after RT. Saliva, mucosa, and biofilm samples were collected and microorganisms were detected by culture and polymerase chain reaction (PCR). The most prevalent yeasts in patients submitted to RT were Candida albicans, C. tropicalis, C. krusei, C. glabrata and C. parapsilosis. Citrobacter, Enterobacter, Enterococcus, Klebsiella, Proteus, and Pseudomonas were the most frequently cultivated bacteria. Before RT, targeted bacteria were cultivated from 22.2% of edentulous patients and 16.6% of dentate patients; 30 days after RT, these microorganisms were recovered from 77.8% edentulous and 46.8% dentate patients. By PCR, these microorganisms were detected from all edentulous patients, 78.1% of dentate patients. The presence of Gram-negative enteric roads and fungi was particularly frequent in patients presenting mucositis level III or IV. Modifications in the oral environment due to RT treatment seem to facilitate the colonization of oral cavity by members of family Enterobacteriaceae, genera Enterococcus and Candida. PMID:24031721

Anti-Candida activity of Mentha arvensis and Turnera ulmifolia.

PubMed

Santos, Karla K A; Matias, Edinardo F F; Souza, Celestina E S; Tintino, Saulo R; Braga, Maria F B M; Guedes, Glaucia M M; Nogueira, Lavouisier F B; Morais, Edson C; Costa, José G M; Menezes, Irwin R A; Coutinho, Henrique D M

2012-03-01

Candidiasis is the most frequent infection by opportunistic fungi, frequently caused by Candida albicans, Candida tropicalis, Candida parapsilosis, Candida glabrata, and Candida krusei. Mentha arvensis L. is a herbaceous plant that occurs throughout South America and is used as a tea and in the folk medicine. Turnera ulmifolia L. is already known to be of medicinal value. Ethanol extracts from M. arvensis and T. ulmifolia were assayed for antifungal activity against strains of C. albicans, C. tropicalis, and C. krusei. No clinically relevant antifungal activity was demonstrated by the extracts; however, a potentiation effect was observed when the extracts were applied with metronidazole against C. tropicalis. M. arvensis and T. ulmifolia could represent a source of natural products with modifying antifungal activity.

Stress tolerance and biocontrol performance of the yeast antagonist, Candida diversa, change with morphology transition.

PubMed

Li, Guangkun; Chi, Mengshan; Chen, Huizhen; Sui, Yuan; Li, Yan; Liu, Yongsheng; Zhang, Xiaojing; Sun, Zhiqiang; Liu, Guoqing; Wang, Qi; Liu, Jia

2016-02-01

As an eco-friendly management method, biological control of postharvest diseases, utilizing antagonistic yeasts, is a research topic receiving considerable attention. Detailed knowledge on the biology of yeast antagonists is crucial when considering their potential application and development as biocontrol products. Changes in the growth form, such as single-cell to pseudohyphae, have been associated with the mode of action in postharvest biocontrol yeasts. In this study, the antagonistic yeast, Candida diversa, reversibly shifted from a single-cell morphology on yeast peptone dextrose (YPD) medium with 2 % agar to a pseudohyphal morphology on YPD with 0.3 % agar. The tolerance of the pseudohyphal form to heat and oxidative stresses, as well as the biocontrol efficacy against Botrytis cinerea on apple and kiwifruit stored at 25 and 4 °C, was significantly higher as compared to the single-cell form. This study provides new information on the ability of C. diversa to change its morphology and the impact of the morphology shift on stress tolerance and biocontrol performance.

Wickerhamomyces queroliae sp. nov. and Candida jalapaonensis sp. nov., two yeast species isolated from Cerrado ecosystem in North Brazil.

PubMed

Rosa, Carlos A; Morais, Paula B; Lachance, Marc-André; Santos, Renata O; Melo, Weilan G P; Viana, Rodney H O; Bragança, Marcos A L; Pimenta, Raphael S

2009-05-01

Two novel yeast species, Wickerhamomyces queroliae sp. nov. and Candida jalapaonensis sp. nov., were isolated, respectively, from larvae of Anastrepha mucronata (Diptera: Tephritidae) collected from ripe fruit of Peritassa campestris ('Bacupari', Hippocrateaceae) and from flowers of Centropogon cornutus (Campanulaceae) in the Cerrado ecosystem of the state of Tocantins, Brazil. Analysis of the D1/D2 large-subunit rRNA gene sequences placed W. queroliae in the Wickerhamomyces clade near Wickerhamomyces ciferri and Candida silvicultrix. Candida jalapaonensis belongs to the Wickerhamiella clade and is related to Candida drosophilae. The type strain of Wickerhamomyces queroliae is UFMG-05-T200.1(T) (=CBS 10936(T)=NRRL Y-48478(T)) and the type strain of Candida jalapaonensis is UFMG-03-T210(T) (=CBS 10935(T)=NRRL Y-48477(T)).

Characterization of Candida sp. NY7122, a novel pentose-fermenting soil yeast.

PubMed

Watanabe, Itsuki; Ando, Akira; Nakamura, Toshihide

2012-02-01

Yeasts that ferment both hexose and pentose are important for cost-effective ethanol production. We found that the soil yeast strain NY7122 isolated from a blueberry field in Tsukuba (East Japan) could ferment both hexose and pentose (D-xylose and L-arabinose). NY7122 was closely related to Candida subhashii on the basis of the results of molecular identification using the sequence in the D1/D2 domains of 26S rDNA and 5.8S-internal transcribed spacer region. NY7122 produced at least 7.40 and 3.86 g l⁻¹ ethanol from 20 g l⁻¹ D-xylose and L-arabinose within 24 h. NY7122 could produce ethanol from pentose and hexose sugars at 37°C. The highest ethanol productivity of NY7122 was achieved under a low pH condition (pH 3.5). Fermentation of mixed sugars (50 g l⁻¹ glucose, 20 g l⁻¹ D-xylose, and 10 g l⁻¹ L-arabinose) resulted in a maximum ethanol concentration of 27.3 g l⁻¹ for the NY7122 strain versus 25.1 g l⁻¹ for Scheffersomyces stipitis. This is the first study to report that Candida sp. NY7122 from a soil environment could produce ethanol from both D-xylose and L-arabinose.

Yeasts from Scarlet ibises (Eudocimus ruber): A focus on monitoring the antifungal susceptibility of Candida famata and closely related species.

PubMed

Brilhante, Raimunda Sâmia Nogueira; Silva, Aline Lobão da; Monteiro, Frederico Ozanan Barros; Guedes, Glaucia Morgana de Melo; Sales, Jamille Alencar; Oliveira, Jonathas Sales de; Maia Junior, José Erisvaldo; Miranda, Stefânia Araújo; Sidrim, José Júlio Costa; Alencar, Lucas Pereira de; Castelo-Branco, Débora Souza Collares Maia; Cordeiro, Rossana de Aguiar; Pereira Neto, Waldemiro de Aquino; Rocha, Marcos Fábio Gadelha

2017-10-01

This study aimed to identify yeasts from the gastrointestinal tract of scarlet ibises (Eudocimus ruber) and from plant material collected from the environment where they live. Then, the isolates phenotypically identified as Candida famata were submitted to molecular identification of their closely related species and evaluated for their antifungal susceptibility and possible resistance mechanisms to antifungal drugs. Cloacal swabs from 20 scarlet ibises kept in captivity at Mangal das Garças Park (Brazil), pooled stool samples (n = 20) and samples of trunks and hollow of trees (n = 20) obtained from their enclosures were collected. The samples were seeded on Sabouraud agar supplemented with chloramphenicol. The 48 recovered isolates were phenotypically identified as 15 Candida famata, 13 Candida catenulata, 2 Candida intermedia, 1 Candida lusitaniae, 2 Candida guilliermondii, 1 Candida kefyr, 1 Candida amapae, 1 Candida krusei, 8 Trichosporon spp., and 4 Rhodotorula spp. The C. famata isolates were further identified as 3 C. famata, 8 Debaryomyces nepalensis, and 4 C. palmioleophila. All C. famata and C. palmioleophila were susceptible to caspofungin and itraconazole, while one D. nepalensis was resistant to fluconazole and voriconazole. This same isolate and another D. nepalensis had lower amphotericin B susceptibility. The azole resistant strain had an increased efflux of rhodamine 6G and an alteration in the membrane sterol content, demonstrating multifactorial resistance mechanism. Finally, this research shows that scarlet ibises and their environment harbor C. famata and closely related species, including antifungal resistant isolates, emphasizing the need of monitoring the antifungal susceptibility of these yeast species. © The Author 2017. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Comparative Study of Esterase and Hemolytic Activities in Clinically Important Candida Species, Isolated From Oral Cavity of Diabetic and Non-diabetic Individuals.

PubMed

Fatahinia, Mahnaz; Poormohamadi, Farzad; Zarei Mahmoudabadi, Ali

2015-03-01

Diabetes mellitus as a chronic metabolic disease occurs in patients with partial or complete deficiency of insulin secretion or disorder in action of insulin on tissue. The disease is known to provide conditions for overgrowth of Candida species. Candida spp. cause candidiasis by many virulence factors such as esterase, hemolysin and phospholipase. This study aimed to compare esterase and hemolytic activity in various Candida species isolated from oral cavity of diabetic and non-diabetic individuals. Swab samples were taken from 95 patients with diabetes (35 men and 60 women) and 95 normal persons (42 men and 53 women) and cultured on Sabouraud dextrose agar. Identification of isolated yeasts was performed by germ tube test, morphology on CHROMagar Candida medium, corn meal agar and ability to grow at 45°C. Hemolysin activity was evaluated using blood plate assay and esterase activity was determined using the Tween 80 opacity test. Different Candida species were isolated from 57 (60%) diabetic and 24 (25%) non-diabetic individuals. Esterase activity was detected in all Candida isolates. Only 21.6% of C. albicans from patients with diabetes had esterase activity as + 3, while it ranged from + 1 to + 2 in others. Hemolytic activity was determined in C. albicans, C. dubliniensis, C. glabrata and C. krusei as 0.79, 0.58, 0.66 and 0.74, respectively. Hemolytic activity was significantly different in the two groups of diabetics and non-diabetics. Oral carriage of C. albicans in the diabetic group (n = 42; 66.7%) was significantly greater than the control group (n = 16; 57.1%). Esterase activity of C. albicans in diabetic group was higher than non-diabetic group. Although C. albicans remains the most frequently pathogenic yeast for human, but other species are increasing.

Synthetic arylquinuclidine derivatives exhibit antifungal activity against Candida albicans, Candida tropicalis and Candida parapsilopsis.

PubMed

Ishida, Kelly; Fernandes Rodrigues, Juliany Cola; Cammerer, Simon; Urbina, Julio A; Gilbert, Ian; de Souza, Wanderley; Rozental, Sonia

2011-01-21

Sterol biosynthesis is an essential pathway for fungal survival, and is the biochemical target of many antifungal agents. The antifungal drugs most widely used to treated fungal infections are compounds that inhibit cytochrome P450-dependent C14α-demethylase (CYP51), but other enzymes of this pathway, such as squalene synthase (SQS) which catalyses the first committed step in sterol biosynthesis, could be viable targets. The aim of this study was to evaluate the antifungal activity of SQS inhibitors on Candida albicans, Candida tropicalis and Candida parapsilopsis strains. Ten arylquinuclidines that act as SQS inhibitors were tested as antiproliferative agents against three ATCC strains and 54 clinical isolates of Candida albicans, Candida tropicalis and Candida parapsilopsis. Also, the morphological alterations induced in the yeasts by the experimental compounds were evaluated by fluorescence and transmission electron microscopy. The most potent arylquinuclidine derivative (3-[1'-{4'-(benzyloxy)-phenyl}]-quinuclidine-2-ene) (WSP1267) had a MIC50 of 2 μg/ml for all species tested and MIC90 varying from 4 μg/ml to 8 μg/ml. Ultrathin sections of C. albicans treated with 1 μg/ml of WSP1267 showed several ultrastructural alterations, including (a) loss of cell wall integrity, (b) detachment of the plasma membrane from the fungal cell wall, (c) accumulation of small vesicles in the periplasmic region, (d) presence of large electron-dense vacuoles and (e) significantly increased cell size and cell wall thickness. In addition, fluorescence microscopy of cells labelled with Nile Red showed an accumulation of lipid droplets in the cytoplasm of treated yeasts. Nuclear staining with DAPI revealed the appearance of uncommon yeast buds without a nucleus or with two nuclei. Taken together, our data demonstrate that arylquinuclidine derivatives could be useful as lead compounds for the rational synthesis of new antifungal drugs.

Identification of yeast strains isolated from marcha in Sikkim, a microbial starter for amylolytic fermentation.

PubMed

Tsuyoshi, Naoko; Fudou, Ryosuke; Yamanaka, Shigeru; Kozaki, Michio; Tamang, Namrata; Thapa, Saroj; Tamang, Jyoti P

2005-03-15

Marcha or murcha is a traditional amylolytic starter used to produce sweet-sour alcoholic drinks, commonly called jaanr in the Himalayan regions of India, Nepal, Bhutan, and Tibet (China). The aim of this study was to examine the microflora of marcha collected from Sikkim in India, focusing on yeast flora and their roles. Twenty yeast strains were isolated from six samples of marcha and identified by genetic and phenotypic methods. They were first classified into four groups (Group I, II, III, and IV) based on physiological features using an API test. Phylogenetic, morphological, and physiological characterization identified the isolates as Saccharomyces bayanus (Group I); Candida glabrata (Group II); Pichia anomala (Group III); and Saccharomycopsis fibuligera, Saccharomycopsis capsularis, and Pichia burtonii (Group IV). Among them, the Group I, II, and III strains produced ethanol. The isolates of Group IV had high amylolytic activity. Because all marcha samples tested contained both starch degraders and ethanol producers, it was hypothesized that all four groups of yeast (Group I, II, III, and IV) contribute to starch-based alcohol fermentation.

Candida, fluorescent stain (image)

MedlinePlus

... a fluorescent stain of Candida. Candida is a yeast (fungus) that causes mild disease, but in immunocompromised individuals it may cause life-threatening illness. (Image courtesy of the Centers for ...

Epidemiological Cutoff Values for Fluconazole, Itraconazole, Posaconazole, and Voriconazole for Six Candida Species as Determined by the Colorimetric Sensititre YeastOne Method

PubMed Central

Pemán, Javier; Iñiguez, Carmen; Hervás, David; Lopez-Hontangas, Jose L.; Pina-Vaz, Cidalia; Camarena, Juan J.; Campos-Herrero, Isolina; García-García, Inmaculada; García-Tapia, Ana M.; Guna, Remedios; Merino, Paloma; Pérez del Molino, Luisa; Rubio, Carmen; Suárez, Anabel

2013-01-01

In the absence of clinical breakpoints (CBP), epidemiological cutoff values (ECVs) are useful to separate wild-type (WT) isolates (without mechanisms of resistance) from non-WT isolates (those that can harbor some resistance mechanisms), which is the goal of susceptibility tests. Sensititre YeastOne (SYO) is a widely used method to determine susceptibility of Candida spp. to antifungal agents. The CLSI CBP have been established, but not for the SYO method. The ECVs for four azoles, obtained using MIC distributions determined by the SYO method, were calculated via five methods (three statistical methods and based on the MIC50 and modal MIC). Respectively, the median ECVs (in mg/liter) of the five methods for fluconazole, itraconazole, posaconazole, and voriconazole (in parentheses: the percentage of isolates inhibited by MICs equal to or less than the ECVs; the number of isolates tested) were as follows: 2 (94.4%; 944), 0.5 (96.7%; 942), 0.25 (97.6%; 673), and 0.06 (96.7%; 849) for Candida albicans; 4 (86.1%; 642), 0.5 (99.4%; 642), 0.12 (93.9%; 392), and 0.06 (86.9%; 559) for C. parapsilosis; 8 (94.9%; 175), 1 (93.7%; 175), 2 (93.6%; 125), and 0.25 (90.4%; 167) for C. tropicalis; 128 (98.6%; 212), 4 (95.8%; 212), 4 (96.0%; 173), and 2 (98.5; 205) for C. glabrata; 256 (100%; 53), 1 (98.1%; 53), 1 (100%; 33), and 1 (97.9%; 48) for C. krusei; 4 (89.2%; 93), 0.5 (100%; 93), 0.25 (100%; 33), and 0.06 (87.7%; 73) for C. orthopsilosis. All methods included ≥94% of isolates and yielded similar ECVs (within 1 dilution). These ECVs would be suitable for monitoring emergence of isolates with reduced susceptibility by using the SYO method. PMID:23761155

Multicenter surveillance of species distribution and antifungal susceptibilities of Candida bloodstream isolates in South Korea.

PubMed

Jung, Sook-In; Shin, Jong Hee; Song, Jae-Hoon; Peck, Kyong Ran; Lee, Kyungwon; Kim, Mi-Na; Chang, Hyun Ha; Moon, Chi Sook

2010-06-01

Multicenter data on in vitro susceptibility of Candida bloodstream isolates to echinocandin antifungal agents is still lacking in South Korea. We performed a prospective multicenter study to determine the species distribution of Candida bloodstream isolates and their susceptibility to five antifungal agents, including caspofungin and micafungin. A total of 639 isolates were collected from 20 tertiary hospitals between September 2006 and August 2007. Antifungal susceptibilities were determined through the use of the CLSI broth microdilution method M27-A3. The overall species distribution was as follows; Candida albicans (38%), Candida parapsilosis (26%), Candia tropicalis (20%), Candida glabrata (11%), and miscellaneous Candida species (5%). Although C. parapsilosis and miscellaneous Candida species were less susceptible to both echinocandins, all 639 isolates were susceptible to both caspofungin and micafungin (MIC, Candida isolates, with C. glabrata and C. krusei isolates displaying the greatest level of resistance. This is the largest multicenter candidemia study conducted in South Korea and shows that non-C. albicans Candida species, including C. parapsilosis, constitutes over 60% of all Candida species isolates recovered from the bloodstream. In addition, the rates of resistance to all five antifungals, including two echinocandins, are still low among bloodstream isolates in South Korea.

[Export of an invertase by yeast cells (Candida utilis)].

PubMed

Alekseeva, O V; Sabirzianova, T A; Celiakh, I O; Kalebina, T S; Kulaev, I S

2014-01-01

Export and accumulation of various forms of invertase (EC 3.2.1.26) in the cell wall and culture liquid of the yeast Candida utilis was investigated. It was found that the high-molecular-weight CW-form of invertase is present in the cell wall. This form is not exported into the culture liquid, and it is by a third more glycosylated than the previously described exported S-form. It was shown that one of the two liquid forms of invertase exported into the culture-the glycosylated S-form--is retained in the cell wall, while the other one--the nonglycosylated F-form--was not detected in the cell wall. Based on these results, as well as data on the distribution dynamics of the enzyme in the culture liquid and in the cell wall during different growth stages of a yeast culture, we suggested that the nonglycosylated form was exported into the culture liquid via the zone of abnormal cell wall permeability and the glycosylated forms of this enzyme (both exported and nonexported) did not use this pathway (the degree of N-glycosylation is an important factor determining the final localization of the enzyme).

Description of Diutina gen. nov., Diutina siamensis, f.a. sp. nov., and reassignment of Candida catenulata, Candida mesorugosa, Candida neorugosa, Candida pseudorugosa, Candida ranongensis, Candida rugosa and Candida scorzettiae to the genus Diutina.

PubMed

Khunnamwong, Pannida; Lertwattanasakul, Noppon; Jindamorakot, Sasitorn; Limtong, Savitree; Lachance, Marc-André

2015-12-01

Three strains (DMKU-RE28, DMKU-RE43T and DMKU-RE123) of a novel anamorphic yeast species were isolated from rice leaf tissue collected in Thailand. DNA sequence analysis demonstrated that the species forms a sister pair with Candida ranongensis CBS 10861T but differs by 24-30 substitutions in the LSU rRNA gene D1/D2 domains and 30-35 substitutions in the ITS region. A phylogenetic analysis based on both the small and the large rRNA gene subunits confirmed this connection and demonstrated the presence of a clade that also includes Candida catenulata, Candida mesorugosa, Candida neorugosa, Candida pseudorugosa, Candida rugosa and Candida scorzettiae. The clade is not closely affiliated to any known teleomorphic genus, and forms a well-separated lineage from currently recognized genera of the Saccharomycetales. Hence, the genus Diutina gen. nov. is proposed to accommodate members of the clade, including Diutina siamensis f.a. sp. nov. and the preceding seven Candida species. The type strain is DMKU-RE43T ( = CBS 13388T = BCC 61183T = NBRC 109695T).

Echinocandin Resistance in Candida Species Isolates from Liver Transplant Recipients.

PubMed

Prigent, Gwénolé; Aït-Ammar, Nawel; Levesque, Eric; Fekkar, Arnaud; Costa, Jean-Marc; El Anbassi, Sarra; Foulet, Françoise; Duvoux, Christophe; Merle, Jean-Claude; Dannaoui, Eric; Botterel, Françoise

2017-02-01

Liver transplant recipients are at risk of invasive fungal infections, especially candidiasis. Echinocandin is recommended as prophylactic treatment but is increasingly associated with resistance. Our aim was to assess echinocandin drug resistance in Candida spp. isolated from liver transplant recipients treated with this antifungal class. For this, all liver-transplanted patients in a University Hospital (Créteil, France) between January and June of 2013 and 2015 were included. Susceptibilities of Candida isolates to echinocandins were tested by Etest and the EUCAST reference method. Isolates were analyzed by FKS sequencing and genotyped based on microsatellites or multilocus sequence typing (MLST) profiles. Ninety-four patients were included, and 39 patients were colonized or infected and treated with echinocandin. Echinocandin resistance appeared in 3 (8%) of the treated patients within 1 month of treatment. One patient was colonized by resistant Candida glabrata, one by resistant Candida dubliniensis, and one by resistant Candida albicans Molecular analysis found three mutations in FKS2 HS1 (F659S, S663A, and D666E) for C. glabrata and one mutation in FKS1 HS1 (S645P) for C. dubliniensis and C. albicans Susceptible and resistant isolates belonged to the same genotype. To our knowledge, this is the first study on echinocandin resistance in Candida spp. in a liver transplant population. Most resistant isolates were found around/in digestive sites, perhaps due to lower diffusion of echinocandin in these sites. This work documents the risk of emergence of resistance to echinocandin, even after short-term treatment. Copyright © 2017 Prigent et al.

[Evaluation of Vitek 2 for the identification of Candida yeasts].

PubMed

Ochiuzzi, María E; Cataldi, Silvana; Guelfand, Liliana; Maldonado, Ivana; Arechavala, Alicia

2014-01-01

The aim of this investigation was to evaluate the performance of Vitek 2 YST cards (bioMérieux, Inc., Hazelwood, MO, USA) for the identification of yeasts of the genus Candida. A total of 168 isolates were analyzed and the results were compared to those of the API 20 C AUX (24%) o API ID 32 C (76%) kits (bioMérieux, Marcy L'Etoile, France). Each isolate was grown in chromogenic agar and in corn meal agar (Oxoid, UK) to observe its micromorphology. C. albicans and C. dublininesis were identified by additional biochemical and molecular tests. The agreement observed was 98.3%. Only three isolates were incorrectly identified by Vitek 2: one strain of C .tropicalis and one strain of C. krusei were identified as C. parapsilosis by YST while one strain of C. krusei was identified with low discrimination. The average time for obtaining results was 18.25 h. Vitek 2 is a simple, safe and useful system for the identification of significant Candida species. Copyright © 2014 Asociación Colombiana de Psiquiatría. Publicado por Elsevier España. All rights reserved.

Candida kashinagacola sp. nov., C. pseudovanderkliftii sp. nov. and C. vanderkliftii sp. nov., three new yeasts from ambrosia beetle-associated sources.

PubMed

Endoh, Rikiya; Suzuki, Motofumi; Benno, Yoshimi; Futai, Kazuyoshi

2008-10-01

Three new yeast species, Candida kashinagacola (JCM 15019(T) = CBS 10903(T)), C. pseudovanderkliftii (JCM 15025(T) = CBS 10904(T)), and C. vanderkliftii (JCM 15029(T) = CBS 10905(T)) are described on the basis of comparison of nucleotide sequences of large subunit ribosomal DNA D1/D2 region (LSU rDNA D1/D2). The nearest assigned species of the three new species was Candida llanquihuensis. Candida kashinagacola and C. pseudovanderkliftii differed from C. llanquihuensis by 3.8% nucleotide substitution of the region, while C. vanderkliftii did by 4.4%. Three new species differed in a number of physiological and growth characteristics from any previously assigned species and from one another. A phylogenetic tree based on the sequences of LSU rDNA D1/D2 showed that these new species together with Candida sp. ST-246, Candida sp. JW01-7-11-1-4-y2, Candida sp. BG02-7-20-001A-2-1 and C. llanquihuensis form a clade near Ambrosiozyma species. The new species did not assimilate methanol as a sole source of carbon, which supported the monophyly of these non methanol-assimilating species which are closely related to the methylotrophic yeasts. Candida kashinagacola was frequently isolated from the beetle galleries of Platypus quercivorus in three different host trees (Quercus serrata, Q. laurifolia and Castanopsis cuspidata) located in the sourthern part of Kyoto, Japan, thus indicating that this species may be a primary ambrosia fungus of P. quercivorus. On the other hand, C. pseudovanderkliftii and C. vanderkliftii were isolated only from beetle galleries in Q. laurifolia. Candida vanderkliftii was isolated from beetle gallery of Platypus lewisi as well as those of P. quercivorus. Candida pseudovanderkliftii and C. vanderkliftii are assumed to be auxiliary ambrosia fungi of P. quercivorus.

Spectrophotometric evaluation of selenium binding by Saccharomyces cerevisiae ATCC MYA-2200 and Candida utilis ATCC 9950 yeast.

PubMed

Kieliszek, Marek; Błażejak, Stanisław; Płaczek, Maciej

2016-05-01

In this study, the ability of selenium binding the biomas of Saccharomyces cerevisiae ATCC MYA-2200 and Candida utilis ATCC 9950 was investigated. Sodium selenite(IV) salts were added to the experimental media at concentrations of 10, 20, 40, and 60 mg Se(4+) L(-1). In the tested concentration range, one concentration reported a significant reduction in the biomass yield of both yeast strains. Intense growth was observed for C. utilis yeast, which reached the highest biomass yield of 15 gd.w.L(-1) after 24h cultivation in the presence of 10mg Se(4+) L(-1). Based on the use of spectrophotometric method for the determination of selenium content by using Variamine Blue as a chromogenic agent, efficient accumulation of this element in the biomass of the investigated yeast was observed. The highest amount of selenium, that is, 5.64 mg Se(4+)gd.w.(-1), was bound from the environment by S. cerevisiae ATCC MYA-2200 cultured in the presence of 60 mg Se(4+) L(-1) medium 72h Slightly less amount, 5.47 mg Se(4+) gd.w.(-1), was absorbed by C. utilis ATCC 9950 during similar cultural conditions. Based on the results of the biomass yield and the use of selenium from the medium, it can be observed that yeasts of the genus Candida are more efficient in binding this element, and this property finds practical application in the production of selenium-enriched yeast. Copyright © 2016 Elsevier GmbH. All rights reserved.

Candida adriatica sp. nov. and Candida molendinolei sp. nov., two yeast species isolated from olive oil and its by-products.

PubMed

Čadež, Neža; Raspor, Peter; Turchetti, Benedetta; Cardinali, Gianluigi; Ciafardini, Gino; Veneziani, Gianluca; Péter, Gábor

2012-09-01

Thirteen strains isolated from virgin olive oil or its by-products in several Mediterranean countries were found to be phenotypically and genetically divergent from currently recognized yeast species. Sequence analysis of the large subunit (LSU) rDNA D1/D2 domain and internal transcribed spacer regions/5.8S rDNA revealed that the strains represented two novel species described as Candida adriatica sp. nov. (type strain ZIM 2334(T) = CBS 12504(T) = NCAIM Y.02001(T)) and Candida molendinolei sp. nov. (type strain DBVPG 5508(T) = CBS 12508(T) = NCAIM Y.02000(T)). Phylogenetic analysis based on concatenated sequences of the small subunit rRNA gene, the D1/D2 region of the LSU rDNA and the translation elongation factor-1α gene suggested that C. adriatica sp. nov. and C. molendinolei sp. nov. should be placed within the Lindnera and Nakazawaea clades, respectively.

The combined rapid detection and species-level identification of yeasts in simulated blood culture using a colorimetric sensor array.

PubMed

Shrestha, Nabin K; Lim, Sung H; Wilson, Deborah A; SalasVargas, Ana Victoria; Churi, Yair S; Rhodes, Paul A; Mazzone, Peter J; Procop, Gary W

2017-01-01

A colorimetric sensor array (CSA) has been demonstrated to rapidly detect and identify bacteria growing in blood cultures by obtaining a species-specific "fingerprint" of the volatile organic compounds (VOCs) produced during growth. This capability has been demonstrated in prokaryotes, but has not been reported for eukaryotic cells growing in culture. The purpose of this study was to explore if a disposable CSA could differentially identify 7 species of pathogenic yeasts growing in blood culture. Culture trials of whole blood inoculated with a panel of clinically important pathogenic yeasts at four different microorganism loads were performed. Cultures were done in both standard BacT/Alert and CSA-embedded bottles, after adding 10 mL of spiked blood to each bottle. Color changes in the CSA were captured as images by an optical scanner at defined time intervals. The captured images were analyzed to identify the yeast species. Time to detection by the CSA was compared to that in the BacT/Alert system. One hundred sixty-two yeast culture trials were performed, including strains of several species of Candida (Ca. albicans, Ca. glabrata, Ca. parapsilosis, and Ca. tropicalis), Clavispora (synonym Candida) lusitaniae, Pichia kudriavzevii (synonym Candida krusei) and Cryptococcus neoformans, at loads of 8.2 × 105, 8.3 × 103, 8.5 × 101, and 1.7 CFU/mL. In addition, 8 negative trials (no yeast) were conducted. All negative trials were correctly identified as negative, and all positive trials were detected. Colorimetric responses were species-specific and did not vary by inoculum load over the 500000-fold range of loads tested, allowing for accurate species-level identification. The mean sensitivity for species-level identification by CSA was 74% at detection, and increased with time, reaching almost 95% at 4 hours after detection. At an inoculum load of 1.7 CFU/mL, mean time to detection with the CSA was 6.8 hours (17%) less than with the BacT/Alert platform. The CSA

[The evaluation of relationship between the origin of Candida sp. and the ability of biofilm formation on surface of different biomaterials].

PubMed

Ciok-Pater, Emilia; Gospodarek, Eugenia; Prazyńska, Małgorzata; Bogiel, Tomasz

2009-01-01

The increase of fungal infections in recent years is connected with the progress in medicine. The vast usage of biomaterials is an inseparable element of contemporary medicine but it also leads to development of infections. The ability to produce biofilm by those yeasts plays an important role in the pathogenesis of candidiasis. Candida biofilm can form on the surface of plastic materials (silicon, polychloride vinyl, polymethacrylate methyl) used to catheters, drains and dentures production that is why it is a serious problem in case of fungal infections in patients who during the diagnosis and treatment have contact with biomaterials. The aim of the study was the assessment of ability to form biofilm on the surface of different biomaterials (latex silicon, polychloride vinyl, polystyrene, nylon and polymethacrylate methyl). 150 strains of Candida sp. were examined: 85 (56.7%) C. albicans and 65 (43.3%) C. non-albicans. The examined yeasts produced biofilm on the surface of polymethacrylate methyl in 39.3%, latex silicone in 38.7%, polychloride vinyl in 38.0%, polystyrene in 35.3% and nylon in 30.7%. Biofilm was most frequently produced by the strains of C. albicans, C. tropicalis, C. glabrata, C. parapsilosis, C. krusei and C. lusitaniae species.

Two new species of the genus Candida in the Zygoascus clade, Candida lundiana sp. nov. and Candida suthepensis sp. nov., isolated from raw honey in Thailand.

PubMed

Saksinchai, Sujinan; Suzuki, Motofumi; Lumyong, Saisamorn; Ohkuma, Moriya; Chantawannakul, Panuwan

2012-03-01

During a survey of yeasts associated with raw honey collected in Thailand, two strains of the Zygoascus clade were isolated from the Asian cavity-nesting honeybee Apis cerana and the stingless bee Homotrigona fimbriata. Phylogeny based on 26S rDNA D1/D2 sequences placed these yeasts as members of a clade including Candida bituminiphila, Candida patagonica and Candida polysorbophila. The strains of the two novel species, CBS 12271(T) and CBS 12270(T), respectively, could be unquestionably distinguished from their relatives by rDNA sequences and other taxonomic characteristics. Therefore, the novel anamorphic species, Candida lundiana sp. nov. (type strain CBS 12271(T) = JCM 16823(T)) and Candida suthepensis sp. nov. (type strain CBS 12270(T) = JCM 16822(T)) are described.

[Biomass composition of thermotolerant yeasts of the genus Candida under elevated cultivation temperatures].

PubMed

Chistiakova, T I; Dediukhina, E G; Eroshin, V K

1981-01-01

The effect of growth temperature on the content of nucleic acids, the content and composition of protein, and the pool of free amino acids and lipids was studied under the conditions of chemostat cultivation of yeast strains at constant flow rates and pO2. The pool of free amino acids in all of the strains decreased with an increase in the temperature of growth. Changes in the content and composition of other cellular components depending on temperature were determined by individual characteristics of the strains. A linear relationship between the content of biomass components and the temperature of growth was found only in Candida scottii. The temperature of yeast cultivation may be used as a factor regulating the pool of free intracellular amino acids and the fatty acids composition of lipids.

Activity of the aqueous extract of Schinus terebinthifolius Raddi on strains of the Candida genus.

PubMed

Torres, Kátia Andrea de Menezes; Lima, Sônia Maria Rolim Rosa; Ueda, Suely Mitoi Ykko

2016-12-01

Objectives  To evaluate the antifungal susceptibility profile of the aqueous extract of the bark of Schinus terebinthifolius Raddi against the strains of the genus Candida . Methods  By using the disk diffusion method, 50 samples of the genus Candida ( Candida albicans ; Candida krusei ; Candida glabrata ; and Candida tropicalis ), isolated from patients receiving treatment at Hospital Santa Casa de Misericórdia de São Paulo, and 1 American Type Culture Collection (ATCC) sample of each species were tested against: the isolated aqueous extract of the bark of Schinus terebinthifolius Raddi, isolated nystatin, and the association of nystatin and the aqueous extract of Schinus terebinthifolius Raddi. Results  There were no significant differences regarding the different strains of Candida tested. In the presence of the aqueous extract of Schinus terebinthifolius Raddi, no inhibition halo was visible. Isolated nystatin formed an inhibition halo measuring respectively 18.50 mm and 19.50 mm for the Candida albicans species and the others referred to as non- Candida albicans ( Candida krusei ; Candida glabrata ; and Candida tropicalis ). The association of nystatin and the aqueous extract of Schinus terebinthifolius Raddi resulted in inhibition halos measuring 14.25 mm and 16.50 mm respectively. The comparisons of these results are statistically significant ( p  < 0,001). Conclusion  The aqueous extract of Schinus terebinthifolius Raddi showed no antifungal activity in vitro against the strains tested, whereas the association of nystatin and the aqueous extract of Schinus terebinthifolius Raddi caused a decrease in the inhibition halo when compared with isolated nystatin. Thieme-Revinter Publicações Ltda Rio de Janeiro, Brazil.

Susceptibility and molecular characterization of Candida species from patients with vulvovaginitis.

PubMed

Fornari, Gheniffer; Vicente, Vania Aparecida; Gomes, Renata Rodrigues; Muro, Marisol Dominguez; Pinheiro, Rosangela Lameira; Ferrari, Carolina; Herkert, Patricia Fernanda; Takimura, Marcos; Carvalho, Newton Sérgio de; Queiroz-Telles, Flavio

2016-01-01

Vulvovaginal candidiasis affects women of reproductive age, which represents approximately 15-25% of vaginitis cases. The present study aimed to isolate and characterize yeast from the patients irrespective of the presentation of clinical symptoms. The isolates were subjected to in vitro susceptibility profile and characterization by molecular markers, which intended to assess the distribution of species. A total of 40 isolates were obtained and identified through the CHROMagar, API20aux and by ITS and D1/D2 regions sequencing of DNAr gene. Candida albicans strains were genotyped by the ABC system and the isolates were divided into two genotypic groups. The identity of the C. albicans, C. glabrata, C. guilliermondii, C. kefyr and Saccharomyces cerevisiae isolates was confirmed by the multilocus analysis. The strains of Candida, isolated from patients with complications, were found to be resistant to nystatin but sensitive to fluconazole, amphotericin B and ketoconazole, as observed by in vitro sensitivity profile. The isolates from asymptomatic patients, i.e., the colonized group, showed a dose-dependent sensitivity to the anti-fungal agents, fluconazole and amphotericin B. However, the isolates of C. albicans that belong to distinct genotypic groups showed the same in vitro susceptibility profile. Copyright © 2016. Published by Elsevier Editora Ltda.

Characterization of culturable yeast species associating with whole crop corn and total mixed ration silage

PubMed Central

Wang, Huili; Hao, Wei; Ning, Tingting; Zheng, Mingli; Xu, Chuncheng

2018-01-01

Objective This study investigated the association of yeast species with improved aerobic stability of total mixed ration (TMR) silages with prolonged ensiling, and clarified the characteristics of yeast species and their role during aerobic deterioration. Methods Whole crop corn (WCC) silages and TMR silages formulated with WCC were ensiled for 7, 14, 28, and 56 d and used for an aerobic stability test. Predominant yeast species were isolated from different periods and identified by sequencing analyses of the 26S rRNA gene D1/D2 domain. Characteristics (assimilation and tolerance) of the yeast species and their role during aerobic deterioration were investigated. Results In addition to species of Candida glabrata and Pichia kudriavzevii (P. kudriavzevii) previously isolated in WCC and TMR, Pichia manshurica (P. manshurica), Candida ethanolica (C. ethanolica), and Zygosaccharomyces bailii (Z. bailii) isolated at great frequency during deterioration, were capable of assimilating lactic or acetic acid and tolerant to acetic acid and might function more in deteriorating TMR silages at early fermentation (7 d and 14 d). With ensiling prolonged to 28 d, silages became more (p<0.01) stable when exposed to air, coinciding with the inhibition of yeast to below the detection limit. Species of P. manshurica that were predominant in deteriorating WCC silages were not detectable in TMR silages. In addition, the predominant yeast species of Z. bailii in deteriorating TMR silages at later fermentation (28 d and 56 d) were not observed in both WCC and WCC silages. Conclusion The inhibition of yeasts, particularly P. kudriavzevii, probably account for the improved aerobic stability of TMR silages at later fermentation. Fewer species seemed to be involved in aerobic deterioration of silages at later fermentation and Z. bailii was most likely to initiate the aerobic deterioration of TMR silages at later fermentation. The use of WCC in TMR might not influence the predominant yeast

Characterization of culturable yeast species associating with whole crop corn and total mixed ration silage.

PubMed

Wang, Huili; Hao, Wei; Ning, Tingting; Zheng, Mingli; Xu, Chuncheng

2018-02-01

This study investigated the association of yeast species with improved aerobic stability of total mixed ration (TMR) silages with prolonged ensiling, and clarified the characteristics of yeast species and their role during aerobic deterioration. Whole crop corn (WCC) silages and TMR silages formulated with WCC were ensiled for 7, 14, 28, and 56 d and used for an aerobic stability test. Predominant yeast species were isolated from different periods and identified by sequencing analyses of the 26S rRNA gene D1/D2 domain. Characteristics (assimilation and tolerance) of the yeast species and their role during aerobic deterioration were investigated. In addition to species of Candida glabrata and Pichia kudriavzevii ( P. kudriavzevii ) previously isolated in WCC and TMR, Pichia manshurica ( P. manshurica ), Candida ethanolica ( C. ethanolica ), and Zygosaccharomyces bailii ( Z. bailii ) isolated at great frequency during deterioration, were capable of assimilating lactic or acetic acid and tolerant to acetic acid and might function more in deteriorating TMR silages at early fermentation (7 d and 14 d). With ensiling prolonged to 28 d, silages became more (p<0.01) stable when exposed to air, coinciding with the inhibition of yeast to below the detection limit. Species of P. manshurica that were predominant in deteriorating WCC silages were not detectable in TMR silages. In addition, the predominant yeast species of Z. bailii in deteriorating TMR silages at later fermentation (28 d and 56 d) were not observed in both WCC and WCC silages. The inhibition of yeasts, particularly P. kudriavzevii , probably account for the improved aerobic stability of TMR silages at later fermentation. Fewer species seemed to be involved in aerobic deterioration of silages at later fermentation and Z. bailii was most likely to initiate the aerobic deterioration of TMR silages at later fermentation. The use of WCC in TMR might not influence the predominant yeast species during aerobic

Distribution and Drug Susceptibility of Candida spp. Associated With Female Genital Tract Infection, Chongqing, China

PubMed Central

Luo, Xiaodong; Dong, Xiaojing; Pen, Zhi

2015-01-01

Background Vulvovaginal candidiasis is defined as vulvovaginitis associated with vaginal carriage of Candida spp. and is a common problem with a high rate of morbidity. Objectives To investigate the distribution of Candida spp. and evaluate the corresponding antifungal susceptibility in women with genital tract infection in Chongqing, southwestern China. Patients and Methods Samples (n = 2.129) were obtained from female patients with symptoms of genital tract infection. Candida spp. were isolated from the specimens and were identified using a coloration medium and the VITEK 2 Compact automatic microbial identification system. Antifungal susceptibility testing was performed using the ATB FUNGUS drug susceptibility testing system. Results From 2,129 samples, 478 (22.45%) isolates of Candida were isolated, of which 395 (82.64%) were Candida albicans, 39 (8.16%) were C. glabrata, 21 (4.39%) were C. tropicalis, 9 (1.88%) were C. parapsilosis, and 14 (2.93%) were other Candida spp. The resistance of C. albicans, C. glabrata, and C. tropicalis to 5 antifungal drugs (amphotericin B, voriconazole, fluconazole, 5-fluorocytosine, and itraconazole) ranged from 0.5% to 6.4%, 0% to 7.7%, and 0% to 9.6%, respectively. Conclusions Candida albicans was the major pathogen associated with candidiasis of the female genital tract in patients in Chongqing. The results of the antifungal sensitivity of the isolates suggest that it is important for clinicians to administer appropriate antifungals for the treatment of Candida spp. infections. PMID:28138369

Yeast Infection (Vaginal)

MedlinePlus

Yeast infection (vaginal) Overview A vaginal yeast infection is a fungal infection that causes irritation, discharge and intense itchiness ... symptoms Causes The fungus candida causes a vaginal yeast infection. Your vagina naturally contains a balanced mix of yeast, including ...

Next-generation sequencing offers new insights into the resistance of Candida spp. to echinocandins and azoles.

PubMed

Garnaud, Cécile; Botterel, Françoise; Sertour, Natacha; Bougnoux, Marie-Elisabeth; Dannaoui, Eric; Larrat, Sylvie; Hennequin, Christophe; Guinea, Jesus; Cornet, Muriel; Maubon, Danièle

2015-09-01

MDR Candida strains are emerging. Next-generation sequencing (NGS), which enables extensive and deep genome analysis, was used to investigate echinocandin and azole resistance in clinical Candida isolates. Six genes commonly involved in antifungal resistance (ERG11, ERG3, TAC1, CgPDR1, FKS1 and FKS2) were analysed using NGS in 40 Candida isolates (18 Candida albicans, 15 Candida glabrata and 7 Candida parapsilosis). The strategy was validated using strains with known sequences. Then, 8 clinical strains displaying antifungal resistance and 23 sequential isolates collected from 10 patients receiving antifungal therapy were analysed. A total of 391 SNPs were detected, among which 6 coding SNPs were reported for the first time. Novel genetic alterations were detected in both azole and echinocandin resistance genes. A C. glabrata strain, which was resistant to echinocandins but highly susceptible to azoles, harboured an FKS2 S663P mutation plus a novel presumed loss-of-function CgPDR1 mutation. This isolate was from a patient with deep-seated and urinary candidiasis. Another C. glabrata isolate, with an MDR phenotype, carried a new FKS2 S663A mutation and a new putative gain-of-function CgPDR1 mutation (T370I); this isolate showed mutated (80%) and WT (20%) populations and was collected after 75 days of exposure to caspofungin from a patient who underwent complicated abdominal surgery. This study shows that NGS can be used for extensive assessment of genetic mutations involved in antifungal resistance. This type of wide genome approach will become very valuable for detecting mechanisms of resistance in clinical strains subjected to multidrug pressure. © The Author 2015. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Candida profiles and antifungal resistance evolution over a decade in Lebanon.

PubMed

Araj, George Farah; Asmar, Rima George; Avedissian, Aline Zakaria

2015-09-27

Infection with and antifungal resistance of Candida species have been on the rise globally. Relevant data on these pathogens are relatively few in our region, including Lebanon, thus warranting this study. This retrospective study of Candida spp. profiles and their in vitro antifungal susceptibility was based on analysis requests for 186 Candida non-albicans and 61 C. albicans during three periods (2005-2007, 2009-2011, and 2012-2014) over the span of the last 10 years at the American University of Beirut Medical Center (AUBMC), a major tertiary care center in Lebanon. Identification of Candida was done using the API 20C AUX system, and the E-test was used to determine the minimum inhibitory concentrations (MICs) of antifungal agents. Among the 1,300-1,500 Candida isolates recovered yearly, C. albicans rates decreased from 86% in 2005 to around 60% in 2014. Simultaneously, the non-albicans rates increased from 14% in 2005 to around 40% in 2014, revealing 11 species, the most frequent of which were C. tropicalis, C. glabrata, and C. parapsilosis. All these demonstrated high resistance (35%-79%) against itraconazole, but remained uniformly susceptible (100%) to amphotericin B. Though C. albicans and the other species maintained high susceptibility against fluconazole and voriconazole, their MIC90 showed an elevated trend over time, and C. glabrata had the highest resistance rates. The observed rise in resistance among Candida spp. in Lebanon mandates the need for close surveillance and monitoring of antifungal drug resistance for both epidemiologic and treatment purposes.

Isolation of the alkane inducible cytochrome P450 (P450alk) gene from the yeast Candida tropicalis

EPA Science Inventory

The gene for the alkane-inducible cytochrome P450, P450alk, has been isolated from the yeast Candida tropicalis by immunoscreening a λgt11 library. Isolation of the gene has been identified on the basis of its inducibility and partial DNA sequence. Transcripts of this gene were i...

Evaluation of esterase and hemolysin activities of different Candida species isolated from vulvovaginitis cases in Lorestan Province, Iran.

PubMed

Noori, Maryam; Dakhili, Mohammad; Sepahvand, Asghar; Davari, Nader

2017-12-01

Annually affecting millions of women, vulvovaginal candidiasis (VVC) is commonly described by signs and symptoms of vulvovaginal inflammation in the presence of  Candida  species. Today, the detection of the virulence factors plays a major role in the understanding of pathogenesis of candidiasis and helps produce new anticandidial drugs to improve its treatment efficiency. Herein, we aimed to evaluate the esterase and hemolysin activities of the vaginal isolates of Candida and their relationship with the presence of VVC. One-hundred vaginal clinical specimens were randomly collected during September-December 2016. The target population consisted of married women suspected of VVC who presented to health centers in Lorestan Province, Iran. In this study, the esterase activity and hemolysin production of Candida clinical isolates were evaluated using the Tween 80 opacity test and the plate assay, respectively. The most frequent Candida species was C. albicans (66; 66%), followed by C. glabrata (11; 11%) and C. tropicalis (11; 11%). The highest esterase activity was found in C. krusei (75%), followed by C. albicans (68.2%) and C. glabrata (54.5%). The greater part of the positive esterase isolates had Pz 4+ scores. Among the Candida species, C. albicans (22.7 % ), C. glabrata (63.6%), and C. krusei (50%) were found to have the highest rates of alpha, beta, and gamma hemolysin production, respectively. The level of hemolytic activity in 51% of the Candida species was Pz 4+ scores. According to our results, the higher expression rates of both enzymes in C. albicans species relative to those of non-albicans Candidate species can partly reflect the role of the virulence factors involved in C. albicans pathogenicity.

Candida middelhoveniana sp. nov., a new yeast species found on the rhizoplane of organically cultivated sugarcane.

PubMed

Ribeiro, José R de A; Carvalho, Patrícia M B de; Cabral, Anderson de S; Macrae, Andrew; Mendonça-Hagler, Leda C S; Berbara, Ricardo L L; Hagler, Allen N

2011-10-01

A novel yeast species within the Metschnikowiaceae is described based on a strain from the sugarcane (Saccharum sp.) rhizoplane of an organically managed farm in Rio de Janeiro, Brazil. The D1/D2 domain of the large subunit ribosomal RNA gene sequence analysis showed that the closest related species were Candida tsuchiyae with 86.2% and Candida thailandica with 86.7% of sequence identity. All three are anamorphs in the Clavispora opuntiae clade. The name Candida middelhoveniana sp. nov. is proposed to accommodate this highly divergent organism with the type strain Instituto de Microbiologia, Universidade Federal do Rio de Janeiro (IMUFRJ) 51965(T) (=Centraalbureau voor Schimmelcultures (CBS) 12306(T), Universidade Federal de Minas Gerais (UFMG)-70(T), DBVPG 8031(T)) and the GenBank/EMBL/DDBJ accession number for the D1/D2 domain LSU rDNA sequence is FN428871. The Mycobank deposit number is MB 519801.

Enhanced phytate dephosphorylation by using Candida melibiosica yeast-based biofuel cell.

PubMed

Hubenova, Yolina; Georgiev, Danail; Mitov, Mario

2014-10-01

We report for the first time that Candida melibiosica expresses enhanced phytase activity when grown under biofuel cell polarization in a nutrient-poor medium, containing only fructose as a carbohydrate source. Phytase activity during the cultivation under polarization reached up to 25 U per g dry biomass, exceeding with 20 ± 3 % those of the control. A participation of the enzyme in the adaptation processes to the stress conditions is proposed. In addition, steady-state electrical outputs were achieved during biofuel cell operation at continuous polarization under constant load. The obtained results show that C. melibiosica yeast-based biofuel cell could be used for simultaneous electricity generation and phytate bioremediation.

[Fungal diseases of vulva and vagina caused by Candida species].

PubMed

Stock, Ingo

2010-09-01

Fungal diseases of vulva and vagina attributed to Candida species (vulvovaginal candidosis) are the most frequent mycoses of women. They show acute or chronic courses and different disease patterns which can strongly affect the quality of life of the women who are concerned. In general, the most common cause of acute vulvovaginal candidosis is Candida albicans, followed by C. glabrata. In chronic recurrent vulvovaginal candidosis, C. albicans and C. glabrata are often equally distributed. In several cases, treatment requires an antimycotic therapy which refers to the severity and main form of disease as well as to the aetiological agent. Most vulvovaginal candidoses are accessible to the treatment with local and systemic antimycotic agents. Generally, in Germany azoles such as clotrimazole, fluconazole and itraconazole, the polyens nystatin and Amphotericin B and the hydroxypyridone derivative ciclopirox are available for antimycotic therapy of vulvovaginal candidoses. Significance of non-conventional and adjuvant therapeutic approaches is considered to be generally low.

Frequency of Candida albicans in Patients with Funguria.

PubMed

Jamil, Sana; Jamil, Naz; Saad, Uzma; Hafiz, Saleem; Siddiqui, Sualleha

2016-02-01

To determine the frequency of Candida albicansin patients with funguria. Descriptive cross-sectional study. Department of Microbiology, Sindh Institute of Urology and Transplantation, from July to December 2012. Patients’ urine samples with fungus/Candida were included. Candida albicans was identified by the production of tubular structures (germ tubes) on microscopy as per standard procedure followed by inoculation on Chrom agar (Oxoid) and Corn Meal-Tween 80 agar (Oxoid). The identification of other non-albicans Candidaspecies was also done both microscopically and macroscopically as per standard procedure. Out of the 289 isolates, 204 (70.6%) were male patients and 85 (29.4%) were female patients, with 165 (57.1%) from the out-patients and 124 (42.9%) from the in-patients. Five species of Candidawere found to be prevalent including 87 (30.1%) Candida albicans, 176 (60.9%) Candida tropicalis, 14 (4.8%) Candida parapsilosis, 8 (2.8%) Candida glabrata and 4 (1.4%) Candida lusitaniae. Majority of patients with funguria were aged above 50 years (60.2%). In the present study, 30.1% patients with funguria had Candida albicans. The most frequently isolated species was Candida tropicalis(60.9%), followed by other non-albicansCandida. This study has shown the emergence of non-albicans Candidaas a major cause of candiduria.

On the reclassification of species assigned to Candida and other anamorphic ascomycetous yeast genera based on phylogenetic circumscription

USDA-ARS?s Scientific Manuscript database

Multigene phylogenies have been instrumental in revising the classification of ascosporic (teleomorph) yeasts in a natural system based on lines of decent. Although many taxonomic changes have already been implemented for teleomorph taxa, this is not yet the case for the large genus Candida and smal...

Performance of chromogenic media for Candida in rapid presumptive identification of Candida species from clinical materials

PubMed Central

Pravin Charles, M. V.; Kali, Arunava; Joseph, Noyal Mariya

2015-01-01

Background: In perspective of the worldwide increase in a number of immunocompromised patients, the need for identification of Candida species has become a major concern. The development of chromogenic differential media, introduced recently, facilitate rapid speciation. However, it can be employed for routine mycology workup only after an exhaustive evaluation of its benefit and cost effectiveness. This study was undertaken to evaluate the benefit and cost effectiveness of chromogenic media for speciation of Candida clinical isolates. Materials and Methods: Sputum samples of 382 patients were screened for the presence of Candida spp. by Gram stain and culture on sabouraud dextrose agar. Candida species were identified using Gram stain morphology, germ tube formation, cornmeal agar with Tween-80, sugar fermentation tests and morphology on HiCrome Candida differential agar. All the Candida isolates were inoculated on HiCrome Candida agar (HiMedia, Mumbai, India). Results: The sensitivity and specificity of HiCrome agar for identification of Candida albicans were 90% and 96.42%, respectively whereas sensitivity and specificity of carbohydrate fermentation test were 86.67% and 74.07%, respectively. Sensitivity and specificity values of HiCrome agar for detection of C. albicans, Candida parapsilosis and Candida glabrata were above 90%. Conclusions: We found HiCrome agar has high sensitivity and specificity comparable to that of the conventional method. In addition, use of this differential media could significantly cut down the turnaround time as well as cost of sample processing. PMID:26109791

Performance of chromogenic media for Candida in rapid presumptive identification of Candida species from clinical materials.

PubMed

Pravin Charles, M V; Kali, Arunava; Joseph, Noyal Mariya

2015-06-01

In perspective of the worldwide increase in a number of immunocompromised patients, the need for identification of Candida species has become a major concern. The development of chromogenic differential media, introduced recently, facilitate rapid speciation. However, it can be employed for routine mycology workup only after an exhaustive evaluation of its benefit and cost effectiveness. This study was undertaken to evaluate the benefit and cost effectiveness of chromogenic media for speciation of Candida clinical isolates. Sputum samples of 382 patients were screened for the presence of Candida spp. by Gram stain and culture on sabouraud dextrose agar. Candida species were identified using Gram stain morphology, germ tube formation, cornmeal agar with Tween-80, sugar fermentation tests and morphology on HiCrome Candida differential agar. All the Candida isolates were inoculated on HiCrome Candida agar (HiMedia, Mumbai, India). The sensitivity and specificity of HiCrome agar for identification of Candida albicans were 90% and 96.42%, respectively whereas sensitivity and specificity of carbohydrate fermentation test were 86.67% and 74.07%, respectively. Sensitivity and specificity values of HiCrome agar for detection of C. albicans, Candida parapsilosis and Candida glabrata were above 90%. We found HiCrome agar has high sensitivity and specificity comparable to that of the conventional method. In addition, use of this differential media could significantly cut down the turnaround time as well as cost of sample processing.

Effect of salt-tolerant yeast of Candida versatilis and Zygosaccharomyces rouxii on the production of biogenic amines during soy sauce fermentation.

PubMed

Qi, Wei; Hou, Li-Hua; Guo, Hong-Lian; Wang, Chun-Ling; Fan, Zhen-Chuan; Liu, Jin-Fu; Cao, Xiao-Hong

2014-06-01

This study aimed to enhance and improve the quality and safety of soy sauce. In the present work, the change of biogenic amines, such as histamine, tyramine, cadaverine, spermidine, was examined by the treatment of Candida versatilis and Zygosaccharomyces rouxii, and the influence of salt-tolerant yeast on biogenic amines was analysed during the whole fermentation process. The results showed that the content of biogenic amines was elevated after yeast treatment and the content of biogenic amines was influenced by using yeast. The dominating biogenic amine in soy sauce was tyramine. At the end of fermentation, the concentrations of biogenic amines produced by Zygosaccharomyces rouxii and Candida versatilis in the soy mash were 122.71 mg kg(-1) and 69.96 mg kg(-1) . The changes of biogenic amines in high-salt liquid soy mash during fermentation process indicated that a variety of biogenic amines were increased in the fermentation ageing period, which may be due to amino acid decarboxylation to form biogenic amines by yeast decarboxylase. The fermentation period of soy sauce should be longer than 5 months because biogenic amines began to decline after this time period. © 2013 Society of Chemical Industry.

Oral Administration of the Broad-Spectrum Antibiofilm Compound Toremifene Inhibits Candida albicans and Staphylococcus aureus Biofilm Formation In Vivo

PubMed Central

De Cremer, Kaat; Delattin, Nicolas; De Brucker, Katrijn; Peeters, Annelies; Kucharíková, Soña; Gerits, Evelien; Verstraeten, Natalie; Michiels, Jan; Van Dijck, Patrick; Thevissen, Karin

2014-01-01

We here report on the in vitro activity of toremifene to inhibit biofilm formation of different fungal and bacterial pathogens, including Candida albicans, Candida glabrata, Candida dubliniensis, Candida krusei, Pseudomonas aeruginosa, Staphylococcus aureus, and Staphylococcus epidermidis. We validated the in vivo efficacy of orally administered toremifene against C. albicans and S. aureus biofilm formation in a rat subcutaneous catheter model. Combined, our results demonstrate the potential of toremifene as a broad-spectrum oral antibiofilm compound. PMID:25288093

Reduction of Nucleic Acid Content in Candida Yeast Cells by Bovine Pancreatic Ribonuclease A Treatment

PubMed Central

Castro, A. C.; Sinskey, A. J.; Tannenbaum, S. R.

1971-01-01

Yeast as a source of protein for human consumption is limited by its relatively high nucleic acid content. In this study, we developed an enzymatic method of decreasing the nucleic acid content. Candida utilis cells, heat-shocked at 80 C for 30 sec, were treated with bovine pancreatic ribonuclease A. Maximum leakage of nucleic acid was observed when the incubation temperature was between 55 and 65 C, the pH of the system from 6.75 to 8.0, and the enzyme-to-cell ratio 1:10,000 on a weight-by-weight basis. Other factors, such as yeast strain, age of cells, and method of propagation, did not influence the susceptibility of the yeast cells to the action of ribonuclease. Buffers and monovalent cations had no inhibiting effects. Magnesium and calcium ions at concentrations greater than 0.001 m showed marked inhibition on the rate of nucleic acid leakage. This enzymatic method reduced the nucleic acid content of yeast cells from 7.5 to 9.0% to 1.5 to 2.0% with no significant concomitant loss of protein. PMID:5165838

Dimorphic cycle in Candida citri sp. nov., a novel yeast species isolated from rotting fruit in Borneo.

PubMed

Sipiczki, Matthias

2011-03-01

Five dimorphic yeast strains were isolated from rotting lime fruits in Borneo. The sequences of the D1/D2 domains of the 26S rRNA genes, the internal transcribed spacer (ITS) chromosomal regions and the 18S rRNA genes were identical in the isolates and differed from the corresponding sequences of all known yeast species. Based on the sequence differences (12-15% in the D1/D2 domain) from the closest relatives and the different pattern of taxonomic traits, the new isolates are assigned the status of a new species, for which the name Candida citri sp. nov. is proposed. Its type strain is 11-469(T) , which has been deposited in Centralbureau voor Schimmelcultures (Utrecht, the Netherlands) as CBS 11858(T) , Culture Collection of Yeasts (Bratislava, Slovakia) as CCY 29-181-1(T) and the National Collection of Agricultural and Industrial Microorganisms (Budapest, Hungary) as NCAIM Y.01978(T) . MycoBank number: MB 519100. The GenBank accession numbers for nucleotide sequences of its D1/D2 domain, ITS and 18S regions are HM803241, HM803242 and HM803243, respectively. Candida citri produces invasive mycelium composed of true septate hyphae that grow towards nutrient-rich parts of the medium and develop large vacuoles at the nongrowing ends of their cells. The hyphae produce blastoconidia, which can establish satellite yeast colonies in the invaded solid substrate. © 2011 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

Evaluation of esterase and hemolysin activities of different Candida species isolated from vulvovaginitis cases in Lorestan Province, Iran

PubMed Central

Noori, Maryam; Dakhili, Mohammad; Sepahvand, Asghar; Davari, Nader

2017-01-01

Background and Purpose: Annually affecting millions of women, vulvovaginal candidiasis (VVC) is commonly described by signs and symptoms of vulvovaginal inflammation in the presence of Candida species. Today, the detection of the virulence factors plays a major role in the understanding of pathogenesis of candidiasis and helps produce new anticandidial drugs to improve its treatment efficiency. Herein, we aimed to evaluate the esterase and hemolysin activities of the vaginal isolates of Candida and their relationship with the presence of VVC. Materials and Methods: One-hundred vaginal clinical specimens were randomly collected during September-December 2016. The target population consisted of married women suspected of VVC who presented to health centers in Lorestan Province, Iran. In this study, the esterase activity and hemolysin production of Candida clinical isolates were evaluated using the Tween 80 opacity test and the plate assay, respectively. Results: The most frequent Candida species was C. albicans (66; 66%), followed by C. glabrata (11; 11%) and C. tropicalis (11; 11%). The highest esterase activity was found in C. krusei (75%), followed by C. albicans (68.2%) and C. glabrata (54.5%). The greater part of the positive esterase isolates had Pz 4+ scores. Among the Candida species, C. albicans (22.7%), C. glabrata (63.6%), and C. krusei (50%) were found to have the highest rates of alpha, beta, and gamma hemolysin production, respectively. The level of hemolytic activity in 51% of the Candida species was Pz 4+ scores. Conclusion: According to our results, the higher expression rates of both enzymes in C. albicans species relative to those of non-albicans Candidate species can partly reflect the role of the virulence factors involved in C. albicans pathogenicity. PMID:29707672

Comparative molecular dynamics studies of heterozygous open reading frames of DNA polymerase eta (η) in pathogenic yeast Candida albicans

NASA Astrophysics Data System (ADS)

Satpati, Suresh; Manohar, Kodavati; Acharya, Narottam; Dixit, Anshuman

2017-01-01

Genomic instability in Candida albicans is believed to play a crucial role in fungal pathogenesis. DNA polymerases contribute significantly to stability of any genome. Although Candida Genome database predicts presence of S. cerevisiae DNA polymerase orthologs; functional and structural characterizations of Candida DNA polymerases are still unexplored. DNA polymerase eta (Polη) is unique as it promotes efficient bypass of cyclobutane pyrimidine dimers. Interestingly, C. albicans is heterozygous in carrying two Polη genes and the nucleotide substitutions were found only in the ORFs. As allelic differences often result in functional differences of the encoded proteins, comparative analyses of structural models and molecular dynamic simulations were performed to characterize these orthologs of DNA Polη. Overall structures of both the ORFs remain conserved except subtle differences in the palm and PAD domains. The complementation analysis showed that both the ORFs equally suppressed UV sensitivity of yeast rad30 deletion strain. Our study has predicted two novel molecular interactions, a highly conserved molecular tetrad of salt bridges and a series of π-π interactions spanning from thumb to PAD. This study suggests these ORFs as the homologues of yeast Polη, and due to its heterogeneity in C. albicans they may play a significant role in pathogenicity.

Biodecoloration of Reactive Black 5 by the methylotrophic yeast Candida boidinii MM 4035.

PubMed

Martorell, María M; Pajot, Hipólito F; Ahmed, Pablo M; de Figueroa, Lucía I C

2017-03-01

Azo dyes are extensively used in textile dyeing and other industries. Effluents of dying industries are specially colored and could cause severe damage to the environment. The anaerobic treatment of textile dying effluents is nowadays the preferred option, but it could generate carcinogenic aromatic amines. Recently, yeasts have become a promising alternative, combining unicellular growth with oxidative mechanisms. This work reports the characterization of the first methylotrophic yeast with dye decolorizing ability, Candida boidinii MM 4035 and some insights into its decoloration mechanism. The analysis of two selected media revealed a possible two stages mechanism of Reactive Black 5 decoloration. In glucose poor media, decoloration is incomplete and only the first stage proceeds, leading to the accumulation of a purple compound. In media with higher glucose concentrations, the yeast is able to decolorize totally an initial concentration of 200mg/L. The entire process is co-metabolic, being largely dependent on glucose concentration but being able to proceed with several nitrogen sources. Manganese dependent peroxidase but not laccase activity could be detected during decoloration. Aromatic amines do not accumulate in culture media, supporting an oxidative decoloration mechanism of unknown ecophysiological relevance. Copyright © 2016. Published by Elsevier B.V.

[In vitro antifungal resistance in Candida albicans from HIV-infected patients with and without oral candidosis.].

PubMed

Ceballos Salobreña, A; Gaitán Cepeda, L A; Orihuela Cañada, F; Olea Barrionuevo, D; Ceballos García, L; Quindós, G

1999-12-01

The main purpose of this study has been to determine the in vitro antifungal susceptibility of clinical isolates from HIV-infected or AIDS patients, depending on the presence of oral candidosis. The oral cavity of 307 HIV-infected or AIDS patients was examined and an oral swab was cultured on Sabouraud glucose agar and studied by conventional mycological methods. In vitro antifungal susceptibility to amphotericin B, nystatin, fluconazole, itraconazole and ketoconazole was tested by disk diffusion with Neo-Sensitabs tablets (Rosco Diagnostica, Dinamarca). One hundred and thirty five Candida albicans isolates (91 serotype A, 38 serotype B, three C. albicans variety stellatoidea and three untyped isolates), three Candida krusei and two Candida glabrata were obtained. All the isolates were susceptible to nystatin and amphotericin B. However, 7.9% isolates were resistant to fluconazole and 2.9% isolates were resistant to ketoconazole or itraconazole. Nearly all C. krusei and C. glabrata isolates, 31% patients with candidosis and 20% Candida-colonized patients showed decreased susceptibility to azoles. This study shows that polyenes had a great in vitro efficacy against clinical isolates from HIV-infected patients and that in vitro resistance to azoles is not as high as observed in other countries.

In vitro synergism between berberine and miconazole against planktonic and biofilm Candida cultures.

PubMed

Wei, Guo-Xian; Xu, Xin; Wu, Christine D

2011-06-01

To investigate the antimycotic activity of the plant alkaloid berberine (BBR), alone and in combination with antifungal azoles, against planktonic and biofilm Candida cultures. The minimum inhibitory concentrations (MICs) of BBR, miconazole (MCZ), and fluconazole (FLC) towards Candida albicans, Candida glabrata, Candida kefyr, Candida krusei, Candida parapsilosis, and Candida tropicalis were determined by a microdilution method. For C. albicans, the synergistic effects of BBR combined with MCZ or FLC were examined in a paper disc agar diffusion assay and checkerboard microdilution assay. The effect of the BBR/MCZ combination was further investigated in a C. albicans biofilm formation model with a dual-chamber flow cell. The effect on metabolic activity of biofilm cells was established using 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT)/menadione. Berberine inhibited the growth of various Candida species (MICs 0.98-31.25mg/L) in the following order of susceptibility: C. krusei > C. kefyr > C. glabrata > C. tropicalis > C. parapsilosis and C. albicans. Synergism between BBR and MCZ or FLC was observed in the disc diffusion assay as well as in suspension showing an FIC index <0.5 (∑FIC=0.19). Whilst neither BBR (16 mg/L) nor MCZ (0.8 mg/L) alone significantly inhibited biofilm formation of C. albicans, their combination reduced biofilm formation by >91% after 24 h, as established from the reduction in surface area coverage (P<0.01). The BBR/MCZ combination also exhibited synergy against the metabolic activity of pre-formed C. albicans biofilms in polystyrene microtiter plates (∑FIC=0.25). Berberine exhibits synergistic effects with commonly used antimycotic drugs against C. albicans, either in planktonic or in biofilm growth phases. Published by Elsevier Ltd.

Lindane degradation by Candida VITJzN04, a newly isolated yeast strain from contaminated soil: kinetic study, enzyme analysis and biodegradation pathway.

PubMed

Salam, Jaseetha Abdul; Das, Nilanjana

2014-04-01

A new yeast strain was isolated from sugarcane cultivation field which was able to utilize lindane as sole carbon source for growth in mineral medium. The yeast was identified and named as Candida sp. VITJzN04 based on a polyphasic approach using morphological, biochemical and 18S rDNA, D1/D2 and ITS sequence analysis. The isolated yeast strain efficiently degraded 600 mg L⁻¹ of lindane within 6 days in mineral medium under the optimal conditions (pH 7; temperature 30 °C and inoculum dosage 0.06 g L⁻¹) with the least half-life of 1.17 days and degradation constant of 0.588 per day. Lindane degradation was tested with various kinetic models and results revealed that the reaction could be described best by first-order and pseudo first-order models. In addition, involvement of the enzymes viz. dechlorinase, dehalogenase, dichlorohydroquinone reductive dechlorinase, lignin peroxidase and manganese peroxidase was noted during lindane degradation. Addition of H2O2 in the mineral medium showed 32 % enhancement of lindane degradation within 3 days. Based on the metabolites identified by GC-MS and FTIR analysis, sequential process of lindane degradation by Candida VITJzN04 was proposed. To the best of our knowledge, this is the first report of isolation and characterization of lindane-degrading Candida sp. and elucidation of enzyme systems during the degradation process.

Epidemiology, species distribution and outcome of nosocomial Candida spp. bloodstream infection in Shanghai

PubMed Central

2014-01-01

Background Yeasts, mostly Candida, are important causes of bloodstream infections (BSI), responsible for significant mortality and morbidity among hospitalized patients. The epidemiology and species distribution vary from different regions. The goals of this study were to report the current epidemiology of Candida BSI in a Shanghai Teaching Hospital and estimate the impact of appropriate antifungal therapy on the outcome. Methods From January 2008 to December 2012, all consecutive patients who developed Candida BSI at Ruijin University Hospital were enrolled. Underlying diseases, clinical severity, species distribution, antifungal therapy and its impact on the outcome were analyzed. Results A total of 121 episodes of Candida BSI were identified, with an incidence of 0.32 episodes/1,000 admissions (0.21 in 2008 and 0.42 in 2012) The proportion of candidemia caused by non-albicans species (62.8%), including C. parapsilosis (19.8%), C. tropicalis (14.9%), C. glabrata (7.4%), C. guilliermondii (5.8%), C. sake (5.0%) was higher than that of candidemia caused by C. albicans (37.2%). The overall crude 28-day mortality was 28.1% and significantly reduced with appropriate empiric antifungal therapy administered within 5 days (P = 0.006). Advanced age (OR 1.04; P = 0.014), neutropenia < 500/mm3 (OR 17.44; P < 0.001) were independent risk factors for 28-day mortality, while appropriate empiric antifungal therapy (OR 0.369; P = 0.035) was protective against 28-day mortality. Conclusion The epidemiology of candidemia in Shanghai differed from that observed in Western countries. Appropriate empiric antifungal therapy influenced the short-term survival. PMID:24886130

Species Distribution and In Vitro Antifungal Susceptibility of Vulvovaginal Candida Isolates in China

PubMed Central

Wang, Feng-Juan; Zhang, Dai; Liu, Zhao-Hui; Wu, Wen-Xiang; Bai, Hui-Hui; Dong, Han-Yu

2016-01-01

Background: Vulvovaginal candidiasis (VVC) was a common infection associated with lifelong harassment of woman's social and sexual life. The purpose of this study was to describe the species distribution and in vitro antifungal susceptibility of Candida species (Candida spp.) isolated from patients with VVC over 8 years. Methods: Species which isolated from patients with VVC in Peking University First Hospital were identified using chromogenic culture media. Susceptibility to common antifungal agents was determined using agar diffusion method based on CLSI M44-A2 document. SPSS software (version 14.0, Inc., Chicago, IL, USA) was used for statistical analysis, involving statistical description and Chi-square test. Results: The most common strains were Candida (C.) albicans, 80.5% (n = 1775) followed by C. glabrata, 18.1% (n = 400). Nystatin exhibited excellent activity against all species (<4% resistant [R]). Resistance to azole drugs varied among different species. C. albicans: clotrimazole (3.1% R) < fluconazole (16.6% R) < itraconazole (51.5% R) < miconazole (54.0% R); C. glabrata: miconazole (25.6% R) < clotrimazole (50.5% R) < itraconazole (61.9% R) < fluconazole (73.3% R); Candida krusei: clotrimazole (0 R) < fluconazole (57.7% R) < miconazole (73.1% R) < itraconazole (83.3% R). The susceptibility of fluconazole was noticeably decreasing among all species in the study period. Conclusions: Nystatin was the optimal choice for the treatment of VVC at present. The species distribution and in vitro antifungal susceptibility of Candida spp. isolated from patients with VVC had changed over time. PMID:27174323

Antifungal Activity of Lactic Acid Bacteria Strains Isolated from Natural Honey against Pathogenic Candida Species

PubMed Central

Bulgasem, Bulgasem Y.; Lani, Mohd Nizam; Wan Yusoff, Wan Mohtar; Fnaish, Sumaya G.

2016-01-01

The role of lactic acid bacteria (LAB) in honey as antifungal activity has received little attention and their mechanism of inhibitory of fungi is not fully understood. In this study, LAB were isolated from honey samples from Malaysia, Libya, Saudi Arabia, and Yemen. Twenty-five isolates were confirmed LAB by catalase test and Gram staining, and were screened for antifungal activity. Four LAB showed inhibitory activity against Candida spp. using the dual agar overlay method. And they were identified as Lactobacillus plantarum HS isolated from Al-Seder honey, Lactobacillus curvatus HH isolated from Al-Hanon honey, Pediococcus acidilactici HC isolated from Tualang honey and Pediococcus pentosaceus HM isolated from Al-Maray honey by the 16S rDNA sequence. The growth of Candida glabrata ATCC 2001 was strongly inhibited (>15.0 mm) and (10~15 mm) by the isolates of L. curvatus HH and P. pentosaceus HM, respectively. The antifungal activity of the crude supernatant (cell free supernatant, CFS) was evaluated using well diffusion method. The CFS showed high antifungal activity against Candida spp. especially The CFS of L. curvatus HH was significantly (p < 0.05) inhibited growth of C. glabrata ATCC 2001, C. parapsilosis ATCC 2201, and C. tropicalis ATCC 750 with inhibitory zone 22.0, 15.6, and 14.7 mm, respectively. While CFS of P. pentosaceus HM was significantly (p < 0.05) effective against C. krusei, C. glabrata, and C. albicans with inhibition zone 17.2, 16.0, and 13.3 mm, respectively. The results indicated that LAB isolated from honey produced compounds which can be used to inhibit the growth of the pathogenic Candida species. PMID:28154488

Antifungal Activity of Lactic Acid Bacteria Strains Isolated from Natural Honey against Pathogenic Candida Species.

PubMed

Bulgasem, Bulgasem Y; Lani, Mohd Nizam; Hassan, Zaiton; Wan Yusoff, Wan Mohtar; Fnaish, Sumaya G

2016-12-01

The role of lactic acid bacteria (LAB) in honey as antifungal activity has received little attention and their mechanism of inhibitory of fungi is not fully understood. In this study, LAB were isolated from honey samples from Malaysia, Libya, Saudi Arabia, and Yemen. Twenty-five isolates were confirmed LAB by catalase test and Gram staining, and were screened for antifungal activity. Four LAB showed inhibitory activity against Candida spp. using the dual agar overlay method. And they were identified as Lactobacillus plantarum HS isolated from Al-Seder honey, Lactobacillus curvatus HH isolated from Al-Hanon honey, Pediococcus acidilactici HC isolated from Tualang honey and Pediococcus pentosaceus HM isolated from Al-Maray honey by the 16S rDNA sequence. The growth of Candida glabrata ATCC 2001 was strongly inhibited (>15.0 mm) and (10~15 mm) by the isolates of L. curvatus HH and P. pentosaceus HM, respectively. The antifungal activity of the crude supernatant (cell free supernatant, CFS) was evaluated using well diffusion method. The CFS showed high antifungal activity against Candida spp. especially The CFS of L. curvatus HH was significantly ( p < 0.05) inhibited growth of C. glabrata ATCC 2001, C. parapsilosis ATCC 2201, and C. tropicalis ATCC 750 with inhibitory zone 22.0, 15.6, and 14.7 mm, respectively. While CFS of P. pentosaceus HM was significantly ( p < 0.05) effective against C. krusei , C. glabrata , and C. albicans with inhibition zone 17.2, 16.0, and 13.3 mm, respectively. The results indicated that LAB isolated from honey produced compounds which can be used to inhibit the growth of the pathogenic Candida species.

Isolation, selection and evaluation of yeasts for use in fermentation of coffee beans by the wet process.

PubMed

de Melo Pereira, Gilberto Vinícius; Soccol, Vanete Thomaz; Pandey, Ashok; Medeiros, Adriane Bianchi Pedroni; Andrade Lara, João Marcos Rodrigues; Gollo, André Luiz; Soccol, Carlos Ricardo

2014-10-01

During wet processing of coffee, the ripe cherries are pulped, then fermented and dried. This study reports an experimental approach for target identification and selection of indigenous coffee yeasts and their potential use as starter cultures during the fermentation step of wet processing. A total of 144 yeast isolates originating from spontaneously fermenting coffee beans were identified by molecular approaches and screened for their capacity to grow under coffee-associated stress conditions. According to ITS-rRNA gene sequencing, Pichia fermentans and Pichia kluyveri were the most frequent isolates, followed by Candida Candida glabrata, quercitrusa, Saccharomyces sp., Pichia guilliermondii, Pichia caribbica and Hanseniaspora opuntiae. Nine stress-tolerant yeast strains were evaluated for their ability to produce aromatic compounds in a coffee pulp simulation medium and for their pectinolytic activity. P. fermentans YC5.2 produced the highest concentrations of flavor-active ester compounds (viz., ethyl acetate and isoamyl acetate), while Saccharomyces sp. YC9.15 was the best pectinase-producing strain. The potential impact of these selected yeast strains to promote flavor development in coffee beverages was investigated for inoculating coffee beans during wet fermentation trials at laboratory scale. Inoculation of a single culture of P. fermentans YC5.2 and co-culture of P. fermentans YC5.2 and Saccharomyces sp. YC9.15 enhanced significantly the formation of volatile aroma compounds during the fermentation process compared to un-inoculated control. The sensory analysis indicated that the flavor of coffee beverages was influenced by the starter cultures, being rated as having the higher sensory scores for fruity, buttery and fermented aroma. This demonstrates a complementary role of yeasts associated with coffee quality through the synthesis of yeast-specific volatile constituents. The yeast strains P. fermentans YC5.2 and Saccharomyces sp. YC9.15 have a great

Optimization of Culture Medium Enhances Viable Biomass Production and Biocontrol Efficacy of the Antagonistic Yeast, Candida diversa.

PubMed

Liu, Jia; Li, Guangkun; Sui, Yuan

2017-01-01

Viable biomass production is a key determinant of suitability of antagonistic yeasts as potential biocontrol agents. This study investigated the effects of three metal ions (magnesium, ferrous, and zinc) on biomass production and viability of the antagonistic yeast, Candida diversa . Using response surface methodology to optimize medium components, a maximum biomass was obtained, when the collective Mg 2+ , Fe 2+ , and Zn 2+ concentrations were adjusted in a minimal mineral (MM) medium. Compared with the unmodified MM, and three ion-deficient MM media, yeast cells cultured in the three ion-modified MM medium exhibited a lower level of cellular oxidative damage, and a higher level of antioxidant enzyme activity. A biocontrol assay indicated that C. diversa grown in the ion-modified MM exhibited the greatest level of control of gray mold on apple fruit. These results provide new information on culture medium optimization to grow yeast antagonists in order to improve biomass production and biocontrol efficacy.

Optimization of Culture Medium Enhances Viable Biomass Production and Biocontrol Efficacy of the Antagonistic Yeast, Candida diversa

PubMed Central

Liu, Jia; Li, Guangkun; Sui, Yuan

2017-01-01

Viable biomass production is a key determinant of suitability of antagonistic yeasts as potential biocontrol agents. This study investigated the effects of three metal ions (magnesium, ferrous, and zinc) on biomass production and viability of the antagonistic yeast, Candida diversa. Using response surface methodology to optimize medium components, a maximum biomass was obtained, when the collective Mg2+, Fe2+, and Zn2+ concentrations were adjusted in a minimal mineral (MM) medium. Compared with the unmodified MM, and three ion-deficient MM media, yeast cells cultured in the three ion-modified MM medium exhibited a lower level of cellular oxidative damage, and a higher level of antioxidant enzyme activity. A biocontrol assay indicated that C. diversa grown in the ion-modified MM exhibited the greatest level of control of gray mold on apple fruit. These results provide new information on culture medium optimization to grow yeast antagonists in order to improve biomass production and biocontrol efficacy. PMID:29089939

The combined rapid detection and species-level identification of yeasts in simulated blood culture using a colorimetric sensor array

PubMed Central

Lim, Sung H.; Wilson, Deborah A.; SalasVargas, Ana Victoria; Churi, Yair S.; Rhodes, Paul A.; Mazzone, Peter J.; Procop, Gary W.

2017-01-01

Background A colorimetric sensor array (CSA) has been demonstrated to rapidly detect and identify bacteria growing in blood cultures by obtaining a species-specific “fingerprint” of the volatile organic compounds (VOCs) produced during growth. This capability has been demonstrated in prokaryotes, but has not been reported for eukaryotic cells growing in culture. The purpose of this study was to explore if a disposable CSA could differentially identify 7 species of pathogenic yeasts growing in blood culture. Methods Culture trials of whole blood inoculated with a panel of clinically important pathogenic yeasts at four different microorganism loads were performed. Cultures were done in both standard BacT/Alert and CSA-embedded bottles, after adding 10 mL of spiked blood to each bottle. Color changes in the CSA were captured as images by an optical scanner at defined time intervals. The captured images were analyzed to identify the yeast species. Time to detection by the CSA was compared to that in the BacT/Alert system. Results One hundred sixty-two yeast culture trials were performed, including strains of several species of Candida (Ca. albicans, Ca. glabrata, Ca. parapsilosis, and Ca. tropicalis), Clavispora (synonym Candida) lusitaniae, Pichia kudriavzevii (synonym Candida krusei) and Cryptococcus neoformans, at loads of 8.2 × 105, 8.3 × 103, 8.5 × 101, and 1.7 CFU/mL. In addition, 8 negative trials (no yeast) were conducted. All negative trials were correctly identified as negative, and all positive trials were detected. Colorimetric responses were species-specific and did not vary by inoculum load over the 500000-fold range of loads tested, allowing for accurate species-level identification. The mean sensitivity for species-level identification by CSA was 74% at detection, and increased with time, reaching almost 95% at 4 hours after detection. At an inoculum load of 1.7 CFU/mL, mean time to detection with the CSA was 6.8 hours (17%) less than with the

Wickerhamiella pagnoccae sp. nov. and Candida tocantinsensis sp. nov., two ascomycetous yeasts from flower bracts of Heliconia psittacorum (Heliconiaceae).

PubMed

Barbosa, Anne C; Morais, Camila G; Morais, Paula B; Rosa, Luiz H; Pimenta, Raphael S; Lachance, Marc-André; Rosa, Carlos A

2012-02-01

Two novel yeast species were isolated from nectar of flower bracts of Heliconia psittacorum (Heliconiaceae) collected in a Cerrado ecosystem in the state of Tocantins, northern Brazil. Wickerhamiella pagnoccae sp. nov., which is closely related to Candida jalapaonensis, is heterothallic and produces one spheroid ascospore per ascus. Candida tocantinsensis sp. nov. belongs to the Metschnikowiaceae clade and its nearest relative is Candida ubatubensis, but the sequence identity (%) in the D1/D2 domains of the rRNA gene is low. The type strain of W. pagnoccae is UFMG-F18C1(T) ( = CBS 12178(T) = NRRL Y-48735(T)) and the type strain of C. tocantinsensis is UFMG-F16D1(T) ( = CBS 12177(T) = NRRL Y-48734(T)).

Culture media profoundly affect Candida albicans and Candida tropicalis growth, adhesion and biofilm development.

PubMed

Weerasekera, Manjula M; Wijesinghe, Gayan K; Jayarathna, Thilini A; Gunasekara, Chinthika P; Fernando, Neluka; Kottegoda, Nilwala; Samaranayake, Lakshman P

2016-11-01

As there are sparse data on the impact of growth media on the phenomenon of biofilm development for Candida we evaluated the efficacy of three culture media on growth, adhesion and biofilm formation of two pathogenic yeasts, Candida albicans and Candida tropicalis. The planktonic phase yeast growth, either as monocultures or mixed cultures, in sabouraud dextrose broth (SDB), yeast nitrogen base (YNB), and RPMI 1640 was compared, and adhesion as well as biofilm formation were monitored using MTT and crystal violet (CV) assays and scanning electron microscopy. Planktonic cells of C. albicans, C. tropicalis and their 1:1 co-culture showed maximal growth in SDB. C. albicans/C. tropicalis adhesion was significantly facilitated in RPMI 1640 although the YNB elicited the maximum growth for C. tropicalis. Similarly, the biofilm growth was uniformly higher for both species in RPMI 1640, and C. tropicalis was the slower biofilm former in all three media. Scanning electron microscopy images tended to confirm the results of MTT and CV assay. Taken together, our data indicate that researchers should pay heed to the choice of laboratory culture media when comparing relative planktonic/biofilm growth of Candida. There is also a need for standardisation of biofilm development media so as to facilitate cross comparisons between laboratories.

Appearance of colonies of Prototheca on CHROMagar Candida medium.

PubMed

Casal, M; Linares, M J; Solís, F; Rodríguez, F C

1997-01-01

The microorganisms capable of producing opportunist infections include the yeast-like organisms of the genus Candida, and the unicellular algae of the genus Prototheca, which share common features and can, therefore, lead to confusion. Their colonies are almost identical and they grow in the same culture media used routinely in mycology. CHROMagar Candida is a new chromogenic differential isolation medium that facilitates the presumptive differentiation of some of the most clinically important yeast-like organisms. To our knowledge, the use of CHROMagar Candida with Prototheca spp. has not been reported in the literature. This report describes the growth of 151 strains of Prototheca on CHROMagar Candida compared to the growth of a total of 326 well-characterized yeast organisms of the genera Candida, Cryptococcus, Trichosporon, Geotrichum, and Saccharomyces. It is clinically relevant to note that algae of the genus Prototheca (P. wickerhamii, P. zopfii, and P. stagnora) and of the genus Candida parapsilosis produced similar cream-colored colonies on CHROMagar Candida medium. Based on their growth on CHROMagar, a new species of Candida is described, C. zeylanoides, which has blue-green colonies. The colonies of two species of Trichosporon are also differentiated: the blue-green colonies of T. beigelii and the pink colonies of T. capitatum.

Treatment of a critically ill child with disseminated Candida glabrata with a recombinant human antibody specific for fungal heat shock protein 90 and liposomal amphotericin B, caspofungin, and voriconazole.

PubMed

Sutherland, Adam; Ellis, David

2008-07-01

To report a case of fungal sepsis treated prospectively with liposomal amphotericin, caspofungin, and a novel monoclonal antibody specific for candidal heat shock protein 90 (Mycograb, Neutec Pharma, Manchester, UK). Case report. Pediatric intensive care unit in a tertiary care children's hospital. A 7-yr-old male with a history of global developmental delay, epilepsy, and gastroesophageal reflux, who presented to the emergency department with a transdiaphragmatic herniation of bowel and subsequent Candida glabrata infection. Efungumab 1 mg/kg twice daily for 5 days. C-reactive protein fell from 225 mg/L to 99 mg/L, and physiological monitoring parameters improved when Mycograb was used in conjunction with high-dose antifungals. Mycograb therapy was well tolerated, but further experience with this therapy in children is needed.

[Evaluation of mass spectrometry for the identification of clinically interesting yeasts].

PubMed

Galán, Fátima; García-Agudo, Lidia; Guerrero, Inmaculada; Marín, Pilar; García-Tapia, Ana; García-Martos, Pedro; Rodríguez-Iglesias, Manuel

2015-01-01

Identification of yeasts is based on morphological, biochemical and nutritional characteristics, and using molecular methods. Matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry, a new method for the identification of microorganisms, has demonstrated to be very useful. The aim of this study is to evaluate this new method in the identification of yeasts. A total of 600 strains of yeasts isolated from clinical specimens belonging to 9 genera and 43 species were tested. Identification was made by sequencing of the ITS regions of ribosomal DNA, assimilation of carbon compounds (ID 32C), and mass spectrometry on a Microflex spectrometer (Bruker Daltonics GmbH, Germany). A total of 569 strains (94.8%) were identified to species level by ID 32C, and 580 (96.7%) by MALDI-TOF. Concordance between both methods was observed for 553 strains (92.2%), with 100% in clinically relevant species: C. albicans, C. glabrata, C. parapsilosis, C. tropicalis, and almost 100% in C. krusei. MALDI-TOF identified species requiring molecular methods: Candida dubliniensis, C. nivariensis, C. metapsilosis and C. orthopsilosis. Some irregularities were observed in the identification of arthroconidia yeast and basidiomycetes. MALDI-TOF is a rapid, effective and economic method, which enables the identification of most clinically important yeasts and the differentiation of closely related species. It would be desirable to include more species in its database to expand its performance. Copyright © 2014 Elsevier España, S.L.U. y Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

Use of CHROMagar Candida for the presumptive identification of Candida species directly from clinical specimens in resource-limited settings.

PubMed

Nadeem, Sayyada Ghufrana; Hakim, Shazia Tabassum; Kazmi, Shahana Urooj

2010-02-09

Identification of yeast isolated from clinical specimens to the species level has become increasingly important. Ever-increasing numbers of immuno-suppressed patients, a widening range of recognized pathogens, and the discovery of resistance to antifungal drugs are contributing factors to this necessity. A total of 487 yeast strains were studied for the primary isolation and presumptive identification, directly from clinical specimen. Efficacy of CHROMagar Candida has been evaluated with conventional methods including morphology on Corn meal-tween 80 agar and biochemical methods by using API 20 C AUX. The result of this study shows that CHROMagar Candida can easily identify three species of Candida on the basis of colonial color and morphology, and accurately differentiate between them i.e. Candida albicans, Candida tropicalis, and Candida krusei. The specificity and sensitivity of CHROMagar Candida for C. albicans calculated as 99%, for C. tropicalis calculated as 98%, and C. krusei it is 100%. The data presented supports the use of CHROMagar Candida for the rapid identification of Candida species directly from clinical specimens in resource-limited settings, which could be very helpful in developing appropriate therapeutic strategy and management of patients.

Candida vulturna pro tempore sp. nov., a dimorphic yeast species related to the Candida haemulonis species complex isolated from flowers and clinical sample.

PubMed

Sipiczki, Matthias; Tap, Ratna Mohd

2016-10-01

In a taxonomic study of yeasts isolated from flowers in Cagayan de Oro, Mindenao Island, The Philippines, strains were identified as representing Kabatiella microsticta, Metschnikowia koreensis and a hitherto undescribed dimorphic species. Sequences of the D1/D2 domains of the LSU 26S rRNA genes, the internal transcribed spacer (ITS) regions and the SSU 18S rRNA genes were identical in the strains of the last-named group and differed from the corresponding sequences of the type strain of the closest related species, Candida duobushaemulonii, by 4 % (D1/D2), 7 % (ITS) and 1 % (SSU). In an independent study, a strain with D1/D2 and ITS sequences very similar to those of the Philippine strains was isolated in Malaysia from the blood of a patient dying of aspiration pneumonia. Both groups of isolates were moderately sensitive to anidulafungin, caspofungin, fluconazole, itraconazole and voriconazole but resistant to amphotericin B. Molecular phylogenetic analysis of the sequences placed the Philippine and Malaysian isolates close to the Candida haemulonis complex of Candida species. To reflect the geographical location of the sites of sample collection, the novel species name Candida vulturna pro tempore sp. nov. is proposed to accommodate these strains. The type strain is 11-1170T (=CBS 14366T=CCY 094-001-001T=NCAIM-Y02177T) isolated in Cagayan de Oro, The Philippines. Mycobank: MB 817222.

Fluorescence In Situ Hybridization with Peptide Nucleic Acid Probes for Rapid Identification of Candida albicans Directly from Blood Culture Bottles

PubMed Central

Rigby, Susan; Procop, Gary W.; Haase, Gerhard; Wilson, Deborah; Hall, Geraldine; Kurtzman, Cletus; Oliveira, Kenneth; Von Oy, Sabina; Hyldig-Nielsen, Jens J.; Coull, James; Stender, Henrik

2002-01-01

A new fluorescence in situ hybridization (FISH) method that uses peptide nucleic acid (PNA) probes for identification of Candida albicans directly from positive-blood-culture bottles in which yeast was observed by Gram staining (herein referred to as yeast-positive blood culture bottles) is described. The test (the C. albicans PNA FISH method) is based on a fluorescein-labeled PNA probe that targets C. albicans 26S rRNA. The PNA probe is added to smears made directly from the contents of the blood culture bottle and hybridized for 90 min at 55°C. Unhybridized PNA probe is removed by washing of the mixture (30 min), and the smears are examined by fluorescence microscopy. The specificity of the method was confirmed with 23 reference strains representing phylogenetically related yeast species and 148 clinical isolates covering the clinically most significant yeast species, including C. albicans (n = 72), C. dubliniensis (n = 58), C. glabrata (n = 5), C. krusei (n = 2), C. parapsilosis (n = 4), and C. tropicalis (n = 3). The performance of the C. albicans PNA FISH method as a diagnostic test was evaluated with 33 routine and 25 simulated yeast-positive blood culture bottles and showed 100% sensitivity and 100% specificity. It is concluded that this 2.5-h method for the definitive identification of C. albicans directly from yeast-positive blood culture bottles provides important information for optimal antifungal therapy and patient management. PMID:12037084