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1.
Antonie Van Leeuwenhoek ; 113(1): 55-69, 2020 Jan.
Article in English | MEDLINE | ID: mdl-31432290

ABSTRACT

Khanthuli peat swamp forest (PSF) is one of a few fertile peat swamp forests that remain in Thailand. It is composed of primary PSF and some areas which have been degraded to secondary PSF due to drought, wildfires and land conversion, which have resulted in a decrease in peat layers and change in the species of the plant community. In this study, diversity of yeasts in peat from both primary and secondary PSF areas of the Khanthuli PSF was determined based on culture-dependent approaches, using dilution plate and enrichment techniques. A total of 66 yeast isolates were identified by the analysis of sequence similarity of the D1/D2 region of the large subunit rRNA gene or the combined analysis of sequence of the D1/D2 region and internal transcribed spacer region and confirmed by phylogenetic analysis of the D1/D2 region to belong to 22 known yeast species and six potential new species in the genera Candida (Kurtzmaniella, Lodderomyces, Ogataea, Pichia and Yamadazyma clades), Clavispora, Cyberlindnera, Galactomyces, Hanseniaspora, Metschnikowia, Saturnispora, Schwanniomyces, Cryptotrichosporon, Pichia, Curvibasidium, Papiliotrema, Rhodotorula, and Saitozyma. The most prevalent yeasts in the primary PSF were Cyberlindnera subsufficiens and Galactomyces candidus, while Saitozyma podzolica was the most frequently found in peat from the secondary PSF. Common yeast species in both, primary and secondary PSF, were Cy. subsufficiens, G. candidus and Rhodotorula mucilaginosa.


Subject(s)
Forests , Soil Microbiology , Soil , Wetlands , Basidiomycota/classification , Basidiomycota/genetics , Biodiversity , Candida/classification , Candida/genetics , Candida glabrata/classification , Candida glabrata/genetics , Candida glabrata/immunology , Candidiasis/classification , Candidiasis/genetics , Cryptococcus/classification , Cryptococcus/genetics , DNA, Fungal/genetics , Metschnikowia/classification , Metschnikowia/genetics , Pichia/classification , Pichia/genetics , Saccharomyces/classification , Saccharomyces/genetics , Thailand , Torulaspora/classification , Torulaspora/genetics , Yarrowia/classification , Yarrowia/genetics
2.
Curr Genet ; 65(1): 93-98, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30027485

ABSTRACT

Candida glabrata is an opportunistic yeast pathogen, whose incidence has increased over the last decades. Despite its genus name, this species is actually more closely related to the budding yeast Saccharomyces cerevisiae than to other Candida pathogens, such as Candida albicans. Hence, C. glabrata and C. albicans must have acquired the ability to infect humans independently, which is reflected in the use of different mechanism for virulence, and survival in the host. Yet, research on C. glabrata suffers from assumptions carried over from the more studied C. albicans. Regarding the adaptation of C. glabrata to the human host, the prejudice was that, just as C. albicans, C. glabrata is a natural human commensal that turns deadly when immune defenses weaken. It was also considered asexual, as no one has observed mating, diploids, or spores, despite great efforts. However, the recent analysis of whole genomes from globally distributed C. glabrata isolates have shaken these assumptions. C. glabrata seems to be only secondarily associated to humans, as indicated by a lack of co-evolution with its host, and genomic footprints of recombination shows compelling evidence that this yeast is able to have sex. Here, we discuss the implications of this and other recent findings and highlight the new questions opened by this change in paradigm.


Subject(s)
Candida glabrata/genetics , Genes, Mating Type, Fungal/genetics , Genome, Fungal/genetics , Genomics/methods , Candida glabrata/classification , Candida glabrata/physiology , Candidiasis/microbiology , Host-Pathogen Interactions , Humans , Phylogeny , Reproduction/genetics , Symbiosis
3.
Med Mycol ; 57(7): 914-917, 2019 Oct 01.
Article in English | MEDLINE | ID: mdl-30597052

ABSTRACT

Candida glabrata is a genetically diverse human pathogenic yeast, whose subpopulations have been documented to vary geographically. Here, we report MLST genotypes and antifungal drug susceptibility of C. glabrata isolates from Africa. Among 47 mostly urogenital isolates, we found 13 sequence types, amounting to a 27% genetic population difference. More than half of the isolates were of novel sequence types. ST18 was most predominant and had reduced susceptibility to fluconazole. There was clear segregation of STs between urine and vaginal specimen. In Tanzania, the C. glabrata population is genetically diverse, and divergent from those seen in other countries.


Subject(s)
Antifungal Agents/pharmacology , Candida glabrata/drug effects , Candida glabrata/genetics , Candidiasis/microbiology , Genetic Variation , Tertiary Care Centers , Africa , Alleles , Bacterial Typing Techniques , Candida glabrata/classification , Candidiasis/blood , Genotype , Humans , Microbial Sensitivity Tests , Multilocus Sequence Typing , Tanzania
4.
Med Mycol ; 56(2): 207-215, 2018 Feb 01.
Article in English | MEDLINE | ID: mdl-28482076

ABSTRACT

Candida glabrata is often the second most common causative agent for candidiasis following Candida albicans. Despite the importance of C. glabrata infections, few epidemiological studies have been conducted on this issue. The goal of this study was genotyping of clinical isolates of C. glabrata by multilocus sequence typing (MLST) technique for determination of the endemic prevalent genotypes and any association between isolation source and drug resistance. A total of 50 C. glabrata clinical isolates from Iran were analyzed by MLST and tested for in-vitro susceptibilities to amphotericin-B, caspofungin, fluconazole, and voriconazole according to the Clinical Laboratory Standards Institute (CLSI) M27-A4 document guidelines. Among these isolates, 16 distinct STs were identified, indicating a discriminatory power index of 0.9029. The three major sequence types (STs) were ST-59, ST-74, and ST-7 with 10, 8, and 7 isolates, respectively. Furthermore, a total of 11 new sequences were found, to which no allele numbers were assigned in the MLST database. All the isolates were susceptible to amphotericin B and caspofungin. Fluconazole resistance was shown in four isolates. Also, a sole isolate was voriconazole resistant. This study shows that the population structure of C. glabrata in Iran consists of groups closely related to the global database as well as to some new clonal clusters and STs. Regarding the high prevalence of 11 new sequences found in this study, it can be concluded that, these new alleles are among the endemic genotypes of Iran. The genotypes or STs were independent of drug susceptibility and anatomic sources.


Subject(s)
Antifungal Agents/pharmacology , Candida glabrata/drug effects , Candida glabrata/genetics , Candidiasis/epidemiology , Candidiasis/microbiology , Drug Resistance, Fungal , Amino Acid Substitution , Antifungal Agents/toxicity , Base Sequence , Candida glabrata/classification , Candida glabrata/isolation & purification , Candidiasis/drug therapy , DNA, Fungal/genetics , Epidemiologic Studies , Genetic Variation , Genotype , Humans , Iran/epidemiology , Microbial Sensitivity Tests , Microbial Viability/drug effects , Phylogeny , Prevalence , Sequence Alignment
5.
J Clin Microbiol ; 54(4): 1042-50, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26842706

ABSTRACT

The opportunistic yeast Candida glabratais increasingly refractory to antifungal treatment or prophylaxis and relatedly is increasingly implicated in health care-associated infections. To elucidate the epidemiology of these infections, strain typing is required. Sequence-based typing provides multiple advantages over length-based methods, such as pulsed-field gel electrophoresis (PFGE); however, conventional multilocus sequence typing (targeting 6 conserved loci) and whole-genome sequencing are impractical for routine use. A commercial sequence-based typing service for C. glabratathat targets polymorphic tandem repeat-containing loci has recently been developed. These CgMT-J and CgMT-M services were evaluated with 56 epidemiologically unrelated isolates, 4 to 7 fluconazole-susceptible or fluconazole-resistant isolates from each of 5 center A patients, 5 matched pairs of fluconazole-susceptible/resistant isolates from center B patients, and 7 isolates from a center C patient who responded to then failed caspofungin therapy. CgMT-J and CgMT-M generated congruent results, resolving isolates into 24 and 20 alleles, respectively. Isolates from all but one of the center A patients shared the same otherwise rare alleles, suggesting nosocomial transmission. Unexpectedly, Pdr1 sequencing showed that resistance arose independently in each patient. Similarly, most isolates from center B also clustered together; however, this may reflect a dominant clone since their alleles were shared by multiple unrelated isolates. Although distinguishable by their echinocandin susceptibilities, all isolates from the center C patient shared alleles, in agreement with the previously reported relatedness of these isolates based on PFGE. Finally, we show how phylogenetic clusters can be used to provide surrogate parents to analyze the mutational basis for antifungal resistance.


Subject(s)
Candida glabrata/classification , Candida glabrata/genetics , Candidiasis/epidemiology , Candidiasis/microbiology , Multilocus Sequence Typing/methods , Mycological Typing Techniques/methods , Candida glabrata/isolation & purification , Cluster Analysis , Genetic Loci , Genetic Variation , Genotype , Humans , Molecular Epidemiology/methods
6.
Eur J Clin Microbiol Infect Dis ; 35(6): 885-92, 2016 Jun.
Article in English | MEDLINE | ID: mdl-26946511

ABSTRACT

This study aimed to elucidate the genetic relatedness and epidemiology of 127 clinical and environmental Candida glabrata isolates from Europe and Africa using multilocus microsatellite analysis. Each isolate was first identified using phenotypic and molecular methods and subsequently, six unlinked microsatellite loci were analyzed using automated fluorescent genotyping. Genetic relationships were estimated using the minimum-spanning tree (MStree) method. Microsatellite analyses revealed the existence of 47 different genotypes. The fungal population showed an irregular distribution owing to the over-representation of genetically different infectious haplotypes. The most common genotype was MG-9, which was frequently found in both European and African isolates. In conclusion, the data reported here emphasize the role of specific C. glabrata genotypes in human infections for at least some decades and highlight the widespread distribution of some isolates, which seem to be more able to cause disease than others.


Subject(s)
Candida glabrata/classification , Candida glabrata/genetics , DNA, Fungal , Microsatellite Repeats , Multilocus Sequence Typing , Africa , Alleles , Candida glabrata/isolation & purification , Candidiasis/microbiology , Environmental Microbiology , Europe , Genetic Loci , Genetic Variation , Genotype , Haplotypes , Humans
7.
Mycoses ; 59(12): 781-786, 2016 Dec.
Article in English | MEDLINE | ID: mdl-27402377

ABSTRACT

Candidemia rate and species distribution vary according to the type of patients, country of origin and antifungal prophylaxis use. To present current candidemia epidemiological trends. A retrospective examination of candidemia in adults (≥18 years-old) hospitalised from 2007 to 2015. Cases were identified through the microbiology laboratory. Candida species were distinguished based on colony morphology and VITEK-2 YBC cards, (bioMerieux, Durham, NC, USA). Patient characteristics, species distribution, source and outcome were assessed. We encountered 275 patients (294 episodes) with candidemia. The rate of candidemia dropped in 2010 (P = 0.003) without further decline. Nearly all cases (97.5%) were healthcare-associated. C. albicans (n = 118) and C. glabrata (n = 77) proportions varied without a discernable trend. C. glabrata was more common in diabetics [52.9% vs. 32.0% (non-diabetics); P = 0.004] and abdominal sources [53.3% vs. 35.5% (other sources); P = 0.03], especially gastric/duodenal foci [88.9% vs. 44.1% (other abdominal foci); P = 0.02]. All-cause 30-day mortality rate was 43.3% without changes over time or differences between C. albicans and C. glabrata. In conclusion, the candidemia rate remains stable after a decline in 2010. C. albicans remains the most common species but C. glabrata predominates in diabetics and abdominal sources. These findings suggest possible species-related differences in colonisation dynamics or pathogenicity.


Subject(s)
Abdomen/microbiology , Candida albicans/isolation & purification , Candida glabrata/isolation & purification , Candidemia/microbiology , Diabetes Complications/microbiology , Adult , Aged , Aged, 80 and over , Candida albicans/classification , Candida albicans/genetics , Candida glabrata/classification , Candida glabrata/genetics , Candidemia/blood , Candidemia/mortality , Diabetes Complications/blood , Diabetes Complications/mortality , Female , Humans , Male , Middle Aged , Retrospective Studies
8.
Mycoses ; 59(2): 117-26, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26667499

ABSTRACT

Oral candidiasis is the most frequent fungal infection of the oral cavity. Clinical diagnoses require mycological confirmation, which is time-consuming in case of culture testing. The aim of the study was to identify signature volatiles to develop a chairside breath test to diagnose oral candidiasis. Headspaces above Candida albicans, glabrata, tropicalis, krusei cultures, and growth media as control were analysed after eight and 24 h using offline gas chromatography and mass spectrometry. The identification of signature volatiles was assisted using various microbial databases. Retrieved volatile patterns enabled Candida species discrimination in vitro. For C. albicans 3-methyl-2-butanone and styrene and for C. krusei a combination of p-xylene, 2-octanone, 2-heptanone and n-butyl acetate were found to be specific. 1-hexanol was found in C. tropicalis, but is emitted by a variety of other microorganisms. C. glabrata was characterised through the absence of these volatiles. The development of a breath test is a promising approach in confirming suspicions of oral candidiasis. To confirm the retrieved results in vivo, breath tests in affected and healthy subjects have to be performed.


Subject(s)
Candida/classification , Candida/isolation & purification , Candidiasis, Oral/diagnosis , Volatile Organic Compounds/analysis , Acetates/analysis , Adult , Breath Tests , Candida/chemistry , Candida albicans/classification , Candida albicans/isolation & purification , Candida glabrata/classification , Candida glabrata/isolation & purification , Candida tropicalis/classification , Candida tropicalis/isolation & purification , Candidiasis, Oral/microbiology , Chromatography, Gas/methods , Diagnosis, Differential , Hexanols/analysis , Humans , Ketones/analysis , Male , Mass Spectrometry/methods , Pentanones/analysis , Styrene/analysis , Xylenes/analysis
9.
Mycopathologia ; 181(11-12): 871-878, 2016 Dec.
Article in English | MEDLINE | ID: mdl-27681573

ABSTRACT

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.


Subject(s)
Antifungal Agents/pharmacology , Candida glabrata/drug effects , Candida glabrata/isolation & purification , Candidiasis/epidemiology , Candidiasis/microbiology , Argentina/epidemiology , Candida glabrata/classification , Culture Media , Humans , Microbiological Techniques , Molecular Diagnostic Techniques , Polymerase Chain Reaction , Prevalence , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
10.
Med Mycol ; 53(5): 462-9, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25841053

ABSTRACT

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.


Subject(s)
Antifungal Agents/pharmacology , Candida glabrata/isolation & purification , Candidiasis/epidemiology , Drug Resistance, Fungal , Fluconazole/pharmacology , Mycological Typing Techniques , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Candida glabrata/chemistry , Candida glabrata/classification , Candida glabrata/drug effects , Candidiasis/microbiology , Cluster Analysis , France/epidemiology , Genotype , Humans , Microbial Sensitivity Tests , Microsatellite Repeats , Molecular Typing , Phenotype , Topography, Medical , Tunisia/epidemiology
11.
Yeast ; 31(8): 279-88, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24861573

ABSTRACT

The yeast Candida glabrata has become a major fungal opportunistic pathogen of humans since the 1980s. Contrary to what its name suggests, it is much closer, phylogenetically, to the model yeast Saccharomyces cerevisiae than to the most prevalent human fungal pathogen, Candida albicans. Its similarity to S. cerevisiae fortunately extends to their amenability to molecular genetics methods. C. glabrata is now described as part of the Nakaseomyces clade, which includes two new pathogens and other environmental species. C. glabrata is likely a commensal species of the human digestive tract, but systemic infections of immunocompromised patients are often fatal. In addition to being the subject of active medical research, other studies on C. glabrata focus on fundamental aspects of evolution of yeast genomes and adaptation. For example, the genome of C. glabrata has undergone major gene and intron loss compared to S. cerevisiae. It is also an apparently asexual species, a feature that inevitably leads to questions about the species' evolutionary past, present and future. On-going research with this yeast continues to address various aspects of adaptation to the human host and mechanisms of evolution in the Saccharomycetaceae, major model organisms for biology.


Subject(s)
Candida glabrata/classification , Candida glabrata/genetics , Candidiasis/microbiology , Adaptation, Biological , Candida glabrata/isolation & purification , Candida glabrata/physiology , Humans , Immunocompromised Host , Phylogeny , Virulence
12.
BMC Genomics ; 14: 623, 2013 Sep 14.
Article in English | MEDLINE | ID: mdl-24034898

ABSTRACT

BACKGROUND: Candida glabrata follows C. albicans as the second or third most prevalent cause of candidemia worldwide. These two pathogenic yeasts are distantly related, C. glabrata being part of the Nakaseomyces, a group more closely related to Saccharomyces cerevisiae. Although C. glabrata was thought to be the only pathogenic Nakaseomyces, two new pathogens have recently been described within this group: C. nivariensis and C. bracarensis. To gain insight into the genomic changes underlying the emergence of virulence, we sequenced the genomes of these two, and three other non-pathogenic Nakaseomyces, and compared them to other sequenced yeasts. RESULTS: Our results indicate that the two new pathogens are more closely related to the non-pathogenic N. delphensis than to C. glabrata. We uncover duplications and accelerated evolution that specifically affected genes in the lineage preceding the group containing N. delphensis and the three pathogens, which may provide clues to the higher propensity of this group to infect humans. Finally, the number of Epa-like adhesins is specifically enriched in the pathogens, particularly in C. glabrata. CONCLUSIONS: Remarkably, some features thought to be the result of adaptation of C. glabrata to a pathogenic lifestyle, are present throughout the Nakaseomyces, indicating these are rather ancient adaptations to other environments. Phylogeny suggests that human pathogenesis evolved several times, independently within the clade. The expansion of the EPA gene family in pathogens establishes an evolutionary link between adhesion and virulence phenotypes. Our analyses thus shed light onto the relationships between virulence and the recent genomic changes that occurred within the Nakaseomyces. SEQUENCE ACCESSION NUMBERS: Nakaseomyces delphensis: CAPT01000001 to CAPT01000179Candida bracarensis: CAPU01000001 to CAPU01000251Candida nivariensis: CAPV01000001 to CAPV01000123Candida castellii: CAPW01000001 to CAPW01000101Nakaseomyces bacillisporus: CAPX01000001 to CAPX01000186.


Subject(s)
Candida glabrata/classification , Genome, Fungal , Phylogeny , Saccharomycetales/classification , Candida glabrata/genetics , DNA, Fungal/genetics , Evolution, Molecular , Saccharomycetales/genetics , Selection, Genetic , Sequence Analysis, DNA
13.
Antimicrob Agents Chemother ; 57(1): 177-82, 2013 01.
Article in English | MEDLINE | ID: mdl-23089746

ABSTRACT

FKS mutant isolates associated with breakthrough or failure cases are emerging in clinical settings. Discrimination of these from wild-type (wt) isolates in a routine laboratory setting is complicated. We evaluated the ability of caspofungin MIC determination using the new Vitek 2 AST-Y06 yeast susceptibility card to correctly identify the fks mutants from wt isolates and compared the performance to those of the CLSI and EUCAST reference methods. A collection of 98 Candida isolates, including 31 fks hot spot mutants, were included. Performance was evaluated using the FKS genotype as the "gold standard" and compared to those of the CLSI and EUCAST methodologies. The categorical agreement for Vitek 2 was 93.9%, compared to 88.4% for the CLSI method and 98.7% for the EUCAST method. Vitek 2 misclassified 19.4% (6/31) of the fks mutant isolates as susceptible, in contrast to <4% for each of the reference methods. The overall essential agreement between the CLSI method and Vitek 2 MICs was 92.6% (88/95) but was substantially lower for fks mutant isolates (78.6% [22/28]). Correct discrimination between susceptible and intermediate Candida glabrata isolates was not possible, as the revised species-specific susceptibility breakpoint was not included in the Vitek 2 detection range (MIC of ≤0.250 to ≥4 mg/liter). In conclusion, the Vitek 2 allowed correct categorization of all wt isolates as susceptible. However, despite an acceptable categorical agreement, it failed to reliably classify isolates harboring fks hot spot mutations as intermediate or resistant, which was in part due to the fact that the detection range did not span the susceptibility breakpoint for C. glabrata.


Subject(s)
Antifungal Agents/pharmacology , Candida glabrata/genetics , Candida/genetics , Candidiasis/drug therapy , Echinocandins/pharmacology , Fungal Proteins/genetics , Glucosyltransferases/genetics , Candida/classification , Candida/drug effects , Candida/isolation & purification , Candida glabrata/classification , Candida glabrata/drug effects , Candida glabrata/isolation & purification , Candidiasis/microbiology , Caspofungin , Drug Resistance, Fungal/drug effects , Drug Resistance, Fungal/genetics , Humans , Lipopeptides , Microbial Sensitivity Tests , Mutation , Reagent Strips/standards , Sensitivity and Specificity
14.
Eur J Clin Microbiol Infect Dis ; 31(1): 83-91, 2012 Jan.
Article in English | MEDLINE | ID: mdl-21598073

ABSTRACT

We investigated six microsatellite markers to type 85 unrelated and 118 related isolates of Candida glabrata from 36 patients. Three new markers were selected from the complete sequence of CBS138 and three previously described markers, RPM2, MTI and ERG3 were used. We found a genetic diversity of 0.949 by combining four of them. By applying the new microsatellite markers GLM4, GLM5 and GLM6 we were able to discriminate 29 isolates, originally identified by the more established markers, RPM2, MTI and ERG3. When epidemiologically closely related isolates from 36 patients were typed, 25 patients (72%) exhibited identical or highly related multilocus genotypes. We noted a microvariation in 4 of the patients. This minor change of one locus could be explained by a single step mutation. Since one of these patients had not received antifungal treatment; thus, the relationship between genome variation and antifungal therapy remains controversial. We can conclude from our analysis of these new microsatellite markers that they are highly selective and therefore should be considered as a useful typing system for differentiating related and unrelated isolates of C. glabrata, as well as being able to detect microvariation.


Subject(s)
Candida glabrata/classification , Candida glabrata/genetics , Candidiasis/microbiology , Microsatellite Repeats , Antifungal Agents/pharmacology , Base Sequence , Candida glabrata/drug effects , Candida glabrata/isolation & purification , Candidiasis/drug therapy , DNA, Fungal/genetics , Female , Fluconazole/pharmacology , Genetic Markers , Genetic Variation , Genotype , Humans , Male , Mutation , Mycological Typing Techniques , Sequence Analysis, DNA
16.
Med Mycol ; 49(1): 10-5, 2011 Jan.
Article in English | MEDLINE | ID: mdl-20586679

ABSTRACT

We have noted that, during the last few years, there has been a redistribution of the most common Candida species with an increase in non-C. albicans Candida species, particularly Candida glabrata. In many countries, the high frequency of Candida glabrata shows the highest resistance rates. The main objective of this investigation was to analyze the genotypic variability of invasive C. glabrata isolates recovered over a period of six years and assess their in vitro susceptibility to fluconazole to determine the possible existence of relationships between genotype and susceptibility. We collected 50 invasive C. glabrata isolates (21.4%) from January 2001 to December 2007. The in vitro susceptibility profiles as determined by the E-test method showed that 8.3% of the isolates were resistant to fluconazole. The typing with three microsatellite markers RPM2, MTI and ERG3 demonstrated 12 multilocus genotypes distributed irregularly with a predominance of G1 (38%). A cluster (G9) was found among isolates collected in the same ward, at the same time period, suggesting cross transmission. Eleven of 13 patients who had previously been colonized by C. glabrata, were infected by their colonizing strains. However, we noted after prolonged treatment with fluconazole that there was an increase of the MIC for an isolate from one patient and in another patient, the selection of a more resistant variant. In our study, we didn't find an association between genotype and susceptibility to fluconazole. In conclusion, the predominance of some genotypes could be explained by nosocomial transmission or a selective ecological advantage rather than an emergence of a resistant isolate.


Subject(s)
Candida glabrata/classification , Candida glabrata/drug effects , Candidiasis/microbiology , Microsatellite Repeats , Molecular Typing , Mycological Typing Techniques , Adult , Antifungal Agents/pharmacology , Candida glabrata/genetics , Candida glabrata/isolation & purification , Candidiasis/transmission , Cluster Analysis , DNA, Fungal/genetics , Female , Fluconazole/pharmacology , Genetic Variation , Hospitals , Humans , Male , Microbial Sensitivity Tests , Molecular Epidemiology , Tunisia
17.
Eukaryot Cell ; 9(4): 619-25, 2010 Apr.
Article in English | MEDLINE | ID: mdl-20190071

ABSTRACT

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


Subject(s)
Candida glabrata/genetics , Candida glabrata/metabolism , Candidiasis , Population Surveillance , Recombination, Genetic , Sequence Analysis, DNA , Bacterial Typing Techniques , Baltimore/epidemiology , Candida glabrata/classification , Candidiasis/blood , Candidiasis/epidemiology , Candidiasis/genetics , Cross Infection/blood , Cross Infection/genetics , Cross Infection/microbiology , Genetics, Population , Genotype , Georgia/epidemiology , Humans , Phylogeny , San Francisco/epidemiology
18.
J Low Genit Tract Dis ; 15(4): 263-7, 2011 Oct.
Article in English | MEDLINE | ID: mdl-21959570

ABSTRACT

OBJECTIVE: : This study aimed to explore the role of hormone replacement therapy (HRT) in susceptibility to vulvovaginal candidiasis (VVC) in a private vulval disease referral practice. METHODS: : Between January 2009 and December 2010, 149 healthy, nondiabetic patients with vulvar conditions were compared for significant differences in vaginal swab result, age, and diagnosis between those using and not using HRT. Detailed clinical data were collected from those with VVC. RESULTS: : The mean ages of the HRT (n = 70) and non-HRT (n = 79) groups were 62.5 and 62.5 years, respectively. Positive cultures for Candida were found in 34 (48.5%) of 70 patients on HRT and in 2 (3%) of 79 subjects not on HRT (p < .001). Culture-positive, clinical VVC was identified in 34 (49%) of 70 patients on HRT and in 1 (1%) of 79 patients not on HRT (p < .001). Candida species (32 Candida albicans and 2 Candida glabrata) were isolated from the 34 VVC patients, and of these, 23 (67%) had a history of recurrent or chronic candidiasis before menopause. All 34 had been previously treated with antifungal therapy without ceasing HRT and had been unresponsive to treatment or had relapse after treatment. In 27 (79%) of 34 patients, HRT was suspended during treatment. Of those who remained on HRT during treatment or resumed it after treatment, prophylactic antifungal treatment was initiated in 15 (44%) to prevent recurrence. All patients responded to the antifungal treatment provided HRT was suspended or prophylactic treatment was used. CONCLUSIONS: : Postmenopausal women taking HRT are significantly more prone to develop VVC than women who are not and those with VVC are likely to have been susceptible to it before menopause.


Subject(s)
Candidiasis, Vulvovaginal/chemically induced , Candidiasis, Vulvovaginal/epidemiology , Hormone Replacement Therapy/adverse effects , Postmenopause , Aged , Aged, 80 and over , Candida albicans/classification , Candida albicans/isolation & purification , Candida glabrata/classification , Candida glabrata/isolation & purification , Female , Humans , Middle Aged
19.
Poult Sci ; 100(4): 101003, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33676095

ABSTRACT

Previously, a fungus was isolated from a diseased pigeon group clinically suspected of being infected with Candida. The fungus was subsequently identified as Candida glabrata using morphology, physiology, biochemistry, and molecular biology testing methods. In the present study, to determine the controlling effects of Chinese herbal medicine for C. glabrata, the bacteriostatic effects of the ethanol extracts Acorus gramineus, Sophora flavescens, Polygonum hydropiper, Cassia obtusifolia, Pulsatilla chinensis, Dandelion, and Cortex phellodendri on C. glabrata in vitro were analyzed. The results showed that the minimum inhibitory concentrations (MIC80) of Cortex phellodendri was 0.25 µg/µL. Meanwhile, that of S. flavescens was 32 µg/µL; C. obtusifolia was 56 µg/µL; A. gramineus and Polygonum hydropiper was 64 µg/µL; and P. chinensis was 112 µg/µL. However, MIC80 for Dandelion was undetectable. In addition, improved drug sensitivity tests revealed that colonies had grown after 24 h in the blank group, as well as the Polygonum hydropiper, P. chinensis, Dandelion, and ethanol groups. The colonies first appeared at the 48-hour point in the other drug-sensitive medium of Chinese herbal medicine. However, no colony growth was found in Cortex phellodendri medium, and the formation of the maximum colony diameter in that group was later than the blank group (e.g., 96 h in the blank group and 120 h in the Chinese herbal medicine group). It was observed that only 17 colony-forming units had grown in 125 µg/µL of the S. flavescens medium, which was significantly different from other groups. Also, the final colony diameter was significantly smaller than that of the other experimental groups. Therefore, it was determined that the A. gramineus, S. flavescens, Polygonum hydropiper, Cassia obtusifolia, P. chinensis, and Cortex phellodendri had certain inhibitory effects on the growth of the C. glabrata. Among those, it was observed that the Cortex phellodendri had the strongest inhibitory effects, followed by the S. flavescens. In the future, these Chinese herbal medicines are expected to be used to treat the fungal infections related to C. glabrata in poultry to improve production performance.


Subject(s)
Candida glabrata , Drugs, Chinese Herbal , Animals , Anti-Bacterial Agents/pharmacology , Bird Diseases/drug therapy , Bird Diseases/microbiology , Candida glabrata/classification , Candida glabrata/drug effects , Candida glabrata/isolation & purification , Columbidae/microbiology , Drugs, Chinese Herbal/pharmacology , Microbial Sensitivity Tests/veterinary
20.
J Clin Microbiol ; 48(11): 4028-34, 2010 Nov.
Article in English | MEDLINE | ID: mdl-20844221

ABSTRACT

Candida glabrata has emerged as the second most common etiologic agent, after Candida albicans, of superficial and invasive candidiasis in adults. Strain typing is essential for epidemiological investigation, but easy-to-use and reliable typing methods are still lacking. We report the use of a multilocus microsatellite typing method with a set of eight markers on a panel of 180 strains, including 136 blood isolates from hospitalized patients and 34 digestive tract isolates from nonhospitalized patients. A total of 44 different alleles were observed, generating 87 distinct genotypes. In addition to perfect reproducibility, typing ability, and stability, the method had a discriminatory power calculated at 0.97 when all 8 markers were associated, making it suitable for tracing strains. In addition, it is shown that digestive tract isolates differed from blood culture isolates by exhibiting a higher genotypic diversity associated with different allelic frequencies and preferentially did not group in clonal complexes (CCs). The demonstration of the occurrence of microevolution in digestive strains supports the idea that C. glabrata can be a persistent commensal of the human gut.


Subject(s)
Candida glabrata/classification , Candida glabrata/genetics , Candidiasis/microbiology , Digestive System/microbiology , Fungemia/microbiology , Microsatellite Repeats , Mycological Typing Techniques/methods , Adult , DNA, Fungal/genetics , Genetic Variation , Genotype , Humans , Molecular Epidemiology/methods , Reproducibility of Results , Sensitivity and Specificity
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