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Sample records for gordonii modulates candida

  1. Interaction of Candida albicans cell wall Als3 protein with Streptococcus gordonii SspB adhesin promotes development of mixed-species communities.

    PubMed

    Silverman, Richard J; Nobbs, Angela H; Vickerman, M Margaret; Barbour, Michele E; Jenkinson, Howard F

    2010-11-01

    Candida albicans colonizes human mucosa and prosthetic surfaces associated with artificial joints, catheters, and dentures. In the oral cavity, C. albicans coexists with numerous bacterial species, and evidence suggests that bacteria may modulate fungal growth and biofilm formation. Streptococcus gordonii is found on most oral cavity surfaces and interacts with C. albicans to promote hyphal and biofilm formation. In this study, we investigated the role of the hyphal-wall protein Als3p in interactions of C. albicans with S. gordonii. Utilizing an ALS3 deletion mutant strain, it was shown that cells were not affected in initial adherence to the salivary pellicle or in hyphal formation in the planktonic phase. However, the Als3(-) mutant was unable to form biofilms on the salivary pellicle or deposited S. gordonii DL1 wild-type cells, and after initial adherence, als3Δ/als3Δ (ΔALS3) cells became detached concomitant with hyphal formation. In coaggregation assays, S. gordonii cells attached to, and accumulated around, hyphae formed by C. albicans wild-type cells. However, streptococci failed to attach to hyphae produced by the ΔALS3 mutant. Saccharomyces cerevisiae S150-2B cells expressing Als3p, but not control cells, supported binding of S. gordonii DL1. However, S. gordonii Δ(sspA sspB) cells deficient in production of the surface protein adhesins SspA and SspB showed >50% reduced levels of binding to S. cerevisiae expressing Als3p. Lactococcus lactis cells expressing SspB bound avidly to S. cerevisiae expressing Als3p, but not to S150-2B wild-type cells. These results show that recognition of C. albicans by S. gordonii involves Als3 protein-SspB protein interaction, defining a novel mechanism in fungal-bacterial communication.

  2. Glucose modulates antimicrobial photodynamic inactivation of Candida albicans in biofilms.

    PubMed

    Suzuki, Luis Cláudio; Kato, Ilka Tiemy; Prates, Renato Araujo; Sabino, Caetano Padial; Yoshimura, Tania Mateus; Silva, Tamires Oliveira; Ribeiro, Martha Simões

    2017-03-01

    Candida albicans biofilm is a main cause of infections associated with medical devices such as catheters, contact lens and artificial joint prosthesis. The current treatment comprises antifungal chemotherapy that presents low success rates. Photodynamic inactivation (PDI) involves the combination of a photosensitizing compound (PS) and light to generate oxidative stress that has demonstrated effective antimicrobial activity against a broad-spectrum of pathogens, including C. albicans. This fungus senses glucose inducing an upregulation of membrane transporters that can facilitate PS uptake into the cell. The aim of this study was to evaluate the effects of glucose on methylene blue (MB) uptake and its influence on PDI efficiency when combined to a red LED with central wavelength at λ=660nm. C. albicans biofilms were grown on hydrogel disks. Prior to PDI assays, MB uptake tests were performed with and without glucose-sensitization. In this system, the optimum PS administration was determined as 500μM of MB in contact with the biofilm during 30min before irradiation. Irradiation was performed during 3, 6, 9, 12, 15 and 18min with irradiance of 127.3mW/cm(2). Our results showed that glucose was able to increase MB uptake in C. albicans cells. In addition, PDI without glucose showed a higher viability reduction until 6min; after 9min, glucose group demonstrated a significant decrease in cell viability when compared to glucose-free group. Taken together, our data suggest that glucose is capable to enhance MB uptake and modulate photodynamic inactivation of C. albicans biofilm.

  3. Do Candida spp. "read" Nietzsche? Can xenobiotics modulate their aggressiveness? Proposition that chemicals may interfere in their virulence attributes.

    PubMed

    Rosa, Edvaldo Antonio Ribeiro

    2012-01-01

    As well as the host, opportunist Candida spp. enface all sorts of exogenous chemicals, so-called xenobiotics. It is plausible that xenobiotics exert some effects on such microorganisms; among them, the modulation of virulence attributes.

  4. Involvement of an inducible fructose phosphotransferase operon in Streptococcus gordonii biofilm formation.

    PubMed

    Loo, C Y; Mitrakul, K; Voss, I B; Hughes, C V; Ganeshkumar, N

    2003-11-01

    fructose, confirming that fruR is a transcriptional repressor of the fructose PTS operon. These results suggest that the regulation of fructose transport and metabolism in S. gordonii is intricately tied to carbon catabolite control and the ability to form biofilms. Carbon catabolite control, which modulates carbon flux in response to environmental nutritional levels, appears to be important in the regulation of bacterial biofilms.

  5. Virulence modulation of Candida albicans biofilms by metal ions commonly released from orthodontic devices.

    PubMed

    Ronsani, Maiara Medeiros; Mores Rymovicz, Alinne Ulbrich; Meira, Thiago Martins; Trindade Grégio, Ana Maria; Guariza Filho, Odilon; Tanaka, Orlando Motohiro; Ribeiro Rosa, Edvaldo Antonio

    2011-12-01

    The installation of metal devices leads to an increase in the salivary concentration of metal ions and in the growth of salivary Candida spp. However, the relationship between released metal ions and Candida virulence has not been previously examined. The objective of this study was to evaluate whether metal ions affect fungal virulence. We prepared culture media containing Ni(2+), Fe(3+), Cr(3+), Co(2+) or a mixture of these metal ions at concentrations similar to those released in saliva of orthodontic patients. Biofilms of Candida albicans SC5314 were grown for 72 h and their biomasses were determined. The supernatants were analyzed for secretory aspartyl protease (SAP) and hemolysin activities. To verify changes in virulence following treatment with metals, proteolytic and hemolytic activities were converted into specific activities. The results revealed that all ions, except Co(2+), caused increases in biofilm biomass. In addition, Ni(2+) caused an increase in SAP activity and Fe(3+) reduced hemolytic activity. However, the SAP and hemolysin activities in the presence of the mixture of ions did not differ from those of control. These results indicate that metal ions released during the degradation of orthodontic appliances can modulate virulence factors in C. albicans biofilms.

  6. Arginine-Ornithine Antiporter ArcD Controls Arginine Metabolism and Interspecies Biofilm Development of Streptococcus gordonii*♦

    PubMed Central

    Sakanaka, Akito; Kuboniwa, Masae; Takeuchi, Hiroki; Hashino, Ei; Amano, Atsuo

    2015-01-01

    Arginine is utilized by the oral inhabitant Streptococcus gordonii as a substrate of the arginine deiminase system (ADS), eventually producing ATP and NH3, the latter of which is responsible for microbial resistance to pH stress. S. gordonii expresses a putative arginine-ornithine antiporter (ArcD) whose function has not been investigated despite relevance to the ADS and potential influence on inter-bacterial communication with periodontal pathogens that utilize amino acids as a main energy source. Here, we generated an S. gordonii ΔarcD mutant to explore the role of ArcD in physiological homeostasis and bacterial cross-feeding. First, we confirmed that S. gordonii ArcD plays crucial roles for mediating arginine uptake and promoting bacterial growth, particularly under arginine-limited conditions. Next, metabolomic profiling and transcriptional analysis of the ΔarcD mutant revealed that deletion of this gene caused intracellular accumulation of ornithine leading to malfunction of the ADS and suppression of de novo arginine biosynthesis. The mutant strain also showed increased susceptibility to low pH stress due to reduced production of ammonia. Finally, accumulation of Fusobacterium nucleatum was found to be significantly decreased in biofilm formed by the ΔarcD mutant as compared with the wild-type strain, although ornithine supplementation restored fusobacterium biovolume in dual-species biofilms with the ΔarcD mutant and also enhanced single species biofilm development by F. nucleatum. Our results are the first direct evidence showing that S. gordonii ArcD modulates not only alkali and energy production but also interspecies interaction with F. nucleatum, thus initiating a middle stage of periodontopathic biofilm formation, by metabolic cross-feeding. PMID:26085091

  7. Essential Functional Modules for Pathogenic and Defensive Mechanisms in Candida albicans Infections

    PubMed Central

    Tsai, I-Chun; Lin, Che; Chuang, Yung-Jen

    2014-01-01

    The clinical and biological significance of the study of fungal pathogen Candida albicans (C. albicans) has markedly increased. However, the explicit pathogenic and invasive mechanisms of such host-pathogen interactions have not yet been fully elucidated. Therefore, the essential functional modules involved in C. albicans-zebrafish interactions were investigated in this study. Adopting a systems biology approach, the early-stage and late-stage protein-protein interaction (PPI) networks for both C. albicans and zebrafish were constructed. By comparing PPI networks at the early and late stages of the infection process, several critical functional modules were identified in both pathogenic and defensive mechanisms. Functional modules in C. albicans, like those involved in hyphal morphogenesis, ion and small molecule transport, protein secretion, and shifts in carbon utilization, were seen to play important roles in pathogen invasion and damage caused to host cells. Moreover, the functional modules in zebrafish, such as those involved in immune response, apoptosis mechanisms, ion transport, protein secretion, and hemostasis-related processes, were found to be significant as defensive mechanisms during C. albicans infection. The essential functional modules thus determined could provide insights into the molecular mechanisms of host-pathogen interactions during the infection process and thereby devise potential therapeutic strategies to treat C. albicans infection. PMID:24757665

  8. Ribosomal protein S6 phosphorylation is controlled by TOR and modulated by PKA in Candida albicans.

    PubMed

    Chowdhury, Tahmeena; Köhler, Julia R

    2015-10-01

    TOR and PKA signaling pathways control eukaryotic cell growth and proliferation. TOR activity in model fungi, such as Saccharomyces cerevisiae, responds principally to nutrients, e.g., nitrogen and phosphate sources, which are incorporated into the growing cell mass; PKA signaling responds to the availability of the cells' major energy source, glucose. In the fungal commensal and pathogen, Candida albicans, little is known of how these pathways interact. Here, the signal from phosphorylated ribosomal protein S6 (P-S6) was defined as a surrogate marker for TOR-dependent anabolic activity in C. albicans. Nutritional, pharmacologic and genetic modulation of TOR activity elicited corresponding changes in P-S6 levels. The P-S6 signal corresponded to translational activity of a GFP reporter protein. Contributions of four PKA pathway components to anabolic activation were then examined. In high glucose concentrations, only Tpk2 was required to upregulate P-S6 to physiologic levels, whereas all four tested components were required to downregulate P-S6 in low glucose. TOR was epistatic to PKA components with respect to P-S6. In many host niches inhabited by C. albicans, glucose is scarce, with protein being available as a nitrogen source. We speculate that PKA may modulate TOR-dependent cell growth to a rate sustainable by available energy sources, when monomers of anabolic processes, such as amino acids, are abundant.

  9. Dietary Carbohydrates Modulate Candida albicans Biofilm Development on the Denture Surface

    PubMed Central

    Santana, Ivone Lima; Gonçalves, Letícia Machado; de Vasconcellos, Andréa Araújo; da Silva, Wander José; Cury, Jaime Aparecido; Cury, Altair Antoninha Del Bel

    2013-01-01

    The purpose of this study was to investigate whether dietary carbohydrates can modulate the development of Candida albicans biofilms on the denture material surface. Poly (methyl methacrylate) acrylic resin discs were fabricated and had their surface roughness measured. Biofilms of C. albicans ATCC 90028 were developed on saliva-coated specimens in culture medium without (control) or with carbohydrate supplementation by starch, starch+sucrose, glucose, or sucrose for 72 h. The cell count, metabolic activity, biovolume, average thickness, and roughness coefficient were evaluated at the adhesion phase (1.5 h) and after 24, 48, and 72 h. The secretion of proteinases and phospholipases, cell surface energy, and production of extra/intracellular polysaccharides were analyzed after 72 h of biofilm development. Data were analyzed by one- and two-way ANOVA followed by Tukey’s test at 5% significance level. In the early stages of colonization (adhesion and 24 h), the glucose group showed the highest cell counts and metabolic activity among the groups (p<0.05). After maturation (48 and 72 h), biofilms exposed to glucose, sucrose, or starch+sucrose showed higher cell counts and metabolic activity than the control and starch groups (p<0.001). Compared to the control group, biofilms developed on starch or starch+sucrose had more proteinase activity (p<0.001), whereas biofilms developed on glucose or sucrose had more phospholipase activity (p<0.05). Exposure to starch+sucrose increased the production of extracellular and intracellular polysaccharides (p<0.05). Biofilms developed on starch or without carbohydrate supplementation presented cells with more hydrophobic behavior compared to the other groups. Confocal images showed hyphae forms on biofilms exposed to starch or starch+sucrose. Within the conditions studied, it can be concluded that dietary carbohydrates can modulate biofilm development on the denture surface by affecting virulence factors and structural features

  10. Functions of Cell Surface-Anchored Antigen I/II Family and Hsa Polypeptides in Interactions of Streptococcus gordonii with Host Receptors

    PubMed Central

    Jakubovics, Nicholas S.; Kerrigan, Steven W.; Nobbs, Angela H.; Strömberg, Nicklas; van Dolleweerd, Craig J.; Cox, Dermot M.; Kelly, Charles G.; Jenkinson, Howard F.

    2005-01-01

    Streptococcus gordonii colonizes multiple sites within the human oral cavity. This colonization depends upon the initial interactions of streptococcal adhesins with host receptors. The adhesins that bind salivary agglutinin glycoprotein (gp340) and human cell surface receptors include the antigen I/II (AgI/II) family polypeptides SspA and SspB and a sialic acid-binding surface protein designated Hsa or GspB. In this study we determined the relative functions of the AgI/II polypeptides and Hsa in interactions of S. gordonii DL1 (Challis) with host receptors. For an isogenic mutant with the sspA and sspB genes deleted the levels of adhesion to surface-immobilized gp340 were reduced 40%, while deletion of the hsa gene alone resulted in >80% inhibition of bacterial cell adhesion to gp340. Adhesion of S. gordonii DL1 cells to gp340 was sialidase sensitive, verifying that Hsa has a major role in mediating sialic acid-specific adhesion to gp340. Conversely, aggregation of S. gordonii cells by fluid-phase gp340 was not affected by deletion of hsa but was eliminated by deletion of the sspA and sspB genes. Deletion of the AgI/II polypeptide genes had no measurable effect on hsa mRNA levels or Hsa surface protein expression, and deletion of hsa did not affect AgI/II polypeptide expression. Further analysis of mutant phenotypes showed that the Hsa and AgI/II proteins mediated adhesion of S. gordonii DL1 to human HEp-2 epithelial cells. Hsa was also a principal streptococcal cell surface component promoting adhesion of human platelets to immobilized streptococci, but Hsa and AgI/II polypeptides acted in concert in mediating streptococcal cell-platelet aggregation. The results suggest that Hsa directs primary adhesion events for S. gordonii DL1 (Challis) with immobilized gp340, epithelial cells, and platelets. AgI/II polypeptides direct gp340-mediated aggregation, facilitate multimodal interactions necessary for platelet aggregation, and modulate S. gordonii-host engagements

  11. Cell Intrinsic Galectin-3 Attenuates Neutrophil ROS-Dependent Killing of Candida by Modulating CR3 Downstream Syk Activation

    PubMed Central

    Wu, Sheng-Yang; Huang, Juin-Hua; Chen, Wen-Yu; Chan, Yi-Chen; Lin, Chun-Hung; Chen, Yee-Chun; Liu, Fu-Tong; Wu-Hsieh, Betty A.

    2017-01-01

    Invasive candidiasis is a leading cause of nosocomial bloodstream infection. Neutrophils are the important effector cells in host resistance to candidiasis. To investigate the modulation of neutrophil fungicidal function will advance our knowledge on the control of candidiasis. While recombinant galectin-3 enhances neutrophil phagocytosis of Candida, we found that intracellular galectin-3 downregulates neutrophil fungicidal functions. Co-immunoprecipitation and immunofluorescence staining reveal that cytosolic gal3 physically interacts with Syk in neutrophils after Candida stimulation. Gal3−/− neutrophils have higher level of Syk activation as well as greater abilities to generate reactive oxygen species (ROS) and kill Candida than gal3+/+ cells. While galectin-3 deficiency modulates neutrophil and macrophage activation and the recruitment of monocytes and dendritic cells, the deficiency does not affect the numbers of infiltrating neutrophils or macrophages. Galectin-3 deficiency ameliorates systemic candidiasis by reducing fungal burden, renal pathology, and mortality. Adoptive transfer experiments demonstrate that cell intrinsic galectin-3 negatively regulates neutrophil effector functions against candidiasis. Reducing galectin-3 expression or activity by siRNA or gal3 inhibitor TD139 enhances human neutrophil ROS production. Mice treated with TD139 have enhanced ability to clear the fungus. Our work unravels the mechanism by which galectin-3 regulates Syk-dependent neutrophil fungicidal functions and raises the possibility that blocking gal3 in neutrophils may be a promising therapeutic strategy for treating systemic candidiasis. PMID:28217127

  12. Phytochemical Analysis and Modulation of Antibiotic Activity by Luehea paniculata Mart. & Zucc. (Malvaceae) in Multiresistant Clinical Isolates of Candida Spp.

    PubMed Central

    Calixto Júnior, João T.; Morais, Selene M.; Martins, Clécio G.; Vieira, Larissa G.; Morais-Braga, Maria Flaviana B.; Carneiro, Joara N. P.; Machado, Antonio J. P.; Menezes, Irwin R. A.; Tintino, Saulo R.; Coutinho, Henrique D. M.

    2015-01-01

    The high incidence of fungal infections has led to the continuous search for new drugs. Extracts of Luehea paniculata, a tree of multiple medicinal uses, were evaluated for anti-Candida activity, as well as its modulator potential of the Fluconazole antibiotic. Chemical prospecting of ethanol extracts of leaf and bark was carried out, the quantification of total phenols and flavonoids, characterized by the HPLC-DAD technique. The rosmarinic acid and the vitexin flavonoid were observed as major constituents in ELELP and ESWELP, respectively. Antioxidant activity was also evaluated by the method of scavenging the free radical DPPH, and quercetin was used as standard, obtaining IC50 values: 0.341 (mg/mL) for ELELP and 0.235 (mg/mL) for ESWELP. The microdilution assay was performed for antifungal activity against strains of Candida albicans, C. krusei, and C. tropicalis and showed minimum inhibitory concentrations values ≥1024 μg/mL. In the modulator action of extracts on Fluconazole against multiresistant clinical isolates of Candida (subinhibitory concentration minimum of 128 μg/mL), a significant synergism was observed, indicating that the extracts potentiated the antifungal effect against C. tropicalis, where antioxidant flavonoids could be responsible. This is the first report about modifying activity of the antibiotic action of a species of the genus Luehea. PMID:25821822

  13. Lactobacillus paracasei modulates the immune system of Galleria mellonella and protects against Candida albicans infection.

    PubMed

    Rossoni, Rodnei Dennis; Fuchs, Beth Burgwyn; de Barros, Patrícia Pimentel; Velloso, Marisol Dos Santos; Jorge, Antonio Olavo Cardoso; Junqueira, Juliana Campos; Mylonakis, Eleftherios

    2017-01-01

    Probiotics have been described as a potential strategy to control opportunistic infections due to their ability to stimulate the immune system. Using the non-vertebrate model host Galleria mellonella, we evaluated whether clinical isolates of Lactobacillus spp. are able to provide protection against Candida albicans infection. Among different strains of Lactobacillus paracasei, Lactobacillus rhamnosus and Lactobacillus fermentum, we verified that L. paracasei 28.4 strain had the greatest ability to prolong the survival of larvae infected with a lethal dose of C. albicans. We found that the injection of 107 cells/larvae of L. paracasei into G. mellonella larvae infected by C. albicans increased the survival of these insects compared to the control group (P = 0.0001). After that, we investigated the immune mechanisms involved in the protection against C. albicans infection, evaluating the number of hemocytes and the gene expression of antifungal peptides. We found that L. paracasei increased the hemocyte quantity (2.38 x 106 cells/mL) in relation to the control group (1.29 x 106 cells/mL), indicating that this strain is capable of raising the number of circulating hemocytes into the G. mellonella hemolymph. Further, we found that L. paracasei 28.4 upregulated genes that encode the antifungal peptides galiomicin and gallerymicin. In relation to the control group, L. paracasei 28.4 increased gene expression of galiomicin by 6.67-fold and 17.29-fold for gallerymicin. Finally, we verified that the prophylactic provision of probiotic led to a significant reduction of the number of fungal cells in G. mellonella hemolymph. In conclusion, L. paracasei 28.4 can modulate the immune system of G. mellonella and protect against candidiasis.

  14. Regulation of the Cdc42/Cdc24 GTPase Module during Candida albicans Hyphal Growth

    PubMed Central

    Bassilana, Martine; Hopkins, Julie; Arkowitz, Robert A.

    2005-01-01

    The Rho G protein Cdc42 and its exchange factor Cdc24 are required for hyphal growth of the human fungal pathogen Candida albicans. Previously, we reported that strains ectopically expressing Cdc24 or Cdc42 are unable to form hyphae in response to serum. Here we investigated the role of these two proteins in hyphal growth, using quantitative real-time PCR to measure induction of hypha-specific genes together with time lapse microscopy. Expression of the hypha-specific genes examined depends on the cyclic AMP-dependent protein kinase A pathway culminating in the Efg1 and Tec1 transcription factors. We show that strains with reduced levels of CDC24 or CDC42 transcripts induce hypha-specific genes yet cannot maintain their expression in response to serum. Furthermore, in serum these mutants form elongated buds compared to the wild type and mutant budding cells, as observed by time lapse microscopy. Using Cdc24 fused to green fluorescent protein, we also show that Cdc24 is recruited to and persists at the germ tube tip during hyphal growth. Altogether these data demonstrate that the Cdc24/Cdc42 GTPase module is required for maintenance of hyphal growth. In addition, overexpression studies indicate that specific levels of Cdc24 and Cdc42 are important for invasive hyphal growth. In response to serum, CDC24 transcript levels increase transiently in a Tec1-dependent fashion, as do the G-protein RHO3 and the Rho1 GTPase activating protein BEM2 transcript levels. These results suggest that a positive feedback loop between Cdc24 and Tec1 contributes to an increase in active Cdc42 at the tip of the germ tube which is important for hypha formation. PMID:15755921

  15. Lactobacillus paracasei modulates the immune system of Galleria mellonella and protects against Candida albicans infection

    PubMed Central

    Rossoni, Rodnei Dennis; Fuchs, Beth Burgwyn; de Barros, Patrícia Pimentel; Velloso, Marisol dos Santos; Jorge, Antonio Olavo Cardoso; Junqueira, Juliana Campos; Mylonakis, Eleftherios

    2017-01-01

    Probiotics have been described as a potential strategy to control opportunistic infections due to their ability to stimulate the immune system. Using the non-vertebrate model host Galleria mellonella, we evaluated whether clinical isolates of Lactobacillus spp. are able to provide protection against Candida albicans infection. Among different strains of Lactobacillus paracasei, Lactobacillus rhamnosus and Lactobacillus fermentum, we verified that L. paracasei 28.4 strain had the greatest ability to prolong the survival of larvae infected with a lethal dose of C. albicans. We found that the injection of 107 cells/larvae of L. paracasei into G. mellonella larvae infected by C. albicans increased the survival of these insects compared to the control group (P = 0.0001). After that, we investigated the immune mechanisms involved in the protection against C. albicans infection, evaluating the number of hemocytes and the gene expression of antifungal peptides. We found that L. paracasei increased the hemocyte quantity (2.38 x 106 cells/mL) in relation to the control group (1.29 x 106 cells/mL), indicating that this strain is capable of raising the number of circulating hemocytes into the G. mellonella hemolymph. Further, we found that L. paracasei 28.4 upregulated genes that encode the antifungal peptides galiomicin and gallerymicin. In relation to the control group, L. paracasei 28.4 increased gene expression of galiomicin by 6.67-fold and 17.29-fold for gallerymicin. Finally, we verified that the prophylactic provision of probiotic led to a significant reduction of the number of fungal cells in G. mellonella hemolymph. In conclusion, L. paracasei 28.4 can modulate the immune system of G. mellonella and protect against candidiasis. PMID:28267809

  16. Robust Extracellular pH Modulation by Candida albicans during Growth in Carboxylic Acids

    PubMed Central

    Danhof, Heather A.; Vylkova, Slavena; Vesely, Elisa M.; Ford, Amy E.; Gonzalez-Garay, Manuel

    2016-01-01

    ABSTRACT The opportunistic fungal pathogen Candida albicans thrives within diverse niches in the mammalian host. Among the adaptations that underlie this fitness is an ability to utilize a wide array of nutrients, especially sources of carbon that are disfavored by many other fungi; this contributes to its ability to survive interactions with the phagocytes that serve as key barriers against disseminated infections. We have reported that C. albicans generates ammonia as a byproduct of amino acid catabolism to neutralize the acidic phagolysosome and promote hyphal morphogenesis in a manner dependent on the Stp2 transcription factor. Here, we report that this species rapidly neutralizes acidic environments when utilizing carboxylic acids like pyruvate, α-ketoglutarate (αKG), or lactate as the primary carbon source. Unlike in cells growing in amino acid-rich medium, this does not result in ammonia release, does not induce hyphal differentiation, and is genetically distinct. While transcript profiling revealed significant similarities in gene expression in cells grown on either carboxylic or amino acids, genetic screens for mutants that fail to neutralize αKG medium identified a nonoverlapping set of genes, including CWT1, encoding a transcription factor responsive to cell wall and nitrosative stresses. Strains lacking CWT1 exhibit retarded αKG-mediated neutralization in vitro, exist in a more acidic phagolysosome, and are more susceptible to macrophage killing, while double cwt1Δ stp2Δ mutants are more impaired than either single mutant. Together, our observations indicate that C. albicans has evolved multiple ways to modulate the pH of host-relevant environments to promote its fitness as a pathogen. PMID:27935835

  17. New oxypregnane glycosides from appetite suppressant herbal supplement Hoodia gordonii.

    PubMed

    Pawar, Rahul S; Shukla, Yatin J; Khan, Shabana I; Avula, Bharathi; Khan, Ikhlas A

    2007-06-01

    Hoodigosides A-K (1-11), eleven new oxypregnane glycosides and a previously reported oxypregnane glycoside P57AS3 were isolated from the aerial parts of Hoodia gordonii. The structures of these 12-O-beta-tigloyl isoramanone glycosides were determined on the basis of chemical evidence and extensive spectroscopic methods that include one-dimensional and two-dimensional NMR. Cytotoxicity and antioxidant activities of these compounds were tested in cell based assays where they were found to be inactive.

  18. Lactobacillus crispatus Modulates Vaginal Epithelial Cell Innate Response to Candida albicans

    PubMed Central

    Niu, Xiao-Xi; Li, Ting; Zhang, Xu; Wang, Su-Xia; Liu, Zhao-Hui

    2017-01-01

    Background: Vulvovaginal candidiasis is caused by Candida albicans. The vaginal epithelium, as the first site of the initial stage of infection by pathogens, plays an important role in resisting genital tract infections. Moreover, lactobacilli are predominant members of the vaginal microbiota that help to maintain a normal vaginal microenvironment. Therefore, Lactobacillus crispatus was explored for its capacity to intervene in the immune response of vaginal epithelial cells VK2/E6E7 to C. albicans. Methods: We examined the interleukin-2 (IL-2), 4, 6, 8, and 17 produced by VK2/E6E7 cells infected with C. albicans and treated with L. crispatus in vitro. The capacity of L. crispatus to adhere to VK2/E6E7 and inhibit C. albicans growth was also tested by scanning electron microscopy (SEM) and adhesion experiments. Results: Compared with group VK2/E6E7 with C. albicans, when treated with L. crispatus, the adhesion of C. albicans to VK2/E6E7 cells decreased significantly by 52.87 ± 1.22%, 47.03 ± 1.35%, and 42.20 ± 1.55% under competition, exclusion, and displacement conditions, respectively. SEM revealed that the invasion of C. albicans into VK2/E6E7 cells was caused by induced endocytosis and active penetration. L. crispatus could effectively protect the cells from the virulence of hyphae and spores of C. albicans and enhance the local immune function of the VK2/E6E7 cells. The concentrations of IL-2, 6, and 17 were upregulated significantly (P < 0.01) and that of IL-8 were downregulated significantly (P < 0.01) in infected VK2/E6E7 cells treated with L. crispatus. The concentration of IL-4 was similar to that of the group VK2/E6E7 with C. albicans (24.10 ± 0.97 vs. 23.12 ± 0.76 pg/ml, P = 0.221). Conclusions: L. crispatus can attenuate the virulence of C. albicans, modulate the secretion of cytokines and chemokines, and enhance the immune response of VK2/E6E7 cells in vitro. The vaginal mucosa has a potential function in the local immune responses against

  19. Shear stress modulates the thickness and architecture of Candida albicans biofilms in a phase-dependent manner

    PubMed Central

    Mukherjee, Pranab K.; Chand, David V.; Chandra, Jyotsna; Anderson, James M.; Ghannoum, Mahmoud A.

    2010-01-01

    Summary Biofilm formation plays an integral role in catheter-associated bloodstream infections caused by Candida albicans. Biofilms formed on catheters placed intravenously are exposed to shear stress caused by blood flow. In this study, we investigated whether shear stress affects the ability of C. albicans to form biofilms. Candida biofilms were formed on catheter discs and exposed to physiological levels of shear stress using a rotating disc system (RDS). Control biofilms were grown under conditions of no flow. Tetrazolium (XTT) assay and dry weight (DW) measurements were used to quantify metabolic activity and biofilm mass respectively. Confocal scanning laser microscopy (CSLM) was used to evaluate architecture and biofilm thickness. After 90 min, cells attached under no-flow exhibited significantly greater XTT activity and DW than those under shear. However, by 24 h, biofilms formed under both conditions had similar XTT activities and DW. Interestingly, thickness of biofilms formed under no-flow was significantly greater after 24 h than of those formed under shear stress, demonstrating that shear exposure results in thinner, but denser biofilms. These studies suggest that biofilm architecture is modulated by shear in a phase-dependent manner. PMID:19076284

  20. Synthesis of Hoodigogenin A, aglycone of natural appetite suppressant glycosteroids extracted from Hoodia gordonii.

    PubMed

    Geoffroy, Philippe; Ressault, Blandine; Marchioni, Eric; Miesch, Michel

    2011-06-01

    14β-hydroxy pregnane glycosides extracted from Hoodia gordonii, a succulent plant isolated from Apocynaceae are suggested to have appetite suppressant properties in animals and humans. However, limited reports on biological studies concerning the appetite suppressant properties are available in the open literature. One reason for that is the poor availability of these glycosteroids because H. gordonii is a protected plant and the yield of extraction lies between 0.003% and 0.02%. Starting from 3α,12α-diacetoxy-pregnanone 1, we disclose in this report the synthesis of Hoodigogenin A, the aglycone of the natural 14β-hydroxy pregnane glycosides extracted from H. Gordonii.

  1. Characterization of Streptococcus gordonii prophage PH15: complete genome sequence and functional analysis of phage-encoded integrase and endolysin.

    PubMed

    van der Ploeg, Jan R

    2008-10-01

    Streptococcus gordonii OMZ1039, isolated from supragingival dental plaque, was found to harbour a prophage, PH15, whose excision could be induced by mitomycin treatment. Phage PH15 belongs to the Siphoviridae. The complete genome sequence of PH15 was determined. The genome was 39 136 bp in size and contained 61 ORFs. The genome of PH15 was most similar in the structural module to the temperate bacteriophages MM1 and phiNIH1.1 from Streptococcus pneumoniae and Streptococcus pyogenes, respectively. In strain OMZ1039, PH15 was found to reside as a prophage in the cysteinyl-tRNA gene. A plasmid, harbouring the attP site and the integrase gene downstream of a constitutive promoter, was capable of site-specific integration into the genomes of different oral streptococcal species. The phage endolysin was purified after expression in Escherichia coli and found to inhibit growth of all S. gordonii strains tested and several different streptococcal species, including the pathogens Streptococcus mutans, S. pyogenes and Streptococcus agalactiae.

  2. Quinone derivatives isolated from the endolichenic fungus Phialocephala fortinii are Mdr1 modulators that combat azole resistance in Candida albicans

    PubMed Central

    Xie, Fei; Chang, Wenqiang; Zhang, Ming; Li, Ying; Li, Wei; Shi, Hongzhuo; Zheng, Sha; Lou, Hongxiang

    2016-01-01

    One of the main azole-resistance mechanisms in Candida pathogens is the upregulation of drug efflux pumps, which compromises the efficacy of azoles and results in treatment failure. The combination of azole-antifungal agents with efflux pump inhibitors represents a promising strategy to combat fungal infection. High-throughput screening of 150 extracts obtained from endolichenic fungal cultures led to the discovery that the extract of Phialocephala fortinii exhibits potent activity for the reversal of azole resistance. From P. fortinii cultures, a total of 15 quinone derivatives, comprising 11 new derivatives and 4 known compounds, were obtained. Among these compounds, palmarumycin P3 (3) and phialocephalarin B (8) specifically modulate the expression of MDR1 to inhibit the activity of drug efflux pumps and therefore reverse azole resistance. The present study revealed Mdr1 targeting as an alternative mechanism for the discovery of new agents to fight antifungal drug resistance. PMID:27650180

  3. Role of Streptococcus gordonii Surface Proteins SspA/SspB and Hsa in Platelet Function▿

    PubMed Central

    Kerrigan, Steven W.; Jakubovics, Nicholas S.; Keane, Ciara; Maguire, Patricia; Wynne, Kieran; Jenkinson, Howard F.; Cox, Dermot

    2007-01-01

    Streptococcus gordonii colonization of damaged heart surfaces in infective endocarditis is dependent upon the recognition of host receptors by specific bacterial surface proteins. However, despite several attempts to identify the mechanisms involved in this interaction, the nature of the bacterial proteins required remains poorly understood. This study provides clear evidence that several S. gordonii surface proteins participate in the interaction with platelets to support platelet adhesion and induce platelet aggregation. S. gordonii strains were found to support strong (DL1-Challis, SK12, SK184, and Blackburn) or moderate (UB1545 Δhsa and CH1-Challis) adhesion or failed to support platelet adhesion (M5, M99, and Channon). In addition, under flow conditions, platelets rolled and subsequently adhered to immobilized S. gordonii at low shear (50 s−1) in an Hsa-dependent manner but did not interact with S. gordonii DL1 at any shear rate of >50 s−1. S. gordonii strains either induced (DL1-Challis, SK12, SK184, UB1545 Δhsa, and M99) or failed to induce (M5, CH1-Challis, Channon, and Blackburn) platelet aggregation. Using a proteomic approach to identify differential cell wall protein expression between aggregating (DL1) and nonaggregating (Blackburn) strains, we identified antigen I/antigen II family proteins SspA and SspB. The overexpression of SspA or SspB in platelet-nonreactive Lactococcus lactis induced GPIIb/GPIIIa-dependent platelet aggregation similar to that seen with S. gordonii DL1. However, they failed to support platelet adhesion. Thus, S. gordonii has distinct mechanisms for supporting platelet adhesion and inducing platelet aggregation. Differential protein expression between strains may be important for the pathogenesis of invasive diseases such as infective endocarditis. PMID:17893126

  4. O-Mannosylation in Candida albicans Enables Development of Interkingdom Biofilm Communities

    PubMed Central

    Dutton, Lindsay C.; Nobbs, Angela H.; Jepson, Katy; Jepson, Mark A.; Vickerman, M. Margaret; Aqeel Alawfi, Sami; Munro, Carol A.; Lamont, Richard J.; Jenkinson, Howard F.

    2014-01-01

    ABSTRACT Candida albicans is a fungus that colonizes oral cavity surfaces, the gut, and the genital tract. Streptococcus gordonii is a ubiquitous oral bacterium that has been shown to form biofilm communities with C. albicans. Formation of dual-species S. gordonii-C. albicans biofilm communities involves interaction of the S. gordonii SspB protein with the Als3 protein on the hyphal filament surface of C. albicans. Mannoproteins comprise a major component of the C. albicans cell wall, and in this study we sought to determine if mannosylation in cell wall biogenesis of C. albicans was necessary for hyphal adhesin functions associated with interkingdom biofilm development. A C. albicans mnt1Δ mnt2Δ mutant, with deleted α-1,2-mannosyltransferase genes and thus defective in O-mannosylation, was abrogated in biofilm formation under various growth conditions and produced hyphal filaments that were not recognized by S. gordonii. Cell wall proteomes of hypha-forming mnt1Δ mnt2Δ mutant cells showed growth medium-dependent alterations, compared to findings for the wild type, in a range of protein components, including Als1, Als3, Rbt1, Scw1, and Sap9. Hyphal filaments formed by mnt1Δ mnt2Δ mutant cells, unlike wild-type hyphae, did not interact with C. albicans Als3 or Hwp1 partner cell wall proteins or with S. gordonii SspB partner adhesin, suggesting defective functionality of adhesins on the mnt1Δ mnt2Δ mutant. These observations imply that early stage O-mannosylation is critical for activation of hyphal adhesin functions required for biofilm formation, recognition by bacteria such as S. gordonii, and microbial community development. PMID:24736223

  5. Involvement of lipoprotein PpiA of Streptococcus gordonii in evasion of phagocytosis by macrophages.

    PubMed

    Cho, K; Arimoto, T; Igarashi, T; Yamamoto, M

    2013-10-01

    Streptococcus gordonii is a commensal gram-positive bacterium that resides in the human oral cavity, and is one of the most common causes of infective endocarditis (IE). Bacterial surface molecules play an important role in establishing IE, and several S. gordonii proteins have been implicated in binding to host cells during the establishment of IE. In this study, we identified a putative lipoprotein, peptidyl-prolyl cis/trans isomerase (PpiA), and clarified its role in evasion of phagocytosis by macrophages. Attenuation of the gene encoding prolipoprotein diacylglyceryl transferase (Lgt) altered the localization of PpiA from the cell surface to the culture supernatant, indicating that PpiA is lipid-anchored in the cell membrane by Lgt. Both human and murine macrophages showed higher phagocytic activity towards ppiA and lgt mutants than the wild-type, indicating that the presence of PpiA suppresses phagocytosis of S. gordonii. Human macrophages treated with dextran sulfate had significantly impaired phagocytosis of S. gordonii, suggesting that class A scavenger receptors in human macrophages are involved in the phagocytosis of S. gordonii. These results provide evidence that S. gordonii lipoprotein PpiA plays an important role in inhibiting phagocytic engulfment and in evasion of the host immune response.

  6. Serine-Rich Repeat Adhesins Contribute to Streptococcus gordonii-Induced Maturation of Human Dendritic Cells

    PubMed Central

    Ko, Eun Byeol; Kim, Sun Kyung; Seo, Ho Seong; Yun, Cheol-Heui; Han, Seung Hyun

    2017-01-01

    Dendritic cells (DCs) play a pivotal role in the induction of immunity by recognition, capture, process, and presentation of antigens from infectious microbes. Streptococcus gordonii is able to cause life-threatening systemic diseases such as infective endocarditis. Serine-rich repeat (SRR) glycoproteins of S. gordonii are sialic acid-binding adhesins mediating the bacterial adherence to the host and the development of infective endocarditis. Thus, the SRR adhesins are potentially involved in the bacterial adherence to DCs and the maturation and activation of DCs required for the induction of immunity to S. gordonii. Here, we investigated the phenotypic and functional changes of human monocyte-derived DCs treated with wild-type S. gordonii or the SRR adhesin-deficient mutant. The mutant poorly bound to DCs and only weakly increased the expression of CD83, CD86, MHC class II, and PD-L1 on DCs compared with the wild-type. In addition, the mutant induced lower levels of TNF-α, IL-6, and IL-12 than the wild-type in DCs. When DCs sensitized with the mutant were co-cultured with autologous T cells, they induced weaker proliferation and activation of T cells than DCs stimulated with the wild-type. Blockade of SRR adhesin with 3′-sialyllactose markedly reduced S. gordonii binding and internalization, causing attenuation of the bacterial immunostimulatory potency in DC maturation. Collectively, our results suggest that SRR adhesins of S. gordonii are important for maturation and activation of DCs.

  7. Modulation of Candida albicans attachment to human epithelial cells by bacteria and carbohydrates.

    PubMed Central

    Centeno, A; Davis, C P; Cohen, M S; Warren, M M

    1983-01-01

    The effects of carbohydrates (mannose and dextrose). Escherichia coli 07KL. and Klebsiella pneumoniae on Candida albicans attachment to epithelial cells was studied. Dextrose had no effect on yeast attachment to epithelial cells. Conversely, mannose significantly decreased both yeast and piliated bacterial attachment (E. coli 07KL, heavily piliated K. pneumoniae) whereas having no effect on nonpiliated K. pneumoniae attachment to epithelial cells. The number of yeasts attaching to epithelial cells was enhanced by preincubation of epithelial cells with piliated strains of bacteria, whereas preincubation with nonpiliated strains of bacteria had no effect on yeast attachment. Scanning electron microscopy showed that piliated bacteria and yeasts were juxtaposed on the epithelial cell surface. These data suggest that certain piliated strains of bacteria can enhance C. albicans attachment to epithelial cells and that type 1 pili of bacteria can be a factor in the enhanced attachment of C. albicans to epithelial cells. Images PMID:6132878

  8. Identification and Differentiation Between Hoodia gordonii Masson) Sweet ex Decne., Opuntia ficus indica (L.) P. Miller and Other Related Hoodia Species by Microscopy and PCR Methods

    Technology Transfer Automated Retrieval System (TEKTRAN)

    H.gordonii an appetite suppressant is used extensively as botanical dietary supplement. Microscopy and molecular genetic procedure are provided for identification and differentiation between H. gordonii, O. ficus-indica and other related Hoodia species.P. ...

  9. Analysis of Candida albicans Mutants Defective in the Cdk8 Module of Mediator Reveal Links between Metabolism and Biofilm Formation

    PubMed Central

    Lindsay, Allia K.; Morales, Diana K.; Liu, Zhongle; Grahl, Nora; Zhang, Anda; Willger, Sven D.; Myers, Lawrence C.; Hogan, Deborah A.

    2014-01-01

    Candida albicans biofilm formation is a key virulence trait that involves hyphal growth and adhesin expression. Pyocyanin (PYO), a phenazine secreted by Pseudomonas aeruginosa, inhibits both C. albicans biofilm formation and development of wrinkled colonies. Using a genetic screen, we identified two mutants, ssn3Δ/Δ and ssn8Δ/Δ, which continued to wrinkle in the presence of PYO. Ssn8 is a cyclin-like protein and Ssn3 is similar to cyclin-dependent kinases; both proteins are part of the heterotetrameric Cdk8 module that forms a complex with the transcriptional co-regulator, Mediator. Ssn3 kinase activity was also required for PYO sensitivity as a kinase dead mutant maintained a wrinkled colony morphology in the presence of PYO. Furthermore, similar phenotypes were observed in mutants lacking the other two components of the Cdk8 module—Srb8 and Srb9. Through metabolomics analyses and biochemical assays, we showed that a compromised Cdk8 module led to increases in glucose consumption, glycolysis-related transcripts, oxidative metabolism and ATP levels even in the presence of PYO. In the mutant, inhibition of respiration to levels comparable to the PYO-treated wild type inhibited wrinkled colony development. Several lines of evidence suggest that PYO does not act through Cdk8. Lastly, the ssn3 mutant was a hyperbiofilm former, and maintained higher biofilm formation in the presence of PYO than the wild type. Together these data provide novel insights into the role of the Cdk8 module of Mediator in regulation of C. albicans physiology and the links between respiratory activity and both wrinkled colony and biofilm development. PMID:25275466

  10. Modulation of Candida albicans virulence by bacterial biofilms on titanium surfaces.

    PubMed

    Cavalcanti, Yuri Wanderley; Wilson, Melanie; Lewis, Michael; Del-Bel-Cury, Altair Antoninha; da Silva, Wander José; Williams, David W

    2016-01-01

    Whilst Candida albicans occurs in peri-implant biofilms, its role in peri-implantitis remains unclear. This study therefore examined the virulence of C. albicans in mixed-species biofilms on titanium surfaces. Biofilms of C. albicans (Ca), C. albicans with streptococci (Streptococcus sanguinis, S. mutans) (Ca-Ss-Sm) and those incorporating Porphyromonas gingivalis (Ca-Pg and Ca-Ss-Sm-Pg) were developed. Expression of C. albicans genes associated with adhesion (ALS1, ALS3, HWP1) and hydrolytic enzymes (SAP2, SAP4, SAP6, PLD1) was measured and hyphal production by C. albicans quantified. Compared with Ca biofilms, significant (p<0.05) up-regulation of ALS3, HWP1, SAP2 and SAP6, and hyphal production occurred in biofilms containing streptococci (Ca-Ss-Sm). In Ca-Pg biofilms, down-regulation of HWP1 and SAP4 expression, with reduced hyphal production occurred. Ca-Ss-Sm-Pg biofilms had increased hyphal proportions and up-regulation of ALS3, SAP2 and SAP6. In conclusion, C. albicans expressed virulence factors in biofilms that could contribute to peri-implantitis, but this was dependent on associated bacterial species.

  11. Mitochondrial Complex V α Subunit Is Critical for Candida albicans Pathogenicity through Modulating Multiple Virulence Properties

    PubMed Central

    Li, Shui-Xiu; Song, Yan-Jun; Zhang, Yi-Shan; Wu, Hao-Tian; Guo, Hui; Zhu, Kun-Ju; Li, Dong-Mei; Zhang, Hong

    2017-01-01

    The α subunit (ATP1) is a vital component of mitochondrial complex V which counts for the majority of cellular ATP production in a living organism. Nevertheless, how the α subunit influences other cellular processes such as pathogenicity in Candida albicans remains poorly understood. To address this question, ATP1 mutant (atp1Δ/Δ) and the gene-reconstituted strain (atp1Δ/ATP1) have been constructed in this study and their pathogenicity-related traits are compared to those of wild type (WT). In a murine model of disseminated candidiasis, atp1Δ/Δ infected mice have a significantly higher survival rate and experience a lower fungal burden in tissues. In in vitro studies atp1Δ/Δ lose a capability to damage or destroy macrophages and endothelial cells. Furthermore, atp1Δ/Δ is not able to grow under either glucose-denial conditions or high H2O2 conditions, both of which are associated with the potency of the macrophages to kill C. albicans. Defects in filamentation and biofilm formation may impair the ability of atp1Δ/Δ to penetrate host cells and establish robust colonies in the host tissues. In concert with these pathogenic features, intracellular ATP levels of atp1Δ/Δ can drop to 1/3 of WT level. These results indicate that the α subunit of Complex V play important roles in C. albicans pathogenicity. PMID:28280492

  12. Characterization of genetic determinants that modulate Candida albicans filamentation in the presence of bacteria.

    PubMed

    Fox, Sean J; Shelton, Bryce T; Kruppa, Michael D

    2013-01-01

    In the human body, fungi and bacteria share many niches where the close contact of these organisms maintains a balance among the microbial population. However, when this microbial balance is disrupted, as with antibiotic treatment, other bacteria or fungi can grow uninhibited. C. albicans is the most common opportunistic fungal pathogen affecting humans and can uniquely control its morphogenesis between yeast, pseudohyphal, and hyphal forms. Numerous studies have shown that C. albicans interactions with bacteria can impact its ability to undergo morphogenesis; however, the genetics that govern this morphological control via these bacterial interactions are still relatively unknown. To aid in the understanding of the cross-kingdom interactions of C. albicans with bacteria and the impact on morphology we utilized a haploinsufficiency based C. albicans mutant screen to test for the ability of C. albicans to produce hyphae in the presence of three bacterial species (Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus). Of the 18,144 mutant strains tested, 295 mutants produced hyphae in the presence of all three bacterial species. The 295 mutants identified 132 points of insertion, which included identified/predicted genes, major repeat sequences, and a number of non-coding/unannotated transcripts. One gene, CDR4, displayed increased expression when co-cultured with S. aureus, but not E. coli or P. aeruginosa. Our data demonstrates the ability to use a large scale library screen to identify genes involved in Candida-bacterial interactions and provides the foundation for comprehending the genetic pathways relating to bacterial control of C. albicans morphogenesis.

  13. Streptococcus mutans Can Modulate Biofilm Formation and Attenuate the Virulence of Candida albicans

    PubMed Central

    Barbosa, Júnia Oliveira; Rossoni, Rodnei Dennis; Vilela, Simone Furgeri Godinho; de Alvarenga, Janaína Araújo; Velloso, Marisol dos Santos; Prata, Márcia Cristina de Azevedo; Jorge, Antonio Olavo Cardoso; Junqueira, Juliana Campos

    2016-01-01

    Streptococcus mutans and Candida albicans are found together in the oral biofilms on dental surfaces, but little is known about the ecological interactions between these species. Here, we studied the effects of S. mutans UA159 on the growth and pathogencity of C. albicans. Initially, the effects of S. mutans on the biofilm formation and morphogenesis of C. albicans were tested in vitro. Next, we investigate the influence of S. mutans on pathogenicity of C. albicans using in vivo host models, in which the experimental candidiasis was induced in G. mellonella larvae and analyzed by survival curves, C. albicans count in hemolymph, and quantification of hyphae in the host tissues. In all the tests, we evaluated the direct effects of S. mutans cells, as well as the indirect effects of the subproducts secreted by this microorganism using a bacterial culture filtrate. The in vitro analysis showed that S. mutans cells favored biofilm formation by C. albicans. However, a reduction in biofilm viable cells and inhibition of hyphal growth was observed when C. albicans was in contact with the S. mutans culture filtrate. In the in vivo study, injection of S. mutans cells or S. mutans culture filtrate into G. mellonella larvae infected with C. albicans increased the survival of these animals. Furthermore, a reduction in hyphal formation was observed in larval tissues when C. albicans was associated with S. mutans culture filtrate. These findings suggest that S. mutans can secrete subproducts capable to inhibit the biofilm formation, morphogenesis and pathogenicity of C. albicans, attenuating the experimental candidiasis in G. mellonella model. PMID:26934196

  14. Streptococcus mutans Can Modulate Biofilm Formation and Attenuate the Virulence of Candida albicans.

    PubMed

    Barbosa, Júnia Oliveira; Rossoni, Rodnei Dennis; Vilela, Simone Furgeri Godinho; de Alvarenga, Janaína Araújo; Velloso, Marisol dos Santos; Prata, Márcia Cristina de Azevedo; Jorge, Antonio Olavo Cardoso; Junqueira, Juliana Campos

    2016-01-01

    Streptococcus mutans and Candida albicans are found together in the oral biofilms on dental surfaces, but little is known about the ecological interactions between these species. Here, we studied the effects of S. mutans UA159 on the growth and pathogencity of C. albicans. Initially, the effects of S. mutans on the biofilm formation and morphogenesis of C. albicans were tested in vitro. Next, we investigate the influence of S. mutans on pathogenicity of C. albicans using in vivo host models, in which the experimental candidiasis was induced in G. mellonella larvae and analyzed by survival curves, C. albicans count in hemolymph, and quantification of hyphae in the host tissues. In all the tests, we evaluated the direct effects of S. mutans cells, as well as the indirect effects of the subproducts secreted by this microorganism using a bacterial culture filtrate. The in vitro analysis showed that S. mutans cells favored biofilm formation by C. albicans. However, a reduction in biofilm viable cells and inhibition of hyphal growth was observed when C. albicans was in contact with the S. mutans culture filtrate. In the in vivo study, injection of S. mutans cells or S. mutans culture filtrate into G. mellonella larvae infected with C. albicans increased the survival of these animals. Furthermore, a reduction in hyphal formation was observed in larval tissues when C. albicans was associated with S. mutans culture filtrate. These findings suggest that S. mutans can secrete subproducts capable to inhibit the biofilm formation, morphogenesis and pathogenicity of C. albicans, attenuating the experimental candidiasis in G. mellonella model.

  15. The alpha-hemolysin of Streptococcus gordonii is hydrogen peroxide.

    PubMed Central

    Barnard, J P; Stinson, M W

    1996-01-01

    The alpha-hemolysin of viridans group streptococci, which causes greening of intact erythrocytes, is a potential virulence factor as well as an important criterion for the laboratory identification of these bacteria; however, it has never been purified and characterized. The alpha-hemolysin of Streptococcus gordonii CH1 caused characteristic shifts in the A403, A430, A578, and A630 of sheep hemoglobin. A spectrophotometric assay was developed and used to monitor purification of alpha-hemolysin during extraction in organic solvents and separation by reverse-phase high-performance liquid chromatography (HPLC). The alpha-hemolysin was identical to hydrogen peroxide with respect to its effects on erythrocyte hemoglobin, oxygen-dependent synthesis by streptococci, insensitivity to proteases, inactivation by catalase, differential solubility, failure to adsorb to ion-exchange chromatography resins, and retention time on a reverse-phase HPLC column. The amount of hydrogen peroxide present in HPLC-fractionated spent culture medium was sufficient to account for all alpha-hemolytic activity observed. PMID:8751938

  16. Candida famata (Candida flareri).

    PubMed

    Dmytruk, Kostyantyn V; Sibirny, Andriy A

    2012-11-01

    Candida famata (Candida flareri) belongs to the group of so-called 'flavinogenic yeasts', capable of riboflavin oversynthesis under condition of iron starvation. Some strains of C. famata belong to the most flavinogenic organisms known and were used for industrial production of riboflavin for a long time in the USA. C. famata is characterized by high salt tolerance, growing at NaCl concentrations of up to 2.5  M. Development of basic tools for the metabolic engineering of C. famata, such as a transformation system, selective markers, insertional mutagenesis, a reporter system and others, are described. The developed tools were used for cloning and identification of structural and regulatory genes of riboflavin synthesis. The construction of improved yeast strains producing riboflavin, FMN and FAD, based on the industrial riboflavin-producing strain dep8 and its non-reverting analogue AF4, is also described.

  17. Cigarette Smoke-Exposed Candida albicans Increased Chitin Production and Modulated Human Fibroblast Cell Responses

    PubMed Central

    Alanazi, Humidah; Semlali, Abdelhabib; Perraud, Laura; Chmielewski, Witold; Zakrzewski, Andrew

    2014-01-01

    The predisposition of cigarette smokers for development of respiratory and oral bacterial infections is well documented. Cigarette smoke can also contribute to yeast infection. The aim of this study was to investigate the effect of cigarette smoke condensate (CSC) on C. albicans transition, chitin content, and response to environmental stress and to examine the interaction between CSC-pretreated C. albicans and normal human gingival fibroblasts. Following exposure to CSC, C. albicans transition from blastospore to hyphal form increased. CSC-pretreated yeast cells became significantly (P < 0.01) sensitive to oxidation but significantly (P < 0.01) resistant to both osmotic and heat stress. CSC-pretreated C. albicans expressed high levels of chitin, with 2- to 8-fold recorded under hyphal conditions. CSC-pretreated C. albicans adhered better to the gingival fibroblasts, proliferated almost three times more and adapted into hyphae, while the gingival fibroblasts recorded a significantly (P < 0.01) slow growth rate but a significantly higher level of IL-1β when in contact with CSC-pretreated C. albicans. CSC was thus able to modulate both C. albicans transition through the cell wall chitin content and the interaction between C. albicans and normal human gingival fibroblasts. These findings may be relevant to fungal infections in the oral cavity in smokers. PMID:25302312

  18. Cigarette smoke-exposed Candida albicans increased chitin production and modulated human fibroblast cell responses.

    PubMed

    Alanazi, Humidah; Semlali, Abdelhabib; Perraud, Laura; Chmielewski, Witold; Zakrzewski, Andrew; Rouabhia, Mahmoud

    2014-01-01

    The predisposition of cigarette smokers for development of respiratory and oral bacterial infections is well documented. Cigarette smoke can also contribute to yeast infection. The aim of this study was to investigate the effect of cigarette smoke condensate (CSC) on C. albicans transition, chitin content, and response to environmental stress and to examine the interaction between CSC-pretreated C. albicans and normal human gingival fibroblasts. Following exposure to CSC, C. albicans transition from blastospore to hyphal form increased. CSC-pretreated yeast cells became significantly (P < 0.01) sensitive to oxidation but significantly (P < 0.01) resistant to both osmotic and heat stress. CSC-pretreated C. albicans expressed high levels of chitin, with 2- to 8-fold recorded under hyphal conditions. CSC-pretreated C. albicans adhered better to the gingival fibroblasts, proliferated almost three times more and adapted into hyphae, while the gingival fibroblasts recorded a significantly (P < 0.01) slow growth rate but a significantly higher level of IL-1β when in contact with CSC-pretreated C. albicans. CSC was thus able to modulate both C. albicans transition through the cell wall chitin content and the interaction between C. albicans and normal human gingival fibroblasts. These findings may be relevant to fungal infections in the oral cavity in smokers.

  19. LuxS-Based Signaling in Streptococcus gordonii: Autoinducer 2 Controls Carbohydrate Metabolism and Biofilm Formation with Porphyromonas gingivalis

    PubMed Central

    McNab, Roderick; Ford, Suzannah K.; El-Sabaeny, Azza; Barbieri, Bruno; Cook, Guy S.; Lamont, Richard J.

    2003-01-01

    Communication based on autoinducer 2 (AI-2) is widespread among gram-negative and gram-positive bacteria, and the AI-2 pathway can control the expression of genes involved in a variety of metabolic pathways and pathogenic mechanisms. In the present study, we identified luxS, a gene responsible for the synthesis of AI-2, in Streptococcus gordonii, a major component of the dental plaque biofilm. S. gordonii conditioned medium induced bioluminescence in an AI-2 reporter strain of Vibrio harveyi. An isogenic mutant of S. gordonii, generated by insertional inactivation of the luxS gene, was unaffected in growth and in its ability to form biofilms on polystyrene surfaces. In contrast, the mutant strain failed to induce bioluminescence in V. harveyi and was unable to form a mixed species biofilm with a LuxS-null strain of the periodontal pathogen Porphyromonas gingivalis. Complementation of the luxS mutation in S. gordonii restored normal biofilm formation with the luxS-deficient P. gingivalis. Differential display PCR demonstrated that the inactivation of S. gordonii luxS downregulated the expression of a number of genes, including gtfG, encoding glucosyltransferase; fruA, encoding extracellular exo-β-d-fructosidase; and lacD encoding tagatose 1,6-diphosphate aldolase. However, S. gordonii cell surface expression of SspA and SspB proteins, previously implicated in mediating adhesion between S. gordonii and P. gingivalis, was unaffected by inactivation of luxS. The results suggest that S. gordonii produces an AI-2-like signaling molecule that regulates aspects of carbohydrate metabolism in the organism. Furthermore, LuxS-dependent intercellular communication is essential for biofilm formation between nongrowing cells of P. gingivalis and S. gordonii. PMID:12486064

  20. Characterization of in Vitro Pharmacokinetic Properties of Hoodigogenin A from Hoodia gordonii

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study was aimed to determine ADME properties of Hoodigogenin A, which is aglycone of oxypregnane steroidal glycoside P57AS3 (P57) isolated from Hoodia gordonii. A series of in vitro assays were used to predict its gastric, intestinal and metabolic stability, intestinal and blood brain barrier (...

  1. Contribution of phosphoglucosamine mutase to the resistance of Streptococcus gordonii DL1 to polymorphonuclear leukocyte killing.

    PubMed

    Yajima, Ayako; Takahashi, Yukihiro; Shimazu, Kisaki; Urano-Tashiro, Yumiko; Uchikawa, Yoshimori; Karibe, Hiroyuki; Konishi, Kiyoshi

    2009-08-01

    Phosphoglucosamine mutase (GlmM; EC 5.4.2.10) catalyzes the interconversion of glucosamine-6-phosphate to glucosamine-1-phosphate, an essential step in the biosynthetic pathway leading to the formation of the peptidoglycan precursor uridine 5'-diphospho-N-acetylglucosamine. We have recently identified the gene (glmM) encoding the enzyme of Streptococcus gordonii, an early colonizer on the human tooth and an important cause of infective endocarditis, and indicated that the glmM mutation in S. gordonii appears to influence bacterial cell growth, morphology, and sensitivity to penicillins. In the present study, we assessed whether the glmM mutation also affects escape from polymorphonuclear leukocyte (PMN)-dependent killing. Although no differences in attachment to human PMNs were observed between the glmM mutant and the wild-type S. gordonii, the glmM mutation resulted in increased sensitivity to PMN-dependent killing. Compared with the wild type, the glmM mutant induced increased superoxide anion production and lysozyme release by PMNs. Moreover, the glmM mutant is more sensitive to lysozyme, indicating that the GlmM may be required for synthesis of firm peptidoglycans for resistance to bacterial cell lysis. These findings suggest that the GlmM contributes to the resistance of S. gordonii to PMN-dependent killing. Enzymes such as GlmM could be novel drug targets for this organism.

  2. Cell Surface Glycoside Hydrolases of Streptococcus gordonii Promote Growth in Saliva

    PubMed Central

    Zhou, Yuan; Zhang, Luxia; Shah, Nehal; Palmer, Robert J.; Cisar, John O.

    2016-01-01

    ABSTRACT The growth of the oral commensal Streptococcus gordonii in saliva may depend on a number of glycoside hydrolases (GHs), including three cell wall-anchored proteins that are homologs of pneumococcal β-galactosidase (BgaA), β-N-acetylglucosaminidase (StrH), and endo-β-N-acetylglucosaminidase D (EndoD). In the present study, we introduced unmarked in-frame deletions into the corresponding genes of S. gordonii DL1, verified the presence (or absence) of the encoded proteins on the resulting mutant strains, and compared these strains with wild-type strain DL1 for growth and glycan foraging in saliva. The overnight growth of wild-type DL1 was reduced 3- to 10-fold by the deletion of any one or two genes and approximately 20-fold by the deletion of all three genes. The only notable change in the salivary proteome associated with this reduction of growth was a downward shift in the apparent molecular masses of basic proline-rich glycoproteins (PRG), which was accompanied by the loss of lectin binding sites for galactose-specific Erythrina cristagalli agglutinin (ECA) and mannose-specific Galanthus nivalis agglutinin (GNA). The binding of ECA to PRG was also abolished in saliva cultures of mutants that expressed cell surface BgaA alone or together with either StrH or EndoD. However, the subsequent loss of GNA binding was seen only in saliva cocultures of different mutants that together expressed all three cell surface GHs. The findings indicate that the growth of S. gordonii DL1 in saliva depends to a significant extent on the sequential actions of first BgaA and then StrH and EndoD on N-linked glycans of PRG. IMPORTANCE The ability of oral bacteria to grow on salivary glycoproteins is critical for dental plaque biofilm development. Little is known, however, about how specific salivary components are attacked and utilized by different members of the biofilm community, such as Streptococcus gordonii. Streptococcus gordonii DL1 has three cell wall

  3. Streptococcus gordonii prosthetic joint infection in the setting of vigorous dental flossing.

    PubMed

    Klein, Rick; Dababneh, Ala S; Palraj, Bharath Raj Varatharaj

    2015-08-11

    A 65-year-old woman with osteoarthritis, who underwent knee replacement 5 years prior, developed sudden onset knee pain and swelling. She had voluntarily starting a vigorous dental flossing regimen prior to the onset of symptoms. The patient underwent right knee arthrotomy, irrigation and debridement of right total knee arthroplasty and exchange of polyethylene with retention of the prosthesis. Intraoperative cultures grew Streptococcus gordonii. She was treated with 6 weeks of ceftriaxone and was later placed on oral antibiotic suppression.

  4. Streptococcus gordonii Biofilm Formation: Identification of Genes that Code for Biofilm Phenotypes

    PubMed Central

    Loo, C. Y.; Corliss, D. A.; Ganeshkumar, N.

    2000-01-01

    Viridans streptococci, which include Streptococcus gordonii, are pioneer oral bacteria that initiate dental plaque formation. Sessile bacteria in a biofilm exhibit a mode of growth that is distinct from that of planktonic bacteria. Biofilm formation of S. gordonii Challis was characterized using an in vitro biofilm formation assay on polystyrene surfaces. The same assay was used as a nonbiased method to screen isogenic mutants generated by Tn916 transposon mutagenesis for defective biofilm formation. Biofilms formed optimally when bacteria were grown in a minimal medium under anaerobic conditions. Biofilm formation was affected by changes in pH, osmolarity, and carbohydrate content of the growth media. Eighteen biofilm-defective mutants of S. gordonii Challis were identified based on Southern hybridization with a Tn916-based probe and DNA sequences of the Tn916-flanking regions. Molecular analyses of these mutants showed that some of the genes required for biofilm formation are involved in signal transduction, peptidoglycan biosynthesis, and adhesion. These characteristics are associated with quorum sensing, osmoadaptation, and adhesion functions in oral streptococci. Only nine of the biofilm-defective mutants had defects in genes of known function, suggesting that novel aspects of bacterial physiology may play a part in biofilm formation. Further identification and characterization of biofilm-associated genes will provide insight into the molecular mechanisms of biofilm formation of oral streptococci. PMID:10671461

  5. Interkingdom cooperation between Candida albicans, Streptococcus oralis and Actinomyces oris modulates early biofilm development on denture material.

    PubMed

    Cavalcanti, Indira M G; Nobbs, Angela H; Ricomini-Filho, Antônio Pedro; Jenkinson, Howard F; Del Bel Cury, Altair A

    2016-04-01

    Candida-associated stomatitis affects up to 60% of denture wearers, and Candida albicans remains the most commonly isolated fungal species. The oral bacteria Actinomyces oris and Streptococcus oralis are abundant in early dental plaque. The aims of this study were to determine the effects of S. oralis and A. oris on the development of C. albicans biofilms on denture material. Resin discs were coated with saliva and at early (1.5 h) or later (24 h) stages of biofilm development, cell numbers of each species were determined. Spatial distribution of microorganisms was visualized by confocal scanning laser microscopy of biofilms labelled by differential fluorescence or by fluorescence in situ hybridization. Interkingdom interactions underpinning biofilm development were also evaluated planktonically utilizing fluorescence microscopy. Synergistic interactions between all three species occurred within biofilms and planktonically. Bacterial cells coaggregated with each other and adhered singly or in coaggregates to C. albicans hyphal filaments. Streptococcus oralis appeared to enhance hyphal filament production and C. albicans biovolume was increased 2-fold. Concomitantly, cell numbers of S. oralis and A. oris were enhanced by C. albicans. Thus, cooperative physical and metabolic processes occurring between these three microbial species intensify pathogenic plaque communities on denture surfaces.

  6. Effect of additional of Hoodia Gordonii and seaweed powder on the sensory and physicochemical properties of brown rice bar

    NASA Astrophysics Data System (ADS)

    Hajal, Masturah Ebni; Ghani, Maaruf Abd; Daud, Norlida Mat

    2015-09-01

    Awareness of the nutritional content of food has increased with the emergence of various health products in the market. Cereal bar is one of the beneficial foods among consumer that concern on their healthy food. This study was conducted to develop a brown rice bar that contain active ingredients (H. gordonii and seaweed powder) and to determine the effect on sensory evaluation and physicochemical properties (colour, texture and proximate analysis) of this product. This study consisted of two phases in which the first phase consisted of development of ten formulations including control. All of the formulations were undergo analysis of colour, texture and sensory evaluation. Based on the sensory evaluation, Control (H. gordonii: 0%, seaweed: 0%) and two best formulations that consist of formulation 6 (H. gordonii: 1.6%; seaweed: 2.8%) and formulation 9 (H. gordonii: 2.4%, seaweed: 2.8%) were chosen to undergo the second phase which is proximate analysis. Base on the result, were significant different (p<0.05) on proximate analysis except for the protein and moisture content. Therefore, it can be concluded that H. gordonii is a good source of fiber when adding in a bar.

  7. Binding of Candida albicans to Human CEACAM1 and CEACAM6 Modulates the Inflammatory Response of Intestinal Epithelial Cells

    PubMed Central

    Müller, Mario M.; Schäfer, Miriam R.; Clauder, Ann-Katrin; Feer, Sabina; Heyl, Kerstin A.; Stock, Magdalena; Klassert, Tilman E.; Zipfel, Peter F.; Singer, Bernhard B.

    2017-01-01

    ABSTRACT Candida albicans colonizes human mucosa, including the gastrointestinal tract, as a commensal. In immunocompromised patients, C. albicans can breach the intestinal epithelial barrier and cause fatal invasive infections. Carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1; CD66a), CEACAM5 (CEA), and CEACAM6 (CD66c) are immunomodulatory receptors expressed on human mucosa and are recruited by bacterial and viral pathogens. Here we show for the first time that a fungal pathogen (i.e., C. albicans) also binds directly to the extracellular domain of human CEACAM1, CEACAM3, CEACAM5, and CEACAM6. Binding was specific for human CEACAMs and mediated by the N-terminal IgV-like domain. In enterocytic C2BBe1 cells, C. albicans caused a transient tyrosine phosphorylation of CEACAM1 and induced higher expression of membrane-bound CEACAM1 and soluble CEACAM6. Lack of the CEACAM1 receptor after short hairpin RNA (shRNA) knockdown abolished CXCL8 (interleukin-8) secretion by C2BBe1 cells in response to C. albicans. In CEACAM1-competent cells, the addition of recombinant soluble CEACAM6 reduced the C. albicans-induced CXCL8 secretion. PMID:28292985

  8. Human Platelets Recognize a Novel Surface Protein, PadA, on Streptococcus gordonii through a Unique Interaction Involving Fibrinogen Receptor GPIIbIIIa▿ †

    PubMed Central

    Petersen, Helen J.; Keane, Ciara; Jenkinson, Howard F.; Vickerman, M. Margaret; Jesionowski, Amy; Waterhouse, Janet C.; Cox, Dermot; Kerrigan, Steven W.

    2010-01-01

    The concept of an infectious agent playing a role in cardiovascular disease is slowly gaining attention. Among several pathogens identified, the oral bacterium Streptococcus gordonii has been implicated as a plausible agent. Platelet adhesion and subsequent aggregation are critical events in the pathogenesis and dissemination of the infective process. Here we describe the identification and characterization of a novel cell wall-anchored surface protein, PadA (397 kDa), of S. gordonii DL1 that binds to the platelet fibrinogen receptor GPIIbIIIa. Wild-type S. gordonii cells induced platelet aggregation and supported platelet adhesion in a GPIIbIIIa-dependent manner. Deletion of the padA gene had no effect on platelet aggregation by S. gordonii but significantly reduced (>75%) platelet adhesion to S. gordonii. Purified N-terminal PadA recombinant polypeptide adhered to platelets. The padA mutant was unaffected in production of other platelet-interactive surface proteins (Hsa, SspA, and SspB), and levels of adherence of the mutant to fetuin or platelet receptor GPIb were unaffected. Wild-type S. gordonii, but not the padA mutant, bound to Chinese hamster ovary cells stably transfected with GPIIbIIIa, and this interaction was ablated by addition of GPIIbIIIa inhibitor Abciximab. These results highlight the growing complexity of interactions between S. gordonii and platelets and demonstrate a new mechanism by which the bacterium could contribute to unwanted thrombosis. PMID:19884334

  9. Candida albicans strain-dependent modulation of pro-inflammatory cytokine release by in vitro oral and vaginal mucosal models.

    PubMed

    Whiley, Robert A; Cruchley, Alan T; Gore, Carelyn; Hagi-Pavli, Eleni

    2012-01-01

    Candida albicans is a commensal organism at several sites and is a versatile, opportunistic pathogen. The underlying factors of pathogen and host associated with commensalism and pathogenicity in C. albicans are complex and their importance is largely unknown. We aimed to study the responses of oral epithelial (OEM) and vaginal epithelial models (VEM) to infection by oral and vaginal C. albicans strains to obtain evidence of inter-strain differences in pathogenicity and of site-specificity. Following inoculation of models, proinflammatory cytokines IL-1α, IL-1β, IL-6, IL-8 and prostaglandin E2 (PGE2) release were monitored and histological staining undertaken. Striking differences in strain behaviour and epithelial responses were observed. IL-1α, IL-1β and IL-8 release were significantly increased from the OEM in response to denture stomatitis strain NCYC 1467. Increased IL-8 release also followed infection of the OEM with both vaginal strains. Overall the VEM was relatively unresponsive to infection with either oral or vaginal strains under these conditions. Adherence and hyphal development were observed for all strains on both models although extensive, uniform tissue penetration was seen only with stomatitis strain NCYC 1467 on the OEM. Candidal strains were assayed for phospholipase (PL) and secreted aspartyl proteinase (SAP) activities where phospholipase (PL) activity was highest for strain NCYC 1467 although highest SAP activity was observed for vaginal strain NCPF 8112 in this assay. This is the first study to concurrently investigate cytokine production from oral and epithelial models using candidal strains originating from these respective mucosal sites from healthy and disease states. These data demonstrate significant differences in inflammatory responses of host epithelia to individual C. albicans strains.

  10. Safety profile of Hoodia gordonii extract: rabbit prenatal developmental toxicity study.

    PubMed

    Dent, M P; Wolterbeek, A P M; Russell, P J; Bradford, R

    2012-01-01

    Hoodia gordonii extract was orally administered by gavage to groups of 22 female New Zealand white rabbits from day 3-28 after mating at doses of 0 (control), 3, 6 or 12 mg/kg bodyweight/day. These doses were reached by a dose escalation phase between days 3 and 7 after mating. As well as a vehicle control group, a control group pair-fed to the high dose was also included. On day 29 after mating the females were euthanized and examined. Treatment at 6 or 12 mg/kg/day was associated with a dose-related reduction in feed intake and bodyweight gain. Feed consumption and bodyweight gain was unaffected at 3mg/kg/day. In spite of marked maternal effects at 12 mg/kg/day, reproductive indices were unaffected at all doses and there were no effects on fetal or placental weights and no morphological changes in the fetuses. The no-observed-effect level (NOEL) for developmental effects was therefore 12 mg/kg/day, and the maternal NOEL was 3mg/kg/day. At doses that caused marked maternal effects, H. gordonii extract did not affect embryonic or fetal development in a species that is considered predictive of developmental toxicity in man.

  11. Hydrogen Peroxide-Dependent DNA Release and Transfer of Antibiotic Resistance Genes in Streptococcus gordonii

    PubMed Central

    Itzek, Andreas; Zheng, Lanyan; Chen, Zhiyun; Merritt, Justin; Kreth, Jens

    2011-01-01

    Certain oral streptococci produce H2O2 under aerobic growth conditions to inhibit competing species like Streptococcus mutans. Additionally, H2O2 production causes the release of extracellular DNA (eDNA). eDNA can participate in several important functions: biofilm formation and cell-cell aggregation are supported by eDNA, while eDNA can serve as a nutrient and as an antimicrobial agent by chelating essential cations. eDNA contains DNA fragments of a size that has the potential to transfer genomic information. By using Streptococcus gordonii as a model organism for streptococcal H2O2 production, H2O2-dependent eDNA release was further investigated. Under defined growth conditions, the eDNA release process was shown to be entirely dependent on H2O2. Chromosomal DNA damage seems to be the intrinsic signal for the release, although only actively growing cells were proficient eDNA donors. Interestingly, the process of eDNA production was found to be coupled with the induction of the S. gordonii natural competence system. Consequently, the production of H2O2 triggered the transfer of antibiotic resistance genes. These results suggest that H2O2 is potentially much more than a simple toxic metabolic by-product; rather, its production could serve as an important environmental signal that facilitates species evolution by transfer of genetic information and an increase in the mutation rate. PMID:21984796

  12. SHIP-1 Couples to the Dectin-1 hemITAM and Selectively Modulates Reactive Oxygen Species Production in Dendritic Cells in Response to Candida albicans.

    PubMed

    Blanco-Menéndez, Noelia; del Fresno, Carlos; Fernandes, Sandra; Calvo, Enrique; Conde-Garrosa, Ruth; Kerr, William G; Sancho, David

    2015-11-01

    Dectin-1 (Clec7a) is a paradigmatic C-type lectin receptor that binds Syk through a hemITAM motif and couples sensing of pathogens such as fungi to induction of innate responses. Dectin-1 engagement triggers a plethora of activating events, but little is known about the modulation of such pathways. Trying to define a more precise picture of early Dectin-1 signaling, we explored the interactome of the intracellular tail of the receptor in mouse dendritic cells. We found unexpected binding of SHIP-1 phosphatase to the phosphorylated hemITAM. SHIP-1 colocalized with Dectin-1 during phagocytosis of zymosan in a hemITAM-dependent fashion. Moreover, endogenous SHIP-1 relocated to live or heat-killed Candida albicans-containing phagosomes in a Dectin-1-dependent manner in GM-CSF-derived bone marrow cells (GM-BM). However, SHIP-1 absence in GM-BM did not affect activation of MAPK or production of cytokines and readouts dependent on NF-κB and NFAT. Notably, ROS production was enhanced in SHIP-1-deficient GM-BM treated with heat-killed C. albicans, live C. albicans, or the specific Dectin-1 agonists curdlan or whole glucan particles. This increased oxidative burst was dependent on Dectin-1, Syk, PI3K, phosphoinositide-dependent protein kinase 1, and NADPH oxidase. GM-BM from CD11c∆SHIP-1 mice also showed increased killing activity against live C. albicans that was dependent on Dectin-1, Syk, and NADPH oxidase. These results illustrate the complexity of myeloid C-type lectin receptor signaling, and how an activating hemITAM can also couple to intracellular inositol phosphatases to modulate selected functional responses and tightly regulate processes such as ROS production that could be deleterious to the host.

  13. Effect of starch and amylase on the expression of amylase-binding protein A in Streptococcus gordonii.

    PubMed

    Nikitkova, A E; Haase, E M; Scannapieco, F A

    2012-08-01

    Streptococcus gordonii is a common oral commensal bacterial species in tooth biofilm (dental plaque) and specifically binds to salivary amylase through the surface exposed amylase-binding protein A (AbpA). When S. gordonii cells are pretreated with amylase, amylase bound to AbpA facilitates growth with starch as a primary nutrition source. The goal of this study was to explore possible regulatory effects of starch, starch metabolites and amylase on the expression of S. gordonii AbpA. An amylase ligand-binding assay was used to assess the expression of AbpA in culture supernatants and on bacterial cells from S. gordonii grown in defined medium supplemented with 1% starch, 0.5 mg ml(-1) amylase, with starch and amylase together, or with various linear malto-oligosaccharides. Transcription of abpA was determined by reverse transcription quantitative polymerase chain reaction. AbpA was not detectable in culture supernatants containing either starch alone or amylase alone. In contrast, the amount of AbpA was notably increased when starch and amylase were both present in the medium. The expression of abpA was significantly increased (P < 0.05) following 40 min of incubation in defined medium supplemented with starch and amylase. Similar results were obtained in the presence of maltose and other short-chain malto-oligosacchrides. These results suggest that the products of starch hydrolysis produced from the action of salivary α-amylase, particularly maltose and maltotriose, up-regulate AbpA expression in S. gordonii.

  14. Structural and dynamical aspects of Streptococcus gordonii FabH through molecular docking and MD simulations.

    PubMed

    Shamim, Amen; Abbasi, Sumra Wajid; Azam, Syed Sikander

    2015-07-01

    β-Ketoacyl-ACP-synthase III (FabH or KAS III) has become an attractive target for the development of new antibacterial agents which can overcome the multidrug resistance. Unraveling the fatty acid biosynthesis (FAB) metabolic pathway and understanding structural coordinates of FabH will provide valuable insights to target Streptococcus gordonii for curing oral infection. In this study, we designed inhibitors against therapeutic target FabH, in order to block the FAB pathway. As compared to other targets, FabH has more interactions with other proteins, located on the leading strand with higher codon adaptation index value and associated with lipid metabolism category of COG. Current study aims to gain in silico insights into the structural and dynamical aspect of S. gordonii FabH via molecular docking and molecular dynamics (MD) simulations. The FabH protein is catalytically active in dimerization while it can lock in monomeric state. Current study highlights two residues Pro88 and Leu315 that are close to each other by dimerization. The active site of FabH is composed of the catalytic triad formed by residues Cys112, His249, and Asn279 in which Cys112 is involved in acetyl transfer, while His249 and Asn279 play an active role in decarboxylation. Docking analysis revealed that among the studied compounds, methyl-CoA disulfide has highest GOLD score (82.75), binding affinity (-11 kcal/mol) and exhibited consistently better interactions. During MD simulations, the FabH structure remained stable with the average RMSD value of 1.7 Å and 1.6 Å for undocked protein and docked complex, respectively. Further, crucial hydrogen bonding of the conserved catalytic triad for exhibiting high affinity between the FabH protein and ligand is observed by RDF analysis. The MD simulation results clearly demonstrated that binding of the inhibitor with S. gordonii FabH enhanced the structure and stabilized the dimeric FabH protein. Therefore, the inhibitor has the potential to become

  15. Plantar Purpura as the Initial Presentation of Viridians Streptococcal Shock Syndrome Secondary to Streptococcus gordonii Bacteremia

    PubMed Central

    Liao, Chen-Yi; Su, Kuan-Jen; Lin, Cheng-Hui; Huang, Shu-Fang; Chin, Hsien-Kuo; Chang, Chin-Wen; Kuo, Wu-Hsien; Ben, Ren-Jy; Yeh, Yen-Cheng

    2016-01-01

    Viridians streptococcal shock syndrome is a subtype of toxic shock syndrome. Frequently, the diagnosis is missed initially because the clinical features are nonspecific. However, it is a rapidly progressive disease, manifested by hypotension, rash, palmar desquamation, and acute respiratory distress syndrome within a short period. The disease course is generally fulminant and rarely presents initially as a purpura over the plantar region. We present a case of a 54-year-old female hospital worker diagnosed with viridians streptococcal shock syndrome caused by Streptococcus gordonii. Despite aggressive antibiotic treatment, fluid hydration, and use of inotropes and extracorporeal membrane oxygenation, the patient succumbed to the disease. Early diagnosis of the potentially fatal disease followed by a prompt antibiotic regimen and appropriate use of steroids are cornerstones in the management of this disease to reduce the risk of high morbidity and mortality. PMID:27366188

  16. Calcium-binding properties of SSP-5, the Streptococcus gordonii M5 receptor for salivary agglutinin.

    PubMed

    Duan, Y; Fisher, E; Malamud, D; Golub, E; Demuth, D R

    1994-12-01

    Streptococcus gordonii M5 expresses a lectin on its surface (SSP-5) which binds to human salivary agglutinin (SAG). This interaction requires sialic acid residues of SAG and divalent cations and may mediate the colonization of oral tissues by this organism. In this report, we show that the binding of SAG to SSP-5 requires calcium and that SSP-5 is a high-affinity calcium-binding protein. SAG-mediated aggregation of S. gordonii M5 was inhibited by 1 mM EDTA, and the restoration of aggregation occurred only upon the readdition of calcium. To ascertain the level at which calcium exerts its effects, the calcium-binding properties of SSP-5 were evaluated by using a 45Ca binding assay. In addition, a kinetic analysis of calcium binding was carried out by using fura2, a fluorescent calcium-binding dye. These analyses showed that SSP-5 is a high-affinity calcium-binding protein that binds 1 mol of calcium per mol of protein and has a dissociation constant of 0.45 +/- 0.2 microM. The calcium-binding capacity of SSP-5 was also calculated independently to be 1.0 +/- 0.2 mol of Ca per mol of SSP-5 by column chromatography on Sephadex G-25 equilibrated with 10 microM 45Ca. To localize the calcium binding site of SSP-5, a series of C-terminal deletion mutants were expressed in Escherichia coli and evaluated for calcium-binding activity. Deletion of the 250 C-terminal residues of SSP-5 had little effect on calcium binding. However, deletion of residues 1168 to 1250 resulted in the loss of calcium-binding activity, suggesting that this region is important for calcium binding by SSP-5.

  17. Antimicrobial decapeptide KSL-W attenuates Candida albicans virulence by modulating its effects on Toll-like receptor, human β-defensin, and cytokine expression by engineered human oral mucosa.

    PubMed

    Semlali, A; Leung, K P; Curt, S; Rouabhia, M

    2011-05-01

    We investigated the toxicity of synthetic antimicrobial decapeptide KSL-W on normal human gingival epithelial cell cultures, its effect on Candida albicans adhesion and growth, and the activation of epithelial cell innate immunity. Our results indicate that KSL-W had no toxic effect on cell adhesion or growth, suggesting its safe use with human cells. Pre-treating C. albicans with KSL-W attenuated the yeast's virulence as demonstrated by its reduced adhesion and growth on engineered human oral mucosa epithelium and the subsequent decreased expression of some innate defense molecules by targeted epithelial cells. Indeed, the expression of Toll-like receptors and human β-defensins was reduced in tissues infected with KSL-W-treated Candida. Proinflammatory cytokine secretion (IL-1β and IL-6) by the epithelial cells was also regulated by KSL-W in a manner similar to that of antifungal molecule amphotericin B. These findings therefore show that KSL-W is safe for use with human cells and is able to attenuate Candida virulence by modulating its effects on host innate immunity. This study proposes the potential application of KSL-W peptide as an alternative antifungal agent.

  18. Structural dissection and in vivo effectiveness of a peptide inhibitor of Porphyromonas gingivalis adherence to Streptococcus gordonii.

    PubMed

    Daep, Carlo Amorin; Novak, Elizabeth A; Lamont, Richard J; Demuth, Donald R

    2011-01-01

    The interaction of the minor fimbrial antigen (Mfa) with streptococcal antigen I/II (e.g., SspB) facilitates colonization of the dental biofilm by Porphyromonas gingivalis. We previously showed that a 27-mer peptide derived from SspB (designated BAR) resembles the nuclear receptor (NR) box protein-protein interacting domain and potently inhibits this interaction in vitro. Here, we show that the EXXP motif upstream of the NR core α-helix contributes to the Mfa-SspB interaction and that BAR reduces P. gingivalis colonization and alveolar bone loss in vivo in a murine model of periodontitis. Substitution of Gln for Pro(1171) or Glu(1168) increased the α-helicity of BAR and reduced its inhibitory activity in vitro by 10-fold and 2-fold, respectively. To determine if BAR prevents P. gingivalis infection in vivo, mice were first infected with Streptococcus gordonii and then challenged with P. gingivalis in the absence and presence of BAR. Animals that were infected with either 10(9) CFU of S. gordonii DL-1 or 10(7) CFU of P. gingivalis 33277 did not show a statistically significant increase in alveolar bone resorption over sham-infected controls. However, infection with 10(9) CFU of S. gordonii followed by 10(7) CFU of P. gingivalis induced significantly greater bone loss (P < 0.01) than sham infection or infection of mice with either organism alone. S. gordonii-infected mice that were subsequently challenged with 10(7) CFU of P. gingivalis in the presence of BAR exhibited levels of bone resorption similar to those of sham-infected animals. Together, these results indicate that both EXXP and the NR box are important for the Mfa-SspB interaction and that BAR peptide represents a potential therapeutic that may limit colonization of the oral cavity by P. gingivalis.

  19. The two-component system BfrAB regulates expression of ABC transporters in Streptococcus gordonii and Streptococcus sanguinis

    PubMed Central

    Zhang, Yongshu; Whiteley, Marvin; Kreth, Jens; Lei, Yu; Khammanivong, Ali; Evavold, Jamie N.; Fan, Jingyuan; Herzberg, Mark C.

    2009-01-01

    The putative two-component system BfrAB is involved in Streptococcus gordonii biofilm development. Here, we provide evidence that BfrAB regulates the expression of bfrCD and bfrEFG, which encode two ABC transporters, and bfrH, which encodes a CAAX amino-terminal protease family protein. BfrC and BfrE are ATP-binding proteins and BfrD, BfrF and BfrG are homologous membrane- spanning polypeptides. Similarly, BfrABss, the BfrAB homologous system in S. sanguinis controls the expression of two bfrCD-homologous operons (bfrCDss and bfrXYss), a bfrH-homologous gene (bfrH1ss) and another CAAX amino- terminal protease family protein gene (bfrH2ss). Furthermore, we demonstrate that the purified BfrA DNA-binding domain from S. gordonii binds to the promoter regions of bfrCD, bfrEFG, bfrH, bfrCDss, bfrXYss, and bfrH1ss in vitro. Finally, we show that the BfrA DNA-binding domain recognizes a conserved DNA motif with a consensuses sequence of TTTCTTTAGAAATATTTTAGAATT. These data suggest, therefore, that S. gordonii BfrAB could control biofilm formation by regulating multiple ABC-transporter systems. PMID:19118357

  20. Candida, fluorescent stain (image)

    MedlinePlus

    This microscopic film shows 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 ...

  1. Antidepressant-like effect of Hoodia gordonii in a forced swimming test in mice: evidence for involvement of the monoaminergic system

    PubMed Central

    Citó, M.C.O.; Silva, M.I.G.; Santos, L.K.X.; Fernandes, M.L.; Melo, F.H.C.; Aguiar, J.A.C.; Lopes, I.S.; Sousa, P.B.; Vasconcelos, S.M.M.; Macêdo, D.S.; Sousa, F.C.F.

    2014-01-01

    Hoodia gordonii is a plant species used traditionally in southern Africa to suppress appetite. Recently, it has been associated with a significant increase in blood pressure and pulse rate in women, suggesting sympathomimetic activity. The present study investigated the possible antidepressant-like effects of acute and repeated (15 days) administration of H. gordonii extract (25 and 50 mg/kg, po) to mice exposed to a forced swimming test (FST). Neurochemical analysis of brain monoamines was also carried out to determine the involvement of the monoaminergic system on these effects. Acute administration of H. gordonii decreased the immobility of mice in the FST without accompanying changes in general activity in the open-field test during acute treatment, suggesting an antidepressant-like effect. The anti-immobility effect of H. gordonii was prevented by pretreatment of mice with PCPA [an inhibitor of serotonin (5-HT) synthesis], NAN-190 (a 5-HT1A antagonist), ritanserin (a 5-HT2A/2C antagonist), ondansetron (a 5-HT3A antagonist), prazosin (an α1-adrenoceptor antagonist), SCH23390 (a D1 receptor antagonist), yohimbine (an α2-adrenoceptor antagonist), and sulpiride (a D2 receptor antagonist). A significant increase in 5-HT levels in the striatum was detected after acute administration, while 5-HT, norepinephrine and dopamine were significantly elevated after chronic treatment. Results indicated that H. gordonii possesses antidepressant-like activity in the FST by altering the dopaminergic, serotonergic, and noradrenergic systems. PMID:25493384

  2. Regulation of Gene Expression in a Mixed-Genus Community: Stabilized Arginine Biosynthesis in Streptococcus gordonii by Coaggregation with Actinomyces naeslundii▿

    PubMed Central

    Jakubovics, Nicholas S.; Gill, Steven R.; Iobst, Stacey E.; Vickerman, M. M.; Kolenbrander, Paul E.

    2008-01-01

    Interactions involving genetically distinct bacteria, for example, between oral streptococci and actinomyces, are central to dental plaque development. A DNA microarray identified Streptococcus gordonii genes regulated in response to coaggregation with Actinomyces naeslundii. The expression of 23 genes changed >3-fold in coaggregates, including that of 9 genes involved in arginine biosynthesis and transport. The capacity of S. gordonii to synthesize arginine was assessed using a chemically defined growth medium. In monoculture, streptococcal arginine biosynthesis was inefficient and streptococci could not grow aerobically at low arginine concentrations. In dual-species cultures containing coaggregates, however, S. gordonii grew to high cell density at low arginine concentrations. Equivalent cocultures without coaggregates showed no growth until coaggregation was evident (9 h). An argH mutant was unable to grow at low arginine concentrations with or without A. naeslundii, indicating that arginine biosynthesis was essential for coaggregation-induced streptococcal growth. Using quantitative reverse transcriptase PCR, the expression of argC, argG, and pyrAb was strongly (10- to 100-fold) up-regulated in S. gordonii monocultures after 3 h of growth when exogenous arginine was depleted. Cocultures without induced coaggregation showed similar regulation. However, within 1 h after coaggregation with A. naeslundii, the expression of argC, argG, and pyrAb in S. gordonii was partially up-regulated although arginine was plentiful, and mRNA levels did not increase further when arginine was diminished. Thus, A. naeslundii stabilizes S. gordonii expression of arginine biosynthesis genes in coaggregates but not cocultures and enables aerobic growth when exogenous arginine is limited. PMID:18359813

  3. Identification and characterization of a novel Fusobacterium nucleatum adhesin involved in physical interaction and biofilm formation with Streptococcus gordonii.

    PubMed

    Lima, Bruno P; Shi, Wenyuan; Lux, Renate

    2017-02-07

    To successfully colonize the oral cavity, bacteria must directly or indirectly adhere to available oral surfaces. Fusobacterium nucleatum plays an important role in oral biofilm community development due to its broad adherence abilities, serving as a bridge between members of the oral biofilm that cannot directly bind to each other. In our efforts to characterize the molecular mechanisms utilized by F. nucleatum to physically bind to key members of the oral community, we investigated the involvement of F. nucleatum outer membrane proteins in its ability to bind to the pioneer biofilm colonizer, Streptococcus gordonii. Here, we present evidence that in addition to the previously characterized fusobacterial adhesin RadD, the interaction between F. nucleatum ATCC 23726 and S. gordonii V288 involves a second outer membrane protein, which we named coaggregation mediating protein A (CmpA). We also characterized the role of CmpA in dual-species biofilm formation with S. gordonii V288, evaluated growth-phase-dependent as well as biofilm expression profiles of radD and cmpA, and confirmed an important role for CmpA, especially under biofilm growth conditions. Our findings underscore the complex set of specific interactions involved in physical binding and thus community integration of interacting bacterial species. This complex set of interactions could have critical implications for the formation and maturation of the oral biofilms in vivo, and could provide clues to the mechanism behind the distribution of organisms inside the human oral cavity.

  4. The Streptococcus gordonii Adhesin CshA Protein Binds Host Fibronectin via a Catch-Clamp Mechanism*♦

    PubMed Central

    Back, Catherine R.; Sztukowska, Maryta N.; Till, Marisa; Lamont, Richard J.; Jenkinson, Howard F.; Nobbs, Angela H.; Race, Paul R.

    2017-01-01

    Adherence of bacteria to biotic or abiotic surfaces is a prerequisite for host colonization and represents an important step in microbial pathogenicity. This attachment is facilitated by bacterial adhesins at the cell surface. Because of their size and often elaborate multidomain architectures, these polypeptides represent challenging targets for detailed structural and functional characterization. The multifunctional fibrillar adhesin CshA, which mediates binding to both host molecules and other microorganisms, is an important determinant of colonization by Streptococcus gordonii, an oral commensal and opportunistic pathogen of animals and humans. CshA binds the high-molecular-weight glycoprotein fibronectin (Fn) via an N-terminal non-repetitive region, and this protein-protein interaction has been proposed to promote S. gordonii colonization at multiple sites within the host. However, the molecular details of how these two proteins interact have yet to be established. Here we present a structural description of the Fn binding N-terminal region of CshA, derived from a combination of X-ray crystallography, small angle X-ray scattering, and complementary biophysical methods. In vitro binding studies support a previously unreported two-state “catch-clamp” mechanism of Fn binding by CshA, in which the disordered N-terminal domain of CshA acts to “catch” Fn, via formation of a rapidly assembled but also readily dissociable pre-complex, enabling its neighboring ligand binding domain to tightly clamp the two polypeptides together. This study presents a new paradigm for target binding by a bacterial adhesin, the identification of which will inform future efforts toward the development of anti-adhesive agents that target S. gordonii and related streptococci. PMID:27920201

  5. Structure of amylase-binding protein A of Streptococcus gordonii: a potential receptor for human salivary α-amylase enzyme.

    PubMed

    Sethi, Ashish; Mohanty, Biswaranjan; Ramasubbu, Narayanan; Gooley, Paul R

    2015-06-01

    Amylase-binding protein A (AbpA) of a number of oral streptococci is essential for the colonization of the dental pellicle. We have determined the solution structure of residues 24-195 of AbpA of Streptococcus gordonii and show a well-defined core of five helices in the region of 45-115 and 135-145. (13) Cα/β chemical shift and heteronuclear (15) N-{(1) H} NOE data are consistent with this fold and that the remainder of the protein is unstructured. The structure will inform future molecular experiments in defining the mechanism of human salivary α-amylase binding and biofilm formation by streptococci.

  6. Herpes Simplex Virus (HSV) Modulation of Staphylococcus aureus and Candida albicans Initiation of HeLa 299 Cell-Associated Biofilm.

    PubMed

    Plotkin, Balbina J; Sigar, Ira M; Tiwari, Vaibhav; Halkyard, Scott

    2016-05-01

    Although herpes simplex virus type-1 (HSV-1), and type-2 (HSV-2), Staphylococcus aureus and Candida albicans co-habit the oral and genital mucosa, their interaction is poorly understood. We determined the effect HSV has on bacterial and/or fungal adherence, the initial step in biofilm formation. HeLa229 cells were infected with HSV-1 (KOS) gL86 or HSV-2 (KOS) 333gJ (-) at a multiplicity of infection (MOI) of 50 and 10. S. aureus (ATCC 25923) and/or C. albicans (yeast forms or germ tube forms) were co-incubated for 30 min (37 °C; 5 % CO2; 5:1 organism: HeLa cell ratio; n = 16) with virus-infected HeLa cells or uninfected HeLa cell controls. Post-incubation, the monolayers were washed (3x; PBS), lysed (RIPA), and the lysate plated onto Fungisel and/or mannitol salts agar for standard colony count. The level of HeLa-associated S. aureus was significantly decreased (P < 0.05) for both HSV-1- and HSV-2-infected cells, as compared to virus-free HeLa cell controls (38 and 59 % of control, respectively). In contrast, HSV-1 and HSV-2 significantly (P < 0.05) enhanced HeLa cell association of C. albicans yeast forms and germ tube approximately two-fold, respectively. The effect of S. aureus on germ tube and yeast form adherence to HSV-1- and HSV-2-infected cells was specific for the Candida phenotype tested. Our study suggests that HSV, while antagonist towards S. aureus adherence enhances Candida adherence. Furthermore, the combination of the three pathogens results in S. aureus adherence that is either unaffected, or partially restored depending on both the herpes viral species and the fungal phenotype present.

  7. Antimicrobial Effect of Lactobacillus reuteri on Cariogenic Bacteria Streptococcus gordonii, Streptococcus mutans, and Periodontal Diseases Actinomyces naeslundii and Tannerella forsythia.

    PubMed

    Baca-Castañón, Magda Lorena; De la Garza-Ramos, Myriam Angélica; Alcázar-Pizaña, Andrea Guadalupe; Grondin, Yohann; Coronado-Mendoza, Anahí; Sánchez-Najera, Rosa Isela; Cárdenas-Estrada, Eloy; Medina-De la Garza, Carlos Eduardo; Escamilla-García, Erandi

    2015-03-01

    Lactic acid bacteria (LAB) are well known for their beneficial effects on human health in the intestine and immune system; however, there are few studies on the impact they can generate in oral health. The aim of this study was to test and compare in vitro antimicrobial activity of L. reuteri on pathogenic bacteria involved in the formation of dental caries: S. mutans, S. gordonii, and periodontal disease: A. naeslundii and T. forsythia. Also, we determined the growth kinetics of each bacterium involved in this study. Before determining the antimicrobial action of L. reuteri on cariogenic bacteria and periodontal disease, the behavior and cell development time of each pathogenic bacterium were studied. Once the conditions for good cell growth of each of selected pathogens were established according to their metabolic requirements, maximum exponential growth was determined, this being the reference point for analyzing the development or inhibition by LAB using the Kirby Bauer method. Chlorhexidine 0.12% was positive control. L. reuteri was shown to have an inhibitory effect against S. mutans, followed by T. forsythia and S. gordonii, and a less significant effect against A. naeslundii. Regarding the effect shown by L. reuteri on the two major pathogens, we consider its potential use as a possible functional food in the prevention or treatment of oral diseases.

  8. Candida Infective Endocarditis

    PubMed Central

    Baddley, John W.; Benjamin, Daniel K.; Patel, Mukesh; Miró, José; Athan, Eugene; Barsic, Bruno; Bouza, Emilio; Clara, Liliana; Elliott, Tom; Kanafani, Zeina; Klein, John; Lerakis, Stamatios; Levine, Donald; Spelman, Denis; Rubinstein, Ethan; Tornos, Pilar; Morris, Arthur J.; Pappas, Paul; Fowler, Vance G.; Chu, Vivian H.; Cabell, Christopher

    2009-01-01

    Purpose Candida infective endocarditis (IE) is uncommon but often fatal. Most epidemiologic data are derived from small case series or case reports. This study was conducted to explore epidemiology, treatment patterns, and outcomes of patients with Candida IE. Methods We compared 33 Candida IE cases to 2716 patients with non-fungal IE in the International Collaboration on Endocarditis - Prospective Cohort Study. Patients were enrolled and data collected from June 2000 until August 2005. Results Patients with Candida IE were more likely to have prosthetic valves (p<0.001), short term indwelling catheters (p<0.0001), and have healthcare-associated infection (p<0.001). Reasons for surgery differed between the two groups: myocardial abscess (46.7% vs. 22.2% p=0.026) and persistent positive blood cultures (33.3% vs. 9.9%, p=0.003) were more common among those with Candida IE. Mortality at discharge was higher in patients with Candida IE (30.3%) when compared to non-fungal cases (17%, p=0.046). Among Candida patients, mortality was similar in patients who received combination surgical and antifungal therapy versus antifungal therapy alone (33.3% vs. 27.8%, p=0.26). New antifungal drugs, particularly echinocandins, were used frequently. Conclusions These multi-center data suggest distinct epidemiologic features of Candida IE when compared to non-fungal cases. Indications for surgical intervention are different and mortality is increased. Newer antifungal treatment options are increasingly used. Large, multi-center studies are needed to help better define Candida IE. PMID:18283504

  9. Candida infective endocarditis.

    PubMed

    Baddley, J W; Benjamin, D K; Patel, M; Miró, J; Athan, E; Barsic, B; Bouza, E; Clara, L; Elliott, T; Kanafani, Z; Klein, J; Lerakis, S; Levine, D; Spelman, D; Rubinstein, E; Tornos, P; Morris, A J; Pappas, P; Fowler, V G; Chu, V H; Cabell, C

    2008-07-01

    Candida infective endocarditis (IE) is uncommon but often fatal. Most epidemiologic data are derived from small case series or case reports. This study was conducted to explore the epidemiology, treatment patterns, and outcomes of patients with Candida IE. We compared 33 Candida IE cases to 2,716 patients with non-fungal IE in the International Collaboration on Endocarditis-Prospective Cohort Study (ICE-PCS). Patients were enrolled and the data collected from June 2000 until August 2005. We noted that patients with Candida IE were more likely to have prosthetic valves (p < 0.001), short-term indwelling catheters (p < 0.0001), and have healthcare-associated infections (p < 0.001). The reasons for surgery differed between the two groups: myocardial abscess (46.7% vs. 22.2%, p = 0.026) and persistent positive blood cultures (33.3% vs. 9.9%, p = 0.003) were more common among those with Candida IE. Mortality at discharge was higher in patients with Candida IE (30.3%) when compared to non-fungal cases (17%, p = 0.046). Among Candida patients, mortality was similar in patients who received combination surgical and antifungal therapy versus antifungal therapy alone (33.3% vs. 27.8%, p = 0.26). New antifungal drugs, particularly echinocandins, were used frequently. These multi-center data suggest distinct epidemiologic features of Candida IE when compared to non-fungal cases. Indications for surgical intervention are different and mortality is increased. Newer antifungal treatment options are increasingly used. Large, multi-center studies are needed to help better define Candida IE.

  10. Krüppel-like Factor 4 modulates interleukin-6 release in human dendritic cells after in vitro stimulation with Aspergillus fumigatus and Candida albicans

    PubMed Central

    Czakai, Kristin; Leonhardt, Ines; Dix, Andreas; Bonin, Michael; Linde, Joerg; Einsele, Hermann; Kurzai, Oliver; Loeffler, Jürgen

    2016-01-01

    Invasive fungal infections are associated with high mortality rates and are mostly caused by the opportunistic fungi Aspergillus fumigatus and Candida albicans. Immune responses against these fungi are still not fully understood. Dendritic cells (DCs) are crucial players in initiating innate and adaptive immune responses against fungal infections. The immunomodulatory effects of fungi were compared to the bacterial stimulus LPS to determine key players in the immune response to fungal infections. A genome wide study of the gene regulation of human monocyte-derived dendritic cells (DCs) confronted with A. fumigatus, C. albicans or LPS was performed and Krüppel-like factor 4 (KLF4) was identified as the only transcription factor that was down-regulated in DCs by both fungi but induced by stimulation with LPS. Downstream analysis demonstrated the influence of KLF4 on the interleukine-6 expression in human DCs. Furthermore, KLF4 regulation was shown to be dependent on pattern recognition receptor ligation. Therefore KLF4 was identified as a controlling element in the IL-6 immune response with a unique expression pattern comparing fungal and LPS stimulation. PMID:27346433

  11. Modulation of Phagosomal pH by Candida albicans Promotes Hyphal Morphogenesis and Requires Stp2p, a Regulator of Amino Acid Transport

    PubMed Central

    Vylkova, Slavena; Lorenz, Michael C.

    2014-01-01

    Candida albicans, the most important fungal pathogen of humans, has a unique interaction with macrophages in which phagocytosis induces a switch from the yeast to hyphal form, allowing it to escape by rupturing the immune cell. While a variety of factors induce this switch in vitro, including neutral pH, it is not clear what triggers morphogenesis within the macrophage where the acidic environment should inhibit this transition. In vitro, C. albicans grown in similar conditions in which amino acids are the primary carbon source generate large quantities of ammonia to raise the extracellular pH and induce the hyphal switch. We show here that C. albicans cells neutralize the macrophage phagosome and that neutral pH is a key inducer of germination in phagocytosed cells by using a mutant lacking STP2, a transcription factor that regulates the expression of multiple amino acid permeases, that is completely deficient in alkalinization in vitro. Phagocytosed stp2Δ mutant cells showed significant reduction in hypha formation and escaped from macrophages less readily compared to wild type cells; as a result stp2Δ mutant cells were killed at a higher rate and caused less damage to RAW264.7 macrophages. Stp2p-regulated import leads to alkalinization of the phagosome, since the majority of the wild type cells fail to co-localize with acidophilic dyes, whereas the stp2Δ mutant cells were located in acidic phagosomes. Furthermore, stp2Δ mutant cells were able to form hyphae and escape from neutral phagosomes, indicating that the survival defect in these cells was pH dependent. Finally, these defects are reflected in an attenuation of virulence in a mouse model of disseminated candidiasis. Altogether our results suggest that C. albicans utilizes amino acids to promote neutralization of the phagosomal pH, hyphal morphogenesis, and escape from macrophages. PMID:24626429

  12. Mutation of the Streptococcus gordonii Thiol-Disulfide Oxidoreductase SdbA Leads to Enhanced Biofilm Formation Mediated by the CiaRH Two-Component Signaling System

    PubMed Central

    Davey, Lauren; Halperin, Scott A.; Lee, Song F.

    2016-01-01

    Streptococcus gordonii is a commensal inhabitant of human oral biofilms. Previously, we identified an enzyme called SdbA that played an important role in biofilm formation by S. gordonii. SdbA is thiol-disulfide oxidoreductase that catalyzes disulfide bonds in secreted proteins. Surprisingly, inactivation of SdbA results in enhanced biofilm formation. In this study we investigated the basis for biofilm formation by the ΔsdbA mutant. The results revealed that biofilm formation was mediated by the interaction between the CiaRH and ComDE two-component signalling systems. Although it did not affect biofilm formation by the S. gordonii parent strain, CiaRH was upregulated in the ΔsdbA mutant and it was essential for the enhanced biofilm phenotype. The biofilm phenotype was reversed by inactivation of CiaRH or by the addition of competence stimulating peptide, the production of which is blocked by CiaRH activity. Competition assays showed that the enhanced biofilm phenotype also corresponded to increased oral colonization in mice. Thus, the interaction between SdbA, CiaRH and ComDE affects biofilm formation both in vitro and in vivo. PMID:27846284

  13. Molecular Epidemiology of Candida albicans and Its Closely Related Yeasts Candida dubliniensis and Candida africana▿

    PubMed Central

    Romeo, Orazio; Criseo, Giuseppe

    2009-01-01

    We performed a molecular study to determine the occurrence of Candida albicans, Candida africana, and Candida dubliniensis in different clinical samples. The study provides new insights into the epidemiology of candidiasis in hospitalized patients in three hospitals in southern Italy. It also reports the first detailed epidemiological data concerning the occurrence of C. africana in clinical samples. PMID:18987171

  14. Description of Groenewaldozyma gen. nov. for placement of Candida auringiensis, Candida salmanticensis and Candida tartarivorans

    Technology Transfer Automated Retrieval System (TEKTRAN)

    DNA sequence analyses have demonstrated that species of the polyphyletic anamorphic ascomycete genus Candida may be members of described teleomorphic genera, members of the Candida tropicalis clade upon which the genus Candida is circumscribed, or members of isolated clades that represent undescribe...

  15. Performance of Candida ID, a New Chromogenic Medium for Presumptive Identification of Candida Species, in Comparison to CHROMagar Candida

    PubMed Central

    Willinger, Birgit; Hillowoth, Cornelia; Selitsch, Brigitte; Manafi, Mammad

    2001-01-01

    Candida ID agar allows identification of Candida albicans and differentiation of other Candida species. In comparison with CHROMagar Candida, we evaluated the performance of this medium directly from 596 clinical specimens. In particular, detection of C. albicans after 24 h of incubation was easier on Candida ID (sensitivity, 96.8%) than on CHROMagar (sensitivity, 49.6%). PMID:11574621

  16. 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.

  17. Description of Groenewaldozyma gen. nov. for placement of Candida auringiensis, Candida salmanticensis and Candida tartarivorans.

    PubMed

    Kurtzman, Cletus P

    2016-07-01

    DNA sequence analyses have demonstrated that species of the polyphyletic anamorphic ascomycete genus Candida may be members of described teleomorphic genera, members of the Candida tropicalis clade upon which the genus Candida is circumscribed, or members of isolated clades that represent undescribed genera. From phylogenetic analysis of gene sequences from nuclear large subunit rRNA, mitochondrial small subunit rRNA and cytochrome oxidase II, Candida auringiensis (NRRL Y-17674(T), CBS 6913(T)), Candida salmanticensis (NRRL Y-17090(T), CBS 5121(T)), and Candida tartarivorans (NRRL Y-27291(T), CBS 7955(T)) were shown to be members of an isolated clade and are proposed for reclassification in the genus Groenewaldozyma gen. nov. (MycoBank MB 815817). Neighbouring taxa include species of the Wickerhamiella clade and Candida blankii.

  18. Evolution and Application of Inteins in Candida species: A Review

    PubMed Central

    Fernandes, José A. L.; Prandini, Tâmara H. R.; Castro, Maria da Conceiçao A.; Arantes, Thales D.; Giacobino, Juliana; Bagagli, Eduardo; Theodoro, Raquel C.

    2016-01-01

    Inteins are invasive intervening sequences that perform an autocatalytic splicing from their host proteins. Among eukaryotes, these elements are present in many fungal species, including those considered opportunistic or primary pathogens, such as Candida spp. Here we reviewed and updated the list of Candida species containing inteins in the genes VMA, THRRS and GLT1 and pointed out the importance of these elements as molecular markers for molecular epidemiological researches and species-specific diagnosis, since the presence, as well as the size of these inteins, is polymorphic among the different species. Although absent in Candida albicans, these elements are present in different sizes, in some environmental Candida spp. and also in most of the non-albicans Candida spp. considered emergent opportunistic pathogens. Besides, the possible role of these inteins in yeast physiology was also discussed in the light of the recent findings on the importance of these elements as post-translational modulators of gene expression, reinforcing their relevance as alternative therapeutic targets for the treatment of non-albicans Candida infections, because, once the splicing of an intein is inhibited, its host protein, which is usually a housekeeping protein, becomes non-functional. PMID:27777569

  19. Candida Infection of the Bloodstream - Candidemia

    MedlinePlus

    Candida Infection of the Bloodstream– Candidemia Fungal Disease Series #4 Candida is the single most important cause of fungal infections worldwide. In the U.S., Candida is the 4th most common cause of bloodstream ...

  20. 21 CFR 173.165 - Candida lipolytica.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... Enzyme Preparations and Microorganisms § 173.165 Candida lipolytica. The food additive Candida lipolytica... following conditions: (a) The food additive is the enzyme system of the organism Candida lipolytica and...

  1. 21 CFR 173.165 - Candida lipolytica.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... Enzyme Preparations and Microorganisms § 173.165 Candida lipolytica. The food additive Candida lipolytica... following conditions: (a) The food additive is the enzyme system of the organism Candida lipolytica and...

  2. 21 CFR 173.165 - Candida lipolytica.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... Enzyme Preparations and Microorganisms § 173.165 Candida lipolytica. The food additive Candida lipolytica... following conditions: (a) The food additive is the enzyme system of the organism Candida lipolytica and...

  3. 21 CFR 173.165 - Candida lipolytica.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... Enzyme Preparations and Microorganisms § 173.165 Candida lipolytica. The food additive Candida lipolytica... following conditions: (a) The food additive is the enzyme system of the organism Candida lipolytica and...

  4. Candida species: new insights into biofilm formation.

    PubMed

    Cuéllar-Cruz, Mayra; López-Romero, Everardo; Villagómez-Castro, Julio C; Ruiz-Baca, Estela

    2012-06-01

    Biofilms of Candida albicans, Candida parapsilosis, Candida glabrata and Candida tropicalis are associated with high indices of hospital morbidity and mortality. Major factors involved in the formation and growth of Candida biofilms are the chemical composition of the medical implant and the cell wall adhesins responsible for mediating Candida-Candida, Candida-human host cell and Candida-medical device adhesion. Strategies for elucidating the mechanisms that regulate the formation of Candida biofilms combine tools from biology, chemistry, nanoscience, material science and physics. This review proposes the use of new technologies, such as synchrotron radiation, to study the mechanisms of biofilm formation. In the future, this information is expected to facilitate the design of new materials and antifungal compounds that can eradicate nosocomial Candida infections due to biofilm formation on medical implants. This will reduce dissemination of candidiasis and hopefully improve the quality of life of patients.

  5. Candida Parapsilosis and Candida Guillermondii: Emerging Pathogens in Nail Candidiasis

    PubMed Central

    Fich, Felix; Abarzúa-Araya, Alvaro; Pérez, Mario; Nauhm, Yalile; León, Eugenia

    2014-01-01

    Background: Onychomycosis of the fingernails and toenails is generally caused by dermatophytes and yeasts. Toenail mycoses involve mainly dermatophytes but when Candida is also involved, the strain most commonly isolated worldwide is C. albicans. Aims: To determine Candida strains prevailing in onychomycosis. Materials and Methods: A retrospective, observational and descriptive study of fungal cultures retrieved from the registry of the microbiology laboratory of the Pontificia Universidad Católica was performed. Specimens obtained from patients attending the healthcare network between December 2007 and December 2010 was analyzed. Statistical Analysis: A descriptive statistical analysis was performed. Results: Candida was retrieved from 467 of 8443 specimens (52% fingernails and 48% toenails). Cultures were negative in 5320 specimens (63.6%). Among Candida-positive cultures, parapsilosis was the most commonly isolated strain with 202 cases (43.3%). While isolates of Candida guillermondii were 113 (24.2%), those of Candida albicans were 110 (23.6%), those of spp. were 20 (4.3%) and there were 22 cases of other isolates (4.71%). Among the 467 patients with positive cultures for Candida, 136 (29,1%) were men and 331 (70,9%) were women. All patients were older than 18 years old. Clinical files were available for only 169 of the 467 patients with positive cultures for Candida. For those, age, gender, underlying illnesses and use of immunossupresive agents during the trial was reviewed. Conclusions: The present study shows that both C. parapsilosis as well as C. guillermondii appear as emerging pathogens that would be in fact taking the place of C. albicans as the most commonly isolated pathogen in patients with Candida onychomycosis. The relative percentage of C parapsilosis increases every year. Identification of Candida strains as etiological agents of nail candidiasis becomes relevant to the management both nail as well as systemic candidiasis, in view of the

  6. Echinocandin Resistance in Candida.

    PubMed

    Perlin, David S

    2015-12-01

    Invasive fungal infections are an important infection concern for patients with underlying immunosuppression. Antifungal therapy is a critical component of patient care, but therapeutic choices are limited due to few drug classes. Antifungal resistance, especially among Candida species, aggravates the problem. The echinocandin drugs (micafungin, anidulafungin, and caspofungin) are the preferred choice to treat a range of candidiasis. They target the fungal-specific enzyme glucan synthase, which is responsible for the biosynthesis of a major cell wall polymer. Therapeutic failure involves acquisition of resistance, although it is a rare event among most Candida species. However, in some settings, higher-level resistance has been reported among Candida glabrata, which is also frequently resistant to azole drugs, resulting in difficult-to-treat multidrug-resistant strains. The mechanism of echinocandin resistance involves amino acid changes in "hot spot" regions of FKS-encoded subunits of glucan synthase, which decreases the sensitivity of enzyme to drug, resulting in higher minimum inhibitory concentration values. The cellular processes promoting the formation of resistant FKS strains involve complex stress response pathways that yield a variety of adaptive compensatory genetic responses. Standardized broth microdilution techniques can be used to distinguish FKS mutant strains from wild type, but testing C. glabrata with caspofungin should be approached cautiously. Finally, clinical factors that promote echinocandin resistance include prophylaxis, host reservoirs including biofilms in the gastrointestinal tract, and intra-abdominal infections. An understanding of clinical and molecular factors that promote echinocandin resistance is critical to develop better diagnostic tools and therapeutic strategies to overcome resistance.

  7. Host response to Candida albicans bloodstream infection and sepsis

    PubMed Central

    Duggan, Seána; Leonhardt, Ines; Hünniger, Kerstin; Kurzai, Oliver

    2015-01-01

    Candida albicans is a major cause of bloodstream infection which may present as sepsis and septic shock - major causes of morbidity and mortality world-wide. After invasion of the pathogen, innate mechanisms govern the early response. Here, we outline the models used to study these mechanisms and summarize our current understanding of innate immune responses during Candida bloodstream infection. This includes protective immunity as well as harmful responses resulting in Candida induced sepsis. Neutrophilic granulocytes are considered principal effector cells conferring protection and recognize C. albicans mainly via complement receptor 3. They possess a range of effector mechanisms, contributing to elimination of the pathogen. Neutrophil activation is closely linked to complement and modulated by activated mononuclear cells. A thorough understanding of these mechanisms will help in creating an individualized approach to patients suffering from systemic candidiasis and aid in optimizing clinical management. PMID:25785541

  8. The disulfide oxidoreductase SdbA is active in Streptococcus gordonii using a single C-terminal cysteine of the CXXC motif.

    PubMed

    Davey, Lauren; Cohen, Alejandro; LeBlanc, Jason; Halperin, Scott A; Lee, Song F

    2016-01-01

    Recently, we identified a novel disulfide oxidoreductase, SdbA, in the oral bacterium Streptococcus gordonii. Disulfide oxidoreductases form disulfide bonds in nascent proteins using a CXXC catalytic motif. Typically, the N-terminal cysteine interacts with substrates, whereas the C-terminal cysteine is buried and only reacts with the first cysteine of the motif. In this study, we investigated the SdbA C(86) P(87) D(88) C(89) catalytic motif. In vitro, SdbA single cysteine variants at the N or C-terminal position (SdbAC86P and SdbAC89A ) were active but displayed different susceptibility to oxidation, and N-terminal cysteine was prone to sulfenylation. In S. gordonii, mutants with a single N-terminal cysteine were inactive and formed unstable disulfide adducts with other proteins. Activity was partially restored by inactivation of pyruvate oxidase, a hydrogen peroxide generator. Presence of the C-terminal cysteine alone (in the SdbAC86P variant) could complement the ΔsdbA mutant and restore disulfide bond formation in recombinant and natural protein substrates. These results provide evidence that certain disulfide oxidoreductases can catalyze disulfide bond formation using a single cysteine of the CXXC motif, including the buried C-terminal cysteine.

  9. Determination of the appetite suppressant P57 in Hoodia gordonii plant extracts and dietary supplements by liquid chromatography/electrospray ionization mass spectrometry (LC-MSD-TOF) and LC-UV methods.

    PubMed

    Avula, Bharathi; Wang, Yan-Hong; Pawar, Rahul S; Shukla, Yatin J; Schaneberg, Brian; Khan, Ikhlas A

    2006-01-01

    Hoodia gordonii is traditionally used in South Africa for its appetite suppressant properties. P57AS3 (P57), an oxypregnane steroidal glycoside, is the only reported active constituent from this plant as an appetite suppressant. Effective quality control of these extracts or products requires rapid methods to determine P57 content. New methods of liquid chromatography/mass spectrometry (LC/MS) and LC-UV for analysis of P57 from H. gordonii have been developed. The quantitative determination of P57 was achieved with a Phenomenex Gemini (Torrance, CA) reversed-phase column using gradient mobile phase of water and acetonitrile, both containing 0.1% acetic acid. The method was validated for linearity, repeatability, and limits of detection and quantification. Good results were obtained in terms of repeatability (relative standard deviation <5.0%) and recovery (98.5-103.5%). The developed methods were applied to the determination of P57 for H. gordonii plant samples, one related genus (Opuntia ficus-indica), and dietary supplements that claim to contain H. gordonii.

  10. Candida albicans Secreted Aspartyl Proteinases in Virulence and Pathogenesis

    PubMed Central

    Naglik, Julian R.; Challacombe, Stephen J.; Hube, Bernhard

    2003-01-01

    Candida albicans is the most common fungal pathogen of humans and has developed an extensive repertoire of putative virulence mechanisms that allows successful colonization and infection of the host under suitable predisposing conditions. Extracellular proteolytic activity plays a central role in Candida pathogenicity and is produced by a family of 10 secreted aspartyl proteinases (Sap proteins). Although the consequences of proteinase secretion during human infections is not precisely known, in vitro, animal, and human studies have implicated the proteinases in C. albicans virulence in one of the following seven ways: (i) correlation between Sap production in vitro and Candida virulence, (ii) degradation of human proteins and structural analysis in determining Sap substrate specificity, (iii) association of Sap production with other virulence processes of C. albicans, (iv) Sap protein production and Sap immune responses in animal and human infections, (v) SAP gene expression during Candida infections, (vi) modulation of C. albicans virulence by aspartyl proteinase inhibitors, and (vii) the use of SAP-disrupted mutants to analyze C. albicans virulence. Sap proteins fulfill a number of specialized functions during the infective process, which include the simple role of digesting molecules for nutrient acquisition, digesting or distorting host cell membranes to facilitate adhesion and tissue invasion, and digesting cells and molecules of the host immune system to avoid or resist antimicrobial attack by the host. We have critically discussed the data relevant to each of these seven criteria, with specific emphasis on how this proteinase family could contribute to Candida virulence and pathogenesis. PMID:12966142

  11. Antimicrobial Decapeptide KSL-W Attenuates Candida albicans Virulence by Modulating Its Effects on Toll-Like Receptor, Human Beta-Defensin, and Cytokine Expression by Engineered human Oral Mucosa

    DTIC Science & Technology

    2011-02-02

    University, Quebec, QC, Canada b Microbiology Branch, US Army Dental and Trauma Research Detachment, Institute of Surgical Research, Fort Sam Houston, TX, USA...innate immunity of epithelial cells in prevent - ing Candida infection of the oral mucosa. Primary epithelial cells obtained from various sources...play a role in preventing microbial infections [8,19,45]. Generally, these antimicrobial peptides exhibit selective toxicity for microorganisms and

  12. Candida albicans pathogenicity mechanisms

    PubMed Central

    Mayer, François L.; Wilson, Duncan; Hube, Bernhard

    2013-01-01

    The polymorphic fungus Candida albicans is a member of the normal human microbiome. In most individuals, C. albicans resides as a lifelong, harmless commensal. Under certain circumstances, however, C. albicans can cause infections that range from superficial infections of the skin to life-threatening systemic infections. Several factors and activities have been identified which contribute to the pathogenic potential of this fungus. Among them are molecules which mediate adhesion to and invasion into host cells, the secretion of hydrolases, the yeast-to-hypha transition, contact sensing and thigmotropism, biofilm formation, phenotypic switching and a range of fitness attributes. Our understanding of when and how these mechanisms and factors contribute to infection has significantly increased during the last years. In addition, novel virulence mechanisms have recently been discovered. In this review we present an update on our current understanding of the pathogenicity mechanisms of this important human pathogen. PMID:23302789

  13. Thrush and Other Candida Infections

    MedlinePlus

    ... diagnosis by examining your child and her symptoms. Scrapings of Candida lesions inside the mouth or elsewhere ... Academy of Pediatrics) The information contained on this Web site should not be used as a substitute ...

  14. Antimicrobial GL13K Peptide Coatings Killed and Ruptured the Wall of Streptococcus gordonii and Prevented Formation and Growth of Biofilms

    PubMed Central

    Chen, Xi; Hirt, Helmut; Li, Yuping; Gorr, Sven-Ulrik; Aparicio, Conrado

    2014-01-01

    Infection is one of the most prevalent causes for dental implant failure. We have developed a novel antimicrobial peptide coating on titanium by immobilizing the antimicrobial peptide GL13K. GL13K was developed from the human salivary protein BPIFA2. The peptide exhibited MIC of 8 µg/ml against planktonic Pseudonomas aeruginosa and their biofilms were reduced by three orders of magnitude with 100 µg/ml GL13K. This peptide concentration also killed 100% of Streptococcus gordonii. At 1 mg/ml, GL13K caused less than 10% lysis of human red blood cells, suggesting low toxicity to mammalian cells. Our GL13K coating has also previously showed bactericidal effect and inhibition of biofilm growth against peri-implantitis related pathogens, such as Porphyromonas gingivalis. The GL13K coating was cytocompatible with human fibroblasts and osteoblasts. However, the bioactivity of antimicrobial coatings has been commonly tested under (quasi)static culture conditions that are far from simulating conditions for biofilm formation and growth in the oral cavity. Oral salivary flow over a coating is persistent, applies continuous shear forces, and supplies sustained nutrition to bacteria. This accelerates bacteria metabolism and biofilm growth. In this work, the antimicrobial effect of the coating was tested against Streptococcus gordonii, a primary colonizer that provides attachment for the biofilm accretion by P. gingivalis, using a drip-flow biofilm bioreactor with media flow rates simulating salivary flow. The GL13K peptide coatings killed bacteria and prevented formation and growth of S. gordonii biofilms in the drip-flow bioreactor and under regular mild-agitation conditions. Surprisingly the interaction of the bacteria with the GL13K peptide coatings ruptured the cell wall at their septum or polar areas leaving empty shell-like structures or exposed protoplasts. The cell wall rupture was not detected under regular culture conditions, suggesting that cell wall rupture induced

  15. Role of gallium and silver from phosphate-based glasses on in vitro dual species oral biofilm models of Porphyromonas gingivalis and Streptococcus gordonii.

    PubMed

    Valappil, Sabeel P; Coombes, Marc; Wright, Lucy; Owens, Gareth J; Lynch, Richard J M; Hope, Christopher K; Higham, Susan M

    2012-05-01

    Phosphate-based glasses (PBGs) are excellent controlled delivery agents for antibacterial ions such as silver and gallium. The aim of this study was to assess the potential utility of novel PBGs combining both gallium and silver for use in periodontal therapy. To this end, an in vitro biofilm model with the putative periodontal pathogen, Porphyromonas gingivalis, and an initial colonizer, Streptococcus gordonii, was established. The effect of increasing calcium content in gallium-silver-doped PBG on the susceptibility of P. gingivalis was examined. A decrease in degradation rates (30.34, 25.19, 21.40 μg mm(-2) h(-1)) with increasing PBG calciumcontent (10, 11, 12 mol.% respectively) was observed, correlating well with gallium and silver ion release and antimicrobial activity against planktonic P. gingivalis (approximately 5.4log(10) colony-forming units (CFU) reduction after 24h by the C10 glass compared with controls) and S. gordonii (total growth inhibition after 32h by C10, C11 and C12 glasses compared with controls). The most potent PBG (C10) was evaluated for its ability to inhibit the biofilm growth of P. gingivalis in a newly established constant-depth film fermentor model. The simultaneous release of silver and gallium from the glass reduced P. gingivalis biofilm growth with a maximum effect (1.92log(10) CFU reduction) after 168 h. Given the emergence of antibiotic-resistant bacteria and dearth of new antibiotics in development, the glasses, especially C10, would offer effective alternatives to antibiotics or may complement current therapies through controlled, localized delivery of gallium and silver ions at infected sites in the oral cavity.

  16. Supplementation of CHROMagar Candida medium with Pal's medium for rapid identification of Candida dubliniensis.

    PubMed

    Sahand, Ismail H; Moragues, María D; Eraso, Elena; Villar-Vidal, María; Quindós, Guillermo; Pontón, José

    2005-11-01

    CHROMagar Candida medium is used for the isolation and identification of Candida species, but it does not differentiate Candida albicans from Candida dubliniensis. This differentiation can be achieved by using Pal's agar, which cannot be used in primary isolation. We have combined both media to obtain a new medium that can be used for the isolation and identification of C. dubliniensis in primary cultures.

  17. Candida famata (Debaryomyces hansenii)

    NASA Astrophysics Data System (ADS)

    Sibirny, Andriy A.; Voronovsky, Andriy Y.

    Debaryomyces hansenii (teleomorph of asporogenous strains known as Candida famata ) belongs to the group of so named ‘ flavinogenic yeasts ’ capable of riboflavin oversynthesis during starvation for iron. Some strains of C. famata belong to the most flavinogenic organisms known (accumulate 20 mg of riboflavin in 1 ml of the medium) and were used for industrial production of riboflavin in USA for long time. Many strains of D. hansenii are characterized by high salt tolerance and are used for ageing of cheeses whereas some others are able to convert xylose to xylitol, anti-caries sweetener. Transformation system has been developed for D. hansenii. It includes collection of host recipient strains, vectors with complementation and dominant markers and several transformation protocols based on protoplasting and electroporation. Besides, methods of multicopy gene insertion and insertional mutagenesis have been developed and several strong constitutive and regulatable promoters have been cloned. All structural genes of riboflavin synthesis and some regulatory genes involved in this process have been identified. Genome of D. hansenii has been sequenced in the frame of French National program ‘Genolevure’ and is opened for public access

  18. 21 CFR 173.160 - Candida guilliermondii.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... CONSUMPTION Enzyme Preparations and Microorganisms § 173.160 Candida guilliermondii. The food additive Candida... the following conditions: (a) The food additive is the enzyme system of the viable organism...

  19. 21 CFR 173.160 - Candida guilliermondii.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... CONSUMPTION Enzyme Preparations and Microorganisms § 173.160 Candida guilliermondii. The food additive Candida... the following conditions: (a) The food additive is the enzyme system of the viable organism...

  20. 21 CFR 173.160 - Candida guilliermondii.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... CONSUMPTION Enzyme Preparations and Microorganisms § 173.160 Candida guilliermondii. The food additive Candida... the following conditions: (a) The food additive is the enzyme system of the viable organism...

  1. Isolation of Candida Protoplasts from a Case of Candida Endocarditis

    PubMed Central

    Rosner, Richard

    1966-01-01

    Rosner, Richard (St. Joseph's Hospital, Paterson, N.J.). Isolation of Candida protoplasts from a case of Candida endocarditis. J. Bacteriol. 91:1320–1326. 1966.—A case of endocarditis caused by Candida tropicalis is described. Even though the patient was receiving adequate therapy, and all routine blood cultures were negative for growth, the patient continued to give clinical evidence of active, progressive endocarditis. The isolation of osmotically fragile bodies from blood cultures placed in an osmotically controlled medium is described in detail. The role of these bodies, called protoplasts, in the active disease process of this patient is discussed in relation to the criteria for the implication of protoplasts in the disease process. Several explanations as to what caused the in vivo formation of protoplasts of C. tropicalis in this patient are discussed. Images PMID:4160231

  2. Antifungal activity against Candida biofilms.

    PubMed

    Iñigo, Melania; Pemán, Javier; Del Pozo, Jose L

    2012-10-01

    Candida species have two distinct lifestyles: planktonic, and surface-attached communities called biofilms. Mature C. albicans biofilms show a complex three-dimensional architecture with extensive spatial heterogeneity, and consist of a dense network of yeast, hyphae, and pseudohyphae encased within a matrix of exopolymeric material. Several key processes are likely to play vital roles at the different stages of biofilm development, such as cell-substrate and cell-cell adherence, hyphal development, and quorum sensing. Biofilm formation is a survival strategy, since biofilm yeasts are more resistant to antifungals and environmental stress. Antifungal resistance is a multifactorial process that includes multidrug efflux pumps, target proteins of the ergosterol biosynthetic pathway. Most studies agree in presenting azoles as agents with poor activity against Candida spp. biofilms. However, recent studies have demonstrated that echinocandins and amphotericin B exhibit remarkable activity against C. albicans and Candida non-albicans biofilms. The association of Candida species with biofilm formation increases the therapeutic complexity of foreign body-related yeast infections. The traditional approach to the management of these infections has been to explant the affected device. There is a strong medical but also economical motivation for the development of novel anti-fungal biofilm strategies due to the constantly increasing resistance of Candida biofilms to conventional antifungals, and the high mortality caused by related infections. A better description of the extent and role of yeast in biofilms may be critical for developing novel therapeutic strategies in the clinical setting.

  3. [Candida biofilm-related infections].

    PubMed

    Del Pozo, José Luis; Cantón, Emilia

    2016-01-01

    The number of biomedical devices (intravascular catheters, heart valves, joint replacements, etc.) that are implanted in our hospitals has increased exponentially in recent years. Candida species are pathogens which are becoming more significant in these kinds of infections. Candida has two forms of development: planktonic and in biofilms. A biofilm is a community of microorganisms which adhere to a surface and are enclosed by an extracellular matrix. This form of development confers a high resistance to the antimicrobial agents. This is the reason why antibiotic treatments usually fail and biomedical devices may have to be removed in most cases. Unspecific adhesion mechanisms, the adhesion-receptor systems, and an intercellular communication system called quorum sensing play an essential role in the development of Candida biofilms. In general, the azoles have poor activity against Candida biofilms, while echinocandins and polyenes show a greater activity. New therapeutic strategies need to be developed due to the high morbidity and mortality and high economic costs associated with these infections. Most studies to date have focused on bacterial biofilms. The knowledge of the formation of Candida biofilms and their composition is essential to develop new preventive and therapeutic strategies.

  4. Usefulness of Candida ID2 agar for the presumptive identification of Candida dubliniensis.

    PubMed

    Eraso, Elena; Sahand, Ismail H; Villar-Vidal, María; Marcos, Cristina; Dolores Moragues, María; Madariaga, Lucila; Pontón, José; Quindós, Guillermo

    2006-11-01

    CHROMagar Candida and Candida ID2 are widely used for the isolation and presumptive identification of Candida spp. based on the color of the colonies on these two media. We have studied the usefulness of these chromogenic media for differentiating Candida dubliniensis from Candida albicans isolates. One hundred isolates of C. dubliniensis and 100 C. albicans isolates were tested on Candida ID2, CHROMagar Candida (CHROMagar), and CHROMagar Candida reformulated by BBL. CHROMagar Candida and CHROMagar Candida BBL did not allow a clear differentiation of the two species based upon the shade of the green color of C. dubliniensis colonies. However, on Candida ID2, all C. dubliniensis isolates produced turquoise blue colonies whereas 91% of C. albicans colonies were cobalt blue. The sensitivity and the specificity for differentiating between C. dubliniensis fromC. albicans on Candida ID2 were 100% and 91%, respectively; whereas on CHROMagar Candida these values were 63% and 89% and on CHROMagar Candida BBL they were 18% and 98%. Candida ID2 agar provides a simple and accurate laboratory approach for the identification and differentiation of C. dubliniensis on the basis of the colony color.

  5. Metal resistance in Candida biofilms.

    PubMed

    Harrison, Joe J; Rabiei, Maryam; Turner, Raymond J; Badry, Erin A; Sproule, Kimberley M; Ceri, Howard

    2006-03-01

    Yeasts are often successful in metal-polluted environments; therefore, the ability of biofilm and planktonic cell Candida tropicalis to endure metal toxicity was investigated. Fifteen water-soluble metal ions, chosen to represent groups 6A to 6B of the periodic table, were tested against this organism. With in vitro exposures as long as 24 h, biofilms were up to 65 times more tolerant to killing by metals than corresponding planktonic cultures. Of the most toxic heavy metals tested, only very high concentrations of Hg2+, CrO4 (2-) or Cu2+ killed surface-adherent Candida. Metal-chelator precipitates could be formed in biofilms following exposure to the heavy metals Cu2+ and Ni2+. This suggests that Candida biofilms may adsorb metal cations from their surroundings and that sequestration in the extracellular matrix may contribute to resistance. We concluded that biofilm formation may be a strategy for metal resistance and/or tolerance in yeasts.

  6. Pancreatic infection with Candida parapsilosis.

    PubMed

    Ibáñez, R; Serrano-Heranz, R

    1999-01-01

    Candida species other than C. albicans have been implicated as pathogens in intravascular (bloodstream, intravascular devices, endocarditis) and extravascular (arthritis, osteomielitis, endophtalmitis) infections. C. parapsilosis, however, is rarely implicated in intra-abdominal infections (peritonitis during peritoneal dialysis, complicating surgery or solid-organ transplantation). We describe a case of a 48-y-old male with acute pancreatitis who had a pancreatic abscess produced by primary C. parapsilosis infection. Although he received adequate treatment with antifungal medication and surgical drainage, the outcome was fatal. Because the clinical findings are indistinguishable from bacterial abscesses, Candida species should be considered in cases of complicated pancreatitis, in order to establish a prompt adequate treatment.

  7. Genotyping Candida albicans from Candida leukoplakia and non-Candida leukoplakia shows no enrichment of multilocus sequence typing clades but enrichment of ABC genotype C in Candida leukoplakia.

    PubMed

    Abdulrahim, Mohammed H; McManus, Brenda A; Flint, Stephen R; Coleman, David C

    2013-01-01

    Oral leukoplakias are histopathologically-diagnosed as Candida leukoplakia or non-Candida leukoplakia by the presence or absence of hyphae in the superficial epithelium. Candida leukoplakia lesions have significantly increased malignant potential. Candida albicans is the most prevalent fungal species associated with oral leukoplakia and may contribute to malignant transformation of Candida leukoplakia. To date, no detailed population analysis of C. albicans isolates from oral leukoplakia patients has been undertaken. This study investigated whether specific C. albicans genotypes were associated with Candida leukoplakia and non-Candida leukoplakia in a cohort of Irish patients. Patients with histopathologically-defined Candida leukoplakia (n = 31) or non-Candida leukoplakia (n = 47) were screened for Candida species by culture of oral rinse and lesional swab samples. Selected C. albicans isolates from Candida leukoplakia patients (n = 25), non-Candida leukoplakia patients (n = 19) and oral carriage isolates from age and sex matched healthy subjects without leukoplakia (n = 34) were subjected to multilocus sequence typing (MLST) and ABC genotyping. MLST revealed that the clade distribution of C. albicans from both Candida leukoplakia and non-Candida leukoplakia lesions overlapped with the corresponding clade distributions of oral carriage isolates and global reference isolates from the MLST database indicating no enrichment of leukoplakia-associated clones. Oral leukoplakia isolates were significantly enriched with ABC genotype C (12/44, 27.3%), particularly Candida leukoplakia isolates (9/25, 36%), relative to oral carriage isolates (3/34, 8.8%). Genotype C oral leukoplakia isolates were distributed in MLST clades 1,3,4,5,8,9 and 15, whereas genotype C oral carriage isolates were distributed in MLST clades 4 and 11.

  8. Expansion of the Candida tanzawaensis yeast clade: 16 novel Candida species from basidiocarp-feeding beetles.

    PubMed

    Suh, Sung-Oui; McHugh, Joseph V; Blackwell, Meredith

    2004-11-01

    A major clade of new yeast taxa from the digestive tract of basidiocarp-feeding beetles is recognized based on rRNA gene sequence analyses. Almost 30 % of 650 gut isolates formed a statistically well-supported clade that included Candida tanzawaensis. The yeasts in the clade were isolated from 11 families of beetles, of which Tenebrionidae and Erotylidae were most commonly sampled. Repeated isolation of certain yeasts from the same beetle species at different times and places indicated strong host associations. Sexual reproduction was never observed in the yeasts. Based on comparisons of small- and large-subunit rRNA gene sequences and morphological and physiological traits, the yeasts were placed in Candida ambrosiae and in 16 other undescribed taxa. In this report, the novel species in the genus Candida are described and their relationships with other taxa in the Saccharomycetes are discussed. The novel species and their type strains are as follows: Candida guaymorum (NRRL Y-27568(T)=CBS 9823(T)), Candida bokatorum (NRRL Y-27571(T)=CBS 9824(T)), Candida kunorum (NRRL Y-27580(T)=CBS 9825(T)), Candida terraborum (NRRL Y-27573(T)=CBS 9826(T)), Candida emberorum (NRRL Y-27606(T)=CBS 9827(T)), Candida wounanorum (NRRL Y-27574(T)=CBS 9828(T)), Candida yuchorum (NRRL Y-27569(T)=CBS 9829(T)), Candida chickasaworum (NRRL Y-27566(T)=CBS 9830(T)), Candida choctaworum (NRRL Y-27584(T)=CBS 9831(T)), Candida bolitotheri (NRRL Y-27587(T)=CBS 9832(T)), Candida atakaporum (NRRL Y-27570(T)=CBS 9833(T)), Candida panamericana (NRRL Y-27567(T)=CBS 9834(T)), Candida bribrorum (NRRL Y-27572(T)=CBS 9835(T)), Candida maxii (NRRL Y-27588(T)=CBS 9836(T)), Candida anneliseae (NRRL Y-27563(T)=CBS 9837(T)) and Candida taliae (NRRL Y-27589(T)=CBS 9838(T)).

  9. 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.

  10. Biofilm lifestyle of Candida: a mini review.

    PubMed

    Seneviratne, C J; Jin, L; Samaranayake, L P

    2008-10-01

    Candida is the major fungal pathogen of humans causing a variety of afflictions ranging from superficial mucosal diseases to deep seated mycoses. Biofilm formation is a major virulence factor in the pathogenicity of Candida, and Candida biofilms are difficult to eradicate especially because of their very high antifungal resistance. Consequently, research into the pathogenicity of Candida has focused on the prevention and management of biofilm development, their architecture, and antifungal resistance. Although studies have shed some light, molecular mechanisms that govern biofilm formation and pathogenicity still await full clarification. This review outlines the key features of what is currently known of Candida biofilm development, regulation and antifungal resistance and, their proteomics.

  11. Synthetic arylquinuclidine derivatives exhibit antifungal activity against Candida albicans, Candida tropicalis and Candida parapsilopsis

    PubMed Central

    2011-01-01

    Background 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. Methods 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. Results 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. Conclusion Taken together, our data demonstrate that arylquinuclidine derivatives could be useful as lead compounds for the rational synthesis of new antifungal drugs. PMID

  12. Candida species from oral cavity of HIV-infected children exhibit reduced virulence factors in the HAART era.

    PubMed

    Portela, Maristela Barbosa; Lima de Amorim, Elaine; Santos, Adrielle Mangabeira; Alexandre da Rocha Curvelo, José; de Oliveira Martins, Karol; Capillé, Cauli Lima; Maria de Araújo Soares, Rosangela; Barbosa de Araújo Castro, Gloria Fernanda

    2017-01-01

    This study aimed to assess, in vitro, the biofilm viability and the phospholipase and protease production of Candida spp. from the saliva of HIV infected children and healthy controls, and to correlate the results with the use of medical data. A total of 79 isolates were analyzed: 48 Candida albicans isolates (33/15) and 20 Candida parapsilosis sensu lato complex isolates (12/8) (from HIV/control patients, respectively), and 8 Candida krusei, 1 Candida tropicalis, 1 Candida dubliniensis and 1 Candida guilliermondii from HIV patients. The XTT (2, 3-bis (2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-Carboxanilide) reduction assay analyzed the biofilm viability. Phospholipase and protease assays were performed using the egg yolk and Bovine Serum Albumin agar plate methods, respectively. All isolates were able to form biofilm with cell viability. Quantitatively, Candida isolates from both groups presented a similar ability to form biofilm (p > 0.05). The biofilm viability activity was higher in C. albicans isolates than in non-albicans Candida isolates (p < 0.05) for both groups. Phospholipase activity was detected in 32 isolates (40.5%) and it was significantly higher in the HIV group (p = 0.006). Protease activity was detected in 66 isolates (84.8%) and most of them were relatively/very strong producers. No statistical association with medical data was found in the HIV group. Although Candida spp. isolates from HIV-positive children presented higher phospholipase production, in vitro they exhibited reduced virulence factors compared to isolates from healthy individuals. This finding may enlighten the role played by immunosuppression in the modulation of Candida virulence attributes.

  13. Urinary tract infections and Candida albicans

    PubMed Central

    Behzadi, Payam; Behzadi, Elham

    2015-01-01

    Introduction Urinary tract candidiasis is known as the most frequent nosocomial fungal infection worldwide. Candida albicans is the most common cause of nosocomial fungal urinary tract infections; however, a rapid change in the distribution of Candida species is undergoing. Simultaneously, the increase of urinary tract candidiasis has led to the appearance of antifungal resistant Candida species. In this review, we have an in depth look into Candida albicans uropathogenesis and distribution of the three most frequent Candida species contributing to urinary tract candidiasis in different countries around the world. Material and methods For writing this review, Google Scholar –a scholarly search engine– (http://scholar.google.com/) and PubMed database (http://www.ncbi.nlm.nih.gov/pubmed/) were used. The most recently published original articles and reviews of literature relating to the first three Candida species causing urinary tract infections in different countries and the pathogenicity of Candida albicans were selected and studied. Results Although some studies show rapid changes in the uropathogenesis of Candida species causing urinary tract infections in some countries, Candida albicans is still the most important cause of candidal urinary tract infections. Conclusions Despite the ranking of Candida albicans as the dominant species for urinary tract candidiasis, specific changes have occurred in some countries. At this time, it is important to continue the surveillance related to Candida species causing urinary tract infections to prevent, control and treat urinary tract candidiasis in future. PMID:25914847

  14. Candida parapsilosis Protects Premature Intestinal Epithelial Cells from Invasion and Damage by Candida albicans

    PubMed Central

    Gonia, Sara; Archambault, Linda; Shevik, Margaret; Altendahl, Marie; Fellows, Emily; Bliss, Joseph M.; Wheeler, Robert T.; Gale, Cheryl A.

    2017-01-01

    Candida is a leading cause of late-onset sepsis in premature infants and is thought to invade the host via immature or damaged epithelial barriers. We previously showed that the hyphal form of Candida albicans invades and causes damage to premature intestinal epithelial cells (pIECs), whereas the non-hyphal Candida parapsilosis, also a fungal pathogen of neonates, has less invasion and damage abilities. In this study, we investigated the potential for C. parapsilosis to modulate pathogenic interactions of C. albicans with the premature intestine. While a mixed infection with two fungal pathogens may be expected to result in additive or synergistic damage to pIECs, we instead found that C. parapsilosis was able to protect pIECs from invasion and damage by C. albicans. C. albicans-induced pIEC damage was reduced to a similar extent by multiple different C. parapsilosis strains, but strains differed in their ability to inhibit C. albicans invasion of pIECs, with the inhibitory activity correlating with their adhesiveness for C. albicans and epithelial cells. C. parapsilosis cell-free culture fractions were also able to significantly reduce C. albicans adhesion and damage to pIECs. Furthermore, coadministration of C. parapsilosis cell-free fractions with C. albicans was associated with decreased infection and mortality in zebrafish. These results indicate that C. parapsilosis is able to reduce invasion, damage, and virulence functions of C. albicans. Additionally, the results with cellular and cell-free fractions of yeast cultures suggest that inhibition of pathogenic interactions between C. albicans and host cells by C. parapsilosis occurs via secreted molecules as well as by physical contact with the C. parapsilosis cell surface. We propose that non-invasive commensals can be used to inhibit virulence features of pathogens and deserve further study as a non-pharmacological strategy to protect the fragile epithelial barriers of premature infants. PMID:28382297

  15. New spirorotenoids from Tephrosia candida.

    PubMed

    Andrei, Cesar C; Vieira, Paulo C; Fernandes, João B; da Silva, M Fátima das G F; Rodrigues Fo, Edson

    2002-01-01

    The ethyl acetate extract of roots of Tephrosia candida afforded three new spirorotenoids belonging to a new class of spirocompounds, named tephrospirolactone, tephrospiroketone I, and tephrospiroketone II. The structures of these compounds were determined mainly based on spectral analysis. The only known spirorotenoid described in the literature is amorphispironone, isolated from Amorpha fruticosa.

  16. Candida urinary tract infection: pathogenesis.

    PubMed

    Fisher, John F; Kavanagh, Kevin; Sobel, Jack D; Kauffman, Carol A; Newman, Cheryl A

    2011-05-01

    Candida species are unusual causes of urinary tract infection (UTI) in healthy individuals, but common in the hospital setting or among patients with predisposing diseases and structural abnormalities of the kidney and collecting system. The urinary tract may be invaded in either an antegrade fashion from the bloodstream or retrograde via the urethra and bladder. Candida species employ a repertoire of virulence factors, including phenotypic switching, dimorphism, galvano - and thigmotropism, and hydrolytic enzymes, to colonize and then invade the urinary tract. Antegrade infection occurs primarily among patients predisposed to candidemia. The process of adherence to and invasion of the glomerulus, renal blood vessels, and renal tubules by Candida species was elegantly described in early histopathologic studies. Armed with modern molecular biologic techniques, the various virulence factors involved in bloodborne infection of the kidney are gradually being elucidated. Disturbances of urine flow, whether congenital or acquired, instrumentation of the urinary tract, diabetes mellitus, antimicrobial therapy, and immunosuppression underlie most instances of retrograde Candida UTI. In addition, bacterial UTIs caused by Enterobacteriaceae may facilitate the initial step in the process. Ascending infections generally do not result in candidemia in the absence of obstruction.

  17. Candida albicans: adapting to succeed.

    PubMed

    Kadosh, David; Lopez-Ribot, Jose L

    2013-11-13

    In this issue of Cell Host & Microbe, Lu et al. (2013) report on the redundancy of signaling pathways controlling Candida albicans filamentation and pathogenicity. In the process, they provide important insight into how this normal commensal of humans adapts to different host microenvironments to become a highly successful opportunistic pathogen.

  18. Candida osteomyelitis in a gelding

    PubMed Central

    Doyle, Aimie; López, Alfonso; Pack, LeeAnn; Muckle, Anne

    2013-01-01

    A 2-year-old gelding was referred for evaluation of severe right forelimb lameness. The horse was grade 4/5 lame on the right forelimb. Clinical, laboratory, and radiographic findings were consistent with septic arthritis and osteomyelitis. Due to poor prognosis the owner elected euthanasia. Histopathology confirmed chronic arthritis and osteomyelitis with intralesional yeast (Candida species). PMID:23904643

  19. Amylase-binding proteins A (AbpA) and B (AbpB) differentially affect colonization of rats' teeth by Streptococcus gordonii.

    PubMed

    Tanzer, J M; Grant, L; Thompson, A; Li, L; Rogers, J D; Haase, E M; Scannapieco, F A

    2003-09-01

    Streptococcus gordonii produces two alpha-amylase-binding proteins, AbpA and AbpB, that have been extensively studied in vitro. Little is known, however, about their significance in oral colonization and cariogenicity (virulence). To clarify these issues, weanling specific pathogen-free Osborne-Mendel rats, TAN : SPFOM(OM)BR, were inoculated either with wild-type strains FAS4-S or Challis-S or with strains having isogenic mutations of abpA, abpB, or both, to compare their colonization abilities and persistence on the teeth. Experiments were done with rats fed a sucrose-rich diet containing low amounts of starch or containing only starch. The mutants and wild-types were quantified in vivo and carious lesions were scored. In 11 experiments, S. gordonii was a prolific colonizer of the teeth when rats were fed the sucrose (with low starch)-supplemented diet, often dominating the flora. Sucrose-fed rats had several-fold higher recoveries of inoculants than those eating the sucrose-free, starch-supplemented diet, regardless of inoculant type. The strain defective in AbpB could not colonize teeth of starch-only-eating rats, but could colonize rats if sucrose was added to the diet. Strains defective in AbpA surprisingly colonized better than their wild-types. A double mutant deficient in both AbpA and AbpB (abpA/abpB) colonized like its wild-type. Wild-types FAS4-S and Challis-S had no more than marginal cariogenicity. Notably, in the absence of AbpA, cariogenicity was slightly augmented. Both the rescue of colonization by the AbpB- mutant and the augmentation of colonization by AbpA- mutant in the presence of dietary sucrose suggested additional amylase-binding protein interactions relevant to colonization. Glucosyltransferase activity was greater in mutants defective in abpA and modestly increased in the abpB mutant. It was concluded that AbpB is required for colonization of teeth of starch-eating rats and its deletion is partially masked if rats eat a sucrose

  20. Calcineurin signaling: lessons from Candida species.

    PubMed

    Yu, Shang-Jie; Chang, Ya-Lin; Chen, Ying-Lien

    2015-06-01

    Human fungal infections have significantly increased in recent years due to the emergence of immunocompromised patients with AIDS and cancer. Among them, Candida species are frequently isolated and associated with high mortality if not appropriately treated. Current antifungal drugs (azoles, echinocandins and polyenes) are not sufficient to combat Candida species particularly those that are drug resistant. Calcineurin, a calcium/calmodulin-dependent protein phosphatase, is an attractive antifungal drug target, and its inhibitor (FK506 or cyclosporin A) can be combined with azoles or echinocandins for use against multidrug-resistant Candida species. The role of calcineurin in the hyphal growth of Candida albicans is controversial, but its roles in C. dubliniensis, C. tropicalis and C. lusitaniae can be demonstrated. In addition, calcineurin is required for virulence of Candida species in murine systemic, ocular or urinary infection models. However, the requirement for calcineurin substrate Crz1 in these infection models varies in Candida species, suggesting that Crz1 has diverse functions in different Candida species. Besides being critical for growth in serum of Candida species, calcineurin is critical for plasma membrane integrity and growth at body temperature (37°C) uniquely in C. glabrata, suggesting that Candida calcineurin controls pathogenesis via various novel mechanisms. In this review, we summarize studies of calcineurin signaling and hyphal growth, virulence and its relationship with drug tolerance in Candida species, focusing on the divergent and conserved functions.

  1. Supplementation of CHROMagar Candida Medium with Pal's Medium for Rapid Identification of Candida dubliniensis

    PubMed Central

    Sahand, Ismail H.; Moragues, María D.; Eraso, Elena; Villar-Vidal, María; Quindós, Guillermo; Pontón, José

    2005-01-01

    CHROMagar Candida medium is used for the isolation and identification of Candida species, but it does not differentiate Candida albicans from Candida dubliniensis. This differentiation can be achieved by using Pal's agar, which cannot be used in primary isolation. We have combined both media to obtain a new medium that can be used for the isolation and identification of C. dubliniensis in primary cultures. PMID:16272515

  2. Purification, crystallization and preliminary X-ray diffraction analysis of the carbohydrate-binding region of the Streptococcus gordonii adhesin GspB

    SciTech Connect

    Pyburn, Tasia M.; Yankovskaya, Victoria; Bensing, Barbara A.; Cecchini, Gary; Sullam, Paul M.; Iverson, T.M.

    2012-07-11

    The carbohydrate-binding region of the bacterial adhesin GspB from Streptococcus gordonii strain M99 (GspB{sub BR}) was expressed in Escherichia coli and purified using affinity and size-exclusion chromatography. Separate sparse-matrix screening of GspB{sub BR} buffered in either 20 mM Tris pH 7.4 or 20 mM HEPES pH 7.5 resulted in different crystallographic behavior such that different precipitants, salts and additives supported crystallization of GspB{sub BR} in each buffer. While both sets of conditions supported crystal growth in space group P2{sub 1}2{sub 1}2{sub 1}, the crystals had distinct unit-cell parameters of a = 33.3, b = 86.7, c = 117.9 {angstrom} for crystal form 1 and a = 34.6, b = 98.3, c = 99.0 {angstrom} for crystal form 2. Additive screening improved the crystals grown in both conditions such that diffraction extended to beyond 2 {angstrom} resolution. A complete data set has been collected to 1.3 {angstrom} resolution with an overall R{sub merge} value of 0.04 and an R{sub merge} value of 0.33 in the highest resolution shell.

  3. Azole resistance in Candida albicans.

    PubMed

    Smith, K J; Warnock, D W; Kennedy, C T; Johnson, E M; Hopwood, V; Van Cutsem, J; Vanden Bossche, H

    1986-04-01

    An isolate of Candida albicans from a patient with chronic mucocutaneous candidosis who relapsed during ketoconazole treatment was compared with a number of other azole-sensitive and azole-resistant isolates by tests in vitro and in three animal models of vaginal or disseminated infection. In-vitro tests indicated that the isolate was cross-resistant to all imidazole and triazole antifungals tested. In the animal models, treatment with miconazole, ketoconazole, itraconazole or fluconazole failed to influence the infection.

  4. DEVELOPMENT OF CANDIDA-ASSOCIATED DENTURE STOMATITIS: NEW INSIGHTS

    PubMed Central

    Pereira-Cenci, Tatiana; Cury, Altair Antoninha Del Bel; Crielaard, Wim; Cate, Jacob Martien ten

    2008-01-01

    Despite therapeutic progress, opportunistic oral fungal infectious diseases have increased in prevalence, especially in denture wearers. The combination of entrapment of yeast cells in irregularities in denture-base and denture-relining materials, poor oral hygiene and several systemic factors is the most probable cause for the onset of this infectious disease. Hence colonization and growth on prostheses by Candida species are of clinical importance. The purpose of this review is to critically discuss several key factors controlling the adhesion of Candida species which are relevant to denture-associated stomatitis. Although there is some consensus on the role of surface properties, studies on several other factors, as the use of denture liners, salivary properties and yeast-bacterial interactions, have shown contradictory findings. A comprehensive fundamental understanding is hampered by conflicting findings due to the large variations in experimental protocols, while other factors have never been thoroughly studied. Surface free energy and surface roughness control the initial adherence, but temporal changes have not been reported. Neither have in vivo studies shown if the substratum type is critical in dictating biofilm accumulation during longer periods in the oral environment. The contribution of saliva is unclear due to factors like variations in its collection and handling. Initial findings have disclosed that also bacteria are crucial for the successful establishment of Candida in biofilms, but the clinical significance of this observation is yet to be confirmed. In conclusion, there is a need to standardize experimental procedures, to bridge the gap between laboratory and in vivo methodologies and findings and – in general – to thoroughly investigate the factors that modulate the initial attachment and subsequent colonization of denture-base materials and the oral mucosa of patients subjected to Candida infections. Information on how these factors can

  5. Evaluation of Bichro-Dubli Fumouze to distinguish Candida dubliniensis from Candida albicans.

    PubMed

    Sahand, Ismail H; Moragues, María D; Robert, Raymond; Quindós, Guillermo; Pontón, José

    2006-06-01

    We have evaluated the ability of the Bichro-Dubli Fumouze (Fumouze Diagnostics, Levallois-Perret, France) latex agglutination test to identify colonies of Candida dubliniensis grown on different media. The test was positive for 103 of 106 isolates of C. dubliniensis and negative for Candida albicans and other Candida species studied. The sensitivity and specificity of the test were 97.1% and 100%, respectively. The test is very rapid, simple, and reliable giving the same results independently of whether the colonies are grown previously on Sabouraud dextrose agar, CHROMagar Candida medium, Candida ID2 medium, or CHROMagar-Pal's medium.

  6. 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

  7. Novel strategies to fight Candida species infection.

    PubMed

    Rodrigues, Maria Elisa; Silva, Sónia; Azeredo, Joana; Henriques, Mariana

    2016-08-01

    In recent years, there has been a significant increase in the incidence of human fungal infections. The increase in cases of infection caused by Candida species, and the consequent excessive use of antimicrobials, has favored the emergence of resistance to conventional antifungal agents over the past decades. Consequently, Candida infections morbidity and mortality are also increasing. Therefore, new approaches are needed to improve the outcome of patients suffering from Candida infections, because it seems unlikely that the established standard treatments will drastically lower the morbidity of mucocutaneous Candida infections and the high mortality associated with invasive candidiasis. This review aims to present the last advances in the traditional antifungal therapy, and present an overview of novel strategies that are being explored for the treatment of Candida infections, with a special focus on combined antifungal agents, antifungal therapies with alternative compounds (plant extracts and essential oils), adjuvant immunotherapy, photodynamic therapy and laser therapy.

  8. In vitro metabolic stability and intestinal transport of P57AS3 (P57) from Hoodia gordonii and its interaction with drug metabolizing enzymes.

    PubMed

    Madgula, Vamsi L M; Avula, Bharathi; Pawar, Rahul S; Shukla, Yatin J; Khan, Ikhlas A; Walker, Larry A; Khan, Shabana I

    2008-08-01

    Hoodia gordonii, a succulent cactus-like plant growing in South Africa, has been used in traditional medicine for its appetite suppressant properties. Its use as a dietary supplement to promote weight loss has recently gained popularity. An oxypregnane steroidal glycoside P57AS3 (P57) is reported to be the active constituent of the sap extract responsible for anorexigenic activity. No information is available about its metabolic stability, intestinal transport and interaction with drug metabolizing enzymes. In the present investigation, the metabolic stability of P57 in human liver microsomes and its interaction with drug metabolizing enzymes (CYP1A2, 2C9, 3A4 and 2D6) were determined. Intestinal transport of P57 was studied in the Caco-2 cell model of intestinal transport and absorption. P57 was metabolically stable in the presence of human liver microsomes. The compound inhibited CYP3A4 activity with an IC50 value of 45 microM, whereas the activity of CYP 1A2, 2C9 and 2D6 was not inhibited. In the Caco-2 model, P57 exhibited a higher transport in the secretory direction than in the absorptive direction with efflux ratios of 3.1 and 3.8 at 100 and 200 microM, respectively. The efflux was inhibited by selective inhibitors of multidrug resistance associated proteins MRP1/MRP2 (MK-571) and P-gp (verapamil). In conclusion, intestinal transport of P57 was mediated by P-gp and MRP transporters. The compound was metabolically stable and showed weak inhibition of CYP 3A4.

  9. Anti-Candida activity of Quercus infectoria gall extracts against Candida species

    PubMed Central

    Baharuddin, Nur Saeida; Abdullah, Hasmah; Abdul Wahab, Wan Nor Amilah Wan

    2015-01-01

    Background: Galls of Quercus infectoria have been traditionally used to treat common ailments, including yeast infections caused by Candida species. Objective: This study aimed to evaluate the in vitro anti-Candida activity of Q. infectoria gall extracts against selected Candida species. Materials and Methods: Methanol and aqueous extracts of Q. infectoria galls were tested for anti-Candida activity against Candida albicans, Candida krusei, Candida glabrata, Candida parapsilosis and Candida tropicalis. The minimum inhibitory concentrations were determined using the two-fold serial dilution technique of concentrations ranging from 16 mg/ml to 0.03 mg/ml. After 24 h, the minimum fungicidal concentrations were determined by subculturing the wells, which showed no turbidity on the agar plate. Potential phytochemical group in the crude extracts was screened by phytochemical qualitative tests and subsequently subjected to the gas chromatography-mass spectrometry analysis. Results: Both methanol and aqueous extracts displayed substantial anti-Candida activity and pyrogallol was the major component of both crude extracts. Conclusions: Data from current study suggested that Q. infectoria gall extracts are a potential source to be developed as anti-candidiasis. PMID:25709331

  10. 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

  11. Multi-species biofilm of Candida albicans and non-Candida albicans Candida species on acrylic substrate

    PubMed Central

    K PATHAK, Apurva; SHARMA, Sanjay; SHRIVASTVA, Pallavi

    2012-01-01

    Objective In polymicrobial biofilms bacteria extensively interact with Candida species, but the interaction among the different species of the Candida is yet to be completely evaluated. In the present study, the difference in biofilm formation ability of clinical isolates of four species of Candida in both single-species and multi-species combinations on the surface of dental acrylic resin strips was evaluated. Material and Methods The species of Candida, isolated from multiple species oral candidiasis of the neutropenic patients, were used for the experiment. Organisms were cultured on Sabouraud dextrose broth with 8% glucose (SDB). Biofilm production on the acrylic resins strips was determined by crystal violet assay. Student's t-test and ANOVA were used to compare in vitro biofilm formation for the individual species of Candida and its different multi-species combinations. Results In the present study, differences between the mean values of the biofilm-forming ability of individual species (C. glabrata>C. krusei>C. tropicalis>C. albicans) and in its multi-species' combinations (the highest for C. albicans with C. glabrata and the lowest for all the four species combination) were reported. Conclusions The findings of this study showed that biofilm-forming ability was found greater for non-Candida albicans Candida species (NCAC) than for C. albicans species with intra-species variation. Presence of C. albicans in multi-species biofilms increased, whereas; C. tropicalis decreased the biofilm production with all other NCAC species. PMID:22437681

  12. Hosting infection: experimental models to assay Candida virulence.

    PubMed

    Maccallum, Donna M

    2012-01-01

    Although normally commensals in humans, Candida albicans, Candida tropicalis, Candida parapsilosis, Candida glabrata, and Candida krusei are capable of causing opportunistic infections in individuals with altered physiological and/or immunological responses. These fungal species are linked with a variety of infections, including oral, vaginal, gastrointestinal, and systemic infections, with C. albicans the major cause of infection. To assess the ability of different Candida species and strains to cause infection and disease requires the use of experimental infection models. This paper discusses the mucosal and systemic models of infection available to assay Candida virulence and gives examples of some of the knowledge that has been gained to date from these models.

  13. Application of CHROMagar Candida for rapid screening of clinical specimens for Candida albicans, Candida tropicalis, Candida krusei, and Candida (Torulopsis) glabrata.

    PubMed Central

    Pfaller, M A; Houston, A; Coffmann, S

    1996-01-01

    CHROMagar Candida is a new differential culture medium that allows selective isolation of yeasts and simultaneously identifies colonies of Candida albicans, C. tropicalis, and C. krusei. We evaluated the use of this medium with 316 yeast isolates including 247 isolated directly on CHROMagar from clinical material. Over 95% of stock and clinical isolates of C. albicans, C. tropicalis, and C. krusei were correctly identified on the basis of colony morphology and pigmentation on CHROMagar. Additionally, CHROMagar also allowed the identification of C. (Torulopsis) glabrata at a similar level of accuracy. The overall agreement between two observers in reading the CHROMagar plates was 95%. Growth of Candida sp. isolates on CHROMagar had no adverse effect on antifungal MICs or Vitek identification results. In parallel, cultures of 548 stool and rectal swab specimens set up on CHROMagar and Sabouraud glucose agar (SGA) were positive in 234 instances. CHROMagar was positive and SGA was negative for 11 specimens, and CHROMagar was negative and SGA was positive for 18 specimens. A single yeast species was isolated on both media from 162 specimens, and in 146 (90%) of these specimens the same species was detected on both CHROMagar and SGA. A total of 43 of the 234 positive cultures contained mixtures of yeast species. Twenty (47%) of these mixed cultures were detected only on CHROMagar. CHROMagar is extremely useful in making a rapid presumptive identification of common yeast species. This capability plus the ability to detect mixed cultures of Candida spp. promises to improve and streamline the work flow in the mycology and clinical microbiology laboratory. PMID:8748273

  14. Microwave sterilization of Candida on underwear fabric. A preliminary report

    SciTech Connect

    Friedrich, E.G. Jr.; Phillips, L.E.

    1988-05-01

    Candida-contaminated underwear might not be sterilized by ordinary laundering. The effectiveness of microwaving against Candida albicans on fabric was therefore determined. Swatches of Candida-impregnated cotton underpants fabric were subjected to domestic microwaving at the high setting for up to 30 minutes. If the fabric was microwaved dry, the Candida organisms survived. If the fabric was moistened, sterilization occurred within five minutes. Microwaving wet, freshly laundered cotton underpants should sterilize residual Candida and reduce the risk of reinfection.

  15. Postantifungal effect of caspofungin against the Candida albicans and Candida parapsilosis clades.

    PubMed

    Gil-Alonso, Sandra; Jauregizar, Nerea; Eraso, Elena; Quindós, Guillermo

    2016-10-01

    Killing and postantifungal effects could be relevant for the selection of optimal dosing schedules. This study aims to compare time-kill and postantifungal effects with caspofungin on Candida albicans (C. albicans, Candida dubliniensis, Candida africana) and Candida parapsilosis (C. parapsilosis, Candida metapsilosis, Candida orthopsilosis) clades. In the postantifungal effect experiments, strains were exposed to caspofungin for 1 h at concentrations 0.12-8 μg/mL. Time-kill experiments were conducted at the same concentrations. Caspofungin exhibited a significant and prolonged postantifungal effect (>37 h) with 2 μg/mL against the most strains of C. albicans clade. Against the C. parapsilosis clade, the postantifungal effect was <12 h at 8 μg/mL, except for two strains. Caspofungin was fungicidal against C. albicans, C. dubliniensis and C. metapsilosis.

  16. Beyond Candida albicans: Mechanisms of immunity to non-albicans Candida species.

    PubMed

    Whibley, Natasha; Gaffen, Sarah L

    2015-11-01

    The fungal genus Candida encompasses numerous species that inhabit a variety of hosts, either as commensal microbes and/or pathogens. Candida species are a major cause of fungal infections, yet to date there are no vaccines against Candida or indeed any other fungal pathogen. Our knowledge of immunity to Candida mainly comes from studies on Candida albicans, the most frequent species associated with disease. However, non-albicans Candida (NAC) species also cause disease and their prevalence is increasing. Although research into immunity to NAC species is still at an early stage, it is becoming apparent that immunity to C. albicans differs in important ways from non-albicans species, with important implications for treatment, therapy and predicted demographic susceptibility. This review will discuss the current understanding of immunity to NAC species in the context of immunity to C. albicans, and highlight as-yet unanswered questions.

  17. 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

  18. Differentiation between Atypical Isolates of Candida lusitaniae and Candida pulcherrima by Determination of Mating Type

    PubMed Central

    Noël, Thierry; Favel, Anne; Michel-Nguyen, Annie; Goumar, Abdelhak; Fallague, Karim; Chastin, Christiane; Leclerc, Florence; Villard, Jean

    2005-01-01

    We report on five clinical isolates routinely identified as Candida lusitaniae that the ID 32C system was unable to discriminate from the closely related species Candida pulcherrima. When additional tests did not allow accurate identification, the less usual mating type test identified all of them as Clavispora lusitaniae. Mating type testing appears to be a valuable tool for assessing the true incidence of this emerging non-albicans Candida species. PMID:15750124

  19. Folsomia candida (Collembola): a "standard" soil arthropod.

    PubMed

    Fountain, Michelle T; Hopkin, Steve P

    2005-01-01

    Folsomia candida Willem 1902, a member of the order Collembola (colloquially called springtails), is a common and widespread arthropod that occurs in soils throughout the world. The species is parthenogenetic and is easy to maintain in the laboratory on a diet of granulated dry yeast. F. candida has been used as a "standard" test organism for more than 40 years for estimating the effects of pesticides and environmental pollutants on nontarget soil arthropods. However, it has also been employed as a model for the investigation of numerous other phenomena such as cold tolerance, quality as a prey item, and effects of microarthropod grazing on pathogenic fungi and mycorrhizae of plant roots. In this comprehensive review, aspects of the life history, ecology, and ecotoxicology of F. candida are covered. We focus on the recent literature, especially studies that have examined the effects of soil pollutants on reproduction in F. candida using the protocol published by the International Standards Organization in 1999.

  20. Development of DNA probes for Candida albicans

    SciTech Connect

    Cheung, L.L.; Hudson, J.B.

    1988-07-01

    An attempt was made to produce DNA probes that could be used as a rapid and efficient means of detecting candidiasis (invasive Candida infection) in immunocompromised patients. Whole DNA from Candida albicans was digested with restriction endonuclease, and the resulting fragments were randomly cloned into a plasmid vector. Several recombinant plasmids were evaluated for cross-hybridization to various other Candida species, other fungal DNAs, and to nonfungal DNAs. Cross reactions were observed between the probes and different yeasts, but none with unrelated DNAs. Some recombinants were genus-specific, and two of these were applied to the analysis of C. albicans growth curves. It became evident that, although both /sup 32/P- and biotin-labelled probes could be made quite sensitive, a possible limitation in their diagnostic potential was the poor liberation of Candida DNA from cells. Thus, better methods of treatment of clinical specimens will be required before such probes will be useful in routine diagnosis.

  1. Candida utilis catheter-related bloodstream infection

    PubMed Central

    Scoppettuolo, Giancarlo; Donato, Concetta; De Carolis, Elena; Vella, Antonietta; Vaccaro, Luisa; La Greca, Antonio; Fantoni, Massimo

    2014-01-01

    Central venous catheter-related fungemia are increasing in the last years, also due to rare fungi. We report the case of a Candida utilis catheter-related bloodstream infection in a patient with metastatic carcinoma of the bladder and a long term totally implanted venous catheter. The diagnosis was done by paired blood cultures and differential time to positivity. The Candida species was rapidly identified by MALDI-TOF mass spectrometry. The patient was successfully treated with anidulafungine. PMID:25473600

  2. Beta-defensin 1 plays a role in acute mucosal defense to Candida albicans

    PubMed Central

    Tomalka, Jeffrey; Azodi, Elaheh; Narra, Hema P.; Patel, Krupen; O’Neill, Samantha; Cardwell, Cisley; Hall, Brian A.; Wilson, James M.; Hise, Amy G.

    2015-01-01

    Candida is an opportunistic fungal pathogen that colonizes the mucosal tract of humans. Pathogenic infection occurs in the presence of conditions causing perturbations to the commensal microbiota or host immunity. Early innate immune responses by the epithelium, including antimicrobial peptides (AMPs) and cytokines, are critical for protection against overgrowth. Reduced salivary AMP levels are associated with oral Candida infection and certain AMPs, including human beta-defensins 1 - 3, have direct fungicidal activity. Here we demonstrate that murine β-Defensin 1 (mBD1) is important for control of early mucosal Candida infection and plays a critical role in the induction of innate inflammatory mediators. Mice deficient in mBD1 exhibit elevated oral and systemic fungal burdens as compared to wild-type mice. Neutrophil infiltration to the sites of mucosal Candida invasion, an important step in limiting fungal infection, is significantly reduced in mBD1 deficient mice. These mice also exhibit defects in the expression of other antimicrobial peptides, including mBD2 and mBD4, which may have direct anti-Candida activity. We also show that mBD1 deficiency impacts the production of important anti-fungal inflammatory mediators including IL-1β, IL-6, KC, and IL-17. Collectively, these studies demonstrate a role for the mBD1 peptide in early control of Candida infection in a murine model of mucosal candidiasis, as well as on the modulation of host immunity through augmentation of leukocyte infiltration and inflammatory gene induction. PMID:25595775

  3. Candida glabrata survives and replicates in human osteoblasts.

    PubMed

    Muñoz-Duarte, Ana Rosa; Castrejón-Jiménez, Nayeli Shantal; Baltierra-Uribe, Shantal Lizbeth; Pérez-Rangel, Sofia Judith; Carapia-Minero, Natalee; Castañeda-Sánchez, Jorge Ismael; Luna-Herrera, Julieta; López-Santiago, Rubén; Rodríguez-Tovar, Aída Verónica; García-Pérez, Blanca Estela

    2016-06-01

    Candida glabrata is an opportunistic pathogen that is considered the second most common cause of candidiasis after Candida albicans Many characteristics of its mechanisms of pathogenicity remain unknown. Recent studies have focused on determining the events that underlie interactions between C. glabrata and immune cells, but the relationship between this yeast and osteoblasts has not been studied in detail. The aim of this study was to determine the mechanisms of interaction between human osteoblasts and C. glabrata, and to identify the roles played by some of the molecules that are produced by these cells in response to infection. We show that C. glabrata adheres to and is internalized by human osteoblasts. Adhesion is independent of opsonization, and internalization depends on the rearrangement of the actin cytoskeleton. We show that C. glabrata survives and replicates in osteoblasts and that this intracellular behavior is related to the level of production of nitric oxide and reactive oxygen species. Opsonized C. glabrata stimulates the production of IL-6, IL-8 and MCP-1 cytokines. Adhesion and internalization of the pathogen and the innate immune response of osteoblasts require viable C. glabrata These results suggest that C. glabrata modulates immunological mechanisms in osteoblasts to survive inside the cell.

  4. Candida albicans in oral biofilms could prevent caries.

    PubMed

    Willems, Hubertine Marjoleine; Kos, Kevin; Jabra-Rizk, Mary Ann; Krom, Bastiaan P

    2016-07-01

    Streptococcus mutans is a Gram-positive bacterium involved in development to caries, the most common infectious disease of our time. Streptococcus mutans interacts with other microbes, like the fungus Candida albicans and both are commonly isolated from patients with caries. Since the role of C. albicans in caries remains unknown, our aim was to unravel this using an in vitro dual-species cariogenic oral biofilm model. Biofilms were grown for 24-72 h on glass cover slips or hydroxyapatite (HA) disks to mimic the surface of teeth. Medium pH, lactic acid production capacity and calcium release from HA disks were determined. All 24-h biofilms had external pH values below the critical pH of 5.5 where enamel dissolves. In contrast, 72-h dual-species biofilms had significantly higher pH (above the critical pH) and consequently decreased calcium release compared to single-species S. mutans biofilms. Counter intuitively, lactic acid production and growth of S. mutans were increased in 72-h dual-species biofilms. Candida albicans modulates the pH in dual-species biofilms to values above the critical pH where enamel dissolves. Our results suggest that C. albicans is not by definition a cariogenic microorganism; it could prevent caries by actively increasing pH preventing mineral loss.

  5. Candida albicans biofilm on titanium: effect of peroxidase precoating

    PubMed Central

    Ahariz, Mohamed; Courtois, Philippe

    2010-01-01

    The present study aimed to document Candida albicans biofilm development on titanium and its modulation by a peroxidase-precoated material which can generate antimicrobials, such as hypoiodite or hypothiocyanite, from hydrogen peroxide, iodide, or thiocyanate. For this purpose, titanium (powder or foil) was suspended in Sabouraud liquid medium inoculated with C. albicans ATCC10231. After continuous stirring for 2–21 days at room temperature, the supernatant was monitored by turbidimetry at 600 nm and titanium washed three times in sterile Sabouraud broth. Using the tetrazolium salt MTT-formazan assay, the titanium-adherent fungal biomass was measured as 7.50 ± 0.60 × 106 blastoconidia per gram of titanium powder (n = 30) and 0.50 ± 0.04 × 106 blastoconidia per cm2 of titanium foil (n = 12). The presence of yeast on the surface of titanium was confirmed by microscopy both on fresh preparations and after calcofluor white staining. However, in the presence of peroxidase systems (lactoperoxidase with substrates such as hydrogen peroxide donor, iodide, or thiocyanate), Candida growth in both planktonic and attached phases appeared to be inhibited. Moreover, this study demonstrates the possible partition of peroxidase systems between titanium material (peroxidase-precoated) and liquid environment (containing peroxidase substrates) to limit C. albicans biofilm formation. PMID:22915919

  6. Candida glabrata among Candida spp. from environmental health practitioners of a Brazilian Hospital.

    PubMed

    Savastano, Catarina; de Oliveira Silva, Elisa; Gonçalves, Lindyanne Lemos; Nery, Jéssica Maria; Silva, Naiara Chaves; Dias, Amanda Latercia Tranches

    2016-01-01

    The incidence of the species Candida albicans and non-albicans Candida was evaluated in a Brazilian Tertiary Hospital from the environment and health practitioners. In a 12-month period we had a total positivity of 19.65% of Candida spp. The most recurring non-albicans Candida species was C. glabrata (37.62%), generally considered a species of low virulence, but with a higher mortality rate than C. albicans. Subsequently, C. parapsilosis (25.74%) and C. tropicalis (16.86%) were the second and third most commonly isolated species. Considering the total samples collected from the emergency room and from the inpatient and the pediatric sector, 19.10% were positive for Candida spp., with the predominance of non-albicans Candida species (89.42%). The high percentage of positivity occurred in the hands (24.32%) and the lab coats (21.88%) of the health care assistants. No sample of C. albicans presented a profile of resistance to the drugs. All the non-albicans Candida species presented a decreased susceptibility to miconazole and itraconazole, but they were susceptible to nystatin. Most of the isolates were susceptible to fluconazole and amphotericin B. As expected, a high resistance rate was observed in C. glabrata and C. krusei, which are intrinsically less susceptible to this antifungal agent. The contamination of environmental surfaces by Candida spp. through hand touching may facilitate the occurrence of Candida infections predominantly in immunocompromised patients. In addition to that, the antifungal agents used should be carefully evaluated considering local epidemiologic trends in Candida spp. infections, so that therapeutic choices may be better guided.

  7. 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)).

  8. [Taxonomy and ecology of the genus Candida].

    PubMed

    Schauer, F; Hanschke, R

    1999-01-01

    Candida is a heterogeneous genus which contains about a quarter of all yeast species. It includes not only species of uncertain affiliation but also unrelated strains whose phylogenetic relationships have not been resolved. A great variety of CoQ types are present in the genus, the mol % G + C ranges from 30-63%, and species that were found to sporulate have teleomorphic counterparts in 11 different genera. Candida species are mainly associated with plants, rotting vegetation, with insects which feed on plants or with food. In line with this, 71% of Candida species utilize xylose (wood degradation), 57% of species use cellobiose (cellulose degradation), 29% oxidize aliphatic hydrocarbons (components of plant cuticula), 27% of species degrade starch as a plant storage material, and 7% utilize methanol as a possible metabolite from pectin catabolism. 85% of species require individual vitamins produced mainly in plant materials. 65% of Candida species are not able to grow at temperatures of 37 degrees C. In comparison only relatively few species occur normally in humans and other warm blooded animals. About 16% of type strains and selected strains for comparative purposes (CBS) were isolated from human specimens. Perhaps up to 10% of Candida species may be of medical importance, though this has so far only been clearly demonstrated for less than 5% of currently known species.

  9. Killer behavior within the Candida parapsilosis complex.

    PubMed

    Robledo-Leal, Efrén; Elizondo-Zertuche, Mariana; Villarreal-Treviño, Licet; Treviño-Rangel, Rogelio de J; García-Maldonado, Nancy; Adame-Rodríguez, Juan M; González, Gloria M

    2014-11-01

    A group of 29 isolates of Candida parapsilosis sensu stricto, 29 of Candida orthopsilosis, and 4 of Candida metapsilosis were assayed for the presence of killer activity using Saccharomyces cerevisiae ATCC 26609 as a sensitive strain. All C. metapsilosis isolates showed killer activity at 25 °C while strains of C. parapsilosis sensu stricto or C. orthopsilosis did not exhibit this activity. Sensitivity to killer toxins was evaluated using a set of previously reported killer strains of clinical origin. Only 11 isolates of the C. parapsilosis complex were inhibited by at least one killer isolate without resulting in any clear pattern, except for C. parapsilosis sensu stricto ATCC 22019, which was inhibited by every killer strain with the exception of C. parapsilosis and Candida utilis. The lack of sensitivity to killer activity among isolates of the genus Candida suggests that their toxins belong to the same killer type. Differentiation of species within the C. parapsilosis complex using the killer system may be feasible if a more taxonomically diverse panel of killer strains is employed.

  10. Evaluation of Candida Colonization and Specific Humoral Responses against Candida albicans in Patients with Atopic Dermatitis

    PubMed Central

    Javad, Ghaffari; Taheri Sarvtin, Mehdi; Hedayati, Mohammad Taghi; Hajheydari, Zohreh; Yazdani, Jamshid; Shokohi, Tahereh

    2015-01-01

    The aim of this study was to assess the candidal colonization and specific humoral responses against Candida albicans in patients with atopic dermatitis. One hundred patients with atopic dermatitis and 50 healthy individuals were enrolled in the study. Skin and oral specimens from all participants were cultured on CHROMagar Candida medium. Isolated yeasts were identified by using the sequence of the D1/D2 domain of the 26S rRNA gene. ELISA was used for detection of IgM, IgA, and IgG antibodies against C. albicans in sera of participants. Candida species were isolated from the skin and oral cavity of 31% of the patients and 12% of the controls. There was no significant difference between Candida colonization in patients and controls (P>0.05). Candida albicans was isolated from the skin and oral cavity of 23% of the patients and 6% of the controls (P< 0.05). There were no significant differences between serum levels of IgM and IgA in patients and controls (P>0.05). Serum level of IgG was significantly lower in patients than in controls (P<0.05). Type of Candida colonization can change in patients with atopic dermatitis. In addition, these patients have abnormalities in the production of antibodies against Candida albicans that may have a role in the pathogenesis of atopic dermatitis. PMID:25945349

  11. Non-albicans Candida Infection: An Emerging Threat

    PubMed Central

    Deorukhkar, Sachin C.; Saini, Santosh

    2014-01-01

    The very nature of infectious diseases has undergone profound changes in the past few decades. Fungi once considered as nonpathogenic or less virulent are now recognized as a primary cause of morbidity and mortality in immunocompromised and severely ill patients. Candida spp. are among the most common fungal pathogens. Candida albicans was the predominant cause of candidiasis. However, a shift toward non-albicans Candida species has been recently observed. These non-albicans Candida species demonstrate reduced susceptibility to commonly used antifungal drugs. In the present study, we investigated the prevalence of non-albicans Candida spp. among Candida isolates from various clinical specimens and analysed their virulence factors and antifungal susceptibility profile. A total of 523 Candida spp. were isolated from various clinical specimens. Non-albicans Candida species were the predominant pathogens isolated. Non-albicans Candida species also demonstrated the production of virulence factors once attributed to Candida albicans. Non-albicans Candida demonstrated high resistance to azole group of antifungal agents. Therefore, it can be concluded that non-albicans Candida species have emerged as an important cause of infections. Their isolation from clinical specimen can no longer be ignored as a nonpathogenic isolate nor can it be dismissed as a contaminant. PMID:25404942

  12. How to use the Candida Genome Database

    PubMed Central

    Skrzypek, Marek S.; Binkley, Jonathan; Sherlock, Gavin

    2016-01-01

    Summary Studying Candida biology requires access to genomic sequence data in conjunction with experimental information that provides functional context to genes and proteins. The Candida Genome Database (CGD) integrates functional information about Candida genes and their products with a set of analysis tools that facilitate searching for sets of genes and exploring their biological roles. This chapter describes how the various types of information available at CGD can be searched, retrieved, and analyzed. Starting with the guided tour of the CGD Home page and Locus Summary page, this unit shows how to navigate the various assemblies of the C. albicans genome, how to use Gene Ontology tools to make sense of large-scale data, and how to access the microarray data archived at CGD. PMID:26519061

  13. Caspofungin at catheter lock concentrations eradicates mature biofilms of Candida lusitaniae and Candida guilliermondii.

    PubMed

    Simitsopoulou, Maria; Kyrpitzi, Daniela; Velegraki, Aristea; Walsh, Thomas J; Roilides, Emmanuel

    2014-08-01

    The antibiofilm activities of caspofungin, anidulafungin, micafungin, and liposomal amphotericin B were studied against Candida lusitaniae, Candida guilliermondii, and a Candida albicans control strain. While anidulafungin and micafungin (0.007 to 2,048 mg/liter) showed reduced activity against biofilms of both test species, caspofungin displayed concentration-dependent antibiofilm activity, reaching complete and persistent eradication at concentrations achievable during lock therapy (512 to 2,048 mg/liter, P < 0.05). Although liposomal amphotericin B strongly inhibited mature biofilms, it possessed lower antibiofilm activity than caspofungin (P < 0.05).

  14. 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

  15. Candida albicans isolates from a Malaysian hospital exhibit more potent phospholipase and haemolysin activities than non-albicans Candida isolates.

    PubMed

    Chin, V K; Foong, K J; Maha, A; Rusliza, B; Norhafizah, M; Ng, K P; Chong, P P

    2013-12-01

    This study was aimed at determining the phospholipase and haemolysin activity of Candida isolates in Malaysia. A total of 37 Candida clinical isolates representing seven species, Candida albicans (12), Candida tropicalis (8), Candida glabrata (4), Candida parapsilosis (1), Candida krusei (4), Candida orthopsilosis (1) and Candida rugosa (7) were tested. In vitro phospholipase activity was determined by using egg yolk plate assay whereas in vitro haemolysin activity was tested by using blood plate assay on sheep blood Sabouraud's dextrose agar (SDA) enriched with glucose. Phospholipase activity was detected in 75% (9 out of 12) of the C. albicans isolates. Among the 25 non- C. albicans Candida isolates, phospholipase activity was detected in only 24% of these isolates. The phospholipase activity of C. albicans was significantly higher than that of the non- C. albicans Candida isolates (P=0.002). Haemolysin activity was detected in 100% of the C. albicans, C. tropicalis, C. glabrata, C. krusei, C. parapsilosis, and C. orthopsilosis isolates while 75% of the C. krusei isolates and 12.3% of the C. rugosa isolates showed haemolysin activity. The haemolytic activity of C. albicans was significantly higher than that of the non- C. albicans Candida isolates (P=0.0001).The findings in this study indicate that C. albicans isolates in Malaysia may possess greater virulence potential than the non-albicans species.

  16. Genetic diversity of the yeast Candida utilis.

    PubMed

    Stoltenburg, R; Klinner, U; Ritzerfeld, P; Zimmermann, M; Emeis, C C

    1992-12-01

    The electrophoretic karyotypes and some mtDNA restriction fragment patterns of 13 strains of Candida utilis and one strain of Hansenula jadinii were compared. PFGE separations revealed remarkable chromosome length polymorphisms between two groups of strains suggesting that perhaps they do not belong to the same species. However, all strains had the same or similar EcoRI, HindIII and BamHI mtDNA restriction patterns. The mtDNA genomes had an average size range of 55 kb. These results support the supposition that C. utilis is a yeast with a highly variable electrophoretic karyotype as already known for another imperfect yeast species, Candida albicans.

  17. Protection of mice from oral Candidiasis by heat-killed enterococcus faecalis, possibly through its direct binding to Candida albicans.

    PubMed

    Ishijima, Sanae A; Hayama, Kazumi; Ninomiya, Kentaro; Iwasa, Masahiro; Yamazaki, Masatoshi; Abe, Shigeru

    2014-01-01

    To develop a new therapy against oral candidiasis, a commensal microorganism, Enterococcus faecalis was tested for its ability to modulate Candida growth in vitro and its therapeutic activities against a murine model in vivo. Addition of heat-killed E. faecalis strain EF2001 (EF2001) isolated from healthy human feces to the culture of C. albicans strain TIMM1768 inhibited adherence of the latter to a microtiter plate in a dose dependent manner and Candida cells surrounded by EF2001 were increased. To examine the protective activities of EF2001 in vivo, heat-killed EF2001 was applied orally before and after inoculation of Candida to the tongue of mice previously immunosuppressed. Two days after inoculation this inoculation, both the symptom score and CFU from swabbed-tongue were significantly reduced in the EF2001-treated animals. Histological analysis indicated that EF2001 may potentiate the accumulation of polymorphnuclear cells near a Candida-infected region. These results suggest that oral administration of EF2001 has protective activity against oral candidiasis and that the in vivo activity may be reflected by direct interaction between EF2001 and Candida cells in vitro and the potentiation of an immunostimulatory effect of EF2001.

  18. The Host’s Reply to Candida Biofilm

    PubMed Central

    Nett, Jeniel E.

    2016-01-01

    Candida spp. are among the most common nosocomial fungal pathogens and are notorious for their propensity toward biofilm formation. When growing on a medical device or mucosal surface, these organisms reside as communities embedded in a protective matrix, resisting host defenses. The host responds to Candida biofilm by depositing a variety of proteins that become incorporated into the biofilm matrix. Compared to free-floating Candida, leukocytes are less effective against Candida within a biofilm. This review highlights recent advances describing the host’s response to Candida biofilms using ex vivo and in vivo models of mucosal and device-associated biofilm infections. PMID:26999221

  19. [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.

  20. Comparison of the susceptibilities of clinical isolates of Candida albicans and Candida dubliniensis to essential oils.

    PubMed

    Pozzatti, Patrícia; Loreto, Erico Silva; Lopes, Paulo Guilherme Markus; Athayde, Margareth Linde; Santurio, Janio Morais; Alves, Sydney Hartz

    2010-01-01

    Here, a microdilution technique based on the M27-A2 protocol (NCCLS, 2002) was employed to compare the susceptibilities of Candida albicans and Candida dubliniensis to essential oils extracted from plants used as spices. The chemical compositions of the essential oils were defined based on the analysis of retention indices obtained by gas chromatography-mass spectroscopy. Taken together, the results showed that the activity of the compounds against the two species was similar.

  1. Serological Differentiation of Experimentally Induced Candida dubliniensis and Candida albicans Infections

    PubMed Central

    Moragues, María D.; Omaetxebarria, Miren J.; Elguezabal, Natalia; Bikandi, Joseba; Quindós, Guillermo; Coleman, David C.; Pontón, José

    2001-01-01

    Using a rabbit model of systemic infection, we show that it is possible to differentiate infections caused by Candida dubliniensis and other Candida species by detecting the antibody response mounted by the infected animals. These results confirm our previous observation in a patient with C. dubliniensis candidemia and suggest that detection of C. dubliniensis-specific antibodies is useful in the diagnosis of invasive candidiasis caused by this yeast. PMID:11474033

  2. In vitro activity of Caspofungin combined with Fluconazole on mixed Candida albicans and Candida glabrata biofilm.

    PubMed

    Pesee, Siripen; Angkananuwat, Chayanit; Tancharoensukjit, Sudarat; Muanmai, Somporn; Sirivan, Pattaraporn; Bubphawas, Manita; Tanarerkchai, Nissara

    2016-05-01

    The objective of this study was to evaluate the antifungal effect of caspofungin (CAS) combined with fluconazole (FLU) on the biofilm biomass and cultivable viability and microstructure of Candida albicans and Candida glabrata mixed biofilm in vitro.Biofilms were formed in a 96-well microtiter plate for crystal violet assay and colony forming unit (CFU) method and grown on plastic coverslip disks for scanning electron microscopy. MIC50 of CAS and FLU against single Candida spp.and mixed Candida spp.biofilms were evaluated using crystal violet assay. Additional,C. albicans and C. glabrata mixed biofilms were incubated with subinhibitory CAS concentration plus FLU and their percentages of Candida biofilm reduction were calculated. We found that percentages of biofilm reduction were significantly decreased when CAS at 0.25MIC and FLU (0.25 or 0.5MIC) were combined (P< .05) but not different when CAS at 0.5 MIC combined with FLU at 0.25 or 0.5MIC, compared to CAS treatment alone. Structural analyses revealed that CAS/FLU combination-treated biofilms showed less hyphae and blastospores with some aberrant cells compared to control group. Although it was evident that a greater CFU of Candida glabrata were demonstrated in every group, the total viable cells derived from CAS/FLU combination-treated biofilms at any ratio were not significantly different from positive control. Overall, CAS/FLU combinations appeared to affect the quantity and cell architecture, but number of viable cell, of Candida albicans and Candida glabrata mixed biofilm. This antifungal effect was CAS concentration dependent.

  3. Antifungal drug resistance among Candida species: mechanisms and clinical impact.

    PubMed

    Sanguinetti, Maurizio; Posteraro, Brunella; Lass-Flörl, Cornelia

    2015-06-01

    The epidemiology of Candida infections has changed in recent years. Although Candida albicans is still the main cause of invasive candidiasis in most clinical settings, a substantial proportion of patients is now infected with non-albicans Candida species. The various Candida species vary in their susceptibility to the most commonly used antifungal agents, and the intrinsic resistance to antifungal therapy seen in some species, along with the development of acquired resistance during treatment in others, is becoming a major problem in the management of Candida infection. A better understanding of the mechanisms and clinical impact of antifungal drug resistance is essential for the efficient treatment of patients with Candida infection and for improving treatment outcomes. Herein, we report resistance to the azoles and echinocandins among Candida species.

  4. Defining pheromone-receptor signaling in Candida albicans and related asexual Candida species.

    PubMed

    Lin, Ching-Hsuan; Choi, Anthony; Bennett, Richard J

    2011-12-01

    Candida albicans is an important human fungal pathogen in which sexual reproduction is under the control of the novel white-opaque switch. Opaque cells are the mating-competent form, whereas white cells do not mate but can still respond to pheromones, resulting in biofilm formation. In this study, we first define the domains of the α-pheromone receptor Ste2 that are necessary for signaling in both white and opaque forms. Both cell states require the IC loop 3 (IC3) and the C-terminal tail of Ste2 for the cellular response, whereas the first IC loop (IC1) of Ste2 is dispensable for signaling. To also address pheromone-receptor interactions in related species, including apparently asexual Candida species, Ste2 orthologues were heterologously expressed in Candida albicans. Ste2 receptors from multiple Candida clade species were functional when expressed in C. albicans, whereas the Ste2 receptor of Candida lusitaniae was nonfunctional. Significantly, however, expression of a chimeric C. lusitaniae Ste2 receptor containing the C-terminal tail of Ste2 from C. albicans generated a productive response to C. lusitaniae pheromone. This system has allowed us to characterize pheromones from multiple Candida species and indicates that functional pheromone-receptor couples exist in fungal species that have yet to be shown to undergo sexual mating.

  5. 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

  6. Melaleuca alternifolia nanoparticles against Candida species biofilms.

    PubMed

    Souza, M E; Lopes, L Q S; Bonez, P C; Gündel, A; Martinez, D S T; Sagrillo, M R; Giongo, J L; Vaucher, R A; Raffin, R P; Boligon, A A; Santos, R C V

    2017-03-01

    Candida infection is an important cause of morbidity and mortality on immunosuppressed patients. This growing trend has been associated with resistance to the antimicrobial therapy and the ability of microorganism to form biofilms. TTO oil is used as antimicrobial which shows antibiofilm activity against Candida species. However, it presents problems due to its poor solubility and high volatility. The present study aimed to evaluate in vitro antibiofilm activity of TTO nanoparticles against many Candida species. It was performed the characterization of the oil and nanoparticles. The levels of exopolysaccharides, proteins, and the biomass of biofilms were measured. The chromatographic profile demonstrated that the TTO oil is in accordance with ISO 4730 with major constituents of 41.9% Terpinen-4-ol, 20.1% of γ-Terpinene, 9,8% of α-Terpinene, and 6,0% of 1,8-Cineole. The TTO nanoparticles showed pH of 6.3, mean diameter of 158.2 ± 2 nm, polydispersion index of 0.213 ± 0.017, and zeta potential of -8.69 ± 0.80 mV. The addition of TTO and its nanoparticles represented a significant reduction of biofilm formed by all Candida species, as well as a reduction of proteins and exopolysaccharides levels. It was possible to visualize the reduction of biofilm in presence of TTO nanoparticles by Calcofluor White method.

  7. Four new Amaryllidaceae alkaloids from Zephyranthes candida.

    PubMed

    Shitara, Nanase; Hirasawa, Yusuke; Hasumi, Shunsuke; Sasaki, Tadahiro; Matsumoto, Misaki; Wong, Chin Piow; Kaneda, Toshio; Asakawa, Yoshinori; Morita, Hiroshi

    2014-07-01

    Four new Amaryllidaceae alkaloids (1-4) possessing a homolycorine-type or a crinine-type skeleton have been isolated from the aerial part of Zephyranthes candida, and their structures were elucidated on the basis of spectroscopic data. The stereochemistry was elucidated by combination of NOESY correlations and CD analyses.

  8. Phospholipase and proteinase activities of Candida isolates from denture wearers.

    PubMed

    Marcos-Arias, Cristina; Eraso, Elena; Madariaga, Lucila; Aguirre, Jose Manuel; Quindós, Guillermo

    2011-07-01

    The aim of the present study was to characterise phospholipase and proteinase activities of oral Candida isolates from 100 denture wearers and to study the relationship of these activities with denture stomatitis. Of 100 patients studied, 44 suffered from denture stomatitis. Specimens were collected by swabbing the denture and underlying mucosa. Isolates were previously identified by conventional mycological and genotypic methods. The phospholipase and proteinase activities were evaluated by agar plate methods. A total of 152 isolates were recovered from denture and underlying mucosa, including 101 Candida albicans, 18 Candida tropicalis, 14 Candida glabrata, 11 Candida guilliermondii, four Candida parapsilosis, two Saccharomyces cerevisiae and one isolate each of Candida dubliniensis and Candida krusei. Most C. albicans (97%) showed phospholipase activity; furthermore, the unique C. dubliniensis isolate showed a moderate phospholipase activity. The isolation of C. albicans (chi-square test, P = 0.0016) and phospholipase production by Candida spp. (chi-square test, P = 0.0213) was found to be significantly associated with denture stomatitis. Proteinase production was observed in <30% of isolates, and it was not related to the presence of denture stomatitis (P = 0.7675). Candida albicans isolates may produce both virulence factors, although the proteinase production was only observed in <30% of the isolates. Phospholipase production was exclusive of C. albicans and C. dubliniensis.

  9. Candida albicans and non-Candida albicans fungemia in an institutional hospital during a decade.

    PubMed

    Parmeland, Laurence; Gazon, Mathieu; Guerin, Claude; Argaud, Laurent; Lehot, Jean-Jacques; Bastien, Olivier; Allaouchiche, Bernard; Michallet, Mauricette; Picot, Stephane; Bienvenu, Anne-Lise

    2013-01-01

    Since the outcomes of patients with candidemia is poor and Candida spp. with increased resistance to antifungal therapy may be associated with these results, the emergence of these blood infections caused by non-C. albicans Candida spp. was explored prospectively over a two-year period (2009-2010). Candidemia was defined as the recovery of Candida spp. in culture from a patient's blood sample. The in vitro susceptibility of each isolate to amphotericin B, caspofungin, fluconazole and voriconazole was determined. In addition, characteristics of patients and outcomes were investigated in real-time. The Candida distribution was compared to that observed in a similar study 10 years earlier in the same hospital. A total of 182 patients with candidemia were included in the study. While C. albicans was the most frequently isolated species (n = 102), non-C. albicans Candida spp. included; C. glabrata (n = 32), C. parapsilosis (n = 21), C. tropicalis (n = 13), C. krusei (n = 8), C. kefyr (n = 3), C. lusitaniae (n = 2), C. lipolytica (n = 2), C. famata (n = 1), C. guilliermondii (n = 1), C. inconspicua (n = 1), C. dubliniensis (n = 1), C. sake (n = 1) and C. nivariensis (n = 1). In seven patients, C. albicans was associated with another Candida spp. Surprisingly, this prospective study demonstrated that regardless of the department (intensive care unit or hematological department), Candida spp. distribution was no different from that found in the 1998-2001 survey, except for C. krusei. A reduction in the proportion of C. krusei isolates was observed from 2000-2010 (P = 0.028) as a result of its decreased recovery in the hematological department.

  10. Candida heliconiae sp. nov., Candida picinguabensis sp. nov. and Candida saopaulonensis sp. nov., three ascomycetous yeasts from Heliconia velloziana (Heliconiaceae).

    PubMed

    Ruivo, Carla C C; Lachance, Marc-André; Rosa, Carlos A; Bacci, Maurício; Pagnocca, Fernando C

    2006-05-01

    Strains belonging to three novel yeast species, Candida heliconiae (four isolates), Candida picinguabensis (three isolates) and Candida saopaulonensis (two isolates), were recovered in the year 2000 from water of flower bracts of Heliconia velloziana L. Emigd. (Heliconiaceae) found in a forest ecosystem site in an Atlantic rainforest of south-eastern Brazil. C. picinguabensis and C. saopaulonensis were nearly identical in morphology and physiology, but sequence divergence in the D1/D2 domain of the large-subunit rDNA indicated that they should be regarded as different species. They belong to the Metschnikowiaceae clade. C. heliconiae had affinities to Pichia mexicana and related species, but was genetically isolated from all currently accepted species in that group. The type strains are C. heliconiae UNESP 00-91C1T (=CBS 10000T=NRRL Y-27813T), C. picinguabensis UNESP 00-89T (=CBS 9999T=NRRL Y-27814T) and C. saopaulonensis UNESP 00-99T (=CBS 10001T=NRRL Y-27815T).

  11. [Prevalence of Candida albicans and Candida non-albicans in clinical samples during 1999-2001].

    PubMed

    Mujica, M T; Finquelievich, J L; Jewtuchowicz, V; Iovannitti, C A

    2004-01-01

    The importance of epidemiological monitoring of yeasts involved in pathologic processes is unquestionable due to the increase of these infections over the last decade, the changes observed in species causing candidiasis, and empirical antifungal treatment. At the Mycology Center, 1006 isolates from a wide range of clinical samples were studied during 1999-2001. Candida albicans (40.3%) was the most isolated species, although, the Candida no albicans species with 54.9% showed the major prevalence. In blood cultures Candida parapsilosis (34.9%), C. albicans (30.2%) and C. tropicalis (25.6%) were recovered most frequently while C. glabrata represented only 2.3%. C. albicans with 60%-80% was the predominant specie in mucosal surface. We also detected Candida mediastinistis, which alert us over the importance at this location. Urinary tract infections caused by yeasts were more frequent in hospitalized patients, being C. albicans (47.7%), the most commonly isolated, followed by C. glabrata (24.8%) and C. tropicalis (20.0%). In the candidal onychomycoses, C. parapsilosis (37.7%) outplaced C. albicans (22.0%). Fluconazole susceptibility studies of Candida species allowed us to conclude that the majority of C. albicans islolates are susceptible, and that the highest resistance averages were observed in C. glabrata (21.41%) and C. krusei (69.23%).

  12. Uncommon Candida Species Fungemia among Cancer Patients, Houston, Texas, USA.

    PubMed

    Jung, Dong Sik; Farmakiotis, Dimitrios; Jiang, Ying; Tarrand, Jeffrey J; Kontoyiannis, Dimitrios P

    2015-11-01

    Many uncommon Candida species that cause bloodstream infections (BSIs) are not well-characterized. We investigated the epidemiology, antifungal use, susceptibility patterns, and factors associated with all-cause death among cancer patients in whom uncommon Candida spp. BSIs were diagnosed at a cancer treatment center during January 1998–September 2013. Of 1,395 Candida bloodstream isolates, 79 from 68 patients were uncommon Candida spp. The incidence density of uncommon Candida spp. BSIs and their proportion to all candidemia episodes substantively increased during the study period, and the rise was associated with increasing use of echinocandin antifungal drugs. Thirty-seven patients had breakthrough infections during therapy or prophylaxis with various systemic antifungal drugs for >7 consecutive days; 21 were receiving an echinocandin. C. kefyr (82%), and C. lusitaniae (21%) isolates frequently showed caspofungin MICs above the epidemiologic cutoff values. These findings support the need for institutional surveillance for uncommon Candida spp. among cancer patients.

  13. In vitro pharmacodynamic modelling of anidulafungin against Candida spp.

    PubMed

    Gil-Alonso, Sandra; Jauregizar, Nerea; Ortega, Ignacio; Eraso, Elena; Suárez, Elena; Quindós, Guillermo

    2016-03-01

    The aim of this study was to fit anidulafungin in vitro static time-kill data from nine strains of Candida with a pharmacodynamic (PD) model in order to describe the antifungal activity of this drug against Candida spp. Time-kill data from strains of Candida albicans, Candida glabrata and Candida parapsilosis clades were best fit using an adapted sigmoidal Emax model and resulted in a set of PD parameters (Emax, EC50 and Hill factor) for each fungal strain. The data were analysed with NONMEM 7. Anidulafungin was effective in a species- and concentration-dependent manner against the strains of C. glabrata and C. parapsilosis clades as observed with the EC50 estimates. Maximum killing rate constant (Emax) values were higher against C. glabrata and C. parapsilosis complex strains. In conclusion, we demonstrated that the activity of anidulafungin against Candida can be accurately described using an adapted sigmoidal Emax model.

  14. Screening of Tanzanian medicinal plants for anti-Candida activity

    PubMed Central

    Runyoro, Deborah KB; Matee, Mecky IN; Ngassapa, Olipa D; Joseph, Cosam C; Mbwambo, Zakaria H

    2006-01-01

    Background Candida albicans has become resistant to the already limited, toxic and expensive anti-Candida agents available in the market. These factors necessitate the search for new anti-fungal agents. Methods Sixty-three plant extracts, from 56 Tanzanian plant species obtained through the literature and interviews with traditional healers, were evaluated for anti-Candida activity. Aqueous methanolic extracts were screened for anti-Candida activity by bioautography agar overlay method, using a standard strain of Candida albicans (ATCC 90028). Results Twenty- seven (48%) out of the 56 plants were found to be active. Extracts of the root barks of Albizia anthelmintica and Balanites aegyptiaca, and roots of Plectranthus barbatus showed strong activity. Conclusion The extracts that showed strong anti-Candida activity are worth of further investigation in order to isolate and identify the active compounds. PMID:16571139

  15. Identification and characterization of nine atypical Candida dubliniensis clinical isolates.

    PubMed

    Albaina, Olatz; Sahand, Ismail H; Brusca, María I; Sullivan, Derek J; Fernández de Larrinoa, Iñigo; Moragues, María D

    2015-02-01

    Candida dubliniensis is a pathogenic yeast of the genus Candida closely related to Candida albicans. The phenotypic similarity of these two species often leads to misidentification of C. dubliniensis isolates in clinical samples. DNA-based methods continue to be the most effective means of discriminating accurately between the two species. Here, we report on the identification of nine unusual Candida isolates that showed ambiguous identification patterns on the basis of their phenotypic and immunological traits. The isolates were categorized into two groups. Group I isolates were unable to produce germ tubes and chlamydospores, and to agglutinate commercial latex particles coated with a mAb highly specific for C. dubliniensis. Group II isolates grew as pink and white colonies on CHROMagar Candida and ChromID Candida, respectively. Carbohydrate assimilation profiles obtained with API/ID32C together with PCR amplification with specific primers and DNA sequencing allowed reliable identification of the nine unusual clinical isolates as C. dubliniensis.

  16. 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.

  17. Candida Biofilms: Development, Architecture, and Resistance.

    PubMed

    Chandra, Jyotsna; Mukherjee, Pranab K

    2015-08-01

    Intravascular device-related infections are often associated with biofilms (microbial communities encased within a polysaccharide-rich extracellular matrix) formed by pathogens on the surfaces of these devices. Candida species are the most common fungi isolated from catheter-, denture-, and voice prosthesis-associated infections and also are commonly isolated from contact lens-related infections (e.g., fungal keratitis). These biofilms exhibit decreased susceptibility to most antimicrobial agents, which contributes to the persistence of infection. Recent technological advances have facilitated the development of novel approaches to investigate the formation of biofilms and identify specific markers for biofilms. These studies have provided extensive knowledge of the effect of different variables, including growth time, nutrients, and physiological conditions, on biofilm formation, morphology, and architecture. In this article, we will focus on fungal biofilms (mainly Candida biofilms) and provide an update on the development, architecture, and resistance mechanisms of biofilms.

  18. Adaptive immune responses to Candida albicans infection

    PubMed Central

    Richardson, Jonathan P; Moyes, David L

    2015-01-01

    Fungal infections are becoming increasingly prevalent in the human population and contribute to morbidity and mortality in healthy and immunocompromised individuals respectively. Candida albicans is the most commonly encountered fungal pathogen of humans, and is frequently found on the mucosal surfaces of the body. Host defense against C. albicans is dependent upon a finely tuned implementation of innate and adaptive immune responses, enabling the host to neutralise the invading fungus. Central to this protection are the adaptive Th1 and Th17 cellular responses, which are considered paramount to successful immune defense against C. albicans infections, and enable tissue homeostasis to be maintained in the presence of colonising fungi. This review will highlight the recent advances in our understanding of adaptive immunity to Candida albicans infections. PMID:25607781

  19. Candida Biofilms: Development, Architecture, and Resistance

    PubMed Central

    CHANDRA, JYOTSNA; MUKHERJEE, PRANAB K.

    2015-01-01

    Intravascular device–related infections are often associated with biofilms (microbial communities encased within a polysaccharide-rich extracellular matrix) formed by pathogens on the surfaces of these devices. Candida species are the most common fungi isolated from catheter-, denture-, and voice prosthesis–associated infections and also are commonly isolated from contact lens–related infections (e.g., fungal keratitis). These biofilms exhibit decreased susceptibility to most antimicrobial agents, which contributes to the persistence of infection. Recent technological advances have facilitated the development of novel approaches to investigate the formation of biofilms and identify specific markers for biofilms. These studies have provided extensive knowledge of the effect of different variables, including growth time, nutrients, and physiological conditions, on biofilm formation, morphology, and architecture. In this article, we will focus on fungal biofilms (mainly Candida biofilms) and provide an update on the development, architecture, and resistance mechanisms of biofilms. PMID:26350306

  20. Candida bracarensis Detected Among Isolates of Candida glabrata by Petide Nucleic Acid Fluorescence in Situ Hybirdization: Susceptibility Data and Documentation of Presumed Infection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Molecular taxonomic studies have revealed new yeast (Candida) species among phenotypically-delineated species: the best example being Candida dubliniensis. This study was designed to determine the occurrence of two new molecularly-defined species, Candida bracarensis and Candida nivariensis, which ...

  1. Genetic Transformation of Candida glabrata by Electroporation

    PubMed Central

    Tscherner, Michael; Kuchler, Karl

    2016-01-01

    Here, we report a method for the transformation by electroporation of the human fungal pathogen Candida glabrata (C. glabrata). The protocol can be used for transformations in single well or in 96-well microtiter plates. It has been extensively used to generate a genome-scale gene deletion library using the C. glabrata background recipient strain ATCC2001 (Schwarzmüller et al., 2014). PMID:27774499

  2. Characterization of Mucosal Candida albicans Biofilms

    PubMed Central

    Dongari-Bagtzoglou, Anna; Kashleva, Helena; Dwivedi, Prabhat; Diaz, Patricia; Vasilakos, John

    2009-01-01

    C. albicans triggers recurrent infections of the alimentary tract mucosa that result from biofilm growth. Although the ability of C. albicans to form a biofilm on abiotic surfaces has been well documented in recent years, no information exists on biofilms that form directly on mucosal surfaces. The objectives of this study were to characterize the structure and composition of Candida biofilms forming on the oral mucosa. We found that oral Candida biofilms consist of yeast, hyphae, and commensal bacteria, with keratin dispersed in the intercellular spaces. Neutrophils migrate through the oral mucosa and form nests within the biofilm mass. The cell wall polysaccharide β-glucan is exposed during mucosal biofilm growth and is more uniformly present on the surface of biofilm organisms invading the oral mucosa. We conclude that C. albicans forms complex mucosal biofilms consisting of both commensal bacterial flora and host components. These discoveries are important since they can prompt a shift of focus for current research in investigating the role of Candida-bacterial interactions in the pathogenesis of mucosal infections as well as the role of β-glucan mediated signaling in the host response. PMID:19956771

  3. 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.

  4. 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

  5. Production and function of cytokines in natural and acquired immunity to Candida albicans infection.

    PubMed Central

    Ashman, R B; Papadimitriou, J M

    1995-01-01

    Host resistance against infections caused by the yeast Candida albicans is mediated predominantly by polymorphonuclear leukocytes and macrophages. Antigens of Candida stimulate lymphocyte proliferation and cytokine synthesis, and in both humans and mice, these cytokines enhance the candidacidal functions of the phagocytic cells. In systemic candidiasis in mice, cytokine production has been found to be a function of the CD4+ T helper (Th) cells. The Th1 subset of these cells, characterized by the production of gamma interferon and interleukin-2, is associated with macrophage activation and enhanced resistance against reinfection, whereas the Th2 subset, which produces interleukins-4, -6, and -10, is linked to the development of chronic disease. However, other models have generated divergent data. Mucosal infection generally elicits Th1-type cytokine responses and protection from systemic challenge, and identification of cytokine mRNA present in infected tissues of mice that develop mild or severe lesions does not show pure Th1- or Th2-type responses. Furthermore, antigens of C. albicans, mannan in particular, can induce suppressor cells that modulate both specific and nonspecific cellular and humoral immune responses, and there is an emerging body of evidence that molecular mimicry may affect the efficiency of anti-Candida responses within defined genetic contexts. PMID:8531890

  6. Postantifungal Effect of Micafungin against the Species Complexes of Candida albicans and Candida parapsilosis.

    PubMed

    Gil-Alonso, Sandra; Jauregizar, Nerea; Eraso, Elena; Quindós, Guillermo

    2015-01-01

    Micafungin is an effective antifungal agent useful for the therapy of invasive candidiasis. Candida albicans is the most common cause of invasive candidiasis; however, infections due to non-C. albicans species, such as Candida parapsilosis, are rising. Killing and postantifungal effects (PAFE) are important factors in both dose interval choice and infection outcome. The aim of this study was to determinate the micafungin PAFE against 7 C. albicans strains, 5 Candida dubliniensis, 2 Candida Africana, 3 C. parapsilosis, 2 Candida metapsilosis and 2 Candida orthopsilosis. For PAFE studies, cells were exposed to micafungin for 1 h at concentrations ranging from 0.12 to 8 μg/ml. Time-kill experiments (TK) were conducted at the same concentrations. Samples were removed at each time point (0-48 h) and viable counts determined. Micafungin (2 μg/ml) was fungicidal (≥ 3 log10 reduction) in TK against 5 out of 14 (36%) strains of C. albicans complex. In PAFE experiments, fungicidal endpoint was achieved against 2 out of 14 strains (14%). In TK against C. parapsilosis, 8 μg/ml of micafungin turned out to be fungicidal against 4 out 7 (57%) strains. Conversely, fungicidal endpoint was not achieved in PAFE studies. PAFE results for C. albicans complex (41.83 ± 2.18 h) differed from C. parapsilosis complex (8.07 ± 4.2 h) at the highest tested concentration of micafungin. In conclusion, micafungin showed significant differences in PAFE against C. albicans and C. parapsilosis complexes, being PAFE for the C. albicans complex longer than for the C. parapsilosis complex.

  7. Postantifungal Effect of Micafungin against the Species Complexes of Candida albicans and Candida parapsilosis

    PubMed Central

    Gil-Alonso, Sandra; Jauregizar, Nerea; Eraso, Elena; Quindós, Guillermo

    2015-01-01

    Micafungin is an effective antifungal agent useful for the therapy of invasive candidiasis. Candida albicans is the most common cause of invasive candidiasis; however, infections due to non-C. albicans species, such as Candida parapsilosis, are rising. Killing and postantifungal effects (PAFE) are important factors in both dose interval choice and infection outcome. The aim of this study was to determinate the micafungin PAFE against 7 C. albicans strains, 5 Candida dubliniensis, 2 Candida Africana, 3 C. parapsilosis, 2 Candida metapsilosis and 2 Candida orthopsilosis. For PAFE studies, cells were exposed to micafungin for 1 h at concentrations ranging from 0.12 to 8 μg/ml. Time-kill experiments (TK) were conducted at the same concentrations. Samples were removed at each time point (0-48 h) and viable counts determined. Micafungin (2 μg/ml) was fungicidal (≥ 3 log10 reduction) in TK against 5 out of 14 (36%) strains of C. albicans complex. In PAFE experiments, fungicidal endpoint was achieved against 2 out of 14 strains (14%). In TK against C. parapsilosis, 8 μg/ml of micafungin turned out to be fungicidal against 4 out 7 (57%) strains. Conversely, fungicidal endpoint was not achieved in PAFE studies. PAFE results for C. albicans complex (41.83 ± 2.18 h) differed from C. parapsilosis complex (8.07 ± 4.2 h) at the highest tested concentration of micafungin. In conclusion, micafungin showed significant differences in PAFE against C. albicans and C. parapsilosis complexes, being PAFE for the C. albicans complex longer than for the C. parapsilosis complex. PMID:26168269

  8. First Case Report of Bloodstream Infection Due to a Candida Species Closely Related to the Novel Species Candida pseudorugosa

    PubMed Central

    Córdoba, Susana; Isla, Guillermina; Fernández, Norma; García, Susana; Mazza, Mariana; Murisengo, Omar Alejandro; Vivot, Walter; Szusz, Wanda; Davel, Graciela; Tiraboschi, Iris Nora; Bosco-Borgeat, María Eugenia

    2012-01-01

    Candida pseudorugosa is a novel species closely related to Candida rugosa for which only one case has been reported. We report the first case of a bloodstream infection in humans caused by a Candida sp. closely related to C. pseudorugosa. We contribute evidence to show this organism as a potential human pathogen that may be misidentified by conventional methods, also pointing out its lower sensitivity to azoles and other antifungal agents. PMID:22461681

  9. Non-Candida albicans Candida mediastinitis of odontogenic origin in a diabetic patient.

    PubMed

    Kofteridis, Diamantis P; Mantadakis, Elpis; Karatzanis, Alexander D; Bourolias, Constantinos A; Papazoglou, Georgios; Velegrakis, George A; Samonis, George

    2008-06-01

    Descending mediastinitis occurs as a complication of oropharyngeal or cervical infections and its delayed diagnosis and treatment are associated with high mortality. A rare case of an odontogenic infection in a diabetic patient, complicated by Candida parapsilosis and Candida krusei parapharyngeal space infection, descending mediastinitis and aspiration pneumonia is described. Isolate identification was based on colonial and microscopic morphological characteristics and carbohydrate assimilation test results. The patient was successfully treated with surgical drainage and debridement, broad spectrum antibacterials and liposomal amphotericin B followed by prolonged oral voriconazole therapy.

  10. Use of CHROMagar Candida for the presumptive identification of Candida species directly from clinical specimens in resource-limited settings

    PubMed Central

    Nadeem, Sayyada Ghufrana; Hakim, Shazia Tabassum; Kazmi, Shahana Urooj

    2010-01-01

    Introduction 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. Material and methods 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. Results 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%. Conclusion 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. PMID:21483597

  11. Structure of N-acetyl-[beta]-D-glucosaminidase (GcnA) from the Endocarditis Pathogen Streptococcus gordonii and its Complex with the Mechanism-based Inhibitor NAG-thiazoline

    SciTech Connect

    Langley, David B.; Harty, Derek W.S.; Jacques, Nicholas A.; Hunter, Neil; Guss, J. Mitchell; Collyer, Charles A.

    2008-09-17

    The crystal structure of GcnA, an N-acetyl-{beta}-D-glucosaminidase from Streptococcus gordonii, was solved by multiple wavelength anomalous dispersion phasing using crystals of selenomethionine-substituted protein. GcnA is a homodimer with subunits each comprised of three domains. The structure of the C-terminal {alpha}-helical domain has not been observed previously and forms a large dimerization interface. The fold of the N-terminal domain is observed in all structurally related glycosidases although its function is unknown. The central domain has a canonical ({beta}/{alpha}){sub 8} TIM-barrel fold which harbours the active site. The primary sequence and structure of this central domain identifies the enzyme as a family 20 glycosidase. Key residues implicated in catalysis have different conformations in two different crystal forms, which probably represent active and inactive conformations of the enzyme. The catalytic mechanism for this class of glycoside hydrolase, where the substrate rather than the enzyme provides the cleavage-inducing nucleophile, has been confirmed by the structure of GcnA complexed with a putative reaction intermediate analogue, N-acetyl-{beta}-D-glucosamine-thiazoline. The catalytic mechanism is discussed in light of these and other family 20 structures.

  12. Intestinal Colonization by Candida albicans Alters Inflammatory Responses in Bruton's Tyrosine Kinase-Deficient Mice

    PubMed Central

    Strijbis, Karin; Yilmaz, Ömer H.; Dougan, Stephanie K.; Esteban, Alexandre; Gröne, Andrea; Kumamoto, Carol A.; Ploegh, Hidde L.

    2014-01-01

    The commensal yeast Candida albicans is part of the human intestinal microflora and is considered a “pathobiont”, a resident microbe with pathogenic potential yet harmless under normal conditions. The aim of this study was to investigate the effect of C. albicans on inflammation of the intestinal tract and the role of Bruton's tyrosine kinase (Btk). Btk is an enzyme that modulates downstream signaling of multiple receptors involved in innate and adaptive immunity, including the major anti-fungal receptor Dectin-1. Colitis was induced in wild type and Btk-/- mice by treatment with dextran sodium sulfate (DSS) and the gastrointestinal tract of selected treatment groups were then colonized with C. albicans. Colonization by C. albicans neither dampened nor exacerbated inflammation in wild type mice, but colon length and spleen weight were improved in Btk-deficient mice colonized with C. albicans. Neutrophil infiltration was comparable between wild type and Btk-/- mice, but the knockout mice displayed severely reduced numbers of macrophages in the colon during both DSS and DSS/Candida treatment. Smaller numbers and reduced responsiveness of Btk-/- macrophages might partially explain the improved colon length of Btk-/- mice as a result of Candida colonization. Surprisingly, DSS/Candida-treated Btk-/- animals had higher levels of certain pro-inflammatory cytokines and levels of the anti-inflammatory cytokine TGF-β were reduced compared to wild type. A clustering and correlation analysis showed that for wild type animals, spleen TGF-β and colon IL-10 and for Btk-/- spleen and colon levels of IL-17A best correlated with the inflammatory parameters. We conclude that in Btk-/- immunocompromised animals, colonization of the gastrointestinal tract by the commensal yeast C. albicans alters inflammatory symptoms associated with colitis. PMID:25379804

  13. Use of CHROMagar Candida medium for isolation of yeasts from dental samples.

    PubMed Central

    Beighton, D; Ludford, R; Clark, D T; Brailsford, S R; Pankhurst, C L; Tinsley, G F; Fiske, J; Lewis, D; Daly, B; Khalifa, N

    1995-01-01

    A new differential medium, CHROMagar Candida, for the isolation of clinically important yeasts was investigated to determine its usefulness in facilitating the study of oral yeasts. The recovery of yeasts on the medium was not significantly different from the recovery on Sabouraud dextrose agar. The identities of 450 green colonies on CHROMagar Candida, presumptively identified as Candida albicans on the basis of the manufacturer's instructions, were confirmed by testing for beta-N-acetylgalactosaminidase. Candida tropicalis also formed distinctive colonies, and other yeasts including Candida (Torulopsis) glabrata, Candida Parapsilosis, Candida Magnoliae, Candida lusitaniae, Candida Famata, Candida kefir, and Saccharomyces cerevisiae were readily distinguished from C. albicans and C. tropicalis isolates. CHROMagar Candida is a very useful medium, and its use will facilitate the study of yeasts associated with dental diseases. PMID:8576366

  14. Candida species biofilm and Candida albicans ALS3 polymorphisms in clinical isolates.

    PubMed

    Bruder-Nascimento, Ariane; Camargo, Carlos Henrique; Mondelli, Alessandro Lia; Sugizaki, Maria Fátima; Sadatsune, Terue; Bagagli, Eduardo

    2014-01-01

    Over the last decades, there have been important changes in the epidemiology of Candida infections. In recent years, Candida species have emerged as important causes of invasive infections mainly among immunocompromised patients. This study analyzed Candida spp. isolates and compared the frequency and biofilm production of different species among the different sources of isolation: blood, urine, vulvovaginal secretions and peritoneal dialysis fluid. Biofilm production was quantified in 327 Candida isolates obtained from patients attended at a Brazilian tertiary public hospital (Botucatu, Sao Paulo). C. albicans ALS3 gene polymorphism was also evaluated by determining the number of repeated motifs in the central domain. Of the 198 total biofilm-positive isolates, 72 and 126 were considered as low and high biofilm producers, respectively. Biofilm production by C. albicans was significantly lower than that by non-albicans isolates and was most frequently observed in C. tropicalis. Biofilm production was more frequent among bloodstream isolates than other clinical sources, in urine, the isolates displayed a peculiar distribution by presenting two distinct peaks, one containing biofilm-negative isolates and the other containing isolates with intense biofilm production. The numbers of tandem-repeat copies per allele were not associated with biofilm production, suggesting the evolvement of other genetic determinants.

  15. Culture media profoundly affect Candida albicans and Candida tropicalis growth, adhesion and biofilm development

    PubMed Central

    Weerasekera, Manjula M; Wijesinghe, Gayan K; Jayarathna, Thilini A; Gunasekara, Chinthika P; Fernando, Neluka; Kottegoda, Nilwala; Samaranayake, Lakshman P

    2016-01-01

    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. PMID:27706381

  16. Metal ions may suppress or enhance cellular differentiation in Candida albicans and Candida tropicalis biofilms.

    PubMed

    Harrison, Joe J; Ceri, Howard; Yerly, Jerome; Rabiei, Maryam; Hu, Yaoping; Martinuzzi, Robert; Turner, Raymond J

    2007-08-01

    Candida albicans and Candida tropicalis are polymorphic fungi that develop antimicrobial-resistant biofilm communities that are characterized by multiple cell morphotypes. This study investigated cell type interconversion and drug and metal resistance as well as community organization in biofilms of these microorganisms that were exposed to metal ions. To study this, Candida biofilms were grown either in microtiter plates containing gradient arrays of metal ions or in the Calgary Biofilm Device for high-throughput susceptibility testing. Biofilm formation and antifungal resistance were evaluated by viable cell counts, tetrazolium salt reduction, light microscopy, and confocal laser scanning microscopy in conjunction with three-dimensional visualization. We discovered that subinhibitory concentrations of certain metal ions (CrO(4)(2-), Co(2+), Cu(2+), Ag(+), Zn(2+), Cd(2+), Hg(2+), Pb(2+), AsO(2)(-), and SeO(3)(2-)) caused changes in biofilm structure by blocking or eliciting the transition between yeast and hyphal cell types. Four distinct biofilm community structure types were discerned from these data, which were designated "domed," "layer cake," "flat," and "mycelial." This study suggests that Candida biofilm populations may respond to metal ions to form cell-cell and solid-surface-attached assemblages with distinct patterns of cellular differentiation.

  17. Adhesion of different Candida spp. to plastic: XTT formazan determinations.

    PubMed

    Hawser, S

    1996-01-01

    Adhesion of synchronized yeast-phase Candida cells to tissue culture plastic was investigated using the tetrazolium salt, XTT. The procedure permits the direct enumeration of adherent yeasts following the metabolic conversion of the XTT tetrazolium salt, to its reduced formazan form, by mitochondrial dehydrogenases. Using this procedure, the formation of XTT formazan by Candida cells was typically related to the inoculum size. The adhesion of Candida yeast-phase cells from different Candida spp. to plastic was of the following order: C. krusei (n = 5) > C. albicans (n = 10) > C. glabrata (n = 6). Furthermore, preliminary experiments with several other species indicated that C. tropicalis (n = 2) may adhere as well as C. albicans and that one strain each of C. guilliermondii and C. parapsilosis appear to adhere to plastic in a similar fashion to C. glabrata. The data indicate the utility of the XTT tetrazolium based assay in enumerating the adhesion of different Candida spp. to plastic.

  18. Candida glabrata olecranon bursitis treated with bursectomy and intravenous caspofungin.

    PubMed

    Skedros, John G; Keenan, Kendra E; Trachtenberg, Joel D

    2013-01-01

    Orthopedic surgeons are becoming more involved in the care of patients with septic arthritis and bursitis caused by yeast species. This case report involves a middle-aged immunocompromised female who developed a Candida glabrata septic olecranon bursitis that developed after she received a corticosteroid injection in the olecranon bursa for presumed aseptic bursitis. Candida (Torulopsis) glabrata is the second most frequently isolated Candida species from the bloodstream in the United States. Increased use of fluconazole and other azole antifungal agents as a prophylactic treatment for recurrent Candida albicans infections in immunocompromised individuals is one reason why there appears to be increased resistance of C. glabrata and other nonalbicans Candida (NAC) species to fluconazole. In this patient, this infection was treated with surgery (bursectomy) and intravenous caspofungin, an echinocandin. This rare infectious etiology coupled with this intravenous antifungal treatment makes this case novel among cases of olecranon bursitis caused by yeasts.

  19. Candida oesophagitis with hepatitis C virus: an uncommon association.

    PubMed

    Yakoob, Javed; Jafri, Wasim; Hussainy, Akbar S

    2003-06-01

    Candida oesophagitis is an acquired immune deficiency syndrome (AIDS)-defining illness. We report a 28-year-old woman who presented with Candida oesophagitis with underlying chronic hepatitis C. The patient presented with anorexia and weakness and was noted to have raised serum transaminases. Upper-gastrointestinal endoscopy revealed Candida oesophagitis involving the whole oesophagus. Oesophageal biopsy demonstrated changes consistent with Candida oesophagitis. Serology was positive for hepatitis C antibodies, and polymerase chain reaction (PCR) genotyped hepatitis C virus (HCV) as genotype 3. Liver biopsy revealed chronic hepatitis with moderately active portal inflammation. A human immunodeficiency virus (HIV) test was non-reactive for types 1 and 2. The development of Candida oesophagitis in a patient with chronic HCV infection demands prompt consideration of general debility and immunosuppression as effects of HCV that led to an occurrence of opportunistic infection. Evaluation of this case provides insight into various mechanisms of immune suppression associated with HCV infection.

  20. Molecular cloning and characterization of the Candida albicans enolase gene.

    PubMed Central

    Mason, A B; Buckley, H R; Gorman, J A

    1993-01-01

    A DNA clone containing the putative Candida albicans enolase gene (ENO1) was isolated from a genomic DNA library. The sequenced insert contained a continuous open reading frame of 1,320 bp. The predicted 440-amino-acid protein is 78 and 76% identical, respectively, to Saccharomyces cerevisiae enolase proteins 1 and 2. Only one enolase gene could be detected in C. albicans genomic DNA by Southern analysis with a homologous probe. Northern (RNA) analysis detected a single, abundant C. albicans ENO1 transcript of approximately 1,600 nucleotides. When cells were grown on glucose, levels of ENO1 mRNA were markedly increased by comparison with ENO1 mRNA levels in cells grown on ethanol, a gluconeogenic carbon source. In contrast to this glucose-mediated transcriptional induction, the carbon source had no dramatic effect on the levels of enolase protein or enzyme activity in the C. albicans strains tested. These results suggest that posttranscriptional mechanisms are responsible for modulating expression of the C. albicans enolase gene. Images PMID:8478328

  1. The isolation of Candida rugosa and Candida mesorugosa from clinical samples in Ghana.

    PubMed

    Adjapong, Gloria; Bartlett, Michael; Hale, Marie; Garrill, Ashley

    2016-03-01

    Members of the Candida rugosa species complex have been described as emerging fungal pathogens and are responsible for a growing number of Candida infections. In this communication we report the isolation of Candida rugosa and Candida mesorugosa in Ghana. To the best of our knowledge this is the first description of this species complex from a clinical setting in Africa.The isolates were identified on the basis of their rRNA gene internal transcribed spacer (ITS) sequences. For one isolate, obtained from sputum, the sequence grouped well with that of C. rugosa. Two other isolates from urine had sequences that grouped with Candida mesorugosa. Morphologically, C. rugosa formed white, wrinkled, and flat colonies on Sabouraud Dextrose Agar (SDA), whereas C. mesorugosa formed white, smooth colonies. On chromogenic medium, the isolates formed small, dry greenish-blue colonies with a pale or white border, similar to C. albicans. The C. rugosa isolate produced pseudohyphae in human serum and on CMA-Tween 80 agar. In contrast, the C. mesorugosa isolates did not generate pseudohyphae in human serum, but generated a few pseudohyphae with abundant blastoconidia on CMA-Tween 80 agar. Growth was observed at 37 °C and 42 °C but not at 45 °C.The two C. mesorugosa isolates had Minimum Inhibitory Concentrations (MICs) of 6 and 48 μg ml(-1) for fluconazole and are thus resistant. The C. rugosa isolate had an MIC of 24 μg ml(-1), indicative of resistance. All three isolates were susceptible to itraconazole and voriconazole (with respective MICs of < 0.125 μg ml(-1)).

  2. Effect of tyrosol on adhesion of Candida albicans and Candida glabrata to acrylic surfaces.

    PubMed

    Monteiro, Douglas Roberto; Feresin, Leonardo Perina; Arias, Laís Salomão; Barão, Valentim Adelino Ricardo; Barbosa, Debora Barros; Delbem, Alberto Carlos Botazzo

    2015-09-01

    The prevention of adhesion of Candida cells to acrylic surfaces can be regarded as an alternative to prevent denture stomatitis. The use of quorum sensing molecules, such as tyrosol, could potentially interfere with the adhesion process. Therefore, the aim of this study was to assess the effect of tyrosol on adhesion of single and mixed cultures of Candida albicans and Candida glabrata to acrylic resin surfaces. Tyrosol was diluted in each yeast inoculum (10(7) cells/ml in artificial saliva) at 25, 50, 100, and 200 mM. Then, each dilution was added to wells of 24-well plates containing the acrylic specimens, and the plates were incubated at 37°C for 2 h. After, the effect of tyrosol was determined by total biomass quantification, metabolic activity of the cells and colony-forming unit counting. Chlorhexidine gluconate (CHG) was used as a positive control. Data were analyzed using analysis of variance (ANOVA) and the Holm-Sidak post hoc test (α = 0.05). The results of total biomass quantification and metabolic activity revealed that the tyrosol promoted significant reductions (ranging from 22.32 to 86.16%) on single C. albicans and mixed cultures. Moreover, tyrosol at 200 mM and CHG significantly reduced (p < 0.05) the number of adhered cells to the acrylic surface for single and mixed cultures of both species, with reductions ranging from 1.74 to 3.64-log10. In conclusion, tyrosol has an inhibitory effect on Candida adhesion to acrylic resin, and further investigations are warranted to clarify its potential against Candida infections.

  3. Otite externe maligne à Candida Albicans

    PubMed Central

    Elayoubi, Fahd; Lachkar, Azeddine; Aabach, Ahmed; Chouai, Mohamed; Ghailan, Mohamed Rachid

    2016-01-01

    L’otite externe maligne est une ostéomyélite de la base du crane. Le Pseudomonas aeruginosa est le germe le plus incriminé. Cependant l’origine fongique n’est pas rare. Patiente âgée de 80 ans avait présenté une otalgie gauche persistante depuis deux mois malgré un traitement bien conduit. L’examen otologique mettait en évidence des signes inflammatoires au niveau du pavillon, une sténose du conduit avec des granulomes, et otorrhée d’allure purulente. Le scanner montrait un comblement otomastoïdien, un processus inflammatoire extensif des tissus pré et rétro-auriculaire et une lyse du tympanal. Vu l’absence d’amélioration un examen mycologique a été réalisé et qui a révélé la présence de Candida Albicans. Les cas d’otite externe maligne à Candida Albicans sont rarement rapportés. L’origine fongique doit être suspecté devant la négativité des prélèvements bactériologiques et la non amélioration malgré un traitement antibiotique bien conduit, et confirmée par des prélèvements mycologiques parfois multiples. L’otite externe maligne à Candida Albicans est une infection rare potentiellement mortelle. PMID:28154677

  4. Candida albicans commensalism in the gastrointestinal tract.

    PubMed

    Neville, B Anne; d'Enfert, Christophe; Bougnoux, Marie-Elisabeth

    2015-11-01

    Candida albicans is a polymorphic yeast species that often forms part of the commensal gastrointestinal mycobiota of healthy humans. It is also an important opportunistic pathogen. A tripartite interaction involving C. albicans, the resident microbiota and host immunity maintains C. albicans in its commensal form. The influence of each of these factors on C. albicans carriage is considered herein, with particular focus on the mycobiota and the approaches used to study it, models of gastrointestinal colonization by C. albicans, the C. albicans genes and phenotypes that are necessary for commensalism and the host factors that influence C. albicans carriage.

  5. Candida parapsilosis Biofilm Identification by Raman Spectroscopy

    PubMed Central

    Samek, Ota; Mlynariková, Katarina; Bernatová, Silvie; Ježek, Jan; Krzyžánek, Vladislav; Šiler, Martin; Zemánek, Pavel; Růžička, Filip; Holá, Veronika; Mahelová, Martina

    2014-01-01

    Colonies of Candida parapsilosis on culture plates were probed directly in situ using Raman spectroscopy for rapid identification of specific strains separated by a given time intervals (up to months apart). To classify the Raman spectra, data analysis was performed using the approach of principal component analysis (PCA). The analysis of the data sets generated during the scans of individual colonies reveals that despite the inhomogeneity of the biological samples unambiguous associations to individual strains (two biofilm-positive and two biofilm-negative) could be made. PMID:25535081

  6. Candida parapsilosis biofilm identification by Raman spectroscopy.

    PubMed

    Samek, Ota; Mlynariková, Katarina; Bernatová, Silvie; Ježek, Jan; Krzyžánek, Vladislav; Šiler, Martin; Zemánek, Pavel; Růžička, Filip; Holá, Veronika; Mahelová, Martina

    2014-12-22

    Colonies of Candida parapsilosis on culture plates were probed directly in situ using Raman spectroscopy for rapid identification of specific strains separated by a given time intervals (up to months apart). To classify the Raman spectra, data analysis was performed using the approach of principal component analysis (PCA). The analysis of the data sets generated during the scans of individual colonies reveals that despite the inhomogeneity of the biological samples unambiguous associations to individual strains (two biofilm-positive and two biofilm-negative) could be made.

  7. Candida infections in newborns: a review.

    PubMed

    Khoory, B J; Vino, L; Dall'Agnola, A; Fanos, V

    1999-10-01

    Despite adequate treatment, nosocomial fungal infections have become an increasingly important cause of morbidity, extended hospitalization, and mortality in critically ill newborn babies. Furthermore, the high incidence of central nervous system involvement in septic newborns frequently results in serious neurological damage and psychomotorial sequelae. The prevention of fungal colonization in the population at risk, together with prompt diagnosis and treatment, are an efficient combination which lead to a better outcome of neonatal fungal infections. New drugs characterized by great efficacy and tolerance have recently been employed in clinical practice. This article summarizes certain aspects of Candida spp. infections in the neonatal period with regard to multisystemic presentation and involvement.

  8. Adherence and receptor relationships of Candida albicans.

    PubMed Central

    Calderone, R A; Braun, P C

    1991-01-01

    The cell surface of Candida albicans is composed of a variety of polysaccharides such as glucan, chitin, and mannan. The first two components primarily provide structure, while the mannan, often covalently linked to protein, constitutes the major antigen of the organism. Mannoproteins also have enzymatic activity (acid protease) and ligand-receptor functions. The complement receptors of C. albicans appear to be mannoproteins that are required for the adherence of the organism to endothelial cells. This is certainly true of the CR3-like protein of C. albicans. Proof that the CR3 is the Candida receptor for endothelial cells is derived from two observations. First, mutants lacking CR3 activity are less adherent in vitro and, in fact, less virulent. Second, the ligand recognized by the CR3 receptor (C3bi) as well as anti-CR3 antibodies blocks adherence of the organism to endothelial cells. The CR2 of C. albicans appears to promote the adherence of the organism to plastic substrates. Unlike the CR2 of mammalian cells, the Candida CR2 recognizes ligands containing the RGD sequence of amino acids in addition to the C3d ligand, which does not contain the RGD sequence. There is uncertainty as to whether the Candida CR2 and CR3 are, in fact, different proteins. A mannoprotein has also been described as the adhesin for epithelial cells. In this case, the receptor has a lectinlike activity and recognizes fucose- or glucosamine-containing glycoproteins of epithelial cells, depending on the strain of C. albicans. The oligosaccharide component of the receptor is probably not involved in ligand recognition and may serve to stabilize the receptor. However, the oligosaccharide factor 6 epitope of mannan may also provide adhesin activity in the recognition of epithelial cells. Mannoproteins can be extracted from cells by a number of reagents. Zymolyase, for instance, tends to remove structural mannoproteins, which contain relatively little protein and are linked to glucan. Reagents

  9. Melittin induces apoptotic features in Candida albicans

    SciTech Connect

    Park, Cana; Lee, Dong Gun

    2010-03-26

    Melittin is a well-known antimicrobial peptide with membrane-active mechanisms. In this study, it was found that Melittin exerted its antifungal effect via apoptosis. Candida albicans exposed to Melittin showed the increased reactive oxygen species (ROS) production, measured by DHR-123 staining. Fluorescence microscopy staining with FITC-annexin V, TUNEL and DAPI further confirmed diagnostic markers of yeast apoptosis including phosphatidylserine externalization, and DNA and nuclear fragmentation. The current study suggests that Melittin possesses an antifungal effect with another mechanism promoting apoptosis.

  10. Electron Microscopy of Young Candida albicans Chlamydospores

    PubMed Central

    Miller, Sara E.; Spurlock, Ben O.; Michaels, G. E.

    1974-01-01

    One- to three-day-old cultures of Candida albicans bearing chlamydospores were grown and harvested by a special technique, free of agar, and prepared for ultramicrotomy and electron microscopy. These young chlamydospores exhibited a subcellular structure similar to that of the yeast phase, e.g., cytoplasmic membrane, ribosomes, and mitochondria. Other structural characteristics unique to chlamydospores were a very thick, layered cell wall, the outer layer of which was continuous with the outer layer of the suspensor cell wall and was covered by hair-like projections; membrane bound organelles; and large lipoid inclusions. Only young chlamydospores less than 3 to 4 days old exhibited these ultrastructural characteristics. Images PMID:4368664

  11. Endocarditis due to a co-infection of Candida albicans and Candida tropicalis in a drug abuser.

    PubMed

    Fesharaki, Shirinsadat Hashemi; Haghani, Iman; Mousavi, Bita; Kargar, Melika Laal; Boroumand, Mohammadali; Anvari, Maryam Sotoudeh; Abbasi, Kyomars; Meis, Jacques F; Badali, Hamid

    2013-11-01

    In recent decades the incidence of Candida endocarditis has increased dramatically. Despite the application of surgery and antifungal therapy, Candida endocarditis remains a life-threatening infection with significant morbidity and mortality. We report a 37-year-old male drug abuser presenting with high fever, chest pain, loss of appetite and cardiac failure. His echocardiography revealed mobile large tricuspid valve vegetations. Fungal endocarditis was confirmed by culturing of the resected vegetation showing mixed growth of Candida albicans and Candida tropicalis, although three consecutive blood cultures were negative for Candida species. Phenotypic identification was reconfirmed by sequencing of the internal transcribed spacer (ITS rDNA) region. The patient was initially treated with intravenous fluconazole (6 mg kg(-1) per day), followed by 2 weeks of intravenous amphotericin B deoxycholate (1 mg kg(-1) per day). Although MICs were low for both drugs, the patient's antifungal therapy combined with valve replacement failed, and he died due to respiratory failure.

  12. Caspofungin MIC Distribution amongst Commonly Isolated Candida Species in a Tertiary Care Centre - An Indian Experience

    PubMed Central

    Gupta, Rajarshi; Mehta, Preeti

    2016-01-01

    Introduction Emergence of Candida species resistant to Amphotericin B and triazole has led to use of echinocandins, mostly caspofungin in the management of invasive candidiasis. There are some published reports of caspofungin resistance in Candida species yet no studies on caspofungin susceptibility pattern of Candida species exist in Indian setup. Aim To carry out the antifungal susceptibility of Candida isolates against caspofungin. Materials and Methods In a retrospective study at a tertiary care teaching hospital, 60 preserved Candida isolates from inpatients of invasive candidiasis obtained over a period of 6 months from January 2015 to June 2015 were subjected to antifungal susceptibility to caspofungin and the Minimum Inhibitory Concentrations (MICs) of Candida species to caspofungin were determined by Epsilometer test (E-test). Results Thirty Candida albicans and 30 Non albicans Candida mainly Candida glabrata, Candida parapsilosis and Candida tropicalis were tested for caspofungin susceptibitity by E-test. Caspofungin resistance was detected in 6.67% Candida albicans isolates. Caspofungin resistance was not observed in Candida parapsilosis, Candida glabrata and Candida tropicalis. This shows that caspofungin resistance is still rare. Further elaborate studies with clinical correlation data are needed to detect prevalence of caspofungin resistance. Conclusion Emergence of resistance in our study warrants need of elaborate studies with clinical correlation data to detect prevalence of resistance to caspofungin. E-test method proved to be an easy and simple technique for testing susceptibility of Candida to caspofungin. PMID:28050365

  13. Evaluation of the New Chromogenic Medium Candida ID 2 for Isolation and Identification of Candida albicans and Other Medically Important Candida Species

    PubMed Central

    Eraso, Elena; Moragues, María D.; Villar-Vidal, María; Sahand, Ismail H.; González-Gómez, Nagore; Pontón, José; Quindós, Guillermo

    2006-01-01

    The usefulness of Candida ID 2 (CAID2) reformulated medium (bioMérieux, France) has been compared with that of the former Candida ID (CAID; bioMérieux), Albicans ID 2 (ALB2; bioMérieux), and CHROMagar Candida (CAC; Chromagar, France) chromogenic media for the isolation and presumptive identification of clinically relevant yeasts. Three hundred forty-five stock strains from culture collections, and 103 fresh isolates from different clinical specimens were evaluated. CAID2 permitted differentiation based on colony color between Candida albicans (cobalt blue; sensitivity, 91.7%; specificity, 97.2%) and Candida dubliniensis (turquoise blue; sensitivity, 97.9%; specificity, 96.6%). Candida tropicalis gave distinguishable pink-bluish colonies in 97.4% of the strains in CAID2 (sensitivity, 97.4%; specificity, 100%); the same proportion was reached in CAC, where colonies were blue-gray (sensitivity, 97.4%; specificity, 98.7%). CAC and CAID2 showed 100% sensitivity values for the identification of Candida krusei. However, with CAID2, experience is required to differentiate the downy aspect of the white colonies of C. krusei from other white-colony-forming species. The new CAID2 medium is a good candidate to replace CAID and ALB2, and it compares well to CAC for culture and presumptive identification of clinically relevant Candida species. CAID2 showed better results than CAC in some aspects, such as quicker growth and color development of colonies from clinical specimens, detection of mixed cultures, and presumptive differentiation between C. albicans and C. dubliniensis. PMID:16954270

  14. Evaluation of the new chromogenic medium Candida ID 2 for isolation and identification of Candida albicans and other medically important Candida species.

    PubMed

    Eraso, Elena; Moragues, María D; Villar-Vidal, María; Sahand, Ismail H; González-Gómez, Nagore; Pontón, José; Quindós, Guillermo

    2006-09-01

    The usefulness of Candida ID 2 (CAID2) reformulated medium (bioMérieux, France) has been compared with that of the former Candida ID (CAID; bioMérieux), Albicans ID 2 (ALB2; bioMérieux), and CHROMagar Candida (CAC; Chromagar, France) chromogenic media for the isolation and presumptive identification of clinically relevant yeasts. Three hundred forty-five stock strains from culture collections, and 103 fresh isolates from different clinical specimens were evaluated. CAID2 permitted differentiation based on colony color between Candida albicans (cobalt blue; sensitivity, 91.7%; specificity, 97.2%) and Candida dubliniensis (turquoise blue; sensitivity, 97.9%; specificity, 96.6%). Candida tropicalis gave distinguishable pink-bluish colonies in 97.4% of the strains in CAID2 (sensitivity, 97.4%; specificity, 100%); the same proportion was reached in CAC, where colonies were blue-gray (sensitivity, 97.4%; specificity, 98.7%). CAC and CAID2 showed 100% sensitivity values for the identification of Candida krusei. However, with CAID2, experience is required to differentiate the downy aspect of the white colonies of C. krusei from other white-colony-forming species. The new CAID2 medium is a good candidate to replace CAID and ALB2, and it compares well to CAC for culture and presumptive identification of clinically relevant Candida species. CAID2 showed better results than CAC in some aspects, such as quicker growth and color development of colonies from clinical specimens, detection of mixed cultures, and presumptive differentiation between C. albicans and C. dubliniensis.

  15. Routine use of CHROMagar Candida medium for presumptive identification of Candida yeast species and detection of mixed fungal populations.

    PubMed

    Bouchara, Jean-Philippe; Declerck, Philippe; Cimon, Bernard; Planchenault, Claire; de Gentile, Ludovic; Chabasse, Dominique

    1996-02-01

    OBJECTIVE: To assess the value of the new differential culture medium CHROMagar Candida for routine investigation of clinical specimens. METHODS: During a whole year, 6150 clinical samples were plated on CHROMagar Candida medium. After incubation, the green colonies were considered to be Candida albicans. The colonies of other colors were identified using Bichrolatex-krusei, or by their assimilation pattern on ID 32C test strips and their morphology on rice cream-agar-Tween. RESULTS: Among the 6150 clinical samples, 1643 were positive for fungi. Aspergillus fumigatus and Geotrichum sp. were the predominant filamentous fungi isolated. Candida albicans was the most common species isolated (1274 of the positive samples; 77.5%), and Candida glabrata was the second most common yeast isolated (174 positive samples; 10.6%). Other yeast species were detected at lower frequencies, mainly Candida tropicalis (3.8%), Candida krusei (2.7%), Saccharomyces cerevisiae (2.7%) and Candida kefyr (2.3%), and 16 samples revealed a lipophilic species, Malassezia furfur. Mixed fungal populations accounted for 14.7% of the positive samples. Two or more yeast species were detected in 206 of the 242 specimens containing mixed fungal populations, and five yeast species were detected in one sample. Additionally, we did not observe significant differences in the isolation of yeasts or filamentous fungi from the 366 samples simultaneously plated on CHROMagar Candida and Sabouraud dextrose agar. Close agreement between the two culture media was observed for 89.9% of these samples. CONCLUSIONS: CHROMagar Candida medium was shown to be extremely helpful in a routine clinical mycology service, facilitating the detection of mixed cultures of yeasts and allowing direct identification of C. albicans, as well as rapid presumptive identification of the other yeasts: C. glabrata, C. tropicalis, C. krusei and S. cerevisiae. This chromogenic medium thus appears to be suitable as a primary culture medium

  16. Investigation of minor species Candida africana, Candida stellatoidea and Candida dubliniensis in the Candida albicans complex among Yaoundé (Cameroon) HIV-infected patients.

    PubMed

    Ngouana, Thierry K; Krasteva, Donika; Drakulovski, Pascal; Toghueo, Rufin K; Kouanfack, Charles; Ambe, Akaba; Reynes, Jacques; Delaporte, Eric; Boyom, Fabrice F; Mallié, Michèle; Bertout, Sébastien

    2015-01-01

    Minor species of the Candida albicans complex may cause overestimation of the epidemiology of C. albicans, and misidentifications could mask their implication in human pathology. Authors determined the occurrence of minor species of the C. albicans complex (C. africana, C. dubliniensis and C. stellatoidea) among Yaoundé HIV-infected patients, Cameroon. Stool, vaginal discharge, urine and oropharyngeal samples were analysed by mycological diagnosis. Isolates were identified by conventional methods and mass spectrometry (MS; carried out by the matrix-assisted laser desorption-ionisation time-of-flight MS protocol). Candida albicans isolates were thereafter submitted to the PCR amplification of the Hwp1 gene. The susceptibility of isolates to antifungal drugs was tested using the Clinical and Laboratory Standards Institute M27-A3 protocol. From 115 C. albicans obtained isolates, neither C. dubliniensis nor C. stellatoidea was observed; two strains of C. africana (422PV and 448PV) were identified by PCR electrophoretic profiles at 700 bp. These two C. africana strains were vaginal isolates. The isolate 448PV was resistant to ketoconazole at the minimal inhibitory concentration of 2 μg ml(-1), and showed reduced susceptibility to amphotericin B at 1 μg ml(-1). This first report on C. africana occurrence in Cameroon brings clues for the understanding of the global epidemiology of this yeast as well as that of minor species of the C. albicans complex.

  17. Epithelial Cell Innate Response to Candida albicans

    PubMed Central

    Naglik, J.R.; Moyes, D.

    2011-01-01

    With the advent of treatments and diseases such as AIDS resulting in increasing numbers of patients with suppressed immune systems, fungal diseases are an escalating problem. Candida albicans is the most common of these fungal pathogens, causing infections in many of these patients. It is therefore important to understand how immunity to this fungus is regulated and how it might be manipulated. Although work has been done to identify the receptors, fungal moieties, and responses involved in anti-Candida immunity, most studies have investigated interactions with myeloid or lymphoid cells. Given that the first site of contact of C. albicans with its host is the mucosal epithelial surface, recent studies have begun to focus on interactions of C. albicans with this site. The results are startling yet in retrospect obvious, indicating that epithelial cells play an important role in these interactions, initiating responses and even providing a level of protection. These findings have obvious implications, not just for fungal pathogens, but also for identifying how host organisms can distinguish between commensal and pathogenic microbes. This review highlights some of these recent findings and discusses their importance in the wider context of infection and immunity. PMID:21441481

  18. Photodynamic inactivation of oropharyngeal Candida strains.

    PubMed

    Postigo, Agustina; Bulacio, Lucía; Sortino, Maximiliano

    2014-09-25

    Oropharyngeal candidiasis (OPC) is an infection frequent in immunocompromised patients. Photodynamic therapy is an alternative to conventional treatments, based on the utilization of compounds that inhibit or kill microorganisms only under the effect of light, process known as Photodynamic Inactivation (PDI). In the present study, PDI of Candida spp. by the natural product α-terthienyl (α-T) was investigated following the guidelines of CLSI M27-A3, under UV-A light irradiation. The optimal values of two variables, exposure irradiation time (ET) and distance to the irradiation source (DIS) were established by employing Design Expert Software (DES). For this purpose, a panel of Candida strains isolated from OPC (C. albicans, C. tropicalis, C. parapsilosis and C. krusei) was employed and optimal values were 5 min (ET) and between 6.06 and 6.43 cm (DIS) with a desirability factor of 0.989. α-T plus UV-A light in the optimal conditions caused a complete reduction in viable cells in 5 min which was demonstrated by viable cells reduction assays and confocal microscopy after vital staining (propidium iodide/fluorescein diacetate). The germ tube formation of C. albicans was inhibited by α-T at sub-inhibitory concentrations. Results showed that α-T plus UV-A light could constitute an alternative for OPC treatments at the optimal conditions determined here.

  19. Genetic determinants of virulence - Candida parapsilosis.

    PubMed

    Singaravelu, Kumara; Gácser, Attila; Nosanchuk, Joshua D

    2014-01-01

    The global epidemiology of fungal infections is changing. While overall, Candida albicans remains the most common pathogen; several institutions in Europe, Asia and South America have reported the rapid emergence to predominance of Candida parapsilosis. This mini-review examines the impact of gene deletions achieved in C. parapsilosis that have been published to date. The molecular approaches to gene disruption in C. parapsilosis and the molecularly characterized genes to date are reviewed. Similar to C. albicans, factors influencing virulence in C. parapsilosis include adherence, biofilm formation, lipid metabolism, and secretion of hydrolytic enzymes such as lipases, phospholipases and secreted aspartyl proteinases. Development of a targeted gene deletion method has enabled the identification of several unique aspects of C. parapsilosis genes that play a role in host-pathogen interactions - CpLIP1, CpLIP2, SAPP1a, SAPP1b, BCR1, RBT1, CpFAS2, OLE1, FIT-2. 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).

  20. Description of Martiniozyma gen. nov. and transfer of seven Candida species to Saturnispora as new combinations.

    PubMed

    Kurtzman, Cletus P

    2015-10-01

    DNA sequence analysis has shown Candida abiesophila (NRRL Y-11514(T), CBS 5366(T)) and Candida asiatica (NRRL Y-63747(T), CBS 10863(T)) to be members of a small clade that is phylogenetically separate from other yeasts. In view of their isolation from neighboring genera, such as Pichia and Saturnispora, the two anamorphic species are proposed for transfer to Martiniozyma gen. nov. (MycoBank MB 812061) with Martiniozyma abiesophila designated as type species (MycoBank MB 812062). In keeping with the International Code of Nomenclature for algae, fungi, and plants, which specifies that related anamorphic and teleomorphic species can be assigned to the same genus, the following Candida species are transferred to Saturnispora to conform with their phylogenetic placement: Candida diversa (NRRL Y-5713(T)), Candida halmiae (CBS 11009(T)), Candida sanitii (CBS 10864(T)), Candida sekii (CBS 10931(T)), Candida siamensis (CBS 11022(T)), Candida silvae (NRRL Y-6725(T)) and Candida suwanaritii (CBS 11021(T)).

  1. Candida isolates in tertiary hospitals in northeastern Brazil

    PubMed Central

    Hinrichsen, Sylvia Lemos; Falcão, érica; Vilella, Tatiana Aguiar Santos; Rêgo, Leandro; Lira, Conceição; Almeida, Luciano; Martins, Mízia; Araújo, Carmem; Duarte, Marcelo; Lopes, Geraldo

    2009-01-01

    Candida is an opportunistic pathogen that affects high–risk patients who are either immunocompromised or critically ill and is associated with almost 80% of all nosocomial fungal infections, representing the major cause of fungemia with high mortality rates (40%). Candida albicans is the main cause of candidemia and among the non-albicans species C. parapsilosis, C. glabrata and C. tropicalis are the most frequent agents. The aim of this study was to evaluate the distribution of Candida species in two tertiary hospitals in Recife, Northeastern Brazil. It began by surveying all positive Candida cultures processed by the microbiology laboratory from September 2003 to September 2006. The cultures, originated from various types of biological material (blood, urine, tracheal, catheter and others), were processed by Vitec® system (Biomerieux SA, France). A total of 1.279 (hospital A: 837; hospital B: 442) sample isolates were positive for Candida. The most frequent species in both hospitals were: C. albicans (367), C. tropicalis (363), C. parapsilosis (147), C. glabrata (81), C. krusei (30) and C. guillermondii (14). The isolates were obtained from 746 hospitalized patients. A total of 221 positive hemocultures were detected in 166 different patients in both hospitals, and 113 (68.1%) of these patients with positive hemocultures presented Candida in other body sites. This study shows that Candida non-albicans was the main isolated agent and evidences the importante of C. tropicalis in nosocomial fungal infections. PMID:24031366

  2. Prevalence of oral Candida in the first year of life.

    PubMed

    Stecksén-Blicks, C; Granström, E; Silfverdal, S A; West, C E

    2015-09-01

    Colonisation of the gastrointestinal tract is influenced by primary microbial exposure and bioactive factors in breastmilk. The aim was to explore the prevalence of oral Candida in the first year of life in relation to selected exposures. Oral Candida was studied in 100 healthy infants at 4 and 8 weeks, 3, 6 and 12 months of age and related to delivery mode, birth weight, infant health and feeding, antibiotics, antimycotics, steroids and probiotics in mother and infant, living conditions, maternal smoking and infections The association between lactoferrin and antisecretory factor in breastmilk and maternal serum haemoglobin, transferrin, and ferritin levels in relation to oral Candida was also explored. About 11% to 15% of the infants had oral Candida at the respective age. Colonisation was fairly stable until 6 months of age. There was no conclusive impact of the investigated exposures at entry. Infants with a furry pet at home had a lower frequency of Candida at 3 months, (P < 0.05) whereas all but one colonised infant had older siblings at 12 months (P < 0.01). Lactoferrin in breastmilk was negatively associated with colonisation at 6 months of age. It is concluded that 11 to 15% had oral Candida. Exposure to furry pets and siblings impacted oral Candida.

  3. Community lifestyle of Candida in mixed biofilms: a mini review.

    PubMed

    Thein, Z M; Seneviratne, C J; Samaranayake, Y H; Samaranayake, L P

    2009-11-01

    Candida is the most common human fungal pathogen that causes a variety of afflictions from superficial mucosal infections to deep mycoses. Biofilm formation is a major virulence factor of Candida, and more than 300 articles have been published on Candida biofilms over the past two decades. However, most of these data are on monospecies biofilms of Candida, and information on mixed-species Candida biofilms or bacteria-Candida combinations is still scarce. Yet, in nature, the yeast exist in a mixed milieu either in the oral cavity or in other habitats with a multitude of bacteria colonising mucosal surfaces within a shared community. This mini review describes the current knowledge on candidal-candidal or bacterial-candidal interactions in mixed-species biofilms. The underlying mechanisms of these interactions appear to depend on several factors relating to biofilm development, such as species and strains of organisms, nutritional factors, aerobiosis and related environmental factors. Although the fundamental nature of these interactions appears to be commensalism and antagonism, the emerging evidence based on novel molecular, proteomic and imaging tools indicates these biological mechanisms to be far more complex than hitherto recognised. Demystifying the mechanisms underlying the growth and development of mixed-species communities involving Candida will undoubtedly yield useful data for the effective management of microbial infections in general.

  4. Comparison of the clinical risk factors between Candida albicans and Candida non-albicans species for bloodstream infection.

    PubMed

    Shigemura, Katsumi; Osawa, Kayo; Jikimoto, Takumi; Yoshida, Hiroyuki; Hayama, Brian; Ohji, Goh; Iwata, Kentaro; Fujisawa, Masato; Arakawa, Soichi

    2014-04-01

    The purpose of this study is to investigate the risk factors and susceptibilities to antifungal agents of Candida albicans and Candida non-albicans species (spp.) in candidemia cases in Kobe University Hospital. We investigated all consecutive patients with candida bloodstream infection (BSI) from 2008-2013 for whose full data were available for analyses, examining clinical factors such as gender, general complications, postoperative status or susceptibilities to antifungal agents. These factors were also compared between Candida albicans spp. and Candida non-albicans by univariate and multivariate analyses. Univariate analyses showed a significantly higher rate of Candida non-albicans species BSI patients cancer (odds ratio (OR) (95% confidence interval (CI))=2.29 (1.04-5.06) and P=0.040), chemotherapy (OR=4.35 (1.11-17.1) and P=0.035), fluconazole (FLCZ) resistance (OR=77.3 (4.51-1324) and P=0.003), and itraconazole (ITCZ) resistance (OR=15.6 (5.39-45.1) and P<0.001) and lower rate of underlying cardiovascular diseases (OR=0.27 (0.09-0.80) and P=0.018) and postoperative status (OR=0.35 (0.16-0.77) and P=0.035) in than Candida albicans. Multivariate analyses demonstrated that Candida non-albicans spp. had significantly higher rate of chemotherapy (OR=4.44 (1.04-19.0) and P=0.045), FLCZ resistance (OR=5.87 (2.01-17.1) and P=0.001), and ITCZ resistance (OR=18.7(5.77-60.4) and P<0.001) and lower rate of underlying cardiovascular diseases (OR=0.25 (0.08-0.82) and P=0.022) than Candida albicans. In conclusion, this study revealed several risk factors for BSI with Candida albicans (underlying cardiovascular diseases and postoperative status) and Candida non-albicans spp. (cancer and chemotherapy), and demonstrated that Candida non-albicans spp. were more resistant to FLCZ and ITCZ than Candida albicans.

  5. Candida albicans and Candida tropicalis in oral candidosis: quantitative analysis, exoenzyme activity, and antifungal drug sensitivity.

    PubMed

    da Costa, Karen Regina Carim; Ferreira, Joseane Cristina; Komesu, Marilena Chinali; Candido, Regina Celia

    2009-02-01

    Candida albicans and C. tropicalis obtained from whole saliva of patients presenting signs of oral candidosis were assayed for quantification of colony forming units, exoenzyme activity (phospholipase and proteinase) and antifungal drug sensitivity (amphotericin B, fluconazole and itraconazole) by the reference method of the Clinical and Laboratory Standards Institute. The number of colony forming units per milliliter varied according to the Candida species involved and whether a single or mixed infection was present. Proteinase activity was observed in both C. albicans and C. tropicalis, but phospholipase activity was noted only in C. albicans. In vitro resistance to antifungals was verified in both species, but C. tropicalis appears to be more resistant to the tested antifungals than C. albicans.

  6. Candida flosculorum sp. nov. and Candida floris sp. nov., two yeast species associated with tropical flowers.

    PubMed

    Rosa, Carlos A; Pagnocca, Fernando C; Lachance, Marc-André; Ruivo, Carla C C; Medeiros, Adriana O; Pimentel, Mariana R C; Fontenelle, Julio C R; Martins, Rogério P

    2007-12-01

    Two ascomycetous yeast species, Candida flosculorum sp. nov. and Candida floris sp. nov., were isolated from tropical flowers and their associated insects. C. flosculorum was isolated from flower bracts of Heliconia velloziana and Heliconia episcopalis (Heliconiaceae) collected from two Atlantic rain forest sites in Brazil. C. floris was isolated from flowers of Ipomoea sp. (Convolvulaceae) growing on the banks of the river Paraguai in the pantanal ecosystem in Brazil and from an adult of the stingless bee Trigona sp. and a flower of Merremia quinquefolia (Convolvulaceae) in Costa Rica. C. flosculorum belongs to the Metschnikowiaceae clade and C. floris belongs to the Starmerella clade. The type strain of C. flosculorum is UFMG-JL13(T) (=CBS 10566(T)=NRRL Y-48258(T)) and the type strain of C. floris is UWO(PS) 00-226.2(T) (=CBS 10593(T)=NRRL Y-48255(T)).

  7. Pathogenicity mechanisms and host response during oral Candida albicans infections.

    PubMed

    Hebecker, Betty; Naglik, Julian R; Hube, Bernhard; Jacobsen, Ilse D

    2014-07-01

    Oral candidiasis remains one of the most common forms of Candida infections and occurs if the balance between host, Candida and microbiota is disturbed, e.g., by broad spectrum antibiotics or immunosuppression. In recent years, identification of fungal factors contributing to host cell damage and new insights into host defense mechanisms have significantly extended our understanding of the pathogenesis of oral candidiasis. In this review, we will provide an overview of the pathogenicity mechanisms during oral Candida infections and discuss some approaches by which this knowledge could be transferred into therapeutic approaches.

  8. Candida endophthalmitis: an unusual complication of prolonged intravenous access

    PubMed Central

    Vose, M; Beatty, S; Charles, S

    2001-01-01

    A 16 year old boy awaiting a defunctioning colostomy for Crohn's disease complained of reduced vision in his left eye. Four weeks previously candida had been isolated from his central line used for parenteral feeds. Fundal examination of the left eye revealed a macular abscess with a classic "string of pearls" appearance of multiple vitreous abscesses. This was treated with pars plana vitrectomy and intravitreal antifungal therapy. Microbiological studies confirmed a diagnosis of candida endophthalmitis.


Keywords: candida; endophthalmitis; intravitreal PMID:11161082

  9. Susceptibility of Candida albicans and Candida dubliniensis to Photodynamic Therapy Using Four Dyes as the Photosensitizer

    PubMed Central

    Hosseini, Nasim; Yazdanpanah, Samira; Saki, Maryam; Rezazadeh, Fahimeh; Ghapanchi, Janan; Zomorodian, Kamiar

    2016-01-01

    Statement of the Problem: Oral candidiasis is the most common opportunistic infection affecting the human oral cavity. Photodynamic therapy, as one of its proposed treatment modalities, needs a distinct dye for achieving the best effect. Purpose: The purpose of this study was to evaluate photosensitization effects of four distinct dyes on standard suspension of Candida albicans (C. albicans) and Candida dubliniensis (C. dubliniensis) and biofilm of C. albicans considering the obtained optimum dye concentration and duration of laser irradiation. Materials and Method: In this in vitro study, colony forming units (CFU) of two sets of four groups of Laser plus Dye (L+D+), Dye (L-D+), Laser (L+D-) and No Laser, No Dye (L-D-) were assessed individually with different methylene blue concentrations and laser irradiation period. The photodynamic therapy effect on standard suspension of Candida species (using methylene blue, aniline blue, malachite green and crystal violet) were studied based on the obtained results. Similar investigation was performed on biofilm of C. albicans using the spectral absorbance. Data were imported to SPSS and assessed by statistical tests of analysis of variance (ANOVA) and Tukey test (α= 0.05). Results: CFU among the different dye concentration and irradiation time decrease in dose- and time-dependent manner (p> 0.05), all of which were significantly lower than the control groups (p< 0.05). Among the examined photosensitizers, there was no statistically significant difference, (p> 0.05) though all of them were significantly decrease CFU compared with the control groups (p< 0.05). In L+D- and L+D+ groups, biofilm was significantly destroyed more than that of L-D- (p< 0.05). Conclusion: Photodynamic therapy might be used as an effective procedure to treat Candida associated mucocutaneous diseases and killing biofilm in the infected surfaces such as dentures. PMID:27942552

  10. Biofilms of non-Candida albicans Candida species: quantification, structure and matrix composition.

    PubMed

    Silva, Sónia; Henriques, Mariana; Martins, António; Oliveira, Rosário; Williams, David; Azeredo, Joana

    2009-11-01

    Most cases of candidiasis have been attributed to C. albicans, but recently, non- Candida albicans Candida (NCAC) species have been identified as common pathogens. The ability of Candida species to form biofilms has important clinical repercussions due to their increased resistance to antifungal therapy and the ability of yeast cells within the biofilms to withstand host immune defenses. Given this clinical importance of the biofilm growth form, the aim of this study was to characterize biofilms produced by three NCAC species, namely C. parapsilosis, C. tropicalis and C. glabrata. The biofilm forming ability of clinical isolates of C. parapsilosis, C. tropicalis and C. glabrata recovered from different sources, was evaluated by crystal violet staining. The structure and morphological characteristics of the biofilms were also assessed by scanning electron microscopy and the biofilm matrix composition analyzed for protein and carbohydrate content. All NCAC species were able to form biofilms although these were less extensive for C. glabrata compared with C. parapsilosis and C. tropicalis. It was evident that C. parapsilosis biofilm production was highly strain dependent, a feature not evident with C. glabrata and C. tropicalis. Scanning electron microscopy revealed structural differences for biofilms with respect to cell morphology and spatial arrangement. Candida parapsilosis biofilm matrices had large amounts of carbohydrate with less protein. Conversely, matrices extracted from C. tropicalis biofilms had low amounts of carbohydrate and protein. Interestingly, C. glabrata biofilm matrix was high in both protein and carbohydrate content. The present work demonstrates that biofilm forming ability, structure and matrix composition are highly species dependent with additional strain variability occurring with C. parapsilosis.

  11. 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.

  12. Miltefosine inhibits Candida albicans and non-albicans Candida spp. biofilms and impairs the dispersion of infectious cells.

    PubMed

    Vila, Taissa; Ishida, Kelly; Seabra, Sergio Henrique; Rozental, Sonia

    2016-11-01

    Candida spp. can adhere to and form biofilms over different surfaces, becoming less susceptible to antifungal treatment. Resistance of biofilms to antifungal agents is multifactorial and the extracellular matrix (ECM) appears to play an important role. Among the few available antifungals for treatment of candidaemia, only the lipid formulations of amphotericin B (AmB) and the echinocandins are effective against biofilms. Our group has previously demonstrated that miltefosine has an important effect against Candida albicans biofilms. Thus, the aim of this work was to expand the analyses of the in vitro antibiofilm activity of miltefosine to non-albicans Candida spp. Miltefosine had significant antifungal activity against planktonic cells and the development of biofilms of C. albicans, Candida parapsilosis, Candida tropicalis and Candida glabrata. The activity profile in biofilms was superior to fluconazole and was similar to that of AmB and caspofungin. Biofilm-derived cells with their ECM extracted became as susceptible to miltefosine as planktonic cells, confirming the importance of the ECM in the biofilm resistant behaviour. Miltefosine also inhibited biofilm dispersion of cells at the same concentration needed to inhibit planktonic cell growth. The data obtained in this work reinforce the potent inhibitory activity of miltefosine on biofilms of the four most pathogenic Candida spp. and encourage further studies for the utilisation of this drug and/or structural analogues on biofilm-related infections.

  13. 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.

  14. Contribution of Aspartic Proteases in Candida Virulence. Protease Inhibitors against Candida Infections.

    PubMed

    Staniszewska, Monika; Małgorzata, Bondaryk; Zbigniew, Ochal

    2016-08-09

    Candida species are the major opportunistic human pathogens accounting for 70-90% of all invasive fungal infections. Candida spp, especially C. albicans, are able to produce and secrete hydrolytic enzymes, particularly aspartic proteases (Saps). These enzymes production is an evolutionary adaptation of pathogens to utilize nutrients and survive in host. Sap1-10 are believed to contribute to the adhesion and invasion of host tissues through the degradation of cell surface structures. Aspartic proteases control several steps in innate immune evasion and they degrade proteins related to immunological defense (antibodies, complement and cytokines), allowing the fungus to escape from the first line of host defense. The existing ways to identify potential drug targets rely on specific subset like virulence genes, transcriptional and stress response factors. Candida virulence factors like Sap isoenzymes can be pivotal targets for drug development. The identification of mechanism of a non-canonical inflammasome exerted by Saps could open novel therapeutic strategies to dampen hyperinflammatory response in candidiasis.

  15. Candida parapsilosis, an Emerging Fungal Pathogen

    PubMed Central

    Trofa, David; Gácser, Attila; Nosanchuk, Joshua D.

    2008-01-01

    Summary: Candida parapsilosis is an emerging major human pathogen that has dramatically increased in significance and prevalence over the past 2 decades, such that C. parapsilosis is now one of the leading causes of invasive candidal disease. Individuals at the highest risk for severe infection include neonates and patients in intensive care units. C. parapsilosis infections are especially associated with hyperalimentation solutions, prosthetic devices, and indwelling catheters, as well as the nosocomial spread of disease through the hands of health care workers. Factors involved in disease pathogenesis include the secretion of hydrolytic enzymes, adhesion to prosthetics, and biofilm formation. New molecular genetic tools are providing additional and much-needed information regarding C. parapsilosis virulence. The emerging information will provide a deeper understanding of C. parapsilosis pathogenesis and facilitate the development of new therapeutic approaches for treating C. parapsilosis infections. PMID:18854483

  16. Mucosal Immunity and Candida albicans Infection

    PubMed Central

    Moyes, David L.; Naglik, Julian R.

    2011-01-01

    Interactions between mucosal surfaces and microbial microbiota are key to host defense, health, and disease. These surfaces are exposed to high numbers of microbes and must be capable of distinguishing between those that are beneficial or avirulent and those that will invade and cause disease. Our understanding of the mechanisms involved in these discriminatory processes has recently begun to expand as new studies bring to light the importance of epithelial cells and novel immune cell subsets such as Th17 T cells in these processes. Elucidating how these mechanisms function will improve our understanding of many diverse diseases and improve our ability to treat patients suffering from these conditions. In our voyage to discover these mechanisms, mucosal interactions with opportunistic commensal organisms such as the fungus Candida albicans provide insights that are invaluable. Here, we review current knowledge of the interactions between C. albicans and epithelial surfaces and how this may shape our understanding of microbial-mucosal interactions. PMID:21776285

  17. Candida--agent of the diaper dermatitis?

    PubMed

    Dorko, E; Virágová, S; Pilipcinec, E; Tkáciková, L

    2003-01-01

    Occurrence of Candida spp. was determined in a population of 60 infants, 1-15-month-old, with diaper dermatitis, admitted to a neonatal intensive care unit in Hospital Saca (Kosice, Slovakia). Specimens were obtained from the perianal, pubic, inguinal, or gluteal areas that showed signs of secondary infection as manifested by erythema, oozing, vesiculopustular lesions, and pus formation. The most frequently isolated species was C. albicans (41), followed by C. parapsilosis (8), C. tropicalis (4), C. pulcherrima (4), C. guilliermondii (2), and C. zeylanoides (1). Other organisms present in the mixed culture from the diaper area were Staphylococcus aureus (6), Escherichia coli (3), and 2 strains of each group B and D streptococci, and Proteus mirabilis. Infants diapered exclusively in disposable diapers showed less rash than those diapered exclusively or sometimes in cloth diapers.

  18. CHROMagar Candida, a new differential isolation medium for presumptive identification of clinically important Candida species.

    PubMed Central

    Odds, F C; Bernaerts, R

    1994-01-01

    CHROMagar Candida is a novel, differential culture medium that is claimed to facilitate the isolation and presumptive identification of some clinically important yeast species. We evaluated the use of this medium with 726 yeast isolates, including 82 isolated directly on the medium from clinical material. After 2 days of incubation at 37 degrees C, 285 C. albicans isolates gave distinctive green colonies that were not seen with any of 441 other yeast isolates representing 21 different species. A total of 54 C. tropicalis isolates also developed distinctive dark blue-gray colonies with a halo of dark brownish purple in the surrounding agar. C. krusei isolates (n = 43) also formed highly characteristic rough, spreading colonies with pale pink centers and a white edge that was otherwise encountered only rarely with isolates of C. norvegensis. Trichosporon spp. (n = 34) formed small, pale colonies that became larger and characteristically rough with prolonged incubation. Most of the other 310 yeasts studied formed colonies with a color that ranged from white to pink to purple with a brownish tint. The only exceptions were found among isolates identified as Geotrichum sp. or Pichia sp., some of which formed colonies with a gray to blue color and which in two instances formed a green pigment or a dark halo in the agar. The specificity and sensitivity of the new medium for the presumptive identification of C. albicans, C. krusei, and C. tropicalis exceeded 99% for all three species. A blinded reading test involving four personnel and 57 yeast isolates representing nine clinically important species confirmed that colonial appearance after 48 h of incubation on CHROMagar Candida afforded the correct presumptive recognition of C. albicans, C. tropicalis, C, krusei, and Trichosporon spp. None of nine bacterial isolates grew on CHROMagar Candida within 72 h, and bacteria (Escherichia coli) grew from only 4 of 104 vaginal, 100 oral, and 99 anorectal swabs. The new medium

  19. Development of Candida-Specific Real-Time PCR Assays for the Detection and Identification of Eight Medically Important Candida Species.

    PubMed

    Zhang, Jing; Hung, Guo-Chiuan; Nagamine, Kenjiro; Li, Bingjie; Tsai, Shien; Lo, Shyh-Ching

    2016-01-01

    Culture-based identification methods have been the gold standard for the diagnosis of fungal infection. Currently, molecular technologies such as real-time PCR assays with short turnaround time can provide desirable alternatives for the rapid detection of Candida microbes. However, most of the published PCR primer sets are not Candida specific and likely to amplify DNA from common environmental contaminants, such as Aspergillus microbes. In this study, we designed pan-Candida primer sets based on the ribosomal DNA-coding regions conserved within Candida but distinct from those of Aspergillus and Penicillium. We demonstrate that the final two selected pan-Candida primer sets would not amplify Aspergillus DNA and could be used to differentiate eight medically important Candida pathogens in real-time PCR assays based on their melting profiles, with a sensitivity of detection as low as 10 fg of Candida genomic DNA. Moreover, we further evaluated and selected species-specific primer sets covering Candida albicans, Candida glabrata, Candida tropicalis, and Candida dubliniensis and show that they had high sensitivity and specificity. These real-time PCR primer sets could potentially be assembled into a single PCR array for the rapid detection of Candida species in various clinical settings, such as corneal transplantation.

  20. Budding off: bringing functional genomics to Candida albicans.

    PubMed

    Anderson, Matthew Z; Bennett, Richard J

    2016-03-01

    Candida species are the most prevalent human fungal pathogens, with Candida albicans being the most clinically relevant species. Candida albicans resides as a commensal of the human gastrointestinal tract but is a frequent cause of opportunistic mucosal and systemic infections. Investigation of C. albicans virulence has traditionally relied on candidate gene approaches, but recent advances in functional genomics have now facilitated global, unbiased studies of gene function. Such studies include comparative genomics (both between and within Candida species), analysis of total RNA expression, and regulation and delineation of protein-DNA interactions. Additionally, large collections of mutant strains have begun to aid systematic screening of clinically relevant phenotypes. Here, we will highlight the development of functional genomics in C. albicans and discuss the use of these approaches to addressing both commensalism and pathogenesis in this species.

  1. Antifungal Activity of Plant Extracts against Candida Species from Oral Lesions

    PubMed Central

    Prabhakar, K.; Kumar, L. Sathish; Rajendran, S.; Chandrasekaran, M.; Bhaskar, K.; Sajit Khan, A. K.

    2008-01-01

    Seventy five patients with oral lesions attending the different departments of Rajah Muthiah Medical College and Hospital, Annamalai University were screened for Candida. Forty six (61.3%) Candida strains were isolated from the oral lesions. Of the 46 Candida strains, Candida albicans accounted for 35 (76.08%), Candida glabrata for 5 (10.86%), Candida tropicalis and Candida krusei for 2 (4.34%) each and Candida parapsilosis and Candida guilliermondii for one (2.17%) each. Antifungal activity of ethanol extracts of five plant species that included Syzygium jambolanum, Cassia siamea, Odina wodier, Momordica charantia and Melia azedarach and two algal species, Sargassum wightii and Caulerpa scalpelliformis were tested against 25 isolated strains by disc diffusion method. Antifungal activity was observed at 100 mg/ml for Syzygium jambolanum, Cassia siamea and Caulerpa scalpelliformis and at 10 mg/ml for Sargassum wightii. PMID:21369447

  2. Antifungal Activity of Plant Extracts against Candida Species from Oral Lesions.

    PubMed

    Prabhakar, K; Kumar, L Sathish; Rajendran, S; Chandrasekaran, M; Bhaskar, K; Sajit Khan, A K

    2008-11-01

    Seventy five patients with oral lesions attending the different departments of Rajah Muthiah Medical College and Hospital, Annamalai University were screened for Candida. Forty six (61.3%) Candida strains were isolated from the oral lesions. Of the 46 Candida strains, Candida albicans accounted for 35 (76.08%), Candida glabrata for 5 (10.86%), Candida tropicalis and Candida krusei for 2 (4.34%) each and Candida parapsilosis and Candida guilliermondii for one (2.17%) each. Antifungal activity of ethanol extracts of five plant species that included Syzygium jambolanum, Cassia siamea, Odina wodier, Momordica charantia and Melia azedarach and two algal species, Sargassum wightii and Caulerpa scalpelliformis were tested against 25 isolated strains by disc diffusion method. Antifungal activity was observed at 100 mg/ml for Syzygium jambolanum, Cassia siamea and Caulerpa scalpelliformis and at 10 mg/ml for Sargassum wightii.

  3. [Isolation of Candida spp. from ascites in cirrhotic patients].

    PubMed

    Saludes, Paula; Araguás, Cristina; Sánchez-Delgado, Jordi; Dalmau, Blai; Font, Bernat

    2016-10-01

    The isolation of Candida spp. in ascites of cirrhotic patients is an uncommon situation in clinical practice. Factors that have been associated with increased susceptibility to primary fungal peritonitis are exposure to broad-spectrum antibiotics and immunosuppression, a typical situation of these patients. We report seven episodes of Candida spp. isolation in ascites of cirrhotic patients detected in our hospital during the past 15years.

  4. Candida Arthritis: Analysis of 112 Pediatric and Adult Cases

    PubMed Central

    Gamaletsou, Maria N.; Rammaert, Blandine; Bueno, Marimelle A.; Sipsas, Nikolaos V.; Moriyama, Brad; Kontoyiannis, Dimitrios P.; Roilides, Emmanuel; Zeller, Valerie; Taj-Aldeen, Saad J.; Miller, Andy O.; Petraitiene, Ruta; Lortholary, Olivier; Walsh, Thomas J.

    2016-01-01

    Background. Candida arthritis is a debilitating form of deeply invasive candidiasis. However, its epidemiology, clinical manifestations, management, and outcome are not well understood. Methods. Cases of Candida arthritis were reviewed from 1967 through 2014. Variables included Candida spp in joint and/or adjacent bone, underlying conditions, clinical manifestations, inflammatory biomarkers, diagnostic imaging, management, and outcome. Results. Among 112 evaluable cases, 62% were males and 36% were pediatric. Median age was 40 years (range, <1–84 years). Most patients (65%) were not pharmacologically immunosuppressed. Polyarticular infection (≥3 joints) occurred in 31% of cases. Clinical manifestations included pain (82%), edema (71%), limited function (39%), and erythema (22%) with knees (75%) and hips (15%) most commonly infected. Median erythrocyte sedimentation rate was 62 mm/hr (10–141) and C reactive protein 26 mg/dL (0.5–95). Synovial fluid median white blood cell count was 27 500/µL (range, 100–220 000/µL) with 90% polymorphonuclear neutrophils (range, 24–98). Adjacent osteomyelitis was present in 30% of cases. Candida albicans constituted 63%, Candida tropicalis 14%, and Candida parapsilosis 11%. Most cases (66%) arose de novo, whereas 34% emerged during antifungal therapy. Osteolysis occurred in 42%, joint-effusion in 31%, and soft tissue extension in 21%. Amphotericin and fluconazole were the most commonly used agents. Surgical interventions included debridement in 25%, irrigation 10%, and drainage 12%. Complete or partial response was achieved in 96% and relapse in 16%. Conclusion. Candida arthritis mainly emerges as a de novo infection in usually non-immunosuppressed patients with hips and knees being most commonly infected. Localizing symptoms are frequent, and the most common etiologic agents are C albicans, C tropicalis, and C parapsilosis. Management of Candida arthritis remains challenging with a clear risk of relapse

  5. Analysis of gene evolution and metabolic pathways using the Candida Gene Order Browser

    PubMed Central

    2010-01-01

    Background Candida species are the most common cause of opportunistic fungal infection worldwide. Recent sequencing efforts have provided a wealth of Candida genomic data. We have developed the Candida Gene Order Browser (CGOB), an online tool that aids comparative syntenic analyses of Candida species. CGOB incorporates all available Candida clade genome sequences including two Candida albicans isolates (SC5314 and WO-1) and 8 closely related species (Candida dubliniensis, Candida tropicalis, Candida parapsilosis, Lodderomyces elongisporus, Debaryomyces hansenii, Pichia stipitis, Candida guilliermondii and Candida lusitaniae). Saccharomyces cerevisiae is also included as a reference genome. Results CGOB assignments of homology were manually curated based on sequence similarity and synteny. In total CGOB includes 65617 genes arranged into 13625 homology columns. We have also generated improved Candida gene sets by merging/removing partial genes in each genome. Interrogation of CGOB revealed that the majority of tandemly duplicated genes are under strong purifying selection in all Candida species. We identified clusters of adjacent genes involved in the same metabolic pathways (such as catabolism of biotin, galactose and N-acetyl glucosamine) and we showed that some clusters are species or lineage-specific. We also identified one example of intron gain in C. albicans. Conclusions Our analysis provides an important resource that is now available for the Candida community. CGOB is available at http://cgob.ucd.ie. PMID:20459735

  6. Rat Indwelling Urinary Catheter Model of Candida albicans Biofilm Infection

    PubMed Central

    Nett, Jeniel E.; Brooks, Erin G.; Cabezas-Olcoz, Jonathan; Sanchez, Hiram; Zarnowski, Robert; Marchillo, Karen

    2014-01-01

    Indwelling urinary catheters are commonly used in the management of hospitalized patients. Candida can adhere to the device surface and propagate as a biofilm. These Candida biofilm communities differ from free-floating Candida, exhibiting high tolerance to antifungal therapy. The significance of catheter-associated candiduria is often unclear, and treatment may be problematic considering the biofilm drug-resistant phenotype. Here we describe a rodent model for the study of urinary catheter-associated Candida albicans biofilm infection that mimics this common process in patients. In the setting of a functioning, indwelling urinary catheter in a rat, Candida proliferated as a biofilm on the device surface. Characteristic biofilm architecture was observed, including adherent, filamentous cells embedded in an extracellular matrix. Similar to what occurs in human patients, animals with this infection developed candiduria and pyuria. Infection progressed to cystitis, and a biofilmlike covering was observed over the bladder surface. Furthermore, large numbers of C. albicans cells were dispersed into the urine from either the catheter or bladder wall biofilm over the infection period. We successfully utilized the model to test the efficacy of antifungals, analyze transcriptional patterns, and examine the phenotype of a genetic mutant. The model should be useful for future investigations involving the pathogenesis, diagnosis, therapy, prevention, and drug resistance of Candida biofilms in the urinary tract. PMID:25183731

  7. Systemic Candida infection in University hospital 1997-1999: the distribution of Candida biotypes and antifungal susceptibility patterns.

    PubMed

    Ng, K P; Saw, T L; Na, S L; Soo-Hoo, T S

    2001-01-01

    A total of 102 Candida species were isolated from blood cultures from January 1997 to October 1999. Using assimilation of carbohydrate test, 52 (51.0%) of the Candida sp. were identified as C. parapsilosis, 25.5% (26) were C. tropicalis. C. albicans made up 11.8% (12), 6.9% (7) were C. rugosa, 3.8% (4) C. glabrata and 1% (1) C. guilliermondii. No C. dubliniensis was found in the study. In vitro antifungal susceptibility tests showed that all Candida species were sensitive to nystatin, amphotericin B and ketoconazole. Although all isolates remained sensitive to fluconazole, intermediate susceptibility was found in 3 C. rugosa isolates. Antifungal agents with high frequency of resistance were econazole, clotrimazole, miconazole and 5-fluorocytosine. Candida species found to have resistance to these antifungal agents were non-C. albicans.

  8. [Evaluation of a new chromogenic medium (Candida ID) for the isolation and presumptive identification of Candida albicans and other medically important yeasts].

    PubMed

    Quindós, G; Alonso-Vargas, R; Helou, S; Arechavala, A; Martín-Mazuelos, E; Negroni, R

    2001-03-01

    Candidiasis is a frequent human infection caused mainly by Candida albicans. However, other species are emerging as important pathogens, as Candida glabrata, Candida parapsilosis, Candida tropicalis, Candida krusei or Candida guilliermondii. Rapid identification of clinical isolates could facilitate diagnosis and treatment. Candida ID (bioMerieux, Spain) is a new medium for the isolation and presumptive identification of yeasts: C. albicans grows as blue colonies, and C. tropicalis, C. guilliermondii, Candida kefyr and Candida lusitaniae as pink ones. The utility of Candida ID was evaluated with more than 700 clinical isolates and type culture collection strains from different genera including Candida, Cryptococcus, Saccharomyces, and Rhodotorula. Presumptive identification was confirmed by germ tube test, microscopic morphology and chlamydoconidia production on corn meal agar and carbohydrate assimilation on API-ATB ID 32C or Vitek (bioMerieux). Growth on Candida ID was rapid (18-24 h) for most of the yeast strains tested. Sensitivity and specificity of identification of C. albicans was significantly high (>98%), since a very low number of isolates were found to be false negative or false positive. A better result was obtained for species growing as pink colonies (>99.5%). Detection of different species of medical important yeasts was easy with Candida ID, as perfectly distinct colors and textures of colonies were observed on this medium. Candida ID allowed the discrimination between C. glabrata (creamy and smooth) and C. krusei (rough and white) colonies. Other species showed different colony textures and colours, white being the predominant colour. Candida ID was very useful for the presumptive identification C. albicans isolates.

  9. Comparison of the in vitro activity of echinocandins against Candida albicans, Candida dubliniensis, and Candida africana by time-kill curves.

    PubMed

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

    2015-05-01

    Candida albicans remains the most common fungal pathogen. This species is closely related to 2 phenotypically similar cryptic species, Candida dubliniensis and Candida africana. This study aims to compare the antifungal activities of echinocandins against 7 C. albicans, 5 C. dubliniensis, and 2 C. africana strains by time-kill methodology. MIC values were similar for the 3 species; however, differences in killing activity were observed among species, isolates, and echinocandins. Echinocandins produced weak killing activity against the 3 species. In all drugs, the fungicidal endpoint (99.9% mortality) was reached at ≤31 h with ≥0.5 μg/mL for anidulafungin in 4 C. albicans and 1 C. dubliniensis, for caspofungin in 1 C. albicans and 2 C. dubliniensis, and for micafungin in 4 C. albicans and 1 C. dubliniensis. None of echinocandins showed lethality against C. africana. Identification of these new cryptic species and time-kill studies would be recommendable when echinocandin treatment fails.

  10. 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

  11. New pharmacological properties of Medicago sativa and Saponaria officinalis saponin-rich fractions addressed to Candida albicans.

    PubMed

    Sadowska, Beata; Budzyńska, Aleksandra; Więckowska-Szakiel, Marzena; Paszkiewicz, Małgorzata; Stochmal, Anna; Moniuszko-Szajwaj, Barbara; Kowalczyk, Mariusz; Różalska, Barbara

    2014-08-01

    The antifungal activity of the saponin-rich fractions (SFs) from Medicago sativa (aerial parts and roots) and Saponaria officinalis (used as a well-known source of plant saponins) against Candida albicans reference and clinical strains, their yeast-to-hyphal conversion, adhesion, and biofilm formation was investigated. Direct fungicidal/fungistatic properties of the tested phytochemicals used alone, as well as their synergy with azoles (probably resulting from yeast cell wall instability) were demonstrated. Here, to the best of our knowledge, we report for the first time the ability of saponin-rich extracts of M. sativa and S. officinalis to inhibit C. albicans germ tube formation, limit hyphal growth, reduce yeast adherence and biofilm formation, and eradicate mature (24 h) Candida biofilm. Moreover, M. sativa SFs (mainly obtained from aerial parts), in the range of concentrations which were active modulators of Candida virulence factors, exhibited low cytotoxicity against the mouse fibroblast line L929. These properties seem to be very promising in the context of using plant-derived SFs as potential novel antifungal therapeutics supporting classic drugs or as ingredients of disinfectants.

  12. Sphingolipids Mediate Differential Echinocandin Susceptibility in Candida albicans and Aspergillus nidulans

    PubMed Central

    Healey, Kelley R.; Challa, Krishna K.; Edlind, Thomas D.

    2015-01-01

    The cell wall synthesis-inhibiting echinocandins, including caspofungin and micafungin, play important roles in the treatment of candidiasis and aspergillosis. Previous studies revealed that, in the haploid yeast Candida glabrata, sphingolipid biosynthesis pathway mutations confer caspofungin reduced susceptibility (CRS) but micafungin increased susceptibility (MIS). Here, we describe one Candida albicans strain (of 10 tested) that similarly yields CRS-MIS mutants at relatively high frequency. Mutants demonstrated increased levels of long-chain bases (sphingolipid pathway intermediates) and, unique to this strain, loss of His104/Pro104 heterozygosity in the TSC13-encoded enoyl reductase. CRS-MIS was similarly observed in a C. albicans homozygous fen1Δ fen12Δ laboratory strain and in diverse wild-type strains following exogenous long-chain-base treatment. Analogous to these results, CRS-MIS was demonstrated in an Aspergillus nidulans basA mutant encoding defective sphingolipid C4-hydroxylase and in its wild-type parent exposed to long-chain bases. Sphingolipids likely modulate echinocandin interaction with their Fks membrane target in all susceptible fungi, with potential implications for optimizing therapy with existing antifungals and the development of novel agents. PMID:25824222

  13. Candida albicans stimulates Streptococcus mutans microcolony development via cross-kingdom biofilm-derived metabolites

    PubMed Central

    Kim, Dongyeop; Sengupta, Arjun; Niepa, Tagbo H. R.; Lee, Byung-Hoo; Weljie, Aalim; Freitas-Blanco, Veronica S.; Murata, Ramiro M.; Stebe, Kathleen J.; Lee, Daeyeon; Koo, Hyun

    2017-01-01

    Candida albicans is frequently detected with heavy infection of Streptococcus mutans in plaque-biofilms from children affected with early-childhood caries, a prevalent and costly oral disease. The presence of C. albicans enhances S. mutans growth within biofilms, yet the chemical interactions associated with bacterial accumulation remain unclear. Thus, this study was conducted to investigate how microbial products from this cross-kingdom association modulate S. mutans build-up in biofilms. Our data revealed that bacterial-fungal derived conditioned medium (BF-CM) significantly increased the growth of S. mutans and altered biofilm 3D-architecture in a dose-dependent manner, resulting in enlarged and densely packed bacterial cell-clusters (microcolonies). Intriguingly, BF-CM induced S. mutans gtfBC expression (responsible for Gtf exoenzymes production), enhancing Gtf activity essential for microcolony development. Using a recently developed nanoculture system, the data demonstrated simultaneous microcolony growth and gtfB activation in situ by BF-CM. Further metabolites/chromatographic analyses of BF-CM revealed elevated amounts of formate and the presence of Candida-derived farnesol, which is commonly known to exhibit antibacterial activity. Unexpectedly, at the levels detected (25–50 μM), farnesol enhanced S. mutans-biofilm cell growth, microcolony development, and Gtf activity akin to BF-CM bioactivity. Altogether, the data provide new insights on how extracellular microbial products from cross-kingdom interactions stimulate the accumulation of a bacterial pathogen within biofilms. PMID:28134351

  14. Quantitation of Candida CFU in initial positive blood cultures.

    PubMed

    Pfeiffer, Christopher D; Samsa, Gregory P; Schell, Wiley A; Reller, L Barth; Perfect, John R; Alexander, Barbara D

    2011-08-01

    One potential limitation of DNA-based molecular diagnostic tests for Candida bloodstream infection (BSI) is organism burden, which is not sufficiently characterized. We hypothesized that the number of CFU per milliliter (CFU/ml) present in an episode of Candida BSI is too low for reliable DNA-based diagnostics. In this study, we determined Candida burden in the first positive blood culture and explored factors that affect organism numbers and patient outcomes. We reviewed records of consecutive patients with a positive blood culture for Candida in the lysis-centrifugation blood culture system (Isolator, Wampole Laboratories, Cranbury, NJ) from 1987 to 1991. Descriptive statistics and logistic regression analyses were performed. One hundred fifty-two episodes of Candida BSI were analyzed. Patient characteristics included adult age (72%), indwelling central venous catheters (83%), recent surgery (29%), neutropenia (24%), transplant (14%), and other immune suppression (21%). Rates of treatment success and 30-day mortality for candidemia were each 51%. The median CFU/ml was 1 (mode 0.1, range 0.1 to >1,000). In the multivariate analysis, pediatric patients were more likely than adults to have high organism burdens (odds ratio [OR], 10.7; 95% confidence interval [95% CI], 4.3 to 26.5). Initial organism density did not affect patient outcome. Candida CFU/ml in the first positive blood culture of a BSI episode varies greatly; >50% of cultures had ≤1 CFU/ml, a concentration below the experimental yeast cell threshold for reliable DNA-based diagnostics. DNA-based diagnostics for Candida BSI will be challenged by low organism density and the need for sufficient specimen volume; future research on alternate targets is warranted.

  15. Assimilation of NAD(+) precursors in Candida glabrata.

    PubMed

    Ma, Biao; Pan, Shih-Jung; Zupancic, Margaret L; Cormack, Brendan P

    2007-10-01

    The yeast pathogen Candida glabrata is a nicotinamide adenine dinucleotide (NAD(+)) auxotroph and its growth depends on the environmental supply of vitamin precursors of NAD(+). C. glabrata salvage pathways defined in this article allow NAD(+) to be synthesized from three compounds - nicotinic acid (NA), nicotinamide (NAM) and nicotinamide riboside (NR). NA is salvaged through a functional Preiss-Handler pathway. NAM is first converted to NA by nicotinamidase and then salvaged by the Preiss-Handler pathway. Salvage of NR in C. glabrata occurs via two routes. The first, in which NR is phosphorylated by the NR kinase Nrk1, is independent of the Preiss-Handler pathway. The second is a novel pathway in which NR is degraded by the nucleosidases Pnp1 and Urh1, with a minor role for Meu1, and ultimately converted to NAD(+) via the nicotinamidase Pnc1 and the Preiss-Handler pathway. Using C. glabrata mutants whose growth depends exclusively on the external NA or NR supply, we also show that C. glabrata utilizes NR and to a lesser extent NA as NAD(+) sources during disseminated infection.

  16. Effect of Tetrandrine against Candida albicans Biofilms

    PubMed Central

    Zhao, Lan-Xue; Li, De-Dong; Hu, Dan-Dan; Hu, Gan-Hai; Yan, Lan; Wang, Yan; Jiang, Yuan-Ying

    2013-01-01

    Candida albicans is the most common human fungal pathogen and has a high propensity to develop biofilms that are resistant to traditional antifungal agents. In this study, we investigated the effect of tetrandrine (TET) on growth, biofilm formation and yeast-to-hypha transition of C. albicans. We characterized the inhibitory effect of TET on hyphal growth and addressed its possible mechanism of action. Treatment of TET at a low concentration without affecting fungal growth inhibited hyphal growth in both liquid and solid Spider media. Real-time RT-PCR revealed that TET down-regulated the expression of hypha-specific genes ECE1, ALS3 and HWP1, and abrogated the induction of EFG1 and RAS1, regulators of hyphal growth. Addition of cAMP restored the normal phenotype of the SC5314 strain. These results indicate that TET may inhibit hyphal growth through the Ras1p-cAMP-PKA pathway. In vivo, at a range of concentrations from 4 mg/L to 32 mg/L, TET prolonged the survival of C. albicans-infected Caenorhabditis elegans significantly. This study provides useful information for the development of new strategies to reduce the incidence of C. albicans biofilm-associated infections. PMID:24260276

  17. Vaginal Candida parapsilosis: pathogen or bystander?

    PubMed Central

    Nyirjesy, Paul; Alexander, Alynn B; Weitz, M Velma

    2005-01-01

    OBJECTIVE: Candida parapsilosis is an infrequent isolate on vaginal cultures; its role as a vaginal pathogen remains unstudied. This retrospective study of women with positive culture for C. parapsilosis sought to characterize the significance of this finding and its response to antifungal therapy. METHODS: From February 2001 to August 2002, we identified all individuals with positive fungal isolates among a population of women with chronic vulvovaginal symptoms. Charts of women with C. parapsilosis cultures were reviewed with regard to patient demographics, clinical presentation and therapeutic response. Mycological cure, defined as a negative fungal culture at the next office visit, and clinical cure, i.e. symptom resolution, were determined for each subject. RESULTS: A total of 582 women had positive vaginal cultures for 635 isolates, of which 54 (8.5%) were C. parapsilosis. The charts of 51 subjects with C. parapsilosis were available for review and follow-up cultures and clinical information were available for 39 (76.5%). Microscopy was positive in 9 (17.6%). Antifungal treatment resulted in mycological cure in 17/19 patients with fluconazole, 7/7 with butoconazole, 6/6 with boric acid, 1/1 with miconazole and occurred spontaneously in 6/7: 24/37 (64.9%) patients with a mycological cure experienced clinical cure. CONCLUSIONS: Although C. parapsilosis is often a cause of vaginal symptoms, it seems to respond to a variety of antifungal agents and may even be a transient vaginal colonizer. PMID:16040326

  18. High-frequency switching in Candida albicans.

    PubMed Central

    Soll, D R

    1992-01-01

    Most strains of Candida albicans are capable of switching frequently and reversibly between a number of phenotypes distinguishable by colony morphology. A number of different switching systems have been defined according to the limited set of phenotypes in each switching repertoire, and each strain appears to possess a single system. Switching can affect many aspects of cellular physiology and morphology and appears to be a second level of phenotypic variability superimposed upon the bud-hypha transition. The most dramatic switching system so far identified is the "white-opaque transition." This system dramatizes the extraordinary effects switching can have on the budding cell phenotype, including the synthesis of opaque-specific antigens, the expression of white-specific and opaque-specific genes, and the genesis of unique cell wall structures. Switching has been demonstrated to occur at sites of infection and between episodes of recurrent vaginitis, and it may function to generate variability in commensal and infecting populations for adaptive reasons. Although the molecular mechanisms involved in the switch event are not understood, recent approaches to its elucidation are discussed and an epigenetic mechanism is proposed. Images PMID:1576587

  19. Resveratrol lacks antifungal activity against Candida albicans.

    PubMed

    Collado-González, Mar; Guirao-Abad, José P; Sánchez-Fresneda, Ruth; Belchí-Navarro, Sarai; Argüelles, Juan-Carlos

    2012-06-01

    The putative candicidal activity of resveratrol is currently a matter of controversy. Here, the antifungal activity as well as the antioxidant response of resveratrol against Candida albicans, have been tested in a set of strains with a well-established genetic background At the doses usually employed in antifungal tests (10-40 μg/ml), resveratrol has no effect on the exponential growth of the C. albicans CAI.4 strain, a tenfold increase (400 μg/ml) was required in order to record a certain degree of cell killing, which was negligible in comparison with the strong antifungal effect caused by the addition of amphotericin B (5 μg/ml). An identical pattern was recorded in the prototrophic strains of C. albicans SC5314 and RM-100, whereas the oxidative sensitive trehalose-deficient mutant (tps1/tps1 strain) was totally refractory to the presence of resveratrol. In turn, the serum-induced yeast-to-hypha transition remained unaffected upon addition of different concentrations of resveratrol. Determination of endogenous trehalose and catalase activity, two antioxidant markers in C. albicans; revealed no significant changes in their basal contents induced by resveratrol. Collectively, our results seem to dismiss a main antifungal role as well as the therapeutic application of resveratrol against the infections caused by C. albicans.

  20. Candida albicans Biofilms and Human Disease

    PubMed Central

    Nobile, Clarissa J.; Johnson, Alexander D.

    2016-01-01

    In humans, microbial cells (including bacteria, archaea, and fungi) greatly outnumber host cells. Candida albicans is the most prevalent fungal species of the human microbiota; this species asymptomatically colonizes many areas of the body, particularly the gastrointestinal and genitourinary tracts of healthy individuals. Alterations in host immunity, stress, resident microbiota, and other factors can lead to C. albicans overgrowth, causing a wide range of infections, from superficial mucosal to hematogenously disseminated candidiasis. To date, most studies of C. albicans have been carried out in suspension cultures; however, the medical impact of C. albicans (like that of many other microorganisms) depends on its ability to thrive as a biofilm, a closely packed community of cells. Biofilms are notorious for forming on implanted medical devices, including catheters, pacemakers, dentures, and prosthetic joints, which provide a surface and sanctuary for biofilm growth. C. albicans biofilms are intrinsically resistant to conventional antifungal therapeutics, the host immune system, and other environmental perturbations, making biofilm-based infections a significant clinical challenge. Here, we review our current knowledge of biofilms formed by C. albicans and closely related fungal species. PMID:26488273

  1. Miconazole activity against Candida biofilms developed on acrylic discs.

    PubMed

    Gebremedhin, S; Dorocka-Bobkowska, B; Prylinski, M; Konopka, K; Duzgunes, N

    2014-08-01

    Oral candidiasis in the form of Candida-associated denture stomatitis (CaDS) is associated with Candida adhesion and biofilm formation on the fitting surface of poly (methyl methacrylate) (PMMA) dentures. Candida biofilms show considerable resistance to most conventional antifungal agents, a phenomenon that is considered a developmental-phase-specific event that may help explain the high recurrence rates associated with CaDS. The aim of this study was to examine the activity of miconazole towards in vitro-grown mature Candida biofilms formed on heat-cured PMMA discs as a standardized model. The effect of miconazole nitrate on Candida biofilms developed on acrylic discs was determined for C. albicans MYA-2732 (ATCC), C. glabrata MYA-275 (ATCC), and clinical isolates, C. albicans 6122/06, C. glabrata 7531/06, C. tropicalis 8122/06, and C. parapsilosis 11375/07. Candida biofilms were developed on heat-cured poly(methyl methacrylate) discs and treated with miconazole (0.5 - 96 μg/ml). The metabolic activity of the biofilms was measured by the XTT reduction assay. The minimum inhibitory concentrations (MICs) of miconazole against Candida species were determined by the microdilution method. The MICs for miconazole for the investigated strains ranged from 0.016-32 μg/ml. Treatment with miconazole resulted in a significant reduction of biofilm metabolic activity for all strains. The highest inhibition was observed at 96 μg/ml miconazole. In the case of C. glabrata MYA-275 and C. tropicalis 8122/06 this corresponded to 83.7% and 75.4% inhibition, respectively. The lowest reduction was observed for C. parapsilosis 11375/07-46.1%. For all Candida strains there was a strong correlation between MIC values and miconazole concentrations corresponding to a reduction of metabolic activity of the biofilm by 50%. Miconazole exhibits high antifungal activity against Candida biofilms developed on the surface of PMMA discs. The study provides support for the use of miconazole as an

  2. Experimental hematogenous candidiasis caused by Candida krusei and Candida albicans: species differences in pathogenicity.

    PubMed Central

    Anaissie, E; Hachem, R; K-Tin-U, C; Stephens, L C; Bodey, G P

    1993-01-01

    Hematogenous infections caused by Candida krusei have been noted with increasing frequency, particularly in cancer patients receiving prophylaxis with antifungal triazoles. Progress in understanding the pathogenesis of this emerging infection has been limited by the lack of an animal model. We developed a CF1 mouse intravenous inoculation model of candidiasis to evaluate the pathogenicity of C. krusei in normal and immunosuppressed mice and to compare it with that of Candida albicans. Several inocula (10(6) to 10(8) CFU per animal) of two clinical strains of C. krusei and three American Type Culture Collection strains of C. albicans were tested. Groups of 20 mice each were injected with a single intravenous dose of one inoculum. Animals randomized to receive C. krusei were immunosuppressed by intraperitoneal injection of cyclophosphamide or the combination of cyclophosphamide plus cortisone acetate or they did not receive immunosuppressive agents (normal mice). One hundred percent mortality was observed in normal mice injected with 10(6) CFU of C. albicans per mouse compared with no mortality in normal mice that received 10(8) CFU of C. krusei per mouse (P < 0.01). Resistance to C. krusei infection was markedly lowered by immunosuppression, particularly by the combination of cyclophosphamide plus cortisone acetate, with a significantly shorter survival and a higher organ fungal burden in immunosuppressed than in normal animals (P < 0.01). Tissue infection was documented by culture and histopathologic findings in all examined organs. Images PMID:8454330

  3. Antifungal effect of lavender honey against Candida albicans , Candida krusei and Cryptococcus neoformans.

    PubMed

    Estevinho, Maria Leticia; Afonso, Sílvia Esteves; Feás, Xesús

    2011-10-01

    Monofloral lavender honey samples (n = 30), were analyzed to test antifungal effect against Candida albicans, Candida krusei, and Cryptococcus neoformans. The specific growth rates (μ) showed that all the yeast growths were reduced in the presence of honey. The honey concentration (% w/v) that inhibited 10% of the yeasts growth (X min) ranged from 31.0% (C. albicans), 16.8% (C. krusei) and 23.0% (C. neoformans). A synthetic honey solution was also tested to determine antifungal activity attributable to sugars. The presence of synthetic honey in the C. krusei culture medium at concentrations above 58.0% (w/v) was established as X min, while C. albicans and C. neoformans were more resistant, since X min values were not reached over the ranged tested (10-60%, w/v). What the data suggests is that the component in the lavender honey responsible for the observed antifungal in vitro properties is not sugar based. Honey might be tapped as a natural resource to look for new medicines for the treatment of mycotic infections. This could be very useful, onsidering the increasing resistance of antifungals. It should be noticed that this is the first study concerning the effect of lavender honey on the growth of pathogenic yeasts.

  4. Adherence of Candida albicans and Candida parapsilosis to epithelial cells correlates with fungal cell surface carbohydrates.

    PubMed

    Lima-Neto, Reginaldo G; Beltrão, Eduardo I C; Oliveira, Patrícia C; Neves, Rejane P

    2011-01-01

    Many studies have described the adherence of Candida albicans to epithelial cells but little is known about Candida parapsilosis adhesion and its role in host cell surface recognition. This study was designed to evaluate the correlation between the adherence of 20 C. albicans and 12 C. parapsilosis strains to human buccal epithelial cells and the expression of fungal cell surface carbohydrates using lectin histochemistry. Adherence assays were carried out by incubating epithelial cells in yeast suspensions (10(7) cells ml(-1) ) and peroxidase conjugated lectins (Con A, WGA, UEA I and PNA at 25 μg ml(-1) ) were used for lectin histochemistry. The results showed that adherence was overall greater for C. albicans than for C. parapsilosis (P < 0.01) and that the individual strain differences correlated with a high content of cell surface α-l-fucose residues as indicated by the UEA I staining pattern. Based on the saccharide specificity of the lectins used, these results suggest that l-fucose residues on cell surface glycoconjugates may represent recognition molecules for interactions between the yeast strain studied and the host (r = 0.6985, P = 0.0045). In addition, our results indicated the presence of α-d-glucose/α-d-mannose, N-acetyl-D-glucosamine/N-acetylneuraminic acid and D-galactose/N-acetyl-D-galactosamine in fungal cell wall.

  5. 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

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

    PubMed

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

    2016-03-01

    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.

  7. Differentiation of Candida dubliniensis from Candida albicans on rosemary extract agar and oregano extract agar.

    PubMed

    de Loreto, Erico Silva; Pozzatti, Patrícia; Alves Scheid, Liliane; Santurio, Deise; Morais Santurio, Janio; Alves, Sydney Hartz

    2008-01-01

    Candida dubliniensis is a recently described pathogenic species which shares many phenotypic features with Candida albicans and therefore, may be misidentified in microbiological laboratories. Because molecular methods can be onerous and unfeasible in routine mycological laboratories with restricted budgets such as those in developing countries, phenotypic techniques have been encouraged in the development of differential media for the presumptive identification of these species. We examined the colony morphology and chlamydospore production of 30 C. dubliniensis isolates and 100 C. albicans isolates on two new proposed media: rosemary (Rosmarinus officinalis) extract agar (REA) and oregano (Origanum vulgare) extract agar (OEA). These substrates are traditionally used as spices and medicinal herbs. In both of these media, all C. dubliniensis isolates (100%) showed rough colonies with peripheral hyphal fringes and abundant chlamydospores after 24 to 48 hr of incubation at 25 degrees C. In contrast, under the same conditions, all isolates of C. albicans (100%) showed smooth colonies without hyphal fringes or chlamydospores. In conclusion, REA and OEA offer a simple, rapid, and inexpensive screening media for the differentiation of C. albicans and C. dubliniensis.

  8. Conserved and Divergent Roles of Bcr1 and CFEM Proteins in Candida parapsilosis and Candida albicans

    PubMed Central

    Maguire, Sarah L.; Guida, Alessandro; Synnott, John M.; Andes, David R.; Butler, Geraldine

    2011-01-01

    Candida parapsilosis is a pathogenic fungus that is major cause of hospital-acquired infection, predominantly due to growth as biofilms on indwelling medical devices. It is related to Candida albicans, which remains the most common cause of candidiasis disease in humans. The transcription factor Bcr1 is an important regulator of biofilm formation in vitro in both C. parapsilosis and C. albicans. We show here that C. parapsilosis Bcr1 is required for in vivo biofilm development in a rat catheter model, like C. albicans. By comparing the transcription profiles of a bcr1 deletion in both species we found that regulation of expression of the CFEM family is conserved. In C. albicans, three of the five CFEM cell wall proteins (Rbt5, Pga7 and Csa1) are associated with both biofilm formation and acquisition of iron from heme, which is an important virulence characteristic. In C. parapsilosis, the CFEM family has undergone an expansion to 7 members. Expression of three genes (CFEM2, CFEM3, and CFEM6) is dependent on Bcr1, and is induced in low iron conditions. All three are involved in the acquisition of iron from heme. However, deletion of the three CFEM genes has no effect on biofilm formation in C. parapsilosis. Our data suggest that the role of the CFEM family in iron acquisition is conserved between C. albicans and C. parapsilosis, but their role in biofilm formation is not. PMID:22145027

  9. The immune response against Candida spp. and Sporothrix schenckii.

    PubMed

    Martínez-Álvarez, José A; Pérez-García, Luis A; Flores-Carreón, Arturo; Mora-Montes, Héctor M

    2014-01-01

    Candida albicans is the main causative agent of systemic candidiasis, a condition with high mortality rates. The study of the interaction between C. albicans and immune system components has been thoroughly studied and nowadays there is a model for the anti-C. albicans immune response; however, little is known about the sensing of other pathogenic species of the Candida genus. Sporothrix schenckii is the causative agent of sporotrichosis, a subcutaneous mycosis, and thus far there is limited information about its interaction with the immune system. In this paper, we review the most recent information about the immune sensing of species from genus Candida and S. schenckii. Thoroughly searches in scientific journal databases were performed, looking for papers addressing either Candida- or Sporothrix-immune system interactions. There is a significant advance in the knowledge of non-C. albicans species of Candida and Sporothrix immune sensing; however, there are still relevant points to address, such as the specific contribution of pathogen-associated molecular patterns (PAMPs) for sensing by different immune cells and the immune receptors involved in such interactions. 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).

  10. Clinical Appearance of Oral Candida Infection and Therapeutic Strategies

    PubMed Central

    Patil, Shankargouda; Rao, Roopa S.; Majumdar, Barnali; Anil, Sukumaran

    2015-01-01

    Candida species present both as commensals and opportunistic pathogens of the oral cavity. For decades, it has enthralled the clinicians to investigate its pathogenicity and to improvise newer therapeutic regimens based on the updated molecular research. Candida is readily isolated from the oral cavity, but simple carriage does not predictably result in development of an infection. Whether it remains as a commensal, or transmutes into a pathogen, is usually determined by pre-existing or associated variations in the host immune system. The candida infections may range from non-life threatening superficial mucocutaneous disorders to invasive disseminated disease involving multiple organs. In fact, with the increase in number of AIDS cases, there is a resurgence of less common forms of oral candida infections. The treatment after confirmation of the diagnosis should include recognizing and eliminating the underlying causes such as ill-fitting oral appliances, history of medications (antibiotics, corticosteroids, etc.), immunological and endocrine disorders, nutritional deficiency states and prolonged hospitalization. Treatment with appropriate topical antifungal agents such as amphotericin, nystatin, or miconazole usually resolves the symptoms of superficial infection. Occasionally, administration of systemic antifungal agents may be necessary in immunocompromised patients, the selection of which should be based upon history of recent azole exposure, a history of intolerance to an antifungal agent, the dominant Candida species and current susceptibility data. PMID:26733948

  11. Pathogenic factors in Candida biofilm-related infectious diseases.

    PubMed

    Hirota, K; Yumoto, H; Sapaar, B; Matsuo, T; Ichikawa, T; Miyake, Y

    2017-02-01

    Candida albicans is a commonly found member of the human microflora and is a major human opportunistic fungal pathogen. A perturbation of the microbiome can lead to infectious diseases caused by various micro-organisms, including C. albicans. Moreover, the interactions between C. albicans and bacteria are considered to play critical roles in human health. The major biological feature of C. albicans, which impacts human health, resides in its ability to form biofilms. In particular, the extracellular matrix (ECM) of Candida biofilm plays a multifaceted role and therefore may be considered as a highly attractive target to combat biofilm-related infectious diseases. In addition, extracellular DNA (eDNA) also plays a crucial role in Candida biofilm formation and its structural integrity and induces the morphological transition from yeast to the hyphal growth form during C. albicans biofilm development. This review focuses on pathogenic factors such as eDNA in Candida biofilm formation and its ECM production and provides meaningful information for future studies to develop a novel strategy to battle infectious diseases elicited by Candida-formed biofilm.

  12. Candida spp. in oral cancer and oral precancerous lesions.

    PubMed

    Gall, Francesca; Colella, Giuseppe; Di Onofrio, Valeria; Rossiello, Raffaele; Angelillo, Italo Francesco; Liguori, Giorgio

    2013-07-01

    To assess the presence of Candida spp. in lesions of the oral cavity in a sample of patients with precancer or cancer of the mouth and evaluate the limitations and advantages of microbiological and histological methods, 103 subjects with precancerous or cancerous lesions and not treated were observed between 2007 and 2009. The presence of Candida in the lesions was analyzed by microbiological and histological methods. Cohen's k statistic was used to assess the agreement between culture method and staining techniques. Forty-eight (47%) patients had cancer and 55 (53%) patients had precancerous lesions. Candida spp. were isolated from 31 (30%) patients with cancerous lesions and 33 (32%) with precancerous lesions. C. albicans was the most frequent species isolated in the lesions. The k value showed a fair overall agreement for comparisons between culture method and PAS (0.2825) or GMS (0.3112). This study supports the frequent presence of Candida spp. in cancer and precancerous lesions of the oral cavity. Both microbiological investigations and histological techniques were reliable for detection of Candida spp. It would be desirable for the two techniques to be considered complementary in the detection of yeast infections in these types of lesions.

  13. In vitro effectiveness of anidulafungin against Candida sp. biofilms.

    PubMed

    Rosato, Antonio; Piarulli, Monica; Schiavone, Brigida Pia Immacolata; Catalano, Alessia; Carocci, Alessia; Carrieri, Antonio; Carone, Addolorata; Caggiano, Giuseppina; Franchini, Carlo; Corbo, Filomena; Montagna, Maria Teresa

    2013-12-01

    This study furnishes deeper insights to previous works on anidulafungin, demonstrating the potent activity against Candida strains planktonic cells and biofilms. Candida sp., associated with many biomaterial-related infections, give rise to infective pathologies typically associated with biofilm formation. We recently determined the in vitro antifungal activities of echinocandin anidulafungin in association with some antifungal drugs against some Candida strains in their planktonic states. A total of 11 Candida strains biofilms were tested in this study: six Candida albicans, three C. parapsilosis and two C. tropicalis. All yeast isolates and ATCC strains were stored at -20°C in glycerol stocks and were subcultured on antimicrobial agent-free Sabouraud dextrose agar plates. MIC endpoints were determined colorimetrically by using the indicator 2,3-bis(2-methoxy-4-nitro-5-sulphophenyl)-5-[(phenylamino)carbonyl]-2H-tetrazolium hydroxide (XTT) with menadione as electron-coupling agent. The activity of anidulafungin was assessed using in vitro microbiological model relevant for clinical practice. Anidulafungin showed a strong activity in vitro against both planktonic and biofilms cells, and our study confirms that high anidulafungin concentrations might establish paradoxical growth effect in C. albicans and C. tropicalis biofilms.

  14. DNA methylation regulates phenotype-dependent transcriptional activity in Candida albicans

    PubMed Central

    Mishra, Prashant K.; Baum, Mary; Carbon, John

    2011-01-01

    DNA methylation is a common epigenetic signaling mechanism associated with silencing of repeated DNA and transcriptional regulation in eukaryotes. Here we report that DNA methylation in the human fungal pathogen Candida albicans is primarily localized within structural genes and modulates transcriptional activity. Major repeat sequences and multigene families are largely free of DNA methylation. Among the genes subject to DNA methylation are those associated with dimorphic transition between yeast and hyphal forms, switching between white and opaque cells, and iron metabolism. Transcriptionally repressed methylated loci showed increased frequency of C-to-T transitions during asexual growth, an evolutionarily stable pattern of repression associated mutation that could bring about genetic alterations under changing environmental or host conditions. Dynamic differential DNA methylation of structural genes may be one factor contributing to morphological plasticity that is cued by nutrition and host interaction. PMID:21730141

  15. Effect of lipolytic activity of Candida adriatica, Candida diddensiae and Yamadazyma terventina on the acidity of extra-virgin olive oil with a different polyphenol and water content.

    PubMed

    Ciafardini, G; Zullo, B A

    2015-05-01

    Previous microbiological research demonstrated the presence of a rich micro-flora composed mainly of yeasts in the suspended fraction of freshly produced olive oil. Some of the yeasts are considered harmful as they can damage the quality of the olive oil through the hydrolysis of the triacylglycerols. Present research has demonstrated that the lipolytic activity of some lipase-producer strains belonging to a yeast species called Candida adriatica, Candida diddensiae and Yamadazyma terventina can be modulated by the water and the polyphenol content of olive oil. Laboratory tests highlighted a substantial increase in free fatty acid in the inoculated olive oil characterized by high water content and low polyphenol concentration. The acidity of the olive oil samples containing 0.06% and 0.31% of water increased significantly by 33% in the lipase-producer yeast strains tested during a period of 2 weeks of incubation at 30 °C. All other yeasts showed strong lipolytic activity in the presence of 1.31% of water - the only exception to this was the C. adriatica 1985 strain. The phenolic compounds typical of olive oil represent another important factor able to condition the viability and the lipolytic activity of the lipase-producer yeasts. From the tests performed on the olive oil characterized by an increasing content of total polyphenols equal to 84, 150 and 510 mg per kg of oil, the percentage of the lipase-producer yeasts able to hydrolyse the triacylglycerols was respectively 100%, 67% and 11%.

  16. In Vitro Antifungal Susceptibility of Oral Candida Isolates from Patients Suffering from Caries and Chronic Periodontitis.

    PubMed

    De-la-Torre, Janire; Ortiz-Samperio, María Esther; Marcos-Arias, Cristina; Marichalar-Mendia, Xabier; Eraso, Elena; Echebarria-Goicouria, María Ángeles; Aguirre-Urizar, José Manuel; Quindós, Guillermo

    2017-01-25

    Caries and chronic periodontitis are common oral diseases where a higher Candida colonization is reported. Antifungal agents could be adjuvant drugs for the therapy of both clinical conditions. The aim of the current study has been to evaluate the in vitro activities of conventional and new antifungal drugs against oral Candida isolates from patients suffering from caries and/or chronic periodontitis. In vitro activities of amphotericin B, fluconazole, itraconazole, miconazole, nystatin, posaconazole and voriconazole against 126 oral Candida isolates (75 Candida albicans, 18 Candida parapsilosis, 11 Candida dubliniensis, six Candida guilliermondii, five Candida lipolytica, five Candida glabrata, four Candida tropicalis and two Candida krusei) from 61 patients were tested by the CLSI M27-A3 method. Most antifungal drugs were highly active, and resistance was observed in less than 5% of tested isolates. Miconazole was the most active antifungal drug, being more than 98% of isolates susceptible. Fluconazole, itraconazole, and the new triazoles, posaconazole and voriconazole, were also very active. Miconazole, fluconazole and voriconazole have excellent in vitro activities against all Candida isolates and could represent suitable treatment for a hypothetically adjunctive therapy of caries and chronic periodontitis.

  17. Gastrointestinal Colonization by Candida albicans Mutant Strains in Antibiotic-Treated Mice

    PubMed Central

    Wiesner, Stephen M.; Jechorek, Robert P.; Garni, Robb M.; Bendel, Catherine M.; Wells, Carol L.

    2001-01-01

    Antibiotic-treated mice orally inoculated with one of three Candida albicans strains (including two mutant strains) or indigenous Candida pelliculosa showed levels of candidal gastrointestinal colonization that were strain specific. However, regardless of strain, the numbers of viable candida were intermediate to high in the stomach, were consistently lowest in the upper small intestine, and increased progressively down the intestinal tract. PMID:11139219

  18. 40 CFR 180.1289 - Candida oleophila Strain O; exemption from the requirement of a tolerance.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Candida oleophila Strain O; exemption... FOOD Exemptions From Tolerances § 180.1289 Candida oleophila Strain O; exemption from the requirement... the microbial pesticide, Candida oleophila Strain O, on apples and pears when applied/used as a...

  19. 40 CFR 180.1289 - Candida oleophila Strain O; exemption from the requirement of a tolerance.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 24 2011-07-01 2011-07-01 false Candida oleophila Strain O; exemption... FOOD Exemptions From Tolerances § 180.1289 Candida oleophila Strain O; exemption from the requirement... the microbial pesticide, Candida oleophila Strain O, on apples and pears when applied/used as a...

  20. Two new anamorphic yeasts, Candida thailandica sp. nov. and Candida lignicola sp. nov., isolated from insect frass in Thailand.

    PubMed

    Jindamorakot, Sasitorn; Limtong, Savitree; Yongmanitchai, Wichien; Tuntirungkij, Manee; Potacharoen, Wanchern; Kawasaki, Hiroko; Nakase, Takashi

    2007-12-01

    Two new yeast strains of the genus Candida were isolated from insect frass collected in Khao-Yai National Park, Nakhonrachasima, Thailand. Based on the morphological, physiological and chemotaxonomic characteristics, and sequence analysis of the D1/D2 domain of 26S rRNA gene, these two strains were found to represent two distinct undescribed species and were named Candida thailandica sp. nov. (ST-17 = BCC 7717(T) = NBRC 102562(T)=CBS 10 610) and Candida lignicola sp. nov. (ST-33 = BCC 7733(T) = NBRC 102564(T) = CBS 10612). In the D1/D2 domain of 26S rRNA gene, C. thailandica (GeneBank accession no. AY228491) differs from Candida tsuchiyae, the nearest species, in 66 nucleotide substitutions (10%) and C. lignicola (GeneBank accession no. AY845350) differs from Candida coipomoensis, the nearest species, in nine nucleotides (1.6%). These two new species are clearly distinguished from their closest species by the assimilation of several carbon compounds.

  1. Efficacy of micafungin in invasive candidiasis caused by common Candida species with special emphasis on non-albicans Candida species.

    PubMed

    Cornely, Oliver A; Vazquez, Jose; De Waele, Jan; Betts, Robert; Rotstein, Coleman; Nucci, Marcio; Pappas, Peter G; Ullmann, Andrew J

    2014-02-01

    The incidence of invasive candidiasis caused by non-albicans Candida (NAC) spp. is increasing. The aim of this analysis was to evaluate the efficacy of micafungin, caspofungin and liposomal amphotericin B in patients with invasive candidiasis and candidaemia caused by different Candida spp. This post hoc analysis used data obtained from two randomised phase III trials was conducted to evaluate the efficacy and safety of micafungin vs. caspofungin and micafungin vs. liposomal amphotericin B. Treatment success, clinical response, mycological response and mortality were evaluated in patients infected with C. albicans and NAC spp. Treatment success rates in patients with either C. albicans or NAC infections were similar. Outcomes were similar for micafungin, caspofungin and liposomal amphotericin B. Candida albicans was the most prevalent pathogen recovered (41.0%), followed by C. tropicalis (17.9%), C. parapsilosis (14.4%), C. glabrata (10.4%), multiple Candida spp. (7.3%) and C. krusei (3.2%). Age, primary diagnosis (i.e. candidaemia or invasive candidiasis), previous corticosteroid therapy and Acute Physiology and Chronic Health Evaluation II score were identified as potential predictors of treatment success and mortality. Micafungin, caspofungin and liposomal amphotericin B exhibit favourable treatment response rates that are comparable for patients infected with different Candida spp.

  2. Effect of trace iron levels and iron withdrawal by chelation on the growth of Candida albicans and Candida vini.

    PubMed

    Holbein, Bruce E; Mira de Orduña, Ramón

    2010-06-01

    The iron requirements of the opportunistic pathogenic yeast, Candida albicans, and the related nonpathogenic spoilage yeast Candida vini were investigated along with their responses to various exogenous iron chelators. The influence of iron as well as the exogenous chelating agents lactoferrin, EDTA, deferiprone, desferrioxamine, bathophenanthroline sulphonate and a novel carried chelator with a hydroxypyridinone-like Fe-ligand functionality, DIBI, on fungal growth was studied in a chemically defined medium deferrated to trace iron levels (<1.2 microg L(-1) or 0.02 microM of Fe). Candida albicans competed better at low iron levels compared with C. vini, which was also more susceptible to most added chelators. Candida albicans was resistant to lactoferrin at physiologically relevant concentrations, but was inhibited by low concentrations of DIBI. Candida vini was sensitive to lactoferrin as well as to DIBI, whose inhibitory activity was shown to be Fe reversible. The pathogenic potential of C. albicans and the nonpathogenic nature of C. vini were consistent with their differing abilities to grow under iron-limiting conditions and in the presence of exogenous iron chelators. Both yeasts could be controlled by appropriately strong chelators. This work provides the first evidence of the iron requirements of the spoilage organism C. vini and its response to exogenous chelators. Efficient iron withdrawal has the potential to provide the basis for new fungal growth control strategies.

  3. Candida biotypes isolated from clinical specimens in Malaysia.

    PubMed

    Ng, K P; Madasamy, M; Saw, T L; Baki, A; He, J; Soo-Hoo, T S

    The distribution of Candida species was examined using 1114 yeasts isolated from various clinical specimens. The isolates were identified by germ tube test, hyphal/pseudohyphae and chlamydoconidia production and carbohydrate assimilation test using ten carbohydrates (glucose, sucrose, trehalose, cellobiose, arabinose, galactose, mannitol, raffinose, lactose and maltose). Among the 1114 isolates studied, 9 species of Candida were identified and the relative frequency of isolation was C. albicans (44.2%), C. parapsilosis (26.0%), C. tropicalis (17.7%), C. glabrata (9.6%), C. krusei (1.2%), C. rugosa (0.6%), C. guilliermondii (0.2%), C. lusitaniae (0.08%) and C. kefyr (0.08%). Non-C. albicans was the most common Candida species isolated from blood, respiratory system, urine and skin. The isolate from vaginal swabs was predominantly C. albicans. 82.2% of C. glabrata and 64.2% of C. krusei isolated in this study were from vaginal swabs.

  4. Phenotypic identification of Candida albicans by growth on chocolate agar.

    PubMed

    Sheth, Chirag C; Johnson, Elizabeth; Baker, Mark E; Haynes, Ken; Mühlschlegel, Fritz A

    2005-12-01

    In this study, we describe a simple method for the identification of Candida albicans in clinical samples. A total of 383 clinical isolates of Candida species were streaked onto chocolate agar and incubated for 48 h at 37 degrees C in the presence of an atmosphere of 6% CO2. All 208 of the C. albicans isolates tested, developed an easy to identify filamentous colony morphology. Of 175 other Candida species tested, 172 (98.3%) were distinguishable from C. albicans by their smooth colony morphology. Three isolates (1.7%) exhibited weak filamentation after prolonged incubation. Although not a routine medium in medical mycology a significant advantage of using chocolate agar lies in its use in clinical bacteriology laboratories for the isolation of fastidious bacteria. Implementation of the proposed method is applicable across a range of specimen types, thus allowing the direct identification of C. albicans in clinical samples. This simple method may allow a quicker entry into directed treatment.

  5. Candida glabrata: new tools and technologies—expanding the toolkit

    PubMed Central

    Ho, Hsueh-lui; Haynes, Ken

    2015-01-01

    In recent years, there has been a noticeable rise in fungal infections related to non-albicans Candida species, including Candida glabrata which has both intrinsic resistance to and commonly acquired resistance to azole antifungals. Phylogenetically, C. glabrata is more closely related to the mostly non-pathogenic model organism Saccharomyces cerevisiae than to other Candida species. Despite C. glabrata's designation as a pathogen by Wickham in 1957, relatively little is known about its mechanism of virulence. Over the past few years, technology to analyse the molecular basis of infection has developed rapidly, and here we briefly review the major advances in tools and technologies available to explore and investigate the virulence of C. glabrata that have occurred over the past decade. PMID:26205243

  6. Direct electrochemical determination of Candida albicans activity.

    PubMed

    Hassan, Rabeay Y A; Bilitewski, Ursula

    2013-11-15

    Despite advances made in the field, rapid detection methods for the human pathogen Candida albicans are still missing. In this regard, bio-electrochemical systems including electrochemical sensors and biosensors satisfy the increasing demand for rapid, reliable, and direct microbial analyses. In this study, the bioelectrochemical characteristics of C. albicans were investigated for use in an analytical system that determines the viability of the organisms. The electrochemical responses of viable and non-viable cells of C. albicans and Saccharomyces cerevisiae were monitored. Cyclic voltammograms (CV) showed an irreversible oxidation peak at about 750 mV that accounts for viable cells. The peak current increased at viable cell numbers ranging from 3 × 10(5) to 1.6 × 10(7)cells/ml, indicating that the amount of viable cells can be accurately quantified. To elucidate the underlying electron transfer processes, the influence of electron transfer chain (ETC) - inhibitors on the electrochemical behavior of the two organisms were investigated. Inhibition of the function of classical respiratory chain (CRC) led to a decrease in the electrochemical response, whereas the oxidation current increased when the alternative oxidase (AOX) pathway was blocked by salicylhydroxamic acid (SHA). Blocking the AOX pathway improved the electrochemical performance, suggesting an involvement in the CRC, with cytochrome c oxidase (COX) as a relevant protein complex. Mutants, in which components of COX were deleted, showed a lower electro-activity than the wild-type strain. Particularly, deletion of subunit COX5a almost completely abolished the electrochemical signal. We believe that this work can be utilized for the development of early detection assays and opens the door for new technological developments in the field of C. albicans.

  7. Diagnosis, management and outcome of Candida endocarditis.

    PubMed

    Lefort, A; Chartier, L; Sendid, B; Wolff, M; Mainardi, J-L; Podglajen, I; Desnos-Ollivier, M; Fontanet, A; Bretagne, S; Lortholary, O

    2012-04-01

    Limited data exist on Candida endocarditis (CE) outcome in the era of new antifungals. As early diagnosis of CE remains difficult, non-culture-based tools need to be evaluated. Through the French prospective MYCENDO study (2005-2007), the overall characteristics and risk factors for death from CE were analysed. The contribution of antigen detection (mannan/anti-mannan antibodies and (1,3)-β-d-glucans) and molecular tools was evaluated. Among 30 CE cases, 19 were caused by non-albicans species. Sixteen patients (53%) had a predisposing cardiac disease, which was a valvular prosthesis in ten (33%). Nine patients (30%) were intravenous drug users; none of them had right-sided CE. Among the 21 patients who were not intravenous drug users, 18 (86%) had healthcare-associated CE. Initial therapy consisted of a combination of antifungals in 12 of 30 patients (40%). Thirteen patients (43%) underwent valve replacement. The median follow-up was 1 year after discharge from hospital (range, 5 months to 4 years) and hospital mortality was 37%. On univariate analysis, patients aged ≥60 years had a higher mortality risk (OR 11, 95% CI 1.2-103.9; p 0.024), whereas intravenous drug use was associated with a lower risk of death (OR 0.12, 95% CI 0.02-0.7; p 0.03). Among 18 patients screened for both serum mannan/anti-mannan antibodies and (1,3)-β-d-glucans, all had a positive result with at least one of either test at CE diagnosis. Real-time PCR was performed on blood (SeptiFast) in 12 of 18, and this confirmed the blood culture results. In conclusion, CE prognosis remains poor, with a better outcome among younger patients and intravenous drug users. Detection of serum antigens and molecular tools may contribute to earlier CE diagnosis.

  8. Echinocandin Resistance in Candida Species Isolates from Liver Transplant Recipients

    PubMed Central

    Prigent, Gwénolé; Aït-Ammar, Nawel; Levesque, Eric; Fekkar, Arnaud; Costa, Jean-Marc; El Anbassi, Sarra; Foulet, Françoise; Duvoux, Christophe; Merle, Jean-Claude

    2016-01-01

    ABSTRACT 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. PMID:27855078

  9. Virulence factors of Candida species isolated from patients with urinary tract infection and obstructive uropathy

    PubMed Central

    Alenzi, Faris Q.B.

    2016-01-01

    Objective: Fungal urinary tract infections due to Candida have increased significantly in recent years. Our research objective was to study Candida species in urine samples of patients with urinary tract infections (UTIs) associated with obstructive uropathy and to investigate the virulence factors of the isolated Candida. Methods: Patients were divided into two groups: Group I (cases): 50 patients with UTIs and obstructive uropathy. Group II (control): 50 patients with UTIs but with no functional or anatomical obstruction of their urinary tract. Clinical histories and physical examinations, together with laboratory investigations of urine samples were carried out in all patients in this study. Mid stream urine samples were examined microscopically and by fungal cell culture. The isolated Candida species were identified by analytical profile index (API). Candida Virulence factors were determined for the isolated Candida. The susceptibility to fluconazole was evaluated. Results: This study revealed an overall isolation rate of 27% of Candida species among all patient groups. The rate was 36% in cases, and 18% in controls, a difference found to be statistically significant (P<0.05). By API, C.albicans was detected in 44% of Candida species in cases, and in 33% in controls. While C.glabrata was detected in 28% of Candida species in cases, and in 22% in controls. C.tropicalis was detected in 17% of Candida species in cases, and in 22% in controls. Both C.krusei and C.kyfr were detected in 5.5% of Candida species in cases, and in 11% in controls. In terms of virulence factors the study showed that 11 out of 27 (40.5%) of Candida isolates were biofilm positive by tube adherence. Phospholipase activity was demonstrated in 12 out of 27 (44.5%) of Candida isolates. Secretory aspartic proteinase activity was demonstrated in 13 out of 27 (48%) of the Candida isolates. Conclusion: Candida is an important cause of UTIs and obstructive uropathy is a major predisposing factor

  10. Candida and candidaemia. Susceptibility and epidemiology.

    PubMed

    Arendrup, Maiken Cavling

    2013-11-01

    In our part of the world invasive fungal infections include invasive yeast infections with Candida as the absolutely dominating pathogen and invasive mould infections with Aspergillus as the main organism. Yeasts are part of our normal micro-flora and invasive infections arise only when barrier leakage or impaired immune function occurs. On the contrary, moulds are ubiquitous in the nature and environment and their conidia inhaled at a daily basis. Hence invasive mould infections typically arise from the airways whereas invasive yeast infections typically enter the bloodstream causing fungaemia. Candida is by far the most common fungal blood stream pathogen; hence this genus has been the main focus of this thesis. As neither the Danish epidemiology nor the susceptibility of fungal pathogens was well described when we initiated our studies we initially wanted to be able to include animal models in our work. Therefore, a comprehensive animal study was undertaken comparing the virulence in a haematogenous mouse model of eight different Candida species including the five most common ones in human infections (C. albicans, C. glabrata, C. krusei, C. parapsilosis and C. tropicalis and in addition three rarer species C. guilliermondii, C. lusitaniae and C. kefyr). We found remarkable differences in the virulence among these species and were able to group the species according to decreasing virulence in three groups I: C. albicans and C. tropicalis, II: C. glabrata, C. lusitaniae and C. kefyr, and III: C. krusei, C. parapsilosis and C. guilliermondii. Apart from being necessary for our subsequent animal experiments exploring in vivo antifungal susceptibility, these findings also helped us understand at least part of the reason for the differences in the epidemiology and the pitfalls associated with the establishment of genus rather than species specific breakpoints. In example, it was less surprising that C. albicans has been the dominant pathogen and associated with a

  11. Influence of glucose concentration on the structure and quantity of biofilms formed by Candida parapsilosis.

    PubMed

    Pereira, Leonel; Silva, Sónia; Ribeiro, Bruno; Henriques, Mariana; Azeredo, Joana

    2015-08-01

    Candida parapsilosis is nowadays an emerging opportunistic pathogen and its increasing incidence is part related to the capacity to produce biofilm. In addition, one of the most important C. parapsilosis pathogenic risk factors includes the organisms' selective growth capabilities in hyperalimentation solutions. Thus, in this study, we investigated the role of glucose in C. parapsilosis biofilm modulation, by studying biofilm formation, matrix composition, and structure. Moreover, the expression of biofilm-related genes (BCR1, FKS1 and OLE1) was analysed in the presence of different glucose percentages. The results demonstrated the importance of glucose in the modulation of C. parapsilosis biofilm. The concentration of glucose had direct implications on the C. parapsilosis transition of yeast cells to pseudohyphae. Additionally, it was demonstrated that biofilm-related genes BCR1, FKS1, and OLE1 are involved in biofilm modulation as a result of glucose. The mechanism by which glucose enhances biofilm formation is not fully understood; however, with this study we were able to demonstrate that C. parapsilosis responds to stress conditions caused by elevated levels of glucose by upregulating genes related to biofilm formation (BCR1, FKS1 and OLE1).

  12. Prospective evaluation of the chromogenic medium CandiSelect 4 for differentiation and presumptive identification of non-Candida albicans Candida species.

    PubMed

    Zhao, Liang; de Hoog, G Sybren; Cornelissen, Akke; Lyu, Qian; Mou, Lili; Liu, Taohua; Cao, Yu; Vatanshenassan, Mansoureh; Kang, Yingqian

    2016-02-01

    Rapid identification of pathogenic yeasts is a crucial step in timely and appropriate antifungal therapy. For diagnostics in the clinical laboratory, simplified alternatives to barcoding are needed. CandiSelect 4 (CS4) medium, a chromogenic medium for isolation of clinical yeasts, allows routine recognition of Candida albicans and presumptive identification of Candida tropicalis, Candida glabrata, and Candida krusei. We evaluated an extension of this method with 46 non-Candida albicans Candida (NCAC) and 7 Malassezia species. The medium supported growth of all species tested and a wide diversity of cultural types were observed. Colony colours were in violet, turquoise (including green and blue), or white tinges. Eight NCAC species produced violet pigmentation similar to that of C. albicans. Most NCAC species, including C. glabrata and C. tropicalis were distributed in the turquoise group. Malassezia species were invariably blue.

  13. Management of Candida biofilms: state of knowledge and new options for prevention and eradication.

    PubMed

    Bujdáková, Helena

    2016-01-01

    Biofilms formed by Candida species (spp.) on medical devices represent a potential health risk. The focus of current research is searching for new options for the treatment and prevention of biofilm-associated infections using different approaches including modern nanotechnology. This review summarizes current information concerning the most relevant resistance/tolerance mechanisms to conventional drugs and a role of additional factors contributing to these phenomena in Candida spp. (mostly Candida albicans). Additionally, it provides an information update in prevention and eradication of a Candida biofilm including experiences with 'lock' therapy, potential utilization of small molecules in biomedical applications, and perspectives of using photodynamic inactivation in the control of a Candida biofilm.

  14. Anticandidal efficacy of cinnamon oil against planktonic and biofilm cultures of Candida parapsilosis and Candida orthopsilosis.

    PubMed

    Pires, Regina Helena; Montanari, Lilian Bueno; Martins, Carlos Henrique G; Zaia, José Eduardo; Almeida, Ana Marisa Fusco; Matsumoto, Marcelo T; Mendes-Giannini, Maria José S

    2011-12-01

    Candida parapsilosis is yeast capable of forming biofilms on medical devices. Novel approaches for the prevention and eradication of the biofilms are desired. This study investigated the anticandidal activity of sixteen essential oils on planktonic and biofilm cultures of C. parapsilosis complex. We used molecular tools, enumeration of colony-forming units, the colourimetric MTT assay, scanning electron microscopy (SEM) and a chequerboard assay coupled with software analyses to evaluate the growth kinetics, architecture, inhibition and reduction in biofilms formed from environmental isolates of the Candida parapsilosis complex; further, we also evaluated whether essential oils would interact synergistically with amphotericin B to increase their anticandidal activities. Of the environmental C. parapsilosis isolates examined, C. parapsilosis and C. orthopsilosis were identified. Biofilm growth on polystyrene substrates peaked within 48 h, after which growth remained relatively stable up to 72 h, when it began to decline. Details of the architectural analysis assessed by SEM showed that C. parapsilosis complex formed less complex biofilms compared with C. albicans biofilms. The most active essential oil was cinnamon oil (CO), which showed anticandidal activity against C. orthopsilosis and C. parapsilosis in both suspension (minimum inhibitory concentration-MIC-250 and 500 μg/ml) and biofilm (minimum biofilm reduction concentration-MBRC-1,000 and 2,000 μg/ml) cultures. CO also inhibited biofilm formation (MBIC) at concentrations above 250 μg/ml for both species tested. However, synergism with amphotericin B was not observed. Thus, CO is a natural anticandidal agent that can be effectively utilised for the control of the yeasts tested.

  15. Enzyme immunoassays for invasive Candida infections: reactivity of somatic antigens of Candida albicans.

    PubMed Central

    Zöller, L; Krämer, I; Kappe, R; Sonntag, H G

    1991-01-01

    The main problem encountered with serodiagnostic tests for Candida infections is their failure to differentiate between invasive and superficial candidosis. Recent immunoblotting studies suggested that the use of selective somatic proteins of Candida albicans as antigens might be a promising approach toward developing a new generation of serodiagnostic assays. In this study major cytoplasmic protein antigens with molecular weights of 47,000 (47K), 46,000 (46K), 45,000 (45K), and 29,000 (29K) were identified as potential marker antigens for antibody detection in invasive candidosis. Continuous-flow isoelectric focusing was employed to enrich the proteins in two fractions, one of them containing the 47K and 29K proteins and the other one containing predominantly the 47K and 45K major proteins. These antigens and a whole somatic antigen extract were used to establish enzyme immunoassays (EIAs) for antibody detection. Whereas all tests were able to discriminate between patients with invasive candidosis (n = 27) and normal healthy volunteers (n = 167), as proved by graphic marker analysis, the selective antigen EIAs were highly superior to the whole somatic antigen EIA and two serological standard assays (indirect immunofluorescence assay and indirect hemagglutination assay) when a panel of sera from patients with superficial candidosis (n = 34) was used as a negative control group. The use of the 47K-29K antigen fraction allowed the best differentiation between invasive and noninvasive candidosis. The corresponding immunoglobulin G class-specific EIA had a sensitivity of 81.5% and a specificity of 97% for both negative control groups as well. Images PMID:1774309

  16. Comparative phenotypic analysis of the major fungal pathogens Candida parapsilosis and Candida albicans.

    PubMed

    Holland, Linda M; Schröder, Markus S; Turner, Siobhán A; Taff, Heather; Andes, David; Grózer, Zsuzsanna; Gácser, Attila; Ames, Lauren; Haynes, Ken; Higgins, Desmond G; Butler, Geraldine

    2014-09-01

    Candida parapsilosis and Candida albicans are human fungal pathogens that belong to the CTG clade in the Saccharomycotina. In contrast to C. albicans, relatively little is known about the virulence properties of C. parapsilosis, a pathogen particularly associated with infections of premature neonates. We describe here the construction of C. parapsilosis strains carrying double allele deletions of 100 transcription factors, protein kinases and species-specific genes. Two independent deletions were constructed for each target gene. Growth in >40 conditions was tested, including carbon source, temperature, and the presence of antifungal drugs. The phenotypes were compared to C. albicans strains with deletions of orthologous transcription factors. We found that many phenotypes are shared between the two species, such as the role of Upc2 as a regulator of azole resistance, and of CAP1 in the oxidative stress response. Others are unique to one species. For example, Cph2 plays a role in the hypoxic response in C. parapsilosis but not in C. albicans. We found extensive divergence between the biofilm regulators of the two species. We identified seven transcription factors and one protein kinase that are required for biofilm development in C. parapsilosis. Only three (Efg1, Bcr1 and Ace2) have similar effects on C. albicans biofilms, whereas Cph2, Czf1, Gzf3 and Ume6 have major roles in C. parapsilosis only. Two transcription factors (Brg1 and Tec1) with well-characterized roles in biofilm formation in C. albicans do not have the same function in C. parapsilosis. We also compared the transcription profile of C. parapsilosis and C. albicans biofilms. Our analysis suggests the processes shared between the two species are predominantly metabolic, and that Cph2 and Bcr1 are major biofilm regulators in C. parapsilosis.

  17. Comparative Phenotypic Analysis of the Major Fungal Pathogens Candida parapsilosis and Candida albicans

    PubMed Central

    Holland, Linda M.; Schröder, Markus S.; Turner, Siobhán A.; Taff, Heather; Andes, David; Grózer, Zsuzsanna; Gácser, Attila; Ames, Lauren; Haynes, Ken; Higgins, Desmond G.; Butler, Geraldine

    2014-01-01

    Candida parapsilosis and Candida albicans are human fungal pathogens that belong to the CTG clade in the Saccharomycotina. In contrast to C. albicans, relatively little is known about the virulence properties of C. parapsilosis, a pathogen particularly associated with infections of premature neonates. We describe here the construction of C. parapsilosis strains carrying double allele deletions of 100 transcription factors, protein kinases and species-specific genes. Two independent deletions were constructed for each target gene. Growth in >40 conditions was tested, including carbon source, temperature, and the presence of antifungal drugs. The phenotypes were compared to C. albicans strains with deletions of orthologous transcription factors. We found that many phenotypes are shared between the two species, such as the role of Upc2 as a regulator of azole resistance, and of CAP1 in the oxidative stress response. Others are unique to one species. For example, Cph2 plays a role in the hypoxic response in C. parapsilosis but not in C. albicans. We found extensive divergence between the biofilm regulators of the two species. We identified seven transcription factors and one protein kinase that are required for biofilm development in C. parapsilosis. Only three (Efg1, Bcr1 and Ace2) have similar effects on C. albicans biofilms, whereas Cph2, Czf1, Gzf3 and Ume6 have major roles in C. parapsilosis only. Two transcription factors (Brg1 and Tec1) with well-characterized roles in biofilm formation in C. albicans do not have the same function in C. parapsilosis. We also compared the transcription profile of C. parapsilosis and C. albicans biofilms. Our analysis suggests the processes shared between the two species are predominantly metabolic, and that Cph2 and Bcr1 are major biofilm regulators in C. parapsilosis. PMID:25233198

  18. Proteolytic activity and cytokine up-regulation by non-albicans Candida albicans.

    PubMed

    Nawaz, Ali; Pärnänen, Pirjo; Kari, Kirsti; Meurman, Jukka H

    2015-05-01

    Mouth is an important source of infections and oral infections such as Candida infections increase the risk of mortality. Our purpose was to investigate differences in proteolytic activity of non-albicans Candida albicans (non-albicans Candida) between clinical isolates and laboratory samples. The second aim was to assess the concentration of pro- and anti-inflammatory cytokine levels IL-1β, IL-10, and TNF-α in saliva of patients with the non-albicans Candida and Candida-negative saliva samples. Clinical yeast samples from our laboratory were used for analyses. Candida strains were grown in YPG at 37 °C for 24 h in water bath with shaking. The activity of Candida proteinases of cell and cell-free fractions were analyzed by MDPF-gelatin zymography. The levels of IL-1β, IL-10, and TNF-α were measured from saliva with ELISA. The study showed differences in the proteolytic activity among the non-albicans Candida strains. C. tropicalis had higher proteolytic activity when compared to the other strains. Significant difference was found in salivary IL-1β levels between the non-albicans Candida and control strains (P < 0.002). The present findings showed differences in proteolytic activity among the non-albicans Candida strains. The increased IL-1β concentration may be one of the host response components associated with non-albicans Candida infection.

  19. Gentian violet exhibits activity against biofilms formed by oral Candida isolates obtained from HIV-infected patients.

    PubMed

    Traboulsi, Rana S; Mukherjee, Pranab K; Chandra, Jyotsna; Salata, Robert A; Jurevic, Richard; Ghannoum, Mahmoud A

    2011-06-01

    The effect of gentian violet against Candida albicans and non-Candida albicans biofilms formed on polymethylmethacrylate strips was evaluated using a dry weight assay and confocal laser scanning microscopy. The ability of gentian violet to inhibit Candida albicans germination was also assessed. Gentian violet activity against Candida biofilms was demonstrated by a reduction in dry weight, disruption of biofilm architecture, and reduced biofilm thickness. Additionally, gentian violet inhibited Candida germination in a concentration-dependent manner.

  20. Candida albicans susceptibility to lactoperoxidase-generated hypoiodite

    PubMed Central

    Ahariz, Mohamed; Courtois, Philippe

    2010-01-01

    In vivo, lactoperoxidase produces hypothiocyanite (OSCN−) from thiocyanate (SCN−) in the presence of hydrogen peroxide (H2O2); in vitro, iodide (I−) can be oxidized into hypoiodite (OI−) by this enzyme. The aim of this study was to compare in vitro the anti-Candida effect of iodide versus thiocyanate used as lactoperoxidase substrate to prevent Candida biofilms development. Candida albicans ATCC 10231 susceptibility upon both peroxidase systems was tested in three different experimental designs: (i) in a liquid culture medium, (ii) in an interface model between solid culture medium and gel containing the enzymic systems, (iii) in a biofilm model onto titanium and acrylic resin. Yeast growth in liquid medium was monitored by turbidimetry at 600 nm. Material-adherent yeast biomass was evaluated by the tetrazolium salt MTT method. The iodide-peroxidase system has been shown to inhibit Candida biofilm formation at lower substrate concentrations (~200 fold less H2O2 donor) and for longer incubation periods than the thiocyanate-peroxidase system. In conclusion, efficiency of lactoperoxidase-generated OI− to prevent C. albicans biofilm development allows refining iodine antifungal use in ex vivo conditions. PMID:23662084

  1. Microplate Bioassay for Determining Substrate Selectivity of "Candida rugosa" Lipase

    ERIC Educational Resources Information Center

    Wang, Shi-zhen; Fang, Bai-shan

    2012-01-01

    Substrate selectivity of "Candida rugosa" lipase was tested using "p"-nitrophenyl esters of increasing chain length (C[subscript 1], C[subscript 7], C[subscript 15]) using the high-throughput screening method. A fast and easy 96-well microplate bioassay was developed to help students learn and practice biotechnological specificity screen. The…

  2. [Candida arthritis of the TM joint complicating chronic otitis media].

    PubMed

    Semlali, S; Nassar, I; Fikri, M; El Quessar, A; El Hassani, Mr; Chakir, N; Jiddane, M

    2004-11-01

    Infectious arthritis of the temporomandibular joint is very uncommon, and arthritis of the TM joint as a result of candida albicans infection has not previously been reported. The authors describe a patient treated for chronic otitis media complicated by arthritis of the temporomandibular joint. The diagnosis was made using CT scan and bacteriologic sampling.

  3. COMPARISON BETWEEN FOUR USUAL METHODS OF IDENTIFICATION OF Candida SPECIES

    PubMed Central

    SOUZA, Margarida Neves; ORTIZ, Stéfanie Otowicz; MELLO, Marcelo Martins; OLIVEIRA, Flávio de Mattos; SEVERO, Luiz Carlos; GOEBEL, Cristine Souza

    2015-01-01

    SUMMARY Infection by Candidaspp. is associated with high mortality rates, especially when treatment is not appropriate and/or not immediate. Therefore, it is necessary to correctly identify the genus and species of Candida. The aim of this study was to compare the identification of 89 samples of Candida spp. by the manual methods germ tube test, auxanogram and chromogenic medium in relation to the ID 32C automated method. The concordances between the methods in ascending order, measured by the Kappa index were: ID 32C with CHROMagar Candida(κ = 0.38), ID 32C with auxanogram (κ = 0.59) and ID 32C with germ tube (κ = 0.9). One of the species identified in this study was C. tropicalis,which demonstrated a sensitivity of 46.2%, a specificity of 95.2%, PPV of 80%, NPV of 81.1%, and an accuracy of 80.9% in tests performed with CHROMagar Candida;and a sensitivity of 76.9%, a specificity of 96.8%, PPV of 90.9%, NPV of 91%, and an accuracy of 91% in the auxanogram tests. Therefore, it is necessary to know the advantages and limitations of methods to choose the best combination between them for a fast and correct identification of Candidaspecies. PMID:26422150

  4. Identification of Candida spp. by phenotypic tests and PCR

    PubMed Central

    Marinho, Sandra Aparecida; Teixeira, Alice Becker; Santos, Otávio Silveira; Cazanova, Ricardo Flores; Ferreira, Carlos Alexandre Sanchez; Cherubini, Karen; de Oliveira, Sílvia Dias

    2010-01-01

    The correct identification of Candida species is of great importance, as it presents prognostic and therapeutical significance, allowing an early and appropriate antifungical therapy. The purpose of this study was to identify isolates of Candida spp. from oral mucosa of 38 patients with oral candidosis evaluated in 2004 by phenotypic methods and PCR, discriminating C. albicans from the other Candida species. The tests used for phenotypic analysis were germ-tube and chlamydoconidia production, culture in CHROMAgar™ Candida, carbohydrate assimilation test, growth at 45ºC and culture in Tween 80 agar. Genotypic confirmation was performed by PCR. Phenotypic tests showed that 63.2% strains formed germ-tubes, 73.7% produced chlamydoconidia, and 63.2% showed green colonies in chromogenic medium, presumptively indicating C. albicans or C. dubliniensis. The carbohydrate assimilation test confirmed these results. A total of 21% strains were identified as C. krusei and 13.2% were indicative of C. tropicalis. Of these later strains, three produced chlamydoconidia. The association of other phenotypic tests with culture in Tween 80 agar identified 95.8% of strains as C. albicans and 4.2% as C. dubliniensis. All 24 strains indicative of C. albicans and C. dubliniensis were confirmed by PCR as C. albicans. PMID:24031493

  5. Invasive Infections with Multidrug-Resistant Yeast Candida auris, Colombia

    PubMed Central

    Morales-López, Soraya E.; Parra-Giraldo, Claudia M.; Ceballos-Garzón, Andrés; Martínez, Heidys P.; Rodríguez, Gerson J.; Álvarez-Moreno, Carlos A.

    2017-01-01

    Candida auris is an emerging multidrug-resistant fungus that causes a wide range of symptoms. We report finding 17 cases of C. auris infection that were originally misclassified but correctly identified 27.5 days later on average. Patients with a delayed diagnosis of C. auris had a 30-day mortality rate of 35.2%. PMID:27983941

  6. In vitro shoot growth of Brugmansia x candida Pers.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this study was to improve the growth of in vitro shoot cultures of Brugmansia × candida 'Creamsickle'. Several mineral nutrient experiments were conducted to determine the effect of NH4+, NO3-, K+, FeSO4/EDTA, ZnSO4, MnSO4, and CuSO4 on quality, leaf width and length, size and weigh...

  7. [Suppression of activity of Candida albicans proteinases by cobalt chloride].

    PubMed

    Kutyreva, M P; Mukhametzianova, A R; Ulakhovich, N A

    2012-01-01

    Influence of cobalt (II) chloride on the system of Candida albicans proteinase (SAP C. alb.) (both in solution and immobilized on a surface of nitrocellulose membranes) has been investigated. In solution cobalt chloride inactivated inducible but not constitute enzyme. In the heterogenous sytem proteolitical effect of the cobalt ion on inductible proteinase was also observed.

  8. Inhibition of Candida albicans by methanethiol produced by Brevibacterium linens.

    PubMed

    Lewis, B A

    1985-10-01

    Brevibacterium linens was screened for antifungal activity against Candida albicans using several antibiotic assay methods. The growth of C. albicans was inhibited only when the dual culture assay method was employed and using methionine-supplemented media. Results suggest that methanethiol which is produced by B. linens' utilization of methionine is the agent inhibitory to C. albicans' growth.

  9. Modulation techniques

    NASA Technical Reports Server (NTRS)

    Schilling, D. L.

    1982-01-01

    Bandwidth efficient digital modulation techniques, proposed for use on and/or applied to satellite channels, are reviewed. In a survey of recent works on digital modulation techniques, the performance of several schemes operating in various environments are compared. Topics covered include: (1) quadrature phase shift keying; (2) offset - QPSK and MSK; (3) combined modulation and coding; and (4) spectrally efficient modulation techniques.

  10. Hemolytic Activities of the Candida Species in Liquid Medium

    PubMed Central

    Malcok, Hilal Kuzucu; Aktas, Esin; Ayyildiz, Ahmet; Yigit, Nimet; Yazgi, Halil

    2009-01-01

    Objective The aim of this study was to evaluate the in vitro hemolytic activities of 107 Candida strains isolated from different clinical samples in liquid medium, and to examine the impact of glucose on this activity. Materials and Methods A total of 107 Candida isolates representing seven species (C. albicans, n=28; C. glabrata, n=23; C. tropicalis, n=17; C. parapsilosis, n=16; C. kefyr, n=14; C. krusei, n=5; C. guilliermondii, n=4) were included in the study. The hemolytic activities of the strains were tested on two different Sabouraud dextrose liquid media (SDB) containing 7% defibrinated human blood, one of which is supplemented with 3% glucose and the other without glucose. Cultures were evaluated at the end of a 48-hour incubation. The hemolysis in the media was detected spectrophotometrically by measuring the amount of released hemoglobin and compared with a standard hemolysate which was prepared prior to testing. The degree of hemolysis (percentage value) by an individual strain was calculated according to the following formula below: (Absorbance of supernatant media at 540 nm / Absorbance of standard hemolysate at 540 nm X 100). Results In the liquid medium without glucose, strains generally produced hemolysis at low levels. The degree of hemolysis produced by all species increased noticeably in the liquid medium with glucose. Strains of C. albicans and C.kefyr had demonstrated significant hemolytic activity, whereas others had lower activity. C. parapsilosis exerted very little hemolytic activity in the medium with glucose and showed no activity in the medium without glucose. Conclusion The hemolytic activities of most Candida species was found to be higher in the human blood-enriched SDB medium containing 3% additive glucose than in the one free from additives. This result indicates that increased blood glucose concentration may contribute to increased hemolytic activity in Candida species, and it suggests a parallel with possible pathogenesis of

  11. Molecular epidemiology, phylogeny and evolution of Candida albicans.

    PubMed

    McManus, Brenda A; Coleman, David C

    2014-01-01

    A small number of Candida species form part of the normal microbial flora of mucosal surfaces in humans and may give rise to opportunistic infections when host defences are impaired. Candida albicans is by far the most prevalent commensal and pathogenic Candida species. Several different molecular typing approaches including multilocus sequence typing, multilocus microsatellite typing and DNA fingerprinting using C. albicans-specific repetitive sequence-containing DNA probes have yielded a wealth of information regarding the epidemiology and population structure of this species. Such studies revealed that the C. albicans population structure consists of multiple major and minor clades, some of which exhibit geographical or phenotypic enrichment and that C. albicans reproduction is predominantly clonal. Despite this, losses of heterozygosity by recombination, the existence of a parasexual cycle, toleration of a wide range of aneuploidies and the recent description of viable haploid strains have all demonstrated the extensive plasticity of the C. albicans genome. Recombination and gross chromosomal rearrangements are more common under stressful environmental conditions, and have played a significant role in the evolution of this opportunistic pathogen. Surprisingly, Candida dubliniensis, the closest relative of C. albicans exhibits more karyotype variability than C. albicans, but is significantly less adaptable to unfavourable environments. This disparity most likely reflects the evolutionary processes that occurred during or soon after the divergence of both species from their common ancestor. Whilst C. dubliniensis underwent significant gene loss and pseudogenisation, C. albicans expanded gene families considered to be important in virulence. It is likely that technological developments in whole genome sequencing and data analysis in coming years will facilitate its routine use for population structure, epidemiological investigations, and phylogenetic analyses of

  12. Development of Two Molecular Approaches for Differentiation of Clinically Relevant Yeast Species Closely Related to Candida guilliermondii and Candida famata

    PubMed Central

    Feng, Xiaobo; Wu, Jingsong; Ling, Bo; Yang, Xianwei; Liao, Wanqing

    2014-01-01

    The emerging pathogens Candida palmioleophila, Candida fermentati, and Debaryomyces nepalensis are often misidentified as Candida guilliermondii or Candida famata in the clinical laboratory. Due to the significant differences in antifungal susceptibilities and epidemiologies among these closely related species, a lot of studies have focused on the identification of these emerging yeast species in clinical specimens. Nevertheless, limited tools are currently available for their discrimination. Here, two new molecular approaches were established to distinguish these closely related species. The first approach differentiates these species by use of restriction fragment length polymorphism analysis of partial internal transcribed spacer 2 (ITS2) and large subunit ribosomal DNA with the enzymes BsaHI and XbaI in a double digestion. The second method involves a multiplex PCR based on the intron size differences of RPL18, a gene coding for a protein component of the large (60S) ribosomal subunit, and species-specific amplification. These two methods worked well in differentiation of these closely related yeast species and have the potential to serve as effective molecular tools suitable for laboratory diagnoses and epidemiological studies. PMID:24951804

  13. Development of two molecular approaches for differentiation of clinically relevant yeast species closely related to Candida guilliermondii and Candida famata.

    PubMed

    Feng, Xiaobo; Wu, Jingsong; Ling, Bo; Yang, Xianwei; Liao, Wanqing; Pan, Weihua; Yao, Zhirong

    2014-09-01

    The emerging pathogens Candida palmioleophila, Candida fermentati, and Debaryomyces nepalensis are often misidentified as Candida guilliermondii or Candida famata in the clinical laboratory. Due to the significant differences in antifungal susceptibilities and epidemiologies among these closely related species, a lot of studies have focused on the identification of these emerging yeast species in clinical specimens. Nevertheless, limited tools are currently available for their discrimination. Here, two new molecular approaches were established to distinguish these closely related species. The first approach differentiates these species by use of restriction fragment length polymorphism analysis of partial internal transcribed spacer 2 (ITS2) and large subunit ribosomal DNA with the enzymes BsaHI and XbaI in a double digestion. The second method involves a multiplex PCR based on the intron size differences of RPL18, a gene coding for a protein component of the large (60S) ribosomal subunit, and species-specific amplification. These two methods worked well in differentiation of these closely related yeast species and have the potential to serve as effective molecular tools suitable for laboratory diagnoses and epidemiological studies.

  14. 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.

  15. Metschnikowia santaceciliae, Candida hawaiiana, and Candida kipukae, three new yeast species associated with insects of tropical morning glory.

    PubMed

    Lachance, Marc André; Bowles, Jane M; Starmer, William T

    2003-03-01

    A new haplontic heterothallic species of Metschnikowia and two related asexual yeast species were discovered in morning glory flowers and associated insects. Metschnikowia santaceciliae came from Conotelus (Coleoptera: Nitidulidae) and other insect species associated with flowers of Ipomoea indica (purple morph) in Costa Rica. Candida hawaiiana and Candida kipukae were found in I. indica (syn. I. acuminata) and its insects in Hawai'i, and the former was also isolated in a specimen of Conotelus collected on Merremia tuberosa (Convolvulaceae) in Costa Rica. The three species have nearly identical physiological profiles, typical of the genus Metschnikowia. The sequences of the D1/D2 domains of their large subunit ribosomal DNA confirm that the species belong to the Metschnikowia clade, even though they share a very low degree of inter-relatedness. M. santaceciliae is a sister species to Metschnikowia continentalis. C. kipukae is a basal member of the large-spored Metschnikowia subclade, and C. hawaiiana has a weak affinity to Metschnikowia agaves. Two of the three species appear to be endemic. The type cultures are: Metschnikowia santaceciliae, strains UWO(PS)01-517a1=CBS 9148=NRRL Y-27475 (h(+, holotype) and UWO(PS)01-520a1=CBS 9149=NRRL Y-27476 (h-, isotype); Candida hawaiiana, strain UWO(PS)91-698.3=CBS 9146=NRRL Y-27473; Candida kipukae, strain UWO(PS)00-669.2=CBS 9147=NRRL Y-27474.

  16. Micafungin triggers caspase-dependent apoptosis in Candida albicans and Candida parapsilosis biofilms, including caspofungin non-susceptible isolates.

    PubMed

    Shirazi, F; Kontoyiannis, D P

    2015-01-01

    Candida biofilms play an important role in infections associated with medical devices and are resistant to antifungals. We hypothesized that the echinocandin micafungin (MICA) exerts an enhanced antifungal activity against caspofungin (CAS)-susceptible (CAS-S) and CAS-non-susceptible (CAS-NS) Candida albicans and Candida parapsilosis which is at least in part through apoptosis, even in the biofilm environment. Apoptosis was characterized by detecting reactive oxygen species (ROS) accumulation, depolarization of mitochondrial membrane potential (MMP), DNA fragmentation, lack of plasma membrane integrity, and metacaspase activation following exposure of Candida biofilm to MICA for 3h at 37°C in RPMI 1640 medium. The minimum inhibitory concentration was higher for CAS (2.0-16.0 μg/mL) than for MICA (1.0-8.0 μg/mL) for Candida biofilms. Elevated intracellular ROS levels and depolarization of MMP was evident in CAS-S C. albicans (3.0-4.2 fold) and C. parapsilosis (4.8-5.4 fold) biofilms compared with CAS-NS (1.2 fold) after exposure to MICA (0.25x-1xMIC). Elevated intracellular ROS levels and depolarization of MMP was evident in CAS-S C. albicans (3.0-4.2 fold) and C. parapsilosis (4.8-5.4 fold) biofilms compared with CAS-NS (1.2 fold) after exposure to MICA (0.25x-1xMIC). Finally higher ß-1, 3 glucan levels were seen in sessile cells compared to planktonic cells, especially in CAS-NS strains. MICA treatment might induce a metacaspase-dependent apoptotic process in biofilms of both CAS-S C. albicans and C. parapsilosis, and to some degree in CAS-NS strains.

  17. Photoinactivation of single and mixed biofilms of Candida albicans and non-albicans Candida species using Phorodithazine(®).

    PubMed

    Carmello, Juliana Cabrini; Alves, Fernanda; Mima, Ewerton Garcia de Oliveira; Jorge, Janaina Habib; Bagnato, Vanderlei Salvador; Pavarina, Ana Cláudia

    2017-03-01

    This study evaluated the effectiveness of antimicrobial photodynamic therapy (aPDT) mediated by Photodithazine(®) (PDZ) formulated in hydrogel, in the inactivation of mono and duo-species biofilms of Candida albicans, Candida glabrata and Candida tropicalis. Standardized suspensions of each strain were prepared and after biofilm formation, mono-species were treated with 150 and 175mg/L of PDZ for 20min (pre-irradiation time), and exposed to LED light at a dose of 37.5J/cm(2) (660nm). The duo-species biofilms (C. albicans+C. glabrata and C. albicans+C. tropicalis) were treated with 150mg/L of PDZ and light. Additional samples were treated with PDZ or light only, and the control did not receive any treatment. Next, microbiological evaluation was performed by spreading the cells on Sabouraud Dextrose Agar and CHROMagar Candida for colony forming units (CFU/mL). Moreover, the total biomass of biofilm was verified using the crystal violet staining assay (CV). The data were submitted to ANOVA and Tukey post-hoc (α=0.05). The use of PDZ 150mg/L promoted a reduction of 1.0, 1.2, 1.5 log10 in the viability of C. glabrata, C. albicans and C. tropicalis, respectively. The same concentration reduced in 1.0 log10 the viability of each species grown as duo-species biofilms. The crystal violet assay showed that the use of 150mg/L reduced 24.4%, 39.2% and 43.7% of the total biomass of C. albicans, C. tropicalis and C. glabrata, respectively. aPDT did not reduce the total biomass to the duo-species biofilms. Thus, PDZ-mediated aPDT was more effective in the inactivation of mono-species biofilms of Candida spp. compared with duo-species biofilm.

  18. Detailed comparison of Candida albicans and Candida glabrata biofilms under different conditions and their susceptibility to caspofungin and anidulafungin.

    PubMed

    Kucharíková, Sona; Tournu, Hélène; Lagrou, Katrien; Van Dijck, Patrick; Bujdáková, Helena

    2011-09-01

    Candida biofilm development can be influenced by diverse factors such as substrate, culture medium, carbohydrate source and pH. We have analysed biofilm formation of Candida albicans SC5314 and Candida glabrata ATCC 2001 wild-type strains in the presence of different media (RPMI 1640 versus YNB) and using different pH values (pH 5.6 or 7.0). We determined adhesion and biofilm formation on polystyrene, changes in the expression of adhesin genes during these processes and the susceptibility of mature biofilms to echinocandins. Biofilms formed on polystyrene by both Candida species proved to be influenced strongly by the composition of the medium rather than pH. C. albicans and C. glabrata formed thicker biofilms in RPMI 1640 medium, whereas in YNB medium, both species manifested adhesion rather than characteristic multilayer biofilm architecture. The stimulated biofilm formation in RPMI 1640 medium at pH 7.0 corroborated positively with increased expression of adhesin genes, essential to biofilm formation in vitro, including ALS3 and EAP1 in C. albicans and EPA6 in C. glabrata. The thicker biofilms grown in RPMI 1640 medium were more tolerant to caspofungin and anidulafungin than YNB-grown biofilms. We also observed that mature C. glabrata biofilms were less susceptible in RPMI 1640 medium to echinocandins than C. albicans biofilms. Environmental conditions, i.e. medium and pH, can significantly affect not only biofilm architecture, but also the expression profile of several genes involved during the different stages of biofilm development. In addition, growth conditions may also influence the antifungal-susceptibility profile of fungal populations within biofilm structures. Therefore, before designing any experimental biofilm set-up, it is important to consider the potential influence of external environmental factors on Candida biofilm development.

  19. Elevated chitin content reduces the susceptibility of Candida species to caspofungin.

    PubMed

    Walker, Louise A; Gow, Neil A R; Munro, Carol A

    2013-01-01

    The echinocandin antifungal drugs inhibit synthesis of the major fungal cell wall polysaccharide β(1,3)-glucan. Echinocandins have good efficacy against Candida albicans but reduced activity against other Candida species, in particular Candida parapsilosis and Candida guilliermondii. Treatment of Candida albicans with a sub-MIC level of caspofungin has been reported to cause a compensatory increase in chitin content and to select for sporadic echinocandin-resistant FKS1 point mutants that also have elevated cell wall chitin. Here we show that elevated chitin in response to caspofungin is a common response in various Candida species. Activation of chitin synthesis was observed in isolates of C. albicans, Candida tropicalis, C. parapsilosis, and C. guilliermondii and in some isolates of Candida krusei in response to caspofungin treatment. However, Candida glabrata isolates demonstrated no exposure-induced change in chitin content. Furthermore, isolates of C. albicans, C. krusei, C. parapsilosis, and C. guilliermondii which were stimulated to have higher chitin levels via activation of the calcineurin and protein kinase C (PKC) signaling pathways had reduced susceptibility to caspofungin. Isolates containing point mutations in the FKS1 gene generally had higher chitin levels and did not demonstrate a further compensatory increase in chitin content in response to caspofungin treatment. These results highlight the potential of increased chitin synthesis as a potential mechanism of tolerance to caspofungin for the major pathogenic Candida species.

  20. In vitro antimicrobial properties of coconut oil on Candida species in Ibadan, Nigeria.

    PubMed

    Ogbolu, D O; Oni, A A; Daini, O A; Oloko, A P

    2007-06-01

    The emergence of antimicrobial resistance, coupled with the availability of fewer antifungal agents with fungicidal actions, prompted this present study to characterize Candida species in our environment and determine the effectiveness of virgin coconut oil as an antifungal agent on these species. In 2004, 52 recent isolates of Candida species were obtained from clinical specimens sent to the Medical Microbiology Laboratory, University College Hospital, Ibadan, Nigeria. Their susceptibilities to virgin coconut oil and fluconazole were studied by using the agar-well diffusion technique. Candida albicans was the most common isolate from clinical specimens (17); others were Candida glabrata (nine), Candida tropicalis (seven), Candida parapsilosis (seven), Candida stellatoidea (six), and Candida krusei (six). C. albicans had the highest susceptibility to coconut oil (100%), with a minimum inhibitory concentration (MIC) of 25% (1:4 dilution), while fluconazole had 100% susceptibility at an MIC of 64 microg/mL (1:2 dilution). C. krusei showed the highest resistance to coconut oil with an MIC of 100% (undiluted), while fluconazole had an MIC of > 128 microg/mL. It is noteworthy that coconut oil was active against species of Candida at 100% concentration compared to fluconazole. Coconut oil should be used in the treatment of fungal infections in view of emerging drug-resistant Candida species.

  1. Phylogeny and evolution of the aspartyl protease family from clinically relevant Candida species.

    PubMed

    Parra-Ortega, B; Cruz-Torres, H; Villa-Tanaca, L; Hernández-Rodríguez, C

    2009-05-01

    Aspartyl proteases are a class of enzymes that include the yeast aspartyl proteases and secreted aspartyl protease (Sap) superfamilies. Several Sap superfamily members have been demonstrated or suggested as virulence factors in opportunistic pathogens of the genus Candida. Candida albicans, Candida tropicalis, Candida dubliniensis and Candida parapsilosis harbour 10, four, eight and three SAP genes, respectively. In this work, genome mining and phylogenetic analyses revealed the presence of new members of the Sap superfamily in C. tropicalis (8), Candida guilliermondii (8), C. parapsilosis(11) and Candida lusitaniae (3). A total of 12 Sap families, containing proteins with at least 50% similarity, were discovered in opportunistic, pathogenic Candida spp. In several Sap families, at least two subfamilies or orthologous groups were identified, each defined by > 90% sequence similitude, functional similarity and synteny among its members. No new members of previously described Sap families were found in a Candida spp. clinical strain collection; however, the universality of SAPT gene distribution among C. tropicalis strains was demonstrated. In addition, several features of opportunistic pathogenic Candida species, such as gene duplications and inversions, similitude, synteny, putative transcription factor binding sites and genome traits of SAP gene superfamily were described in a molecular evolutionary context.

  2. 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.

  3. Sensitive and rapid RT-qPCR quantification of pathogenic Candida species in human blood.

    PubMed

    Ogata, Kiyohito; Matsuda, Kazunori; Tsuji, Hirokazu; Nomoto, Koji

    2015-10-01

    For accurate diagnosis and appropriate treatment of candidiasis, we developed a highly sensitive quantitative RT-PCR (RT-qPCR) system for five Candida species that have been reported to be the major causes of bloodstream fungal infection (Candida albicans, Candida glabrata, Candida tropicalis, Candida parapsilosis, and Candida krusei), together with a system for all pathogenic Candida species. Cells of each fungal species spiked into human peripheral blood (PB) were specifically detected at a lower detection limit of 10(0) cell/1 mL PB by this system using the newly developed specific primer sets targeting 18S or 26S rRNA of the five Candida species, together with the existing group primer set. The total count of the five Candida spp. as the sum of those obtained by using the five species primer sets was equivalent to the count obtained by using the group primer set, indicating that the group set covered the major five Candida spp. in human blood with the same degree of accuracy as the species primer sets. The RT-qPCR counts of the Candida species were in good agreement with CFU counts obtained by their culture on CHROMagar™, with a lower detection limit of 10(0)cell/mL of PB. Candida rRNA molecules were stably stored for at least 7 days at 4°C by keeping the blood specimens in an RNA stabilizing reagent. These results strongly suggest that this sensitive system is useful for accurate and rapid diagnosis of Candida bloodstream infections.

  4. Candida and other yeasts of clinical importance in Aseer region, southern Saudi Arabia

    PubMed Central

    Hamid, Mohamed E.; Assiry, Mohammed M.; Joseph, Martin R.; Haimour, Waleed O.; Abdelrahim, Ihab M.; Al-Abed, Fatin; Fadul, Abdalla N.; Al-Hakami, Ahmed M.

    2014-01-01

    Objectives: To isolate, identify, and determine the prevalence of Candida and other yeasts of clinical importance in Aseer region, Saudi Arabia. Methods: This is a cross-sectional study involving retrospective analysis of 6100 samples submitted to the Microbiology Laboratory, Aseer Central Hospital, Abha, Saudi Arabia between 2011 and 2012, and prospective isolation and identification of 84 isolates recovered from various clinical specimens presented to the Microbiology Laboratory between 2012 and 2013 using the classic morphological schemes and the Vitek 2 automated system. Results: The results of the retrospective analysis (2011-2012) indicated that of the 6100 various clinical specimens submitted to the routine microbiology analysis, 143 (2.35%) revealed the presence of Candida spp. The distribution of the 143 Candida spp. according to specimens was as follows: urine 72%, sputum 10.5%, endotracheal tube 7%, blood 4.2%, catheter tip 2.1%, throat swab 2.1%, eye swab 0.7%, wound exudates 0.7%, and cerebrospinal fluid 0.7%. The results of the prospective study (2012-2013), which involved the identification of yeast recovered from 84 specimens indicated that Candida albicans 28.6% was the predominant species, followed by Candida parapsilosis 21.4%, Candida tropicalis 14.3%, and Candida lusitaniae 9.5%. Conclusions: Along with the commonly encountered Candida albicans, Candida parapsilosis, Candida tropicalis, and Candida lusitaniae were detected with significant rates. Many other Candida species and some other pathogenic yeasts have been detected for the first time in the region. Urinary tract samples were the main source of Candida species. PMID:25316465

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  6. Single-Molecule Imaging and Functional Analysis of Als Adhesins and Mannans during Candida albicans Morphogenesis

    PubMed Central

    Beaussart, Audrey; Alsteens, David; El-Kirat-Chatel, Sofiane; Lipke, Peter N.; Kucharíková, Sona; Van Dijck, Patrick; Dufrêne, Yves F.

    2012-01-01

    Cellular morphogenesis in the fungal pathogen Candida albicans is associated with changes in cell wall composition that play important roles in biofilm formation and immune responses. Yet, how fungal morphogenesis modulates the biophysical properties and interactions of the cell surface molecules is poorly understood, mainly owing to the paucity of high-resolution imaging techniques. Here, we use single-molecule atomic force microscopy to localize and analyze the key components of the surface of living C. albicans cells during morphogenesis. We show that the yeast-to-hypha transition leads to a major increase in the distribution, adhesion, unfolding and extension of Als adhesins and their associated mannans on the cell surface. We also find that morphogenesis dramatically increases cell surface hydrophobicity. These molecular changes are critical for microbe-host interactions, including adhesion, colonization, and biofilm formation. The single-molecule experiments presented here offer promising prospects for understanding how microbial pathogens use cell surface molecules to modulate biofilm and immune interactions. PMID:23145462

  7. Opportunistic pathogen Candida albicans elicits a temporal response in primary human mast cells.

    PubMed

    Lopes, José Pedro; Stylianou, Marios; Nilsson, Gunnar; Urban, Constantin F

    2015-07-20

    Immunosuppressed patients are frequently afflicted with severe mycoses caused by opportunistic fungal pathogens. Besides being a commensal, colonizing predominantly skin and mucosal surfaces, Candida albicans is the most common human fungal pathogen. Mast cells are present in tissues prone to fungal colonization being expectedly among the first immune cells to get into contact with C. albicans. However, mast cell-fungus interaction remains a neglected area of study. Here we show that human mast cells mounted specific responses towards C. albicans. Collectively, mast cell responses included the launch of initial, intermediate and late phase components determined by the secretion of granular proteins and cytokines. Initially mast cells reduced fungal viability and occasionally internalized yeasts. C. albicans could evade ingestion by intracellular growth leading to cellular death. Furthermore, secreted factors in the supernatants of infected cells recruited neutrophils, but not monocytes. Late stages were marked by the release of cytokines that are known to be anti-inflammatory suggesting a modulation of initial responses. C. albicans-infected mast cells formed extracellular DNA traps, which ensnared but did not kill the fungus. Our results suggest that mast cells serve as tissue sentinels modulating antifungal immune responses during C. albicans infection. Consequently, these findings open new doors for understanding fungal pathogenicity.

  8. Virulence attributes and genetic variability of oral Candida albicans and Candida tropicalis isolates.

    PubMed

    da Costa, Karen Regina Carim; Ferreira, Joseane Cristina; Lavrador, Marco Aurélio Sicchiroli; Baruffi, Marcelo Dias; Candido, Regina Celia

    2012-05-01

    The wide spectrum of candidiasis and its clinical importance encourage the research with the purpose of clarifying the mechanisms of pathogenicity and identification of virulence factors of Candida sp. Therefore, the aim of this study was to verify the adhesion capacity, protease activity and genotypic diversity of oral C. albicans and C. tropicalis isolates. The adhesion ability to the extracellular matrix glycoproteins laminin and fibronectin was evaluated using the ELISA technique. The research of proteases was carried out in agar plate containing bovine albumin and through a quantitative method in buffer solution containing haemoglobin. Intra and interspecies polymorphisms was verified through random amplified polymorphic DNA (RAPD) technique. All C. albicans and C. tropicalis isolates binded to immobilised laminin and fibronectin. Ca33 and Ct13 isolates had relative adhesion index significantly higher than the other isolates for both glycoproteins (P < 0.001). Protease activity was observed in all isolates of C. albicans using either the semi-quantitative or quantitative assay. The protease activity of C. tropicalis was better detected through the quantitative assay. The genotypic diversity by RAPD revealed a heterogeneous population in both species. Nevertheless, C. tropicalis presented higher genetic variability than C. albicans strains.

  9. Candida species diversity and antifungal susceptibility patterns in oral samples of HIV/AIDS patients in Baja California, Mexico.

    PubMed

    Clark-Ordóñez, Isadora; Callejas-Negrete, Olga A; Aréchiga-Carvajal, Elva T; Mouriño-Pérez, Rosa R

    2016-09-14

    Candidiasis is the most common opportunistic fungal infection in HIV patients. The aims of this study were to identify the prevalence of carriers of Candida, Candida species diversity, and in vitro susceptibility to antifungal drugs. In 297 HIV/AIDS patients in Baja California, Mexico, Candida strains were identified by molecular methods (PCR-RFLP) from isolates of oral rinses of patients in Tijuana, Mexicali, and Ensenada. 56.3% of patients were colonized or infected with Candida In Tijuana, there was a significantly higher percentage of carriers (75.5%). Out of the 181 strains that were isolated, 71.8% were Candida albicans and 28.2% were non-albicans species. The most common non-albicans species was Candida tropicalis (12.2%), followed by Candida glabrata (8.3%), Candida parapsilosis (2.2%), Candida krusei (1.7%), and Candida guilliermondii (1.1%). Candida dubliniensis was not isolated. Two associated species were found in 11 patients. In Mexicali and Ensenada, there was a lower proportion of Candida carriers compared to other regions in Mexico and worldwide, however, in Tijuana, a border town with many peculiarities, a higher carrier rate was found. In this population, only a high viral load was associated with oral Candida carriers. Other factors such as gender, use of antiretroviral therapy, CD4(+) T-lymphocyte levels, time since diagnosis, and alcohol/ tobacco consumption, were not associated with Candida carriers.

  10. The emergence of non-albicans Candida species as causes of invasive candidiasis and candidemia.

    PubMed

    Sobel, Jack D

    2006-11-01

    The last three decades have seen an expanding pool of high-risk patients susceptible to the opportunistic pathogen Candida. Accordingly, a dramatic increase in nosocomial blood stream infections (BSIs) due to Candida spp has been reported throughout the world, starting in tertiary care centers and spreading to community hospitals. This absolute increase in Candida BSIs was accompanied by both an absolute and then a proportional increase in invasive infection caused by reduced fluconazole-susceptible non-albicans Candida spp. Currently, the incidence trend of BSI has stabilized, and Candida albicans remains the most common species causing fungal BSI. Clinicians must be aware of the importance and implications of non-albicans Candida spp when selecting antifungal drugs, although most studies have not shown significant outcome differences with use of the various antifungal classes.

  11. Candida bloodstream infection: a clinical microbiology laboratory perspective.

    PubMed

    Pongrácz, Júlia; Kristóf, Katalin

    2014-09-01

    The incidence of Candida bloodstream infection (BSI) has been on the rise in several countries worldwide. Species distribution is changing; an increase in the percentage of non-albicans species, mainly fluconazole non-susceptible C. glabrata was reported. Existing microbiology diagnostic methods lack sensitivity, and new methods need to be developed or further evaluation for routine application is necessary. Although reliable, standardized methods for antifungal susceptibility testing are available, the determination of clinical breakpoints remains challenging. Correct species identification is important and provides information on the intrinsic susceptibility profile of the isolate. Currently, acquired resistance in clinical Candida isolates is rare, but reports indicate that it could be an issue in the future. The role of the clinical microbiology laboratory is to isolate and correctly identify the infective agent and provide relevant and reliable susceptibility data as soon as possible to guide antifungal therapy.

  12. Osteomyelitis Caused by Candida glabrata in the Distal Phalanx

    PubMed Central

    Hibino, Naohito; Sairyo, Koichi; Yoshioka, Shinji; Yamano, Masahiro; Henmi, Tatsuhiko

    2014-01-01

    Osteomyelitis caused by Candida glabrata is rare and its optimal treatment is unknown. Here we report a case of osteomyelitis caused by C. glabrata in the distal phalanx in a 54-year-old woman. Despite partial resection of the nail and administering a 1-month course of antibiotics for paronychia, the local swelling remained and an osteolytic lesion was found. C. glabrata osteomyelitis of the distal phalanx was later diagnosed after curettage. Thereafter, the patient was treated with antifungal agents for 3 months. The infection eventually resolved, and radiological healing of the osteolytic lesion was achieved. Antifungal susceptibility testing should be performed in the case of osteomyelitis caused by nonalbicans Candida species, due to their resistance to fluconazole. PMID:25215255

  13. Candida glabrata infection in gastric carcinoma patient mimicking cutaneous histoplasmosis.

    PubMed

    Gugic, Dijana; Cleary, Timothy; Vincek, Vladimir

    2008-02-28

    Candida glabrata is the second most common Candida species detected among hospitalized patients in USA. In tissue C. glabrata present as yeasts, 3-5 microns in size, which are difficult to visualize on H&E stained slides but can be detected on Grocott methenamine silver (GMS) stained slides. The presence of yeasts only, without any hyphal elements, makes C. glabrata difficult to distinguish from Histoplasma capsulatum yeasts that are of similar size. Mycology culture is the method of choice for definitive identification of C. glabrata. Rapid identification is necessary, as mortality rate due to C. glabrata infection in immunocompromised patients is particularly high. We herein report a patient with inoperable gastric carcinoma, who developed cutaneous and septic form of C. glabrata infection.

  14. A Monoclonal Antibody Specific to Surface Antigen on Candida krusei

    PubMed Central

    Robert, Raymond; Faure, Odile; Carloti, Arnaud; Lebeau, Bernadette; Bernard, Christian; Marot-Leblond, Agnès; Grillot, Renée; Senet, Jean-Marcel

    1998-01-01

    A monoclonal antibody (MAb; MAb 6B3) which reacts specifically with a cell wall antigen found in all strains or isolates of Candida krusei was developed. MAb 6B3 was extensively tested by immunofluorescence assay for cross-reaction with many Candida, Cryptococcus, Saccharomyces, Trichosporon, and Rhodotorula species and was found to react only with the species C. krusei. The specific epitope is expressed on the surface of fungal cells and appears to reside on a protein moiety. Taking into account the increasing importance of fluconazole-resistant strains in nosocomial fungal infections, the very high degree of specificity of this MAb for C. krusei could be useful for the routine detection of C. krusei in culture or in tissue samples. PMID:9455893

  15. Growing Candida albicans Biofilms on Paper Support and Dynamic Conditions.

    PubMed

    Selow, Marcela Lima Cardoso; Rymovicz, Alinne Ulbrich Mores; Ribas, Cristina Rauen; Saad, Renata Simão; Rosa, Rosimeire Takaki; Rosa, Edvaldo Antonio Ribeiro

    2015-08-01

    A stainless steel paper-embedded biofilm reactor (PEBR) was developed for Candida spp. growth, permitting confluent distribution of nutrients by capillary diffusion through ordinary laboratory filter paper. Antibiogram disks were distributed along the filter paper rim, and the PEBR received 0.1 or 0.01 % crystal violet (CV) at 200 μL min(-1) and at 37 °C, for 48 h. CV was recovered from the disks and measured at 540 nm. Candida albicans SC5314 cells were applied onto antibiogram disks. The bioreactor was assembled, and YEPD broth was admitted (200 μL min(-1)) at 37 °C, for 72 h. Biofilm growth was estimated via the MTT reduction test. Controls were disks that received the same treatments, except for the fungus. The PEBR was considered high-throughput table, low-cost, and feasible to grow C. albicans biofilms.

  16. Anti-Candida activity of Brazilian medicinal plants.

    PubMed

    Duarte, Marta Cristina Teixeira; Figueira, Glyn Mara; Sartoratto, Adilson; Rehder, Vera Lúcia Garcia; Delarmelina, Camila

    2005-02-28

    Essential oils and ethanolic extracts from the leaves and/or roots of 35 medicinal plants commonly used in Brazil were screened for anti-Candida albicans activity. The oils were obtained by water-distillation using a Clevenger-type system. Essential oils from 13 plants showed anti-Candida activity, including Aloysia triphylla, Anthemis nobilis, Cymbopogon martini, Cymbopogon winterianus, Cyperus articulatus, Cyperus rotundus, Lippia alba, Mentha arvensis, Mikania glomerata, Mentha piperita, Mentha sp., Stachys byzantina, and Solidago chilensis. The ethanol extract was not effective at any of the concentrations tested. Chemical analyses showed the presence of compounds with known antimicrobial activity, including 1,8-cineole, geranial, germacrene-D, limonene, linalool, and menthol.

  17. Starvation survival of Candida albicans in various water microcosms.

    PubMed

    Chaieb, Kamel; Kouidhi, Bochra; Zmantar, Tarek; Mahdouani, Kacem; Bakhrouf, Amina

    2011-08-01

    Candida is a major Human pathogen causing a variety of infections and can survive for extended period of time in aquatic environment including marine and fresh water. In this study we compared a colorimetric XTT assay to colony forming units (CFU) count to evaluate the survival potential of Candida albicans incubated in water microcosms. Our results showed that cells maintain cultivability within a long period followed by a decline in cultivability and a drop of plate counts to less than 20 cell ml(-1) after 150 days in tap water, 190 days in rain water and 200 days in seawater. In addition we noted that 10% of cells viability was reached after 150 days in seawater, 180 days in rain water and 210 days in tap water. Molecular method confirms the persistence of C. albicans cells in water during long time starvation period.

  18. Killer system: a simple method for differentiating Candida albicans strains.

    PubMed Central

    Polonelli, L; Archibusacci, C; Sestito, M; Morace, G

    1983-01-01

    The killer effect of 37 species of Candida, Cryptococcus, Hansenula, Pichia, Rhodotorula, Saccharomyces, and Trichosporon on 100 Candida albicans isolates of human and animal origin was studied. All of the C. albicans cultures were sensitive to one or more killer yeasts. The factors affecting the killer phenomenon on C. albicans were investigated for realizing a simple system for the differentiation of the 100 C. albicans isolates. By using this system, it was possible to differentiate up to 512 isolates of C. albicans according to their susceptibility to the killer effect of nine selected killer yeasts. The use of this method as an epidemiological marker in the case of presumptive nosocomial infections due to C. albicans is also reported. Images PMID:6345575

  19. Endogenous Candida endophthalmitis and osteomyelitis associated with CARD9 deficiency.

    PubMed

    Jones, Nicholas; Garcez, Tomaz; Newman, William; Denning, David

    2016-03-03

    A 25-year-old woman presented with unilateral red eye and visual blur, and was found to have panuveitis with an inflammatory white mass at the macula, initially presumed to be Toxoplasma retinitis. After failure to respond, she underwent vitrectomy, which produced Candida albicans. Despite intraocular and systemic antifungal treatment, she lost all vision in that eye. Two years later, she developed unilateral hip osteomyelitis leading to total hip replacement and also revealing Candida infection. By clinical exome sequencing, she was then found to have caspase recruitment domain 9 (CARD9) deficiency, an autosomal recessive disorder that causes a specific susceptibility to candidal infections. She remains otherwise well but on lifelong fluconazole prophylaxis.

  20. In vitro evaluation of vincristine and fluconazole combination against Candida.

    PubMed

    Khan, Abdul Arif; Khurshid, Mohsin; Tawfik, A F

    2013-09-01

    Infections associated with cancer are a major scourge and cause of substantial morbidity and mortality in cancer patients. The aim of present study was to appraise the in vitro activity of anticancer agent vincristine and antifungal fluconazole alone and in combination against Candida spp. Results were interpreted in terms of fractional inhibitory concentration index (FICI). Antifungal activity of fluconazole showed marked synergism when used in combination with vincristine, with FICI ranging from 0.25-0.5 against different Candida spp. Although, the use of vincristine with fluconazole is always disputed due to its side effects including decreased peristalsis, but the present research can help to perform suitability analysis of fluconazole use in life threatening invasive candidiasis associated with cancer patients. In addition, the synergism in antifungal activity after using with vincristine also warrants further research in the direction of minimizing adverse reaction associated with combined use of fluconazole and vincristine.

  1. Two unlike cousins: Candida albicans and C. glabrata infection strategies

    PubMed Central

    Brunke, Sascha; Hube, Bernhard

    2013-01-01

    Candida albicans and C. glabrata are the two most common pathogenic yeasts of humans, yet they are phylogenetically, genetically and phenotypically very different. In this review, we compare and contrast the strategies of C. albicans and C. glabrata to attach to and invade into the host, obtain nutrients and evade the host immune response. Although their strategies share some basic concepts, they differ greatly in their outcome. While C. albicans follows an aggressive strategy to subvert the host response and to obtain nutrients for its survival, C. glabrata seems to have evolved a strategy which is based on stealth, evasion and persistence, without causing severe damage in murine models. However, both fungi are successful as commensals and as pathogens of humans. Understanding these strategies will help in finding novel ways to fight Candida, and fungal infections in general. PMID:23253282

  2. Candida dubliniensis Pneumonia: A Case Report and Review of Literature.

    PubMed

    Petty, Lindsay A; Gallan, Alexander J; Detrick, Jordan A; Ridgway, Jessica P; Mueller, Jeffrey; Pisano, Jennifer

    2016-10-01

    Candida dubliniensis is an uncommon species of Candida which has been implicated in fungal pneumonia only very rarely. We present the case of a 75-year-old man with laryngeal cancer undergoing chemotherapy on broad-spectrum antibiotics and tuberculosis therapy with blood and endotracheal cultures positive for C. dubliniensis. Subsequent autopsy was performed with postmortem lung cultures positive for C. dubliniensis and lung histopathology demonstrating an invasive fungal infection. Molecular analysis of the lung tissue confirmed the identity of the fungi as C. dubliniensis. Since its discovery as a pathogen in the oral cavities of HIV-positive patients, C. dubliniensis has been identified in a wide spectrum of clinical scenarios and anatomic locations but manifests only rarely as pneumonia. This report represents a novel case of C. dubliniensis pneumonia confirmed by culture, histopathology, and molecular identification.

  3. Innate immune cell response upon Candida albicans infection.

    PubMed

    Qin, Yulin; Zhang, Lulu; Xu, Zheng; Zhang, Jinyu; Jiang, Yuan-Ying; Cao, Yongbing; Yan, Tianhua

    2016-07-03

    Candida albicans is a polymorphic fungus which is the predominant cause of superficial and deep tissue fungal infections. This microorganism has developed efficient strategies to invade the host and evade host defense systems. However, the host immune system will be prepared for defense against the microbe by recognition of receptors, activation of signal transduction pathways and cooperation of immune cells. As a consequence, C. albicans could either be eliminated by immune cells rapidly or disseminate hematogenously, leading to life-threatening systemic infections. The interplay between Candida albicans and the host is complex, requiring recognition of the invaded pathogens, activation of intricate pathways and collaboration of various immune cells. In this review, we will focus on the effects of innate immunity that emphasize the first line protection of host defense against invaded C. albicans including the basis of receptor-mediated recognition and the mechanisms of cell-mediated immunity.

  4. Prevalence and antifungal susceptibility of Candida albicans and its related species Candida dubliniensis and Candida africana isolated from vulvovaginal samples in a hospital of Argentina.

    PubMed

    Theill, Laura; Dudiuk, Catiana; Morano, Susana; Gamarra, Soledad; Nardin, María Elena; Méndez, Emilce; Garcia-Effron, Guillermo

    2016-01-01

    Candida africana taxonomical status is controversial. It was proposed as a separate species within the Candida albicans species complex; however, phylogenetic analyses suggested that it is an unusual variety of C. albicans. The prevalence of C. albicans-related species (Candida dubliniensis and C. africana) as vulvovaginal pathogens is not known in Argentina. Moreover, data on antifungal susceptibility of isolates causing vulvovaginal candidiasis is scarce. The aims of this study were to establish the prevalence of C. dubliniensis and C. africana in vaginal samples and to evaluate the antifungal susceptibilities of vaginal C. albicans species complex strains. We used a molecular-based method coupled with a new pooled DNA extraction methodology to differentiate C. dubliniensis and C. africana in a collection of 287 strains originally identified as C. albicans isolated from an Argentinian hospital during 2013. Antifungal susceptibilities to fluconazole, clotrimazole, itraconazole, voriconazole, nystatin, amphotericin B and terbinafine were evaluated by using the CLSI M27-A3 and M27-S4 documents. Of the 287 isolates, 4 C. dubliniensis and one C. africana strains (1.39% and 0.35% prevalence, respectively) were identified. This is the first description of C. africana in Argentina and its identification was confirmed by sequencing the ITS2 region and the hwp1 gene. C. dubliniensis and C. africana strains showed very low MIC values for all the tested antifungals. Fluconazole-reduced-susceptibility and azole cross-resistance were observed in 3.55% and 1.41% of the C. albicans isolates, respectively. These results demonstrate that antifungal resistance is still a rare phenomenon in this kind of isolates.

  5. Prospective Multicenter Study of the Epidemiology, Molecular Identification, and Antifungal Susceptibility of Candida parapsilosis, Candida orthopsilosis, and Candida metapsilosis Isolated from Patients with Candidemia ▿

    PubMed Central

    Cantón, Emilia; Pemán, Javier; Quindós, Guillermo; Eraso, Elena; Miranda-Zapico, Ilargi; Álvarez, María; Merino, Paloma; Campos-Herrero, Isolina; Marco, Francesc; de la Pedrosa, Elia Gomez G.; Yagüe, Genoveva; Guna, Remedios; Rubio, Carmen; Miranda, Consuelo; Pazos, Carmen; Velasco, David

    2011-01-01

    A 13-month prospective multicenter study including 44 hospitals was carried out to evaluate the epidemiology of Candida parapsilosis complex candidemia in Spain. Susceptibility to amphotericin B, flucytosine, fluconazole, itraconazole, voriconazole, posaconazole, anidulafungin, caspofungin, and micafungin was tested by the microdilution colorimetric method. A total of 364 C. parapsilosis complex isolates were identified by molecular methods: C. parapsilosis (90.7%), Candida orthopsilosis (8.2%), and Candida metapsilosis (1.1%). Most candidemias (C. parapsilosis, 76.4%; C. orthopsilosis, 70.0%; C. metapsilosis, 100%) were observed in adults. No C. orthopsilosis or C. metapsilosis candidemias occurred in neonates. C. parapsilosis was most frequent in adult intensive care unit (28.8%), surgery (20.9%), and internal medicine (19.7%) departments; and C. orthopsilosis was most frequent in hematology (28.6%), pediatrics (12.0%), and neonatology (11.5%) departments. The geographic distribution of C. orthopsilosis and C. metapsilosis was not uniform. According to CLSI clinical breakpoints, all C. orthopsilosis and C. metapsilosis isolates were susceptible to the nine agents tested. Resistance (MICs > 1 mg/liter) was observed only in C. parapsilosis: amphotericin B, posaconazole, itraconazole, and caspofungin (0.3% each), anidulafungin (1.9%), and micafungin (2.5%). Applying the new species-specific fluconazole and echinocandin breakpoints, the rates of resistance to fluconazole for C. parapsilosis and C. orthopsilosis increased to 4.8% and 0.3%, respectively; conversely, for C. parapsilosis they shifted from 1.9 to 0.6% (anidulafungin) and from 2.5 to 0.6% (micafungin). Our study confirms the different prevalence of C. parapsilosis complex candidemia among age groups: neither C. orthopsilosis nor C. metapsilosis was isolated from neonates; interestingly, C. metapsilosis was isolated only from adults and the elderly. The disparity in antifungal susceptibility among species

  6. 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.

  7. Minimal inhibitory concentrations of lucknomycin, a new polyenic derivative, for Candida and Aspergillus spp.

    PubMed Central

    Martínez-Quesada, J; Torres-Rodriguez, J M; Rosés-Codinachs, M; Amaral-Olivera, M

    1983-01-01

    The minimal inhibitory concentrations (MICs) of lucknomycin, a new polyenic derivative, were determined for 101 clinical isolates of Candida, 38 clinical or environmental strains of Aspergillus fumigatus, and 30 isolates of A. niger. The most susceptible species were Candida albicans and Candida tropicalis (mean MIC, 0.4 micrograms/ml). Aspergillus spp. were less susceptible, with mean MICs of 0.60 micrograms/ml for Aspergillus niger and 9.2 micrograms/ml for Aspergillus fumigatus. PMID:6625552

  8. Effectiveness of disinfectants used in hemodialysis against both Candida orthopsilosis and C. parapsilosis sensu stricto biofilms.

    PubMed

    Pires, Regina Helena; da Silva, Julhiany de Fátima; Gomes Martins, Carlos Henrique; Fusco Almeida, Ana Marisa; Pienna Soares, Christiane; Soares Mendes-Giannini, Maria José

    2013-05-01

    Biofilms have been observed in the fluid pathways of hemodialysis machines. The impacts of four biocides used for the disinfection of hemodialysis systems were tested against Candida parapsilosis sensu stricto and Candida orthopsilosis biofilms generated by isolates obtained from a hydraulic circuit that were collected in a hemodialysis unit. Acetic acid was shown to be the most effective agent against Candida biofilms. Strategies for effective disinfection procedures used for hemodialysis systems should also seek to kill and inhibit biofilms.

  9. Circulating Candida antigens and antibodies: useful markers of candidemia.

    PubMed Central

    Gutiérrez, J; Maroto, C; Piédrola, G; Martín, E; Perez, J A

    1993-01-01

    To investigate the utility of the 48-kDa antigen from Candida albicans in its commercial form (Directigen; Becton Dickinson) and three other serodiagnostic methods (detection of one antigen by Pastorex Candida [Sanofi Diagnostics Pasteur] and detection of immunoglobulin G [IgG] and IgM antibodies to C. albicans blastoconidia [bioMerieux]) for diagnosis of invasive Candida infection, we conducted a prospective clinical trial among 10 patients with candidemia (group 1), 30 patients colonized by C. albicans (group 2), 20 patients with bacteremia (group 3), and 20 subjects without clinical or microbiological evidence of infection. The Directigen system was positive for at least one serum sample each from eight patients in group 1. In groups 2, 3, and 4, it was positive for only three patients. There was no reaction to the Pastorex system in any of the patients infected with or colonized by C. albicans or in the non-Candida-carrying controls. The IgG antibody concentration oscillated between 100 and 800 (mean, 510 +/- 268) IU/ml for the patients in group 1. In this group, eight patients had IgG antibody levels of > 400 IU/ml. The percentages of persons with IgG antibody levels of > 400 IU/ml in groups 2, 3, and 4 were 43.3, 0, and 0, respectively. Specific IgM antibody was present in all group 1 patients but not in those in groups 2, 3, and 4. The sensitivity and specificity of the Directigen test were 65 and 97.1%, respectively. For the Pastorex test, the sensitivity was 0%. The sensitivity of IgG antibodies was 80%, with a specificity of 81.4%, while the IgM antibodies were 100% specific and sensitive. Both the positive and negative predictive values of specific IgM antibodies appeared to be superior to those of the other three tests. PMID:8408589

  10. A case of Candida guilliermondii abortion in an Arab mare

    PubMed Central

    Stefanetti, Valentina; Marenzoni, Maria Luisa; Lepri, Elvio; Coletti, Mauro; Casagrande Proietti, Patrizia; Agnetti, Francesco; Crotti, Silvia; Pitzurra, Lucia; Del Sero, Andrea; Passamonti, Fabrizio

    2014-01-01

    Ascending infections of equine uterus frequently result in placentitis and abortions; most of these infections are bacterial and are less commonly due to fungi. This report describes an abortion case in an Arab mare due to Candida guilliermondii that was diagnosed via cytological, histological, cultural and biomolecular assays. The histological lesions found were severe necrotizing placentitis associated with fetal pneumonia. To our knowledge this is the first case of C. guilliermondii abortion reported in equine species. PMID:24707460

  11. Xylitol inhibits carcinogenic acetaldehyde production by Candida species.

    PubMed

    Uittamo, Johanna; Nieminen, Mikko T; Kaihovaara, Pertti; Bowyer, Paul; Salaspuro, Mikko; Rautemaa, Riina

    2011-10-15

    Acetaldehyde is a highly toxic and mutagenic product of alcohol fermentation and metabolism which has been classified as a Class I carcinogen for humans by the International Agency for Research on Cancer of the World Health Organisation (WHO). Many Candida species representing oral microbiota have been shown to be capable of marked acetaldehyde production. The aim of our study was to examine the effects of various sugar alcohols and sugars on microbial acetaldehyde production. The study hypothesis was that xylitol could reduce the amount of acetaldehyde produced by Candida. Laboratory and clinical isolates of seven Candida species were selected for the study. The isolates were incubated in 12 mM ethanol and 110 mM glucose, fructose or xylitol at 37°C for 30 min and the formed acetaldehyde was measured by gas chromatography. Xylitol significantly (p < 0.0001) reduced the amount of acetaldehyde produced from ethanol by 84%. In the absence of xylitol, the mean acetaldehyde production in ethanol incubation was 220.5 μM and in ethanol-xylitol incubation 32.8 μM. This was found to be mediated by inhibition of the alcohol dehydrogenase enzyme activity. Coincubation with glucose reduced the amount of produced acetaldehyde by 23% and coincubation with fructose by 29%. At concentrations that are representative of those found in the oral cavity during the intake of proprietary xylitol products, xylitol was found to reduce the production of carcinogenic acetaldehyde from ethanol by Candida below the mutagenic level of 40-100 μM.

  12. Looking into Candida albicans infection, host response, and antifungal strategies

    PubMed Central

    Wang, Yan

    2015-01-01

    Candida albicans, a commonly encountered fungal pathogen, causes diseases varying from superficial mucosal complaints to life-threatening systemic disorders. Among the virulence traits of C. albicans, yeast-to-hypha transition is most widely acknowledged. Host innate immunity to C. albicans critically requires pattern recognition receptors (PRRs), and defence against C. albicans infection is provided by an exquisite interplay between the innate and adaptive arms of the host immune system. PMID:25590793

  13. Looking into Candida albicans infection, host response, and antifungal strategies.

    PubMed

    Wang, Yan

    2015-01-01

    Candida albicans, a commonly encountered fungal pathogen, causes diseases varying from superficial mucosal complaints to life-threatening systemic disorders. Among the virulence traits of C. albicans, yeast-to-hypha transition is most widely acknowledged. Host innate immunity to C. albicans critically requires pattern recognition receptors (PRRs), and defence against C. albicans infection is provided by an exquisite interplay between the innate and adaptive arms of the host immune system.

  14. Evaluation of in vivo pathogenicity of Candida parapsilosis, Candida orthopsilosis, and Candida metapsilosis with different enzymatic profiles in a murine model of disseminated candidiasis.

    PubMed

    Treviño-Rangel, Rogelio de J; Rodríguez-Sánchez, Irám P; Elizondo-Zertuche, M; Martínez-Fierro, Margarita L; Garza-Veloz, Idalia; Romero-Díaz, Víktor J; González, José G; González, Gloria M

    2014-04-01

    Six isolates of the Candida parapsilosis complex with different enzymatic profiles were used to induce systemic infection in immunocompetent BALB/c mice. Fungal tissue burden was determined on days 2, 5, 10, and 15 post challenge. The highest fungal load irrespective of post-infection day was detected in the kidney, followed by the spleen, lung, and liver, with a tendency for the fungal burden to decrease by day 15 in all groups. Significant differences among the strains were not detected, suggesting that the three species of the "psilosis" group possess a similar pathogenic potential in disseminated candidiasis regardless of their enzymatic profiles.

  15. Polyketide Glycosides from Bionectria ochroleuca Inhibit Candida albicans Biofilm Formation

    PubMed Central

    2015-01-01

    One of the challenges presented by Candida infections is that many of the isolates encountered in the clinic produce biofilms, which can decrease these pathogens’ susceptibilities to standard-of-care antibiotic therapies. Inhibitors of fungal biofilm formation offer a potential solution to counteracting some of the problems associated with Candida infections. A screening campaign utilizing samples from our fungal extract library revealed that a Bionectria ochroleuca isolate cultured on Cheerios breakfast cereal produced metabolites that blocked the in vitro formation of Candida albicans biofilms. A scale-up culture of the fungus was undertaken using mycobags (also known as mushroom bags or spawn bags), which afforded four known [TMC-151s C–F (1–4)] and three new [bionectriols B–D (5–7)] polyketide glycosides. All seven metabolites exhibited potent biofilm inhibition against C. albicans SC5314, as well as exerted synergistic antifungal activities in combination with amphotericin B. In this report, we describe the structure determination of the new metabolites, as well as compare the secondary metabolome profiles of fungi grown in flasks and mycobags. These studies demonstrate that mycobags offer a useful alternative to flask-based cultures for the preparative production of fungal secondary metabolites. PMID:25302529

  16. Treatment of exogenous Candida endophthalmitis in rabbits with oral fluconazole.

    PubMed Central

    Park, S S; D'Amico, D J; Paton, B; Baker, A S

    1995-01-01

    We investigated the efficacy of oral fluconazole, alone or in combination with oral flucytosine (5FC), in treating Candida endophthalmitis using a rabbit model. Albino rabbits were infected with an intravitreal inoculation of 1,000 CFU of susceptible Candida albicans and randomized 5 days later to receive treatment with oral fluconazole alone (80 mg/kg of body weight per day), a combination of fluconazole and 5FC (100 mg/kg/12 h), or no treatment. The treatment effect was assessed at 2 and 4 weeks after therapy by funduscopy, quantitative vitreous culture, and histopathology. Intravitreal levels of fluconazole, 2 to 24 h after the first dose, were measured to be > 10 times the MIC of the drug for C. albicans. Among rabbits treated with fluconazole for 2 weeks, 67% had a > 90% reduction in fungal load (P < 0.05) and 33% were sterile. After 4 weeks, all had a > 99% reduction in fungal load (P < 0.05) and 75% were sterile (P = 0.01). This treatment effect was unchanged 4 weeks after discontinuation of fluconazole. Among rabbits treated with fluconazole and 5FC for 2 weeks, 67% died during therapy. Among the surviving rabbits, 75% had a > 90% reduction in fungal load (P < 0.05) and 25% were sterile. We conclude that oral fluconazole may be useful for treatment of Candida endophthalmitis. Addition of 5FC was associated with high toxicity and minimal additional antifungal effect in our rabbit model. PMID:7786003

  17. Rapid flow cytometric susceptibility testing of Candida albicans.

    PubMed Central

    Ramani, R; Ramani, A; Wong, S J

    1997-01-01

    A rapid flow cytometric assay for in vitro antifungal drug susceptibility testing was developed by adapting the proposed reference method for broth macrodilution testing of yeasts. Membrane permeability changes caused by the antifungal agent were measured by flow cytometry using propidium iodide, a nucleic acid-binding fluorochrome largely excluded by the intact cell membrane. We determined the in vitro susceptibility of 31 Candida albicans isolates and two quality control strains (Candida parapsilosis ATCC 22019 and Candida krusei ATCC 6258) to amphotericin B and fluconazole. Amphotericin B MICs ranged from 0.03 to 2.0 microg/ml, while fluconazole MICs ranged from 0.125 to 128 microg/ml. This method results in clear-cut endpoints that were reproducible. Four-hour incubation was required for fluconazole, whereas a 2-h incubation was sufficient for amphotericin B to provide MICs comparable to the reference macrodilution method developed by the National Committee for Clinical Laboratory Standards Subcommittee on Antifungal Susceptibility Tests. Results of these studies show that flow cytometry provides a rapid and sensitive in vitro method for antifungal susceptibility testing of C. albicans. PMID:9276410

  18. Ambroxol influences voriconazole resistance of Candida parapsilosis biofilm.

    PubMed

    Pulcrano, Giovanna; Panellis, Dimitrios; De Domenico, Giovanni; Rossano, Fabio; Catania, Maria Rosaria

    2012-06-01

    The ability to form biofilm on different surfaces is typical of most Candida species. Microscopic structure and genetic aspects of fungal biofilms have been the object of many studies because of very high resistance to antimycotic agents because of the scarce permeability of the external matrix and to the alterations in cell metabolism. In our study, 31 isolates of Candida parapsilosis, isolated from bloodstream infections, were tested for their ability to produce biofilm and were found to be good producers. The susceptibility to voriconazole, assayed by colorimetrical XTT assay, revealed a very elevated minimum inhibitory concentrations for sessile cells in comparison with planktonic ones. The addition of ambroxol, a mucolytic agent, increased the susceptibility of biofilm forming cells to voriconazole. Expression of the efflux pump genes CDR and MDR was analyzed in biofilms alone or treated with ambroxol, evidencing a role of ambroxol in the expression of genes involved in azole resistance mechanisms of C. parapsilosis biofilms. In conclusion, our data seem to encourage the use of different substances in combination with classical antimycotics, with the aim of finding a solution to the increasing problem of the resistance of biofilms formed on medical devices by nonalbicans Candida species.

  19. Genome structure and dynamics of the yeast pathogen Candida glabrata

    PubMed Central

    Ahmad, Khadija M; Kokošar, Janez; Guo, Xiaoxian; Gu, Zhenglong; Ishchuk, Olena P; Piškur, Jure

    2014-01-01

    The yeast pathogen Candida glabrata is the second most frequent cause of Candida infections. However, from the phylogenetic point of view, C. glabrata is much closer to Saccharomyces cerevisiae than to Candida albicans. Apparently, this yeast has relatively recently changed its life style and become a successful opportunistic pathogen. Recently, several C. glabrata sister species, among them clinical and environmental isolates, have had their genomes characterized. Also, hundreds of C. glabrata clinical isolates have been characterized for their genomes. These isolates display enormous genomic plasticity. The number and size of chromosomes vary drastically, as well as intra- and interchromosomal segmental duplications occur frequently. The observed genome alterations could affect phenotypic properties and thus help to adapt to the highly variable and harsh habitats this yeast finds in different human patients and their tissues. Further genome sequencing of pathogenic isolates will provide a valuable tool to understand the mechanisms behind genome dynamics and help to elucidate the genes contributing to the virulence potential. PMID:24528571

  20. Photodynamic therapy of oral Candida infection in a mouse model.

    PubMed

    Freire, Fernanda; Ferraresi, Cleber; Jorge, Antonio Olavo C; Hamblin, Michael R

    2016-06-01

    Species of the fungal genus Candida, can cause oral candidiasis especially in immunosuppressed patients. Many studies have investigated the use of photodynamic therapy (PDT) to kill fungi in vitro, but this approach has seldom been reported in animal models of infection. This study investigated the effects of PDT on Candida albicans as biofilms grown in vitro and also in an immunosuppressed mouse model of oral candidiasis infection. We used a luciferase-expressing strain that allowed non-invasive monitoring of the infection by bioluminescence imaging. The phenothiazinium salts, methylene blue (MB) and new methylene blue (NMB) were used as photosensitizers (PS), combined or not with potassium iodide (KI), and red laser (660nm) at four different light doses (10J, 20J, 40J and 60J). The best in vitro log reduction of CFU/ml on biofilm grown cells was: MB plus KI with 40J (2.31 log; p<0.001); and NMB without KI with 60J (1.77 log; p<0.001). These conditions were chosen for treating the in vivo model of oral Candida infection. After 5days of treatment the disease was practically eradicated, especially using MB plus KI with 40J. This study suggests that KI can potentiate PDT of fungal infection using MB (but not NMB) and could be a promising new approach for the treatment of oral candidiasis.

  1. Candida Virulence Properties and Adverse Clinical Outcomes in Neonatal Candidiasis

    PubMed Central

    Bliss, Joseph M.; Wong, Angela Y.; Bhak, Grace; Laforce-Nesbitt, Sonia S.; Taylor, Sarah; Tan, Sylvia; Stoll, Barbara J.; Higgins, Rosemary D.; Shankaran, Seetha; Benjamin, Daniel K.

    2012-01-01

    Objective To determine if premature infants with invasive Candida infection caused by strains with increased virulence properties have worse clinical outcomes than those infected with less virulent strains. Study design Clinical isolates were studied from 2 populations; premature infants colonized with Candida (commensal, n=27), and those with invasive candidiasis (n=81). Individual isolates of C. albicans and C. parapsilosis were tested for virulence in each of 3 assays: phenotypic switching, adhesion, and cytotoxicity. Invasive isolates were considered to have enhanced virulence if they measured more than 1 SD above the mean for the commensal isolates in at least 1 assay. Outcomes of patients with invasive isolates with enhanced virulence were compared with those with invasive isolates lacking enhanced virulence characteristics. Results 61% of invasive isolates of C. albicans and 42% of invasive isolates of C. parapsilosis had enhanced virulence. All C. albicans cerebrospinal fluid (CSF) isolates (n=6) and 90% of urine isolates (n=10) had enhanced virulence, compared with 48% of blood isolates (n=40). Infants with more virulent isolates were younger at the time of positive culture and had higher serum creatinine. Conclusions Individual isolates of Candida species vary in their virulence properties. Strains with higher virulence are associated with certain clinical outcomes. PMID:22504098

  2. Global Identification of Biofilm-Specific Proteolysis in Candida albicans

    PubMed Central

    Winter, Michael B.; Salcedo, Eugenia C.; Lohse, Matthew B.; Hartooni, Nairi; Gulati, Megha; Sanchez, Hiram; Takagi, Julie; Hube, Bernhard; Andes, David R.

    2016-01-01

    ABSTRACT Candida albicans is a fungal species that is part of the normal human microbiota and also an opportunistic pathogen capable of causing mucosal and systemic infections. C. albicans cells proliferate in a planktonic (suspension) state, but they also form biofilms, organized and tightly packed communities of cells attached to a solid surface. Biofilms colonize many niches of the human body and persist on implanted medical devices, where they are a major source of new C. albicans infections. Here, we used an unbiased and global substrate-profiling approach to discover proteolytic activities produced specifically by C. albicans biofilms, compared to planktonic cells, with the goal of identifying potential biofilm-specific diagnostic markers and targets for therapeutic intervention. This activity-based profiling approach, coupled with proteomics, identified Sap5 (Candidapepsin-5) and Sap6 (Candidapepsin-6) as major biofilm-specific proteases secreted by C. albicans. Fluorogenic peptide substrates with selectivity for Sap5 or Sap6 confirmed that their activities are highly upregulated in C. albicans biofilms; we also show that these activities are upregulated in other Candida clade pathogens. Deletion of the SAP5 and SAP6 genes in C. albicans compromised biofilm development in vitro in standard biofilm assays and in vivo in a rat central venous catheter biofilm model. This work establishes secreted proteolysis as a promising enzymatic marker and potential therapeutic target for Candida biofilm formation. PMID:27624133

  3. Characterisation of Candida within the Mycobiome/Microbiome of the Lower Respiratory Tract of ICU Patients

    PubMed Central

    Krause, Robert; Halwachs, Bettina; Thallinger, Gerhard G.; Klymiuk, Ingeborg; Gorkiewicz, Gregor; Hoenigl, Martin; Prattes, Jürgen; Valentin, Thomas; Heidrich, Katharina; Buzina, Walter; Salzer, Helmut J. F.; Rabensteiner, Jasmin; Prüller, Florian; Raggam, Reinhard B.; Meinitzer, Andreas; Moissl-Eichinger, Christine; Högenauer, Christoph; Quehenberger, Franz; Kashofer, Karl; Zollner-Schwetz, Ines

    2016-01-01

    Whether the presence of Candida spp. in lower respiratory tract (LRT) secretions is a marker of underlying disease, intensive care unit (ICU) treatment and antibiotic therapy or contributes to poor clinical outcome is unclear. We investigated healthy controls, patients with proposed risk factors for Candida growth in LRT (antibiotic therapy, ICU treatment with and without antibiotic therapy), ICU patients with pneumonia and antibiotic therapy and candidemic patients (for comparison of truly invasive and colonizing Candida spp.). Fungal patterns were determined by conventional culture based microbiology combined with molecular approaches (next generation sequencing, multilocus sequence typing) for description of fungal and concommitant bacterial microbiota in LRT, and host and fungal biomarkes were investigated. Admission to and treatment on ICUs shifted LRT fungal microbiota to Candida spp. dominated fungal profiles but antibiotic therapy did not. Compared to controls, Candida was part of fungal microbiota in LRT of ICU patients without pneumonia with and without antibiotic therapy (63% and 50% of total fungal genera) and of ICU patients with pneumonia with antibiotic therapy (73%) (p<0.05). No case of invasive candidiasis originating from Candida in the LRT was detected. There was no common bacterial microbiota profile associated or dissociated with Candida spp. in LRT. Colonizing and invasive Candida strains (from candidemic patients) did not match to certain clades withdrawing the presence of a particular pathogenic and invasive clade. The presence of Candida spp. in the LRT rather reflected rapidly occurring LRT dysbiosis driven by ICU related factors than was associated with invasive candidiasis. PMID:27206014

  4. Antifungal effects of phytocompounds on Candida species alone and in combination with fluconazole.

    PubMed

    Lu, Mengjiao; Li, Tao; Wan, Jianjian; Li, Xiuyun; Yuan, Lei; Sun, Shujuan

    2017-02-01

    Invasive fungal infections caused by Candida spp. remain the most predominant nosocomial fungal infections. Owing to the increased use of antifungal agents, resistance of Candida spp. to antimycotics has emerged frequently, especially to fluconazole (FLC). To cope with this issue, new efforts have been dedicated to discovering novel antimycotics or new agents that can enhance the susceptibility of Candida spp. to existing antimycotics. The secondary metabolites of plants represent a large library of compounds that are important sources for new drugs or compounds suitable for further modification. Research on the anti-Candida activities of phytocompounds has been carried out in recent years and the results showed that a series of phytocompounds have anti-Candida properties, such as phenylpropanoids, flavonoids, terpenoids and alkaloids. Among these phytocompounds, some displayed potent antifungal activity, with minimum inhibitory concentrations (MICs) of ≤8 µg/mL, and several compounds were even more effective against drug-resistant Candida spp. than FLC or itraconazole (e.g. honokiol, magnolol and shikonin). Interestingly, quite a few phytocompounds not only displayed anti-Candida activity alone but also synergised with FLC against Candida spp., even leading to a reversal of FLC resistance. This review focuses on summarising the anti-Candida activities of phytocompounds as well as the interactions of phytocompounds with FLC. In addition, we briefly overview the synergistic mechanisms and present the structure of the antimycotic phytocompounds. Hopefully, this analysis will provide insight into antifungal agent discovery and new approaches against antifungal drug resistance.

  5. Module Configuration

    DOEpatents

    Oweis, Salah; D'Ussel, Louis; Chagnon, Guy; Zuhowski, Michael; Sack, Tim; Laucournet, Gaullume; Jackson, Edward J.

    2002-06-04

    A stand alone battery module including: (a) a mechanical configuration; (b) a thermal management configuration; (c) an electrical connection configuration; and (d) an electronics configuration. Such a module is fully interchangeable in a battery pack assembly, mechanically, from the thermal management point of view, and electrically. With the same hardware, the module can accommodate different cell sizes and, therefore, can easily have different capacities. The module structure is designed to accommodate the electronics monitoring, protection, and printed wiring assembly boards (PWAs), as well as to allow airflow through the module. A plurality of modules may easily be connected together to form a battery pack. The parts of the module are designed to facilitate their manufacture and assembly.

  6. The MP65 gene is required for cell wall integrity, adherence to epithelial cells and biofilm formation in Candida albicans

    PubMed Central

    2011-01-01

    Background The MP65 gene of Candida albicans (orf19.1779) encodes a putative β-glucanase mannoprotein of 65 kDa, which plays a main role in a host-fungus relationship, morphogenesis and pathogenicity. In this study, we performed an extensive analysis of a mp65Δ mutant to assess the role of this protein in cell wall integrity, adherence to epithelial cells and biofilm formation. Results The mp65Δ mutant showed a high sensitivity to a range of cell wall-perturbing and degrading agents, especially Congo red, which induced morphological changes such as swelling, clumping and formation of hyphae. The mp65Δ mutant showed an activation of two MAPKs (Mkc1p and Cek1p), a high level of expression of two stress-related genes (DDR48 and SOD5), and a modulated expression of β-glucan epitopes, but no gross changes in cell wall polysaccharide composition. Interestingly, the mp65Δ mutant displayed a marked reduction in adhesion to BEC and Caco-2 cells and severe defects in biofilm formation when compared to the wild type. All of the mentioned properties were totally or partially recovered in a revertant strain, demonstrating the specificity of gene deletion. Conclusions We demonstrate that the MP65 gene of Candida albicans plays a significant role in maintaining cell wall integrity, as well as in adherence to epithelia and biofilm formation, which are major virulence attributes of this fungus. PMID:21575184

  7. Comparison of a randomly amplified polymorphic DNA (RAPD) analysis and ATB ID 32C system for identification of clinical isolates of different Candida species.

    PubMed

    Baires-Varguez, Laura; Cruz-García, Alejandro; Villa-Tanaka, Lourdes; Sánchez-García, Sergio; Gaitán-Cepeda, Luis Alberto; Sánchez-Vargas, Luis Octavio; Quindós, Guillermo; Hernández-Rodríguez, César

    2007-06-01

    The objective of this work was to compare the usefulness of a randomly amplified polymorphic DNA (RAPD) assay to that of the ATB ID32C kit (bioMérieux, France) for identification of different species of Candida isolated from clinical specimens. The RAPD-PCR patterns obtained with OPE-18 primer for identification of clinical isolates were consistent, and the different independent assays revealed reproduction of the band patterns. RAPD with the OPE-18 primer is a very specific and sensitive method for identification of Candida glabrata, Candida guilliermondii, Candida tropicalis, Candida pelliculosa, Candida albicans, Candida krusei, and Candida lusitaniae.

  8. Species distribution and virulence factors of Candida spp. isolated from the oral cavity of kidney transplant recipients in Brazil.

    PubMed

    Chaves, Guilherme Maranhão; Diniz, Mariana Guimarães; da Silva-Rocha, Walicyranison Plinio; de Souza, Luanda Bárbara Ferreira Canário; Gondim, Libia Augusta Maciel; Ferreira, Maria Angela Fernandes; Svidzinski, Terezinha Inez Estivalet; Milan, Eveline Pipolo

    2013-04-01

    Although yeasts belonging to the genus Candida are frequently seen as commensals in the oral cavity, they possess virulence attributes that contribute for pathogenicity. The aims of the present study were to study the prevalence of Candida spp. isolated from the oral cavity of renal transplant recipients and to analyze strains virulence factors. We isolated a total of 70 Candida strains from 111 transplant recipients, and Candida albicans was the most prevalent species (82.86 %). Oral candidiasis was diagnosed in 14.4 % kidney transplant patients, while 11 isolates (15.7 %) corresponded to non-Candida albicans Candida (NCAC) species. C. albicans adhered to a higher extension than NCAC strains. Some isolates of Candida tropicalis were markedly adherent to human buccal epithelial cells and highly biofilm-forming strains. Regarding proteinase activity, Candida orthopsilosis was more proteolytic than Candida metapsilosis. Candida glabrata and Candida dubliniensis showed very low ability to form biofilm on polystyrene microtiter plates. We have demonstrated here diverse peculiarities of different Candida species regarding the ability to express virulence factors. This study will contribute for the understanding of the natural history and pathogenesis of yeasts belonging to the genus Candida in the oral cavity of patients who were submitted to kidney transplant and are under immunosuppressive therapies.

  9. 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.

  10. Disk Diffusion Testing Using Candida sp. Colonies Taken Directly from CHROMagar Candida Medium May Decrease Time Required To Obtain Results

    PubMed Central

    Klevay, Michael; Ebinger, Alex; Diekema, Daniel; Messer, Shawn; Hollis, Richard; Pfaller, Michael

    2005-01-01

    We compared results of disk diffusion antifungal susceptibility testing from Candida sp. strains passaged on CHROMagar and on potato dextrose agar. The overall categorical agreements for fluconazole and voriconazole disk testing were 95% and 98% with 0% and 0.5% very major errors, respectively. Disk diffusion testing by the CLSI (formerly NCCLS) M44-A method can be performed accurately by taking inocula directly from CHROMagar. PMID:16000489

  11. The effect of silver nanoparticles and nystatin on mixed biofilms of Candida glabrata and Candida albicans on acrylic.

    PubMed

    Silva, Sónia; Pires, Priscila; Monteiro, Douglas R; Negri, Melyssa; Gorup, Luiz F; Camargo, Emerson R; Barbosa, Débora B; Oliveira, Rosário; Williams, David W; Henriques, Mariana; Azeredo, Joana

    2013-02-01

    The aim of this study was to compare biofilm formation by Candida glabrata and Candida albicans on acrylic, either individually or when combined (single and dual species) and then examine the antimicrobial effects of silver nanoparticles and nystatin on these biofilms. Candidal adhesion and biofilm assays were performed on acrylic surface in the presence of artificial saliva (AS) for 2 h and 48 h, respectively. Candida glabrata and C. albicans adherence was determined by the number of colony forming units (CFUs) recovered from the biofilms on CHROMagar(®) Candida. In addition, crystal violet (CV) staining was used as an indicator of biofilm biomass and to quantify biofilm formation ability. Pre-formed biofilms were treated either with silver nanoparticles or nystatin and the effect of these agents on the biofilms was evaluated after 24 h. Results showed that both species adhered to and formed biofilms on acrylic surfaces. A significantly (P < 0.05) higher number of CFUs was evident in C. glabrata biofilms compared with those formed by C. albicans. Comparing single and dual species biofilms, equivalent CFU numbers were evident for the individual species. Both silver nanoparticles and nystatin reduced biofilm biomass and the CFUs of single and dual species biofilms (P < 0.05). Silver nanoparticles had a significantly (P < 0.05) greater effect on reducing C. glabrata biofilm biomass compared with C. albicans. Similarly, nystatin was more effective in reducing the number of CFUs of dual species biofilms compared with those of single species (P < 0.05). In summary, C. glabrata and C. albicans can co-exist in biofilms without apparent antagonism, and both silver nanoparticles and nystatin exhibit inhibitory effects on biofilms of these species.

  12. Effect of Eugenol on Cell Surface Hydrophobicity, Adhesion, and Biofilm of Candida tropicalis and Candida dubliniensis Isolated from Oral Cavity of HIV-Infected Patients.

    PubMed

    de Paula, Suelen Balero; Bartelli, Thais Fernanda; Di Raimo, Vanessa; Santos, Jussevania Pereira; Morey, Alexandre Tadachi; Bosini, Marina Andrea; Nakamura, Celso Vataru; Yamauchi, Lucy Megumi; Yamada-Ogatta, Sueli Fumie

    2014-01-01

    Most Candida spp. infections are associated with biofilm formation on host surfaces. Cells within these communities display a phenotype resistant to antimicrobials and host defenses, so biofilm-associated infections are difficult to treat, representing a source of reinfections. The present study evaluated the effect of eugenol on the adherence properties and biofilm formation capacity of Candida dubliniensis and Candida tropicalis isolated from the oral cavity of HIV-infected patients. All isolates were able to form biofilms on different substrate surfaces. Eugenol showed inhibitory activity against planktonic and sessile cells of Candida spp. No metabolic activity in biofilm was detected after 24 h of treatment. Scanning electron microscopy demonstrated that eugenol drastically reduced the number of sessile cells on denture material surfaces. Most Candida species showed hydrophobic behavior and a significant difference in cell surface hydrophobicity was observed after exposure of planktonic cells to eugenol for 1 h. Eugenol also caused a significant reduction in adhesion of most Candida spp. to HEp-2 cells and to polystyrene. These findings corroborate the effectiveness of eugenol against Candida species other than C. albicans, reinforcing its potential as an antifungal applied to limit both the growth of planktonic cells and biofilm formation on different surfaces.

  13. 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

  14. Synergistic effect of amphotericin B and tyrosol on biofilm formed by Candida krusei and Candida tropicalis from intrauterine device users.

    PubMed

    Shanmughapriya, Santhanam; Sornakumari, Haridevvenkatesan; Lency, Arumugam; Kavitha, Senthil; Natarajaseenivasan, Kalimuthusamy

    2014-11-01

    The presence of intrauterine contraceptive devices (IUDs) provides a solid surface for attachment of microorganisms and an ideal niche for the biofilm to form and flourish. Vaginal candidiasis is often associated with the use of IUDs. Treatment of vaginal candidiasis that develops in connection with IUD use requires their immediate removal. Here, we present in vitro evidence to support the use of combination therapy to inhibit Candida biofilm. Twenty-three clinical Candida isolates (10 C. krusei and 13 C. tropicalis) recovered from endocervical swabs obtained from IUD and non-IUD users were assessed for biofilm-formation ability. The rate of isolation of Candida did not differ significantly among IUD and non-IUD users (P = 0.183), but the biofilm-formation ability of isolates differed significantly (P = 0.02). An in vitro biofilm model with the obtained isolates was subjected to treatment with amphotericin B, tyrosol, and a combination of amphotericin B and tyrosol. Inhibition of biofilm by amphotericin B or tyrosol was found to be concentration dependent, with 50% reduction (P < 0.05) at 4 mg/l and 80 μM, respectively. Hence, a combination effect of tyrosol and amphotericin B was studied. Interestingly, approximately 90% reduction in biofilm was observed with use of 80 μM tyrosol combined with 4 mg/l amphotericin B (P < 0.001). This represents a first step in establishing an appropriate antibiofilm therapy when yeasts are present.

  15. 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

  16. Oral Candida spp carriers: its prevalence in patients with type 2 Diabetes Mellitus*

    PubMed Central

    Martinez, Ramon Felipe Fernandez; Jaimes-Aveldañez, Alejandra; Hernández-Pérez, Francisco; Arenas, Roberto; Miguel, Guadalupe Fabián-San

    2013-01-01

    BACKGROUND: Prevalence of oral candidiasis in diabetic patients is 13.7-64%. Candida albicans was the most frequently isolated species (75-86.5%). OBJECTIVE: To obtain the prevalence of Candida carriers among patients with type 2 diabetes mellitus to identify the species of the yeast. Study design: It is an open, observational, descriptive, cross-sectional, and prospective study. METHODS: We included voluntary patients from the National Diabetes Marathon and performed a blood glucose measurement, sialometry test, Gram-stained exfoliative cytology, and culture on Sabouraud dextrose agar and CHROMagar Candida TM. Results were analyzed using descriptive statistics. RESULTS: We examined 141 patients (mean age 57 years): 103 women (73%) and 38 men (26.9%). Exfoliative cytology was positive in 32 cases (23 with oral lesions); 78 had oral lesions but no Candida (93.9%). Candida was isolated in 58 patients (41.1%), 21 (45.6 %) had blood glucose greater than 126 mg/dl, and 37 (38.9%) had less than 126 mg/dl. The most frequent species was C. albicans (82.7%). Forty-two Candida carriers had salivary flow greater than 20 mm (72.4%), and 16 (27.5%) had hyposalivation. Candida was isolated in 25 of 79 patients with dental prosthesis (31.6%), 9 of 15 were smokers (60%), and 22 of 71 had symptoms (30.9%). CONCLUSIONS: Prevalence of oral Candida carriers in patients with type 2 diabetes mellitus in Mexico was similar to that found in other countries; exfoliative cytology was effective in finding Candida; salivary flow rate, use of prosthesis, and presence of oral lesions and symptoms were similar in oral Candida carriers and negative patients. Most smokers were Candida carriers. PMID:23739717

  17. Module Evaluation

    DTIC Science & Technology

    2006-02-01

    various testing methodologies for the evaluation and characterization of Transmit /Receive (T/R) modules for phased array radars. Discussed are techniques...for characterizing T/R modules in transmit and receive modes under ideal and emulated operation environments. Further, techniques for life testing...characteristics of T/R modules developed during the early and mid 1980’s. Data provided shows the performance in terms of gain and phase for both transmit

  18. 40 CFR 180.1144 - Candida oleophila isolate I-182; exemption from the requirement of a tolerance.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Candida oleophila isolate I-182... RESIDUES IN FOOD Exemptions From Tolerances § 180.1144 Candida oleophila isolate I-182; exemption from the requirement of a tolerance. Candida oleophila isolate I-182, when used as a post-harvest biological...

  19. 40 CFR 180.1144 - Candida oleophila isolate I-182; exemption from the requirement of a tolerance.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 24 2011-07-01 2011-07-01 false Candida oleophila isolate I-182... RESIDUES IN FOOD Exemptions From Tolerances § 180.1144 Candida oleophila isolate I-182; exemption from the requirement of a tolerance. Candida oleophila isolate I-182, when used as a post-harvest biological...

  20. Assessment of Antifungal Activity of Bakuchiol on Oral-Associated Candida spp.

    PubMed Central

    Nordin, Mohd-Al-Faisal; Abdul Razak, Fathilah; Himratul-Aznita, Wan Harun

    2015-01-01

    Bakuchiol is an active component of Psoralea glandulosa and Psoralea corylifolia, used in traditional Chinese medicine. The study aimed at investigating the antifungal activity of bakuchiol on planktonic and biofilm forms of orally associated Candida species. The antifungal susceptibility testing was determined by the broth micro dilution technique. Growth kinetics and cell surface hydrophobicity (CSH) of Candida were measured to assess the inhibitory effect of bakuchiol on Candida planktonic cells. Biofilm biomass and cellular metabolic activity were quantitatively estimated by the crystal violet (CV) and the 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-5-[(phenylamino)carbonyl]-2H-tetrazolium hydroxide (XTT) assays. All Candida strains have been shown to be susceptible to bakuchiol with the MIC ranges from 12.5 to 100 μg/mL. Significant decrease in specific growth rates and viable counts demonstrates the inhibitory effect of bakuchiol on Candida planktonic cells. A brief exposure to bakuchiol also reduced CSH of Candida (P < 0.05), indicating altered surface properties of yeast cells towards hydrophobic interfaces. Biofilm biomass and cell metabolic activity were mostly decreased, except for C. glabrata (P = 0.29). The antifungal properties of bakuchiol on Candida species in this in vitro study may give insights into the application in therapeutic strategy against Candida infections. PMID:26633986

  1. Phenotypic variability and therapeutic implications of Candida species in patients with oral lichen planus.

    PubMed

    Arora, S; Verma, M; Gupta, S R; Urs, A B; Dhakad, M S; Kaur, R

    2016-01-01

    We investigated the prevalence and phenotypic variation of Candida species in oral lichen planus (OLP) and the therapeutic implications of our findings. Eighty patients with clinically and histopathologically confirmed cases of OLP (64 non-erosive, 16 erosive) and a control group of 80 healthy individuals with no predisposing factors for oral candidiasis were examined for evidence of Candida infection. Oral swabs and smears were obtained for cytology and culture. Identification, speciation and antifungal susceptibility tests of Candida isolates were performed using an automated microbial identification system. Fifty percent of erosive OLP cases, 28% of non-erosive cases and none of the controls showed evidence of Candida. Candida albicans was found predominantly in non-erosive OLP, while other Candida species were predominate in erosive OLP. Non-Candida albicans isolates (C. glabrata, C. krusei) were resistant to the commonly used antifungals, clotrimazole and fluconazole. Candida infection is common in cases of OLP. We recommend antifungal sensitivity testing prior to antifungal therapy for the erosive form of OLP.

  2. Fungal complications after Candida preservation fluid contamination in liver transplant recipients.

    PubMed

    Levesque, Eric; Paugam-Burtz, Catherine; Saliba, Faouzi; Khoy-Ear, Linda; Merle, Jean-Claude; Jung, Boris; Stecken, Laurent; Ferrandiere, Martine; Mihaila, Liliana; Botterel, Francoise

    2015-11-01

    Donor-derived fungal infections can be associated with severe complications in transplant recipients. Donor-derived candidiasis has been described in kidney transplant recipients where contamination of the preservation fluid (PF) was a commonly proposed source. In liver transplantation, these fungal infections have been less explored. The aim of this study was therefore to determine the incidence and clinical relevance of Candida contamination of preservation fluid in the context of liver transplantation. A 5-year (2008-2012) retrospective multicentre study involving six French liver transplantation centers was performed to determine the incidence of Candida PF contamination. Postoperative clinical features, outcomes in recipients, and risk factors for Candida-related complications of liver transplantation were studied. Candida sp. was isolated from 28 of 2107 preservation fluid samples (1.33%). Candida albicans was the most common yeast (n = 18, 64%). Twenty-two recipients (78.5%) received antifungal therapy (echinocandins in 68%) for 7-37 days. Eight patients developed yeast-related complications (28.6%) including hepatic artery aneurysms (n = 6) and Candida peritonitis (n = 2). The 1-year mortality rate among patients after a yeast-related complication was 62.5%. The incidence of Candida PF contamination was low, but was associated with dramatic postoperative complications and high mortality. Close radiological follow-up may enable early recognition of the arterial complications associated with PF contamination by Candida.

  3. Molecular Identification of Candida Species Isolated from Onychomycosis in Shanghai, China.

    PubMed

    Feng, Xiaobo; Ling, Bo; Yang, Xianwei; Liao, Wanqing; Pan, Weihua; Yao, Zhirong

    2015-12-01

    Candida is a common cause of onychomycosis, especially for fingernail onychomycosis. In this study, two simple PCR-based assays combined with the internal transcribed spacers sequencing were performed to reveal the prevalence of Candida species including emerging species in onychomycosis, and triazole antifungal susceptibility profiles for Candida species were also evaluated. Among 210 Candida strains isolated from onychomycosis, Candida parapsilosis was the most common species (54.3%), followed by C. albicans (23.3%) and C. metapsilosis (9.5%). However, C. metapsilosis became the second leading species in toenail onychomycosis and accounted for 19.5% of Candida isolates from toenail samples. C. nivariensis, an emerging species, was firstly recovered from a toenail sample. Other emerging species such as C. orthopsilosis, C. pararugosa and C. fabryi were also identified by molecular tools. C. metapsilosis isolates exhibited significantly higher fluconazole minimum inhibitory concentrations than those exhibited by C. parapsilosis and C. albicans (P < 0.001). This study provides insight into the prevalence, distribution and susceptibility profiles of Candida species including emerging Candida species in onychomycosis.

  4. Description of Martiniozyma gen. nov. and transfer of seven Candida species to Saturnispora as new combinations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    DNA sequence analysis has shown Candida abiesophila (NRRL Y-11514T, CBS 5366T) and Candida asiatica (NRRL Y-63747T, CBS 10863T) to be members of a small clade that is phylogenetically separate from other yeasts. In view of their isolation from neighboring genera, such as Pichia and Saturnispora, the...

  5. 21 CFR 184.1387 - Lactase enzyme preparation from Candida pseudotropicalis.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Lactase enzyme preparation from Candida... Specific Substances Affirmed as GRAS § 184.1387 Lactase enzyme preparation from Candida pseudotropicalis. (a) This enzyme preparation is derived from the nonpathogenic, nontoxicogenic yeast...

  6. 21 CFR 184.1387 - Lactase enzyme preparation from Candida pseudotropicalis.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Lactase enzyme preparation from Candida... GENERALLY RECOGNIZED AS SAFE Listing of Specific Substances Affirmed as GRAS § 184.1387 Lactase enzyme preparation from Candida pseudotropicalis. (a) This enzyme preparation is derived from the...

  7. 21 CFR 184.1387 - Lactase enzyme preparation from Candida pseudotropicalis.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Lactase enzyme preparation from Candida... GENERALLY RECOGNIZED AS SAFE Listing of Specific Substances Affirmed as GRAS § 184.1387 Lactase enzyme preparation from Candida pseudotropicalis. (a) This enzyme preparation is derived from the...

  8. 21 CFR 184.1387 - Lactase enzyme preparation from Candida pseudotropicalis.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Lactase enzyme preparation from Candida... GENERALLY RECOGNIZED AS SAFE Listing of Specific Substances Affirmed as GRAS § 184.1387 Lactase enzyme preparation from Candida pseudotropicalis. (a) This enzyme preparation is derived from the...

  9. 21 CFR 184.1387 - Lactase enzyme preparation from Candida pseudotropicalis.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Lactase enzyme preparation from Candida... GENERALLY RECOGNIZED AS SAFE Listing of Specific Substances Affirmed as GRAS § 184.1387 Lactase enzyme preparation from Candida pseudotropicalis. (a) This enzyme preparation is derived from the...

  10. Quantitative relationships of Candida albicans infections and dressing patterns in Nigerian women.

    PubMed Central

    Elegbe, I A; Elegbe, I

    1983-01-01

    Candida albicans colony counts were far higher in patients with vaginitis wearing tight fitting clothing than in patients wearing loose fitting clothing. In Ile-Ife, Nigeria, tight fitting dresses, woolen and corduroy jeans, coupled with nylon underwear, appear to create an environment favorable to Candida albicans colonization. PMID:6338749

  11. Quantitative relationships of Candida albicans infections and dressing patterns in Nigerian women.

    PubMed

    Elegbe, I A; Elegbe, I

    1983-04-01

    Candida albicans colony counts were far higher in patients with vaginitis wearing tight fitting clothing than in patients wearing loose fitting clothing. In Ile-Ife, Nigeria, tight fitting dresses, woolen and corduroy jeans, coupled with nylon underwear, appear to create an environment favorable to Candida albicans colonization.

  12. In vitro interactions between anidulafungin and nonsteroidal anti-inflammatory drugs on biofilms of Candida spp.

    PubMed

    Rosato, Antonio; Catalano, Alessia; Carocci, Alessia; Carrieri, Antonio; Carone, Addolorata; Caggiano, Giuseppina; Franchini, Carlo; Corbo, Filomena; Montagna, Maria Teresa

    2016-03-01

    Candida spp. are responsible for many biomaterial-related infections; they give rise to infective pathologies typically associated with biofilm formation. We recently reported that the echinocandin anidulafungin (ANF) showed a strong in vitro activity against both planktonic and biofilms cells. Herein, we report the antifungal activities of ANF alone and in association with some non-steroidal anti-inflammatory drugs (NSAIDs) against nine Candida strain biofilms: four Candida albicans, two Candida glabrata and three Candida guilliermondii. The activity of ANF was assessed using an in vitro microbiological model relevant for clinical practice. ANF proved oneself to be active against biofilms cells, and a clear-cut synergism was found against Candida species biofilms when ANF was used in combination with three NSAIDs: aspirin, diclofenac, ibuprofen. The positive synergism against Candida spp. of ANF in association with aspirin or the other NSAIDs proved to be a very effective antifungal treatment (FICI<0.5). These results may provide the starting point for new combination therapies of ANF with NSAIDs against Candida biofilm pathologies.

  13. Enteric Gram-negative bacilli suppress Candida biofilms on Foley urinary catheters.

    PubMed

    Samaranayake, Y H; Bandara, H M H N; Cheung, B P K; Yau, J Y Y; Yeung, S K W; Samaranayake, L P

    2014-01-01

    Mixed Candida-bacterial biofilms in urinary catheters are common in hospitalized patients. (i) The aims of this study were to evaluate, quantitatively and qualitatively, the in vitro development of mono- and dual-species biofilms (MSBs and DSBs) of Candida albicans and two enteric gram-negative bacilli (EGNB; Pseudomonas aeruginosa or Escherichia coli) on Foley catheter (FC) discs, (ii) to determine the biofilm growth in tryptic soy broth or glucose supplemented artificial urine (AU) and (iii) to assess the inhibitory effects of EGNB and their lipopolysaccharides (LPS) on Candida biofilm growth. The growth of MSBs and DSBs on FC discs was monitored by cell counts and SEM. The metabolic activity of LPS-treated Candida biofilms was determined by the XTT reduction assay. Candida albicans and EGNB demonstrated significant inter- and intra-species differences in biofilm growth on FC discs (p < 0.01). Pseudomonas aeruginosa suppressed Candida albicans significantly (p < 0.001) in DSBs. Compared with MSBs, DSB of EGNB in glucose supplemented AU demonstrated robust growth. Escherichia coli and its LPS, significantly suppressed Candida biofilm growth, compared with Pseudomonas aeruginosa and its LPS (p < 0.001). Candida albicans and EGNB colonization in FC is significantly increased in AU with glucose, and variably modified by Escherichia coli, Pseudomonas aeruginosa and their corresponding LPS.

  14. Effect of amphotericin B alone or in combination with rifampicin or clarithromycin against Candida species biofilms.

    PubMed

    Del Pozo, Jose L; Francés, María L; Hernáez, Silvia; Serrera, Alicia; Alonso, Marta; Rubio, Manuel F

    2011-09-01

    Effectiveness of amphotericin B alone or in combination with rifampicin or clarithromycin on the killing of Candida species biofilms was investigated in vitro. Amphotericin B was assayed at 0.005 to 10 mg/ml. Rifampin and clarithromycin were assayed at 10 mg/ml. We studied 7 Candida albicans, 3 Candida parapsilosis, 3 Candida glabrata, 3 Candida krusei and 2 Candida tropicalis strains. Biofilms were developed in 96-well, flat-bottomed microtiter plates for 48 hours. A synergistic effect between amphotericin B and clarithromycin was demonstrated against 66.6% of C. parapsilosis, 66.6% of C. glabrata, and 42.8% of C. albicans biofilms. A synergistic effect between amphotericin B and rifampin was demonstrated against 66.6% of C. parapsilosis, 42.8% of C. albicans, and 33.3% of C. glabrata biofilms. No synergistic effect was observed against C. krusei or C. tropicalis biofilms with any of the combinations. Rifampin or clarithromycin alone did not exert any effect on Candida species biofilms. Rifampin or clarithromycin combinations with amphotericin B might be of interest in the treatment of Candida biofilm-related infections.

  15. The Relation between Oral Candida Load and Bacterial Microbiome Profiles in Dutch Older Adults

    PubMed Central

    Kraneveld, Eefje A.; Buijs, Mark J.; Bonder, Marc J.; Visser, Marjolein; Keijser, Bart J. F.; Crielaard, Wim; Zaura, Egija

    2012-01-01

    Currently there are no evidence-based ecological measures for prevention of overgrowth and subsequent infection by fungi in the oral cavity. The aim of this study was to increase our knowledge on fungal–bacterial ecological interactions. Salivary Candida abundance of 82 Dutch adults aged 58–80 years was established relative to the bacterial load by quantitative PCR analysis of the Internal Transcribed (ITS) region (Candida) and 16S rDNA gene (bacteria). The salivary microbiome was assessed using barcoded pyrosequencing of the bacterial hypervariable regions V5–V7 of 16S rDNA. Sequencing data was preprocessed by denoising and chimera removal, clustered in Operational Taxonomic Units (OTUs) and assigned to taxonomy. Both OTU-based (PCA, diversity statistics) and phylogeny-based analyses (UniFrac, PCoA) were performed. Saliva of Dutch older adults contained 0–4 × 108 CFU/mL Candida with a median Candida load of 0.06%. With increased Candida load the diversity of the salivary microbiome decreased significantly (p<0.001). Increase in the Candida load correlated positively with class Bacilli, and negatively with class Fusobacteria, Flavobacteria, and Bacteroidia. Microbiomes with high Candida load were less diverse and had a distinct microbial composition towards dominance by saccharolytic and acidogenic bacteria - streptococci. The control of the acidification of the oral environment may be a potential preventive measure for Candida outgrowth that should be evaluated in longitudinal clinical intervention trials. PMID:22900048

  16. To Leave, or Not to Leave: That Is the Problem in "A Doll's House" and "Candida"

    ERIC Educational Resources Information Center

    Varghaiyan, Naghmeh

    2015-01-01

    This paper explores representation of "Woman Question" in Henrik Ibsen's "A Doll's House" and George Bernard Shaw's "Candida." The paper argues that unlike many studies that have read Candida and Nora as two disparate characters, they can be considered as the same "New Woman" represented only from different…

  17. High-Quality Draft Genome Sequence of Candida apicola NRRL Y-50540.

    PubMed

    Vega-Alvarado, Leticia; Gómez-Angulo, Jorge; Escalante-García, Zazil; Grande, Ricardo; Gschaedler-Mathis, Anne; Amaya-Delgado, Lorena; Sanchez-Flores, Alejandro; Arrizon, Javier

    2015-06-11

    Candida apicola, a highly osmotolerant ascomycetes yeast, produces sophorolipids (biosurfactants), membrane fatty acids, and enzymes of biotechnological interest. The genome obtained has a high-quality draft for this species and can be used as a reference to perform further analyses, such as differential gene expression in yeast from Candida genera.

  18. High-Quality Draft Genome Sequence of Candida apicola NRRL Y-50540

    PubMed Central

    Vega-Alvarado, Leticia; Gómez-Angulo, Jorge; Escalante-García, Zazil; Grande, Ricardo; Gschaedler-Mathis, Anne; Amaya-Delgado, Lorena

    2015-01-01

    Candida apicola, a highly osmotolerant ascomycetes yeast, produces sophorolipids (biosurfactants), membrane fatty acids, and enzymes of biotechnological interest. The genome obtained has a high-quality draft for this species and can be used as a reference to perform further analyses, such as differential gene expression in yeast from Candida genera. PMID:26067948

  19. Colonization by Candida in children with cancer, children with cystic fibrosis, and healthy controls.

    PubMed

    Gammelsrud, K W; Sandven, P; Høiby, E A; Sandvik, L; Brandtzaeg, P; Gaustad, P

    2011-12-01

    A longitudinal, prospective study was conducted intermittently in Norway, from 1999 to 2008, to investigate the Candida colonization rates and species distributions in the tonsillopharyngeal and faecal flora in: (i) children with cancer; (ii) children with cystic fibrosis (CF); and (iii) healthy children. The effect of antibiotic treatment on Candida colonization was also studied, and we looked for changes in antifungal susceptibility over time within each child and between the different groups of children. In total, 566 tonsillopharyngeal swabs and 545 faecal samples were collected from 45 children with cancer, 37 children with CF, and 71 healthy, age-matched controls. The overall colonization rate with Candida was not significantly higher in the two groups of children undergoing extensive treatment with broad-spectrum antibiotics than in healthy controls. Approximately one-third of the cancer patients had a total lack of Candida colonization or had only one Candida-positive sample, despite multiple samples being taken, treatment with broad-spectrum antibiotics, long hospital stays, and periods with neutropenia. Children with CF had the highest prevalence of Candida albicans. Amoxycillin, azithromycin, third-generation cephalosporins and oral vancomycin resulted in a significantly increased Candida colonization rate. Phenoxymethylpenicillin, second-generation cephalosporins, metronidazole, trimethoprim-sulphamethoxazole, ciprofloxacin, penicillinase-resistant penicillins and inhaled tobramycin or colistin showed minimal effects on the Candida colonization rate. We found no evidence of development of antifungal resistance over time.

  20. The quorum-sensing molecules farnesol/homoserine lactone and dodecanol operate via distinct modes of action in Candida albicans.

    PubMed

    Hall, Rebecca A; Turner, Kara J; Chaloupka, James; Cottier, Fabien; De Sordi, Luisa; Sanglard, Dominique; Levin, Lonny R; Buck, Jochen; Mühlschlegel, Fritz A

    2011-08-01

    Living as a commensal, Candida albicans must adapt and respond to environmental cues generated by the mammalian host and by microbes comprising the natural flora. These signals have opposing effects on C. albicans, with host cues promoting the yeast-to-hyphal transition and bacteria-derived quorum-sensing molecules inhibiting hyphal development. Hyphal development is regulated through modulation of the cyclic AMP (cAMP)/protein kinase A (PKA) signaling pathway, and it has been postulated that quorum-sensing molecules can affect filamentation by inhibiting the cAMP pathway. Here, we show that both farnesol and 3-oxo-C(12)-homoserine lactone, a quorum-sensing molecule secreted by Pseudomonas aeruginosa, block hyphal development by affecting cAMP signaling; they both directly inhibited the activity of the Candida adenylyl cyclase, Cyr1p. In contrast, the 12-carbon alcohol dodecanol appeared to modulate hyphal development and the cAMP signaling pathway without directly affecting the activity of Cyr1p. Instead, we show that dodecanol exerted its effects through a mechanism involving the C. albicans hyphal repressor, Sfl1p. Deletion of SFL1 did not affect the response to farnesol but did interfere with the response to dodecanol. Therefore, quorum sensing in C. albicans is mediated via multiple mechanisms of action. Interestingly, our experiments raise the possibility that the Burkholderia cenocepacia diffusible signal factor, BDSF, also mediates its effects via Sfl1p, suggesting that dodecanol's mode of action, but not farnesol or 3-oxo-C(12)-homoserine lactone, may be used by other quorum-sensing molecules.

  1. Candida bromeliacearum sp. nov. and Candida ubatubensis sp. nov., two yeast species isolated from the water tanks of Canistropsis seidelii (Bromeliaceae).

    PubMed

    Ruivo, Carla C C; Lachance, Marc-André; Rosa, Carlos A; Bacci, Maurício; Pagnocca, Fernando C

    2005-09-01

    Strains belonging to two novel yeast species, Candida bromeliacearum and Candida ubatubensis, were isolated from the bromeliad tank of Canistropsis seidelii (Bromeliaceae) in a sandy coastal plain (restinga) ecosystem site in an Atlantic rainforest of south-eastern Brazil. These species were genetically distinct from all other currently accepted ascomycetous yeasts, based on sequence divergence in the D1/D2 domains of the large-subunit rDNA and in the small-subunit rDNA. The species occupy basal positions in the Metschnikowiaceae clade. The type strains are Candida bromeliacearum UNESP 00-103(T) (=CBS 10002(T)=NRRL Y-27811(T)) and Candida ubatubensis UNESP 01-247R(T) (=CBS 10003(T)=NRRL Y-27812(T)).

  2. Molecular Identification and Antifungal Susceptibility Testing of Clinical Isolates of the Candida rugosa Species Complex and Proposal of the New Species Candida neorugosa

    PubMed Central

    Paredes, Katihuska; Sutton, Deanna A.; Cano, Josep; Fothergill, Annette W.; Lawhon, Sara D.; Zhang, Sean; Watkins, Jeffrey P.

    2012-01-01

    Candida rugosa is a poorly known fungal species occasionally involved in human infections. A molecular analysis of the sequences of the D1/D2 domains and the internal transcribed spacer (ITS) region of the ribosomal genes of 24 clinical isolates phenotypically identified as C. rugosa demonstrated that only 10 (41.6%) isolates belonged to that species. The other isolates were identified as Candida pararugosa (41.6%) and Candida pseudorugosa (8.3%). The remaining two isolates, from human and equine infections, respectively, were clearly different from the others and represent a new species proposed here as Candida neorugosa. The closest species by D1/D2 sequences was the type strain of C. rugosa, with only 92.3% similarity. C. neorugosa can also be differentiated from all other species of the C. rugosa complex by phenotypic features. The eight antifungal drugs tested showed high in vitro activity against the 24 isolates included in the study. PMID:22553236

  3. New Eugenol Glucoside-based Derivative Shows Fungistatic and Fungicidal Activity against Opportunistic Candida glabrata.

    PubMed

    de Souza, Thiago Belarmino; Brito, Keila Mercês de Oliveira; Silva, Naiara Chaves; Rocha, Raissa Prado; de Sousa, Grasiely Faria; Duarte, Lucienir Pains; Coelho, Luiz Felipe Leomil; Dias, Amanda Latércia Tranches; Veloso, Marcia Paranho; Carvalho, Diogo Teixeira; Dias, Danielle Ferreira

    2016-01-01

    A new series of glucosides modified in their saccharide units were synthesized, evaluated against Candida sp., and compared to prototype 1, an eugenol tetracetyl glucoside previously synthesized and shown to be active against Candida glabrata. Among the new glucosides, benzyl derivative 5 was the most promising, showing fungistatic activity at IC50 18.1 μm against Candida glabrata (threefold higher than fluconazole) and fungicidal activity with a low IC90 value of 36.2 μm. Moreover, the cytotoxic activity of compound 5 (CC50 : 580.9 μm), tested in peripheral blood mononuclear cells, suggests its potential as an agent to treat Candida glabrata infections, with a selectivity index of 32. The new eugenol glucoside 5 may be considered as a novel structural pattern in the development of new anti-Candida drugs.

  4. Itraconazole-resistant Candida auris with phospholipase, proteinase and hemolysin activity from a case of vulvovaginitis.

    PubMed

    Kumar, Dharmendra; Banerjee, Tuhina; Pratap, Chandra Bhan; Tilak, Ragini

    2015-04-15

    Since the emergence of pathogenic non-albicans Candida species, a number of new isolates have been added to the list. One such unusual species is Candida auris (C. auris), recently isolated and studied in few reports. In this study, a case of vulvovaginitis caused by Candida auris incidentally identified by molecular methods using internal transcribed spacer polymerase chain reaction (ITS PCR) is described. Antifungal susceptibility testing revealed the isolate to be resistant to itraconazole (MIC ≥ 2 µg/ml) and expressed important virulence factors including phospholipase, proteinase and hemolysin activity. The patient was successfully treated with oral fluconazole and did not have any invasive fungemia. Very few cases of this emerging pathogen have been reported. However, its isolation from clinical specimens reveals the significance of non-albicans candida species over C. albicans and the diversity of Candida spp causing infections.

  5. Production of virulence factors in Candida strains isolated from patients with denture stomatitis and control individuals.

    PubMed

    Pereira, Cristiane Aparecida; Domingues, Nádia; Araújo, Maria Izabel Daniel Santos Alves; Junqueira, Juliana Campos; Back-Brito, Graziella Nuernberg; Jorge, Antonio Olavo Cardoso

    2016-05-01

    The aim of this study was to evaluate the production of virulence factors in Candida isolates from the oral cavities of 50 patients with different degrees of denture stomatitis (DS, type I, II and III) and 50 individuals without signs of DS. We evaluated the enzymatic and hemolytic activities, the biofilm formation, and the cell surface hydrophobicity (CSH) in all isolates. Germ tube (GT) production was also evaluated in Candida albicans and Candida dubliniensis isolates. In C. albicans and C. dubliniensis the secretion of hemolysin and GT production was significantly different between isolates from patients with DS and individuals without DS. No significant difference was observed in the production of virulence factors by Candida glabrata isolates. Candida isolates expressed a wide range of virulence factors. However, in the majority of isolates from the type III lesions, the production of the virulence factors was higher than for the other groups.

  6. Synergistic Effects and Mechanisms of Budesonide in Combination with Fluconazole against Resistant Candida albicans

    PubMed Central

    Li, Xiuyun; Yu, Cuixiang; Huang, Xin; Sun, Shujuan

    2016-01-01

    Candida albicans is an important opportunistic pathogen, causing both superficial mucosal infections and life-threatening systemic diseases in the clinic. The emergence of drug resistance in Candida albicans has become a noteworthy phenomenon due to the extensive use of antifungal agents and the development of biofilms. This study showed that budesonide potentiates the antifungal effect of fluconazole against fluconazole-resistant Candida albicans strains both in vitro and in vivo. In addition, our results demonstrated, for the first time, that the combination of fluconazole and budesonide can reverse the resistance of Candida albicans by inhibiting the function of drug transporters, reducing the formation of biofilms, promoting apoptosis and inhibiting the activity of extracellular phospholipases. This is the first study implicating the effects and mechanisms of budesonide against Candida albicans alone or in combination with fluconazole, which may ultimately lead to the identification of new potential antifungal targets. PMID:28006028

  7. The effect of ultraviolet radiation on the pathogenesis of Candida albicans in mice

    SciTech Connect

    Denkins, Y.M.

    1991-01-01

    This dissertation addresses questions concerning the effects of UV radiation on the pathogenesis of opportunistic fungal pathogens such as Candida albicans. UV radiation decreased the survival of Candida-infected mice; however, no correlation was found between suppression of the delayed type hypersensitivity (DTH) response and the course of lethal infection. This suggested that DTH was not protective against lethal disease with this organism. UV radiation also changed the persistence of the organism in the internal organs. UV-irradiated, infected animals had increased numbers of Candida in their kidneys compared to non-irradiated mice. Sensitization prior to UV irradiation aided clearance of the organism from the kidneys of UV-irradiated mice. These data show that UV radiation suppresses cell-mediated immunity to Candida albicans in mice and increases mortality of Candida-infected mice. Moreover, the data suggest that an increase in environmental UV radiation could increase the severity of pathogenic infections.

  8. Rapid Identification of Candida Species and Other Clinically Important Yeast Species by Flow Cytometry†

    PubMed Central

    Page, Brent T.; Kurtzman, Cletus P.

    2005-01-01

    Two rapid diagnostic assays, utilizing two different Luminex flow cytometry methods, were developed for identification of clinically important ascomycetous yeast species. Direct hybridization and allele-specific primer extension methods were both successful in establishing a DNA-based assay that can rapidly and accurately identify Candida albicans, Candida krusei, Candida parapsilosis, Candida glabrata, and Candida tropicalis as well as other clinical species. The direct hybridization assay was designed to identify a total of 19 ascomycetous yeast species, and the allele-specific primer extension assay was designed to identify a total of 34 species. Probes were validated against 438 strains representing 303 species. From culture to identification, the allele-specific primer extension method takes 8 h and the direct hybridization method takes less than 5 h to complete. These assays represent comprehensive, rapid tests that are well suited for the clinical laboratory. PMID:16145099

  9. A Case Report of Penile Infection Caused by Fluconazole- and Terbinafine-Resistant Candida albicans.

    PubMed

    Hu, Yongxuan; Hu, Yanqing; Lu, Yan; Huang, Shiyun; Liu, Kangxing; Han, Xue; Mao, Zuhao; Wu, Zhong; Zhou, Xianyi

    2017-04-01

    Candida albicans is the most common pathogen that causes balanoposthitis. It often causes recurrence of symptoms probably due to its antifungal resistance. A significant number of balanitis Candida albicans isolates are resistant to azole and terbinafine antifungal agents in vitro. However, balanoposthitis caused by fluconazole- and terbinafine-resistant Candida albicans has rarely been reported. Here, we describe a case of a recurrent penile infection caused by fluconazole- and terbinafine-resistant Candida albicans, as well as the treatments administered to this patient. The isolate from the patient was tested for drug susceptibility in vitro. It was sensitive to itraconazole, voriconazole, clotrimazole and amphotericin B, but not to terbinafine and fluconazole. Thus, oral itraconazole was administrated to this patient with resistant Candida albicans penile infection. The symptoms were improved, and mycological examination result was negative. Follow-up treatment of this patient for 3 months showed no recurrence.

  10. [Candida infiltrations in the iris and lens during iritis and situation after sepsis].

    PubMed

    Kuerten, D; Fuest, M; Mazinani, B; Walter, P; Plange, N

    2017-01-31

    Intraocular Candida infections are overall rather rare; nevertheless they are often found as endogenous infections after Candida sepsis and can be sight-threatening. The most common manifestations are either a sole chorioretinitis or an endophthalmitis. Here we report the case of a 35-year-old man developing Candida infiltrations in the lens capsule and behind the iris after corticosteroid treatment of a presumed HLA-B27-positive iritis. The patient suffered from a life-threatening intensive care stay with positive Candida blood cultures earlier after intestinal perforation. With systemic intracameral and topical voriconazole, the infection was successfully treated. In patients with positive blood samples for Candida, topical and systemic corticosteroids should be given with care even months after the last positive blood cultures.

  11. [Detection of phospholipidolytic Candida albicans isolated from saliva of children with Down's syndrome].

    PubMed

    Ribeiro, Evandro L; Campos, C De Castro; Crespo, A M Costa; Castro, Jovirês S; Rocha, Frederico P; Alves, Marcella; Goulart, Mariella S; Cardoso, Cléver; Ferreira, Wesley; Naves, Plínio Lázaro; Soares, A José; Miranda, Simone R; Pimenta, Fabiana C

    2002-01-01

    The childhood is one of the most propitious period of the life to the occurrence of infection by yeasts of the genus Candida. In children with Down's syndrome, besides the predispose factors to bucal candidiasis; macroglossia, bucal muscular incompetence, frequent respiratory diseases, motor difficulty and immunologic deficit are mentioned as additional elements for this fungus disease. It was verified that the children attacked by this syndrome have much more strains of Candida than other children. The aim of this study was to detect the prevalence of phospholipase producer, Candida on the saliva of children with Down's syndrome. Candida albicans was the only identified specie of Candida. The phospholipase production was found in isolated strains from both of study and control. However, the isolated strains of the group of children with Down's syndrome have strongly present phospholipidolitic.

  12. Regulated proteolysis of Candida albicans Ras1 is involved in morphogenesis and quorum sensing regulation

    PubMed Central

    Piispanen, Amy; Grahl, Nora; Hollomon, Jeffrey M.; Hogan, Deborah A.

    2013-01-01

    Summary In Candida albicans, a fungal pathogen, the small G-protein Ras1 regulates many important behaviors including white-opaque switching, biofilm formation, and the induction and maintenance of hyphal growth. Like other Ras proteins, Ras1 is activated upon guanine triphosphate binding, and its activity is further modulated by post-translational lipid modifications. Here, we report that the levels of membrane-associated, full-length Ras1 were higher in hyphae than in yeast, and that yeast contained a shorter, soluble Ras1 species that resulted from cleavage. Deletion of the putative cleavage site led to more rapid induction of hyphal growth and delayed hypha-to-yeast transitions. The cleaved Ras1 species was less able to activate its effector, adenylate cyclase (Cyr1), unless tethered to the membrane by a heterologous membrane-targeting domain. Ras1 cleavage was repressed by cAMP-signaling, indicating the presence of a positive feedback loop in which Cyr1 and cAMP influence Ras1. The C. albicans quorum sensing molecule farnesol, which inhibits Cyr1 and represses filamentation, caused an increase in the fraction of Ras1 in the cleaved form, particularly in nascent yeast formed from hyphae. This newly recognized mode of Ras regulation may control C. albicans Ras1 activity in important ways. PMID:23692372

  13. Ubiquitin-like epitopes associated with Candida albicans cell surface receptors.

    PubMed Central

    Sepulveda, P; Lopez-Ribot, J L; Gozalbo, D; Cervera, A; Martinez, J P; Chaffin, W L

    1996-01-01

    We have recently reported the cloning of a Candida albicans polyubiquitin gene and the presence of ubiquitin in the cell wall of this fungus. The polyubiquitin cDNA clone was isolated because of its reactivity with antibodies generated against the candidal 37-kDa laminin-binding protein. In the present study, we have further investigated the relationship between ubiquitin and cell wall components displaying receptor-like activities, including the 37-kDa laminin receptor, the 58-kDa fibrinogen-binding mannoprotein, and the candidal C3d receptor. Two-dimensional electrophoretic analysis and immunoblot experiments with antibodies against ubiquitin and the individually purified receptor-like molecules confirmed that these cell surface components are ubiquitinated. In an enzyme-linked immunosorbent assay, polyclonal antisera to each receptor reacted with ubiquitin, thus demonstrating that the purified receptor preparations used as immunogens contained ubiquitin-like epitopes. It is proposed that ubiquitin may play a role in modulating the activity of these receptors and in the interaction of C. albicans cells with host structures. PMID:8926122

  14. Levorotatory carbohydrates and xylitol subdue Streptococcus mutans and Candida albicans adhesion and biofilm formation.

    PubMed

    Brambilla, Eugenio; Ionescu, Andrei C; Cazzaniga, Gloria; Ottobelli, Marco; Samaranayake, Lakshman P

    2016-05-01

    Dietary carbohydrates and polyols affect the microbial colonization of oral surfaces by modulating adhesion and biofilm formation. The aim of this study was to evaluate the influence of a select group of l-carbohydrates and polyols on either Streptococcus mutans or Candida albicans adhesion and biofilm formation in vitro. S. mutans or C. albicans suspensions were inoculated on polystyrene substrata in the presence of Tryptic soy broth containing 5% of the following compounds: d-glucose, d-mannose, l-glucose, l-mannose, d- and l-glucose (raceme), d- and l-mannose (raceme), l-glucose and l-mannose, sorbitol, mannitol, and xylitol. Microbial adhesion (2 h) and biofilm formation (24 h) were evaluated using MTT-test and Scanning Electron Microscopy (SEM). Xylitol and l-carbohydrates induced the lowest adhesion and biofilm formation in both the tested species, while sorbitol and mannitol did not promote C. albicans biofilm formation. Higher adhesion and biofilm formation was noted in both organisms in the presence of d-carbohydrates relative to their l-carbohydrate counterparts. These results elucidate, hitherto undescribed, interactions of the individually tested strains with l- and d-carbohydrates, and how they impact fungal and bacterial colonization. In translational terms, our data raise the possibility of using l-form of carbohydrates and xylitol for dietary control of oral plaque biofilms.

  15. Activation of HIF-1α and LL-37 by commensal bacteria inhibits Candida albicans colonization.

    PubMed

    Fan, Di; Coughlin, Laura A; Neubauer, Megan M; Kim, Jiwoong; Kim, Min Soo; Zhan, Xiaowei; Simms-Waldrip, Tiffany R; Xie, Yang; Hooper, Lora V; Koh, Andrew Y

    2015-07-01

    Candida albicans colonization is required for invasive disease. Unlike humans, adult mice with mature intact gut microbiota are resistant to C. albicans gastrointestinal (GI) colonization, but the factors that promote C. albicans colonization resistance are unknown. Here we demonstrate that commensal anaerobic bacteria-specifically clostridial Firmicutes (clusters IV and XIVa) and Bacteroidetes-are critical for maintaining C. albicans colonization resistance in mice. Using Bacteroides thetaiotamicron as a model organism, we find that hypoxia-inducible factor-1α (HIF-1α), a transcription factor important for activating innate immune effectors, and the antimicrobial peptide LL-37 (CRAMP in mice) are key determinants of C. albicans colonization resistance. Although antibiotic treatment enables C. albicans colonization, pharmacologic activation of colonic Hif1a induces CRAMP expression and results in a significant reduction of C. albicans GI colonization and a 50% decrease in mortality from invasive disease. In the setting of antibiotics, Hif1a and Camp (which encodes CRAMP) are required for B. thetaiotamicron-induced protection against C. albicans colonization of the gut. Thus, modulating C. albicans GI colonization by activation of gut mucosal immune effectors may represent a novel therapeutic approach for preventing invasive fungal disease in humans.

  16. NADPH Oxidase-Driven Phagocyte Recruitment Controls Candida albicans Filamentous Growth and Prevents Mortality

    PubMed Central

    Brothers, Kimberly M.; Gratacap, Remi L.; Barker, Sarah E.; Newman, Zachary R.; Norum, Ashley; Wheeler, Robert T.

    2013-01-01

    Candida albicans is a human commensal and clinically important fungal pathogen that grows as both yeast and hyphal forms during human, mouse and zebrafish infection. Reactive oxygen species (ROS) produced by NADPH oxidases play diverse roles in immunity, including their long-appreciated function as microbicidal oxidants. Here we demonstrate a non-traditional mechanistic role of NADPH oxidase in promoting phagocyte chemotaxis and intracellular containment of fungi to limit filamentous growth. We exploit the transparent zebrafish model to show that failed NADPH oxidase-dependent phagocyte recruitment to C. albicans in the first four hours post-infection permits fungi to germinate extracellularly and kill the host. We combine chemical and genetic tools with high-resolution time-lapse microscopy to implicate both phagocyte oxidase and dual-specific oxidase in recruitment, suggesting that both myeloid and non-myeloid cells promote chemotaxis. We show that early non-invasive imaging provides a robust tool for prognosis, strongly connecting effective early immune response with survival. Finally, we demonstrate a new role of a key regulator of the yeast-to-hyphal switching program in phagocyte-mediated containment, suggesting that there are species-specific methods for modulation of NADPH oxidase-independent immune responses. These novel links between ROS-driven chemotaxis and fungal dimorphism expand our view of a key host defense mechanism and have important implications for pathogenesis. PMID:24098114

  17. Environmental pH influences Candida albicans biofilms regarding its structure, virulence and susceptibility to fluconazole.

    PubMed

    de Vasconcellos, Andréa Araújo; Gonçalves, Letícia Machado; Del Bel Cury, Altair Antoninha; da Silva, Wander José

    2014-01-01

    Candida albicans colonizes sites with different environmental pH. However, it is unclear how these conditions can interfere on biofilms. This study aimed to evaluate the influence of environmental pH on behavior of C. albicans regarding its structure, virulence and susceptibility to fluconazole (FLZ). Minimal inhibitory concentration, minimal fungicidal concentration and time kill were used to evaluate the susceptibility to FLZ in planktonic cells under three pH values (4.0, 5.5, 7.0). These pH values were used for biofilms analysis. C. albicans ATCC 90028 was developed on poly(methlymethacrylate) resin for 48 h. Then, 2.56 μg/mL of FLZ was added to experimental groups for 24 h, and biofilms were analyzed by cell quantification, bioactivity, secretion of proteinases and phospholipases and structure. All data were analyzed by two-way ANOVA, followed by Tukey's test (α = 0.05). For planktonic cells, changes in environmental pH decreased the susceptibility to FLZ. C. albicans biofilms developed at pH 5.5 showed higher cell counts, bioactivity, bio-volume, average thickness and roughness coefficient (p < 0.05). In contrast, the presence of FLZ at pH 4.0 did not influence the structural parameters (p > 0.05), but increased secretion of proteinase and phospholipase (p < 0.05). Within the conditions studied, it was shown that environmental pH modulates the structure, virulence and susceptibility of C. albicans to FLZ.

  18. Commensal Protection of Staphylococcus aureus against Antimicrobials by Candida albicans Biofilm Matrix

    PubMed Central

    Kong, Eric F.; Tsui, Christina; Kucharíková, Sona; Andes, David

    2016-01-01

    ABSTRACT Biofilm-associated polymicrobial infections, particularly those involving fungi and bacteria, are responsible for significant morbidity and mortality and tend to be challenging to treat. Candida albicans and Staphylococcus aureus specifically are considered leading opportunistic fungal and bacterial pathogens, respectively, mainly due to their ability to form biofilms on catheters and indwelling medical devices. However, the impact of mixed-species biofilm growth on therapy remains largely understudied. In this study, we investigated the influence of C. albicans secreted cell wall polysaccharides on the response of S. aureus to antibacterial agents in biofilm. Results demonstrated significantly enhanced tolerance for S. aureus to drugs in the presence of C. albicans or its secreted cell wall polysaccharide material. Fluorescence confocal time-lapse microscopy revealed impairment of drug diffusion through the mixed biofilm matrix. Using C. albicans mutant strains with modulated cell wall polysaccharide expression, exogenous supplementation, and enzymatic degradation, the C. albicans-secreted β-1,3-glucan cell wall component was identified as the key matrix constituent providing the bacteria with enhanced drug tolerance. Further, antibody labeling demonstrated rapid coating of the bacteria by the C. albicans matrix material. Importantly, via its effect on the fungal biofilm matrix, the antifungal caspofungin sensitized the bacteria to the drugs. Understanding such symbiotic interactions with clinical relevance between microbial species in biofilms will greatly aid in overcoming the limitations of current therapies and in defining potential new targets for treating polymicrobial infections. PMID:27729510

  19. Anaerobic bacteria grow within Candida albicans biofilms and induce biofilm formation in suspension cultures.

    PubMed

    Fox, Emily P; Cowley, Elise S; Nobile, Clarissa J; Hartooni, Nairi; Newman, Dianne K; Johnson, Alexander D

    2014-10-20

    The human microbiome contains diverse microorganisms, which share and compete for the same environmental niches. A major microbial growth form in the human body is the biofilm state, where tightly packed bacterial, archaeal, and fungal cells must cooperate and/or compete for resources in order to survive. We examined mixed biofilms composed of the major fungal species of the gut microbiome, Candida albicans, and each of five prevalent bacterial gastrointestinal inhabitants: Bacteroides fragilis, Clostridium perfringens, Escherichia coli, Klebsiella pneumoniae, and Enterococcus faecalis. We observed that biofilms formed by C. albicans provide a hypoxic microenvironment that supports the growth of two anaerobic bacteria, even when cultured in ambient oxic conditions that are normally toxic to the bacteria. We also found that coculture with bacteria in biofilms induces massive gene expression changes in C. albicans, including upregulation of WOR1, which encodes a transcription regulator that controls a phenotypic switch in C. albicans, from the "white" cell type to the "opaque" cell type. Finally, we observed that in suspension cultures, C. perfringens induces aggregation of C. albicans into "mini-biofilms," which allow C. perfringens cells to survive in a normally toxic environment. This work indicates that bacteria and C. albicans interactions modulate the local chemistry of their environment in multiple ways to create niches favorable to their growth and survival.

  20. Sequence of the lid affects activity and specificity of Candida rugosa lipase isoenzymes.

    PubMed

    Brocca, Stefania; Secundo, Francesco; Ossola, Mattia; Alberghina, Lilia; Carrea, Giacomo; Lotti, Marina

    2003-10-01

    The fungus Candida rugosa produces multiple lipase isoenzymes (CRLs) with distinct differences in substrate specificity, in particular with regard to selectivity toward the fatty acyl chain length. Moreover, isoform CRL3 displays high activity towards cholesterol esters. Lipase isoenzymes share over 80% sequence identity but diverge in the sequence of the lid, a mobile loop that modulates access to the active site. In the active enzyme conformation, the open lid participates in the substrate-binding site and contributes to substrate recognition. To address the role of the lid in CRL activity and specificity, we substituted the lid sequences from isoenzymes CRL3 and CRL4 in recombinant rCRL1, thus obtaining enzymes differing only in this stretch of residues. Swapping the CRL3 lid was sufficient to confer to CRL1 cholesterol esterase activity. On the other hand, a specific shift in the chain-length specificity was not observed. Chimeric proteins displayed different sensitivity to detergents in the reaction medium.

  1. Characterization of Candida isolates from pediatric burn patients.

    PubMed Central

    Neely, A N; Odds, F C; Basatia, B K; Holder, I A

    1988-01-01

    To provide more detailed information about Candida epidemiology and pathogenesis in pediatric burn patients, Candida isolates from 113 patients collected over 3 years were identified at the species level and the serotypes and biotypes of the C. albicans isolates were determined. A total of 85% of the patients were colonized or infected by C. albicans, 18% by C. tropicalis, and 11% by C. parapsilosis. Although colonization or infection often was found at multiple sites and times, 87% of the patients were colonized or infected by only one Candida species or strain; the other 13% showed multiple colonizations or infections, some of which occurred simultaneously at the same site. C. albicans biotyping determined the tolerance of the isolates to pH (pH 1.4) and salt; flucytosine, borate, and safranine resistance; and ability to produce proteinase and assimilate urea, sorbose, and citrate; results are expressed as three-digit numbers. For isolates from three different anatomical sites, the distribution of the nine biotype characteristics was similar in all cases but one. Significantly more fecal than wound or throat isolates were resistant to safranine. Sixty-four different serotype-biotype combinations were found in the 96 patients with C. albicans infections or colonizations. Twenty-nine percent of all C. albicans isolates had the partial biotype -57, while 20 of the 96 patients had specifically serotype B, biotype 557 colonizations or infections. Eleven patients had the B557 infection when admitted; nine patients acquired the yeast in-house. Thirty percent of the C. albicans isolated from 23 adult patients at a nearby hospital also showed the -57 biotype pattern, suggesting that C. albicans isolates expressing this biotype are either extremely prevalent in nature or are more virulent than other C. albicans isolates. PMID:3053771

  2. The Pathogen Candida albicans Hijacks Pyroptosis for Escape from Macrophages

    PubMed Central

    Uwamahoro, Nathalie; Verma-Gaur, Jiyoti; Shen, Hsin-Hui; Qu, Yue; Lewis, Rowena; Lu, Jingxiong; Bambery, Keith; Masters, Seth L.; Vince, James E.; Naderer, Thomas; Traven, Ana

    2014-01-01

    ABSTRACT The fungal pathogen Candida albicans causes macrophage death and escapes, but the molecular mechanisms remained unknown. Here we used live-cell imaging to monitor the interaction of C. albicans with macrophages and show that C. albicans kills macrophages in two temporally and mechanistically distinct phases. Early upon phagocytosis, C. albicans triggers pyroptosis, a proinflammatory macrophage death. Pyroptosis is controlled by the developmental yeast-to-hypha transition of Candida. When pyroptosis is inactivated, wild-type C. albicans hyphae cause significantly less macrophage killing for up to 8 h postphagocytosis. After the first 8 h, a second macrophage-killing phase is initiated. This second phase depends on robust hyphal formation but is mechanistically distinct from pyroptosis. The transcriptional regulator Mediator is necessary for morphogenesis of C. albicans in macrophages and the establishment of the wild-type surface architecture of hyphae that together mediate activation of macrophage cell death. Our data suggest that the defects of the Mediator mutants in causing macrophage death are caused, at least in part, by reduced activation of pyroptosis. A Mediator mutant that forms hyphae of apparently wild-type morphology but is defective in triggering early macrophage death shows a breakdown of cell surface architecture and reduced exposed 1,3 β-glucan in hyphae. Our report shows how Candida uses host and pathogen pathways for macrophage killing. The current model of mechanical piercing of macrophages by C. albicans hyphae should be revised to include activation of pyroptosis by hyphae as an important mechanism mediating macrophage cell death upon C. albicans infection. PMID:24667705

  3. Diagnostic value of anti-Candida enolase antibodies.

    PubMed Central

    van Deventer, A J; van Vliet, H J; Hop, W C; Goessens, W H

    1994-01-01

    An immunodominant antigen with enolase enzyme activity was purified and used for the development of an assay to detect antibodies directed against this antigen in sera from patients with either invasive candidiasis or Candida colonization. The Au enzyme-linked immunosorbent assay established with the Candida enolase antigen was able to discriminate significantly between invasive candidiasis and colonization in both immunocompetent and immunodeficient groups of patients. The test had a sensitivity of 50% and a specificity of 86% in the immunocompetent patient group. In the immunodeficient patient group, a sensitivity of 53% and a specificity of 78% were established. Antibody levels determined by a counterimmunoelectrophoresis assay with the same set of sera resulted in a better sensitivity for sera from the immunocompetent patient group but a lower specificity, i.e., 80 and 29%, respectively. The counterimmunoelectrophoresis assay of sera from the immunodeficient patient group was not able to discriminate significantly between invasive candidiasis and colonization. With the use of more serum from each patient, the sensitivity of the antibody detection assays increased, while the specificity was maintained. The increase, however, was not statistically significant. Combining the results of the antibody assays with antigen titers obtained by the Cand-Tec assay did not improve the predictive value with respect to invasive candidiasis, as determined by multivariance regression analysis. Furthermore, it was demonstrated by performance of Western blots (immunoblots) that sera from patients as well as a rabbit antiserum cross-reacted with the Candida enolase and baker's yeast enolase enzyme. However, by tandem crossed immunoelectrophoresis it was demonstrated that the antibodies were directed toward different epitopes of the antigen. Images PMID:8126174

  4. 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

  5. Evaluation of matrix-assisted laser desorption ionization-time-of-flight mass spectrometry to differentiate between Candida albicans and Candida dubliniensis.

    PubMed

    Roberts, Amity L; Alelew, Aqilah; Iwen, Peter C

    2016-05-01

    Matrix-assisted laser desorption ionization-time-of-flight mass spectrometry (MALDI-TOF-MS) analysis in conjunction with the direct formic acid (FA) sample processing method was evaluated for the ability to differentiate the closely related species of Candida albicans and Candida dubliniensis. The results showed that MALDI-TOF-MS, using the direct FA method, was reliable to differentiate between these species.

  6. Candida albicans specializations for iron homeostasis: from commensalism to virulence.

    PubMed

    Noble, Suzanne M

    2013-12-01

    Candida albicans is a fungal commensal-pathogen that persistently associates with its mammalian hosts. Between the commensal and pathogenic lifestyles, this microorganism inhabits host niches that differ markedly in the levels of bioavailable iron. A number of recent studies have exposed C. albicans specializations for acquiring iron from specific host molecules in regions where iron is scarce, while also defending against iron-related toxicity in regions where iron occurs in surfeit. Together, these results point to a central role for iron homeostasis in the evolution of this important human pathogen.

  7. [Molecular identification of Candida lusitaniae in lower respiratory tract infection].

    PubMed

    Espinosa, Israel Martínez; Ibarra, Misael González; Torres Guerrero, Haydee K

    2014-01-01

    Candida lusitaniae is a yeast that has emerged as a low frequency nosocomial pathogen in deep infections. Although it usually shows in vitro susceptibility to all antifungal agents, in vivo resistance to amphotericin B has been observed in several clinical cases. Therefore, its early identification in the course of therapy is important. We report the isolation of C. lusitaniae as an etiologic agent of a lower respiratory tract infection in a male patient. Urine and sputum cultures were negative for bacteria and positive for this yeast. Isolates were identified by routine phenotypic methods and confirmed by sequencing and restriction fragment length polymorphism analysis of PCR internal spacer of ribosomal DNA.

  8. [Candida laryngitis and HIV infection: description of 4 cases].

    PubMed

    Roig, P; Carrasco, R; Salavert, M; Navarro, V; Guix, J; Nieto, A; Bernacer, B

    1992-10-01

    Candidiasic laryngitis is a very rare Candida spp infection of mucosa, appearing typically in immunosuppressed patients, mainly in patients with neoplasia, and, recently, in patients with Human Immunodeficiency Virus (VIH) infection. We present four cases of candidiasic laryngitis and HIV infection, as well as the clinical description and evolution of said cases after treatment with fluconazole. We review, as well, the cases published on the scientific literature. We maintain that in each HIV infected patient, with or without oral candidiasis, who shows dysphonia, candidiasic laryngitis should be ruled out.

  9. Candida albicans biofilms: building a heterogeneous, drug-tolerant environment.

    PubMed

    Bonhomme, Julie; d'Enfert, Christophe

    2013-08-01

    Fungi are able to form biofilms on medical implants, causing serious infections. A better understanding of fungal biofilm formation is necessary to develop tools for detection or prevention and to identify new antifungal strategies. This review explores recent advances in the characterization at the molecular level of fungal biofilms, especially those formed by the yeast Candida albicans: the identification of complex transcriptional networks that control their formation; the pivotal role of the extracellular matrix in biofilm antifungal tolerance; and the knowledge gained on the physiology of biofilm cells and heterogeneity within these communities. These findings may help develop new, targeted therapeutic strategies.

  10. The pathogen Candida albicans hijacks pyroptosis for escape from macrophages.

    PubMed

    Uwamahoro, Nathalie; Verma-Gaur, Jiyoti; Shen, Hsin-Hui; Qu, Yue; Lewis, Rowena; Lu, Jingxiong; Bambery, Keith; Masters, Seth L; Vince, James E; Naderer, Thomas; Traven, Ana

    2014-03-25

    The fungal pathogen Candida albicans causes macrophage death and escapes, but the molecular mechanisms remained unknown. Here we used live-cell imaging to monitor the interaction of C. albicans with macrophages and show that C. albicans kills macrophages in two temporally and mechanistically distinct phases. Early upon phagocytosis, C. albicans triggers pyroptosis, a proinflammatory macrophage death. Pyroptosis is controlled by the developmental yeast-to-hypha transition of Candida. When pyroptosis is inactivated, wild-type C. albicans hyphae cause significantly less macrophage killing for up to 8 h postphagocytosis. After the first 8 h, a second macrophage-killing phase is initiated. This second phase depends on robust hyphal formation but is mechanistically distinct from pyroptosis. The transcriptional regulator Mediator is necessary for morphogenesis of C. albicans in macrophages and the establishment of the wild-type surface architecture of hyphae that together mediate activation of macrophage cell death. Our data suggest that the defects of the Mediator mutants in causing macrophage death are caused, at least in part, by reduced activation of pyroptosis. A Mediator mutant that forms hyphae of apparently wild-type morphology but is defective in triggering early macrophage death shows a breakdown of cell surface architecture and reduced exposed 1,3 β-glucan in hyphae. Our report shows how Candida uses host and pathogen pathways for macrophage killing. The current model of mechanical piercing of macrophages by C. albicans hyphae should be revised to include activation of pyroptosis by hyphae as an important mechanism mediating macrophage cell death upon C. albicans infection. IMPORTANCE Upon phagocytosis by macrophages, Candida albicans can transition to the hyphal form, which causes macrophage death and enables fungal escape. The current model is that the highly polarized growth of hyphae results in macrophage piercing. This model is challenged by recent

  11. Inhibition of alcoholic fermentation by substrate and ethanol. [Candida pseudotropicalis

    SciTech Connect

    Maulin, H.B.; Galzy, P.

    1980-11-01

    The effect of ethanol and sugars on rates of fermentation was studied. A strain of Candida pseudotropicalis was used. The specific rate of fermentation was determined by using the Warburg manometer. The effect of ethanol was formulated as an exponential function of ethanol concentration, but the empirical constant was different when glucose or lactose was used as a substrate. The effects of both ethanol and substrate were formulated. It was demonstrated that when lactose and glucose were present in the medium with a small amount of alcohol, a synergistic effect on the rate of fermentation appeared. This phenomenon considerably limits the rate of fermentation.

  12. Two new ascomycetous anamorphic yeast species related to Candida friedrichii--Candida jaroonii sp. nov., and Candida songkhlaensis sp. nov.--isolated in Thailand.

    PubMed

    Imanishi, Yumi; Jindamorakot, Sasitorn; Mikata, Kozaburo; Nakagiri, Akira; Limtong, Savitree; Potacharoen, Wanchern; Tanticharoen, Morakot; Nakase, Takashi

    2008-08-01

    In a study of yeast diversity in Thailand, eight strains of hitherto undescribed anamorphic yeasts were isolated: four from insect frass, two from Marasmius sp. fruiting bodies, one from a flower, and one from jackfruit exudates. Phylogenetic analysis of the D1/D2 domain of 26S ribosomal DNA nucleotide sequences indicated that the eight strains represented two new species related to Candida friedrichii. Genetic separation of the two new species was further supported by DNA-DNA hybridization analysis, which resulted in between-species similarity values of less than 48%, and by electrophoretic karyotyping. The two new species are C. jaroonii sp. nov. (type strain, ST-300(T) = NBRC 103209(T) = BCC 11783(T) = CBS 10790(T)) and C. songkhlaensis sp. nov. (type strain, ST-328(T) = NBRC 103214(T) = BCC 11804(T) = CBS 10791(T)).

  13. 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.

  14. Humoral immune responses to Candida albicans complement receptor 3-related protein in the atopic subjects with vulvovaginal candidiasis. Novel sensitive marker for Candida infection.

    PubMed

    Paulovičová, Ema; Bujdáková, Helena; Chupáčová, Jarmila; Paulovičová, Lucia; Kertys, Pavol; Hrubiško, Martin

    2015-03-01

    In vitro evaluation of specific anti-Candida albicans sera antibodies based on synthetically prepared complement receptor 3-related protein (CR3-RP) mimicking the structure of native complement receptor 3 in a cohort of 72 patients with atopy and recurrent Candida vulvovaginitis (RVC) revealed effective humoral response against Candida CR3-RP. The most significant have been IgM and IgA isotype antibodies (33 and 47% positive cases, respectively). The quantitative evaluation of anti-CR3RP isotype antibodies was confronted with results of commercial ELISA anti-C. albicans antibodies diagnostics based on C. albicans cell wall mannan and β-glucan antigens, the most significant correlation being observed with anti-CR3-RP IgM and anti-β-D-glucan IgM (r(2) = 0.624) followed by isotype IgA (r(2) = 0.381). The immunogenicity and immunoreactivity of CR3RP antigen in RVC patients' sera had been evaluated with regard to the results reached by counterimmunoelectrophoresis and heterogeneous enzyme immunoassay. Obviously, synthetically prepared CR3-RP mimicking the Candida cell-wall-derived structure moiety represents a promising immunological tool not only for Candida serodiagnostics, but also prospectively for follow-up of targeted antifungal therapy and as promising Candida vaccine candidate.

  15. 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)).

  16. Candida albicans Inhibits Pseudomonas aeruginosa Virulence through Suppression of Pyochelin and Pyoverdine Biosynthesis

    PubMed Central

    Lopez-Medina, Eduardo; Fan, Di; Coughlin, Laura A.; Ho, Evi X.; Lamont, Iain L.; Reimmann, Cornelia; Hooper, Lora V.; Koh, Andrew Y.

    2015-01-01

    Bacterial-fungal interactions have important physiologic and medical ramifications, but the mechanisms of these interactions are poorly understood. The gut is host to trillions of microorganisms, and bacterial-fungal interactions are likely to be important. Using a neutropenic mouse model of microbial gastrointestinal colonization and dissemination, we show that the fungus Candida albicans inhibits the virulence of the bacterium Pseudomonas aeruginosa by inhibiting P. aeruginosa pyochelin and pyoverdine gene expression, which plays a critical role in iron acquisition and virulence. Accordingly, deletion of both P. aeruginosa pyochelin and pyoverdine genes attenuates P. aeruginosa virulence. Heat-killed C. albicans has no effect on P. aeruginosa, whereas C. albicans secreted proteins directly suppress P. aeruginosa pyoverdine and pyochelin expression and inhibit P. aeruginosa virulence in mice. Interestingly, suppression or deletion of pyochelin and pyoverdine genes has no effect on P. aeruginosa’s ability to colonize the GI tract but does decrease P. aeruginosa’s cytotoxic effect on cultured colonocytes. Finally, oral iron supplementation restores P. aeruginosa virulence in P. aeruginosa and C. albicans colonized mice. Together, our findings provide insight into how a bacterial-fungal interaction can modulate bacterial virulence in the intestine. Previously described bacterial-fungal antagonistic interactions have focused on growth inhibition or colonization inhibition/modulation, yet here we describe a novel observation of fungal-inhibition of bacterial effectors critical for virulence but not important for colonization. These findings validate the use of a mammalian model system to explore the complexities of polymicrobial, polykingdom infections in order to identify new therapeutic targets for preventing microbial disease. PMID:26313907

  17. The Role of Mms22p in DNA Damage Response in Candida albicans

    PubMed Central

    Yan, Lan; Xiong, Juan; Lu, Hui; Lv, Quan-zhen; Ma, Qian-yao; Côte, Pierre; Whiteway, Malcolm; Jiang, Yuan-ying

    2015-01-01

    To ensure correct DNA replication, eukaryotes have signaling pathways that respond to replication-associated DNA damage and trigger repair. In both Saccharomyces cerevisiae and Schizosaccharomyces pombe, a complex of proteins, including the cullin protein Rtt101p and two adapter proteins Mms22p and Mms1p, is important for proper response to replication stress. We have investigated this system in Candida albicans. In this pathogen, Mms22p is important for recovery from DNA replication damage induced by agents including methylmethane sulfonate, camptothecin, and ionizing radiation. Although no clear ortholog of Mms1p has been identified in C. albicans, loss of either Mms22p or Rtt101p generates similar damage sensitivity, consistent with a common function. In S. cerevisiae, the Mrc1p−Csm3p−Tof1p complex stabilizes stalled replication forks and activates a replication checkpoint and interacts with Mms22p. A similar complex in S. pombe, consisting of the Tof1p and Csm3p orthologs Swi1p and Swi3p, along with the fission yeast Mrc1p, genetically also interacts with Mms22p. Intriguingly in C. albicans only Mrc1p and Csm3p appear involved in damage repair, and Mms22p is required for responding to DNA damage agents in MRC1 or CSM3 conditional mutants. In C. albicans, although the loss of RAD57 greatly impairs response in the pathogen to many DNA-damaging agents, lethality due to camptothecin damage requires concomitant loss of Rad57p and Mms22p, suggesting that Mms22p is only essential for homologous recombination induced by camptothecin. These results establish that although C. albicans uses conserved cellular modules to respond to DNA damage and replication blocks, the specific details of these modules differ significantly from the S. cerevisiae model. PMID:26438292

  18. Demineralizing potential of dental biofilm added with Candida albicans and Candida parapsilosis isolated from preschool children with and without caries.

    PubMed

    Caroline de Abreu Brandi, Thayse; Portela, Maristela Barbosa; Lima, Paula Moraes; Castro, Gloria Fernanda Barbosa de Araújo; Maia, Lucianne Cople; Fonseca-Gonçalves, Andréa

    2016-11-01

    This study aimed to investigate the demineralizing potential of dental biofilm added of Candida albicans (CA) and Candida parapsilosis (CP), isolated from preschoolers with and without caries. Bovine enamel blocks (n = 48), with initial hardness = 341.50 ± 21,83 kg/mm(2) were fixed in 24 well plates containing culture media. A pool of children saliva (PHS) was the inoculum for biofilm formation in the presence or absence of isolated CA or CP in accordance with each group (G n = 8): G1 - PHS; G2 - PHS + CA isolated from children with caries; G3 - PHS + CP isolated from children with caries; G4 - PHS + CA isolated from children without caries; G5 - PHS + CP isolated from children without caries; and G6 - blank control. The plates were incubated at 37 °C for 5 days, with daily changes of culture media. The microhardness loss percentage (MHL%) of the blocks was calculated, taking in account the hardness values before and after the experiment. Dental biofilm became more cariogenic, independently of the isolated Candida species. The highest MHL% was observed in G4 (85.90 ± 8.72%) and G5 (86.13 ± 6.74%) compared to the others (p < 0.001): G1 (34.30 ± 14,30%) < G2 (59.40 ± 10.56%) and G3 (65.80 ± 6.36%) < G6 (13.68 ± 4.86%) (p < 0.001). C. albicans and C. parapsilosis isolates induced the demineralization of the dental enamel.

  19. Evaluation of saliva flow rates, Candida colonization and susceptibility of Candida strains after head and neck radiation.

    PubMed

    Karbach, Julia; Walter, Christian; Al-Nawas, Bilal

    2012-08-01

    Hyposalivation is a long-term effect in patients receiving head and neck radiation. Radiotherapy can predispose oral colonization by Candida species of the mucosa. This study aims to evaluate the correlation between hyposalivation, measured by unstimulated saliva flow rates (SFR) and fungal colonization of the oral cavity, and also the resistance of isolated Candida strains to antimicrobial therapy. Fifty-three consecutive patients with radiotherapy were examined for late radiation damage on dental hard tissue and the salivary glands (SFR over a period of 5 min). The SFR were divided into three different values of hyposalivation: grade I (SFR 0.1-0.25 ml/min), grade II (SFR ≤0.1 ml/min), and grade III (SFR = 0.0 ml/min). Candidal colonization was defined using Sabouraud agar and identified using API 20C AUX (biomerieux) in the patients' rinsing water. Susceptibility was tested with Etest (amphotericin B, ketoconacole, voriconacole, and fluconacole). Hyposalivation grade I was detected in 23% (9.1 × 10(1) colony forming units (cfu); range, 200-5,900 cfu), hyposalivation grade II in 26% (4.3 × 10(1) cfu; range, 110-3,300 cfu), and hyposalivation grade III in 51% (2.0 × 10(3) cfu; range, 300-19,475 cfu) of patients. A significant correlation between the SFR and candidal colonization and clinical presentation (European Organization for Research and Treatment of Cancer (EORTC) score) was detected (Mann-Whitney test, p = 0.031). Twenty Candida albicans and 27 non-albicans species were identified. The resistance of C. albicans was higher than that of non-albicans strains against antimicrobial agents. By comparison, amphotericin B showed the greatest and fluconazole the least effect. A higher value of hyposalivation correlates with a higher risk of candidal colonization in patients who have received radiotherapy and also with a higher EORTC score. The spectrum of Candida is wide and susceptibility against antifungal therapy differs. In long-term examinations of

  20. Specific pathways mediating inflammasome activation by Candida parapsilosis

    PubMed Central

    Tóth, Adél; Zajta, Erik; Csonka, Katalin; Vágvölgyi, Csaba; Netea, Mihai G.; Gácser, Attila

    2017-01-01

    Candida albicans and C. parapsilosis are human pathogens causing severe infections. The NLRP3 inflammasome plays a crucial role in host defence against C. albicans, but it has been previously unknown whether C. parapsilosis activates this complex. Here we show that C. parapsilosis induces caspase-1 activation and interleukin-1β (IL-1β) secretion in THP-1, as well as primary, human macrophages. IL-1β secretion was dependent on NLRP3, K+-efflux, TLR4, IRAK, Syk, caspase-1, caspase-8 and NADPH-oxidase. Importantly, while C. albicans induced robust IL-1β release after 4 h, C. parapsilosis was not able to stimulate the production of IL-1β after this short incubation period. We also found that C. parapsilosis was phagocytosed to a lesser extent, and induced significantly lower ROS production and lysosomal cathepsin B release compared to C. albicans, suggesting that the low extent of inflammasome activation by C. parapsilosis may result from a delay in the so-called “signal 2”. In conclusion, this is the first study to examine the molecular pathways responsible for the IL-1β production in response to a non-albicans Candida species, and these results enhance our understanding about the immune response against C. parapsilosis. PMID:28225025

  1. Unusually large telomeric repeats in the yeast Candida albicans.

    PubMed Central

    McEachern, M J; Hicks, J B

    1993-01-01

    We have identified sequences at the telomeres of the yeast Candida albicans and have found that they are composed of tandem copies of a 23-bp sequence. Through the cloning of native telomeric ends and the characterization and cloning of a "healed" end, we demonstrate that these repeated sequences are sufficient to function as a telomere. All copies of the 23-bp repeat that have been sequenced from a number of C. albicans strains are identical. In contrast, adjacent subtelomeric sequences are variable both between strains and within the WO-1 strain. In the WO-1 strain, the lengths of the telomeres are dependent upon growth temperature and are substantially longer at higher temperatures. Telomere growth is accompanied by increases in the number of the 23-bp repeats present on the telomeric fragments. These results suggest that either telomerase-maintained telomeres can be more complex in structure than was previously imagined or that Candida telomeres are maintained via a telomerase-independent mechanism. Images PMID:8417351

  2. Galleria mellonella lysozyme induces apoptotic changes in Candida albicans cells.

    PubMed

    Sowa-Jasiłek, Aneta; Zdybicka-Barabas, Agnieszka; Stączek, Sylwia; Wydrych, Jerzy; Skrzypiec, Krzysztof; Mak, Paweł; Deryło, Kamil; Tchórzewski, Marek; Cytryńska, Małgorzata

    2016-12-01

    The greater wax moth Galleria mellonella has been increasingly used as a model host to determine Candida albicans virulence and efficacy of antifungal treatment. The G. mellonella lysozyme, similarly to its human counterpart, is a member of the c-type family of lysozymes that exhibits antibacterial and antifungal activity. However, in contrast to the relatively well explained bactericidal action, the mechanism of fungistatic and/or fungicidal activity of lysozymes is still not clear. In the present study we provide the direct evidences that the G. mellonella lysozyme binds to the protoplasts as well as to the intact C. albicans cells and decreases the survival rate of both these forms in a time-dependent manner. No enzymatic activity of the lysozyme towards typical chitinase and β-glucanase substrates was detected, indicating that hydrolysis of main fungal cell wall components is not responsible for anti-Candida activity of the lysozyme. On the other hand, pre-treatment of cells with tetraethylammonium, a potassium channel blocker, prevented them from the lysozyme action, suggesting that lysozyme acts by induction of programmed cell death. In fact, the C. albicans cells treated with the lysozyme exhibited typical apoptotic features, i.e. loss of mitochondrial membrane potential, phosphatidylserine exposure in the outer leaflet of the cell membrane, as well as chromatin condensation and DNA fragmentation.

  3. SOME CYTOLOGICAL AND PATHOGENIC PROPERTIES OF SPHEROPLASTS OF CANDIDA ALBICANS

    PubMed Central

    Kobayashi, George S.; Friedman, Lorraine; Kofroth, Judith F.

    1964-01-01

    Kobayashi, George S. (Tulane University, New Orleans, La.), Lorraine Friedman, and Judith F. Kofroth. Some cytological and pathogenic properties of spheroplasts of Candida albicans. J. Bacteriol. 88:795–801. 1964.—Spheroplasts of Candida albicans were prepared by use of an enzymatic mixture from the digestive tract of the snail Helix pomatia. Untreated cells exhibited well-defined cell walls, whereas such structures were absent from spheroplasts. The intravenous inoculation of either spheroplasts or intact cells into rabbits produced a fever which was apparent within 30 min, the “immediate” fever response characteristic of microbial endotoxin. Cell-wall fragments of enzyme-treated cells did not induce a convincing pyrogenic response. When the inoculum was viable, body temperatures did not return to normal but remained elevated until death of the animal 1 or more days later, exhibiting the “delayed” fever of infection. The gross pathological picture in animals succumbing to infection by viable spheroplasts was similar to that obtained with untreated yeast cells. Images PMID:14208520

  4. Ultrastructural analysis of Candida albicans when exposed to silver nanoparticles.

    PubMed

    Vazquez-Muñoz, Roberto; Avalos-Borja, Miguel; Castro-Longoria, Ernestina

    2014-01-01

    Candida albicans is the most common fungal pathogen in humans, and recently some studies have reported the antifungal activity of silver nanoparticles (AgNPs) against some Candida species. However, ultrastructural analyses on the interaction of AgNPs with these microorganisms have not been reported. In this work we evaluated the effect of AgNPs on C. albicans, and the minimum inhibitory concentration (MIC) was found to have a fungicidal effect. The IC50 was also determined, and the use of AgNPs with fluconazole (FLC), a fungistatic drug, reduced cell proliferation. In order to understand how AgNPs interact with living cells, the ultrastructural distribution of AgNPs in this fungus was determined. Transmission electron microscopy (TEM) analysis revealed a high accumulation of AgNPs outside the cells but also smaller nanoparticles (NPs) localized throughout the cytoplasm. Energy dispersive spectroscopy (EDS) analysis confirmed the presence of intracellular silver. From our results it is assumed that AgNPs used in this study do not penetrate the cell, but instead release silver ions that infiltrate into the cell leading to the formation of NPs through reduction by organic compounds present in the cell wall and cytoplasm.

  5. Ultrastructural Analysis of Candida albicans When Exposed to Silver Nanoparticles

    PubMed Central

    Vazquez-Muñoz, Roberto; Avalos-Borja, Miguel; Castro-Longoria, Ernestina

    2014-01-01

    Candida albicans is the most common fungal pathogen in humans, and recently some studies have reported the antifungal activity of silver nanoparticles (AgNPs) against some Candida species. However, ultrastructural analyses on the interaction of AgNPs with these microorganisms have not been reported. In this work we evaluated the effect of AgNPs on C. albicans, and the minimum inhibitory concentration (MIC) was found to have a fungicidal effect. The IC50 was also determined, and the use of AgNPs with fluconazole (FLC), a fungistatic drug, reduced cell proliferation. In order to understand how AgNPs interact with living cells, the ultrastructural distribution of AgNPs in this fungus was determined. Transmission electron microscopy (TEM) analysis revealed a high accumulation of AgNPs outside the cells but also smaller nanoparticles (NPs) localized throughout the cytoplasm. Energy dispersive spectroscopy (EDS) analysis confirmed the presence of intracellular silver. From our results it is assumed that AgNPs used in this study do not penetrate the cell, but instead release silver ions that infiltrate into the cell leading to the formation of NPs through reduction by organic compounds present in the cell wall and cytoplasm. PMID:25290909

  6. Mutants with heteroresistance to amphotericin B and fluconazole in Candida

    PubMed Central

    Claudino, A.L.R.; Peixoto Junior, R.F.; Melhem, M.S.C.; Szeszs, M.W.; Lyon, J.P.; Chavasco, J.K.; Franco, M.C.

    2009-01-01

    Several studies have reported the occurrence of infections caused by Candida yeasts as well as the increasing prevalence of non albicans species. The aim of the present work is focused on the obtaining of heteroresistance to amphotericin B and fluconazole in Candida species using two distinct methodologies: selection and induction. Resistant samples were obtained by selective pressure using a medium with fluconazole for growth, followed by growth in a medium with amphotericin B. The selective pressure was also created beginning with growth in amphotericin B medium followed by growth in fluconazole medium. Concomitantly, samples were submitted to the induction of resistance through cultivation in increasing concentrations of fluconazole, followed by cultivation in increasing concentrations of amphotericin B. Subsequently, the induction began with amphotericin B followed by fluconazole. Three samples resistant to fluconazole and amphotericin B were obtained, two by induction (C. glabrata and C. tropicalis) and one by selection (C. tropicalis). Both C. tropicalis originated from the same wild sample. After successive transfers for drug free medium, only the sample obtained by selection was able to maintain the resistance phenotype. These results suggest that the phenotype of heteroresitance to fluconazole and amphotericin B can be produced by two methodologies: selection and induction. PMID:24031445

  7. Germ tube-specific antigens of Candida albicans cell walls

    SciTech Connect

    Sundstrom, P.R.

    1986-01-01

    Studies were performed to characterize the surface differences between blastospores and germ tubes of the pathogenic, dimorphic yeast, Candida albicans, and to identify components of yeast cells responsible for these differences. Investigation of surfaces differences of the two growth forms was facilitated by the production of rabbit antiserum prepared against Formalin-treated yeast possessing germ tubes. To prepare antiserum specific for germ tubes, this serum was adsorbed with stationary phase blastospores. Whereas the unadsorbed antiserum reacted with both blastospore and germ tube forms by immunofluorescence and Enzyme-Linked Immunosorbent Assay, the adsorbed antiserum did not react with blastospores but detected germ tube-specific antigens in hyphal forms. The differences between blastospores and germ tubes of Candida albicans, were further studied by comparing enzymatic digests of cell walls of both growth forms in radiolabeled organisms. Organisms were labeled either on the surface with /sup 125/I, or metabolically with (/sup 35/S) methionine or (/sup 3/H) mannose. Three-surface-located components (as shown by antibody adsorption and elution experiments) were precipitated from Zymolase digests. All three components were mannoproteins as shown by their ability to bind Concanavalin A, and to be labeled in protein labeling procedures, and two of these (200,000 and 155,000 molecular weight) were germ tube specific, as shown by their ability to be precipitated by germ tube-specific antiserum. Monoclonal antibodies were prepared to C. albicans, using blastospores bearing germ tubes as immunogen.

  8. [Colonization by Candida in a neonatal intensive care unit].

    PubMed

    Caballero-Trejo, Amilcar; Aguirre-Morales, Carlos Eduardo; González-González, Gloria M; Cortés-Palma, Dzoara; Miranda-Novales, María Guadalupe

    2014-01-01

    INTRODUCCIÓN: las infecciones por Candida se han incrementado en las últimas décadas. La colonización previa es el principal factor de riesgo para el desarrollo de fungemia. Es necesario conocer la epidemiología local de un hospital para seleccionar el tratamiento óptimo. El objetivo del estudio que se presenta fue establecer la colonización por especies de Candida en pacientes, personal y dispositivos médicos en una unidad de cuidados intensivos neonatales. MÉTODOS: se llevó a cabo un estudio prospectivo de cohorte. Se obtuvieron muestras de diferentes sitios anatómicos, de dispositivos médicos y de manos del personal de salud, al ingreso de los pacientes y cada siete días hasta el egreso de la unidad. Se realizó identificación de los microorganismos y se determinó su sensibilidad a anfotericina B, fluconazol, itraconazol, voriconazol y caspofungina.

  9. Antimicrobial effects of liquid anesthetic isoflurane on Candida albicans

    PubMed Central

    Barodka, Viachaslau M; Acheampong, Edward; Powell, Garry; Lobach, Ludmila; Logan, David A; Parveen, Zahida; Armstead, Valerie; Mukhtar, Muhammad

    2006-01-01

    Candida albicans is a dimorphic fungus that can grow in yeast morphology or hyphal form depending on the surrounding environment. This ubiquitous fungus is present in skin and mucus membranes as a potential pathogen that under opportunistic conditions causes a series of systemic and superficial infections known as candidiasis, moniliasis or simply candidiasis. There has been a steady increase in the prevalence of candidiasis that is expressed in more virulent forms of infection. Although candidiasis is commonly manifested as mucocutaneous disease, life-threatening systemic invasion by this fungus can occur in every part of the body. The severity of candidal infections is associated with its morphological shift such that the hyphal morphology of the fungus is most invasive. Of importance, aberrant multiplication of Candida yeast is also associated with the pathogenesis of certain mucosal diseases. In this study, we assessed the anti-candidal activity of the volatile anesthetic isoflurane in liquid form in comparison with the anti-fungal agent amphotericin B in an in vitro culture system. Exposure of C. albicans to isoflurane (0.3% volume/volume and above) inhibited multiplication of yeast as well as formation of hyphae. These data suggest development of potential topical application of isoflurane for controlling a series of cutaneous and genital infections associated with this fungus. Elucidiation of the mechanism by which isoflurane effects fungal growth could offer therapeutic potential for certain systemic fungal infections. PMID:17094810

  10. Chloroquine sensitizes biofilms of Candida albicans to antifungal azoles.

    PubMed

    Shinde, Ravikumar Bapurao; Raut, Jayant Shankar; Chauhan, Nitin Mahendra; Karuppayil, Sankunny Mohan

    2013-01-01

    Biofilms formed by Candida albicans, a human pathogen, are known to be resistant to different antifungal agents. Novel strategies to combat the biofilm associated Candida infections like multiple drug therapy are being explored. In this study, potential of chloroquine to be a partner drug in combination with four antifungal agents, namely fluconazole, voriconazole, amphotericin B, and caspofungin, was explored against biofilms of C. albicans. Activity of various concentrations of chloroquine in combination with a particular antifungal drug was analyzed in a checkerboard format. Growth of biofilm in presence of drugs was analyzed by XTT-assay, in terms of relative metabolic activity compared to that of drug free control. Results obtained by XTT-metabolic assay were confirmed by scanning electron microscopy. The interactions between chloroquine and four antifungal drugs were determined by calculating fractional inhibitory concentration indices. Azole resistance in biofilms was reverted significantly (p<0.05) in presence of 250μg/mL of chloroquine, which resulted in inhibition of biofilms at very low concentrations of antifungal drugs. No significant alteration in the sensitivity of biofilms to caspofungin and amphotericin B was evident in combination with chloroquine. This study for the first time indicates that chloroquine potentiates anti-biofilm activity of fluconazole and voriconazole.

  11. Nanocapsules with glycerol monolaurate: Effects on Candida albicans biofilms.

    PubMed

    Lopes, Leonardo Quintana Soares; Santos, Cayane Genro; Vaucher, Rodrigo de Almeida; Raffin, Renata Platcheck; Santos, Roberto Christ Vianna

    2016-08-01

    Candida albicans does not only occur in the free living planktonic form but also grows in surface-attached biofilm communities. Moreover, these biofilms appear to be the most common lifestyle and are involved in the majority of human Candida infections. Nanoparticles can be used as an alternative to conventional antimicrobial agents and can also act as carriers for antibiotics and other drugs. In view of this, the aim of the study was develop, characterize and verify the anti-biofilm potential of GML Nanocapsules against C. albicans. The GML Nanocapsules showed mean diameter of 193.2 nm, polydispersion index of 0.044, zeta potential of -23.3 mV and pH 6.32. The microdilution assay showed MIC of 15.5 μg mL(-1) to GML Nanocapsules and 31.25 μg mL(-1) to GML. The anti-biofilm assay showed the significantly reduction of biomass of C. albicans biofilm treated with GML Nanocapsules while the GML does not exhibit effect. The kinetic assay demonstrated that at 48 h, the GML Nanocapsules reduce 94% of formed biofilm. The positive results suggest the promisor alternative for this public health problem that is biofilm infections.

  12. Influence of Bacterial Presence on Biofilm Formation of Candida albicans

    PubMed Central

    Park, Su Jung; Han, Kyoung-Hee; Park, Joo Young; Choi, Sun Ju

    2014-01-01

    Purpose Candida albicans is an opportunistic pathogen that is commonly found in human microflora. Biofilm formation (BF) is known as a major virulence factor of C. albicans. The aim of this study was to examine the influence of bacterial presence on biofilm formation of C. albicans. Materials and Methods The BF of Candida was investigated when it was co-cultured with C. albicans (C. albicans 53, a yeast with a low BF ability, and C. albicans 163, a yeast with high BF ability) and bacteria. BF was assessed with XTT reduction assay. A scanning electron microscope was used to determine the structure of the biofilm, and real-time reverse transcriptase polymerase chain reaction was used to amplify and quantify hyphae-associated genes. Results Co-culturing with two different types of bacteria increased the BF value. Co-culturing with C. albicans 53 and 163 also increased the BF value compared to the value that was obtained when the C. albicans was cultured individually. However, co-culturing with bacteria decreased the BF value of C. albicans, and the BF of C. albicans 163 was markedly inhibited. The expression of adherence and morphology transition related genes were significantly inhibited by co-culturing with live bacteria. Conclusion Bacteria have a negative effect on the formation of biofilm by C. albicans. This mechanism is the result of the suppression of genes associated with the hyphae transition of C. albicans, and bacteria particles physically affected the biofilm architecture and biofilm formation. PMID:24532517

  13. Candida albicans Ultrastructure: Colonization and Invasion of Oral Epithelium

    PubMed Central

    Howlett, Julie A.; Squier, Christopher A.

    1980-01-01

    The colonization and invasion of various animal oral mucosae by Candida albicans were examined in an organ culture model. Scanning and transmission electron microscopy of the oral epithelium between 12 and 30 h after inoculation with the fungus revealed the morphological relationships between host and parasite. Examination of the fungi in thin sections showed five distinct layers in the cell wall of C. albicans within the epithelium, but changes were evident in the organization and definition of the outer cell wall layers in budding hyphae and in hyphae participating in colonization and invasion of the epithelial cells. Adherence of the fungus to the superficial cells of the oral mucosa appeared to involve intimate contact between the epithelial cell surface and the deeper layers of the fungal cell wall. During invasion a close seal was maintained between the invading hyphae and the surrounding epithelial cell envelope, there being no other evidence of damage to the host cell surface except at the site of entry. Within the epithelial cells there was only occasional loss of cytoplasmic components in the vicinity of the invading hyphae. These findings would suggest that enzymatic lysis associated with the invasive process is localized and that the mechanical support provided by surface adherence and the intimate association between the fungus and the epithelial cell envelope may permit growth of Candida on through the epithelium. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 PMID:6995338

  14. Candida albicans-induced inflammatory response in human keratinocytes.

    PubMed

    Wollina, U; Künkel, W; Bulling, L; Fünfstück, C; Knöll, B; Vennewald, I; Hipler, U-C

    2004-06-01

    Candida albicans strains 3153a, ATCC 48867, CBS 2730, DSM 70014, and Vir 13 were cultivated and sterile C. albicans filtrates were produced. The interaction of soluble Candida factors of these infiltrates with human HaCaT keratinocytes was assayed in vitro. The following parameters were analyzed: cell proliferation, protein synthesis, nuclear matrix protein (NMP) 41 release, cytokine release (IL-1beta, soluble IL-2 receptor, IL-6, and IL-8), and reactive oxygen species (ROS). Cell counts at 1, 12, and 24 h were significantly lower for C. albicans strains CBS 2730 and VIR 13 (P < 0.05). There was no significant change for the remaining strains. Neither the protein synthesis nor the NMP-41 release was significantly affected. IL-6 and IL-8 were stimulated by C. albicans filtrates to different amounts with higher levels in strains of low virulence. There was no effect on the other cytokines. The production of ROS by HaCaT keratinocytes was suppressed. The induction of an inflammatory keratinocyte response by soluble C. albicans factors may play a role among the host-yeast interactions.

  15. Histone Deacetylases and Their Inhibition in Candida Species

    PubMed Central

    Garnaud, Cécile; Champleboux, Morgane; Maubon, Danièle; Cornet, Muriel; Govin, Jérôme

    2016-01-01

    Fungi are generally benign members of the human mucosal flora or live as saprophytes in the environment. However, they can become pathogenic, leading to invasive and life threatening infections in vulnerable patients. These invasive fungal infections are regarded as a major public health problem on a similar scale to tuberculosis or malaria. Current treatment for these infections is based on only four available drug classes. This limited therapeutic arsenal and the emergence of drug-resistant strains are a matter of concern due to the growing number of patients to be treated, and new therapeutic strategies are urgently needed. Adaptation of fungi to drug pressure involves transcriptional regulation, in which chromatin dynamics and histone modifications play a major role. Histone deacetylases (HDACs) remove acetyl groups from histones and actively participate in controlling stress responses. HDAC inhibition has been shown to limit fungal development, virulence, biofilm formation, and dissemination in the infected host, while also improving the efficacy of existing antifungal drugs toward Candida spp. In this article, we review the functional roles of HDACs and the biological effects of HDAC inhibitors on Candida spp., highlighting the correlations between their pathogenic effects in vitro and in vivo. We focus on how HDAC inhibitors could be used to treat invasive candidiasis while also reviewing recent developments in their clinical evaluation. PMID:27547205

  16. [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.

  17. Interaction of Candida albicans with Human Leukocytes and Serum1

    PubMed Central

    Lehrer, Robert I.; Cline, Martin J.

    1969-01-01

    A quantitative assay of candidacidal activity based on differential staining of non-viable Candida albicans by methylene blue was developed and applied to studies of leukocytes from normal individuals and patients with fungal and other infections. Serum factors were necessary for optimal phagocytosis of C. albicans but lacked direct candidacidal activity. Normal human neutrophils (38 studies) killed 29.0 ± 7.4% of ingested C. albicans in 1 hr. Eosinophils and monocytes killed a smaller percentage. Neutrophil candidacidal activity did not require protein or ribonucleic acid synthesis by the leukocyte but was inhibited by anaerobic conditions, potassium cyanide, and colchicine. Leukocytes of a patient with hereditary myeloperoxidase deficiency and of three children with chronic granulomatous disease phagocytized C. albicans normally, yet failed to kill them. Our data suggest that the neutrophil can play an important role in resistance to Candida infection and that the lysosomal enzyme myeloperoxidase and its oxidant substrate hydrogen peroxide are the major participants in neutrophil candidacidal activity. Images PMID:4182532

  18. Scanning Electron Microscopy of Colonies of Six Species of Candida

    PubMed Central

    Joshi, K. R.; Wheeler, E. E.; Gavin, J. B.

    1973-01-01

    Thirty strains of six species of Candida isolated from patients were cultured for 60 h on Sabouraud agar, freeze-dried, and examined with a scanning electron microscope. The colonies were circular (Candida albicans, C. guilliermondii) or oval (C. tropicalis, C. pseudotropicalis, C. krusei, C. parakrusei) in outline, and those of C. pseudotropicalis and C. krusei had an irregular outline due to a peripheral pseudomycelium. The morphology of individual microorganisms was examined at the margins and apex of those species which lacked a surface coat (C. pseudotropicalis, C. krusei, C. parakrusei, C. guilliermondii), and through cracks in the surface coating of those which showed a surface coat (C. albicans, C. tropicalis). All species showed buds, bud scars, and interconnecting intercellular processes, but were generally spherical (C. albicans, C. tropicalis) or ovoid (C. pseudotropicalis, C. krusei, C. parakrusei, C. guilliermondii) in fixed preparations. In unfixed material, individual organisms were almost invariably indented. Fixation with 3% glutaraldehyde and washing before freeze-drying caused partial removal of the surface coating of colonies of C. albicans and C. tropicalis, which persisted only as irregular sheets or as a filamentous meshwork. This filamentous meshwork was also present among the organisms of colonies of C. albicans, C. tropicalis, and C. pseudotropicalis. It is concluded that these filaments represent the precipitation or unmasking of some component of the intercellular matrix of these organisms. Images PMID:4197906

  19. Multigeneration toxicity of imidacloprid and thiacloprid to Folsomia candida.

    PubMed

    van Gestel, Cornelis A M; de Lima E Silva, Claudia; Lam, Thao; Koekkoek, Jacco C; Lamoree, Marja H; Verweij, Rudo A

    2017-01-23

    In a recent study, we showed that the springtail Folsomia candida was quite sensitive the neonicotinoid insecticides imidacloprid and thiacloprid. This study aimed at determining the toxicity of both compounds to F. candida following exposure over three generations, in natural LUFA 2.2 standard soil. In the first generation, imidacloprid was more toxic than thiacloprid, with LC50s of 0.44 and 9.0 mg/kg dry soil, respectively and EC50s of 0.29 and 1.5 mg/kg dry soil, respectively. The higher LC50/EC50 ratio suggests that thiacloprid has more effects on reproduction, while imidacloprid shows lethal toxicity to the springtails. In the multigeneration tests, using soil spiked at the start of the first generation exposures, imidacloprid had a consistent effect on survival and reproduction in all three generations, with LC50s and EC50s of 0.21-0.44 and 0.12-0.29 mg/kg dry soil, respectively, while thiacloprid-exposed animals showed clear recovery in the second and third generations (LC50 and EC50 > 3.33 mg/kg dry soil). The latter finding is in agreement with the persistence of imidacloprid and the fast degradation of thiacloprid in the test soil.

  20. In vitro efficacy of liposomal amphotericin B, micafungin and fluconazole against non-albicans Candida species biofilms.

    PubMed

    Kawai, Akira; Yamagishi, Yuka; Mikamo, Hiroshige

    2015-09-01

    Non-albicans Candida species are being isolated with increasing frequency. In this study, biofilm formation by Candida tropicalis, Candida parapsilosis and Candida glabrata was evaluated and the activities of liposomal amphotericin B (LAB), micafungin (MFG) and fluconazole (FLC) against these biofilms were assessed using a clinically relevant in vitro model system. LAB exhibited strong activities against the three non-albicans Candida species and showed dose-dependent efficacy. MFG displayed a paradoxical growth effect against the C. tropicalis biofilm. FLC was ineffective for non-albicans biofilms. This study shows that Candida biofilms have unique susceptibility to LAB. The dose-dependent effects of LAB indicate that this drug may be a useful treatment for biofilm formation by non-albicans Candida species in cases in which the catheter cannot be removed for clinical reasons.

  1. Association of KPC-producing Klebsiella pneumoniae colonization or infection with Candida isolation and selection of non-albicans species.

    PubMed

    Papadimitriou-Olivgeris, Matthaios; Spiliopoulou, Anastasia; Fligou, Fotini; Manolopoulou, Patroula; Spiliopoulou, Iris; Vrettos, Theofanis; Dodou, Vasiliki; Filos, Kriton S; Anastassiou, Evangelos D; Marangos, Markos; Christofidou, Myrto

    2014-11-01

    Clinical specimens from 565 patients hospitalized in 2 intensive care units (ICUs A and B) during a 28-month period were cultured on appropriate media for isolation of Candida. Forty-nine (9%) patients had at least a Candida spp.-positive sample. Candida albicans was the predominant species isolated from 26 (53%) patients. Seventeen patients (3%) developed candidemia. Multivariate analysis showed that obesity, female gender, hospitalization during summer months, admission at ICU B, parenteral nutrition, administration of metronidazole, transplantation, and KPC-producing Klebsiella pneumoniae (KPC-Kp) infection were independently associated with Candida spp. isolation. Candidemia was associated with cortisone administration, KPC-Kp infection, and presence of colostomy or abdominal catheter. Administration of fluconazole was a protective factor for both Candida spp. isolation and infection, leading to selection of Candida non-albicans species. Among several risk factors, KPC-Kp infection and colonization are identified as statistically significant factors associated with Candida isolation, especially of non-albicans species.

  2. Modulated Entry

    NASA Technical Reports Server (NTRS)

    Grant, Frederick C.

    1960-01-01

    The technique of modulation, or variable coefficients, is discussed and the analytical formulation is reviewed. Representative numerical results of the use of modulation are shown for the lifting and nonlifting cases. These results include the effects of modulation on peak acceleration, entry corridor, and heat absorption. Results are given for entry at satellite speed and escape speed. The indications are that coefficient modulation on a vehicle with good lifting capability offers the possibility of sizable loading reductions or, alternatively, wider corridors; thus, steep entries become practical from the loading standpoint. The amount of steepness depends on the acceptable heating penalty. The price of sizable fractions of the possible gains does not appear to be excessive.

  3. Evidence of Fluconazole-Resistant Candida Species in Tortoises and Sea Turtles.

    PubMed

    Brilhante, Raimunda Sâmia Nogueira; Rodrigues, Pedro Henrique de Aragão; de Alencar, Lucas Pereira; Riello, Giovanna Barbosa; Ribeiro, Joyce Fonteles; de Oliveira, Jonathas Sales; Castelo-Branco, Débora de Souza Collares Maia; Bandeira, Tereza de Jesus Pinheiro Gomes; Monteiro, André Jalles; Rocha, Marcos Fábio Gadelha; Cordeiro, Rossana de Aguiar; Moreira, José Luciano Bezerra; Sidrim, José Júlio Costa

    2015-12-01

    The aim of this study was to evaluate the antifungal susceptibility of Candida spp. recovered from tortoises (Chelonoidis spp.) and sea turtles (Chelonia mydas, Caretta caretta, Lepidochelys olivacea, Eretmochelys imbricata). For this purpose, material from the oral cavity and cloaca of 77 animals (60 tortoises and 17 sea turtles) was collected. The collected specimens were seeded on 2% Sabouraud dextrose agar with chloramphenicol, and the identification was carried out by morphological and biochemical methods. Sixty-six isolates were recovered from tortoises, out of which 27 were C. tropicalis, 27 C. famata, 7 C. albicans, 4 C. guilliermondii and 1 C. intermedia, whereas 12 strains were obtained from sea turtles, which were identified as Candida parapsilosis (n = 4), Candida guilliermondii (n = 4), Candida tropicalis (n = 2), Candida albicans (n = 1) and Candida intermedia (n = 1). The minimum inhibitory concentrations for amphotericin B, itraconazole and fluconazole ranged from 0.03125 to 0.5, 0.03125 to >16 and 0.125 to >64, respectively. Overall, 19 azole-resistant strains (14 C. tropicalis and 5 C. albicans) were found. Thus, this study shows that Testudines carry azole-resistant Candida spp.

  4. Photodynamic inactivation of virulence factors of Candida strains isolated from patients with denture stomatitis.

    PubMed

    Pereira, Cristiane Aparecida; Domingues, Nádia; Silva, Michelle Peneluppi; Costa, Anna Carolina Borges Pereira; Junqueira, Juliana Campos; Jorge, Antonio Olavo Cardoso

    2015-12-01

    Candida species are major microorganisms isolated in denture stomatitis (DS), an inflammatory process of the mucosa underlying removable dental prostheses, and express a variety of virulence factors that can increase their pathogenicity. The potential of Photodynamic inactivation (PDI) in planktonic culture, biofilms and virulence factors of Candida strains was evaluated. A total of 48 clinical Candida isolates from individuals wearing removable maxillary prostheses with DS were included in the study. The effects of erythrosine (ER, 200 μM) and a green LED (λ 532 ± 10 nm, 237 mW/cm(2) and 42.63 J/cm(2)) in a planktonic culture were evaluated. The effect of the addition of ER at a concentration of 400 μM together with a green LED was evaluated in biofilms. The virulence factors of all of the Candida strains were evaluated before and after the PDI process in cells derived from biofilm and planktonic assays. All of the Candida species were susceptible to ER and green LED. However, the biofilm structures were more resistant to PDI than the planktonic cultures. PDI also promoted slight reductions in most of the virulence factors of C. albicans and some of the Candida tropicalis strains. These results suggest that the addition of PDI is effective for reducing yeasts and may also reduce the virulence of certain Candida species and decrease their pathogenicity.

  5. Candida albicans survival, growth and biofilm formation are differently affected by mouthwashes: an in vitro study.

    PubMed

    Paulone, Simona; Malavasi, Giulia; Ardizzoni, Andrea; Orsi, Carlotta Francesca; Peppoloni, Samuele; Neglia, Rachele Giovanna; Blasi, Elisabetta

    2017-01-01

    Candida albicans is the most common cause of oral mycoses. The aim of the present study was to investigate in vitro the susceptibility of C. albicans to mouthwashes, in terms of growth, survival and biofilm formation. Candida albicans, laboratory strain SC5314, and 7 commercial mouthwashes were employed: 3 with 0.2% chlorhexidine digluconate; 1 with 0.06% chlorhexidine digluconate and 250 ppm F- sodium fluoride; 3 with fluorine-containing molecules. None of the mouthwashes contained ethanol in their formulations. The anti-Candida effects of the mouthwashes were assessed by disk diffusion, crystal violet and XTT assays. By using five protocols combining different dilutions and contact times the mouthwashes were tested against: 1) C. albicans growth; 2) biofilm formation; 3) survival of fungal cells in early, developing and mature Candida biofilm. Chlorhexidine digluconate-containing mouthwashes consistently exhibited the highest anti-Candida activity, irrespective of the protocols employed. Fungal growth, biofilm formation and survival of Candida cells within biofilm were impaired, the effects strictly depending on both the dilution employed and the time of contact. These in vitro studies provide evidence that mouthwashes exert anti-Candida activity against both planktonic and biofilm fungal structures, but to a different extent depending on their composition. This suggests special caution in the choice of mouthwashes for oral hygiene, whether aimed at prevention or treatment of oral candidiasis.

  6. Clinical significance of the isolation of Candida species from hospitalized patients.

    PubMed

    Magalhães, Yankee C; Bomfim, Maria Rosa Q; Melônio, Luciane C; Ribeiro, Patrícia C S; Cosme, Lécia M; Rhoden, Cristianne R; Marques, Sirlei G

    2015-03-01

    In this study, we isolated and phenotypically identified 108 yeast strains from various clinical specimens collected from 100 hospitalized patients at three tertiary hospitals in São Luís-Maranhão, Brazil, from July to December 2010. The isolates were analyzed for their susceptibility to four of the most widely used antifungal agents in the surveyed hospitals, amphotericin B, fluconazole, 5-flucytosine and voriconazole. The species identified were Candida albicans (41.4%), Candida tropicalis (30.1%), C. glabrata (7.4%), Candida parapsilosis (5.5%), Candida krusei (4.6%), Cryptococcus neoformans (4.6%), Trichosporon spp . (3.7%), Candida norvegensis (0.9%), Rhodotorula glutinis (0.9%) and Pichia farinosa (0.9%). A higher isolation rate was observed in the following clinical specimens: urine (54 isolates; 50%), respiratory tract samples (21 isolates; 19.4%) and blood (20 isolates; 18.6%). Candida albicans isolates were 100% sensitive to all antifungal agents tested, whereas Candida krusei and Crytococcus neoformans displayed intermediate resistance to 5-flucytosine, with Minimal Inhibitory Concentration (MIC) values of 8 mg/mL and 16 mg/mL, respectively. Both strains were also S-DD to fluconazole with an MIC of 16 mg/mL. C. tropicalis was resistant to 5-flucytosine with an MIC of 32 μg/mL. This study demonstrates the importance of identifying the yeast species involved in community and nosocomial infections.

  7. 7-hydroxycalamenene Effects on Secreted Aspartic Proteases Activity and Biofilm Formation of Candida spp.

    PubMed Central

    Azevedo, Mariana M. B.; Almeida, Catia A.; Chaves, Francisco C. M.; Rodrigues, Igor A.; Bizzo, Humberto R.; Alviano, Celuta S.; Alviano, Daniela S.

    2016-01-01

    Background: The 7-hydroxycalamenenene-rich essential oil (EO) obtained from the leaves of Croton cajucara (red morphotype) have been described as active against bacteria, protozoa, and fungi species. In this work, we aimed to evaluate the effectiveness of 7-hydroxycalamenenene against Candida albicans and nonalbicans species. Materials and Methods: C. cajucara EO was obtained by hydrodistillation and its major compound, 7-hydroxycalamenene, was purified using preparative column chromatography. The anti-candidal activity was investigated by minimum inhibitory concentration (MIC) and secreted aspartic proteases (SAP) and biofilm inhibition assays. Results: 7-hydroxycalamenene (98% purity) displayed anti-candidal activity against all Candida species tested. Higher activity was observed against Candida dubliniensis, Candida parapsilosis and Candida albicans, showing MIC values ranging from 39.06 μg/ml to 78.12 μg/ml. The purified 7-hydroxycalamenene was able to inhibit 58% of C. albicans ATCC 36801 SAP activity at MIC concentration (pH 7.0). However, 7-hydroxycalamenene demonstrated poor inhibitory activity on C. albicans ATCC 10231 biofilm formation even at the highest concentration tested (2500 μg/ml). Conclusion: The bioactive potential of 7-hydroxycalamenene against planktonic Candida spp. further supports its use for the development of antimicrobials with anti-candidal activity. SUMMARY Croton cajucara Benth. essential oil provides high amounts of 7-hydroxycalamenene7-Hydroxycalameneneisolated from C. cajucarais active against Candida spp7-Hydroxycalameneneinhibits C. albicans aspartic protease activity7-Hydroxycalamenene was not active against C. albicans biofilm formation. Figure PMID:27019560

  8. Toxicity and repellency of Tephrosia candida to larval and adult Diaprepes root weevil (Coleoptera: Curculionidae).

    PubMed

    Lapointe, Stephen L; McKenzie, C L; Hunter, Wayne B

    2003-06-01

    Leaves of the tropical legume Tephrosia candida DC deterred feeding by adults of the Diaprepes root weevil, Diaprepes abbreviatus (L.), compared with leaves of Citrus macrophylla Wester, a common citrus rootstock, or T. vogelii Hook. f. When larvae were placed in pots containing plants of the three species for 28 d in a growth chamber, larval survival and weight gain were significantly reduced in pots containing plants of T. candida compared with larvae in pots with C. macrophylla or T. vogelii. Diet incorporation of lyophilized roots of T. candida into an artificial diet increasingly inhibited the growth of larvae and increased larval mortality with increased concentration of roots, whereas roots from C. macrophylla or T. vogelii had no effect compared with the diet-only control. T. candida, but not T. vogelii, contains at least one constituent that acts as an antifeedant toward adult D. abbreviatus and as a toxicant toward larvae. No antifeedant effect of roots of T. candida toward larvae was observed in no-choice pot tests or in a diet incorporation bioassay. In pots, larval feeding damage to roots of T. candida was evident. In the diet incorporation assay, 97% of larvae survived 29 d on a diet of cellulose powder (a nutritionally inert filler) despite losing weight. We conclude that decreased survival and weight gain of larvae-fed fresh or lyophilized roots of T. candida were the result of ingestion of a toxicant and not deterrence from feeding.

  9. Virulence and pathogenicity of Candida albicans is enhanced in biofilms containing oral bacteria.

    PubMed

    Cavalcanti, Yuri Wanderley; Morse, Daniel James; da Silva, Wander José; Del-Bel-Cury, Altair Antoninha; Wei, Xiaoqing; Wilson, Melanie; Milward, Paul; Lewis, Michael; Bradshaw, David; Williams, David Wynne

    2015-01-01

    This study examined the influence of bacteria on the virulence and pathogenicity of candidal biofilms. Mature biofilms (Candida albicans-only, bacteria-only, C. albicans with bacteria) were generated on acrylic and either analysed directly, or used to infect a reconstituted human oral epithelium (RHOE). Analyses included Candida hyphae enumeration and assessment of Candida virulence gene expression. Lactate dehydrogenase (LDH) activity and Candida tissue invasion following biofilm infection of the RHOE were also measured. Candida hyphae were more prevalent (p < 0.05) in acrylic biofilms also containing bacteria, with genes encoding secreted aspartyl-proteinases (SAP4/SAP6) and hyphal-wall protein (HWP1) up-regulated (p < 0.05). Candida adhesin genes (ALS3/EPA1), SAP6 and HWP1 were up-regulated in mixed-species biofilm infections of RHOE. Multi-species infections exhibited higher hyphal proportions (p < 0.05), up-regulation of IL-18, higher LDH activity and tissue invasion. As the presence of bacteria in acrylic biofilms promoted Candida virulence, consideration should be given to the bacterial component when managing denture biofilm associated candidoses.

  10. Ammonium assimilation by Candida albicans and other yeasts: evidence for activity of glutamate synthase.

    PubMed

    Holmes, A R; Collings, A; Farnden, K J; Shepherd, M G

    1989-06-01

    Activities and properties of the ammonium assimilation enzymes NADP+-dependent glutamate dehydrogenase (GDH), glutamate synthase (GOGAT) and glutamine synthetase (GS) were determined in batch and continuous cultures of Candida albicans. NADP+-dependent GDH activity showed allosteric kinetics, with an S0.5 for 2-oxoglutarate of 7.5 mM and an apparent Km for ammonium of 5.0 mM. GOGAT activity was affected by the buffer used for extraction and assay, but in phosphate buffer, kinetics were hyperbolic, yielding Km values for glutamine of 750 microM and for 2-oxoglutarate of 65 microM. The enzymes GOGAT and NADP+-dependent GDH were also assayed in batch cultures of Saccharomyces cerevisiae and three other pathogenic Candida spp.: Candida tropicalis, Candida pseudotropicalis and Candida parapsilosis. Evidence is presented that GS/GOGAT is a major pathway for ammonium assimilation in Candida albicans and that this pathway is also significant in other Candida species.

  11. 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.

  12. Deciphering the toxicity of bisphenol a to Candida rugosa lipase through spectrophotometric methods.

    PubMed

    Zhang, Rui; Zhao, Lining; Liu, Rutao

    2016-10-01

    Bisphenol A is widely used in the manufacture of food packaging and beverage containers and can invade our food and cause contamination. Candida rugose lipase has been a versatile enzyme for biocatalysis and biotransformations to produce useful materials for food, pharmaceutical and flavor. The interactions between bisphenol A and Candida rugosa lipase in vitro were studied by UV-vis, steady-state fluorescence, circular dichroism, synchronous fluorescence, light scattering spectra, molecular docking and enzyme activity assay to better understand the toxicity and toxic mechanisms of bisphenol A. The intrinsic fluorescence of the tryptophan amino acid residue and the secondary structure of the globular protein candida rugose lipase were made use of to thoroughly investigate the structural changes caused by bisphenol A. The results of the fluorescence indicated that bisphenol A interacted with candida rugose lipase and made tryptophan be exposed to a hydrophobic environment. Multi-spectroscopic measurements showed that the addition of bisphenol A increased the intrinsic fluorescence of Candida rugosa lipase, loosened its skeleton structure and changed its secondary structure. Also, the increased activity of Candida rugosa lipase revealed that the position or the structure of the catalytic triad of Candida rugosa lipase may be changed. The molecular docking results showed that bisphenol A bound with the residue Serine 209 which could be another reason for the increased activity of Candida rugosa lipase. Moreover, as can be seen from the results of resonance light scattering and dynamic light scattering, the volume of the Candida rugosa lipase was decreased and the lid may be stripped.

  13. Moonlight-like proteins of the cell wall protect sessile cells of Candida from oxidative stress.

    PubMed

    Serrano-Fujarte, Isela; López-Romero, Everardo; Cuéllar-Cruz, Mayra

    2016-01-01

    Biofilms of Candida species are associated with high morbidity and hospital mortality. Candida forms biofilms by adhering to human host epithelium through cell wall proteins (CWP) and simultaneously neutralizing the reactive oxygen species (ROS) produced during the respiratory burst by phagocytic cells. The purpose of this paper is to identify the CWP of Candida albicans, Candida glabrata, Candida krusei and Candida parapsilosis expressed after exposure to different concentrations of H2O2 using a proteomic approach. CWP obtained from sessile cells, both treated and untreated with the oxidizing agent, were resolved by one and two-dimensional (2D-PAGE) gels and identified by liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis. Some of these proteins were identified and found to correspond to moonlighting CWP such as: (i) glycolytic enzymes, (ii) heat shock, (iii) OSR proteins, (iv) general metabolic enzymes and (v) highly conserved proteins, which are up- or down-regulated in the presence or absence of ROS. We also found that the expression of these CWP is different for each Candida species. Moreover, RT-PCR assays allowed us to demonstrate that transcription of the gene coding for Eno1, one of the moonlight-like CWP identified in response to the oxidant agent, is differentially regulated. To our knowledge this is the first demonstration that, in response to oxidative stress, each species of Candida, differentially regulates the expression of moonlighting CWP, which may protect the organism from the ROS generated during phagocytosis. Presumptively, these proteins allow the pathogen to adhere and form a biofilm, and eventually cause invasive candidiasis in the human host. We propose that, in addition to the antioxidant mechanisms present in Candida, the moonlighting CWP also confer protection to these pathogens from oxidative stress.

  14. Glycerol Monolaurate Inhibits Candida and Gardnerella vaginalis In Vitro and In Vivo but Not Lactobacillus▿

    PubMed Central

    Strandberg, Kristi L.; Peterson, Marnie L.; Lin, Ying-Chi; Pack, Melinda C.; Chase, David J.; Schlievert, Patrick M.

    2010-01-01

    We investigated the effects of glycerol monolaurate (GML) on Lactobacillus, Candida, and Gardnerella vaginalis human vaginal microflora. Our previous work demonstrated that 6 months of GML treatment vaginally does not alter lactobacillus counts in monkeys. Candida and G. vaginalis are commonly associated with vaginal infections in women, many becoming chronic or recurrent. In vitro growth inhibition studies determined the effects of GML (0 to 500 μg/ml) against multiple Candida species and G. vaginalis. A randomized, double-blind study investigated the effects of GML on vaginal microflora Lactobacillus, Candida, and G. vaginalis in colonized or infected women (n = 36). Women self-administered intravaginal gels containing 0% (n = 14), 0.5% (n = 13), or 5% (n = 9) GML every 12 h for 2 days. Vaginal swabs were collected before and immediately after the first gel administration and 12 h after the final gel administration. Swabs were tested for Lactobacillus, Candida, G. vaginalis, and GML. In vitro GML concentrations of 500 μg/ml were candicidal for all species tested, while a concentration of 10 μg/ml was bactericidal for G. vaginalis. Control and GML gels applied vaginally in women did not alter vaginal pH or Lactobacillus counts. Control gels reduced G. vaginalis counts but not Candida counts, whereas GML gels reduced both Candida and G. vaginalis. No adverse events were reported by participating women. GML is antimicrobial for Candida and G. vaginalis in vitro. Vaginal GML gels in women do not affect Lactobacillus negatively but significantly reduce Candida and G. vaginalis. PMID:20008774

  15. Glycerol monolaurate inhibits Candida and Gardnerella vaginalis in vitro and in vivo but not Lactobacillus.

    PubMed

    Strandberg, Kristi L; Peterson, Marnie L; Lin, Ying-Chi; Pack, Melinda C; Chase, David J; Schlievert, Patrick M

    2010-02-01

    We investigated the effects of glycerol monolaurate (GML) on Lactobacillus, Candida, and Gardnerella vaginalis human vaginal microflora. Our previous work demonstrated that 6 months of GML treatment vaginally does not alter lactobacillus counts in monkeys. Candida and G. vaginalis are commonly associated with vaginal infections in women, many becoming chronic or recurrent. In vitro growth inhibition studies determined the effects of GML (0 to 500 microg/ml) against multiple Candida species and G. vaginalis. A randomized, double-blind study investigated the effects of GML on vaginal microflora Lactobacillus, Candida, and G. vaginalis in colonized or infected women (n=36). Women self-administered intravaginal gels containing 0% (n=14), 0.5% (n=13), or 5% (n=9) GML every 12 h for 2 days. Vaginal swabs were collected before and immediately after the first gel administration and 12 h after the final gel administration. Swabs were tested for Lactobacillus, Candida, G. vaginalis, and GML. In vitro GML concentrations of 500 microg/ml were candicidal for all species tested, while a concentration of 10 microg/ml was bactericidal for G. vaginalis. Control and GML gels applied vaginally in women did not alter vaginal pH or Lactobacillus counts. Control gels reduced G. vaginalis counts but not Candida counts, whereas GML gels reduced both Candida and G. vaginalis. No adverse events were reported by participating women. GML is antimicrobial for Candida and G. vaginalis in vitro. Vaginal GML gels in women do not affect Lactobacillus negatively but significantly reduce Candida and G. vaginalis.

  16. Differentiation of Candida albicans and Candida dubliniensis by Fluorescent In Situ Hybridization with Peptide Nucleic Acid Probes

    PubMed Central

    Oliveira, Kenneth; Haase, Gerhard; Kurtzman, Cletus; Hyldig-Nielsen, Jens Jo/rgen; Stender, Henrik

    2001-01-01

    The recent discovery of Candida dubliniensis as a separate species that traditionally has been identified as Candida albicans has led to the development of a variety of biochemical and molecular methods for the differentiation of these two pathogenic yeasts. rRNA sequences are well-established phylogenetic markers, and probes targeting species-specific rRNA sequences have been used in diagnostic assays for the detection and identification of microorganisms. Peptide nucleic acid (PNA) is a DNA mimic with improved hybridization characteristics, and the neutral backbone of PNA probes offers significant advantages in whole-cell in situ hybridization assays. In this study, we developed PNA probes targeting the rRNAs of C. albicans and C. dubliniensis and applied them to a fluorescence in situ hybridization method (PNA FISH) for differentiation between C. albicans and C. dubliniensis. Liquid cultures were smeared onto microscope slides, heat fixed, and then hybridized for 30 min. Unhybridized PNA probe was removed by washing, and smears were examined by fluorescence microscopy. Evaluation of the PNA FISH method using smears of 79 C. dubliniensis and 70 C. albicans strains showed 100% sensitivity and 100% specificity for both PNA probes. We concluded that PNA FISH is a powerful tool for the differentiation of C. albicans and C. dubliniensis. PMID:11682542

  17. Extensive chromosome rearrangements distinguish the karyotype of the hypovirulent species Candida dubliniensis from the virulent Candida albicans

    PubMed Central

    Magee, B B; Sanchez, Melissa D; Saunders, David; Harris, David; Berriman, M.; Magee, PT

    2008-01-01

    Candida dubliniensis and Candida albicans, the most common human fungal pathogen, have most of the same genes and high sequence similarity, but C. dubliniensis is less virulent. C. albicans causes both mucosal and hematogenously disseminated disease, C. dubliniensis mostly mucosal infections. Pulse-field electrophoresis, genomic restriction enzyme digests, Southern blotting, and the emerging sequence from the Wellcome Trust Sanger Institute were used to determine the karyotype of C. dubliniensis type strain CD36. Three chromosomes have two intact homologues. A translocation in the rDNA repeat on chromosome R exchanges telomere-proximal regions of R and chromosome 5. Translocations involving the remaining chromosomes occur at the Major Repeat Sequence. CD36 lacks an MRS on chromosome R but has one on 3. Of six other C. dubliniensis strains, no two had the same electrophoretic karyotype. Despite extensive chromosome rearrangements, karyotypic differences between C. dubliniensis and C. albicans are unlikely to affect gene expression. Karyotypic instability may account for the diminished pathogenicity of C. dubliniensis. PMID:17719250

  18. Clusters of patients with candidaemia due to genotypes of Candida albicans and Candida parapsilosis: differences in frequency between hospitals.

    PubMed

    Marcos-Zambrano, L J; Escribano, P; Sanguinetti, M; Gómez G de la Pedrosa, E; De Carolis, E; Vella, A; Cantón, R; Bouza, E; Guinea, J

    2015-07-01

    The presence of clusters (identical genotypes infecting different patients) suggests patient-to-patient transmission or a common source for strains. We report the results of a genotyping study based on microsatellite markers of Candida albicans (n = 179) and Candida parapsilosis (n = 76) causing candidaemia, to assess and compare the percentage of patients grouped in clusters during the study period (January 2010 to December 2012). The study was performed in two large tertiary hospitals in Madrid, Spain. We detected 145 C. albicans genotypes (21 in clusters) and 63 C. parapsilosis genotypes (seven in clusters). Clusters involved two to seven patients each. Most of the clusters in the two centres involved two patients for both species, but the number of patients included in each cluster differed between hospitals. Considering both species, the percentage of patients per cluster ranged from 19% to 38% (p < 0.05) in Hospital A and B respectively. Up to 2.9% of genotypes were present in both hospitals. Clusters of C. albicans and C. parapsilosis genotypes causing candidaemia differed between hospitals, suggesting differences in strain transmission. Occasionally, the same genotypes were found in patients admitted to different hospitals located in the same city.

  19. Comparison of Switching and Biofilm Formation between MTL-Homozygous Strains of Candida albicans and Candida dubliniensis.

    PubMed

    Pujol, Claude; Daniels, Karla J; Soll, David R

    2015-12-01

    Candida albicans and Candida dubliniensis are highly related species that share the same main developmental programs. In C. albicans, it has been demonstrated that the biofilms formed by strains heterozygous and homozygous at the mating type locus (MTL) differ functionally, but studies rarely identify the MTL configuration. This becomes a particular problem in studies of C. dubliniensis, given that one-third of natural strains are MTL homozygous. For that reason, we have analyzed MTL-homozygous strains of C. dubliniensis for their capacity to switch from white to opaque, the stability of the opaque phenotype, CO2 induction of switching, pheromone induction of adhesion, the effects of minority opaque cells on biofilm thickness and dry weight, and biofilm architecture in comparison with C. albicans. Our results reveal that C. dubliniensis strains switch to opaque at lower average frequencies, exhibit a far lower level of opaque phase stability, are not stimulated to switch by high CO2, exhibit more variability in biofilm architecture, and most notably, form mature biofilms composed predominately of pseudohyphae rather than true hyphae. Therefore, while several traits of MTL-homozygous strains of C. dubliniensis appear to be degenerating or have been lost, others, most notably several related to biofilm formation, have been conserved. Within this context, the possibility is considered that C. dubliniensis is transitioning from a hypha-dominated to a pseudohypha-dominated biofilm and that aspects of C. dubliniensis colonization may provide insights into the selective pressures that are involved.

  20. Comparison of virulence factors of oral Candida dubliniensis and Candida albicans isolates in healthy people and patients with chronic candidosis.

    PubMed

    Hannula, J; Saarela, M; Dogan, B; Paatsama, J; Koukila-Kähkölä, P; Pirinen, S; Alakomi, H L; Perheentupa, J; Asikainen, S

    2000-08-01

    We determined differences in the expression of certain virulence factors between oral Candida dubliniensis and Candida albicans species. In addition, clonal differences were sought among C. albicans isolates recovered from patients with and without compromised immune system. The material comprised 93 clinical yeast isolates originated in 40 subjects (1-5 isolates per subject). All 26 C. dubliniensis isolates and 46 C. albicans isolates originated from healthy routine dental clinic patients. Additionally, 21 C. albicans isolates were collected from patients with autoimmune polyendocrinopathy-candidosis-ectodermal dystrophy (APECED), who have chronic candidosis as one manifestation of their immunocompromising disease. Polymerase chain reaction amplification using the random sequence primer OPE-03 enabled grouping of the C. dubliniensis isolates in 2 genotypes (I and II) and C. albicans isolates in 15 genotypes (I-XV). No significant difference was found in the distribution of genotypes between the patients with APECED and the healthy subjects. C. dubliniensis isolates exhibited high-frequency phenotypic switching significantly more frequently than did C. albicans isolates, and vice versa regarding phospholipase and proteinase production. Proteinase production was significantly more frequent among C. albicans genotype V than genotype IX isolates. No significant difference was found in expression of virulence factors of C. albicans isolates between the patients with APECED and the healthy subjects.

  1. Firefighting Module

    NASA Technical Reports Server (NTRS)

    1978-01-01

    NASA and the U.S. Coast Guard are working jointly to develop a helicopter transportable firefighting module that can shave precious minutes in combating shipboard or harbor fires. The program was undertaken in 1975, after a series of disastrous fires on oil tankers indicated a need for a lightweight, self-contained system that could be moved quickly to the scene of a fire. A prototype module was delivered to the Coast Guard last year and service testing is under way. The compact module weighs little more than a ton but it contains everything needed to fight a fire. The key component is a high output pump, which delivers up to 2,000 gallons of sea water a minute; the pump can be brought up to maximum output in only one minute after turning on the power source, a small Allison gas turbine engine. The module also contains hose, a foam nozzle and a spray nozzle, three sets of protective clothing for firefighters, and fuel for three hours operation. Designed to be assembled without special tools, the module can be set up for operation in less than 20 minutes.

  2. Antimicrobial Efficacy of Probiotic and Herbal Oral Rinses against Candida albicans in Children: A Randomized Clinical Trial

    PubMed Central

    Tandon, Shobha; Rathore, Monika; Banerjee, Molay

    2016-01-01

    ABSTRACT Background: A growing number of dentists are embracing the philosophy that natural agents are better for children’s oral health. Knowledge of probiotics on host immune system has entered a new phase of research, and progression in this field is likely to offer novel means by modulating host immunity for prevention and treatment of a wide variety of oral diseases. Aim: To compare the antimicrobial efficacy of probiotics in reducing salivary Candida albicans counts with commonly used antimicrobial agents like 0.2% chlorhexidine and herbal rinse. Materials and methods: A randomized clinical trial was conducted on 60 subjects aged between 6 and 14 years, for a period of 9 months. The subjects were randomly divided into three groups comprising 20 subjects in each group. Three oral agents were administered twice daily for a maximum period of 1 week. Candida albicans counts were recorded before and after intervention and the results were submitted for statistical analysis using Statistical Package for the Social Sciences (SPSS) version 15.0 software. Results: The change in mean log10 colony-forming unit (CFU)/ ml of C. albicans in groups A to C was 0.43 ± 0.72, 0.68 ± 1.05 and 0.22 ± 0.66 CFU/ml respectively. Conclusion: Data obtained from the study demonstrated that probiotic rinse was equally effective as 0.2% chlorhexidine digluconate rinse in reducing C. albicans counts after 1 week of intervention. Herbal oral rinse was least effective. Probiotic oral rinses have opened new horizons in improvement of oral health by maintaining healthy ecosystem. However, a longitudinal study with larger sample size needs to be undertaken to evaluate the therapeutic effects of probiotics and herbal agents. How to cite this article: Mishra R, Tandon S, Rathore M, Banerjee M. Antimicrobial Efficacy of Probiotic and Herbal Oral Rinses against Candida albicans in Children: A Randomized Clinical Trial. Int J Clin Pediatr Dent 2016;9(1):25-30. PMID:27274151

  3. 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.

  4. 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.

  5. Firefighting Module

    NASA Technical Reports Server (NTRS)

    1980-01-01

    Aviation Power Supply's mobile firefighting module called Firefly II is mounted on a trailer pulled by a pickup truck. Trailer unit has two three- inch water cannons, and the pickup carries a six inch cannon. Completely self contained, module pumps 3,000 gallons of water a minute from hydrants or open bodies of water. Stream can go as far as 400 feet or can be employed in a high-loft mode to reach the tops of tall refinery towers. Compact Firefly II weighs only 2,500 pounds when fully fueled. Key component is a specially designed two stage pump. Power for the pump is generated by a gas turbine engine. Module also includes an electronic/pump controller, multiple hose connections, up to 1,500 feet of hose and fuel for four hours operation. Firefly trailer can be backed onto specially-built large fireboat.

  6. Firefighting Module

    NASA Technical Reports Server (NTRS)

    1981-01-01

    Aviation Power Supply's mobile firefighting module called Firefly II is mounted on a trailer pulled by a pickup truck. Trailer unit has two three- inch water cannons, and the pickup carries a six inch cannon. Completely self contained, module pumps 3,000 gallons of water a minute from hydrants or open bodies of water. Stream can go as far as 400 feet or can be employed in a high-loft mode to reach the tops of tall refinery towers. Compact Firefly II weighs only 2,500 pounds when fully fueled. Key component is a specially designed two stage pump. Power for the pump is generated by a gas turbine engine. Module also includes an electronic/pump controller, multiple hose connections, up to 1,500 feet of hose and fuel for four hours operation. Firefly trailer can be backed onto specially-built large fireboat.

  7. Short term Candida albicans colonization reduces Pseudomonas aeruginosa-related lung injury and bacterial burden in a murine model

    PubMed Central

    2011-01-01

    Introduction Pseudomonas aeruginosa is a frequent cause of ventilator-acquired pneumonia (VAP). Candida tracheobronchial colonization is associated with higher rates of VAP related to P. aeruginosa. This study was designed to investigate whether prior short term Candida albicans airway colonization modulates the pathogenicity of P. aeruginosa in a murine model of pneumonia and to evaluate the effect of fungicidal drug caspofungin. Methods BALB/c mice received a single or a combined intratracheal administration of C. albicans (1 × 105 CFU/mouse) and P. aeruginosa (1 × 107 CFU/mouse) at time 0 (T0) upon C. albicans colonization, and Day 2. To evaluate the effect of antifungal therapy, mice received caspofungin intraperitoneally daily, either from T0 or from Day 1 post-colonization. After sacrifice at Day 4, lungs were analyzed for histological scoring, measurement of endothelial injury, and quantification of live P. aeruginosa and C. albicans. Blood samples were cultured for dissemination. Results A significant decrease in lung endothelial permeability, the amount of P. aeruginosa, and bronchiole inflammation was observed in case of prior C. albicans colonization. Mortality rate and bacterial dissemination were unchanged by prior C. albicans colonization. Caspofungin treatment from T0 (not from Day 1) increased their levels of endothelial permeability and lung P. aeruginosa load similarly to mice receiving P. aeruginosa alone. Conclusions P. aeruginosa-induced lung injury is reduced when preceded by short term C. albicans airway colonization. Antifungal drug caspofungin reverses that effect when used from T0 and not from Day 1. PMID:21689424

  8. Crystal structure of the Candida albicans Kar3 kinesin motor domain fused to maltose-binding protein

    SciTech Connect

    Delorme, Caroline; Joshi, Monika; Allingham, John S.

    2012-11-30

    Highlights: Black-Right-Pointing-Pointer The Candida albicans Kar3 motor domain structure was solved as a maltose-binding protein fusion. Black-Right-Pointing-Pointer The electrostatic surface and part of the ATPase pocket of the motor domain differs markedly from other kinesins. Black-Right-Pointing-Pointer The MBP-Kar3 interface highlights a new site for intramolecular or intermolecular interactions. -- Abstract: In the human fungal pathogen Candida albicans, the Kinesin-14 motor protein Kar3 (CaKar3) is critical for normal mitotic division, nuclear fusion during mating, and morphogenic transition from the commensal yeast form to the virulent hyphal form. As a first step towards detailed characterization of this motor of potential medical significance, we have crystallized and determined the X-ray structure of the motor domain of CaKar3 as a maltose-binding protein (MBP) fusion. The structure shows strong conservation of overall motor domain topology to other Kar3 kinesins, but with some prominent differences in one of the motifs that compose the nucleotide-binding pocket and the surface charge distribution. The MBP and Kar3 modules are arranged such that MBP interacts with the Kar3 motor domain core at the same site where the neck linker of conventional kinesins docks during the 'ATP state' of the mechanochemical cycle. This site differs from the Kar3 neck-core interface in the recent structure of the ScKar3Vik1 heterodimer. The position of MBP is also completely distinct from the Vik1 subunit in this complex. This may suggest that the site of MBP interaction on the CaKar3 motor domain provides an interface for the neck, or perhaps a partner subunit, at an intermediate state of its motile cycle that has not yet been observed for Kinesin-14 motors.

  9. Molecular methods for strain typing of Candida albicans: a review.

    PubMed

    Saghrouni, F; Ben Abdeljelil, J; Boukadida, J; Ben Said, M

    2013-06-01

    Candida albicans is one of the most medically important fungi because of its high frequency as a commensal and pathogenic microorganism causing superficial as well as invasive infections. Strain typing and delineation of the species are essential for understanding its biology, epidemiology and population structure. A wide range of molecular techniques have been used for this purpose including non-DNA-based methods (multi-locus enzyme electrophoresis), conventional DNA-based methods (electrophoretic karyotyping, random amplified polymorphic DNA, amplified fragment length polymorphism, restriction enzyme analysis with and without hybridization, rep-PCR) and DNA-based methods called exact typing methods because they generate unambiguous and highly reproducible typing data (including microsatellite length polymorphism and multi-locus sequence typing). In this review, the main molecular methods used for C. albicans strain typing are summarized, and their advantages and limitations are discussed with regard to their discriminatory power, reproducibility, cost and ease of performance.

  10. Gastrointestinal granuloma due to Candida albicans in an immunocompetent cat

    PubMed Central

    Duchaussoy, Anne-Claire; Rose, Annie; Talbot, Jessica J.; Barrs, Vanessa R.

    2015-01-01

    A 3.5 year-old cat was admitted to the University of Melbourne Veterinary Teaching Hospital for chronic vomiting. Abdominal ultrasonography revealed a focal, circumferential thickening of the wall of the duodenum extending from the pylorus aborally for 3 cm, and an enlarged gastric lymph node. Cytology of fine-needle aspirates of the intestinal mass and lymph node revealed an eosinophilic inflammatory infiltrate and numerous extracellular septate acute angle branching fungal-type hyphae. Occasional hyphae had globose terminal ends, as well as round to oval blastospores and germ tubes. Candida albicans was cultured from a surgical biopsy of the duodenal mass. No underlying host immunodeficiencies were identified. Passage of an abrasive intestinal foreign body was suspected to have caused intestinal mucosal damage resulting in focal intestinal candidiasis. The cat was treated with a short course of oral itraconazole and all clinical signs resolved. PMID:26862475

  11. Adaptation of Candida albicans to commensalism in the gut.

    PubMed

    Prieto, Daniel; Correia, Inês; Pla, Jesús; Román, Elvira

    2016-01-01

    Candida albicans is a common resident of the oral cavity, GI tract and vagina in healthy humans where it establishes a commensal relationship with the host. Colonization of the gut, which is an important niche for the microbe, may lead to systemic dissemination and disease upon alteration of host defences. Understanding the mechanisms responsible for the adaptation of C. albicans to the gut is therefore important for the design of new ways of combating fungal diseases. In this review we discuss the available models to study commensalism of this yeast, the main mechanisms controlling the establishment of the fungus, such as microbiota, mucus layer and antimicrobial peptides, and the gene regulatory circuits that ensure its survival in this niche.

  12. Candida lusitaniae arthritis in an intravenous drug user.

    PubMed

    Jeragh, A; Ahmad, S; Naseem, J; Khan, Z U

    2007-09-01

    A case of arthritis of the right knee caused by Candida lusitaniae in a 29-year-old intravenous drug abuser is described. The diagnosis was based on the isolation of C. lusitaniae from synovial fluid and was supported by the presence of C. lusitaniae-specific DNA and high levels of (1-3)-beta-d-glucan (122 pg ml-1) in the same specimen. While the isolate was susceptible to amphotericin B and fluconazole in vitro, treatment with amphotericin B was not very effective. The patient achieved complete cure with fluconazole therapy only after undergoing synovectomy. To the best of our knowledge, this is the first report of arthritis caused by C. lusitaniae in an intravenous drug user.

  13. Sensitization of Candida albicans to terbinafine by berberine and berberrubine

    PubMed Central

    LAM, PIKLING; KOK, STANTON HON LUNG; LEE, KENNETH KA HO; LAM, KIM HUNG; HAU, DESMOND KWOK PO; WONG, WAI YEUNG; BIAN, ZHAOXIANG; GAMBARI, ROBERTO; CHUI, CHUNG HIN

    2016-01-01

    Candida albicans (C. albicans) is an opportunistic fungal pathogen, particularly observed in immunocompromised patients. C. albicans accounts for 50–70% of cases of invasive candidiasis in the majority of clinical settings. Terbinafine, an allylamine antifungal drug, has been used to treat fungal infections previously. It has fungistatic activity against C. albicans. Traditional Chinese medicines can be used as complementary medicines to conventional drugs to treat a variety of ailments and diseases. Berberine is a quaternary alkaloid isolated from the traditional Chinese herb, Coptidis Rhizoma, while berberrubine is isolated from the medicinal plant Berberis vulgaris, but is also readily derived from berberine by pyrolysis. The present study demonstrates the possible complementary use of berberine and berberrubine with terbinafine against C. albicans. The experimental findings assume that the potential application of these alkaloids together with reduced dosage of the standard drug would enhance the resulting antifungal potency. PMID:27073630

  14. An immunological link between Candida albicans colonization and Crohn's disease.

    PubMed

    Gerard, Romain; Sendid, Boualem; Colombel, Jean-Frederic; Poulain, Daniel; Jouault, Thierry

    2015-06-01

    The etiology of Crohn's disease (CD), an autoimmune, inflammatory bowel disease (IBD) which affects approximately one million people in Europe, is still unclear. Nevertheless, it is widely accepted that CD could result from an inappropriate inflammatory response to intestinal microorganisms in a genetically susceptible host. Most studies to date have concerned the involvement of bacteria in disease progression. In addition to bacteria, there appears to be a possible link between the commensal yeast Candida albicans and disease development. In this review, in an attempt to link the gut colonization process and the development of CD, we describe the different pathways that are involved in the progression of CD and in the host response to C. albicans, making the yeast a possible initiator of the inflammatory process observed in this IBD.

  15. Estrogenic activity of chemical constituents from Tephrosia candida.