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Sample records for candida albicans isolated

  1. 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.

  2. Comparative antifungal susceptibility analysis of Candida albicans versus non-albicans Candida corneal isolates.

    PubMed

    Spierer, Oriel; Dugar, Jyoti; Miller, Darlene; OʼBrien, Terrence P

    2015-05-01

    To compare the in vitro activity of topical amphotericin B (AMB), natamycin, voriconazole, and fluconazole against human corneal isolates of Candida sp. for guidance in the treatment of Candida keratitis. Sixty-eight Candida isolates (37 albicans and 31 non-albicans isolates) recovered from corneal scrapings submitted to rule out microbial keratitis, during the years 2005 to 2011, at the Bascom Palmer Eye Institute, were examined in this study. Corneal isolates were cultured on fungal agars for 48 hours. Each yeast isolate was dispensed into 4 microtiter wells, each containing 100 mL of commercial (natamycin 5%) or compounded (AMB 0.15%, voriconazole 1%, and fluconazole 0.2%) antifungal medications. A comparison of growth patterns was conducted. One hundred percent of the samples showed growth inhibition after treatment exposure with AMB or natamycin. The isolates treated with voriconazole demonstrated an 85% inhibition rate overall, with the Candida albicans samples showing a 77% inhibition rate and the non-albicans sp. a 93% inhibition rate. In the fluconazole group, there was only a 19.6% inhibition rate noted, with a 7.7% inhibition rate observed in the C. albicans group versus a 30% inhibition rate in the non-albicans group. AMB 0.2% and natamycin 5% have equal effectiveness and full inhibition against Candida keratitis isolates. Fluconazole 0.2% is not the drug of choice in both C. albicans and non-albicans keratitis. Voriconazole 1% may need a stronger concentration for higher effectiveness, but potentially may be helpful as a second agent in the treatment of Candida keratitis.

  3. Proteomic Analysis of Azole Resistance in Candida albicans Clinical Isolates

    PubMed Central

    Hooshdaran, Massoumeh Z.; Barker, Katherine S.; Hilliard, George M.; Kusch, Harald; Morschhäuser, Joachim; Rogers, P. David

    2004-01-01

    Changes in protein expression within a matched set of Candida albicans isolates representing the acquisition of azole resistance were examined by two-dimensional polyacrylamide gel electrophoresis and peptide mass fingerprinting. Proteins differentially expressed in association with azole resistance included Grp2p, Ifd1p, Ifd4p, Ifd5p, and Erg10p, a protein involved in the ergosterol biosynthesis pathway. PMID:15215138

  4. Differences in virulence of clinical isolates of Candida tropicalis and Candida albicans in mice.

    PubMed Central

    Wingard, J R; Dick, J D; Merz, W G; Sandford, G R; Saral, R; Burns, W H

    1982-01-01

    Prior reports from this institution indicated that Candida tropicalis was more pathogenic than C. albicans in oncology patients. Pairs of clinical isolates of C. tropicalis and C. albicans recovered from similar patients at other institutions were examined to determine their relative virulence. After intravenous inoculation in normal mice, three pairs of isolates had no significant differences in the 50% lethal dose, and one C. tropicalis isolate was less virulent than its companion C. albicans isolate. In contrast, in mice treated with antibiotics and cytarabine, an antineoplastic drug which damages the gastrointestinal mucosa and produces granulocytopenia, oral inoculation of yeast cells produced striking differences in the 50% infective dose: each C. tropicalis isolate was more virulent than the companion C. albicans isolate from the same institution. The increased virulence of the C. tropicalis isolates compared with the C. albicans isolates when given orally to compromised mice parallels clinical observations in compromised patients. PMID:6749689

  5. Variation of electrophoretic karyotypes among clinical isolates of Candida albicans.

    PubMed Central

    Merz, W G; Connelly, C; Hieter, P

    1988-01-01

    Orthogonal-field-alternation gel electrophoresis was used to compare clinical isolates of Candida albicans by resolving chromosome-sized DNA molecules into an electrophoretic karyotype. Seven to nine bands were observed among isolates recovered from 17 patients. In addition, 14 distinct electrophoretic patterns were noted among the isolates from these patients. In a given individual, isolates were likely to have identical electrophoretic patterns. Therefore, the electrophoretic karyotype patterns demonstrated by orthogonal-field-alternation gel electrophoresis can be used to designate a strain for epidemiologic studies. Images PMID:3290238

  6. 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.

  7. Isolation and characterization of yeast monomorphic mutants of Candida albicans.

    PubMed Central

    Elorza, M V; Sentandreu, R; Ruiz-Herrera, J

    1994-01-01

    A method was devised for the isolation of yeast monomorphic (LEV) mutants of Candida albicans. By this procedure, about 20 stable yeast-like mutants were isolated after mutagenesis with ethyl methane sulfonate. The growth rate of the mutants in different carbon sources, both fermentable and not, was indistinguishable from that of the parental strain, but they were unable to grow as mycelial forms after application of any of the common effective inducers, i.e., heat shock, pH alterations, proline addition, or use of GlcNAc as the carbon source. Studies performed with one selected strain demonstrated that it had severe alterations in the chemical composition of the cell wall, mainly in the levels of chitin and glucans, and in specific mannoproteins, some of them recognizable by specific polyclonal and monoclonal antibodies. It is suggested that these structural alterations hinder the construction of a normal hyphal wall. Images PMID:8157600

  8. Antifungal activity of extracts and isolated compounds from Buchenavia tomentosa on Candida albicans and non-albicans.

    PubMed

    Teodoro, Guilherme R; Brighenti, Fernanda L; Delbem, Alberto C Botazzo; Delbem, Ádina Cléia B; Khouri, Sonia; Gontijo, Aline Vidal L; Pascoal, Aislan Crf; Salvador, Marcos J; Koga-Ito, Cristiane Y

    2015-01-01

    This study aimed to evaluate the antifungal activity of Buchenavia tomentosa extract and bioactive compounds on six Candida species. The antimicrobial activity of extract was evaluated using standard strains and clinical isolates. Cytotoxicity was tested in order to evaluate cell damage caused by the extract. Extract was chemically characterized and the antifungal activity of its compounds was evaluated. Extract showed antifungal activity on Candida species. Candida non-albicans were more susceptible than Candida albicans. Low cytotoxicity for extract was observed. The isolated compounds presented antifungal activity at least against one Candida spp. and all compounds presented antifungal effect on Candida glabrata. Extracts from Buchenavia tomentosa showed promising antifungal activity on Candida species with low cytotoxicity. Gallic acid, corilagin and ellagic acid showed promising inhibitory activity on Candida glabrata.

  9. 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.

  10. 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.

  11. Influence of culture conditions for clinically isolated non-albicans Candida biofilm formation.

    PubMed

    Tan, Yulong; Leonhard, Matthias; Ma, Su; Schneider-Stickler, Berit

    2016-11-01

    Non-albicans Candida species have been isolated in increasing numbers in patients. Moreover, they are adept at forming biofilms. This study analyzed biofilm formation of clinically isolated non-albicans Candida, including Candida tropicalis, Candida krusei and Candida parapsilosis under the influence of different growth media (RPMI 1640, YPD and BHI) and several culture variables (inoculum concentration, incubation period and feeding conditions). The results showed that culture conditions strongly influenced non-albicans Candida species biofilm formation. YPD and BHI resulted in larger amount of biofilm formation with higher metabolic activity of biofilms. Furthermore, the growth media seems to have varying effects on adhesion and biofilm development. Growth conditions may also influence biofilm formation, which was enhanced when starting the culture with a larger inoculum, longer incubation period and using a fed-batch system. Therefore, the potential influences of external environmental factors should be considered when studying the non-albicans Candida biofilms in vitro. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. Epidemiology and antifungal susceptibility of candidemia isolates of non-albicans Candida species from cancer patients.

    PubMed

    Wu, Ping-Feng; Liu, Wei-Lun; Hsieh, Min-Han; Hii, Ing-Moi; Lee, Yu-Lin; Lin, Yi-Tsung; Ho, Mao-Wang; Liu, Chun-Eng; Chen, Yen-Hsu; Wang, Fu-Der

    2017-10-11

    Candidemia is a growing concern worldwide, and its species distribution has shifted toward non-albicans Candida in recent decades, especially in patients with malignancy. This study aimed to update the epidemiology and antifungal susceptibility of non-albicans candidemia isolates from the cancer patients. Adult cancer patients with non-albicans candidemia were recruited, and clinical data were retrospectively collected from five medical centers in Taiwan from 1 July 2011 to 30 June 2014. In vitro susceptibility was determined by the broth dilution method using a Sensititre YeastOne system and interpreted according to the guidelines of the Clinical and Laboratory Standards Institute. A total of 346 episodes of non-albicans candidemia were identified in cancer patients. Candida tropicalis was the most common species (n=145, 41.9%) and had the highest resistance rate to fluconazole (n=17, 13.9%) among all the preserved isolates, including C. tropicalis, Candida glabrata and Candida parapsilosis. A higher Charlson comorbidity index, non-albicans candidemia due to C. tropicalis, neutropenia and septic shock were independent predictors of 28-day mortality. In conclusion, the species distribution and antifungal susceptibility of non-albicans candidemia isolates in our study differed from those in Western countries, providing useful information about local epidemiology for the selection of empirical antifungal agents for cancer patients.

  13. In vitro adherence of Candida albicans isolated from patients with chronic periodontitis

    PubMed Central

    MACHADO, Adriana Gadotti; KOMIYAMA, Edson Yukio; dos SANTOS, Silvana Soléo Ferreira; JORGE, Antonio Olavo Cardoso; BRIGHENTI, Fernanda Lourenção; KOGA-ITO, Cristiane Yumi

    2011-01-01

    Adherence is considered an extremely important virulence factor in yeast. Objective The aim of this study was to analyze the adherence to epithelial cells of C. albicans isolated from patients with chronic periodontitis in comparison to healthy patients. Material and methods Candida albicans cells isolated from individuals with chronic periodontitis (n=25) and healthy controls (n=25) were included in this study. Suspensions of C. albicans (106 cells/mL) and epithelial cells (105 cells/mL) were mixed and incubated at 37ºC for 1 h. The number of yeasts adhered to 25 epithelial cells was counted. Results The number of C. albicans cells adhered to epithelial cells was statistically higher in the chronic periodontitis group than in the control group (Student's t-test, p=0.000). Conclusion The results of the present study suggest a higher Candida adherence of samples isolated from patients with chronic periodontitis. PMID:21710096

  14. Virulence of Candida albicans isolated from HIV infected and non infected individuals.

    PubMed

    Wibawa, Tri; Praseno; Aman, Abu Tholib

    2015-01-01

    Candida sp contributes 33.1 % of fungal infections among HIV patients. Among the species of the genus Candida, Candida albicans is the most frequently isolated from HIV patients. This study aimed to analyze putative virulence factors of C. albicans isolated from oral cavities of HIV infected patients and healthy individuals. Twenty isolates from HIV infected patients and fourteen from healthy individuals were analyzed for phenotypic switching, cell growth rate, hyphae formation, hemolytic activity and biofilm formation characteristics. The frequency of phenotypic switching was low in both groups. The cell growth rate of C. albicans from HIV infected patients were significantly higher than those from healthy individuals (p < 0.001). After 48 h incubation, the concentration of C. albicans isolated from HIV infected patients was 8.6 × 10(6) cells/ml while the concentration of C. albicans isolated from healthy individuals was 7.8 × 10(6) cells/ml. After 72 h incubation, the concentration of C. albicans isolated from HIV infected patients was 9.5 × 10(6) cells/ml while the concentration of C. albicans isolated from healthy individuals was 8.2 × 10(6) cells/ml. In contrast, the hemolytic activity of C. albicans isolated from healthy individuals were significantly higher compared to those from HIV infected patients (p < 0.001) at both aerobic (6 vs. 3.5 mm) and anaerobic (3.8 vs. 1.3 mm) conditions. The percentages of hyphae forming cells were higher in C. albicans collected from HIV infected patients (27.5 %) compared to the healthy individual group (14.7 %). However, this trend was not statistically significant (p = 0.1). Candida albicans isolated from HIV infected patients have similar ability to develop biofilms compared to those from healthy individuals. (OR = 4.2; 95 % CI 0.724-26.559). The virulence factors of C. albicans isolated from HIV infected patients were not significantly different from those of healthy individuals. The results

  15. 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.

  16. 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.

  17. Isolation of Candida albicans and halophilic Vibrio spp. from aquatic birds in Connecticut and Florida.

    PubMed Central

    Buck, J D

    1990-01-01

    Halophilic vibrios were recovered from feces of six types of aquatic birds (gulls, pelicans, Canada geese, swans, egrets, cormorants) from Connecticut and/or Florida shorelines. Candida albicans was isolated from gulls and Canada geese in Connecticut and from gulls and cormorants in Florida. PMID:2180374

  18. Rapid and Accurate Identification of Candida albicans Isolates by Use of PNA FISHFlow▿

    PubMed Central

    Trnovsky, Jan; Merz, William; Della-Latta, Phyllis; Wu, Fann; Arendrup, Maiken Cavling; Stender, Henrik

    2008-01-01

    We developed the simple, rapid (1 h), and accurate PNA FISHFlow method for the identification of Candida albicans. The method exploits unique in solution in situ hybridization conditions under which the cells are simultaneously fixed and hybridized. This method facilitates the accurate identification of clinical yeast isolates using two scoring techniques: flow cytometry and fluorescence microscopy. PMID:18287325

  19. Influence of cancer treatment on the Candida albicans isolated from the oral cavities of cancer patients.

    PubMed

    Ramla, Shilpa; Sharma, Vinay; Patel, Mrudula

    2016-06-01

    Cancer treatment causes mucositis and the manifestation of oral candidiasis. This study investigated the virulence properties and antifungal susceptibilities of Candida albicans isolated from cancer patients undergoing therapy. C. albicans were isolated from 49 patients on cancer treatment and 21 healthy individuals and their virulence attributes measured. A correlation was determined between the length of treatment and the fungal counts and their virulence factors. Although Candida carriage was similar in all the study groups, high quantities of C. albicans and variety of Candida were found in cancer patients. Germ tubes were produced by all the strains. Significantly high number of yeast isolated from radiotherapy and chemotherapy produced large quantities of phospholipase compared to healthy individuals (p < 0.01). The length of chemotherapy was associated with an increase in the phospholipase production (p = 0.03) by the C. albicans. Proteinase production was seen in a significant number of isolates from the radiotherapy group (p < 0.01). Type of cancer treatment had no effect. Resistance to antifungal agents was low. High quantities of phospholipase were produced by C. albicans in cancer patients on therapy which also increased with the length of chemotherapy suggesting enhanced risk of oral and systemic infection. Therefore, during treatment, prophylactic topical antifungal therapy may be considered.

  20. Isolation of a petite mutant from a histidine auxotroph of Candida albicans and its characterization.

    PubMed

    Roth-Ben Arie, Z; Altboum, Z; Berdicevsky, I; Segal, E

    1998-01-01

    Respiration-deficient (petite) mutations have been induced in various yeasts, which are categorized as petite-positive. Candida albicans was classified among the petite-negative yeasts. Since then, a few reports have appeared, describing the isolation of petite mutants in C. albicans. We report in the present study on the isolation of a petite mutant of C. albicans-SAR1. This mutant was isolated from a histidine auxotroph of C. albicans after mutagenesis with N-methyl-N'-nitro-N-nitrosoguanidine, thus our petite mutant carries a double mutation. SAR1 was characterized morphologically, biochemically and ultrastructurally. The results revealed differences from the wild type in respect to morphological, physiological and biochemical characteristics. Electron microscopy showed that the cells of the petite mutant contain only very few mitochondria that looked 'thread like' without any cristae. The significance of the mutation in the virulence of the mutant vs. that of the wild-type is being assessed.

  1. [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.

  2. Microsatellite-based genotyping of Candida albicans isolated from patients with superficial candidiasis.

    PubMed

    Shimizu, Kazue; Hattori, Hisao; Adachi, Hidesada; Oshima, Ryosuke; Horii, Toshinobu; Tanaka, Reiko; Yaguchi, Takashi; Tomita, Yasushi; Akiyama, Masashi; Kawamoto, Fumihiko; Kanbe, Toshio

    2011-01-01

    This study aimed to examine the genotype distribution of Candida albicans and the major genotypes involved in superficial candidiasis. The genotypes of C. albicans isolated from the infection sites of patients with superficial candidiasis (referred to as infection isolates) were analyzed by fragment analysis using 4 microsatellite markers (HIS3, CDC3, CAI and CAIII). Genotypes of the infection isolates were compared with those of C. albicans isolated from oral mucosa of non-candidiasis patients (referred to as oral isolates). Isolates of C. albicans showed 4 major genotypes for HIS3/CAI (" a " for 148 : 148 / 23 : 23," b " for 148 : 160 / 33 : 41," c " for 148 : 164 / 32 : 41 and " d " for 152 : 152 / 18 : 27). The genotypes " a "," b " and " d " were commonly found in oral (4.7, 8.8 and 7.6%, respectively) and infection (6.6, 9.2 and 15.4%, respectively) isolates. No isolates of genotype " c " were isolated from infection sites. The genotype " a " was found in the isolates from patients with genitalia candidiasis. Genotyping of multiple isolates from an individual patient showed that C. albicans from infection sites was genetically homogenous as compared with that of oral isolates, even in the same patient with candidiasis.

  3. 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

  4. Antifungal Activity of Bee Venom and Sweet Bee Venom against Clinically Isolated Candida albicans

    PubMed Central

    Lee, Seung-Bae

    2016-01-01

    Objectives: The purpose of this study was to investigate the antifungal effect of bee venom (BV) and sweet bee venom (SBV) against Candida albicans (C. albicans) clinical isolates. Methods: In this study, BV and SBV were examined for antifungal activities against the Korean Collection for Type Cultures (KCTC) strain and 10 clinical isolates of C. albicans. The disk diffusion method was used to measure the antifungal activity and minimum inhibitory concentration (MIC) assays were performed by using a broth microdilution method. Also, a killing curve assay was conducted to investigate the kinetics of the anti- fungal action. Results: BV and SBV showed antifungal activity against 10 clinical isolates of C. albicans that were cultured from blood and the vagina by using disk diffusion method. The MIC values obtained for clinical isolates by using the broth microdilution method varied from 62.5 μg/ mL to 125 μg/mL for BV and from 15.63 μg/mL to 62.5 μg/mL for SBV. In the killing-curve assay, SBV behaved as amphotericin B, which was used as positive control, did. The antifungal efficacy of SBV was much higher than that of BV. Conclusion: BV and SBV showed antifungal activity against C. albicans clinical strains that were isolated from blood and the vagina. Especially, SBV might be a candidate for a new antifungal agent against C. albicans clinical isolates. PMID:27280049

  5. Biotypes of Candida albicans isolated from cardiovascular system and skin surveillance cultures of hospitalized patients.

    PubMed

    Vazić-Babić, Verica; Mlinarić-Missoni, Emilija; Kalenić, Smilja

    2006-01-01

    The aim of the study was to biotype 59 isolates of Candida (C.) albicans from cardiovascular system samples (blood and intravenous catheter) and 123 isolates of the same species from skin surveillance cultures (swabs of the armpit, groins and intravenous catheter insertion sites) of hospitalized patients using the Odds and Abbott biotyping method. Biotyping of 59 isolates of C. albicans taken from the cardiovascular system samples revealed the presence of 16 biotypes. Biotype 355 was the most common biotype, accounting for 35.6% of all biotype isolates from this system. Biotyping of 123 C. albicans isolates from skin surveillance cultures detected 21 biotypes. Biotype 355 was most common, accounting for 17.9% of all biotype isolates from these samples. The two systems had 10 biotypes in common: 355, 155, 257, 305, 105, 315, 300, 015, 157, and 345. These biotypes accounted for 88.3% and 81.4% of all C. albicans biotypes isolated from the cardiovascular system and skin surveillance cultures, respectively. Biotypes 355, 155, and 257 were the biotypes most frequently shared in isolates from the two systems. These biotypes accounted for 57.7% and 43.1% of all C. albicans biotypes isolated from the cardiovascular system and skin surveillance cultures, respectively.

  6. Phenotypic and genotypic detection of Candida albicans and Candida dubliniensis strains isolated from oral mucosa of AIDS pediatric patients.

    PubMed

    Livério, Harisson Oliveira; Ruiz, Luciana da Silva; Freitas, Roseli Santos de; Nishikaku, Angela; Souza, Ana Clara de; Paula, Claudete Rodrigues; Domaneschi, Carina

    2017-04-13

    The aim of this study was to assess a collection of yeasts to verify the presence of Candida dubliniensis among strains isolated from the oral mucosa of AIDS pediatric patients which were initially characterized as Candida albicans by the traditional phenotypic method, as well as to evaluate the main phenotypic methods used in the discrimination between the two species and confirm the identification through genotypic techniques, i.e., DNA sequencing. Twenty-nine samples of C. albicans isolated from this population and kept in a fungi collection were evaluated and re-characterized. In order to differentiate the two species, phenotypic tests (Thermotolerance tests, Chromogenic medium, Staib agar, Tobacco agar, Hypertonic medium) were performed and genotypic techniques using DNA sequencing were employed for confirmation of isolated species. Susceptibility and specificity were calculated for each test. No phenotypic test alone was sufficient to provide definitive identification of C. dubliniensis or C. albicans, as opposed to results of molecular tests. After amplification and sequencing of specific regions of the 29 studied strains, 93.1% of the isolates were identified as C. albicans and 6.9% as C. dubliniensis. The Staib agar assay showed a higher susceptibility (96.3%) in comparison with other phenotypic techniques. Therefore, genotypic methods are indispensable for the conclusive identification and differentiation between these species.

  7. 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.

  8. Synthetic Organotellurium Compounds Sensitize Drug-Resistant Candida albicans Clinical Isolates to Fluconazole.

    PubMed

    Reis de Sá, L F; Toledo, F T; Gonçalves, A C; Sousa, B A; Dos Santos, A A; Brasil, P F; Duarte da Silva, V A; Tessis, A C; Ramos, J A; Carvalho, M A; Lamping, E; Ferreira-Pereira, A

    2017-01-01

    Invasive Candida albicans infections are a serious health threat for immunocompromised individuals. Fluconazole is most commonly used to treat these infections, but resistance due to the overexpression of multidrug efflux pumps is of grave concern. This study evaluated the ability of five synthetic organotellurium compounds to reverse the fluconazole resistance of C. albicans clinical isolates. Compounds 1 to 4, at <10 μg/ml, ameliorated the fluconazole resistance of Saccharomyces cerevisiae strains overexpressing the major C. albicans multidrug efflux pumps Cdr1p and Mdr1p, whereas compound 5 only sensitized Mdr1p-overexpressing strains to fluconazole. Compounds 1 to 4 also inhibited efflux of the fluorescent substrate rhodamine 6G and the ATPase activity of Cdr1p, whereas all five of compounds 1 to 5 inhibited Nile red efflux by Mdr1p. Interestingly, all five compounds demonstrated synergy with fluconazole against efflux pump-overexpressing fluconazole-resistant C. albicans clinical isolates, isolate 95-142 overexpressing CDR1 and CDR2, isolate 96-25 overexpressing MDR1 and ERG11, and isolate 12-99 overexpressing CDR1, CDR2, MDR1, and ERG11 Overall, organotellurium compounds 1 and 2 were the most promising fluconazole chemosensitizers of fluconazole-resistant C. albicans isolates. Our data suggest that these novel organotellurium compounds inhibit pump efflux by two very important and distinct families of fungal multidrug efflux pumps: the ATP-binding cassette transporter Cdr1p and the major facilitator superfamily transporter Mdr1p.

  9. Pathogenicity of Candida albicans isolates from bloodstream and mucosal candidiasis assessed in mice and Galleria mellonella.

    PubMed

    Frenkel, M; Mandelblat, M; Alastruey-Izquierdo, A; Mendlovic, S; Semis, R; Segal, E

    2016-03-01

    The working hypothesis of this study was to elucidate a possible association between the pathogenic potential of Candida albicans strains with a clinical entity, systemic versus superficial candidiasis. Specifically, we assessed the pathogenicity of two groups of clinical C. albicans isolates: isolates from bloodstream infection (S) versus isolates from vaginitis patients (M), in two experimental in vivo systems - mice and Galleria melonella, in comparison to a control strain (CBS 562). Mice and G. mellonella larvae were inoculated with CBS 562 and the different S and M isolates, and followed up for survival rate and survival time during 30 and 7 days, respectively. Candida kidney colonization of mice was assessed by histopathology and colony-forming units' enumeration. The results revealed: (1) S and M isolates had different behavior patterns in the two models and varied in different parameters; (2) no statistically significant difference in pathogenicity between S and M isolates as whole groups was noted; (3) S14 was the most virulent isolate and close to the standard strain CBS 562 in both models. This study is distinctive in its outline combining two different groups of C. albicans clinical isolates originating from two different clinical entities that were assessed in vivo concurrently in two models. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  10. Isolation of a gene encoding a putative polyamine transporter from Candida albicans, GPT1.

    PubMed

    McNemar, M D; Gorman, J A; Buckley, H R

    2001-04-01

    A gene encoding a transport protein from the pathogenic yeast, Candida albicans, has been isolated during a complementation experiment utilizing an ornithine decarboxylase-negative (spe1 Delta) strain of Saccharomyces cerevisiae. This gene restores gamma-aminobutyric acid (GABA) transport to a GABA transport-negative mutant of S. cerevisiae and encodes a protein which putatively allows transport of one or more of the polyamines. We have assigned the name GPT1 (GABA/polyamine transporter) to this gene.

  11. Candida albicans and non-C. albicans Candida species: comparison of biofilm production and metabolic activity in biofilms, and putative virulence properties of isolates from hospital environments and infections.

    PubMed

    Ferreira, A V; Prado, C G; Carvalho, R R; Dias, K S T; Dias, A L T

    2013-04-01

    Candida albicans and, more recently, non-C. albicans Candida spp. are considered the most frequent fungi in hospitals. This study analyzed Candida spp. isolates and compared the frequency of different species, that is, C. albicans and non-C. albicans Candida spp., and the origins of isolates, that is, from hospital environments or infections. Yeast virulence factors were evaluated based on biofilm production and metabolic activity. Hemolysin production and the antifungal susceptibility profiles of isolates were also evaluated. Candida spp. were highly prevalent in samples collected from hospital environments, which may provide a reservoir for continuous infections with these yeasts. There were no differences in the biofilm productivity levels and metabolic activities of the environmental and clinical isolates, although the metabolic activities of non-C. albicans Candida spp. biofilms were greater than those of the C. albicans biofilms (p < 0.05). Clinical samples had higher hemolysin production (p < 0.05) and lower susceptibility to fluconazole (p < 0.05). Non-C. albicans Candida spp. predominated in samples collected from hospital environments and infections (p < 0.05). These species had a lower susceptibility to fluconazole and amphotericin B, and their biofilms had higher metabolic activities than those produced by C. albicans, which may explain the increased incidence of fungal infections with these yeasts during recent years.

  12. Genotypes of Candida albicans isolated from healthy individuals and their distribution in patients with oral candidiasis.

    PubMed

    Takagi, Yuki; Fukano, Hideo; Shimozato, Kazuo; Tanaka, Reiko; Horii, Toshinobu; Kawamoto, Fumihiko; Kanbe, Toshio

    2013-12-01

    For the study of Candida albicans genotypes involved in development of candidiasis, Candida albicans isolates were collected from healthy volunteers and patients with oral candidiasis and genotyped on the basis of 25S rDNA and microsatellite polymorphisms. In the microsatellite analysis using two microsatellite markers (CDC3 and CAI), 63 healthy volunteer isolates were classified into 35 genotypes (allelic relations to CDC3 alleles 1:2/CAI alleles 1:2), among which genotypes II (115:119/23:23), III (115:123/18:27), and V (123:127/32:41) were found at frequencies of 12.7%, 7.9%, and 7.9%, respectively. In 68 oral candidiasis isolates classified into 39 genotypes, genotypes II and III were identified in 4.4% and 20.6% of the isolates, respectively. The frequency of genotype III was higher in the candidiasis isolates than in the healthy isolates (p < 0.05). These results suggest that genotype III C. albicans assigned by CDC3/CAI is related to the development of oral candidiasis.

  13. Effects of antifungal agents in sap activity of Candida albicans isolates.

    PubMed

    Costa, Carolina Rodrigues; Jesuíno, Rosália Santos Amorim; de Aquino Lemos, Janine; de Fátima Lisboa Fernandes, Orionalda; Hasimoto e Souza, Lúcia Kioko; Passos, Xisto Sena; do Rosário Rodrigues Silva, Maria

    2010-02-01

    Some antifungal agents have shown to exert effects on expression of virulent factors of Candida as the production of secretory aspartyl proteinase (Sap). In this study, we sought to determine and to compare the influence of fluconazole and voriconazole in proteinase activity of this microorganism. Thirty-one isolates obtained from oral mucosa of human immunodeficiency virus positive (HIV) patients were used in this study. The minimal inhibitory concentrations (MIC) of fluconazole and voriconazole were determined using the broth microdilution method with RPMI 1640 medium and with yeast carbon base-bovine serum albumin (YCB-BSA) medium. The Sap activity following by digestion of BSA as substrate was determined for four Candida albicans strains arbitrarily chosen according to susceptibility (susceptible or resistant) to fluconazole or voriconazole. Besides, the SAP1 to SAP7 genes were screened by PCR for the same isolates that were determined by the Sap activity. In vitro susceptibility testing using the two media presented similar MIC values. Increased Sap activity was observed in resistant isolates on presence of drugs, but the Sap activity by susceptible isolates to azoles showed different behavior on the presence of drug. We detected the presence of SAP1 to SAP7 genes from all susceptible or resistant C. albicans isolates. The present study provides important data about the proteinase activity and the presence of genes of SAP family in fluconazole and voriconazole susceptible or resistant C. albicans isolates.

  14. Molecular typing of Candida albicans strains isolated from denture wearers by repetitive sequence-based PCR.

    PubMed

    Abaci, O; Haliki-Uztan, A; Ozturk, B; Toksavul, S; Ulusoy, M; Boyacioglu, H

    2011-02-01

    Long-term use of prosthesis is the most important risk factor for the colonization of Candida species on the mucosal surfaces, which can lead to the development of denture-related stomatitis (DRS). Some individuals wearing prosthesis develop DRS and others do not. C. albicans strains isolated from both groups were genotypically compared. The purpose of this study was to determine whether the strain causing prosthesis stomatitis was different from the other strains genotypically. The study included 90 individuals wearing different prostheses and 20 control individuals with natural teeth. In the study 109 C. albicans strains were used which were isolated from the saliva samples and the mucosal surfaces of the tongues and palates of 51 individuals and then defined phenotypically. Phenotypic diagnosis of the isolates was genotypically verified by using species-specific PCR. For molecular typing, repetitive extragenic palindromic sequence polymerase chain reaction (REP-PCR) was employed. The results of the study revealed that REP-PCR had the capability to separate 109 C. albicans strains and six reference strains into 44 genotypes. Whereas C. albicans strains showed heterogenic distribution, C. albicans strains isolated from the individuals suffering from prosthesis stomatitis showed no specific genotypes. REP-PCR is a simple, fast and low-cost method and helped work on a great number of samples.

  15. [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.

  16. Effects of Rosmarinus officinalis essential oil on germ tube formation by Candida albicans isolated from denture wearers.

    PubMed

    Gauch, Lurdete Maria Rocha; Silveira-Gomes, Fabíola; Esteves, Renata Antunes; Pedrosa, Simone Soares; Gurgel, Ely Simone Cajueiro; Arruda, Alberto Cardoso; Marques-da-Silva, Silvia Helena

    2014-01-01

    The aim of this study was to investigate the effects of Rosmarinus officinalis essential oil on germ tube formation by Candida albicans isolated from denture wearers. Ten C. albicans isolates recovered from denture wearers were tested using 10% fetal bovine serum with or without 4% R. officinalis essential oil. The essential oil from R. officinalis completely inhibited germ tube formation in the investigated C. albicans isolates. The results demonstrate that the essential oil of R. officinalis modulates C. albicans pathogenicity through its primary virulence factor (i.e., germ tube formation was suppressed).

  17. 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.

  18. Virulence factors of Candida albicans isolates from the oral cavities of HIV-1-positive patients.

    PubMed

    Menezes, Tatiany O A; Gillet, Luciana C S; Menezes, Sílvio A F; Feitosa, Rosimar N M; Ishak, Marluísa O G; Ishak, Ricardo; Marques-da-Silva, Sílvia H; Vallinoto, Antonio C R

    2013-06-01

    The present study assessed the phenotypic aspects of oral-cavity Candida albicans isolates from 300 HIV-1- positive patients, relating the most commonly investigated virulence factors (enzyme typing and germ-tube formation) to the most common morphotypes. The samples were seeded into specific media for isolation and subsequent identification using the automated Vitek 2 system. The following assays were performed for phenotypic characterization: morphotyping, germ-tube formation and enzyme typing. Out of 300 collected samples, 144 tested positive for yeasts of the Candida genus, 98 (32.7 %) of which were identified as C. albicans. The latter samples were attributed to seven different morphotypes; the three most common morphotypes were 7208 (49 %), 7308 (14.3 %) and 3208 (13.3 %). All of the C. albicans isolate samples formed germ tubes and produced the enzymes proteinase and phospholipase, with an activity classified as intermediate to high. Due to the identification of virulence factors among the analyzed samples, monitoring of HIV-1-positive patients colonized by different morphotypes must be established because these morphotypes are extremely pathogenic and can trigger severe fungal infections.

  19. 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. Copyright © 2015 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

  20. 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.

  1. 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

  2. Enrichment of Multilocus Sequence Typing Clade 1 with Oral Candida albicans Isolates in Patients with Untreated Periodontitis

    PubMed Central

    McManus, Brenda A.; Maguire, Rory; Cashin, Phillipa J.; Claffey, Noel; Flint, Stephen; Abdulrahim, Mohammed H.

    2012-01-01

    This study investigated the prevalence and cell density of Candida species in periodontal pockets, healthy subgingival sites, and oral rinse samples of patients with untreated periodontitis. Twenty-one periodontitis patients underwent sampling at two periodontitis sites, and 19/21 of these patients underwent sampling at one periodontally healthy site. Both paper point and curette sampling techniques were employed. The periodontitis patients and 50 healthy subjects were also sampled by oral rinse. Candida isolates were recovered on CHROMagar Candida medium, and representative isolates were identified. Candida spp. were recovered from 10/21 (46.7%) periodontitis patients and from 16/50 (32%) healthy subjects. C. albicans predominated in both groups and was recovered from all Candida-positive subjects. Candida-positive periodontitis patients yielded Candida from periodontal pockets with average densities of 3,528 and 3,910 CFU/sample from curette and paper point samples, respectively, and 1,536 CFU/ml from oral rinse samples. The majority (18/19) of the healthy sites sampled from periodontitis patients were Candida negative. The 16 Candida-positive healthy subjects yielded an average of 279 CFU/ml from oral rinse samples. C. albicans isolates were investigated by multilocus sequence typing (MLST) to determine if specific clonal groups were associated with periodontitis. MLST analysis of 31 C. albicans isolates from periodontitis patients yielded 19 sequence types (STs), 13 of which were novel. Eleven STs belonged to MLST clade 1. In contrast, 16 C. albicans isolates from separate healthy subjects belonged to 16 STs, with 4 isolates belonging to clade 1. The distributions of STs between both groups were significantly different (P = 0.04) and indicated an enrichment of C. albicans isolates in periodontal pockets, which warrants a larger study. PMID:22875886

  3. 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. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Evaluation of virulence factors of Candida albicans isolated from HIV-positive individuals using HAART.

    PubMed

    de Paula Menezes, Ralciane; de Melo Riceto, Érika Bezerra; Borges, Aércio Sebastião; de Brito Röder, Denise Von Dolingër; dos Santos Pedroso, Reginaldo

    2016-06-01

    The colonization by Candida species is one of the most important factors related to the development of oral candidiasis in HIV-infected individuals. The aim of the study was to evaluate and discuss the phospholipase, proteinase, DNAse and haemolytic activities of Candida albicans isolated from the oral cavity of HIV individuals with high efficiency antiretroviral therapy. Seventy-five isolates of C. albicans obtained from saliva samples of patients with HIV and 41 isolates from HIV-negative individuals were studied. Haemolytic activity was determined in Sabouraud dextrose agar plates containing 3% glucose and 7% sheep red cells. Culture medium containing DNA base-agar, egg yolk, and bovine albumin were used to determine DNase, phospholipase and proteinase activities, respectively. All isolates from the HIV patients group had haemolytic activity, 98% showed phospholipase activity, 92% were positive for proteinase and 32% DNAse activity. Regarding the group of indivídios HIV negative, all 41 isolates presented hemolytic activity, 90.2% showed phospholipase and proteinase activity and 12.2% were positive for DNAse. The phospholipase activity was more intense for the group of HIV positive individuals. DNase production was more frequently observed in the group of HIV-positive individuals. The percentage of isolates having DNAse activity was also significantly different between the groups of patients not using any antiretroviral therapy, those using transcriptase inhibitors and those using transcriptase inhibitor and protease inhibitor in combination. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Antifungal susceptibility and molecular typing of 115 Candida albicans isolates obtained from vulvovaginal candidiasis patients in 3 Shanghai maternity hospitals.

    PubMed

    Ying, Chunmei; Zhang, Hongju; Tang, Zhenhua; Chen, Huifen; Gao, Jing; Yue, Chaoyan

    2016-05-01

    In our multicenter study, we studied the distribution of Candida species in vulvovaginal candidiasis patients and investigated antifungal susceptibility profile and genotype of Candida albicans in vaginal swab. A total of 115 Candida albicans strains were detected in 135 clinical isolates. Minimum inhibitory concentration determinations showed that 83% and 81% of the 115 Candida albicans strains were susceptible to fluconazole and voriconazole. Randomly amplified polymorphic DNA analysis (RAPD) was applied to identify clonally related isolates from different patients at the local level. All tested strains were classified into genotype A (77.4%), genotype B (18.3%), and genotype C (4.3%). Genotype A was further classified into five subtypes and genotype B into two subtypes.Candida albicans was the dominant pathogen of vulvovaginal candidiasis, the majority belonging to genotype A in this study. Exposure to azoles is a risk factor for the emergence of azole resistance among Candida albicans isolated from VVC patients. © The Author 2015. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  6. Assessment of antifungal activity of herbal and conventional toothpastes against clinical isolates of Candida albicans

    PubMed Central

    Adwan, Ghaleb; Salameh, Yousef; Adwan, Kamel; Barakat, Ali

    2012-01-01

    Objective To detect the anticandidal activity of nine toothpastes containing sodium fluoride, sodium monofluorophosphate and herbal extracts as an active ingredients against 45 oral and non oral Candida albicans (C. albicans) isolates. Methods The antifungal activity of these toothpaste formulations was determined using a standard agar well diffusion method. Statistical analysis was performed using a statistical package, SPSS windows version 15, by applying mean values using one-way ANOVA with post-hoc least square differences (LSD) method. A P value of less than 0.05 was considered significant. Results All toothpastes studied in our experiments were effective in inhibiting the growth of all C. albicans isolates. The highest anticandidal activity was obtained from toothpaste that containing both herbal extracts and sodium fluoride as active ingredients, while the lowest activity was obtained from toothpaste containing sodium monofluorophosphate as an active ingredient. Antifungal activity of Parodontax toothpaste showed a significant difference (P< 0.001) against C. albicans isolates compared to toothpastes containing sodium fluoride or herbal products. Conclusions In the present study, it has been demonstrated that toothpaste containing both herbal extracts and sodium fluoride as active ingredients are more effective in control of C. albicans, while toothpaste that containing monofluorophosphate as an active ingredient is less effective against C. albicans. Some herbal toothpaste formulations studied in our experiments, appear to be equally effective as the fluoride dental formulations and it can be used as an alternative to conventional formulations for individuals who have an interest in naturally-based products. Our results may provide invaluable information for dental professionals. PMID:23569933

  7. Biotypes of oral Candida albicans isolates in a Tanzanian child population.

    PubMed

    Matee, M I; Samaranayake, L P; Scheutz, F; Simon, E; Lyamuya, E F; Mwinula, J

    1996-09-01

    Although biotypes of Candida albicans from adult populations, especially in the West, have been described, there are no data either from a child population, or from the African continent. Hence a total of 200 oral C. albicans isolates from Tanzanian children aged 6-24 months were biotyped using two commercially available API micromethod kit systems and a boric acid resistance test. The predominant biotypes, which comprised two thirds of the organisms isolated, were J1S (19.5%), A1S (16.0%), J1R (14.5%), A1R (9.5%) and P1R (7.5%). In total, 16 new biotypes comprising 44 (22%) isolates which have not hitherto been described were found in this Tanzanian population and, of these, the P1R biotype predominated with 15 (7.5%) isolates. There was no significant association between predominant biotypes (with clusters > or = 15 isolates) and age, gender, breast feeding and malnutrition. These data indicate that the biotype profile of C. albicans isolates may differ in paediatric and adult populations, and/or global distribution of various subtypes of this common opportunistic pathogen.

  8. Systemic neonatal candidosis: the karyotyping of Candida albicans strains isolated from neonates and health-workers.

    PubMed

    Ben Abdeljelil, J; Ben Saida, N; Saghrouni, F; Fathallah, A; Boukadida, J; Sboui, H; Ben Said, M

    2010-01-01

    Candida albicans has become an important cause of nosocomial infections in neonatal intensive care units (NICUs). The aim of the present study was to compare C. albicans strains isolated from neonates (NN) suffering from systemic candidosis and from nurses in order to determine the relatedness between NN and health workers' strains. Thirty-one C. albicans strains were isolated from 18 NN admitted to the NICU of the neonatology service of Farhat Hached Hospital of Sousse, Tunisia and suffering from systemic candidosis, together with five strains recovered from nurses suffering from C. albicans onychomycosis. Two additional strains were tested, one from an adult patient who developed a systemic candidosis and the second from an adult with inguinal intertrigo. All strains were karyotyped by pulsed-field gel electrophoresis (PFGE) with a CHEF-DR II system. Analysis of PFGE patterns yielded by the 38 strains tested led to the identification of three pulsotypes that were designated I, II and III, and consisted of six chromosomal bands with a size ranging from 700 to >2500 kbp. The most widespread was the pulsotype I, which was shared by 17 NN and the five nurses' strains. The identity between NN and nurses' strains is very suggestive of a nosocomial acquisition from health-workers.

  9. Antimicrobial activity of Buchenavia tetraphylla against Candida albicans strains isolated from vaginal secretions.

    PubMed

    Cavalcanti Filho, José Robson Neves; Silva, Tiago Fonseca; Nobre, Woah Queiroz; Oliveira de Souza, Larissa Isabela; Silva E Silva Figueiredo, Cristiane Santos; Figueiredo, Regina Celia Bressan Queiroz de; de Gusmão, Norma Buarque; Silva, Márcia Vanusa; Nascimento da Silva, Luís Cláudio; Correia, Maria Tereza Dos Santos

    2017-12-01

    Buchenavia tetraphylla (Aubl.) RA Howard (Combretaceae: Combretoideae) is an ethnomedicinal plant with reported antifungal action. This study evaluates the antimicrobial activity of B. tetraphylla leaf extracts against clinical isolates of Candida albicans. The morphological alterations, combinatory effects with fluconazole and the cytotoxicity of the active extract were analyzed. Extracts were obtained using different solvents (hexane: BTHE; chloroform: BTCE; ethyl acetate: BTEE; and methanol: BTME). Antimicrobial activity was determined by the broth microdilution method using nine strains of C. albicans isolated from vaginal secretions and one standard strain (UFPEDA 1007). All extracts showed anti-C. albicans activity, including against the azole-resistant strains. The MIC values ranged from 156 to 2500 μg/mL for the BTHE; 156 to 1250 μg/mL for the BTCE; 625 to 1250 μg/mL for the BTME and 625 μg/mL to 2500 μg/mL for the BTEE. BTME showed the best anti-C. albicans activity. This extract demonstrated additive/synergistic interactions with fluconazole. Scanning electron microscopy analysis suggested that the BTME interferes with the cell division and development of C. albicans. BTME showed IC50 values of 981 and 3935 μg/mL, against J774 macrophages and human erythrocytes, respectively. This extract also enhanced the production of nitric oxide by J774 macrophages. Buchenavia tetraphylla methanolic extract (BTME) is a great source of antimicrobial compounds that are able to enhance the action of fluconazole against different C. albicans strains; this action seems related to inhibition of cell division.

  10. Cyclosporine A decreases the fluconazole minimum inhibitory concentration of Candida albicans clinical isolates but not biofilm formation and cell growth.

    PubMed

    Wibawa, T; Nurrokhman; Baly, I; Daeli, P R; Kartasasmita, G; Wijayanti, N

    2015-03-01

    Among the genus Candida, Candida albicans is the most abundant species in humans. One of the virulent factors of C. albicans is its ability to develop biofilm. Biofilm forming microbes are characterized by decreasing of its susceptibility to antibiotics and antifungal. The fungicidal effect of fluconazole may be enhanced by cyclosporine A in laboratory engineered C. albicans strains. The aim of this work is to analyze the synergistic effect of cyclosporine A with fluconazole in C. albicans clinical isolates and the effect of cycolsporine A alone in the biofilm formation. Six fluconazole resistant and six sensitive C. albicans clinical isolates were analyzed for its minimum inhibitory concentration (MICs), biofilm formation, and cell growths. A semi-quantitative XTT [2,3-bis(2-methoxy-4-nitro-5- sulfo-phenyl)-2H-tetrazolium-5-carboxanilide] reduction assay was conducted to measure the biofilm formation. Cyclosporine A has synergistic effect with fluconazole that was shown by decreasing MICs of both fluconazole resistant and sensitive C. albicans clinical isolates. However, cyclosporine A alone did not influence the biofilm formation and cell growth of both fluconazole resistant and sensitive C. albicans clinical isolates. These results indicated that cyclosporine A might be a promising candidate of adjuvant therapy for fluconazole against both fluconazole resistant and sensitive C. albicans clinical isolates.

  11. The efficacy of disinfectants on abattoirs’ Candida albicans isolates in Niger Delta region

    PubMed Central

    Olorode, Oluwayemisi A

    2012-01-01

    This study was conducted to evaluate the antimicrobial activities of common disinfectants- these are (parachlorometaxylenol) dettol, savlon purit and jik (sodium hypochlorite) on  Candida albicans isolated from displaying and cutting tables in five different abattoirs in Port Harcourt (Niger Delta region); the abattoirs include Trans Amadi, Agip, Woji, Rumuokoro, and Rumuodara. This research was carried out between January 2005 and June 2006. Swab samples were collected from abattoirs cutting tables with sterile swab sticks and immediately transferred and cultured in the laboratory on a selective medium Sabouraud Dextrose Agar (SDA). The disinfectants’ concentrations were prepared at 10%, 20%, 40%, and 70%, in triplicates and the mean values calculated. 0.5 Mc Farland turbidity method of standardization and Agar diffusion method were used for disinfectants testing of the isolates. Statistical analysis of the data showed no significant difference in the effectiveness of these disinfectants at (p<0.05). In conclusion, this study has shown that savlon and dettol were the most potent antimicrobial agents at 10% concentration on  Candida albicans isolates when compared with purit and jik in this study, hence they are good sanitizing agents to be applied on the abattoirs cutting tables, before meat products can be displayed for sale. PMID:24358834

  12. The efficacy of disinfectants on abattoirs' Candida albicans isolates in Niger Delta region.

    PubMed

    Olorode, Oluwayemisi A; Okpokwasli, G Chijioke

    2012-01-01

    This study was conducted to evaluate the antimicrobial activities of common disinfectants- these are (parachlorometaxylenol) dettol, savlon purit and jik (sodium hypochlorite) on  Candida albicans isolated from displaying and cutting tables in five different abattoirs in Port Harcourt (Niger Delta region); the abattoirs include Trans Amadi, Agip, Woji, Rumuokoro, and Rumuodara. This research was carried out between January 2005 and June 2006. Swab samples were collected from abattoirs cutting tables with sterile swab sticks and immediately transferred and cultured in the laboratory on a selective medium Sabouraud Dextrose Agar (SDA). The disinfectants' concentrations were prepared at 10%, 20%, 40%, and 70%, in triplicates and the mean values calculated. 0.5 Mc Farland turbidity method of standardization and Agar diffusion method were used for disinfectants testing of the isolates. Statistical analysis of the data showed no significant difference in the effectiveness of these disinfectants at (p<0.05). In conclusion, this study has shown that savlon and dettol were the most potent antimicrobial agents at 10% concentration on  Candida albicans isolates when compared with purit and jik in this study, hence they are good sanitizing agents to be applied on the abattoirs cutting tables, before meat products can be displayed for sale.

  13. Expression of SAP5 and SAP9 in Candida albicans biofilms: comparison of bloodstream isolates with isolates from other sources.

    PubMed

    Joo, Min Young; Shin, Jong Hee; Jang, Hee-Chang; Song, Eun Song; Kee, Seung Jung; Shin, Myung Geun; Suh, Soon Pal; Ryang, Dong Wook

    2013-11-01

    Secreted aspartic proteases (Sap), encoded by a family of 10 SAP genes, are key virulence determinants in Candida albicans. Although biofilm-associated bloodstream infections (BSIs) are frequently caused by C. albicans, SAP gene expression in C. albicans biofilms formed by BSI isolates has not been evaluated. We compared the expression of two SAP genes, SAP5 and SAP9, in C. albicans biofilms formed by BSI isolates with those formed by isolates from other body sites. Sixty-three C. albicans isolates were analyzed, comprising 35 BSI isolates and 28 from other sites. A denture-strip biofilm model was used, and expression of the two SAP genes was quantified by real-time RT-PCR during planktonic or biofilm growth. Mean SAP5 expression levels of the BSI isolates were 3.59-fold and 3.86-fold higher in 24-h and 48-h biofilms, respectively, than in planktonic cells. These results did not differ from those for isolates from other sites (2.71-fold and 2.8-fold for 24-h and 48-h biofilms, respectively). By contrast, mean SAP9 expression during biofilm formation was higher in BSI isolates (2.89-fold and 3.29-fold at 24 and 48 h, respectively) than in isolates from other sites (1.27-fold and 1.32-fold at 24 and 48 h, respectively; both, P < 0.001). These results show, for the first time, that both SAP5 and SAP9 are upregulated in C. albicans biofilms formed by BSI isolates, and that BSI isolates may have a greater capacity to express SAP9 under biofilm conditions than isolates from other sites.

  14. Biotypes of oral Candida albicans isolated from AIDS patients and HIV-free subjects in Thailand.

    PubMed

    Teanpaisan, R; Nittayananta, W; Chongsuvivatwong, V

    2000-05-01

    This study was conducted to examine biotypes and antifungal susceptibility patterns of oral Candida albicans isolated from HIV-infected patients, HIV-free patients with candidiasis and healthy subjects. All isolates were biotyped using a typing system based on enzyme profiles, carbohydrate assimilation patterns and boric acid resistance. Thirty-eight biotypes were found amongst 218 oral C. albicans isolates. The major biotype found was A1S, which accounted for 32.6% of all isolates, and this biotype was the most common in all groups. There was a greater variety of biotypes of C. albicans in the HIV-infected group than in the other groups; however, there was no statistically significant difference between the groups. The minimum inhibitory concentrations (MICs) of a total of 118 isolates were determined for amphotericin B and for ketoconazole using the National Committee for Clinical Laboratory Standards (NCCLS) broth macrodilution method and the E-test. When the antifungal susceptibility patterns among the groups were compared, a statistically significant difference was found only with amphotericin B. The median MIC of amphotericin B in the HIV-infected group was higher than in the healthy group (P=0.013, NCCLS method; P=0.002, E-test). However, this difference in sensitivity was not restricted to any sub-type investigated. Our results showed that the biotype patterns of C. albicans isolates that colonize HIV-infected patients are similar to those of HIV-free subjects, and there is no relationship between antifungal susceptibility patterns and the biotypes.

  15. Outcome of experimental rat vaginitis by Candida albicans isolates with different karyotypes.

    PubMed

    Tavanti, Arianna; Campa, Daniele; Arancia, Silvia; Hensgens, Lambert A M; de Bernardis, Flavia; Senesi, Sonia

    2010-01-01

    Candida albicans isolates with different genomic background, designed as b and c karyotypes, have been previously shown to differentially modulate their response to macrophage candidacidal activity. While b-type isolates were susceptible to intracellular killing, strains with c karyotype survived upon internalization and were able to replicate inside macrophages. Furthermore, it was also shown that c type strains escape microglial cell mediated growth inhibition, suggesting that these strains form a more virulent cluster. In this report, the pathogenicity exerted by C. albicans isolates with b and c karyotypes was analyzed in vivo using a model of experimental rat vaginitis. Although both types induced infection, c-type-infected animals suffered from more persistent vaginitis, confirming the higher virulence potential the c karyotype exerted in vivo. The analysis of fungal cells recovered from vaginal fluids of infected animals indicated that c-type was more prone to undergo morphogenesis and to express SAP2 than b-type; these different traits may account for the differences observed in the outcome of experimental rodent vaginitis induced by the two C. albicans karyotypes. Copyright 2010 Elsevier Ltd. All rights reserved.

  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. 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

  18. Molecular mechanisms associated with Fluconazole resistance in clinical Candida albicans isolates from India.

    PubMed

    Mane, Arati; Vidhate, Pallavi; Kusro, Chanchal; Waman, Vaishali; Saxena, Vandana; Kulkarni-Kale, Urmila; Risbud, Arun

    2016-02-01

    Resistance to azole antifungals is a significant problem in Candida albicans. An understanding of resistance at molecular level is essential for the development of strategies to tackle resistance and rationale design of newer antifungals and target-based molecular approaches. This study presents the first evaluation of molecular mechanisms associated with fluconazole resistance in clinical C.albicans isolates from India. Target site (ERG11) alterations were determined by DNA sequencing, whereas real-time PCRs were performed to quantify target and efflux pump genes (CDR1, CDR2, MDR1) in 87 [Fluconazole susceptible (n = 30), susceptible-dose dependent (n = 30) and resistant (n = 27)] C.albicans isolates. Cross-resistance to fluconazole, ketoconazole and itraconazole was observed in 74.1% isolates. Six amino acid substitutions were identified, including 4 (E116D, F145L, E226D, I437V) previously reported ones and 2 (P406L, Q474H) new ones. CDR1 over-expression was seen in 77.7% resistant isolates. CDR2 was exclusively expressed with CDR1 and their concomitant over-expression was associated with azole cross-resistance. MDR1 and ERG11 over-expression did not seem to be associated with resistance. Our results show that drug efflux mediated by Adenosine-5'-triphosphate (ATP)-binding cassette transporters, especially CDR1 is the predominant mechanism of fluconazole resistance and azole cross-resistance in C. albicans and indicate the need for research directed towards developing strategies to tackle efflux mediated resistance to salvage azoles. © 2015 Blackwell Verlag GmbH.

  19. The Evaluation of the virulence factors of clinical Candida isolates and the anti-biofilm activity of Elettaria cardamomum against multi-drug resistant Candida albicans

    PubMed Central

    Vijayalakshmi, P; Thenmozhi, S; Rajeswari, P

    2016-01-01

    Background and Purpose: Today, treatment of life-threatening fungal infections, caused by Candida species, has become a major problem. In the present study, we aimed to evaluate the antifungal susceptibility patterns of different clinical Candida isolates, determine the virulence factors in multi-drug resistant (MDR) Candida species, and assess the anti-biofilm activity of Elettaria cardamomum against MDR Candida species. Materials and Methods: A total of 202 isolates from different Candida species were obtained from three governmental hospitals in Senthamangalam, Tiruchengode, and Namakkal, Tamil Nadu, India. The isolates were identified, using conventional methods. Candida species were tested for virulence factors such as biofilm, protease, and phospholipase activity. The minimum inhibitory concentration (MIC) of Elettaria cardamomum against MDR biofilm-forming C. albicans was determined, using plate and tube methods. Results: The identified Candida isolates (n=202) were C. albicans (74/202), C. glabrata (53/202), C. parapsilosis (44/202), C. tropicalis (15/202), and C. dubliniensis (16/202). The isolates were subjected to antifungal susceptibility testing and the virulence factors were determined. In terms of biofilm production, non-C. albicans species such as C. dubliniensis showed 75% activity. Also, regarding protease activity, C. parapsilosis (75%) showed the highest percentage of protease production. In addition, Candida species showed strong positivity for phospholipase activity (62.87%). In the MIC method, the acetonic extract completely inhibited biofilm production at a concentration of 125 µl (56.25 µg). In comparison with the ethanolic extract, the acetonic extract showed major activity against biofilm production. Conclusion: Based on the findings, pathogenic C. albicans species were inhibited by the ethanolic and acetonic extracts of E. cardamomum. In recent years, MDR and biofilm-forming pathogenic Candida species have been increasingly detected in

  20. The Evaluation of the virulence factors of clinical Candida isolates and the anti-biofilm activity of Elettaria cardamomum against multi-drug resistant Candida albicans.

    PubMed

    Vijayalakshmi, P; Thenmozhi, S; Rajeswari, P

    2016-06-01

    Today, treatment of life-threatening fungal infections, caused by Candida species, has become a major problem. In the present study, we aimed to evaluate the antifungal susceptibility patterns of different clinical Candida isolates, determine the virulence factors in multi-drug resistant (MDR) Candida species, and assess the anti-biofilm activity of Elettaria cardamomum against MDR Candida species. A total of 202 isolates from different Candida species were obtained from three governmental hospitals in Senthamangalam, Tiruchengode, and Namakkal, Tamil Nadu, India. The isolates were identified, using conventional methods. Candida species were tested for virulence factors such as biofilm, protease, and phospholipase activity. The minimum inhibitory concentration (MIC) of Elettaria cardamomum against MDR biofilm-forming C. albicans was determined, using plate and tube methods. The identified Candida isolates (n=202) were C. albicans (74/202), C. glabrata (53/202), C. parapsilosis (44/202), C. tropicalis (15/202), and C. dubliniensis (16/202). The isolates were subjected to antifungal susceptibility testing and the virulence factors were determined. In terms of biofilm production, non-C. albicans species such as C. dubliniensis showed 75% activity. Also, regarding protease activity, C. parapsilosis (75%) showed the highest percentage of protease production. In addition, Candida species showed strong positivity for phospholipase activity (62.87%). In the MIC method, the acetonic extract completely inhibited biofilm production at a concentration of 125 µl (56.25 µg). In comparison with the ethanolic extract, the acetonic extract showed major activity against biofilm production. Based on the findings, pathogenic C. albicans species were inhibited by the ethanolic and acetonic extracts of E. cardamomum. In recent years, MDR and biofilm-forming pathogenic Candida species have been increasingly detected in clinical settings. Therefore, herbal derivatives might contribute

  1. [Investigation of the expression levels of efflux pumps in fluconazole-resistant Candida albicans isolates].

    PubMed

    Gulat, Sinem; Doluca Dereli, Mine

    2014-04-01

    Widespread and repeated use of fluconazole in the prophylaxis and therapy resulted in resistance among Candida strains. Investigation of the expression of efflux pump encoding genes was aimed in fluconazole-resistant and -susceptible C.albicans isolates in order to determine the role of this mechanism in fluconazole resistance. Five fluconazole-resistant, six -susceptible and four trailing effect showing susceptible C.albicans isolates were included in the study. The MIC values of fluconazole and other antifungal agents were determined by the microdilution method. The fluconazole MIC values of the fluconazole-resistant strains were also studied by E-test performed on yeast extract peptone dextrose agar with and without cyclosporin A. The expression levels of CDR1, CDR2 and MDR1 transcripts were determined by real-time PCR method. The expression of these genes was normalized with their ACT1 levels and compared with the fluconazole-susceptible C.albicans ATCC 14053 strain. It was detected that all strains were susceptible to amphotericin B and all except one strain were also susceptible to clotrimazole. Three out of five fluconazole-resistant strains and three out of four trailing effect showing susceptible strains were resistant to 5-flucytosine, and all except one susceptible strains were found as intermediate to 5-flucytosine. All except one fluconazole-resistant strains were determined as resistant to itraconazole and ketoconazole, and had miconazole MIC values of ≥ 64 µg/ml. All fluconazole-susceptible isolates were detected to be susceptible to ketoconazole and dose dependent susceptible to itraconazole. Fluconazole-resistant and -susceptible strains were determined as susceptible to voriconazole. Out of five fluconazole-resistant isolates, two strains overexpressed high levels and three strains overexpressed mild levels of CDR1/2; one strain overexpressed high levels and three strains overexpressed low levels of MDR1 in comparison to C.albicans ATCC 14053

  2. Biotypes of oral Candida albicans isolates in human immunodeficiency virus-infected patients from diverse geographic locations.

    PubMed

    Tsang, P C; Samaranayake, L P; Philipsen, H P; McCulloug, M; Reichart, P A; Schmidt-Westhausen, A; Scully, C; Porter, S R

    1995-01-01

    Oral Candida albicans isolates from HIV-infected individuals in Hong Kong, Australia, Germany and England were characterised using a biotyping system based on enzyme profiles, carbohydrate assimilation patterns and boric acid resistance of the yeasts. A total of 44 biotypes were found amongst the 117 oral C. albicans isolates examined. The major biotype A1R accounted for 17.9% of all isolates while the second commonest biotype was A1S (11.1% of isolates). Whereas these two biotypes were isolated from all the regions studied, there were a number of other biotypes unique to individual countries. The data indicate that there are many different sub-strains of oral C. albicans in HIV-infected patients, some of which are globally prevalent. However, further work is required to ascertain the diversity of oral C. albicans biotypes, if any, in health and disease.

  3. Candida species distribution, genotyping and virulence factors of Candida albicans isolated from the oral cavity of kidney transplant recipients of two geographic regions of Brazil

    PubMed Central

    2014-01-01

    Background Candida albicans is a diploid yeast that in some circumstances may cause oral or oropharyngeal infections. This investigation aimed to study the prevalence of Candida spp. and to analyze the ABC genotypes of 76 clinical isolates of C. albicans obtained from the oral cavity of kidney transplant patients from two distinct geographic regions of Brazil. Methods We typed 48 strains with ABC genotyping and Microsatelitte using primer M13 and tested three virulence factors in vitro: phospholipase activity, morphogenesis and the ability to evade from polymorphonuclear neutrophils phagocytosis. Results C. albicans was the most prevalent species (86.4%), followed by C. tropicalis (4.5%). C. albicans genotype A was the most prevalent (58 isolates; 76.4%), followed by genotype C (15 isolates; 19.7%) and genotype B (3 isolates; 3.9%). When Microsatellite technique with primer M13 was applied, 80% of the isolates from the South were placed within the same cluster. The majority of Genotype C strains were grouped together within two different clusters. Genotype C was considered more resistant to PMNs attack than genotypes A and B. Strains isolated from the South of Brazil showed also better ability to combat PMNs phagocytosis. Conclusions We found a high rate of C. albicans genotype C strains isolated from the oral cavity of this group of patients. This study characterized oral C. albicans strains isolated from kidney transplant recipients and will contribute to a better understanding of the pathogenesis of oral candidiasis. PMID:24628850

  4. Clonal Strain Persistence of Candida albicans Isolates from Chronic Mucocutaneous Candidiasis Patients

    PubMed Central

    Moorhouse, Alexander J.; Rennison, Claire; Raza, Muhammad; Lilic, Desa; Gow, Neil A. R.

    2016-01-01

    Chronic mucocutaneous candidiasis (CMC) is a primary immunodeficiency disorder characterised by susceptibility to chronic Candida and fungal dermatophyte infections of the skin, nails and mucous membranes. Molecular epidemiology studies of CMC infection are limited in number and scope and it is not clear whether single or multiple strains inducing CMC persist stably or are exchanged and replaced. We subjected 42 C. albicans individual single colony isolates from 6 unrelated CMC patients to multilocus sequence typing (MLST). Multiple colonies were typed from swabs taken from multiple body sites across multiple time points over a 17-month period. Among isolates from each individual patient, our data show clonal and persistent diploid sequence types (DSTs) that were stable over time, identical between multiple infection sites and exhibit azole resistant phenotypes. No shared origin or common source of infection was identified among isolates from these patients. Additionally, we performed C. albicans MLST SNP genotype frequency analysis to identify signatures of past loss of heterozygosity (LOH) events among persistent and azole resistant isolates retrieved from patients with autoimmune disorders including CMC. PMID:26849050

  5. Decolorization of textile dye by Candida albicans isolated from industrial effluents.

    PubMed

    Vitor, Vivian; Corso, Carlos Renato

    2008-11-01

    The aim of the present work was to observe microbial decolorization and biodegradation of the Direct Violet 51 azo dye by Candida albicans isolated from industrial effluents and study the metabolites formed after degradation. C. albicans was used in the removal of the dye in order to further biosorption and biodegradation at different pH values in aqueous solutions. A comparative study of biodegradation analysis was carried out using UV-vis and FTIR spectroscopy, which revealed significant changes in peak positions when compared to the dye spectrum. Theses changes in dye structure appeared after 72 h at pH 2.50; after 240 h at pH 4.50; and after 280 h at pH 6.50, indicating the different by-products formed during the biodegradation process. Hence, the yeast C. albicans was able to remove the color substance, demonstrating a potential enzymatic capacity to modify the chemical structure of pigments found in industrial effluents.

  6. In vitro synergy of pseudolaric acid B and fluconazole against clinical isolates of Candida albicans.

    PubMed

    Guo, Na; Ling, Guanghui; Liang, Xiaoying; Jin, Jing; Fan, Junwen; Qiu, Jiazhang; Song, Yu; Huang, Ning; Wu, Xiuping; Wang, Xuelin; Deng, Xuming; Deng, Xuliang; Yu, Lu

    2011-09-01

    Candida albicans is the most common fungal pathogen in humans. The emergence of resistance to azole antifungals has raised the issue of using such antifungals in combination to optimise therapeutic outcome. The objective of this study was to evaluate in vitro synergy of pseudolaric acid B (PAB) and fluconazole (FLC) against clinical isolates of C. albicans. The in vitro antifungal activity of PAB, a diterpene acid from Pseudolarix kaempferi Gordon, was evaluated alone and in combination with FLC against 22 FLC-resistant (FLC-R) and 12 FLC-susceptible (FLC-S) C. albicans using the chequerboard microdilution method and time-killing test assays. Synergism was observed in all 22 (100%) FLC-R strains tested as determined by both fractional inhibitory concentration index (FICI) with values ranging from 0.02 to 0.13 and bliss independence (BI) models. Synergism was observed in two of 12 (17%) FLC-S strains as determined by FICI model with values ranging from 0.25 to 0.5 and in three of 12 (18%) FLC-S strains as determined by BI model. For FLC-R strains, the drug concentrations of FLC and PAB, where synergistic interactions were found, ranged from 0.06 to 4 μg ml(-1) and 0.5 to 4 μg ml(-1) respectively. For FLC-S strains, the drug concentrations of FLC and PAB were 1-8 μg ml(-1) and 0.5-4 μg ml(-1) respectively. The BI model gave results consistent with FICI, but no antagonistic activity was observed in any of the strains tested. These interactions between PAB and FLC were confirmed using the time-killing test for the selected strains. Fluconazole and PAB exhibited a good synergism against azole-R isolates of C. albicans. © 2010 Blackwell Verlag GmbH.

  7. Effect of edible sesame oil on growth of clinical isolates of Candida albicans.

    PubMed

    Ogawa, Toshiko; Nishio, Junko; Okada, Shinobu

    2014-07-01

    Elderly individuals are at increased risk of oral thrush (oral candidiasis) due to decreased saliva secretion. Due to their antimicrobial properties, edible oils can be effective natural agents for oral care. The objective of the present study was to compare the effects of sesame oil, which is widely used for cooking in Asian countries, and two other edible oils on the growth of both mycelial and yeast forms of five clinical isolates of Candida albicans, a causative microorganism of oral thrush. We assessed the effect of each oil in concentrations of 0.078%, 0.156%, and 0.313% on growth of the mycelial forms of the clinical isolates over 24 hr using the crystal violet method. We also evaluated the effect of each oil on growth of the yeast forms by counting the number of viable yeast cells after culturing in the oils for 24 hr. Sesame oil inhibited the growth of both mycelial and yeast forms. Safflower and olive oil also inhibited the growth of both forms of C. albicans but to a lesser extent than sesame oil. The ability to inhibit the growth of the mycelial form correlated with sesame oil concentration. Roasting influenced growth inhibition ability and high-roasted sesame oil most effectively inhibited the yeast form. The growth inhibitory effect differed among the five isolates. We hypothesize that the sesamin and fatty acid components of sesame oil are involved in its antifungal activity. © The Author(s) 2013.

  8. Susceptibilities of Candida albicans mouth isolates to antifungal agents, essentials oils and mouth rinses.

    PubMed

    Carvalhinho, Sara; Costa, Ana Margarida; Coelho, Ana Cláudia; Martins, Eugénio; Sampaio, Ana

    2012-07-01

    Forty Candida albicans strains isolated from patient's mouth with fixed orthodontic appliances were analyzed to their susceptibilities to antifungal agents, mouth rinses and essential oils. Susceptibility to fluconazole, econazole, miconazole and ketoconazole, amphotericin B and nystatin was assessed by the disk diffusion (DD) method based on the Clinical and Laboratory Standards Institute M44-A protocol, and by Etest (fluconazole and amphotericin B). The susceptibilities to mouth rinses and essential oils were also determined by the DD technique. All isolates tested were susceptible (S) to amphotericin B, nystatin and fluconazole. The overall concordance between the DD and the Etest was 100% for amphotericin and fluconazole. One isolate was resistant to econazole (2.5%) and the other to ketoconazole (2.5%). Econazole and ketoconazole had the highest percentages of susceptible dose dependent (SDD), 55 and 95%, respectively. Regarding to the susceptibility isolates profile, seven phenotypes were detected, and the 3 more represented (90% of the isolates) of them were SDD to one, two or three azoles. The study of mouth rinses showed a high variability of efficacy against C. albicans. The results showed that the isolates susceptibility to essential oils differed (P < 0.05). The profile activity was: cinnamon > laurel > mint > eucalyptus > rosemary > lemon > myrrh > tangerine. The main finding was that the susceptibility to cinnamon and laurel varied among the three more representative antifungal phenotypes (P < 0.05). The susceptibility of econazole-SDD isolates to cinnamon and lemon was higher than those of the econazole-S yeasts (P < 0.05). In contrast, econazole-SDD isolates were less affected by laurel than econazole-S counterparts (P < 0.05).

  9. 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

  10. Overexpression of MDR-1 and CDR-2 genes in fluconazole resistance of Candida albicans isolated from patients with vulvovaginal candidiasis.

    PubMed

    Khosravi Rad, K; Falahati, M; Roudbary, M; Farahyar, S; Nami, S

    2016-12-01

    Candida albicans (C. albicans) is an opportunistic fungus that can colonize women's mucosal epithelial cell surfaces, causing vulvovaginitis in specific circumstances. The major genes contributing to drug resistance in C. albicans are the candida drug resistance (CDR) and multi drug resistance (MDR) genes. The purpose of this study was to evaluate the CDR-2 and MDR-1 gene expression patterns in C. albicans strains isolated from patients with recurrent vulvovaginal candidiasis. In this study, 40 isolates of fluconazole-resistant C. albicans were cultured on Sabouraud dextrose agar. These isolates were collected from women with vulvovaginitis who were referred to a clinic in Tehran, Iran, and transferred to a mycology laboratory. Then, RNA was extracted from the isolates using phenol-chloroform and glass beads, and the complementary DNA (cDNA) was synthetized. To detect the semi-quantitative expression of CDR-2 and MDR-1 genes, the reverse transcriptase-PCR (RT-PCR) technique was performed using specific primers. Our findings indicated that of the 40 C. albicans isolates, 35 (87.5%) strains were positive for mRNA of the CDR-2 gene, 32 (80%) strains expressed mRNA of the MDR-1 gene, and 30 (75%) strains were confirmed to express mRNA of both the CDR-2 and MDR-1 genes simultaneously using the RT-PCR assay. According to the obtained results, the expression rates of CDR-2 and MDR-1 genes were high in fluconazole-resistant C. albicans isolates, which can cause treatments to fail and result in chronic infections. Inhibiting these important genes using novel or natural agents can help with the treatment of chronic and recurrent vaginitis.

  11. ALS1 and ALS3 gene expression and biofilm formation in Candida albicans isolated from vulvovaginal candidiasis.

    PubMed

    Roudbarmohammadi, Shahla; Roudbary, Maryam; Bakhshi, Bita; Katiraee, Farzad; Mohammadi, Rasoul; Falahati, Mehraban

    2016-01-01

    A cluster of genes are involved in the pathogenesis and adhesion of Candida albicans to mucosa and epithelial cells in the vagina, the important of which is agglutinin-like sequence (ALS) genes. As well as vaginitis is a significant health problem among women, the antifungal resistance of Candida species is continually increasing. This cross-sectional study investigates the expression of ALS1 and ALS3 genes and biofilm formation in C. albicans isolate isolated from vaginitis. Fifty-three recognized isolates of C. albicans were collected from women with recurrent vulvovaginal candidiasis in Iran, cultured on sabouraud dextrose agar, and then examined for gene expression. Total messenger RNA (mRNA) extracted from C. albicans isolates and complementary DNA synthesized using reverse transcriptase enzyme. Reverse transcription-polymerase chain reaction (RT-PCR) using specific primer was used to evaluate the expression of ALS1 and ALS3 through housekeeping (ACT1) genes. 3-(4,5-dimethyl-2-thiazyl)-2,5-diphenyl-2H-tetrazolium bromide assay was performed to assess adherence capacity and biofilm formation in the isolated. Forty isolates (75.8%) expressed ALS1 and 41 isolates (77.7%) expressed ALS3 gene. Moreover, 39 isolates (74%) were positive for both ALS1 and ALS3 mRNA by the RT-PCR. Adherence capability in isolates with ALS1 or ALS3 genes expression was greater than the control group (with any gene expression), besides, it was significantly for the most in the isolates that expressed both ALS1 and ALS3 genes simultaneously. The results attained indicated that there is an association between the expression of ALS1 and ALS3 genes and fluconazole resistance in C. albicans. A considerable percent of the isolates expressing the ALS1 and ALS3 genes may have contributed to their adherence to vagina and biofilm formation.

  12. [Comparative study of the Candida albicans genotypes isolated from immunocompromised patients and health carriers].

    PubMed

    Carnovale, S; Elias Costa, M R; Relloso, S; Negroni, R; Negroni, M B; Iovannitti, C

    2001-01-01

    The aim of this study is to compare Candida albicans strain genotype isolates from oral cavity of immunocompromised patients due to different immunologic impairments with apparently normal carriers. Four populations were studied: 1) HIV positive hospitalized patients, 2) HIV negative immunocompromised patients (leukemia, lymphoma, organ transplant recipients), 3) drug addicts prior to AIDS pandemia in Argentina, 4) apparently normal carriers. DNA extracted was digested with the enzyme Eco RI, electrophoresed, transferred to nitrocellulose membrane and hybridized with the 27A probe labelled with 32P. The comparison between the profiles obtained permitted the differentiation of 16 genotypes. The distribution of the strains led to the conclusion that: a) all the isolated strains from AIDS patients were closely related and distributed in only three genotypes (1, 3, 11); b) a major genetic relationship between the isolates from AIDS patients and HIV negative immunocompromised patients was observed; c) strains from carriers showed a minor genetic similarity with those obtained from AIDS patients; d) characteristic profiles belonging to any of the studied groups were not found; e) significant genomic changes have not been observed during the last twenty years.

  13. Expression of the CDR1 efflux pump in clinical Candida albicans isolates is controlled by a negative regulatory element

    SciTech Connect

    Gaur, Naseem Akhtar; Manoharlal, Raman; Saini, Preeti; Prasad, Tulika; Mukhopadhyay, Gauranga; Hoefer, Milan; Morschhaeuser, Joachim; Prasad, Rajendra . E-mail: rp47@hotmail.com

    2005-06-24

    Resistance to azole antifungal drugs in clinical isolates of the human fungal pathogen Candida albicans is often caused by constitutive overexpression of the CDR1 gene, which encodes a multidrug efflux pump of the ABC transporter superfamily. To understand the relevance of a recently identified negative regulatory element (NRE) in the CDR1 promoter for the control of CDR1 expression in the clinical scenario, we investigated the effect of mutation or deletion of the NRE on CDR1 expression in two matched pairs of azole-sensitive and resistant clinical isolates of C. albicans. Expression of GFP or lacZ reporter genes from the wild type CDR1 promoter was much higher in the azole-resistant C. albicans isolates than in the azole-susceptible isolates, reflecting the known differences in CDR1 expression in these strains. Deletion or mutation of the NRE resulted in enhanced reporter gene expression in azole-sensitive strains, but did not further increase the already high CDR1 promoter activity in the azole-resistant strains. In agreement with these findings, electrophoretic mobility shift assays showed a reduced binding to the NRE of nuclear extracts from the resistant C. albicans isolates as compared with extracts from the sensitive isolates. These results demonstrate that the NRE is involved in maintaining CDR1 expression at basal levels and that this repression is overcome in azole-resistant clinical C. albicans isolates, resulting in constitutive CDR1 overexpression and concomitant drug resistance.

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

    PubMed Central

    Shirazi, F; Kontoyiannis, DP

    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. PMID:26065323

  15. 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.

  16. Increased expression of Candida albicans secretory proteinase, a putative virulence factor, in isolates from human immunodeficiency virus-positive patients.

    PubMed Central

    Ollert, M W; Wende, C; Görlich, M; McMullan-Vogel, C G; Borg-von Zepelin, M; Vogel, C W; Korting, H C

    1995-01-01

    The increased prevalence and the severity of oropharyngeal candidiasis in human immunodeficiency virus (HIV)-positive patients are attributed exclusively to the virus-induced immune deficiency of the host. The present study was aimed at answering the question of whether Candida albicans secretory proteinase, a putative virulence factor of the opportunistic C. albicans yeast, has any potential influence on the clinical manifestation of oropharyngeal candidiasis in HIV-positive patients. We measured the secretory proteinase activities of clinical C. albicans isolates from the oropharynges of either HIV-positive individuals (n = 100) or a control group (n = 122). The mean secretory proteinase activity of C. albicans isolates from the HIV-positive group (4,255 +/- 2,372 U/liter) was significantly higher compared with that of isolates from the control group (2,324 +/- 1,487 U/liter) (P < 0.05). The higher level of secretory proteinase activity in the culture supernatants of individual C. albicans isolates correlated with the increased level of proteinase expression on the cell surface, as revealed by cytofluorometry, and with higher levels of secretion of the immunodetectable protein, as shown by Western blotting (immunoblotting). Proteinase activity within the population of C. albicans isolates from HIV-positive individuals was independent of the patient's clinical disease stage and the CD4+/CD8+ cell numbers. Furthermore, no correlation of the proteinase activities with the C. albicans serotype was found, although C. albicans serotype B was significantly more frequent in the HIV-positive group (40%) compared with that in the control group (12%). However, a positive correlation of proteinase activity to antifungal susceptibility was evident.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8567880

  17. Phenotype and genotype of Candida albicans strains isolated from pregnant women with recurrent vaginitis.

    PubMed

    Maffei, C M; Paula, C R; Mazzocato, T S; Franceschini, S

    1997-01-01

    Fourteen out of 80 pregnant women receiving prenatal care presented signs and symptoms of recurrent vaginal candidiasis. Candida albicans strains were isolated from 12 patients (85.7%), and these were submitted to morphotyping (morphological characteristics of the colony), antifungal typing (pattern of sensitivity to amphotericin B, 5-fluorcytosine, myconazole, ketoconazole and fluconazole) and genotyping (electrophoretic migration of DNA fragments digested with EcoRI and HinfI). Alteration of morphotype and antifungal type was observed in 50% of the patients, but the genotype of the strains isolated from the same patients at different times was identical in all subjects. The predominant morphotypes presented continuous fringes and the basic changes observed among antifungal types was the emergence of strains resistant to myconazole, which was the drug used for the treatment of the first episode of vaginitis. We conclude that recurrent vaginal candidasis is caused by the persistence of a single yeast genotype that undergoes morphological and behavioral changes in the presence of antifungal agents due to the selective pressure to which it is submitted.

  18. Prevalence and exoenzyme secretion by Candida albicans isolates from oral and vaginal mucosas of HIV-infected women.

    PubMed

    Ribeiro, Mariceli Araujo; Miranda, Angelica Espinosa; Gambale, Walderez; Paula, Claudete Rodrigues

    2004-04-01

    A cross-sectional study was performed to evaluate the prevalence and the aetiology of forms of mucosal fungal infections of HIV-negative and HIV-positive women. Candida albicans was the predominate specie isolated from both groups of patients, with remarkable proportion of isolation from symptomatic women. All 239 C. albicans isolates, regardless of their source, showed activity of proteinase and phospholipase. It was verified that isolates with particularly higher levels of exoenzymes production were significantly more common in HIV-positive patients. However, isolates obtained from the HIV-positive patients in use of HAART, with protease inhibitor, presented lower levels of these exoenzymes, similar to the levels observed in the isolates from HIV-negative patients.

  19. Accumulation of 3-Ketosteroids Induced by Itraconazole in Azole-Resistant Clinical Candida albicans Isolates

    PubMed Central

    Marichal, Patrick; Gorrens, Jos; Laurijssens, Leen; Vermuyten, Karen; Van Hove, Carl; Le Jeune, Ludo; Verhasselt, Peter; Sanglard, Dominique; Borgers, Marcel; Ramaekers, Frans C. S.; Odds, Frank; Vanden Bossche, Hugo

    1999-01-01

    The effects of itraconazole on ergosterol biosynthesis were investigated in a series of 16 matched clinical Candida albicans isolates which had been previously analyzed for mechanisms of resistance to azoles (D. Sanglard, K. Kuchler, F. Ischer, J. L. Pagani, M. Monod, and J. Bille, Antimicrob. Agents Chemother., 39:2378–2386, 1995). Under control conditions, all isolates contained ergosterol as the predominant sterol, except two strains (C48 and C56). In isolates C48 and C56, both less susceptible to azoles than their parent, C43, substantial concentrations (20 to 30%) of 14α-methyl-ergosta-8,24(28)-diene-3β,6α-diol (3,6-diol) were found. Itraconazole treatment of C43 resulted in a dose-dependent inhibition of ergosterol biosynthesis (50% inhibitory concentration, 2 nM) and accumulation of 3,6-diol (up to 60% of the total sterols) together with eburicol, lanosterol, obtusifoliol, 14α-methyl-ergosta-5,7,22,24(28)-tetraene-3βol, and 14α-methyl-fecosterol. In strains C48 and C56, no further increase of 3,6-diol was observed after exposure to itraconazole. Ergosterol synthesis was less sensitive to itraconazole inhibition, as was expected for these azole-resistant isolates which overexpress ATP-binding cassette transporter genes CDR1 and CDR2. In addition to 3,6-diol, substantial amounts of obtusifolione were found after exposure to itraconazole. This toxic 3-ketosteroid was demonstrated previously to accumulate after itraconazole treatment in Cryptococcus neoformans and Histoplasma capsulatum but has not been reported in Candida isolates. Accumulation of obtusifolione correlated with nearly complete growth inhibition in these azole-resistant strains compared to that found in the susceptible parent strain, although the onset of growth inhibition only occurred at higher concentrations of itraconazole. ERG25 and ERG26 are the only genes assigned to the 4-demethylation process, of which the 3-ketoreductase is part. To verify whether mutations in these ERG25 genes

  20. Phospholipase activity of Candida albicans isolates from patients with denture stomatitis: the influence of chlorhexidine gluconate on phospholipase production.

    PubMed

    Kadir, Tanju; Gümrü, Birsay; Uygun-Can, Banu

    2007-07-01

    The extracellular phospholipases of Candida albicans are considered to play a significant role in the pathogenesis of human infections. Therefore 23 clinical oral isolates of C. albicans from patients with denture stomatitis and 22 commensal oral isolates obtained from the palatal mucosa of healthy subjects were assayed for phospholipase activity. It is generally accepted that chlorhexidine gluconate is an appropriate adjunct or an alternative to antimycotic therapy in the management of oral candidiasis. However, the intraoral concentrations of this antiseptic fluctuate considerably due to the dynamics of the oral cavity. So the second main objective of this study was to investigate the effect of brief exposure (30 min) to two sub-therapeutic concentrations (0.002% and 0.0012%) of chlorhexidine gluconate on the value of phospholipase production (Pz) of C. albicans. An in vitro phospholipase production was done by plate assay method using an egg yolk-agar medium. No significant differences were found in the number of C. albicans isolates producing phospholipase between two groups. However, the mean value of Pz produced by the isolates from patients with denture stomatitis was significantly (p<0.05) higher than the commensals. Exposure of the isolates to 0.002% and 0.0012% chlorhexidine led to a significant (p<0.001 and p<0.01, respectively) reduction in the amount of phospholipase. The results of this study imply that sub-therapeutic levels of chlorhexidine may modulate candidal phospholipase activity, thereby suppressing pathogenicity of C. albicans.

  1. [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%).

  2. Cluster of oral atypical Candida albicans isolates in a group of human immunodeficiency virus-positive drug users.

    PubMed Central

    Boerlin, P; Boerlin-Petzold, F; Durussel, C; Addo, M; Pagani, J L; Chave, J P; Bille, J

    1995-01-01

    Twenty-one chlamydospore-forming and germ tube-positive Candida albicans clinical isolates from 15 human immunodeficiency virus (HIV)-positive and 3 HIV-negative patients were examined by two different genetic methods. Multilocus enzyme electrophoresis and hybridization with the C. albicans-specific Ca3 probe showed that such isolates can be split into two genetically distinct groups that can be clearly distinguished. One group mainly contained strains with atypical sugar assimilation patterns and could be distinguished from the other group by the absence of intracellular beta-glucosidase activity. All 13 strains belonging to this group were isolated from the oral cavities of asymptomatic HIV-positive drug users and may be less pathogenic than the eight strains from the other group isolated either from HIV-positive patients with oropharyngeal candidiasis or from HIV-negative patients with invasive candidiasis. PMID:7615716

  3. Comparison of multilocus sequence typing and Ca3 fingerprinting for molecular subtyping epidemiologically-related clinical isolates of Candida albicans.

    PubMed

    Chowdhary, Anuradha; Lee-Yang, Wendy; Lasker, Brent A; Brandt, Mary E; Warnock, David W; Arthington-Skaggs, Beth A

    2006-08-01

    Southern hybridization with the complex probe Ca3 is a well established tool for molecular subtyping of Candida albicans. Multilocus sequence typing (MLST) is a DNA sequence-based subtyping method recently applied to C. albicans and shown to have a high degree of intraspecies discriminatory power. However, its utility for studying the molecular epidemiology of sequential isolates from recurrent disease has not been established. We compared Ca3 Southern hybridization and MLST using seven housekeeping genes (CaAAT1a, CaACC1, CaADP1, CaPMI, CaSYA1, CaVPS13, CaZWF1b) for their ability to discriminate among 37 C. albicans isolates from recurrent cases of oropharyngeal candidiasis (OPC) in ten HIV-positive patients from India and the US. Among the 37 isolates, MLST identified 23 distinct genotypes (index of diversity = 97%); Ca3 Southern hybridization identified 21 distinct genotypes (index of diversity = 95%). Both methods clustered isolates into seven genetically-related groups and, with one exception, isolates that were indistinguishable by MLST were indistinguishable or highly related by Ca3 Southern hybridization. These results demonstrate that MLST performs equally well or better compared to Ca3 Southern hybridization for defining genetic-relatedness of sequential C. albicans isolates from recurrent cases of OPC in HIV-positive patients.

  4. Susceptibility profile of vaginal isolates of Candida albicans prior to and following fluconazole introduction - impact of two decades.

    PubMed

    Bulik, C C; Sobel, J D; Nailor, M D

    2011-01-01

    Current treatment options for vulvovaginal candidiasis due to Candida albicans include over-the-counter and prescription antifungal agents. Fluconazole has been used extensively with an unknown impact on susceptibility. To investigate antifungal susceptibility trends in clinical vaginal isolates of C. albicans from 1986 to 2008, microdilution susceptibility was performed on randomly selected single isolates. Minimum inhibitory concentrations (MICs) were determined for: fluconazole, clotrimazole, miconazole, ketoconazole, itraconazole, voriconazole, flucytosine and amphotericin B. The MIC(90) for each drug was then calculated for the time periods: 1986-1989, 1992-1996 and 2005-2007. A total of 250 C. albicans vaginal isolates were included. The MIC(90) (mcg ml(-1) ) for fluconazole was 0.25, 0.5 and 0.5 mcg ml(-1) for each grouping, respectively. The corresponding MIC(90) for flucytosine was 1, 2 and 8 mcg ml(-1) , respectively. The MIC(90) for the remaining agents remained unchanged across time periods mentioned. Of note, the percentage of isolates with MIC ≥1 and ≥2 mcg ml(-1) for fluconazole increased from 3% to 9% over the study period. Although the C. albicans MIC(90) to fluconazole in vaginal isolates has not shown a clinically significant increase since 1986, there is an increasing number of isolates with elevated MICs. The implications of this increase are unknown, but given the achievable vaginal concentrations of fluconazole, reduced susceptibility may have clinical relevance.

  5. Oral Candida albicans isolates from nonhospitalized normal carriers, immunocompetent hospitalized patients, and immunocompromised patients with or without acquired immunodeficiency syndrome.

    PubMed Central

    Brawner, D L; Cutler, J E

    1989-01-01

    A total of 128 human oral isolates of Candida albicans were collected from asymptomatic healthy carriers (64 isolates); asymptomatic, nonimmunosuppressed, hospitalized patients (25 isolates); immunosuppressed transplant patients (19 isolates); and human immunodeficiency virus-infected patients with symptoms of acquired immunodeficiency syndrome and oral candidiasis (20 isolates). Isolates were serotyped as A or B and tested for reactivity with an agglutinating immunoglobulin M monoclonal antibody (H9). Immunocompetent individuals colonized by oral C. albicans were almost equally likely to carry serotype A as serotype B cells, while immunocompromised individuals were at least twice as likely to be infected by serotype B than serotype A strains. The reactivity of isolates with H9 antibody followed a similar but more distinctive pattern. Approximately half of the strains from immunocompetent individuals reacted strongly with H9, and the remainder reacted weakly. However, up to 75% of the isolates from immunocompromised patients reacted weakly with H9, while the remainder reacted strongly. A correlation between H9 reactivity and the serotypes of these isolates existed (P = 0.16). The correlation between H9 reactivity and immune status was even stronger (P = 0.025). The monoclonal antibody activities described above were determined by agglutination tests during defined phases of C. albicans growth. Expression of antigen at various times during growth of several isolates was confirmed at the cellular level by analysis using fluorescence-activated cell sorting. Despite the correlation between serotype A and H9 reactivity, H9 antigen was not identical to the serotype A antigen because four serotype A strains reacted only weakly with H9 antibody, and one strain reacted strongly with H9 but was serotype B. These data indicate that oral strains of C. albicans from immunocompetent individuals differ as a group from C. albicans isolated from those who are immunosuppressed. PMID

  6. Mutations in transcription factor Mrr2p contribute to fluconazole resistance in clinical isolates of Candida albicans.

    PubMed

    Wang, Ying; Liu, Jin-Yan; Shi, Ce; Li, Wen-Jing; Zhao, Yue; Yan, Lan; Xiang, Ming-Jie

    2015-11-01

    The Candida albicans zinc cluster proteins are a family of transcription factors (TFs) that play essential roles in the development of antifungal drug resistance. Gain-of-function mutations in several TFs, such as Tac1p, Mrr1p and Upc2p, have been previously well documented in azole-resistant clinical C. albicans isolates. Mrr2p (multidrug resistance regulator 2) is a novel TF controlling expression of the ABC transporter gene CDR1 and mediating fluconazole resistance. In this study, the relationship between naturally occurring mutations in MRR2 and fluconazole resistance in clinical C. albicans isolates was investigated. Among a group of 20 fluconazole-resistant clinical C. albicans and 10 fluconazole-susceptible C. albicans, 12 fluconazole-resistant isolates overexpressed CDR1 by at least two-fold compared with the fluconazole-susceptible isolates. Of these 12 resistant isolates, three (C7, C9, C15) contained 11 identical missense mutations, 6 of which occurred only in the azole-resistant isolates. The contribution of these mutations to CDR1 overexpression and therefore to fluconazole resistance was further verified by generating recombinant strains containing the mutated MRR2 gene. The mutated MRR2 alleles from isolate C9 contributed to an almost six-fold increase in CDR1 expression and an eight-fold increase in fluconazole resistance; the missense mutations S466L and T470N resulted in an increase in CDR1 expression of more than two-fold and a four-fold increase in fluconazole resistance. In contrast, the other four missense mutations conferred only two- to four-fold increases in fluconazole resistance, with no significant increase in CDR1 expression. These findings provide some insight into the mechanism by which MRR2 regulates C. albicans multidrug resistance.

  7. In vitro activity of xanthorrhizol isolated from the rhizome of Javanese turmeric (Curcuma xanthorrhiza Roxb.) against Candida albicans biofilms.

    PubMed

    Rukayadi, Yaya; Hwang, Jae-Kwan

    2013-07-01

    The purpose of this study was to investigate the activity of xanthorrhizol isolated from Curcuma xanthorrhiza Roxb. on Candida albicans biofilms at adherent, intermediate, and mature phase of growth. C. albicans biofilms were formed in flat-bottom 96-well microtiter plates. The biofilms of C. albicans at different phases of development were exposed to xanthorrhizol at different concentrations (0.5 µg/mL-256 µg/mL) for 24 h. The metabolic activity of cells within the biofilms was quantified using the XTT reduction assay. Sessile minimum inhibitory concentrations (SMICs) were determined at 50% and 80% reduction in the biofilm OD₄₉₀ compared to the control wells. The SMIC₅₀ and SMIC₈₀ of xanthorrhizol against 18 C. albicans biofilms were 4--16 µg/mL and 8--32 µg/mL, respectively. The results demonstrated that the activity of xanthorrhizol in reducing C. albicans biofilms OD₄₉₀ was dependent on the concentration and the phase of growth of biofilm. Xanthorrhizol at concentration of 8 µg/mL completely reduced in biofilm referring to XTT-colorimetric readings at adherent phase, whereas 32 µg/mL of xanthorrhizol reduced 87.95% and 67.48 % of biofilm referring to XTT-colorimetric readings at intermediate and mature phases, respectively. Xanthorrhizol displayed potent activity against C. albicans biofilms in vitro and therefore might have potential therapeutic implication for biofilm-associated candidal infections.

  8. Absence of Photoreactivating Enzyme in Candida albicans, Candida stellatoidea, and Candida tropicalis

    PubMed Central

    Miller, Glendon R.; Sarachek, Alvin

    1974-01-01

    In vitro assays demonstrate photoreactivating enzyme activity in extracts of Candida pseudotropicalis but not in extracts of Candida albicans, Candida stellatoidea, or Candida tropicalis. PMID:4604052

  9. Candida albicans bloodstream isolates in a German university hospital are genetically heterogenous and susceptible to commonly used antifungals.

    PubMed

    Huyke, Johanna; Martin, Ronny; Walther, Grit; Weber, Michael; Kaerger, Kerstin; Bougnoux, Marie-Elisabeth; Elias, Johannes; Kurzai, Oliver

    2015-10-01

    From an eight-year-span, 99 Candida bloodstream isolates were collected at the University Hospital Wuerzburg, Germany. In this study, all strains were analyzed using molecular and phenotypic typing methods. Confirmatory species identification revealed three isolates that were initially diagnosed as C. albicans to be actually C. dubliniensis. Two isolates contained a mixed culture of C. albicans and C. glabrata, in one of the specimens both species could be separated while it was not possible to recover C. albicans in the other sample. The remaining 95 C. albicans isolates were profiled by multilocus sequence typing (MLST). Phylogenetic analyses showed a highly heterogenous collection of strains, associated with many different clades and constituting a set of new diploid sequence types (DST). For all strains with identical DST, patient data were reviewed for potential nosocomial transmission. In addition, all isolates were tested for their susceptibility to amphotericin B, caspofungin, fluconazole, itraconazole, posaconazole and voriconazole. No clinically relevant resistance could be detected. Furthermore, these data underline that correlation between minimal inhibitory concentrations for caspofungin and anidulafungin is low.

  10. Comparison between E-test and CLSI broth microdilution method for antifungal susceptibility testing of Candida albicans oral isolates.

    PubMed

    Koga-Ito, Cristiane Yumi; Lyon, Juliana Pereira; Resende, Maria Aparecida de

    2008-01-01

    Thirty Candida albicans isolated from oral candidosis patients and 30 C. albicans isolated from control individuals were studied. In vitro susceptibility tests were performed for amphotericin B, fluconazole, 5-flucytosine and itraconazole through the Clinical and Laboratorial Standards Institute (CLSI) reference method and E test system. The results obtained were analyzed and compared. MIC values were similar for the strains isolated from oral candidosis patients and control individuals. The agreement rate for the two methods was 66.67% for amphotericin B, 53.33% for fluconazole, 65% for flucytosine and 45% for itraconazole. According to our data, E test method could be an alternative to trial routine susceptibility testing due to its simplicity. However, it can not be considered a substitute for the CLSI reference method.

  11. Mechanisms of resistance to fluconazole in Candida albicans clinical isolates from Iranian HIV-infected patients with oropharyngeal candidiasis.

    PubMed

    Salari, S; Khosravi, A R; Mousavi, S A A; Nikbakht-Brojeni, G H

    2016-03-01

    The opportunistic pathogen Candida albicans is the major agent of oropharyngeal candidiasis (OPC) in HIV/AIDS patients. The increased use of fluconazole can lead to the emergence of azole-resistant strains and treatment failures in PLWH (people living with HIV) receiving long-term therapy for OPC. The purpose of this study was to evaluate CDR1, CDR2, MDR1, and ERG11 gene expression in C. albicans clinically isolated from HIV-infected patients in Iran. In this study, we evaluated the molecular mechanisms of azole resistance in 20 fluconazole-resistant C. albicans isolates obtained from Iranian HIV-infected patients with oropharyngeal candidiasis by Real-Time polymerase chain reaction. The overexpression of drug efflux pump CDR1 gene was found to be the major resistance mechanism observed in these isolates. The overexpression of the CDR1 gene correlated strongly with increasing resistance to fluconazole (P<0.05). Additionally, an increased level of mRNA in ERG11 was not observed in any of the tested isolates. Our findings suggested that the CDR1 gene expression to fluconazole resistance in C. albicans is greater than other known genes. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  12. Therapeutic efficacy of posaconazole against isolates of Candida albicans with different susceptibilities to fluconazole in a vaginal model.

    PubMed

    González, Gloria M; Robledo, Efrén; Saldívar, Donato; González, Gerardo; Bosques, Francisco; Garza, Elvira

    2007-05-01

    A battery of 34 vaginal isolates of Candida albicans was tested against posaconazole (POS) and fluconazole (FLU) to determine their in vitro susceptibilities and to obtain FLU-susceptible and FLU-resistant strains for the murine in vivo studies. FLU-resistant strains were chosen on the basis of their 48-h MICs. The 48-h geometric mean MICs for all isolates tested were 0.016 and 0.656 microg/ml for POS and FLU, respectively. The treatment regimens for the vaginal murine infection model were POS or FLU at 10 or 20 mg/kg of body weight/day and 20 mg/kg twice a day. All regimens with POS were effective in reducing fungal burden of both the fluconazole-susceptible and resistant isolates of C. albicans. All FLU regimens were effective against infection induced by the fluconazole-susceptible strain. While FLU at 10 mg/kg was ineffective against fungal burden of the resistant strain, treatment with FLU at 20 mg/kg once or twice a day was effective against this strain. Both POS and FLU at 20 mg/kg twice a day were able to clear C. albicans from vaginas of mice infected with the fluconazole-susceptible strain. POS displayed a more effective in vivo activity than FLU in the treatment of murine C. albicans vaginitis produced by isolates with different susceptibilities to FLU.

  13. Biotypes and randomly amplified polymorphic DNA (RAPD) profiles of subgingival Candida albicans isolates in HIV infection.

    PubMed

    Pizzo, Giuseppe; Giammanco, Giovanni M; Pecorella, Sonia; Campisi, Giuseppina; Mammina, Caterina; D'Angelo, Matteo

    2005-01-01

    A group of subgingival isolates of C. albicans recovered from Italian HIV-positive (HIV+) subjects were characterized both phenotypically and genotypically. Phenotyping of the isolates was carried out by a biotyping method based on the enzyme profiles, carbohydrate assimilation patterns and boric acid resistance of the yeasts. Genotyping was performed through randomly amplified polymorphic DNA (RAPD) analysis. Five biotypes were found among the 29 subgingival C. albicans strains examined. The predominant biotypes were A1R (55.17%), A1S (24.14%), and A2R (13.79%), while the biotypes A11R and A13R were represented by a single isolate each. RAPD profiles identified 15 genotypes among the 29 isolates. Almost every individual harboured his/her own specific isolate and in three out of the six subjects with multiple isolates (two to six each) more than one genotype (two to six) was found. The biotype distribution we found is consistent with previous reports on C. albicans isolates from other oral sources, whereas the resistance to boric acid was highly frequent in subgingival strains. RAPD analysis showed high genetic heterogeneity within subgingival isolates, also when isolates were phenotypically identical. These findings, obtained from HIV+ subjects living in Southern Italy, may be useful as baseline information on subgingival C. albicans colonization in the Mediterranean area.

  14. 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

  15. 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.

  16. Use of Fourier-Transform Infrared Spectroscopy for Typing of Candida albicans Strains Isolated in Intensive Care Units

    PubMed Central

    Sandt, C.; Sockalingum, G. D.; Aubert, D.; Lepan, H.; Lepouse, C.; Jaussaud, M.; Leon, A.; Pinon, J. M.; Manfait, M.; Toubas, D.

    2003-01-01

    Comparative studies of Candida albicans strains are essential for proving cross-infections in epidemiological investigations. Typing of C. albicans strains is mainly based on genotypic methods. Fourier-transform infrared (FTIR) spectroscopy is described in this study as a novel phenotypic approach to the typing of C. albicans. The first step in the approach was the standardization of sample preparation (culture conditions and sampling parameters) and acquisition and classification parameters (spectral acquisition, spectral window selection, classification algorithm, and heterogeneity threshold). The second step consisted of validating the established parameters with a set of 79 strains of C. albicans isolated over 4 months from nine patients hospitalized in two intensive care units. Strains were isolated from multiple anatomical sites with repeated sampling. FTIR spectroscopy results were compared to randomly amplified polymorphic DNA (RAPD) results; this analysis showed that the amplification patterns of strains isolated from a given patient were identical and that different patients had different profiles. FTIR spectroscopy data were analyzed by hierarchical clustering performed with the second-derivative spectra. This classification revealed nine groups, one per patient. Only one spectrum out of 79 was misclassified by the FTIR spectroscopy method. RAPD and FTIR spectroscopy results were in good agreement, showing that, when nosocomial candidiasis transmission is suspected and urgent information is needed, this technique may be useful as a quick identification tool to give solid clues before confirmation by a genotypic method. PMID:12624015

  17. White-opaque Switching in Different Mating Type-like Locus Gene Types of Clinical Candida albicans Isolates.

    PubMed

    Li, Hou-Min; Shimizu-Imanishi, Yumi; Tanaka, Reiko; Li, Ruo-Yu; Yaguchi, Takashi

    2016-11-20

    Candida albicans (C. albicans) can become a pathogen causing superficial as well as life-threatening systemic infections, especially in immunocompromised patients. Many phenotypic attributes contribute to its capacity to colonize human organs. In our study, 93 C. albicans isolates from patients of various candidiasis in a hospital of China were surveyed. We aimed to investigate the white-opaque (WO) switching competence, drug sensitivity, and virulence of mating type-like (MTL) a/α isolates. Internal transcribed spacer (ITS) gene and the MTL configuration were detected in all the isolates by reverse transcription-polymerase chain reaction. White/opaque phenotype and doubling time of cell growth were determined. The minimum inhibitory concentrations of antifungal agent were measured using broth microdilution method. Sixty-four isolates (69.6%) were classified to serotype A, 19 (20.6%) to serotype B, and 9 (9.8%) to serotype C. Moreover, phylogenetic analysis showed that these isolates were divided into four different subgroups of ITS genotypes. Most of our clinical isolates were MTL a/α type, while 6.8% remained MTL a or MTLα type. The frequency of opaque phenotype was 71.0% (66 isolates). Following the guidelines of Clinical and Laboratory Standards Institute M27-A3, all isolates were susceptible to caspofungin and a few (0.6-3.2%) of them showed resistance against amphotericin B, flucytosine, fluconazole, itraconazole, and voriconazole. From these analyses, there were comparatively more C. albicans strains classified into serotype B, and the frequency of opaque phase strains was significant in the clinical isolates from China. Genetic, phenotypic, or drug susceptibility patterns were not significantly different from previous studies. MTL a/α isolates could also undergo WO switching which facilitates their survival.

  18. White-opaque Switching in Different Mating Type-like Locus Gene Types of Clinical Candida albicans Isolates

    PubMed Central

    Li, Hou-Min; Shimizu-Imanishi, Yumi; Tanaka, Reiko; Li, Ruo-Yu; Yaguchi, Takashi

    2016-01-01

    Background: Candida albicans (C. albicans) can become a pathogen causing superficial as well as life-threatening systemic infections, especially in immunocompromised patients. Many phenotypic attributes contribute to its capacity to colonize human organs. In our study, 93 C. albicans isolates from patients of various candidiasis in a hospital of China were surveyed. We aimed to investigate the white-opaque (WO) switching competence, drug sensitivity, and virulence of mating type-like (MTL) a/α isolates. Methods: Internal transcribed spacer (ITS) gene and the MTL configuration were detected in all the isolates by reverse transcription-polymerase chain reaction. White/opaque phenotype and doubling time of cell growth were determined. The minimum inhibitory concentrations of antifungal agent were measured using broth microdilution method. Results: Sixty-four isolates (69.6%) were classified to serotype A, 19 (20.6%) to serotype B, and 9 (9.8%) to serotype C. Moreover, phylogenetic analysis showed that these isolates were divided into four different subgroups of ITS genotypes. Most of our clinical isolates were MTLa/α type, while 6.8% remained MTLa or MTLα type. The frequency of opaque phenotype was 71.0% (66 isolates). Following the guidelines of Clinical and Laboratory Standards Institute M27-A3, all isolates were susceptible to caspofungin and a few (0.6–3.2%) of them showed resistance against amphotericin B, flucytosine, fluconazole, itraconazole, and voriconazole. Conclusions: From these analyses, there were comparatively more C. albicans strains classified into serotype B, and the frequency of opaque phase strains was significant in the clinical isolates from China. Genetic, phenotypic, or drug susceptibility patterns were not significantly different from previous studies. MTLa/α isolates could also undergo WO switching which facilitates their survival. PMID:27824006

  19. Increased expression of virulence attributes in oral Candida albicans isolates from human immunodeficiency virus-positive individuals.

    PubMed

    Mane, Arati; Gaikwad, Shraddha; Bembalkar, Shilpa; Risbud, Arun

    2012-02-01

    Oral candidiasis caused by Candida albicans is recognized as one of the most frequent opportunistic infections in human immunodeficiency virus (HIV)-infected individuals. The overall severity and chronicity of oral candidiasis has been attributed exclusively to the HIV-induced immune deficiency of the affected individuals but not to the virulence factors of the pathogen, i.e. C. albicans. However, genotypic and phenotypic studies have suggested that HIV infection might be associated with preferential selection of C. albicans strains with altered virulence determinants, leading to colonization with Candida populations that are better able to cause disease in these immunologically compromised hosts. If this process of selection is indeed related to pathogenicity, it may be possible to measure alterations in different virulence factors produced by C. albicans in HIV-infected patients. To evaluate this hypothesis, the present work was undertaken to determine simultaneously the expression of five virulence factors in oral C. albicans isolates colonizing and infecting HIV-positive and -negative individuals. The significance of genotypes in the pathogenesis of oral candidiasis was also elucidated. Oral swabs were collected from 335 consecutive individuals (210 HIV-positive and 125 HIV-negative). Virulence factors and genotypes were determined for all the C. albicans strains isolated. The results showed significantly increased expression of proteinase, phospholipase and haemolytic activities, as well as a greater ability to adhere, in isolates from HIV-positive compared with HIV-negative individuals (P<0.05). However, no significant differences in virulence factor expression in isolates colonizing or infecting HIV-positive individuals were seen. Genotype A was the predominant type (71.3 %); however, a relationship could not be established between the genotypes and the virulence factors, or with clinical infection. These data support the concept of preferential C. albicans

  20. Effect of lectins on hepatic clearance and killing of Candida albicans by the isolated perfused mouse liver.

    PubMed Central

    Sawyer, R T; Garner, R E; Hudson, J A

    1992-01-01

    The isolated perfused mouse liver model was used to study the effects of various lectins on hepatic trapping and killing of Candida albicans. After mouse livers were washed with 20 to 30 ml of perfusion buffer, 10(6) C. albicans CFU were infused into the livers. At the time of recovery, 63% +/- 2% (mean +/- standard error of the mean) of the infused C. albicans CFU were recovered from the liver and 14% +/- 1% were recovered from the effluent for a total recovery of 77% +/- 2%. This indicated that 86% +/- 9% of the original inoculum was trapped by the liver and that 23% +/- 2% was killed within the liver. When included in both preperfusion and postperfusion buffers (0.2 mg of lectin per ml), Ulex europeaus lectin (binding specificity for fucose) decreased hepatic trapping of C. albicans by 37% and eluted trapped C. albicans from the liver only when included in postperfusion buffer. By comparison, treatment of C. albicans with U. europeaus lectin before infusion had no effect on the trapping or killing of yeast cells. When Lens culinaris lectin (binding specificity for mannose) was included in the perfusion buffers, hepatic killing of C. albicans increased by 16% with no significant effect on hepatic killing when yeast cells were treated with L. culinaris lectin before infusion. Forty to 55% of the infused C. albicans were killed when concanavalin A (binding specificities for mannose and glucose), Glycine max (binding specificity for N-acetylgalactosamine), or Arachis hypogea (binding specificity for galactose) lectin was included in the perfusion buffer or when yeast cells were treated with these lectins before their infusion. When C. albicans was treated with concanavalin A at a concentration of less than 0.02 mg/ml, hepatic killing of yeast cells was not significantly increased. The data suggest that a fucose-containing receptor on the surface of either sinusoidal endothelial cells or Kupffer cells is involved in the trapping of C. albicans by the perfused mouse

  1. Differential Proteinase Patterns among Candida albicans Strains Isolated from Root Canal and Lingual Dorsum: Possible Roles in Periapical Disease.

    PubMed

    Miranda, Tatiana Teixeira; Vianna, Cristina R; Rodrigues, Leonardo; Rosa, Carlos Augusto; Corrêa, Ary

    2015-06-01

    Proteinases play pivotal roles in Candida albicans infections. Although the yeast can colonize the pulpal environment, there is no information about the enzymatic profile of this organism. This in vitro study aimed to determine the proteolysis levels and to investigate differences in the expression of aspartyl proteinase genes (Sap 1, Sap 2, and Sap 4) among various root canal strains and clinical isolates from the lingual dorsum. The extracellular proteinase activity of 104 C. albicans samples isolated from the lingual dorsum and from necrotic root canals was measured with respect to bovine serum albumin degradation after 5 days of incubation at 37°C. We used reverse-transcription polymerase chain reaction, a highly sensitive method, to detect messenger RNA transcripts of aspartyl proteinase genes (Sap 1, Sap 2, and Sap 4). The C. albicans strain SC 5314 was used as a positive control for both experiments because it is recognized as being highly proteolytic. All tests were performed in triplicate. Regardless of the isolation site, all C. albicans strains produced an opaque precipitation halo around the colonies, indicating some proteinase activity. However, the production of proteinase on the plates was significantly greater (P < .05) by the endodontic samples. Sap 2 was the most commonly expressed gene in all samples. Among the root canal samples, the detection of Sap 1 transcripts was always associated with the expression of Sap 2 and Sap 4. Sap 4 gene expression was detected in all root canal samples. The simultaneous expression of the 3 investigated Sap genes (Sap 1, Sap 2, and Sap 4) was more common in strains isolated from the lingual dorsum (50%) than in those isolated from root canals (29.4%). The increased proteolytic activity as well as the distinct pattern of Sap expression observed among the root canal samples may suggest a pathogenic role for C. albicans in endodontic infections. Copyright © 2015 American Association of Endodontists. Published by

  2. 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.

  3. Hibiscus sabdariffa extract inhibits in vitro biofilm formation capacity of Candida albicans isolated from recurrent urinary tract infections

    PubMed Central

    Alshami, Issam; Alharbi, Ahmed E

    2014-01-01

    Objective To explore the prevention of recurrent candiduria using natural based approaches and to study the antimicrobial effect of Hibiscus sabdariffa (H. sabdariffa) extract and the biofilm forming capacity of Candida albicans strains in the present of the H. sabdariffa extract. Methods In this particular study, six strains of fluconazole resistant Candida albicans isolated from recurrent candiduria were used. The susceptibility of fungal isolates, time-kill curves and biofilm forming capacity in the present of the H. sabdariffa extract were determined. Results Various levels minimum inhibitory concentration of the extract were observed against all the isolates. Minimum inhibitory concentration values ranged from 0.5 to 2.0 mg/mL. Time-kill experiment demonstrated that the effect was fungistatic. The biofilm inhibition assay results showed that H. sabdariffa extract inhibited biofilm production of all the isolates. Conclusions The results of the study support the potential effect of H. sabdariffa extract for preventing recurrent candiduria and emphasize the significance of the plant extract approach as a potential antifungal agent. PMID:25182280

  4. 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

  5. Isolation and sequence of the gene encoding ornithine decarboxylase, SPE1, from Candida albicans by complementation of a spe1 delta strain of Saccharomyces cerevisiae.

    PubMed

    McNemar, M D; Gorman, J A; Buckley, H R

    1997-11-01

    The gene encoding ornithine decarboxylase, SPE1, from the pathogenic yeast Candida albicans has been isolated by complementation of an ornithine decarboxylase-negative (spe1 delta) strain of Saccharomyces cerevisiae. Four transformants, three of which contain plasmids with the SPE1 gene, were isolated by selection on polyamine-free medium. The C. albicans ornithine decarboxylase (ODC) showed high homology with other eukaryotic ODCs at both the amino acid and nucleic acid levels.

  6. Directed mutagenesis in Candida albicans: one-step gene disruption to isolate ura3 mutants

    SciTech Connect

    Kelly, R.; Miller, S.M.; Kurtz, M.B.; Kirsch, D.R.

    1987-01-01

    A method for introducing specific mutations into the diploid Candida albicans by one-step gene disruption and subsequent UV-induced recombination was developed. The cloned C. albicans URA3 gene was disrupted with the C. albicans ADE2 gene, and the linearized DNA was used for transformation of two ade2 mutants, SGY-129 and A81-Pu. Both an insertional inactivation of the URA3 gene and a disruption which results in a 4.0-kilobase deletion were made. Southern hybridization analyses demonstrated that the URA3 gene was disrupted on one of the chromosomal homologs in 15 of the 18 transformants analyzed. These analyses also revealed restriction site dimorphism of EcoRI at the URA3 locus which provides a unique marker to distinguish between chromosomal homologs. This enabled us to show that either homolog could be disrupted and that disrupted transformants of SGY-129 contained more than two copies of the URA3 locus. The A81-Pu transformants heterozygous for the ura3 mutations were rendered homozygous and Ura- by UV-induced recombination. The homozygosity of a deletion mutant and an insertion mutant was confirmed by Southern hybridization. Both mutants were transformed to Ura+ with plasmids containing the URA3 gene and in addition, were resistant to 5-fluoro-orotic acid, a characteristic of Saccharomyces cerevisiae ura3 mutants as well as of orotidine-5'-phosphate decarboxylase mutants of other organisms.

  7. Isolation and partial characterisation of a new antiproliferative substance from human leucocytes inhibiting growth of Candida albicans

    PubMed Central

    Naess-Andresen, C F; Ekeberg, D; Fagerhol, M K; Sandvik, K; Staahl, L

    2003-01-01

    Aim: To purify and partially characterise a fraction from human leucocytes containing a substance cytotoxic to Candida albicans. Methods: Leucocytes were isolated from the buffy coats of healthy blood donors. The cytotoxic factor (CF) was isolated from the soluble fraction of the cells. A cell lysate was passed through a filter with a cut off value of 3 kDa, and the filtrate was processed by anionic exchange chromatography and gel filtration. The purified CF was analysed for its chemical and biological properties. The cytotoxicity of CF was tested on C albicans grown on agar plates. Results: Mass spectrometry showed a molecular mass of 2.148 kDa. CF was found in polymorphonuclear neutrophilic cells only. No amino acids were detected, and a low ultraviolet absorbance at 260 nm and resistance to nuclease indicate the absence of nucleic acids. An anthrone test was positive for carbohydrate. The substance was soluble in water. CF showed a dose related cytotoxicity in the range of 0.1–1 mg/ml. The cytotoxic effect was abrogated by zinc ions. Preliminary testing indicated that CF also had cytotoxic effects against some bacteria. Conclusions: This report describes a factor from isolated human leucocytes that is cytotoxic to C albicans. The substance contains a carbohydrate moiety, whereas no amino acids were detected. The cytotoxicity can be abrogated by zinc ions in vitro. This substance is probably part of the repertoire by which leucocytes prevent infections. PMID:12890745

  8. Isolation, characterization and mechanism of action of an antimicrobial peptide from Lecythis pisonis seeds with inhibitory activity against Candida albicans.

    PubMed

    Vieira, Maria Eliza Brambila; Vasconcelos, Ilka Maria; Machado, Olga Lima Tavares; Gomes, Valdirene Moreira; Carvalho, André de Oliveira

    2015-09-01

    Antimicrobial peptides (AMPs) are produced by a range of organisms as a first line of defense against invaders or competitors. Owing to their broad antimicrobial activity, AMPs have attracted attention as a potential source of chemotherapeutic drugs. The increasing prevalence of infections caused by Candida species as opportunistic pathogens in immunocompromised patients requires new drugs. Lecythis pisonis is a Lecythydaceae tree that grows in Brazil. The AMPs produced by this tree have not been described previously. We describe the isolation of 12 fractions enriched in peptides from L. pisonis seeds. Of the 12 fractions, at 10 μg/ml, the F4 fraction had the strongest growth inhibitory effect (53.7%) in Candida albicans, in addition to a loss of viability of 94.9%. The F4 fraction was separated into seven sub-fractions by reversed-phase chromatography. The F4.7' fraction had the strongest activity at 10 μg/ml, inhibiting C. albicans growth by 38.5% and a 69.3% loss of viability. The peptide in F4.7' was sequenced and was found to be similar to plant defensins. For this reason, the peptide was named L. pisonis defensin 1 (Lp-Def1). The mechanism of action that is responsible for C. albicans inhibition by Lp-Def1 includes a slight increase of reactive oxygen species induction and a significant loss of mitochondrial function. The results described here support the future development of plant defensins, specifically Lp-Def1, as new therapeutic substances against fungi, especially C. albicans. © The Author 2015. Published by ABBS Editorial Office in association with Oxford University Press on behalf of the Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences.

  9. Genetic similarity and phenotypic diversity of commensal and pathogenic strains of Candida albicans isolated from the oral cavity.

    PubMed Central

    Hellstein, J; Vawter-Hugart, H; Fotos, P; Schmid, J; Soll, D R

    1993-01-01

    Colony phenotype and genetic similarity were assessed within and between groups of commensal and pathogenic strains of Candida albicans collected from the oral cavities of individuals in a single geographical locale. Thirty-eight percent of pathogenic isolates contained predominant or minor variant colony morphologies (other than smooth) when samples from the sites of infection were cultured on plates, while 16% of commensal isolates contained minor variant colony morphologies when samples from the sites of carriage were cultured. The genetic similarities of isolates within and between groups were assessed by DNA fingerprinting by using Southern blot hybridization with the fingerprinting probe Ca3 and analysis with the computer-assisted, automated Dendron system. Both the commensal and the pathogenic groups contained a major cluster of genetically similar C. albicans isolates representing 31 and 33% of the strains in the respective groups. When a combined dendrogram of both commensal and pathogenic isolates was generated, the major clusters of genetically similar isolates in each group mixed into one large cluster. Minor clusters in the individual dendrograms also mixed. These results suggest common clonal origins for commensal and pathogenic strains in the same geographical locale. Images PMID:8308110

  10. Genetic similarity and phenotypic diversity of commensal and pathogenic strains of Candida albicans isolated from the oral cavity.

    PubMed

    Hellstein, J; Vawter-Hugart, H; Fotos, P; Schmid, J; Soll, D R

    1993-12-01

    Colony phenotype and genetic similarity were assessed within and between groups of commensal and pathogenic strains of Candida albicans collected from the oral cavities of individuals in a single geographical locale. Thirty-eight percent of pathogenic isolates contained predominant or minor variant colony morphologies (other than smooth) when samples from the sites of infection were cultured on plates, while 16% of commensal isolates contained minor variant colony morphologies when samples from the sites of carriage were cultured. The genetic similarities of isolates within and between groups were assessed by DNA fingerprinting by using Southern blot hybridization with the fingerprinting probe Ca3 and analysis with the computer-assisted, automated Dendron system. Both the commensal and the pathogenic groups contained a major cluster of genetically similar C. albicans isolates representing 31 and 33% of the strains in the respective groups. When a combined dendrogram of both commensal and pathogenic isolates was generated, the major clusters of genetically similar isolates in each group mixed into one large cluster. Minor clusters in the individual dendrograms also mixed. These results suggest common clonal origins for commensal and pathogenic strains in the same geographical locale.

  11. Biotype stability of Candida albicans isolates after culture storage determined by randomly amplified polymorphic DNA and phenotypical methods.

    PubMed

    Bacelo, Katia Leston; da Costa, Karen Regina Carim; Ferreira, Joseane Cristina; Candido, Regina Celia

    2010-11-01

    Typing methods to evaluate isolates in relation to their phenotypical and molecular characteristics are essential in epidemiological studies. In this study, Candida albicans biotypes were determined before and after storage in order to verify their stability. Twenty C. albicans isolates were typed by Randomly Amplified Polymorphic DNA (RAPD), production of phospholipase and proteinase exoenzymes (enzymotyping) and morphotyping before and after 180 days of storage in Sabouraud dextrose agar (SDA) and sterilised distilled water. Before the storage, 19 RAPD patterns, two enzymotypes and eight morphotypes were identified. The fragment patterns obtained by RAPD, on the one hand, were not significantly altered after storage. On the other hand, the majority of the isolates changed their enzymotype and morphotype after storage. RAPD typing provided the better discriminatory index (DI) among isolates (DI = 0.995) and maintained the profile identified, thereby confirming its utility in epidemiological surveys. Based on the low reproducibility observed after storage in SDA and distilled water by morphotyping (DI = 0.853) and enzymotyping (DI = 0.521), the use of these techniques is not recommended on stored isolates.

  12. [Utility of Fluoroplate Candida for the rapid identification of Candida albicans].

    PubMed

    Quindós, G; San Millan, R; Bikandi, J; Pontón, J

    1996-12-01

    Candida albicans infections are frequent in immunocompromised patients and a prompt diagnosis could favor an early and proper antifungal treatment. The rapid identification of clinical yeast isolates facilitate this diagnosis. The utility of Fluoroplate Candida ready-to-use plates for Candida albicans rapid identification was evaluated with 653 clinical isolates from 23 yeast species, including 307 C. albicans plated onto Fluoroplate Candida agar (Merck, Germany). Rapid identification of C. albicans was based on the hydrolysis of 4-methylumbelliferyl-N-acetyl-beta-D-galactosaminide by the galactosaminidase activity of C. albicans producing white fluorescent colonies under ultraviolet light. Identification on Fluoroplate Candida was confirmed by germ tube, chlamydoconidia formation and API-ATB ID 32C assays. Three hundred and five of 306 isolates showing fluorescent colonies were C. albicans and one was Candida glabrata (false positive). The rest of the isolates showed colonies without fluorescence and with the exception of two false negatives, these isolates were identified as non-C. albicans by other methods. Fluoroplate Candida allows a rapid and excellent identification of C. albicans showing a sensitivity and specificity of 99.3 and 99.7%, respectively.

  13. β-Glucan Induces Reactive Oxygen Species Production in Human Neutrophils to Improve the Killing of Candida albicans and Candida glabrata Isolates from Vulvovaginal Candidiasis

    PubMed Central

    Bonfim-Mendonça, Patricia de Souza; Ratti, Bianca Altrão; Godoy, Janine da Silva Ribeiro; Negri, Melyssa; de Lima, Nayara Cristina Alves; Fiorini, Adriana; Hatanaka, Elaine; Consolaro, Marcia Edilaine Lopes; de Oliveira Silva, Sueli; Svidzinski, Terezinha Inez Estivalet

    2014-01-01

    Vulvovaginal candidiasis (VVC) is among the most prevalent vaginal diseases. Candida albicans is still the most prevalent species associated with this pathology, however, the prevalence of other Candida species, such as C. glabrata, is increasing. The pathogenesis of these infections has been intensely studied, nevertheless, no consensus has been reached on the pathogenicity of VVC. In addition, inappropriate treatment or the presence of resistant strains can lead to RVVC (vulvovaginal candidiasis recurrent). Immunomodulation therapy studies have become increasingly promising, including with the β-glucans. Thus, in the present study, we evaluated microbicidal activity, phagocytosis, intracellular oxidant species production, oxygen consumption, myeloperoxidase (MPO) activity, and the release of tumor necrosis factor α (TNF-α), interleukin-8 (IL-8), IL-1β, and IL-1Ra in neutrophils previously treated or not with β-glucan. In all of the assays, human neutrophils were challenged with C. albicans and C. glabrata isolated from vulvovaginal candidiasis. β-glucan significantly increased oxidant species production, suggesting that β-glucan may be an efficient immunomodulator that triggers an increase in the microbicidal response of neutrophils for both of the species isolated from vulvovaginal candidiasis. The effects of β-glucan appeared to be mainly related to the activation of reactive oxygen species and modulation of cytokine release. PMID:25229476

  14. 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.

  15. Fluconazole susceptibility and strain variation of Candida albicans isolates from HIV-infected patients with oropharyngeal candidosis.

    PubMed

    Barchiesi, F; Arzeni, D; Del Prete, M S; Sinicco, A; Falconi Di Francesco, L; Pasticci, M B; Lamura, L; Nuzzo, M M; Burzacchini, F; Coppola, S; Chiodo, F; Scalise, G

    1998-05-01

    Over a 16 month period we conducted a prospective study in a cohort of 45 HIV-positive patients to detect the development of resistance to fluconazole and to analyse the epidemiology of oropharyngeal candidosis (OPC). Each episode was treated with fluconazole 100 mg/day po for 10 days. All yeast isolates were tested for their in-vitro susceptibility to fluconazole. Multiple strains of Candida albicans simultaneously isolated from a given patient were typed by electrophoretic karyotyping. Overall, 106 episodes of OPC were diagnosed among the 45 patients: 18/45 patients (40%) had only one episode, 11/45 (24%) had two episodes, and the remaining 16/45 (36%) had three or more episodes (range 3-7). Cure (complete resolution of signs and symptoms and negative post-treatment cultures) and improvement (complete resolution of signs and symptoms but positive post-treatment cultures) were observed in 30/106 (28%) and 69/106 (65%) episodes of OPC, respectively. Failure (absence of improvement or exacerbation of signs and symptoms) was observed in seven episodes (7%) from four patients. In two of these four patients a significant and progressive increase in fluconazole MICs was observed: from 0.25 to 16 mg/L in one patient, and from < or = 0.125 to 32 mg/L in the second one. Tests on multiple colonies from individual isolation plates showed that it was not unusual to obtain different fluconazole MICs, indicating that, in order to avoid misleading results, one should perform in-vitro susceptibility testing by using a multiple colony inoculum rather than an inoculum made from a single colony. A total of 213 strains of C. albicans isolated from seven patients who suffered from four or more episodes of OPC through the course of the study were typed by electrophoretic karyotyping. Five individuals (71%) were infected with yeasts with only one DNA type, while the other two patients showed the presence of two or three different DNA types. The simultaneous presence of multiple types

  16. Enhanced extracellular production of aspartyl proteinase, a virulence factor, by Candida albicans isolates following growth in subinhibitory concentrations of fluconazole.

    PubMed

    Wu, T; Wright, K; Hurst, S F; Morrison, C J

    2000-05-01

    We examined the production of secreted aspartyl proteinase (Sap), a putative virulence factor of Candida albicans, by a series of 17 isolates representing a single strain obtained from the oral cavity of an AIDS patient before and after the development of clinical and in vitro resistance to fluconazole. Isolates were grown in Sap-inducing yeast carbon base-bovine serum albumin medium containing 0, 0.25, 0.5, or 1 MIC of fluconazole, and cultures were sampled daily for 14 days to determine extracellular Sap activity by enzymatic degradation of bovine serum albumin. Extracellular Sap activity was significantly decreased in a dose-dependent manner for the most fluconazole-susceptible isolate (MIC, 1.0 microg/ml) and significantly increased in a dose-dependent manner for the most fluconazole-resistant isolate (MIC, >64 microg/ml). Enhanced extracellular Sap production could not be attributed to cell death or nonspecific release of Sap, because there was no reduction in the number of CFU and no significant release of enolase, a constitutive enzyme of the glycolytic pathway. Conversely, intracellular Sap concentrations were significantly increased in a dose-dependent manner in the most fluconazole-susceptible isolate and decreased in the most fluconazole-resistant isolate. Enhanced Sap production correlated with the overexpression of a gene encoding a multidrug resistance (MDR1) efflux pump occurring in these isolates. These data indicate that exposure to subinhibitory concentrations of fluconazole can result in enhanced extracellular production of Sap by isolates with the capacity to overexpress MDR1 and imply that patients infected with these isolates and subsequently treated with suboptimal doses of fluconazole may experience enhanced C. albicans virulence in vivo.

  17. 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

  18. Multilocus sequence typing (MLST) analysis of Candida albicans isolates colonizing acrylic dentures before and after denture replacement.

    PubMed

    Choo, Khai How; Lee, Hee Ji; Knight, Nicholas J; Holmes, Ann R; Cannon, Richard D

    2017-08-01

    Yeast, in particular Candida albicans, are the principal fungal cause of denture stomatitis, and can also be present as a commensal in many individuals. Few studies, however, have examined oral retention of yeast strains over time. We analyzed the yeast present in saliva samples and from the dentures of 10 individuals colonized with yeast but with no signs of stomatitis, before new complete maxillary dentures were fitted and also at 1, 3, and 6 months after denture replacement. Yeast species were presumptively identified on selective agar plates and were present in nine individuals before denture replacement and in six at the 6-month time point. C. albicans was detected in seven individuals pre-replacement, and in three by 6 months post-replacement. Sixty-two isolates (up to five from each C. albicans-positive sample) were analyzed by multilocus sequence typing (MLST) (33 from saliva and 29 from dentures). Six MLST allele profiles were identified that were common to several individuals. These profiles included three previously reported diploid sequence types (DSTs) and three novel DSTs. Two of the novel DSTs were closely related variants of a previously reported DST, and both showed loss of heterozygosity polymorphisms within one of the seven MLST gene sequences. For three individuals, at least one DST that was present before denture replacement was still detected in either saliva or on dentures at subsequent sampling times. Our results indicate that denture replacement reduces but does not remove, colonising yeast and confirm previous observations of C. albicans strain microevolution. © The Author 2016. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  19. Platelet interactions with Candida albicans.

    PubMed Central

    Skerl, K G; Calderone, R A; Sreevalsan, T

    1981-01-01

    The interaction of human platelets and Candida albicans was studied. Platelet-rich plasma was obtained from freshly drawn blood or outdated platelet concentrates. From the platelet-rich plasma, a platelet extract was derived which stimulated germ tube formation by C. albicans when incubated with yeast cells at 37 degrees C. The active component(s) was heat stable, trypsin sensitive, and ribonuclease and deoxyribonuclease insensitive, and possessed cationic properties since it readily attached to carboxymethyl-Sephadex. The active component(s) seemed to bind to heparin also, since germ tube-promoting activity was eluted from a heparin-cyanogen bromide-activated Sepharose 4B column. In addition, platelet-derived growth factor (Collaborative Research, Inc.) stimulated germination when incubated with low amounts (0.4% final concentration) of bovine calf serum. The aggregation of platelets, prepared as platelet-rich plasma by C. albicans cell wall or alkali-extracted cell wall fractions, was also studied. Aggregation of platelets was observed when cell wall or cell wall fractions were incubated with platelet-poor plasma at 37 degrees C for 20 min and then added to platelet-rich plasma. The component of platelet-poor plasma which promoted aggregation of platelets by C. albicans cell wall or alkali-extracted fractions was inactivated at 56 degrees C (30 min) and by cobra venom factor, indicating a role for the alternate complement pathway in the aggregation response. PMID:7037646

  20. 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.

  1. Molecular Phylogenetic Analysis of a Geographically and Temporally Matched Set of Candida albicans Isolates from Humans and Nonmigratory Wildlife in Central Illinois ▿

    PubMed Central

    Wrobel, Lauren; Whittington, Julia K.; Pujol, Claude; Oh, Soon-Hwan; Ruiz, Marilyn O.; Pfaller, Michael A.; Diekema, Daniel J.; Soll, David R.; Hoyer, Lois L.

    2008-01-01

    This study explored whether wildlife species serve as the reservoir for human Candida albicans strains in a given geographic area. C. albicans isolates were collected from nonmigratory wildlife admitted to the University of Illinois Wildlife Medical Clinic. A geographically and temporally matched set of C. albicans oral isolates was collected from healthy human volunteers. Multilocus sequence typing was used to assign strains to genetic clades. Clade 1 isolates, particularly diploid sequence type 69 (DST 69), were most common in humans. Clade 1 strains were less frequently recovered from wildlife, while clade 8 strains, particularly DST 90, were overrepresented in the wildlife collection. All instances where a wildlife and human isolate shared the same DST occurred within clade 1. Clade distributions between human and wildlife isolates were significantly different, demonstrating population isolation between the groups. These differences may indicate limited strain transfer between groups or differential selection of C. albicans isolates in humans and wildlife. Wildlife strains had an amphotericin B MIC significantly lower than that of human isolates; strains with increased susceptibility were from several clades. C. albicans isolates were collected from domestic animals to provide comparisons with human and wildlife data sets. C. albicans isolation from canine and feline oral and anal swabs was infrequent; companion animal isolates were closely related to clade 1 human isolates. Collectively, the data suggest a greater likelihood of C. albicans transfer from humans to animals than from animals to humans. The nontransient human population may maintain the connection between geography and the C. albicans genetic groups recovered from humans. PMID:18621922

  2. Paradoxical antifungal activity and structural observations in biofilms formed by echinocandin-resistant Candida albicans clinical isolates.

    PubMed

    Walraven, Carla J; Bernardo, Stella M; Wiederhold, Nathan P; Lee, Samuel A

    2014-02-01

    Echinocandin-resistant clinical isolates of Candida albicans have been reported, and key-hot spot mutations in the FKS1 gene, which encodes a major glucan synthase subunit, have been identified in these (caspofungin-resistant [CAS-R]) strains. Although these mutations result in phenotypic resistance to echinocandins in planktonic cells, there is little data on antifungal susceptibilities of CAS-R C. albicans strains within biofilms. Thus, we analyzed biofilms formed by 12 C. albicans CAS-R clinical strains in which we previously identified FKS1 hot-spot mutations and compared the sessile antifungal and paradoxical activity of anidulafungin (ANID), caspofungin (CAS), and micafungin (MICA). Biofilms were formed in a 96-well static microplate model and assayed using both tetrazolium-salt reduction and crystal violet assays, as well as examination by scanning electron microscopy. We first sought to assess biofilm formation and structure in these fks1 mutants and found that the biofilm mass and metabolic activities were reduced in most of the fks1 mutants as compared with reference strain SC5314. Structural analyses revealed that the fks1 mutant biofilms were generally less dense and had a clear predominance of yeast and pseudohyphae, with unusual "pit"-like cell surface structures. We also noted that sessile minimum inhibitory concentrations (MICs) to ANID, CAS, and MICA were higher than planktonic MICs of all but one strain. The majority of strains demonstrated a paradoxical effect (PE) to particular echinocandins, in either planktonic or sessile forms. Overall, biofilms formed by echinocandin-resistant clinical isolates demonstrated varied PEs to echinocandins and were structurally characterized by a preponderance of yeast, pseudohyphae, and pit-like structures.

  3. Paradoxical antifungal activity and structural observations in biofilms formed by echinocandin-resistant Candida albicans clinical isolates

    PubMed Central

    Wiederhold, Nathan P.; Lee, Samuel A.

    2016-01-01

    Echinocandin-resistant clinical isolates of Candida albicans have been reported, and key-hot spot mutations in the FKS1 gene, which encodes a major glucan synthase subunit, have been identified in these (caspofungin-resistant [CAS-R]) strains. Although these mutations result in phenotypic resistance to echinocandins in planktonic cells, there is little data on antifungal susceptibilities of CAS-R C. albicans strains within biofilms. Thus, we analyzed biofilms formed by 12 C. albicans CAS-R clinical strains in which we previously identified FKS1 hot-spot mutations and compared the sessile antifungal and paradoxical activity of anidulafungin (ANID), caspofungin (CAS), and micafungin (MICA). Biofilms were formed in a 96-well static microplate model and assayed using both tetrazolium-salt reduction and crystal violet assays, as well as examination by scanning electron microscopy. We first sought to assess biofilm formation and structure in these fks1 mutants and found that the biofilm mass and metabolic activities were reduced in most of the fks1 mutants as compared with reference strain SC5314. Structural analyses revealed that the fks1 mutant biofilms were generally less dense and had a clear predominance of yeast and pseudohyphae, with unusual “pit”-like cell surface structures. We also noted that sessile minimum inhibitory concentrations (MICs) to ANID, CAS, and MICA were higher than planktonic MICs of all but one strain. The majority of strains demonstrated a paradoxical effect (PE) to particular echinocandins, in either planktonic or sessile forms. Overall, biofilms formed by echinocandin-resistant clinical isolates demonstrated varied PEs to echinocandins and were structurally characterized by a preponderance of yeast, pseudohyphae, and pit-like structures. PMID:24576999

  4. Effect of plant oils on Candida albicans.

    PubMed

    Agarwal, Vishnu; Lal, Priyanka; Pruthi, Vikas

    2010-10-01

    Candida species, notably Candida albicans, is the major fungal pathogen in humans. It is a dimorphic fungus capable of causing superficial mucosal infections, as well as systemic infections, in immunocompromised individuals. The factors responsible for its pathogenesis are still not fully understood and increasing resistance to commonly used antifungal agents necessitates the search for new formulations. The inhibitory effect of 30 different plant oils on Candida albicans isolated from clinical samples was evaluated. The antifungal agent fluconazole was used as a positive control. Plant oils were tested at concentrations from 0.03% to 3% (v/v) to determine the minimum inhibitory concentration and minimum fungicidal concentration (MFC) using agar dilution and macro broth dilution assays. Of the 30 plant oils tested, 18 were found to be effective and 12 were ineffective. Based on their MFCs, effective oils were placed into three categories: most effective, moderately effective and least effective. Eucalyptus and peppermint oils were most effective, with MFC values of 0.12% and 0.15% (v/v), respectively. The significant antifungal activity of these oils suggests that they could serve as a source of compounds with therapeutic potential against Candida-related infections. Copyright © 2010 Taiwan Society of Microbiology. Published by Elsevier B.V. All rights reserved.

  5. An MDR1 promoter allele with higher promoter activity is common in clinically isolated strains of Candida albicans

    PubMed Central

    Bruzual, Igor

    2013-01-01

    In the opportunistic fungal pathogen Candida albicans, up-regulation of MDR1, encoding an efflux transporter, leads to increased resistance to the antifungal drug fluconazole. Antifungal resistance has been linked to several types of genetic change in C. albicans, including changes in genome structure, genetic alteration of the drug target, and overexpression of transporters. High-level over-expression of MDR1 is commonly mediated by mutation in a trans-acting factor, Mrr1p. This report describes a second mechanism that contributes to up-regulation of MDR1 expression. By analyzing the sequence of the MDR1 promoter region in fluconazole-resistant and fluconazole-susceptible strains, we identified sequence polymorphisms that defined two linkage groups, corresponding to the two alleles in the diploid genome. One of the alleles conferred higher MDR1 expression compared with the other allele. Strains in which both alleles were of the higher activity type were common in collections of clinically isolated strains while strains carrying only the less active allele were rare. As increased expression of MDR1 confers higher resistance to drugs, strains with the more active MDR1 promoter allele may grow or survive longer when exposed to drugs or other selective pressures, providing greater opportunity for mutations that confer high-level drug resistance to arise. Through this mechanism, higher activity alleles of the MDR1 promoter could promote the development of drug resistance. PMID:21972105

  6. 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

  7. [Candida: epidemiology and risk factors for non-albicans species].

    PubMed

    Cornistein, Wanda; Mora, Andrea; Orellana, Nora; Capparelli, Federico Javier; del Castillo, Marcelo

    2013-01-01

    Nosocomial fungal infections have increased significantly in the last decade. Candida detection in clinical specimens can mean either colonization or an infection which can be local (muguet) or invasive. Knowledge of the species helps in choosing the best treatment. The aims of this study were to determine the frequency and distribution of Candida species detected in clinical samples, to analyze the clinical characteristics of the involved population and to determine the risk factors for Candida non-albicans species. Retrospective, observational. 2006-2010. all isolates of Candida in clinical specimens from patients hospitalized at least 48 hours in a neurological center. We analyzed epidemiological characteristics, co morbidities, risk factors, factors associated with Candida non-albicans detection, antifungal treatment, development of adverse events and mortality. Candida spp. was isolated from 321 clinical specimens: 139 (43.3%) were C. albicans and 182 (56.7%) Candida non-albicans. The distribution of the sample was: urine 122 (Candida non-albicans 67.2%), airway 81, oropharynx 45 (C. albicans) and candidemia 40 (Candida non-albicans 75%). The most frequent co-morbidity was solid tumor (35.5%). The main risk factors were antibiotic therapy (85.5%), steroid therapy (61.7%) and in ICU at diagnosis (61.6%). The analysis of risk factors and the isolation of Candida non-albicans shows that chemotherapy, previous surgery, treatment with aminopenicillins, carbapenems and glycopeptides were statistically significant (P<.05). There is a trend in neutropenic patients (P=.055) and in ICU at diagnosis (P=.076). Overall survival was 71%. Candida species distribution varies with the type of sample analyzed. Non-albicans species make up the majority of the isolates. The identification of the species involved per sample helps to optimize treatment. The high frequency of isolation of Candida in patients on steroids and antibiotics and admitted to ICU, is worth pointing out

  8. Biofilms formed by Candida albicans bloodstream isolates display phenotypic and transcriptional heterogeneity that are associated with resistance and pathogenicity

    PubMed Central

    2014-01-01

    Background Candida albicans infections have become increasingly recognised as being biofilm related. Recent studies have shown that there is a relationship between biofilm formation and poor clinical outcomes in patients infected with biofilm proficient strains. Here we have investigated a panel of clinical isolates in an attempt to evaluate their phenotypic and transcriptional properties in an attempt to differentiate and define levels of biofilm formation. Results Biofilm formation was shown to be heterogeneous; with isolates being defined as either high or low biofilm formers (LBF and HBF) based on different biomass quantification. These categories could also be differentiated using a cell surface hydrophobicity assay with 24 h biofilms. HBF isolates were more resistance to amphotericin B (AMB) treatment than LBF, but not voriconazole (VRZ). In a Galleria mellonella model of infection HBF mortality was significantly increased in comparison to LBF. Histological analysis of the HBF showed hyphal elements intertwined indicative of the biofilm phenotype. Transcriptional analysis of 23 genes implicated in biofilm formation showed no significant differential expression profiles between LBF and HBF, except for Cdr1 at 4 and 24 h. Cluster analysis showed similar patterns of expression for different functional classes of genes, though correlation analysis of the 4 h biofilms with overall biomass at 24 h showed that 7 genes were correlated with high levels of biofilm, including Als3, Eap1, Cph1, Sap5, Plb1, Cdr1 and Zap1. Conclusions Our findings show that biofilm formation is variable amongst C. albicans isolates, and categorising isolates depending on this can be used to predict how pathogenic the isolate will behave clinically. We have shown that looking at individual genes in less informative than looking at multiple genes when trying to categorise isolates at LBF or HBF. These findings are important when developing biofilm-specific diagnostics as these could be

  9. In vivo direct interaction of the antibiotic primycin on a Candida albicans clinical isolate and its ergosterol-less mutant.

    PubMed

    Virág, Eszter; Juhász, A; Kardos, R; Gazdag, Z; Papp, G; Pénzes, Agota; Nyitrai, M; Vágvölgyi, Cs; Pesti, M

    2012-03-01

    Interaction of primycin antibiotic with plasma membrane, and its indirect biological effects were investigated in this study. The antifungal activity of primycin against 13 human pathogenic Candida ATCC and CBS reference species and 74 other Candida albicans clinical isolates was investigated with a microdilution technique. No primycin-resistant strain was detected. Direct interaction of primycin with the plasma membrane was demonstrated for the first time by using an ergosterol-producing strain 33erg+ and its ergosterol-less mutant erg-2. In growth inhibition tests, the 33erg+ strain proved to be more sensitive to primycin than its erg-2 mutant, indicating the importance of the plasma membrane composition in primycin-induced processes. The 64 μg ml-1 (56.8 nM) primycin treatment induced an enhanced membrane fluidity and altered plasma membrane dynamics, as measured by steady-state fluorescence anisotropy applying a trimethylammonium-diphenylhexatriene (TMA-DPH) fluorescence polarization probe. The following consequences were detected. The plasma membrane of the cells lost its barrier function, and the efflux of 260-nm-absorbing materials from treated cells of both strains was 1.5-1.8 times more than that for the control. Depending on the primycin concentration, the cells exhibited unipolar budding, pseudohyphae formation, and a rough cell surface visualized by scanning electron microscopy.

  10. A Combination Fluorescence Assay Demonstrates Increased Efflux Pump Activity as a Resistance Mechanism in Azole-Resistant Vaginal Candida albicans Isolates

    PubMed Central

    Bhattacharya, Somanon; Sobel, Jack D.

    2016-01-01

    Candida albicans is a pathogenic fungus causing vulvovaginal candidiasis (VVC). Azole drugs, such as fluconazole, are the most common treatment for these infections. Recently, azole-resistant vaginal C. albicans isolates have been detected in patients with recurring and refractory vaginal infections. However, the mechanisms of resistance in vaginal C. albicans isolates have not been studied in detail. In oral and systemic resistant isolates, overexpression of the ABC transporters Cdr1p and Cdr2p and the major facilitator transporter Mdr1p is associated with resistance. Sixteen fluconazole-susceptible and 22 fluconazole-resistant vaginal C. albicans isolates were obtained, including six matched sets containing a susceptible and a resistant isolate, from individual patients. Using quantitative real-time reverse transcriptase PCR (qRT-PCR), 16 of 22 resistant isolates showed overexpression of at least one efflux pump gene, while only 1 of 16 susceptible isolates showed such overexpression. To evaluate the pump activity associated with overexpression, an assay that combined data from two separate fluorescent assays using rhodamine 6G and alanine β-naphthylamide was developed. The qRT-PCR results and activity assay results were in good agreement. This combination of two fluorescent assays can be used to study efflux pumps as resistance mechanisms in clinical isolates. These results demonstrate that efflux pumps are a significant resistance mechanism in vaginal C. albicans isolates. PMID:27431223

  11. In vitro synergistic efficacy of combination of amphotericin B with Myrtus communis essential oil against clinical isolates of Candida albicans.

    PubMed

    Mahboubi, M; Ghazian Bidgoli, F

    2010-08-01

    In this study, we evaluated the antifungal activity of the essential oil from Myrtus communis (myrtle) leaves against Candida albicans (eight clinical isolates and one ATCC type strains) and different species of Aspergillus sp (A. niger, A. parasiticus, six isolates of Aspergillus flavus) using broth micro dilution assay. In addition, we evaluated the synergistic effect between the essential oil and the antifungal compound amphotericin B by checkboard micro titer assay. The essential oil was obtained from myrtle leaves by hydrodistillation method and the oil was analyzed by GC and GC-MS methods. Chemical analysis of oil revealed the presence of 70 components, representing 99.23% of the total oil. 1,8-cineole (36.1%), alpha-pinene (22.5%), linalool (8.4%), bornyl acetate (5.2%), alpha-terpineol (4.4%), linalyl acetate (4.2%) and limonene (3.8%) were found to be the major components of the oil. The antifungal evaluating showed that myrtle oil exhibited good antifungal activity against fungi. Myrtle oil showed significant antifungal activity when combined with amphotericin B.

  12. 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 Central

    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. PMID:24058485

  13. 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.

  14. Overexpression and mutation as a genetic mechanism of fluconazole resistance in Candida albicans isolated from human immunodeficiency virus patients in Indonesia.

    PubMed

    Rosana, Yeva; Yasmon, Andi; Lestari, Delly Chipta

    2015-09-01

    Fluconazole is the standard treatment for oropharyngeal candidiasis, which is the third most common opportunistic infection in human immunodeficiency virus (HIV)/AIDS patients in Indonesia. Overuse of this drug could lead to the emergence of resistance. The objective of this study was to analyse the role of ERG11, CDR1, CDR2 and MDR1 gene overexpression and mutations in the ERG11 gene as a genetic mechanism of fluconazole resistance in Candida albicans isolated from HIV patients in Indonesia. Overexpression of ERG11, CDR1, CDR2 and MDR1 was analysed by real-time reverse transcription PCR, while ERG11 gene mutation analysis was performed using sequencing methods. Seventeen isolates out of 92 strains of C. albicans isolated from 108 HIV patients were found to be resistant to azole antifungals. The highest gene overexpression of ERG11 was found in C. albicans resistant to single fluconazole, while the highest gene overexpression of CDR2 was detected in all isolates of C. albicans resistant to multiple azoles. Amino acid substitutions were observed at six positions, i.e. D116E, D153E, I261V, E266D, V437I and V488I. The amino acid substitution I261V was identified in this study and was probably associated with fluconazole resistance. The combination of overexpression of CDR2 and ERG11 and mutation in the ERG11 gene was found to be a genetic mechanism of fluconazole resistance in C. albicans isolated from HIV patients in Indonesia.

  15. Susceptibility of Candida albicans from Cystic Fibrosis Patients.

    PubMed

    Sabino, Raquel; Carolino, Elisabete; Moss, Richard B; Banaei, Niaz; Verissimo, Cristina; Stevens, David A

    2017-04-18

    Candida albicans is a common microbe, colonizer and potential pathogen found in respiratory cultures of cystic fibrosis (CF) patients. Because of possible development of resistance in patient isolates resulting from residence in the abnormal milieu of CF patient airways, or from exposure to antifungals, and considering the possibility of patient-to-patient spread of microbes and reports of elevated resistance to other fungal pathogens, it was important to assay the susceptibility of isolates of Candida and compare that profile to isolates from the community. In our center, and unlike another fungal pathogen, no increase in resistance of Candida isolates of the CF cohort was found.

  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. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Antifungal effects of Lavandula binaludensis and Cuminum cyminum essential oils against Candida albicans strains isolated from patients with recurrent vulvovaginal candidiasis.

    PubMed

    Minooeianhaghighi, M H; Sepehrian, L; Shokri, H

    2017-03-01

    Recurrent vulvovaginal candidiasis (RVVC), which affects approximately 5% of women of reproductive age, is defined as 4 or more episodes of symptomatic Candida vaginitis within a year. The purposes of this study were to determine the chemical compositions and antifungal susceptibility of Cuminum cyminum (C. cyminum) and Lavandula binaludensis (L. binaludensis) essential oils and their combination against Candida albicans (C. albicans) strains isolated from patients with RVVC. C. albicans isolates were identified via germ tube test, CHROMagar and RapID Yeast Plus System. The essential oils were obtained by hydrodistillation in a Clevenger apparatus and analyzed by gas chromatography-mass spectroscopy (GC-MS). The broth microdilution method was used as antifungal susceptibility test (CLSI-M27-A3). The GC-MS analysis allowed 13 components to be determined; the main components of C. cyminum and L. binaludensis essential oils were γ-terpinene (21.07%) and 1,8-cineole (71.56%), respectively. L. binaludensis and C. cyminum oils were effective in inhibiting C. albicans growth at mean concentrations of 7.91±1.61μg/mL and 8.00±1.89μg/mL, respectively. In addition, the combination of C. cyminum with L. binaludensis oils were more active causing inhibition in all C. albicans isolates, with concentrations varying from 3.90 to 11.71μg/mL (mean value: 7.22±1.69μg/mL). The results suggested the potential substitution of the antifungal chemicals by C. cyminum and L. binaludensis essential oils as natural inhibitors to control the growth of the most important pathogenic Candida species and alternative therapies for RVVC. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  18. Recurrent episodes of Candidemia due to Candida glabrata, Candida tropicalis and Candida albicans with acquired echinocandin resistance.

    PubMed

    Grosset, Marine; Desnos-Ollivier, Marie; Godet, Cendrine; Kauffmann-Lacroix, Catherine; Cazenave-Roblot, France

    2016-12-01

    Mixed fungal infection and acquired echinocandin resistance of Candida spp. remain infrequent. In this study we have reported the case of a patient hospitalized for tuberculosis who experienced multiple infections due to three common Candida species (C. albicans, C. glabrata, C. tropicalis). Furthermore, consecutive isolates from blood cultures and heart valve were found resistant to azoles (C. tropicalis) and to echinocandin with either novel (C. tropicalis) or previously described (C. albicans) missense mutations in the Fks gene.

  19. Reliability of the agar based method to assess the production of degradative enzymes in clinical isolates of Candida albicans.

    PubMed

    Arantes, Paula Tamião; Sanitá, Paula Volpato; Santezi, Carolina; Barbeiro, Camila de Oliveira; Reina, Bárbara Donadon; Vergani, Carlos Eduardo; Dovigo, Lívia Nordi

    2016-03-01

    The aim of this study was to establish a reproducible protocol using the methodology of hyaline zones around the colonies on specific agar plates for phospholipase and proteinase production. This was an in vitro double-blind experiment, in which the dependent variables were the enzymatic activity measurements (Pz) for the production of phospholipase (Pz-ph) and the production of secreted aspartyl proteinases (Pz-sap). Three independent variables give rise to different measurement protocols. All measurements were carried out at two different moments by four examiners (E1, E2, E3, and E4). The minimum sample size was 30 Candida albicans clinical isolates. Specific agar plates for phospholipase and SAPs production were prepared according the literature. The intra-and inter-examiner reproducibility for each protocol was estimated using the Intraclass Correlation Coefficient (ICC) and its confidence interval (95% CI). Based on the results obtained for both phospholipase and SAPs, there appears to be no consensus on the protocol chosen for each particular examiner. Measuring the colonies in triplicate may be the main factor associated with the increase in measurement accuracy and should therefore take precedence over measuring only one colony. When only one examiner is responsible for taking measurements, a standard protocol should be put in place and the statistical calibration of this researcher should be done prior to data collection. However, if two or more researchers are involved in the assessment of agar plates, our results suggest that the protocols using software to undertake plate reading is preferred.

  20. Prevalence of Candida albicans, Candida dubliniensis and Candida africana in pregnant women suffering from vulvovaginal candidiasis in Argentina.

    PubMed

    Mucci, María Josefina; Cuestas, María Luján; Landanburu, María Fernanda; Mujica, María Teresa

    Vulvovaginal candidiasis (VVC) is a vulvovaginitis commonly diagnosed in gynecology care. In recent years, the taxonomy of the most important pathogenic Candida species, such as Candida albicans have undergone significant changes. This study examined the prevalence of C. albicans, Candida africana, and Candida dubliniensis in vaginal specimens from 210 pregnant women suffering from vulvovaginitis or having asymptomatic colonization. Phenotypic and molecular methods were used for the identification of the species. During the studied period, 55 isolates of Candida or other yeasts were obtained from specimens collected from 52 patients suffering from vulvovaginitis (24.8%). C. albicans was the predominant Candida species in 42 isolates (80.7%), either alone or in combination with other species of the genus (5.7%, n=3). Additionally, nine isolates of C. albicans (50%) were obtained from asymptomatic patients (n=18). C. dubliniensis was the causative agent in 2 (3.8%) cases of VVC, and was also isolated in one asymptomatic patient. Molecular assays were carried out using specific PCR to amplify the ACT1-associated intron sequence of C. dubliniensis. The amplification of the HWP1 gene also correctly identified isolates of the species C. albicans and C. dubliniensis. No C. africana was isolated in this work. Some C. albicans isolates were either homozygous or heterozygous at the HWP1 locus. The distribution of heterozygous and homozygous C. albicans isolates at the HWP1 locus was very similar among patients suffering from VVC and asymptomatic patients (p=0.897). The presence of C. albicans and C. dubliniensis, and the absence of C. africana in pregnant is noteworthy. Copyright © 2016 Asociación Española de Micología. Publicado por Elsevier España, S.L.U. All rights reserved.

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

    PubMed Central

    Whibley, Natasha; Gaffen, Sarah L.

    2015-01-01

    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 C. 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. PMID:26276374

  2. 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.

  3. Plasticity of Candida albicans Biofilms

    PubMed Central

    Daniels, Karla J.

    2016-01-01

    SUMMARY Candida albicans, the most pervasive fungal pathogen that colonizes humans, forms biofilms that are architecturally complex. They consist of a basal yeast cell polylayer and an upper region of hyphae encapsulated in extracellular matrix. However, biofilms formed in vitro vary as a result of the different conditions employed in models, the methods used to assess biofilm formation, strain differences, and, in a most dramatic fashion, the configuration of the mating type locus (MTL). Therefore, integrating data from different studies can lead to problems of interpretation if such variability is not taken into account. Here we review the conditions and factors that cause biofilm variation, with the goal of engendering awareness that more attention must be paid to the strains employed, the methods used to assess biofilm development, every aspect of the model employed, and the configuration of the MTL locus. We end by posing a set of questions that may be asked in comparing the results of different studies and developing protocols for new ones. This review should engender the notion that not all biofilms are created equal. PMID:27250770

  4. [Inhibitory effects of butyl alcohol extract of Baitouweng decoction on yeast-to-hyphae transition of Candida albicans isolates from VVC in alkaline pH environment].

    PubMed

    Zhang, Meng-xiang; Xia, Dan; Shi, Gao-xiang; Shao, Jing; Wang, Tian-ming; Tang, Chuan-chao; Wang, Chang-zhong

    2015-02-01

    To investigate the effects of butyl alcohol extract of Baitouweng decoction ( BAEB) on yeast-to-hyphae transition of Candida albicans isolates from vulvovaginal candidiasis (VVC) in alkaline pH. Serial 2-fold dilution assay was used to determine the minimal inhibitory concentrations (MICs) of Baitouweng decoction extracts against C. albicans isolates from VVC, XTT assay was applied to determine the metabolic activity of C. albicans hypha treated by BAEB for 6 h. The morphological change of C. albicans treated by BAEB was inspected at different pH by inverted microscope, fluorescence microscope, scanning electron microscopy (SEM). Solid agar plate and semi-solid agar were utilized to evaluate colony morphology and invasive growth of C. albicans, respectively. Quantitative Real-time PCR (qRT-PCR) was adopted to observe the expressions of hyphae-specific genes including HWP1, ALS3, CSH1, SUN41 and CaPDE2. The MIC of BAEB against C. albicans is less than that of other extracts; hyphae grow best at pH 8. 0; 512 mg · L(-1) and 1,024 mg · L(-1) BAEB could inhibit formation of hyphae and influence colony morphology. When treated by 512 mg · L(-1) and 1,024 mg · L(-1) BAEB, the colonies became smooth; while by 0 and 256 mg · L(-1) BAEB, the colonies became wrinkled. In semi-solid agar, the length of hyphae decreased steadily as the concentration of BAEB lowered. The expression of HWP1, ALS3, CSHl, SUN41 were downregulated by 5.12, 4.26, 3.2 and 2.74 folds, and CaPDE2 was upregulated by 2.38 fold. BAEB could inhibit yeast-to-hyphae transition of C. albicans isolates from VVC in alkaline pH.

  5. 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

  6. Comparison of four molecular typing methods for evaluating genetic diversity among Candida albicans isolates from human immunodeficiency virus-positive patients with oral candidiasis.

    PubMed Central

    Díaz-Guerra, T M; Martínez-Suárez, J V; Laguna, F; Rodríguez-Tudela, J L

    1997-01-01

    Candida albicans strain delineation by karyotyping. NotI restriction pattern analysis, hybridization with specific probe 27A, and PCR fingerprinting with the phage M13 core sequence were performed with 30 isolates from the oral cavities of 30 human immunodeficiency virus (HIV)-infected patients and 8 reference strains. Within the panel of clinical isolates, 20 were geographically related, although 10 isolates were susceptible to fluconazole and 10 isolates were resistant to fluconazole. The remaining isolates used in this study were fluconazole resistant and geographically unrelated. A composite DNA type was defined for each of the strains as the combination of types obtained by the four molecular methods. By this procedure, a great diversity of DNA types was found among isolates from the oropharynges of HIV-infected individuals with oral candidiasis. This diversity was not reduced when isolates were evaluated on the basis of whether they came from the same geographical locale and whether they were fluconazole resistant. These data refute the idea of a clonal origin for fluconazole-resistant strains among HIV-positive patients. Karyotyping was the least discriminatory method, yielding 19 DNA types among the 38 strains analyzed. Conversely, hybridization with the 27A probe showed a unique DNA pattern for each of the strains examined in this study. Our results demonstrate that at least two different molecular methods are needed for Candida albicans typing and that there is a great deal of strain variation within the species, irrespective of place of origin or antifungal resistance patterns. PMID:9157142

  7. 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

  8. Prevalence of yeast other than Candida albicans in denture wearers.

    PubMed

    Cavaleiro, Inês; Proença, Luis; Félix, Sérgio; Salema-Oom, Madalena

    2013-07-01

    The isolation of yeast species other than Candida albicans from the oral mucosa has been increasing in frequency, suggesting that those may constitute emerging potential oral colonizers. The purpose of this work was to determine whether yeast species other than C. albicans are associated with factors related to wearing of dental prostheses. tRNA-PCR fingerprinting and sequencing of the 26S rDNA D1/D2 domain were used to identify all yeasts isolated from CHROMagar™ Candida cultures of oral swabs collected from 178 patients. Besides C. albicans, 13 other species were identified, corresponding to 34% of the yeast isolates. The majority of the non-C. albicans species were not detected as single colonizers but rather in co-colonization with one or two other yeasts, often with C. albicans. No significant associations were found with non-C. albicans species. On the contrary, the best-fitted logistic regression model predicts that either wearing a denture (adjusted odds = 4.6) or insufficient oral hygiene (adjusted odds = 2.3) are risks for colonization by yeast, in general. The colonization with non-C. albicans species and co-colonization were not independently associated with any of the analyzed host-related factors. In particular, neither wearing a removable denture nor being elderly were significant predictors. © 2012 by the American College of Prosthodontists.

  9. Candida albicans Isolates from the Gut of Critically Ill Patients Respond to Phosphate Limitation by Expressing Filaments and a Lethal Phenotype

    PubMed Central

    Valuckaite, Vesta; Rolfes, Ronda J.; Babrowski, Trissa; Bethel, Cindy; Olivas, Andrea; Zaborina, Olga; Alverdy, John C.

    2012-01-01

    Candida albicans is an opportunistic pathogen that proliferates in the intestinal tract of critically ill patients where it continues to be a major cause of infectious-related mortality. The precise cues that shift intestinal C. albicans from its ubiquitous indolent colonizing yeast form to an invasive and lethal filamentous form remain unknown. We have previously shown that severe phosphate depletion develops in the intestinal tract during extreme physiologic stress and plays a major role in shifting intestinal Pseudomonas aeruginosa to express a lethal phenotype via conserved phosphosensory-phosphoregulatory systems. Here we studied whether phosphate dependent virulence expression could be similarly demonstrated for C. albicans. C. albicans isolates from the stool of critically ill patients and laboratory prototype strains (SC5314, BWP17, SN152) were evaluated for morphotype transformation and lethality against C. elegans and mice during exposure to phosphate limitation. Isolates ICU1 and ICU12 were able to filament and kill C. elegans in a phosphate dependent manner. In a mouse model of intestinal phosphate depletion (30% hepatectomy), direct intestinal inoculation of C. albicans caused mortality that was prevented by oral phosphate supplementation. Prototype strains displayed limited responses to phosphate limitation; however, the pho4Δ mutant displayed extensive filamentation during low phosphate conditions compared to its isogenic parent strain SN152, suggesting that mutation in the transcriptional factor Pho4p may sensitize C. albicans to phosphate limitation. Extensive filamentation was also observed in strain ICU12 suggesting that this strain is also sensitized to phosphate limitation. Analysis of the sequence of PHO4 in strain ICU12, its transcriptional response to phosphate limitation, and phosphatase assays confirmed that ICU12 demonstrates a profound response to phosphate limitation. The emergence of strains of C. albicans with marked responsiveness

  10. Genetic-relatedness of peri-implants and buccal Candida albicans isolates determined by RAPD-PCR.

    PubMed

    Bertone, Adriana M; Rosa, Alcira C; Nastri, Natalia; Santillán, Hector D; Ariza, Yamila; Iovannitti, Cristina A; Jewtuchowicz, Virginia M

    2016-12-01

    Molecular techniques have been used in recent studies to identify a wide range of potential bacterial pathogens in periimplant pockets of the oral cavity. However, the prevalence and molecular epidemiology of yeasts and species distribution related to periimplantitis are as yet unknown. The aim of this study was to determine the prevalence and distribution of yeasts in periimplant biofilm and to study genetic relatedness of Candida albicans. Yeasts recovered from periimplant biofilm samples (n=89) and buccal samples (n=120) were studied in 40 immunocompetent nonsmoking patients who visited the dental clinic of the Asociación Implantodontológica Argentina, Buenos Aires, Argentina, and had received oral rehabilitation with implants for more than five years. Yeasts recovered from samples were studied by typing assays using RAPDPCR. The prevalence of yeasts in the periimplant sulcus was 73% (n=29). C. albicans was the most prevalent species identified in this study population. The RAPD analysis showed identical genotypes in most C. albicans spp. from the two different sampling sites: buccal and periimplant. These findings suggest that periimplant biofilm is an ecological niche that favors the growth of yeast species. Most C. albicans found in periimplant biofilm originate from the endogenous infection caused by commensal strains.

  11. Mucins suppress virulence traits of Candida albicans.

    PubMed

    Kavanaugh, Nicole L; Zhang, Angela Q; Nobile, Clarissa J; Johnson, Alexander D; Ribbeck, Katharina

    2014-11-11

    Candida albicans is the most prevalent fungal pathogen of humans, causing a variety of diseases ranging from superficial mucosal infections to deep-seated systemic invasions. Mucus, the gel that coats all wet epithelial surfaces, accommodates C. albicans as part of the normal microbiota, where C. albicans resides asymptomatically in healthy humans. Through a series of in vitro experiments combined with gene expression analysis, we show that mucin biopolymers, the main gel-forming constituents of mucus, induce a new oval-shaped morphology in C. albicans in which a range of genes related to adhesion, filamentation, and biofilm formation are downregulated. We also show that corresponding traits are suppressed, rendering C. albicans impaired in forming biofilms on a range of different synthetic surfaces and human epithelial cells. Our data suggest that mucins can manipulate C. albicans physiology, and we hypothesize that they are key environmental signals for retaining C. albicans in the host-compatible, commensal state. The yeast Candida albicans causes both superficial infections of the mucosa and life-threatening infections upon entering the bloodstream. However, C. albicans is not always harmful and can exist as part of the normal microbiota without causing disease. Internal body surfaces that are susceptible to infection by C. albicans are coated with mucus, which we hypothesize plays an important role in preventing infections. Here, we show that the main components of mucus, mucin glycoproteins, suppress virulence attributes of C. albicans at the levels of gene expression and the corresponding morphological traits. Specifically, mucins suppress attachment to plastic surfaces and human cells, the transition to cell-penetrating hyphae, and the formation of biofilms (drug-resistant microbial communities). Additionally, exposure to mucins induces an elongated morphology that physically resembles the mating-competent opaque state but is phenotypically distinct. We

  12. [Malignant otitis externa caused by Candida albicans].

    PubMed

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

    2016-01-01

    Malignant otitis externa is also referred to as skull base osteomyelitis. Pseudomonas aeruginosa is the most common offending pathogen. However, fungal origin is not uncommon. 80-year-old patient having persistent left earache since two months despite adequate treatment. Otologic examination showed signs of inflammation in the auricular pavilion, ear canal stenosis with granulomas and purulent otorrhea. CT scan showed a filled otomastoid, extensive inflammatory process affecting the pre-auricular and retro-auricular tissues and lysis of the tympanic bulla. Given the lack of improvement, mycological examination was performed which revealed the presence of Candida Albicans. Cases of malignant otitis externa caused by Candida albicans are rarely reported. Fungal origin should be suspected in patients who have negative bacteriological samples and no improvement despite adequate antibiotic treatment. It should be confirmed by sometimes multiple mycological samples. Malignant otitis externa caused by Candida albicans is a rare potentially mortal infection.

  13. Antifungal activity and influence of propolis against germ tube formation as a critical virulence attribute by clinical isolates of Candida albicans.

    PubMed

    Haghdoost, N S; Salehi, T Z; Khosravi, A; Sharifzadeh, A

    2016-12-01

    The potentiality to switch between yeast and hyphal morphologies plays an important role in the virulence of Candida albicans (C. albicans). The objective of the present study was to evaluate the chemical composition, antifungal activity and influence of propolis upon germ tube formation of C. albicans clinical isolates. The major compounds of propolis ethanolic extract (PEE) was revealed by gas chromatography-mass spectrometry (GC/MS) analysis. Broth microdilution method was used for determination of minimal inhibitory concentration (MIC) and minimal fungicidal concentration (MFC) of this extract. C. albicans isolates were exposed to sub-MIC concentrations of propolis and germ tube reduction percent (GRP) and morphological transition from yeast to filamentous form were monitored microscopically. Phenolic compounds, aromatic acids, aliphatic acids, sugars and polycyclic aromatic hydrocarbons were the major compound classes in PEE. Mean of MIC and MFC values of PEE against C. albicans isolates were 360.6μg·mL(-1) and 1250.1μg·mL(-1), respectively. The increase in concentration led to a significant reduction in germ tube formation, so mean of GRP was 36.7±11.1 and 22±10.1 at concentration of ½ MIC and ¼ MIC of PEE, respectively. In conclusion, the present study indicated that PEE has interesting potential as a therapeutic agent that targets germ tube formation by C. albicans as a critical virulence factor. Copyright © 2016. Published by Elsevier Masson SAS.

  14. The European Confederation of Medical Mycology (ECMM) survey of candidaemia in Italy: in vitro susceptibility of 375 Candida albicans isolates and biofilm production.

    PubMed

    Tortorano, Anna Maria; Prigitano, Anna; Biraghi, Emanuela; Viviani, Maria Anna

    2005-10-01

    To investigate the in vitro antifungal susceptibility pattern of 375 Candida albicans bloodstream isolates recovered during the European Confederation of Medical Mycology survey of candidaemia performed in Lombardia, Italy and to test the ability to form biofilm. In vitro susceptibility to flucytosine, fluconazole, itraconazole, posaconazole, voriconazole and caspofungin was performed by broth microdilution following the NCCLS guidelines. Biofilm production was measured using the XTT reduction assay in 59 isolates selected as representative of different patterns of susceptibility to flucytosine and azoles. MICs (mg/L) at which 90% of the strains were inhibited were < or =0.25 for flucytosine, 0.25 for caspofungin, 4 for fluconazole and 0.06 for itraconazole, voriconazole and posaconazole. Flucytosine resistance was detected in five isolates and was associated with serotype B in 2/29 and serotype A in 3/346. Resistance to fluconazole was detected in 10 isolates; nine of these exhibited reduced susceptibility to the other azoles. Among the 10 patients with fluconazole-resistant C. albicans bloodstream infection, only one, an AIDS patient, had been previously treated with fluconazole. Biofilm production was observed in 23 isolates (39%) and was significantly associated with serotype B. No relationship was detected with the pattern of antifungal susceptibility. Resistance is uncommon in C. albicans isolates recovered from blood cultures, while biofilm production is a relatively frequent event. Periodic surveillance is warranted to monitor the incidence of in vitro antifungal resistance as well as of biofilm production.

  15. 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

  16. 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

  17. 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.

  18. 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.

  19. Virulence factors and genetic variability of vaginal Candida albicans isolates from HIV-infected women in the post-highly active antiretroviral era.

    PubMed

    Zanni, Pâmela Cristina Mastellaro Delvas; Bonfim-Mendonça, Patrícia de Souza; Negri, Melyssa; Nakamura, Sandra Sayuri; Donatti, Lucélia; Svidzinski, Terezinha Inez Estivalet; Consolaro, Márcia Edilaine Lopes

    2017-01-01

    Vulvovaginal candidiasis (VVC) in HIV-infected (HIV+) women is a serious public health problem. However, little is known about the virulence mechanisms of vaginal Candida albicans from HIV+ women in the post-highly active antiretroviral therapy (HAART) era. Here, we report a comparative analysis of the expression of key virulence factors and genetic variability of 26 vaginal C. albicans strains isolated from HIV+ women undergoing HAART and 18 from HIV-uninfected (HIV-) women. In general, we observed that C. albicans from HIV+ women receiving HAART showed lower expression of virulence factors compared with C. albicans from HIV- women, except for the proteinase activity which is highly expressed. The results in HIV-women further suggest that virulence factors appear to be expressed in response to the yeast stress, in the presence of an adequate immune response. Furthermore, the RAPD results showed a high heterogeneity among isolates from both groups of women. These findings in HIV+ women using HAART will help to improve the monitoring of vaginal yeast infections and the quality of life of patients.

  20. Synergistic effects of honey and propolis toward drug multi-resistant Staphylococcus aureus, Escherichia coli and Candida albicans isolates in single and polymicrobial cultures.

    PubMed

    Al-Waili, Noori; Al-Ghamdi, Ahmad; Ansari, Mohammad Javed; Al-Attal, Y; Salom, Khelod

    2012-01-01

    Propolis and honey are natural bee products with wide range of biological and medicinal properties. The study investigated antimicrobial activity of ethyl alcohol extraction of propolis collected from Saudi Arabia (EEPS) and from Egypt (EEPE), and their synergistic effect when used with honey. Single and polymicrobial cultures of antibiotic resistant human pathogens were tested. Staphylococcus aureus (S. aureus),), Escherichia coli (E. coli) and Candida albicans (C.albicans) were cultured in 10-100% (v/v) honey diluted in broth, or 0.08-1.0% (weight/volume) EEPS and EEPE diluted in broth. Four types of polymicrobial cultures were prepared by culturing the isolates with each other in broth (control) and broth containing various concentrations of honey or propolis. Microbial growth was assessed on solid plate media after 24 h incubation. EEPS and EEPE inhibited antibiotic resistant E.coli, and S.aureus, and C.albicans in single and polymicrobial cultures. S.aureus became more susceptible when it was cultured with E.coli or C.albicans or when all cultured together. C.albicans became more susceptible when it was cultured with S.aureus or with E.coli and S. aureus together. The presence of ethyl alcohol or honey potentiated antimicrobial effect of propolis toward entire microbes tested in single or polymicrobial cultures. EEPS had lower MIC toward E.coli and C.albicans than EEPE. When propolis was mixed with honey, EEPS showed lower MIC than EEPE. In addition, honey showed lower MIC toward entire microbes when mixed with EEPS than when it was mixed with EEPE. 1) propolis prevents the growth of the microorganisms in single and mixed microbial cultures, and has synergistic effect when used with honey or ethyl alcohol, 2) the antimicrobial property of propolis varies with geographical origin, and 3) this study will pave the way to isolate active ingredients from honey and propolis to be further tested individually or in combination against human resistant infections.

  1. Isolation and Purification of a Novel Deca-Antifungal Peptide from Potato (Solanum tuberosum L. cv. Jopung) Against Candida albicans

    PubMed Central

    Lee, Jong-Kook; Gopal, Ramamourthy; Seo, Chang Ho; Cheong, Hyeonsook; Park, Yoonkyung

    2012-01-01

    In a previous study, an antifungal protein, AFP-J, was purified from tubers of the potato (Solanum tuberosum cv. L Jopung) and by gel filtration and HPLC. In this study, the functional peptide was characterized by partial acid digestion using HCl and HPLC. We obtained three peaks from the AFP-J, the first and third peaks were not active in the tested fungal strain. However, the second peak, which was named Potide-J, was active (MIC; 6.25 μg/mL) against Candida albicans. The amino acid sequences were analyzed by automated Edman degradation, and the amino acid sequence of Potide-J was determined to be Ala-Val-Cys-Glu-Asn-Asp-Leu-Asn-Cys-Cys. Mass spectrometry showed that its molecular mass was 1083.1 Da. Finally, we confirmed that a disulfide bond was present between Cys3 and Cys9 or Cys10. Using this structure, Potide-J was synthesized via solid-phase methods. In these experiments, only the linear sequence was shown to display strong activity against Candida albicans. These results suggest that Potide-J may be an excellent candidate compound for the development of commercially applicable antibiotic agents. PMID:22605963

  2. Isolation and purification of a novel deca-antifungal peptide from potato (Solanum tuberosum L. cv. Jopung) against Candida albicans.

    PubMed

    Lee, Jong-Kook; Gopal, Ramamourthy; Seo, Chang Ho; Cheong, Hyeonsook; Park, Yoonkyung

    2012-01-01

    In a previous study, an antifungal protein, AFP-J, was purified from tubers of the potato (Solanum tuberosum cv. L Jopung) and by gel filtration and HPLC. In this study, the functional peptide was characterized by partial acid digestion using HCl and HPLC. We obtained three peaks from the AFP-J, the first and third peaks were not active in the tested fungal strain. However, the second peak, which was named Potide-J, was active (MIC; 6.25 μg/mL) against Candida albicans. The amino acid sequences were analyzed by automated Edman degradation, and the amino acid sequence of Potide-J was determined to be Ala-Val-Cys-Glu-Asn-Asp-Leu-Asn-Cys-Cys. Mass spectrometry showed that its molecular mass was 1083.1 Da. Finally, we confirmed that a disulfide bond was present between Cys(3) and Cys(9) or Cys(10). Using this structure, Potide-J was synthesized via solid-phase methods. In these experiments, only the linear sequence was shown to display strong activity against Candida albicans. These results suggest that Potide-J may be an excellent candidate compound for the development of commercially applicable antibiotic agents.

  3. Rapid characterisation of Candida albicans by pyrolysis mass spectrometry.

    PubMed

    White, G C; Sisson, P R; Freeman, R; Cookson, B D

    1994-08-01

    Clinical isolates (41) of Candida spp. from three possible outbreaks of nosocomially-acquired infection were compared by pyrolysis mass spectrometry (PMS) and by a combined morphotyping and resistotyping (M-R typing) method. Both systems characterised all the isolates and distinguished one isolate of C. tropicalis and another of C. glabrata from the 39 isolates of C. albicans. Results from both systems suggested that cross-infection with a single strain contributed to two of the outbreaks. In several instances, more than one strain of C. albicans was found amongst multiple isolates from the same patient. PMS is a simple, rapid and objective technique capable of characterising C. albicans isolates; discrimination was similar to M-R typing.

  4. Isolation and characterization of Candida albicans morphological mutants derepressed for the formation of filamentous hypha-type structures

    SciTech Connect

    Gil, C.; Pomes, R.; Nombela, C. )

    1990-05-01

    Several Candida albicans morphological mutants were obtained by a procedure based on a combined treatment with nitrous acid plus UV irradiation and a double-enrichment step to increase the proportion of mutants growing as long filamentous structures. Altered cell morphogenesis in these mutants correlated with an altered colonial phenotype. Two of these mutants, C. albicans NEL102 and NEL103, were selected and characterized. Mutant blastoconidia initiated budding but eventually gave rise to filamentous hypha-type formations. These filaments were long and septate, and they branched very regularly at positions near septa. Calcofluor white (which is known to bind chitin-rich areas) stained septa, branching zones, and filament tips very intensely, as observed under the fluorescence microscope. Wild-type hybrids were obtained by fusing protoplasts of strain NEL102 with B14, another morphological mutant previously described as being permanently pseudomycelial, indicating that genetic determinants responsible for the two altered phenotypes are different. The mutants characterized in this work seemed to sequentially express the morphogenic characteristics of C. albicans, from blastoconidia to hyphae, in the absence of any inducer. Further characterization of these strains could be relevant to gain understanding of the genetic control of dimorphism in this species.

  5. Diallyl disulphide depletes glutathione in Candida albicans

    PubMed Central

    Lemar, Katey M.; Aon, Miguel A.; Cortassa, Sonia; O’Rourke, Brian; T. Müller, Carsten; Lloyd, David

    2008-01-01

    Using two-photon scanning laser microscopy, we investigated the effect of an Allium sativum (garlic) constituent, diallyl disulphide (DADS), on key physiological functions of the opportunistic pathogen Candida albicans. A short 30 min exposure to 0.5 mm DADS followed by removal induced 70% cell death (50% necrotic, 20% apoptotic) within 2 h, increasing to 75% after 4 h. The early intracellular events associated with DADS-induced cell death were monitored with two-photon fluorescence microscopy to track mitochondrial membrane potential (ΔΨm), reactive oxygen species (ROS) and NADH or reduced glutathione (GSH) under aerobic conditions. DADS treatment decreased intracellular GSH and elevated intracellular ROS levels. Additionally, DADS induced a marked decrease of ΔΨm and lowered respiration in cell suspensions and isolated mitochondria. In vitro kinetic experiments in cell-free extracts suggest that glutathione-S-transferase (GST) is one of the intracellular targets of DADS. Additional targets were also identified, including inhibition of a site or sites between complexes II-IV in the electron transport chain, as well as the mitochondrial ATP-synthase. The results indicate that DADS is an effective antifungal agent able to trigger cell death in Candida, most probably by eliciting oxidative stress as a consequence of thiol depletion and impaired mitochondrial function. PMID:17534841

  6. 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.

  7. [Proteinase activity in Candida albicans strains isolated from the oral cavity of immunocompromised patients, with oral candidiasis and in healthy subjects].

    PubMed

    Hernández-Solís, Sandra E; Rueda-Gordillo, Florencio; Rojas-Herrera, Rafael A

    2014-01-01

    Candida albicans has a variety of virulence factors, including secreted aspartyl proteases, which are determinant factors in the pathogenesis of this yeast in immunocompromised patients. Proteinase activity was identified in C. albicans strains isolated from the oral cavity of immunocompromised patients with cancer, diabetes and HIV+, with oral candidiasis and in healthy subjects. Two hundred and fifty C. albicans strains were analyzed, distributed in 5 different groups: patients with cancer, diabetes, HIV+, with oral candidiasis and healthy subjects. Proteolytic activity was identified in 46% of the strains from cancer patients, 54% from HIV+ patients, 60% from diabetics, 70% from oral candidiasis patients, and 42% from healthy subjects. Activity was higher in strains from immunocompromised and oral candidiasis patients than in healthy subjects. Differences were observed between the candidiasis-healthy, candidiasis-HIV+, and diabetic-healthy groups. No differences were observed between the oral candidiasis, diabetes and cancer patients, between the diabetes and HIV+ patients, or between the cancer patients, HIV+ patients and healthy subjects. The present results suggest that although secreted aspartyl proteases are important in the pathogenesis of C. albicans, their activity depends on host conditions. Copyright © 2012 Revista Iberoamericana de Micología. Published by Elsevier Espana. All rights reserved.

  8. Comparison of the hemolytic activity between C. albicans and non-albicans Candida species.

    PubMed

    Rossoni, Rodnei Dennis; Barbosa, Júnia Oliveira; Vilela, Simone Furgeri Godinho; Jorge, Antonio Olavo Cardoso; Junqueira, Juliana Campos

    2013-01-01

    The ability to produce enzymes, such as hemolysins, is an important virulence factor for the genus Candida.The objective of this study was to compare the hemolytic activity between C. albicansand non-albicans Candida species. Fifty strains of Candida species, isolated from the oral cavity of patients infected with HIV were studied. The isolates included the following species: C. albicans, C. dubliniensis, C. glabrata, C. tropicalis, C. krusei, C. parapsilosis, C. dubliniensis, C. norvegensis, C. lusitaniae, and C. guilliermondii. Hemolysin production was evaluated on Sabouraud dextrose agar containing chloramphenicol, blood, and glucose. A loop-full of pure Candidaculture was spot-inoculated onto plates and incubated at 37 ºC for 24 h in a 5% CO2 atmosphere. Hemolytic activity was defined as the formation of a translucent halo around the colonies. All C. albicansstrains that were studied produced hemolysins. Among the non-albicans Candidaspecies, 86% exhibited hemolytic activity. Only C. guilliermondiiand some C. parapsilosis isolates were negative for this enzyme. In conclusion, most non-albicans Candidaspecies had a similar ability to produce hemolysins when compared to C. albicans.

  9. Collaborative Consensus for Optimized Multilocus Sequence Typing of Candida albicans

    PubMed Central

    Bougnoux, M.-E.; Tavanti, A.; Bouchier, C.; Gow, N. A. R.; Magnier, A.; Davidson, A. D.; Maiden, M. C. J.; d'Enfert, C.; Odds, F. C.

    2003-01-01

    A panel of 86 different Candida albicans isolates was subjected to multilocus sequence typing (MLST) in two laboratories to obtain sequence data for 10 published housekeeping gene fragments. Analysis of data for all possible combinations of five, six, seven, eight, and nine of the fragments showed that a set comprising the fragments AAT1a, ACC1, ADP1, MPIb, SYA1, VPS13, and ZWF1b was the smallest that yielded 86 unique diploid sequence types for the 86 isolates. This set is recommended for future MLST with C. albicans. PMID:14605179

  10. Mucosal biofilms of Candida albicans.

    PubMed

    Ganguly, Shantanu; Mitchell, Aaron P

    2011-08-01

    Biofilms are microbial communities that form on surfaces and are embedded in an extracellular matrix. C. albicans forms pathogenic mucosal biofilms that are evoked by changes in host immunity or mucosal ecology. Mucosal surfaces are inhabited by many microbial species; hence these biofilms are polymicrobial. Several recent studies have applied paradigms of biofilm analysis to study mucosal C. albicans infections. These studies reveal that the Bcr1 transcription factor is a master regulator of C. albicans biofilm formation under diverse conditions, though the most relevant Bcr1 target genes can vary with the biofilm niche. An important determinant of mucosal biofilm formation is the interaction with host defenses. Finally, studies of interactions between bacterial species and C. albicans provide insight into the communication mechanisms that endow polymicrobial biofilms with unique properties.

  11. Candida albicans: genotyping methods and clade related phenotypic characteristics

    PubMed Central

    Lyon, Juliana P.; Moraes, Karen C.M.; Moreira, Leonardo M.; Aimbire, Flávio; de Resende, Maria Aparecida

    2010-01-01

    Several molecular methods, such as Southern blotting hybridization, Multilocus Sequence Typing, and DNA microsatellite analysis, have been employed to genotype Candida albicans. The genotype analysis allows to group strains in clades, that is, a group composed of one ancestor and its descendants. These genotype studies demonstrate that clades distribution is influenced by geographic area as well as that antifungal resistance is associated with particular clades. These findings suggested that C. albicans reproduces mainly in a clonal manner, with certain degree of DNA microevolution. Additionally, virulence factors and site of isolation have also been associated with clade specificity. The present article is a brief review about the methods used for Candida genotyping and the correlated clade systems established. Special emphasis is given to Ca3 hybridization, MLST, and Microsatellites. The present work is also focused on the phenotypic and physiological traits associated with Candida clades. PMID:24031564

  12. Chemical composition and antifungal activity of Satureja hortensis L. essentiall oil against planktonic and biofilm growth of Candida albicans isolates from buccal lesions of HIV(+) individuals.

    PubMed

    Sharifzadeh, Aghil; Khosravi, Ali Reza; Ahmadian, Shahin

    2016-07-01

    Oral candidiasis is an opportunistic infection of the oral cavity which usually occurs in the immunocompromised individuals. Candida albicans (C. albicans) is the most common species of yeast responsible for oral candidiasis. This study investigated the effects of Satureja hortensis L. essentiall oil (EO) on the planktonic, biofilm formation and mature biofilms of C. albicans isolates from buccal lesions of HIV(+) individuals. MTT reduction assay, broth micro-dilution method and scanning electron microscopy (SEM) were employed to determine the effect of mentioned EO on the C. albicans planktonic and biofilm forms. GC-GC/MS was used to detect the major active compounds of EO. Thymol (45.9%), gamma-terpinen (16.71%), carvacrol (12.81%) and p-cymene (9.61%) were found as the most abundant constituents. MIC values ranged from 250 to 400 μg/ml and MFC values ranged from 350 to 500 μg/ml. All C. albicans isolates formed biofilm on polystyrene plats but the quantity of biofilm mass (optical density) was different for the isolates ranging from 0.850 to 0.559 nm. The mean of biofilm formation by C. albicans isolates was reduced by 87.1 ± 3.7%, 73.6 ± 5.1%, 69.4 ± 5.3% and 67 ± 4.2% at 4800, 3200, 2400 and 1600 μg/ml, respectively. In sub-MIC concentration, SEM analysis revealed loosening of cells, deformity of three dimensional structures of biofilms and shrinkage in cell membranes of sessile cells. In conclusion, the substantial anti-fungal activity showed by S. hortensis L. EO suggests exploitation of this oil as potential natural anti-biofilm product to deal with the problem of buccal cavity lesion associated with C. albicans. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Comparison of Antimicrobial Activity of Chlorhexidine, Coconut Oil, Probiotics, and Ketoconazole on Candida albicans Isolated in Children with Early Childhood Caries: An In Vitro Study.

    PubMed

    Shino, Beena; Peedikayil, Faizal C; Jaiprakash, Shyamala R; Ahmed Bijapur, Gufran; Kottayi, Soni; Jose, Deepak

    2016-01-01

    Background. Early childhood caries (ECC) is associated with early colonisation and high levels of cariogenic microorganisms. With C. albicans being one of those, there is a need to determine the effectiveness of various chemotherapeutic agents against it. The study is aimed at isolating Candida species in children with ECC and at studying the antifungal effect of coconut oil, probiotics, Lactobacillus, and 0.2% chlorhexidine on C. albicans in comparison with ketoconazole. Materials and Methods. Samples were collected using sterile cotton swabs, swabbed on the tooth surfaces from children with ECC of 3 to 6 yrs and streaked on Sabouraud dextrose agar (HI Media) plates and incubated in a 5% CO2 enriched atmosphere at 37°C for 24 hours. Candida was isolated and its susceptibility to probiotics, chlorhexidine, ketoconazole, and coconut oil was determined using Disc Diffusion method. Results. The mean zone of inhibition for chlorhexidine was 21.8 mm, whereas for coconut oil it was 16.8 mm, for probiotics it was 13.5 mm, and for ketoconazole it was 22.3 mm. The difference between the groups was not statistically significant (Chi-square value 7.42, P value 0.06). Conclusion. Chlorhexidine and coconut oil have shown significant antifungal activity which is comparable with ketoconazole.

  14. Comparison of Antimicrobial Activity of Chlorhexidine, Coconut Oil, Probiotics, and Ketoconazole on Candida albicans Isolated in Children with Early Childhood Caries: An In Vitro Study

    PubMed Central

    Ahmed Bijapur, Gufran; Kottayi, Soni; Jose, Deepak

    2016-01-01

    Background. Early childhood caries (ECC) is associated with early colonisation and high levels of cariogenic microorganisms. With C. albicans being one of those, there is a need to determine the effectiveness of various chemotherapeutic agents against it. The study is aimed at isolating Candida species in children with ECC and at studying the antifungal effect of coconut oil, probiotics, Lactobacillus, and 0.2% chlorhexidine on C. albicans in comparison with ketoconazole. Materials and Methods. Samples were collected using sterile cotton swabs, swabbed on the tooth surfaces from children with ECC of 3 to 6 yrs and streaked on Sabouraud dextrose agar (HI Media) plates and incubated in a 5% CO2 enriched atmosphere at 37°C for 24 hours. Candida was isolated and its susceptibility to probiotics, chlorhexidine, ketoconazole, and coconut oil was determined using Disc Diffusion method. Results. The mean zone of inhibition for chlorhexidine was 21.8 mm, whereas for coconut oil it was 16.8 mm, for probiotics it was 13.5 mm, and for ketoconazole it was 22.3 mm. The difference between the groups was not statistically significant (Chi-square value 7.42, P value 0.06). Conclusion. Chlorhexidine and coconut oil have shown significant antifungal activity which is comparable with ketoconazole. PMID:27051559

  15. Rapid detection of ERG11 gene mutations in clinical Candida albicans isolates with reduced susceptibility to fluconazole by rolling circle amplification and DNA sequencing.

    PubMed

    Wang, Huiping; Kong, Fanrong; Sorrell, Tania C; Wang, Bin; McNicholas, Paul; Pantarat, Namfon; Ellis, David; Xiao, Meng; Widmer, Fred; Chen, Sharon Ca

    2009-08-14

    Amino acid substitutions in the target enzyme Erg11p of azole antifungals contribute to clinically-relevant azole resistance in Candida albicans. A simple molecular method for rapid detection of ERG11 gene mutations would be an advantage as a screening tool to identify potentially-resistant strains and to track their movement. To complement DNA sequencing, we developed a padlock probe and rolling circle amplification (RCA)-based method to detect a series of mutations in the C. albicans ERG11 gene using "reference" azole-resistant isolates with known mutations. The method was then used to estimate the frequency of ERG11 mutations and their type in 25 Australian clinical C. albicans isolates with reduced susceptibility to fluconazole and in 23 fluconazole-susceptible isolates. RCA results were compared DNA sequencing. The RCA assay correctly identified all ERG11 mutations in eight "reference" C. albicans isolates. When applied to 48 test strains, the RCA method showed 100% agreement with DNA sequencing where an ERG11 mutation-specific probe was used. Of 20 different missense mutations detected by sequencing in 24 of 25 (96%) isolates with reduced fluconazole susceptibility, 16 were detected by RCA. Five missense mutations were detected by both methods in 18 of 23 (78%) fluconazole-susceptible strains. DNA sequencing revealed that mutations in non-susceptible isolates were all due to homozygous nucleotide changes. With the exception of the mutations leading to amino acid substitution E266D, those in fluconazole-susceptible strains were heterozygous. Amino acid substitutions common to both sets of isolates were D116E, E266D, K128T, V437I and V488I. Substitutions unique to isolates with reduced fluconazole susceptibility were G464 S (n = 4 isolates), G448E (n = 3), G307S (n = 3), K143R (n = 3) and Y123H, S405F and R467K (each n = 1). DNA sequencing revealed a novel substitution, G450V, in one isolate. The sensitive RCA assay described here is a simple, robust and rapid

  16. Pathogenicity and virulence of Candida dubliniensis: comparison with C. albicans.

    PubMed

    Vilela, M M S; Kamei, K; Sano, A; Tanaka, R; Uno, J; Takahashi, I; Ito, J; Yarita, K; Miyaji, M

    2002-06-01

    Candida dubliniensis is a newly described fungus that is frequently isolated from the oral cavities of HIV-positive patients. Although extensive studies have been performed on the phylogeny of C. dubliniensis, little is known about the pathogenic ecology of this yeast. Here we examined aspects related to C. dubliniensis in comparison with those of C. albicans. When injected intravenously into mice, C. dubliniensis had a higher survival rate than C. albicans. Histopathological analysis disclosed that C. dubliniensis remained mostly in the yeast form in the infected organs, whereas C. albicans changed into the mycelial form. The host inflammatory reaction was aggressive with C. dubliniensis infection and mild with C. albicans infection. Co-culture of the yeasts with human polymorphonuclear leukocytes disclosed that C. dubliniensis is more vulnerable to the fungicidal activity of leukocytes than C. albicans. C. dubliniensis was also more susceptible to the toxic effect of hydrogen peroxide. When cultured in vitro, C. dubliniensis grew more slowly than C. albicans, but the formation of germ tubes was faster. When the fungi were cultured in RPMI 1640, a fetal bovine serum supplement suppressed the growth of C. dubliniensis but enhanced that of C. albicans. These results clearly indicated that C. dubliniensis is less virulence than C. albicans.

  17. Gymnemic Acids Inhibit Hyphal Growth and Virulence in Candida albicans

    PubMed Central

    Vediyappan, Govindsamy; Dumontet, Vincent; Pelissier, Franck; d’Enfert, Christophe

    2013-01-01

    Candida albicans is an opportunistic and polymorphic fungal pathogen that causes mucosal, disseminated and invasive infections in humans. Transition from the yeast form to the hyphal form is one of the key virulence factors in C. albicans contributing to macrophage evasion, tissue invasion and biofilm formation. Nontoxic small molecules that inhibit C. albicans yeast-to-hypha conversion and hyphal growth could represent a valuable source for understanding pathogenic fungal morphogenesis, identifying drug targets and serving as templates for the development of novel antifungal agents. Here, we have identified the triterpenoid saponin family of gymnemic acids (GAs) as inhibitor of C. albicans morphogenesis. GAs were isolated and purified from Gymnema sylvestre leaves, the Ayurvedic traditional medicinal plant used to treat diabetes. Purified GAs had no effect on the growth and viability of C. albicans yeast cells but inhibited its yeast-to-hypha conversion under several hypha-inducing conditions, including the presence of serum. Moreover, GAs promoted the conversion of C. albicans hyphae into yeast cells under hypha inducing conditions. They also inhibited conidial germination and hyphal growth of Aspergillus sp. Finally, GAs inhibited the formation of invasive hyphae from C. albicans-infected Caenorhabditis elegans worms and rescued them from killing by C. albicans. Hence, GAs could be useful for various antifungal applications due to their traditional use in herbal medicine. PMID:24040201

  18. Gymnemic acids inhibit hyphal growth and virulence in Candida albicans.

    PubMed

    Vediyappan, Govindsamy; Dumontet, Vincent; Pelissier, Franck; d'Enfert, Christophe

    2013-01-01

    Candida albicans is an opportunistic and polymorphic fungal pathogen that causes mucosal, disseminated and invasive infections in humans. Transition from the yeast form to the hyphal form is one of the key virulence factors in C. albicans contributing to macrophage evasion, tissue invasion and biofilm formation. Nontoxic small molecules that inhibit C. albicans yeast-to-hypha conversion and hyphal growth could represent a valuable source for understanding pathogenic fungal morphogenesis, identifying drug targets and serving as templates for the development of novel antifungal agents. Here, we have identified the triterpenoid saponin family of gymnemic acids (GAs) as inhibitor of C. albicans morphogenesis. GAs were isolated and purified from Gymnema sylvestre leaves, the Ayurvedic traditional medicinal plant used to treat diabetes. Purified GAs had no effect on the growth and viability of C. albicans yeast cells but inhibited its yeast-to-hypha conversion under several hypha-inducing conditions, including the presence of serum. Moreover, GAs promoted the conversion of C. albicans hyphae into yeast cells under hypha inducing conditions. They also inhibited conidial germination and hyphal growth of Aspergillus sp. Finally, GAs inhibited the formation of invasive hyphae from C. albicans-infected Caenorhabditis elegans worms and rescued them from killing by C. albicans. Hence, GAs could be useful for various antifungal applications due to their traditional use in herbal medicine.

  19. Ectophosphatase activity in Candida albicans influences fungal adhesion: study between HIV-positive and HIV-negative isolates.

    PubMed

    Portela, M B; Kneipp, L F; Ribeiro de Souza, I P; Holandino, C; Alviano, C S; Meyer-Fernandes, J R; de Araújo Soares, R M

    2010-07-01

    This study describes the expression of acidic ectophosphatase activity on twenty isolates of C. albicans from oral cavities of HIV-infected children (HIV+) and compares them with fifteen isolates from HIV-negative children (HIV-), as well as the fungal adhesion to epithelial cells and medical records. The activities were measured in intact cells grown in BHI medium for 48 h at 37 degrees C. Phosphatase activity was assayed at pH 5.5 using 4-methylumbelliferyl phosphate. Yeast adhesion was measured using the MA 104 epithelial cell line. Mean values of ectophosphatase activity were 610.27 +/- 166.36 and 241.25 +/- 78.96 picomoles 4-methylumbelliferone/h/10(7) cells for HIV+ and HIV- group, respectively (P = 0.049). No correlation between C. albicans enzyme activity from HIV children with viral load and CD4 percentual was observed. Yeasts with high enzyme activity, isolated from HIV+ children showed greater adherence than yeasts with basal levels of ectophosphatases from HIV- (Spearman correlation, r = 0.8). Surface phosphatase activity was apparently involved in the adhesion to host cells, as the enhanced attachment of C. albicans to host epithelial cells was reversed by pretreatment of yeast with sodium orthovanadate (1 mM), an acid phosphatase inhibitor. These results show that C. albicans from HIV+ has an ectophosphatase activity significantly higher than the other isolates. Yeasts expressing higher levels of surface phosphatase activity showed greater adhesion to epithelial cells. So, the activity of acidic surface phosphatases on these cells may contribute to the early mechanisms required for disease establishment.

  20. Murine model of concurrent oral and vaginal Candida albicans colonisation.

    PubMed

    Rahman, Durdana; Mistry, Mukesh; Thavaraj, Selvam; Naglik, Julian R; Challacombe, Stephen J

    2012-01-01

    Investigations into the complex interaction between the fungal pathogen Candida albicans and its human host require the use of animals as in vivo models. A major advance is the creation of a low-oestrogen murine model of concurrent oral and vaginal C. albicans colonisation that resembles human candidal carriage at both mucosal sites. Weekly intramuscular (5 μg) and subcutaneous (5 μg) oestrogen administration was determined as optimal, enhancing oral colonisation but essential for vaginal colonisation. Using a clinical C. albicans oral isolate, persistent colonisation for up to 6 weeks can be achieved at both sites in two strains of mice (BALB/c and C57BL/6). This concurrent model of mucosal colonisation reduces the numbers of experimental mice by half, and opens up new avenues of research in assessing potential mucosal vaccine candidates and in studying delicate host-pathogen interactions during the most natural state of C. albicans epithelial colonisation.

  1. Anti-candidal activity of essential oils alone and in combination with amphotericin B or fluconazole against multi-drug resistant isolates of Candida albicans.

    PubMed

    Khan, Mohd Sajjad Ahmad; Malik, Abida; Ahmad, Iqbal

    2012-01-01

    Therapy for candidiasis is becoming problematic due to the toxicities of currently available antifungal agents and the increasing prevalence of resistance among the etiologic agents. Therefore, new antifungals and alternative approaches are needed. In this study, 20 fluconazole-resistant strains of Candida albicans were found to have varying levels of resistance to other azoles, i.e., itraconazole (MIC of 4-128 μg/ml) and ketoconazole (2-256 μg/ml). In addition, 13 of these isolates appeared resistant to amphotericin B (32-128 μg/ml). A total of 21 plant essential oils were screened for their antifungal activity against these multi-drug resistant isolates. The oils of Cymbopogon martini, i.e., citral and cinnamaldehyde, exhibited strong inhibitory activity with minimum inhibitory concentrations (MIC(50)) ranging from 90-100 μg/ml. The test oils were more effective than fluconazole and amphotericin B in inhibiting azole- and amphotericin B-resistant, as well as amphotericin B-susceptible isolates. The test oils and especially eugenol, exhibited significant synergy with fluconazole or amphotericin B against the test isolates. These findings suggest the possible effective use of certain oils alone or in combination with fluconazole or amphotericin B, against multi-drug resistant isolates of C. albicans.

  2. Characterization of a novel antibiofilm effect of nitric oxide-releasing aspirin (NCX-4040) on Candida albicans isolates from denture stomatitis patients

    PubMed Central

    Madariaga-Venegas, Francisco; Fernández-Soto, Roberto; Duarte, Luisa Fernanda; Suarez, Nicole; Delgadillo, Daniela; Jara, José A.; Fernández-Ramires, Ricardo; Urzúa, Blanca; Molina-Berríos, Alfredo

    2017-01-01

    Candida albicans biofilms play a key role in denture stomatitis, one of the most common oral pathologies in elderly people. Because biofilms are highly resistant to antifungals, new pharmacological strategies are needed. Aspirin and nitric oxide-donor molecules have both shown antibiofilm effects on C. albicans, making them promising candidates for treatment. In this study, we evaluated the antifungal/antibiofilm effect of a nitric-oxide releasing aspirin (NO-ASA) on C. albicans isolates from denture stomatitis patients in vitro. Disk diffusion assays showed that while NO-ASA had no antifungal effect, the drug potentiated fluconazole inhibition zone diameters, increasing the effect of fluconazole by 20–30% (p<0.05). The effect of NO-ASA on the morphogenesis of C. albicans was evaluated using light microscopy after inducing hyphae formation. For all clinical strains assayed, 125 μM NO-ASA significantly decreased the number of filamentous cells present (p<0.01). Adhesion to abiotic surfaces, a critical event for biofilm formation, was evaluated in 96-well polystyrene plates using crystal violet assay; 125 μM NO-ASA significantly inhibited adhesion. Biofilms were observed with scanning electron microscopy (SEM) and quantified using XTT reduction assay. NO-ASA decreased biofilm formation (IC50 ranging from 300 μM to 700 μM), consistent with SEM findings of altered biofilm microarchitecture. PGE2 and carboxy-PTIO (an NO scavenger) both blocked the antibiofilm effects of NO-ASA, suggesting that the efficacy of NO-ASA may be associated with both inhibition of PGE2 synthesis and release of NO. NO-ASA is a promising novel antibiofilm agent for treating fluconazole-resistant strains of C. albicans. PMID:28493889

  3. Oral Candida albicans carriage in healthy preschool and school children.

    PubMed

    Rozkiewicz, D; Daniluk, T; Zaremba, M L; Cylwik-Rokicka, D; Stokowska, W; Pawińska, M; Dabrowska, E; Marczuk-Kolada, G; Waszkiel, D

    2006-01-01

    The purpose of the present study was to detect Candida albicans carriage in the oral cavity of healthy preschool and school children. The second aim was the determination of correlation between C. albicans occurrence and dental caries in children population. The samples for mycological examinations were collected from the pharynx and supragingival plaque, and carious lesions in 102 children, aged 4-7 years (preschool children) and 104 children and adolescents, aged 12 and 18 (school children). All samples were cultured directly on Sabouraud agar medium. Isolated yeasts were identified based on API 20C AUX (bioMérieux). A total of 123 C. albicans strains were isolated, in which 61 (49.6%) derived from supragingival plaque, 48 (39%)--from carious lesions, and 14 (11.4%)--from pharyngeal swabs. C. albicans was isolated from the samples of single material in 61 children (35--school children, 26 --preschool children) while from the rest of 29 children, C. albicans was isolated from two (25x) or three materials (4x). C. albicans was detected in 48/75 (64%) children with dental caries; the rate was statistically significantly higher as compared to the overall number of children with C. albicans carriage (90/206; 43.7%) (p = 0.0026). Similar results was obtained in preschool children (38/61; 62.3% and 47/102; 46.1%, respectively) (p = 0.0449), as in school children (10/14; 71.4% and 43/104; 41.3%, respectively) (p = 0.0336). 1) Candida albicans was observed in the oral cavity of healthy children with high (approximately 40%)--comparable rate in school and preschool children (p > 0.05). 2) C. albicans was isolated with high comparable rate from carious lesions in preschool and school children. The statistically significant differences between the rate of C. albicans in carious lesions in preschool children (62.3%) and school children (71.4%) and the overall number of children with C. albicans carriage in the oral cavity of children in both age groups (p < 0.05) were showed.

  4. 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

  5. Typing Candida albicans oral isolates from healthy brazilian schoolchildren using multilocus enzyme electrophoresis reveals two highly polymorphic taxa

    PubMed Central

    Boriollo, Marcelo Fabiano Gomes; Spolidorio, Denise Madalena Palomari; Barros, Letizia Monteiro; Bassi, Rodrigo Carlos; Garcia, José Antonio Dias; Costa, Ana Maria Duarte Dias; Rosa, Edvaldo Antonio Ribeiro; Höfling, José Francisco

    2011-01-01

    The genetic diversity of C. albicans oral isolates from 75 healthy schoolchildren from eight schools located in different geographic areas of Piracicaba city, São Paulo state, Brazil, was established using isoenzymes marker (Multilocus Enzyme Electrophoresis – MLEE) and cluster analysis. Patterns of monoclonal and polyclonal oral colonization by C. albicans within and between groups of schoolchildren were identified. However, significant divergence between the observed and the expected genotypic frequencies (Hardy-Weinberg equilibrium test) was not detected in the geographically adjacent groups, suggesting the hypothesis that populations of healthy schoolchildren do not correspond to the selection factor (differential survival) of strains. Two highly polymorphic and distantly genetically related taxa (A and B) were identified within the total population of yeasts, each contained subgroups (A1, A2, A3, A4, B1 and B2) and clusters of moderately related strains (from I to X), suggesting the existence of strains restricted or not to certain groups of geographically limited, healthy students. However, the coexistence of identical strains in healthy schoolchildren from the same school (geographically related) reinforces the hypothesis of oral transmission, where the sources of propagation could be explored. Furthermore, this could also be used in current and retrospective analyses of C. albicans isolated from immunocompetent and immunocompromised people, in order to detect commensal or potentially pathogenic yeast groups, predominantly in candidiasis, and in the development of strategies to prevent transmission or human propagation. PMID:24031720

  6. The in vitro and in vivo efficacy of fluconazole in combination with farnesol against Candida albicans isolates using a murine vulvovaginitis model.

    PubMed

    Bozó, Aliz; Domán, Marianna; Majoros, László; Kardos, Gábor; Varga, István; Kovács, Renátó

    2016-11-01

    Farnesol is a quorum-sensing molecule that inhibits biofilm formation in Candida albicans. Previous in vitro data suggest that, in combination with certain antifungals, farnesol may have an adjuvant anti-biofilm agent. However, the in vivo efficacy of farnesol is very questionable. Therefore, the in vitro and in vivo activity of fluconazole combined with farnesol was evaluated against C. albicans biofilms using fractional inhibitory concentration index (FICI) determination, time-kill experiments and a murine vulvovaginitis model. The median biofilm MICs of fluconazole-sensitive C. albicans isolates ranged between 4 -> 512 mg/L and 150-300 μM for fluconazole and farnesol, respectively. These values were 512 -> 512 mg/L and > 300 μM for fluconazole-resistant clinical isolates. Farnesol decreased the median MICs of fluconazole by 2-64-fold for biofilms. Based on FICI, synergistic interaction was observed only in the case of the sessile SC5314 reference strain (FICIs: 0.16-0.27). In time-kill studies, only the 512 mg/L fluconazole and 512 mg/L fluconazole + 75 μM farnesol reduced biofilm mass significantly at each time point in the case of all isolates. The combination reduced the metabolic activity of biofilms for all isolates in a concentration- and time-dependent manner. Our findings revealed that farnesol alone was not protective in a murine vulvovaginitis model. Farnesol was not beneficial in combination with fluconazole for fluconazole-susceptible isolates, but partially increased fluconazole activity against one fluconazole-resistant isolate, but not the other one.

  7. Early Adhesion of Candida albicans onto Dental Acrylic Surfaces.

    PubMed

    Aguayo, S; Marshall, H; Pratten, J; Bradshaw, D; Brown, J S; Porter, S R; Spratt, D; Bozec, L

    2017-07-01

    Denture-associated stomatitis is a common candidal infection that may give rise to painful oral symptoms, as well as be a reservoir for infection at other sites of the body. As poly (methyl methacrylate) (PMMA) remains the main material employed in the fabrication of dentures, the aim of this research was to evaluate the adhesion of Candida albicans cells onto PMMA surfaces by employing an atomic force microscopy (AFM) single-cell force spectroscopy (SCFS) technique. For experiments, tipless AFM cantilevers were functionalized with PMMA microspheres and probed against C. albicans cells immobilized onto biopolymer-coated substrates. Both a laboratory strain and a clinical isolate of C. albicans were used for SCFS experiments. Scanning electron microscopy (SEM) and AFM imaging of C. albicans confirmed the polymorphic behavior of both strains, which was dependent on growth culture conditions. AFM force-spectroscopy results showed that the adhesion of C. albicans to PMMA is morphology dependent, as hyphal tubes had increased adhesion compared with yeast cells ( P < 0.05). C. albicans budding mother cells were found to be nonadherent, which contrasts with the increased adhesion observed in the tube region. Comparison between strains demonstrated increased adhesion forces for a clinical isolate compared with the lab strain. The clinical isolate also had increased survival in blood and reduced sensitivity to complement opsonization, providing additional evidence of strain-dependent differences in Candida-host interactions that may affect virulence. In conclusion, PMMA-modified AFM probes have shown to be a reliable technique to characterize the adhesion of C. albicans to acrylic surfaces.

  8. 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

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

    PubMed

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

    2017-10-01

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

  10. White-opaque switching in natural MTLa/α isolates of Candida albicans: evolutionary implications for roles in host adaptation, pathogenesis, and sex.

    PubMed

    Xie, Jing; Tao, Li; Nobile, Clarissa J; Tong, Yaojun; Guan, Guobo; Sun, Yuan; Cao, Chengjun; Hernday, Aaron D; Johnson, Alexander D; Zhang, Lixin; Bai, Feng-Yan; Huang, Guanghua

    2013-01-01

    Phenotypic transitions play critical roles in host adaptation, virulence, and sexual reproduction in pathogenic fungi. A minority of natural isolates of Candida albicans, which are homozygous at the mating type locus (MTL, a/a or α/α), are known to be able to switch between two distinct cell types: white and opaque. It is puzzling that white-opaque switching has never been observed in the majority of natural C. albicans strains that have heterozygous MTL genotypes (a/α), given that they contain all of the opaque-specific genes essential for switching. Here we report the discovery of white-opaque switching in a number of natural a/α strains of C. albicans under a condition mimicking aspects of the host environment. The optimal condition for white-to-opaque switching in a/α strains of C. albicans is to use N-acetylglucosamine (GlcNAc) as the sole carbon source and to incubate the cells in 5% CO2. Although the induction of white-to-opaque switching in a/α strains of C. albicans is not as robust as in MTL homozygotes in response to GlcNAc and CO2, opaque cells of a/α strains exhibit similar features of cellular and colony morphology to their MTL homozygous counterparts. Like MTL homozygotes, white and opaque cells of a/α strains differ in their behavior in different mouse infection models. We have further demonstrated that the transcriptional regulators Rfg1, Brg1, and Efg1 are involved in the regulation of white-to-opaque switching in a/α strains. We propose that the integration of multiple environmental cues and the activation and inactivation of a set of transcriptional regulators controls the expression of the master switching regulator WOR1, which determines the final fate of the cell type in C. albicans. Our discovery of white-opaque switching in the majority of natural a/α strains of C. albicans emphasizes its widespread nature and importance in host adaptation, pathogenesis, and parasexual reproduction.

  11. White-Opaque Switching in Natural MTLa/α Isolates of Candida albicans: Evolutionary Implications for Roles in Host Adaptation, Pathogenesis, and Sex

    PubMed Central

    Nobile, Clarissa J.; Tong, Yaojun; Guan, Guobo; Sun, Yuan; Cao, Chengjun; Hernday, Aaron D.; Johnson, Alexander D.; Zhang, Lixin; Bai, Feng-Yan; Huang, Guanghua

    2013-01-01

    Phenotypic transitions play critical roles in host adaptation, virulence, and sexual reproduction in pathogenic fungi. A minority of natural isolates of Candida albicans, which are homozygous at the mating type locus (MTL, a/a or α/α), are known to be able to switch between two distinct cell types: white and opaque. It is puzzling that white-opaque switching has never been observed in the majority of natural C. albicans strains that have heterozygous MTL genotypes (a/α), given that they contain all of the opaque-specific genes essential for switching. Here we report the discovery of white-opaque switching in a number of natural a/α strains of C. albicans under a condition mimicking aspects of the host environment. The optimal condition for white-to-opaque switching in a/α strains of C. albicans is to use N-acetylglucosamine (GlcNAc) as the sole carbon source and to incubate the cells in 5% CO2. Although the induction of white-to-opaque switching in a/α strains of C. albicans is not as robust as in MTL homozygotes in response to GlcNAc and CO2, opaque cells of a/α strains exhibit similar features of cellular and colony morphology to their MTL homozygous counterparts. Like MTL homozygotes, white and opaque cells of a/α strains differ in their behavior in different mouse infection models. We have further demonstrated that the transcriptional regulators Rfg1, Brg1, and Efg1 are involved in the regulation of white-to-opaque switching in a/α strains. We propose that the integration of multiple environmental cues and the activation and inactivation of a set of transcriptional regulators controls the expression of the master switching regulator WOR1, which determines the final fate of the cell type in C. albicans. Our discovery of white-opaque switching in the majority of natural a/α strains of C. albicans emphasizes its widespread nature and importance in host adaptation, pathogenesis, and parasexual reproduction. PMID:23555196

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

    PubMed

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

    2015-06-01

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

  13. 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

  14. Evaluation of a rapid immunochromatographic assay for identification of Candida albicans and Candida dubliniensis.

    PubMed

    Marot-Leblond, Agnes; Grimaud, Linda; David, Sandrine; Sullivan, Derek J; Coleman, David C; Ponton, Jose; Robert, Raymond

    2004-11-01

    Candida dubliniensis was first established as a novel yeast species in 1995. It is particularly associated with recurrent episodes of oral candidosis in human immunodeficiency virus (HIV)-infected patients, but it has also been detected at other anatomical sites and at a low incidence level in non-HIV-infected patients. It shares so many phenotypic characteristics with C. albicans that it is easily misidentified as such. No rapid, simple, and commercial test that allows differentiation between C. dubliniensis and C. albicans has been developed, until now. Accurate species identification requires the use of genotype-based techniques that are not routinely available in most clinical microbiology diagnostic laboratories. The present study was designed to evaluate the efficiency of a new test (the immunochromatographic membrane [ICM] albi-dubli test; SR2B, Avrille, France) to differentiate between C. albicans and C. dubliniensis. The organisms evaluated were strains whose identities had previously been confirmed by PCR tests and freshly isolated clinical strains and included 58 C. albicans isolates, 60 C. dubliniensis isolates, and 82 isolates belonging to other species of yeast. The ICM albi-dubli test is based on the principle of immunochromatographic analysis and involves the use of two distinct monoclonal antibodies that recognize two unrelated epitopes expressed by both species or specific to only one species. The assay requires no complex instrumentation for analysis and can be recommended for routine use in clinical microbiology laboratories. Results are obtained within 2 h and 30 min and are easy to interpret. This evaluation demonstrated the good performance of this immunochromatographic test for C. albicans and C. dubliniensis isolated on Sabouraud dextrose agar, CHOROMagar Candida, and CandidaSelect, with sensitivities and specificities ranging from 93.1 to 100%. These parameters decreased, however, to 91.4% when the test was performed with yeast isolated

  15. Synergistic Effects of Honey and Propolis toward Drug Multi-Resistant Staphylococcus Aureus, Escherichia Coli and Candida Albicans Isolates in Single and Polymicrobial Cultures

    PubMed Central

    AL-Waili, Noori; Al-Ghamdi, Ahmad; Ansari, Mohammad Javed; Al-Attal, Y.; Salom, Khelod

    2012-01-01

    Background: Propolis and honey are natural bee products with wide range of biological and medicinal properties. The study investigated antimicrobial activity of ethyl alcohol extraction of propolis collected from Saudi Arabia (EEPS) and from Egypt (EEPE), and their synergistic effect when used with honey. Single and polymicrobial cultures of antibiotic resistant human pathogens were tested. Material and methods; Staphylococcus aureus (S. aureus),), Escherichia coli (E. coli) and Candida albicans (C.albicans) were cultured in 10-100% (v/v) honey diluted in broth, or 0.08-1.0% (weight/volume) EEPS and EEPE diluted in broth. Four types of polymicrobial cultures were prepared by culturing the isolates with each other in broth (control) and broth containing various concentrations of honey or propolis. Microbial growth was assessed on solid plate media after 24 h incubation. Results; EEPS and EEPE inhibited antibiotic resistant E.coli, and S.aureus, and C.albicans in single and polymicrobial cultures. S.aureus became more susceptible when it was cultured with E.coli or C.albicans or when all cultured together. C.albicans became more susceptible when it was cultured with S.aureus or with E.coli and S. aureus together. The presence of ethyl alcohol or honey potentiated antimicrobial effect of propolis toward entire microbes tested in single or polymicrobial cultures. EEPS had lower MIC toward E.coli and C.albicans than EEPE. When propolis was mixed with honey, EEPS showed lower MIC than EEPE. In addition, honey showed lower MIC toward entire microbes when mixed with EEPS than when it was mixed with EEPE. Conclusion; 1) propolis prevents the growth of the microorganisms in single and mixed microbial cultures, and has synergistic effect when used with honey or ethyl alcohol, 2) the antimicrobial property of propolis varies with geographical origin, and 3) this study will pave the way to isolate active ingredients from honey and propolis to be further tested individually or

  16. The alternative oxidase of Candida albicans causes reduced fluconazole susceptibility.

    PubMed

    Yan, Lan; Li, Miaohai; Cao, Yongbing; Gao, Pinghui; Cao, Yingying; Wang, Yan; Jiang, Yuanying

    2009-10-01

    To evaluate the effect of Candida albicans mitochondrial respiratory status on antifungal azole susceptibility. The inhibitors cyanide and salicylhydroxamic acid (SHAM) were each combined with azoles to examine the effect of the combinations on C. albicans. C. albicans strains deleted for the alternative oxidase (Aox) were also examined for susceptibility to azoles and for the generation of intracellular reactive oxygen species (ROS). A chequerboard microdilution assay was performed on several C. albicans clinical strains including azole-resistant isolates to explore the combined effect of fluconazole and inhibitors of Aox. The induction of the alternative respiratory pathway by cyanide decreased susceptibility to azoles, while the inhibition of alternative respiration by SHAM increased azole susceptibility. It was found that ROS production was increased in the absence of Aox in C. albicans upon treatment by antifungals such as miconazole and benomyl. The combination of fluconazole with SHAM resulted in a synergistic effect on the killing of C. albicans clinical isolates. These results demonstrate that the induction of the alternative respiratory pathway confers reduced susceptibility to antifungal azoles, potentially through a mechanism that involves decreased intracellular ROS production during exposure to antifungal agents.

  17. Caspofungin-induced in-vitro post-antifungal effect and its impact on adhesion related traits of oral Candida dubliniensis and Candida albicans isolates.

    PubMed

    Ellepola, Arjuna Nishantha Bandara; Chandy, Rachel; Khan, Zia Uddin; Samaranayake, Lakshman Perera

    2016-03-01

    Adhesion to buccal epithelial cells (BEC) and denture acrylic surfaces (DAS), germ tube (GT) formation and cell surface hydrophobicity (CSH) are all virulence traits involved in the pathogenicity of Candida. Post-antifungal effect (PAFE) also have a bearing on pathogenicity and virulence of Candida. Candida dubliniensis is associated with oral and systemic candidosis, which can be managed with caspofungin. There is no published information on caspofungin-induced PAFE and its impact on adhesion traits of C. dubliniensis isolates. Thus, the purpose of this investigation was to determine the in vitro duration of PAFE on 20 C. dubliniensis isolates following transient exposure to caspofungin. Furthermore the impacts of caspofungin-induced PAFE on adhesion to BEC and DAS, GT formation and CSH of these isolates were also determined. After establishing the minimum inhibitory concentration (MIC) of caspofungin, C. dubliniensis isolates were exposed to sub-lethal concentrations (×3 MIC) of caspofungin for 1 hr. Thereafter the duration of PAFE, adhesion to BEC and DAS, GT formation and CSH were determined by previously described in-vitro assays. MIC (μg/mL) of C. dubliniensis isolates to caspofungin ranged from 0.004 to 0.19. Caspofungin-induced mean PAFE on C. dubliniensis isolates was 2.17 hr. Exposure to caspofungin suppressed the ability of C. dubliniensis isolates to adhere to BEC and DAS, form GT and CSH by 69.97%, 71.95%, 90.06% and 32.29% (P < 0.001 for all), respectively. Thus, transient exposure of C. dubliniensis isolates to caspofungin produces an antifungal effect not only by suppressing its growth but also by altering its adhesion traits. © 2016 The Societies and John Wiley & Sons Australia, Ltd.

  18. 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

  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. Activity of 2,4-Di-tert-butylphenol produced by a strain of Streptomyces mutabilis isolated from a Saharan soil against Candida albicans and other pathogenic fungi.

    PubMed

    Belghit, S; Driche, E H; Bijani, C; Zitouni, A; Sabaou, N; Badji, B; Mathieu, F

    2016-06-01

    In a search for new antifungal antibiotics active against Candida albicans and others pathogenic fungi, a strain of actinobacteria, designated G61, was isolated from a Saharan soil and tested for its activity against these microorganisms. The analysis of its 16S rDNA sequence showed a similarity level of 100% with Streptomyces mutabilis NBRC 12800(T). The highest anticandidal activities produced by the strain G61 were obtained on Bennett medium in the fourth day of incubation. The active product, extracted by n-butanol, contained one bioactive spot detected on thin layer chromatography plates. It was purified by HPLC and its chemical structure was determined by spectroscopic analyses as 2,4-Di-tert-butylphenol. The minimum inhibitory concentrations (MIC) of this product against several strains of pathogenic microorganisms are interesting.

  1. [Evaluation of mixed biofilm formation between Candida albicans and a variety of bacterial species isolated from peripheral catheters at Tlemcen CHU. First study in Algeria].

    PubMed

    Seghir, A; Boucherit-Otmani, Z; Boucherit, K; Sari-Belkharroubi, L; Anselme-Bertrand, I

    2015-06-01

    Mixed-species biofilms constitute a reservoir of infection for a group of bacteria and yeasts that coexist on the same support. Peripheral venous catheters make up a good surface for the attachment of microorganisms that promote biofilm formation and this requires complex strategies for antimicrobial treatments. No such studies on formation mixed biofilms have ever been conducted in Algeria. Therefore, we evaluated the potential for the formation of mixed-species biofilms by Candida albicans and some bacterial species isolated from peripheral vascular catheters at the University Hospital of Tlemcen, in Algeria. The results obtained showed that C. albicans have the potential to form mixed biofilms with three bacteria (Enterobacter cloacae, Bordetella spp. and Serratia liquefaciens) isolated from the same catheter as the yeasts. The amount of biofilms produced varies depending on the species and the composition of the growth medium. Observations by scanning electron microscopy showed that the structure of the mixed biofilm depends on the surface support the biofilm was formed on, and varies with the species. A competition was noted between bacteria and yeasts; it depends on the composition of the medium and its pH, which both play an important role in promoting the dominance of one over the other. Copyright © 2015. Published by Elsevier Masson SAS.

  2. Relevant and selective activity of Pancratium illyricum L. against Candida albicans clinical isolates: a combined effect on yeast growth and virulence.

    PubMed

    Bonvicini, Francesca; Antognoni, Fabiana; Iannello, Carmelina; Maxia, Andrea; Poli, Ferruccio; Gentilomi, Giovanna Angela

    2014-10-23

    Alkaloids present in plants of the Amaryllidaceae family are secondary metabolites of high biological interest, possessing a wide range of pharmacological activities. In the search for new plant-derived compounds with antimicrobial activities, two alkaloid extracts obtained from bulbs and leaves of Pancratium illyricum L., a plant of the Amarillydaceae family, were tested for their effect on bacterial and yeast growth. The broth microdilution susceptibility test was applied to study the effect of plant extracts on the growth of reference bacterial strains and Candida albicans reference and clinical isolates strains. Extracts obtained from the different parts of the plant were tested and compared with the pure components identified in the extracts. Since matrix metalloproteinase enzymes play a role in the dissemination process of Candida albicans, the effect of the bulb extract and pure alkaloids on in vitro collagenase activity was tested. Cell viability test was carried out on human embryo lung fibroblasts (HEL 299). Whilst both extracts did not show any inhibitory activity against neither Gram positive nor Gram negative bacteria, a strong antifungal activity was detected, in particular for the bulb extract. All clinical isolates were susceptible to the growth inhibitory activity of the bulb extract, with endpoint IC50 values ranging from 1.22 to 78 μg/mL. The pure alkaloids lycorine and vittatine, identified as components of the extract, were also assayed for their capacity of inhibiting the yeast growth, and lycorine turned very active, with endpoint IC50 values ranging from 0.89 to 28.5 μg/mL. A potent inhibition of the in vitro collagenase activity was found in the presence of the bulb extract, and this effect was much higher than that exerted by the pure alkaloids. Viability of cell lines tested was not affected by the extract. Taken together, results suggest that the extract of Pancratium illyricum may act as antifungal agent both directly on the yeast

  3. Distribution of Candida albicans and non-albicans Candida species in oral candidiasis patients: Correlation between cell surface hydrophobicity and biofilm forming activities.

    PubMed

    Muadcheingka, Thaniya; Tantivitayakul, Pornpen

    2015-06-01

    The purposes of this investigation were to study the prevalence of Candida albicans and non-albicans Candida (NAC) species from oral candidiasis patients and evaluate the cell surface hydrophobicity (CSH) and biofilm forming capacity of the clinical isolates Candida species from oral cavity. This study identified a total of 250 Candida strains isolated from 207 oral candidiasis patients with PCR-RFLP technique. CSH value, total biomass of biofilm and biofilm forming ability of 117 oral Candida isolates were evaluated. C. albicans (61.6%) was still the predominant species in oral candidiasis patients with and without denture wearer, respectively, followed by C. glabrata (15.2%), C. tropicalis (10.4%), C. parapsilosis (3.2%), C. kefyr (3.6%), C. dubliniensis (2%), C. lusitaniae (2%), C. krusei (1.6%), and C. guilliermondii (0.4%). The proportion of mixed colonization with more than one Candida species was 18% from total cases. The relative CSH value and biofilm biomass of NAC species were greater than C. albicans (p<0.001). Ninety-two percent of oral isolates NAC species had biofilm forming ability, whereas 78% of C. albicans were biofilm formers. Furthermore, the significant difference of relative CSH values between biofilm formers and non-biofilm formers was observed in the NAC species (p<0.005), whereas the difference was not statistically significant in C. albicans. The frequency of the NAC species colonization in oral cavity was gradually increasing. The possible contributing factors might be high cell surface hydrophobicity and biofilm forming ability. The relative CSH value could be a putative factor for determining biofilm formation ability of the non-albicans Candida species. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Effectiveness of magnetic fluid hyperthermia against Candida albicans cells.

    PubMed

    Chudzik, Barbara; Miaskowski, Arkadiusz; Surowiec, Zbigniew; Czernel, Grzegorz; Duluk, Tomasz; Marczuk, Andrzej; Gagoś, Mariusz

    2016-12-01

    Candida albicans is one of the most frequently isolated fungal pathogens causing opportunistic infections in humans. Targeted magnetic fluid hyperthermia (MFH) is a promising method in thermal therapy facilitating selective heating of pathogen cells like C. albicans. In the paper, we used meso-2,3-dimercaptosuccinic acid (DMSA)-coated magnetic nanoparticles (MNPs) and functionalised anti-C. albicans immunomagnetic nanoparticles (IMNPs) to investigate the potential of MFH in combating C. albicans cells in vitro. Using Mössbauer spectroscopy it was found that synthesised MNPs exhibited superparamagnetic phenomena. On the basis of calorimetric experiments, the maximum SAR (specific absorption rate) was found and a proper concentration of MNPs was established to control the temperature. MFH based on both DMSA-coated MNPs and functionalised anti-C. albicans IMNPs was more effective in combating C. albicans cells in vitro than thermostat hyperthermia. Especially promising results were obtained using functionalised IMNPs, which eradicated most of the pathogen colonies at the temperature of 43 °C.

  5. Ocimum sanctum essential oil inhibits virulence attributes in Candida albicans.

    PubMed

    Khan, Amber; Ahmad, Aijaz; Xess, Immaculata; Khan, Luqman A; Manzoor, Nikhat

    2014-03-15

    Candida albicans is an opportunistic human fungal pathogen which causes disease mainly in immunocompromised patients. Activity of hydrolytic enzymes is essential for virulence of C. albicans and so is the capacity of these cells to undergo transition from yeast to mycelial form of growth. Ocimum sanctum is cultivated worldwide for its essential oil which exhibits medicinal properties. This work evaluates the anti-virulence activity of O. sanctum essential oil (OSEO) on 22 strains of C. albicans (including a standard strain ATCC 90028) isolated from both HIV positive and HIV negative patients. Candida isolates were exposed to sub-MICs of OSEO. In vitro secretion of proteinases and phospholipases was evaluated by plate assay containing BSA and egg yolk respectively. Morphological transition from yeast to filamentous form was monitored microscopically in LSM. For genetic analysis, respective genes associated with morphological transition (HWP1), proteinase (SAP1) and phospholipase (PLB2) were also investigated by Real Time PCR (qRT-PCR). Results were analyzed using Student's t-test. OSEO inhibits morphological transition in C. albicans and had a significant inhibitory effect on extracellular secretion of proteinases and phospholipases. Expression profile of respective selected genes associated with C. albicans virulence by qRT-PCR showed a reduced expression of HWP1, SAP1 and PLB2 genes in cells treated with sub-inhibitory concentrations of OSEO. This work suggests that OSEO inhibits morphological transition in C. albicans and decreases the secretion of hydrolytic enzymes involved in the early stage of infection as well as down regulates the associated genes. Further studies will assess the clinical application of OSEO and its constituents in the treatment of fungal infections.

  6. 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

  7. [Candida albicans endocarditis after pulmonary artery banding].

    PubMed

    Talvard, M; Paranon, S; Dulac, Y; Mansir, T; Kreitmann, B; Acar, P

    2009-08-01

    Endocarditis is uncommon in infants and is exceptionally related to Candida albicans on pulmonary banding. We report on a case in a 7-month-old infant who had pulmonary artery banding for a ventricular septal defect and who presented with candidal endocarditis. Banding was chosen because of the patient's poor trophic and unstable status, which could be risky for surgery involving extracorporeal circulation. A few weeks after the banding, the patient developed systemic Candida infection, which was treated successfully. At 7 months, cardiac failure appeared without fever or inflammatory signs. Cardiac echography showed that the banding was not protective as well as a hyperechogenic image on the pulmonary bifurcation. The angioscan showed a hypodense thrombus. Emergency surgery was performed consisting of pulmonary artery exploration, thrombectomy, and ventricular septal defect closure. The exploration showed a pulmonary artery perforation caused by the infected pseudoaneurysm and the migration of the banding into the pulmonary artery. The anatomopathologic analysis of the vegetation identified multisensitive Candida albicans. After surgery and prolonged antifungal treatment, progression was satisfactory.

  8. Synthesis of melanin pigment by Candida albicans in vitro and during infection.

    PubMed

    Morris-Jones, Rachael; Gomez, Beatriz L; Diez, Soraya; Uran, Martha; Morris-Jones, Stephen D; Casadevall, Arturo; Nosanchuk, Joshua D; Hamilton, Andrew J

    2005-09-01

    Melanins are implicated in the pathogenesis of several important human diseases. This study confirmed the presence of melanin particles in Candida albicans in vitro and during infection. Dark particles were isolated from the digestion of C. albicans cultures and from infected tissue, as established by electron microscopy and immunofluorescence techniques.

  9. Synthesis of Melanin Pigment by Candida albicans In Vitro and during Infection

    PubMed Central

    Morris-Jones, Rachael; Gomez, Beatriz L.; Diez, Soraya; Uran, Martha; Morris-Jones, Stephen D.; Casadevall, Arturo; Nosanchuk, Joshua D.; Hamilton, Andrew J.

    2005-01-01

    Melanins are implicated in the pathogenesis of several important human diseases. This study confirmed the presence of melanin particles in Candida albicans in vitro and during infection. Dark particles were isolated from the digestion of C. albicans cultures and from infected tissue, as established by electron microscopy and immunofluorescence techniques. PMID:16113337

  10. 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. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  11. 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

  12. 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

  13. Occurrence rate of oral Candida albicans in denture wearer patients.

    PubMed

    Daniluk, T; Tokajuk, G; Stokowska, W; Fiedoruk, K; Sciepuk, M; Zaremba, M L; Rozkiewicz, D; Cylwik-Rokicka, D; Kedra, B A; Anielska, I; Górska, M; Kedra, B R

    2006-01-01

    The aim was to determine the fungi occurrence rate in the oral cavity of denture wearer patients in comparison to those without dentures. The examinations were conducted in patients treated in two clinical departments of the University Hospital. Demographic data and those connected with basic diseases were collected and the evaluation concerning dentition and oral hygiene was performed. Samples for mycological examinations from the tongue dorsa, palatal mucosa, and mucosal surfaces of dentures were collected from patients with dentures while tongue and palate swabs were taken from those without dentures. For culture and identify of fungi standard methods were used. Dental and mycological examinations were performed in 95 patients, out of which 57 (60.0%) used complete or partial dentures and 38 (40.0%) had their own dentition (without dentures). Oral cavity revealed only growth of Candida albicans species, more frequently in patients with dentures (38/57; 66.7%) than in those without dentures (11/ 38; 28.9%) (p = 0.0003). C. albicans statistically significantly more frequently was isolated in denture wearer patients with diabetes mellitus (p = 0.0207) and without diabetes (p = 0.0376) comparing to such groups of patients but without dentures. Among 32 patients with diabetes mellitus, 14 (43.8%) revealed C. albicans; this rate was comparable with 9/23 (39.1%) patients without diabetes (p > 0.05). A similar analysis, conducted in 25 surgical patients with abdominal cancer and 15--without--cancers, did not show statistically significant differences in the incidence rate of C. albicans; it also concerned denture wearers (14/16; 87.5%) and non-wearing dentures (5/9; 55.6%) (p > 0.05) with cancer. In 37 (64.9%) wearer patients denture stomatitis was observed, associated mainly with C. albicans infections (29/37; 78.4%). 1) Mycological findings from the present study do not indicate that diabetes mellitus or advanced cancer has a significant effect on oral colonisation by

  14. Purification and comparison of heat shock protein 90 (Hsp90) in Candida albicans isolates from Malaysian and Iranian patients and infected mice.

    PubMed

    Khalili, V; Shokri, H; Khosravi, A R; Akim, A; Amri Saroukolaei, S

    2016-06-01

    The purposes of this study were to purify and compare the concentration ratios of heat shock protein 90 (Hsp90) in clinical isolates of Candida albicans (C. albicans) obtained from Malaysian and Iranian patients and infected mice. Hsp90 was extracted using glass beads and ultracentrifugation from yeast cells and purified by ion exchange chromatography (DEAE-cellulose) and followed by affinity chromatography (hydroxyapatite). Purity of Hsp90 was controlled by SDS-PAGE and its identification was realized by immunoblotting test. The graphs of ion exchange and affinity chromatography showed one peak in all C. albicans isolates obtained from both Malaysian and Iranian samples, infected mice and under high-thermal (42°C) and low-thermal (25°C) shock. In immunoblotting, the location of Hsp90 fragments was obtained around 47, 75 and 82kDa. The least average concentration ratios of Hsp90 were 0.350 and 0.240mg/g for Malaysian and Iranian isolates at 25°C, respectively, while the highest average concentration ratios of Hsp90 were 3.05 and 2.600mg/g for Malaysian and Iranian isolates at 42°C, respectively. There were differences in the ratio amount of Hsp90 between Malaysian isolates (1.01±0.07mg/g) and mice kidneys (1.23±0.28mg/g) as well as between Iranian isolates (0.70±0.19mg/g) and mice kidneys (1.00±0.28mg/g) (P<0.05). The results showed differences in all situations tested including Iranian and Malaysian isolates, samples treated with temperatures (25°C or 42°C) and before and after infecting the mice (37°C), indicating higher virulent nature of this yeast species in high temperature in human and animal models. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  15. 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

  16. 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.

  17. 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

  18. Lipidomics and in Vitro Azole Resistance in Candida albicans

    PubMed Central

    Singh, Ashutosh; Mahto, Kaushal Kumar

    2013-01-01

    Abstract We have shown earlier that fluconazole (FLC) stress induces global changes in the lipidome of Candida albicans in clinically adapted isolates. However, several laboratories have developed adapted in vitro FLC resistant strains of C. albicans to study azole resistance mechanisms. This study aimed to identify the lipid changes associated with FLC resistance in these in vitro adapted isolates. Using comparative lipidomics and principal component and discriminant analyses, we observed gradual changes in several lipid classes and molecular species upon FLC exposure of in vitro resistant C. albicans strains. Although the lipid imprint of FLC in vitro resistant isolates was very distinct from that of clinical isolates of C. albicans, the overall changes in lipid class compositions were similar in both cases. For example, an increased sterol content and depleted sphingolipid levels were the salient features of FLC resistance in both conditions. Taken together, it appears that the overall cellular lipid homeostasis is a critical factor in the observed FLC resistance and in handling FLC stress in both clinical and laboratory situations. The new observations reported herein have implications for more efficacious antifungal drug development as well as understanding host–infectious agent interactions in postgenomics microbiology practice. PMID:23374108

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. Antimicrobial activity of plant extracts on Candida albicans: an in vitro study.

    PubMed

    Doddanna, Sunitha Jagalur; Patel, Shilpa; Sundarrao, Madhusudan Astekar; Veerabhadrappa, Ravindra Setru

    2013-01-01

    Plants as sources of medicinal compounds have continued to play a predominant role in the maintenance of human health since ancient times. Even though several effective antifungal agents are available for oral candida infections, the failure is not uncommon because isolates of Candida albicans may exhibits resistance to the drug during therapy. The present study was conducted to evaluate the antimicrobial effects of few plant extracts on Candida albicans. An additional objective was to identify an alternative, inexpensive, simple, and effective method of preventing and controlling Candida albicans. Fine texture powder or paste form of leaves was soaked in sterile distilled water and 100% ethyl alcohol, which were kept in refrigerator at 4°C for 24 h. Then filtrates were prepared and kept in a hot air oven to get a black shining crystal powder/paste form. Stock solutions of plant extracts were inoculated on petri plates containing species of Candida albicans and incubated at 25 ± 2°C for 72 h. Alcoholic curry leaves showed the maximum zone of inhibition on Candida albicans followed by aqueous tea leaves. The other plant extracts like alcoholic onion leaves, alcoholic tea leaves, alcoholic onion bulb, alcoholic aloe vera, and alcoholic mint leaves also inhibited the growth of Candida albicans but lesser extent. The present study renders few medicinal plants as an alternative medicines to the field of dentistry which can be used adjunct to conventional therapy of oral candidasis.

  4. In vitro synergism of a water insoluble fraction of Uncaria tomentosa combined with fluconazole and terbinafine against resistant non-Candida albicans isolates.

    PubMed

    Moraes, Renata Cougo; Carvalho, Anderson Ramos; Lana, Aline Jacobi Dalla; Kaiser, Samuel; Pippi, Bruna; Fuentefria, Alexandre Meneghello; Ortega, George González

    2017-12-01

    Uncaria tomentosa D.C. (Rubiaceae) has several biological activities, including activity against resistant Candida strains. The synergistic interaction with terbinafine or fluconazole can be an important alternative to overcome this resistance. The potential synergy between a water insoluble fraction (WIF) from Uncaria tomentosa bark and the antifungals terbinafine (TRB) and fluconazole (FLZ) against non-Candida albicans resistant strains was investigated. TRB and FLZ, alone and combined with WIF, were tested by the checkerboard procedure using the micro-dilution technique against seven isolates of Candida glabrata and C. krusei. The molecular interactions occurring outside the cell wall were evaluated by scanning electron microscopy, Fourier transform infrared (FT-IR) and differential scanning calorimetry (DSC) analysis. The checkerboard inhibitory assay demonstrated synergy for WIF:TRB and WIF:FLZ combinations, respectively. The best synergistic cell damage was demonstrated unequivocally for the associations of WIF and TRB (1.95:4.0 μg/mL) and WIF and FLZ (1.95:8.0 μg/mL). The comparison of the FT-IR spectra of the antifungal alone, and in combination with WIF, allows recognizing clear differences in 3000, 1600, 1400, and 700-800 cm(-1) bands. Additionally, modifications on TRB and FLZ thermograms were clearly noticed after their combination with WIF. DSC and infrared analysis demonstrated intermolecular interactions between WIF and either TRB or FLZ. Hence, quite likely the synergistic effect is related to interaction events occurring outside the cell wall between antifungal and cat's claw proanthocyanidins. A direct action on the cell wall is suggested, without connection with the ABC efflux pump mechanism.

  5. 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. © 2014 Blackwell Verlag GmbH.

  6. Discrimination between Candida albicans and Other Pathogenic Species of the Genus Candida by Their Differential Sensitivities to Toxins of a Panel of Killer Yeasts

    PubMed Central

    Buzzini, P.; Martini, A.

    2001-01-01

    The differential sensitivities to toxins produced by a short panel of four killer yeasts allowed discrimination between 91 strains of the yeast Candida albicans and 223 non-C. albicans Candida strains. One hundred percent of C. albicans isolates exhibited negative results to the toxin panel, while 100% of non-C. albicans cultures gave well-defined and reproducible positive results to at least one of the four killer toxins. Among C. albicans strains only 96 and 87% gave germ tube (GT)- and chlamydospore-positive results, respectively. In addition a few GT-false-positive strains were detected among non-C. albicans isolates. Susceptibility to the toxin panel is apparently expressed more consistently than either GT or chlamydospore production and may constitute a promising basis for a new simple and easy-to-use procedure for routine discrimination between the species C. albicans and other species of the genus Candida. PMID:11526179

  7. 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

  8. Acetaldehyde production from ethanol and glucose by non-Candida albicans yeasts in vitro.

    PubMed

    Nieminen, Mikko T; Uittamo, Johanna; Salaspuro, Mikko; Rautemaa, Riina

    2009-12-01

    Major environmental risk factors for upper digestive tract cancers are tobacco smoking, alcohol intake and poor oral hygiene. They all result in increased acetaldehyde (ACH) levels in saliva which has been shown to be carcinogenic. During alcohol challenge the oral microbiota is the main determinant of the local ACH concentration. Many bacteria and Candida albicans have been shown to be capable of ACH production. Moreover, chronic candidal mucositis can be carcinogenic. The ability of non-C. albicans Candida to produce ACH has not been studied. The aim of this study was to explore the ability of non-C. albicans Candida species to produce ACH in vitro during ethanol and glucose incubation. A total of 30 non-C. albicans Candida isolates and one C. albicans reference strain were used. The cells were exposed to 11 mM of ethanol and to 100mM glucose in vitro. ACH was measured by gas chromatography. All Candida isolates produced significant amounts of ACH in ethanol incubation. C. tropicalis isolates were the highest (252.3 microM) and C. krusei isolates were the lowest (54.6 microM) producers of ACH from ethanol. Only C.glabrata produced significant amounts of ACH by fermentation from glucose. Colonization of oral mucosa with a non-C.albicans species such as C. glabrata, capable of producing carcinogenic amounts of ACH from both ethanol and glucose, may contribute to the development of oral cancer.

  9. Pathogenicity of Candida tropicalis and Candida albicans after gastrointestinal inoculation in mice.

    PubMed Central

    Wingard, J R; Dick, J D; Merz, W G; Sandford, G R; Saral, R; Burns, W H

    1980-01-01

    The ability of clinical isolates of Candida albicans and candida tropicalis to invade through normal and damaged gastrointestinal mucosa was determined. Adult mice were treated with either gentamicin or gentamicin and cytarabine. Suspensions of yeast cells (10(7)) were administered through a catheter intraesophageally. Invasion was determined by culturing liver, kidney, and lung tissue from mice sacrificed after 48 h. C. albicans and C. tropicalis were incapable of invading through normal gastrointestinal mucosa in mice treated only with gentamicin. Two isolates of C. tropicalis penetrated the damaged gastrointestinal mucosa in 69% (49 of 71) of mice treated with gentamicin and cytarabine. In contrast, three isolates of C. albicans penetrated he damaged gastrointestinal mucosa in only 23% (14 of 62) of mice. These results suggest that C. tropicalis is more capable of invading through damaged gastrointestinal mucosa than C. albicans. The observations in this mouse model parallel those seen in patients on cytotoxic drugs. Therefore, this model offers a tool for investigation of the pathogenicity of these organisms in a model analogous to the compromised host. Images Fig. 2 PMID:7011986

  10. 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

  11. Triclosan Antagonizes Fluconazole Activity against Candida albicans

    PubMed Central

    Higgins, J.; Pinjon, E.; Oltean, H.N.; White, T.C.; Kelly, S.L.; Martel, C.M.; Sullivan, D.J.; Coleman, D.C.; Moran, G.P.

    2012-01-01

    Triclosan is a broad-spectrum antimicrobial compound commonly used in oral hygiene products. Investigation of its activity against Candida albicans showed that triclosan was fungicidal at concentrations of 16 mg/L. However, at subinhibitory concentrations (0.5-2 mg/L), triclosan antagonized the activity of fluconazole. Although triclosan induced CDR1 expression in C. albicans, antagonism was still observed in cdr1Δ and cdr2Δ strains. Triclosan did not affect fluconazole uptake or alter total membrane sterol content, but did induce the expression of FAS1 and FAS2, indicating that its mode of action may involve inhibition of fatty acid synthesis, as it does in prokaryotes. However, FAS2 mutants did not exhibit increased susceptibility to triclosan, and overexpression of both FAS1 and FAS2 alleles did not alter triclosan susceptibility. Unexpectedly, the antagonistic effect was specific for C. albicans under hypha-inducing conditions and was absent in the non-filamentous efg1Δ strain. This antagonism may be due to the membranotropic activity of triclosan and the unique composition of hyphal membranes. PMID:21972257

  12. 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.

  13. Interplay between Candida albicans and the Mammalian Innate Host Defense

    PubMed Central

    Cheng, Shih-Chin; Joosten, Leo A. B.; Kullberg, Bart-Jan

    2012-01-01

    Candida albicans is both the most common fungal commensal microorganism in healthy individuals and the major fungal pathogen causing high mortality in at-risk populations, especially immunocompromised patients. In this review, we summarize the interplay between the host innate system and C. albicans, ranging from how the host recognizes, responds, and clears C. albicans infection to how C. albicans evades, dampens, and escapes from host innate immunity. PMID:22252867

  14. 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.

  15. 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

  16. Competitive Fitness of Fluconazole-Resistant Clinical Candida albicans Strains.

    PubMed

    Popp, Christina; Hampe, Irene A I; Hertlein, Tobias; Ohlsen, Knut; Rogers, P David; Morschhäuser, Joachim

    2017-07-01

    The pathogenic yeast Candida albicans can develop resistance to the widely used antifungal agent fluconazole, which inhibits ergosterol biosynthesis. Resistance is often caused by gain-of-function mutations in the transcription factors Mrr1 and Tac1, which result in constitutive overexpression of multidrug efflux pumps, and Upc2, which result in constitutive overexpression of ergosterol biosynthesis genes. However, the deregulated gene expression that is caused by hyperactive forms of these transcription factors also reduces the fitness of the cells in the absence of the drug. To investigate whether fluconazole-resistant clinical C. albicans isolates have overcome the fitness costs of drug resistance, we assessed the relative fitness of C. albicans isolates containing resistance mutations in these transcription factors in competition with matched drug-susceptible isolates from the same patients. Most of the fluconazole-resistant isolates were outcompeted by the corresponding drug-susceptible isolates when grown in rich medium without fluconazole. On the other hand, some resistant isolates with gain-of-function mutations in MRR1 did not exhibit reduced fitness under these conditions. In a mouse model of disseminated candidiasis, three out of four tested fluconazole-resistant clinical isolates did not exhibit a significant fitness defect. However, all four fluconazole-resistant isolates were outcompeted by the matched susceptible isolates in a mouse model of gastrointestinal colonization, demonstrating that the effects of drug resistance on in vivo fitness depend on the host niche. Collectively, our results indicate that the fitness costs of drug resistance in C. albicans are not easily remediated, especially when proper control of gene expression is required for successful adaptation to life within a mammalian host. Copyright © 2017 American Society for Microbiology.

  17. 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.

  18. Antifungal susceptibilities of Candida species isolated from urine culture.

    PubMed

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

    2016-09-01

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

  19. Candidal urinary tract infections caused by non-albicans Candida species.

    PubMed

    Dorko, E; Pilipcinec, E; Tkáciková, L

    2002-01-01

    The incidence of non-albicans Candida and non-Candida species isolated from the urine of patients admitted to various departments of the Faculty Hospital of the Medical Faculty of Safárik University in Kosice was examined. From a total of 94 samples of analyzed urine 58 strains of C. albicans and 36 strains of yeasts belonging to 6 species of non-albicans Candida and non-Candida spp. were detected: C. parapsilosis (n = 23), C. tropicalis (6), C. krusei (3), C. robusta (2), C. catenulata (1) and Cryptococcus neoformans (1). In relation to the diagnosis, the yeasts were isolated from patients suffering from a kidneys disease, epididymitis, diabetes, neoplastic diseases, urogenital anomalies, obstructive uropathy, cystitis, prostatitis, hemolytic-uremic syndrome, and others.

  20. Regulation of superoxide dismutase synthesis in Candida albicans.

    PubMed

    Gunasekaran, U; Yang, R; Gunasekaran, M

    1998-01-01

    The synthesis of superoxide dismutase [SOD: EC 1.15.1.1] in response to various cultural conditions was examined in Candida albicans, an opportunistic yeast which causes candidiasis in immunosuppressed patients. SOD plays an important role in protecting cells from teh oxidative damage of superoxide radicals. Maximum SOD activity was found after 72 hrs of yeast growth. The optimum pH and temperature for the SOD activity were 7 and 40 degrees C, respectively. The major SOD activity was found in the cytosol fraction and the level of extracellular SOD was very low. The enzyme was stimulated to varying degrees by cholic acid, procaine and tocopherol. On the basis of inhibitor studies and other enzyme properties, the isolated enzyme from C. albicans is identified as a copper and zinc superoxide dismutase.

  1. 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

  2. Genetic and phenotypic intra-species variation in Candida albicans

    PubMed Central

    Hirakawa, Matthew P.; Martinez, Diego A.; Sakthikumar, Sharadha; Anderson, Matthew Z.; Berlin, Aaron; Gujja, Sharvari; Zeng, Qiandong; Zisson, Ethan; Wang, Joshua M.; Greenberg, Joshua M.; Berman, Judith

    2015-01-01

    Candida albicans is a commensal fungus of the human gastrointestinal tract and a prevalent opportunistic pathogen. To examine diversity within this species, extensive genomic and phenotypic analyses were performed on 21 clinical C. albicans isolates. Genomic variation was evident in the form of polymorphisms, copy number variations, chromosomal inversions, subtelomeric hypervariation, loss of heterozygosity (LOH), and whole or partial chromosome aneuploidies. All 21 strains were diploid, although karyotypic changes were present in eight of the 21 isolates, with multiple strains being trisomic for Chromosome 4 or Chromosome 7. Aneuploid strains exhibited a general fitness defect relative to euploid strains when grown under replete conditions. All strains were also heterozygous, yet multiple, distinct LOH tracts were present in each isolate. Higher overall levels of genome heterozygosity correlated with faster growth rates, consistent with increased overall fitness. Genes with the highest rates of amino acid substitutions included many cell wall proteins, implicating fast evolving changes in cell adhesion and host interactions. One clinical isolate, P94015, presented several striking properties including a novel cellular phenotype, an inability to filament, drug resistance, and decreased virulence. Several of these properties were shown to be due to a homozygous nonsense mutation in the EFG1 gene. Furthermore, loss of EFG1 function resulted in increased fitness of P94015 in a commensal model of infection. Our analysis therefore reveals intra-species genetic and phenotypic differences in C. albicans and delineates a natural mutation that alters the balance between commensalism and pathogenicity. PMID:25504520

  3. Genetic and phenotypic intra-species variation in Candida albicans.

    PubMed

    Hirakawa, Matthew P; Martinez, Diego A; Sakthikumar, Sharadha; Anderson, Matthew Z; Berlin, Aaron; Gujja, Sharvari; Zeng, Qiandong; Zisson, Ethan; Wang, Joshua M; Greenberg, Joshua M; Berman, Judith; Bennett, Richard J; Cuomo, Christina A

    2015-03-01

    Candida albicans is a commensal fungus of the human gastrointestinal tract and a prevalent opportunistic pathogen. To examine diversity within this species, extensive genomic and phenotypic analyses were performed on 21 clinical C. albicans isolates. Genomic variation was evident in the form of polymorphisms, copy number variations, chromosomal inversions, subtelomeric hypervariation, loss of heterozygosity (LOH), and whole or partial chromosome aneuploidies. All 21 strains were diploid, although karyotypic changes were present in eight of the 21 isolates, with multiple strains being trisomic for Chromosome 4 or Chromosome 7. Aneuploid strains exhibited a general fitness defect relative to euploid strains when grown under replete conditions. All strains were also heterozygous, yet multiple, distinct LOH tracts were present in each isolate. Higher overall levels of genome heterozygosity correlated with faster growth rates, consistent with increased overall fitness. Genes with the highest rates of amino acid substitutions included many cell wall proteins, implicating fast evolving changes in cell adhesion and host interactions. One clinical isolate, P94015, presented several striking properties including a novel cellular phenotype, an inability to filament, drug resistance, and decreased virulence. Several of these properties were shown to be due to a homozygous nonsense mutation in the EFG1 gene. Furthermore, loss of EFG1 function resulted in increased fitness of P94015 in a commensal model of infection. Our analysis therefore reveals intra-species genetic and phenotypic differences in C. albicans and delineates a natural mutation that alters the balance between commensalism and pathogenicity.

  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. Pseudomonas phage inhibition of Candida albicans.

    PubMed

    Nazik, Hasan; Joubert, Lydia-Marie; Secor, Patrick R; Sweere, Johanna M; Bollyky, Paul L; Sass, Gabriele; Cegelski, Lynette; Stevens, David A

    2017-10-06

    Pseudomonas aeruginosa (Pa) and Candida albicans (Ca) are major bacterial and fungal pathogens in immunocompromised hosts, and notably in the airways of cystic fibrosis patients. The bacteriophages of Pa physically alter biofilms, and were recently shown to inhibit the biofilms of Aspergillus fumigatus. To understand the range of this viral-fungal interaction, we studied Pa phages Pf4 and Pf1, and their interactions with Ca biofilm formation and preformed Ca biofilm. Both forms of Ca biofilm development, as well as planktonic Ca growth, were inhibited by either phage. The inhibition of biofilm was reversed by the addition of iron, suggesting that the mechanism of phage action on Ca involves denial of iron. Birefringence studies on added phage showed an ordered structure of binding to Ca. Electron microscopic observations indicated phage aggregation in the biofilm extracellular matrix. Bacteriophage-fungal interactions may be a general feature with several pathogens in the fungal kingdom.

  6. Acid production by oral strains of Candida albicans and lactobacilli.

    PubMed

    Klinke, T; Kneist, S; de Soet, J J; Kuhlisch, E; Mauersberger, S; Forster, A; Klimm, W

    2009-01-01

    Both Candida albicans and lactobacilli are common colonizers of carious lesions in children and adolescents. The purpose of this study is to compare the velocity of acid production between C. albicans and several Lactobacillus species at different pH levels and concentrations of glucose. Washed, pure resting-cell suspensions were obtained by culturing a total of 28 oral isolates comprising the species C. albicans, Lactobacillus rhamnosus, Lactobacillus paracasei paracasei, Lactobacillus paracasei tolerans and Lactobacillus delbrueckii lactis. Acid production from glucose was determined at a constant pH of 7.0, 5.5, 5.0 and 4.0 by repeated titrations with NaOH in an automated pH-stat system. Acid formation rates of yeast and lactobacilli proved to be similar at both neutral and low pH, while in a moderately acidic environment C. albicans produced less acid than the lactobacilli. Ion chromatographic analysis of the cell-free medium after titration revealed pyruvate to be the predominant organic acid anion secreted by C. albicans. The proportion of organic acids to overall acid production by the yeast was below 10% at neutral conditions, in contrast to 42-66% at pH 4.0. Compared to lactobacilli, yeast required a concentration of glucose that was about 50 times higher to allow acid production at half the maximum speed. Considering the clinical data in the literature about the frequency and proportions of microorganisms present in early childhood caries lesions, the contribution of oral lactobacilli as well as C. albicans to overall microbial acid formation appears to be important.

  7. Ribosomal RNA processing in Candida albicans

    PubMed Central

    Pendrak, Michael L.; Roberts, David D.

    2011-01-01

    Ribosome assembly begins with conversion of a polycistronic precursor into 18S, 5.8S, and 25S rRNAs. In the ascomycete fungus Candida albicans, rRNA transcription starts 604 nt upstream of the 18S rRNA junction (site A1). One major internal processing site in the 5′ external transcribed spacer (A0) occurs 108 nt from site A1. The A0–A1 fragment persists as a stable species during log phase growth and can be used to assess proliferation rates. Separation of the small and large subunit pre-rRNAs occurs at sites A2 and A3 in internal transcribed spacer-1 Saccharomyces cerevisiae pre-rRNA. However, the 5′ end of the 5.8S rRNA is represented by only a 5.8S (S) form, and a 7S rRNA precursor of the 5.8S rRNA extends into internal transcribed spacer 1 to site A2, which differs from S. cerevisiae. External transcribed spacer 1 and internal transcribed spacers 1 and 2 show remarkable structural similarity with S. cerevisiae despite low sequence identity. Maturation of C. albicans rRNA resembles other eukaryotes in that processing can occur cotranscriptionally or post-transcriptionally. During rapid proliferation, U3 snoRNA-dependent processing occurs before large and small subunit rRNA separation, consistent with cotranscriptional processing. As cells pass the diauxic transition, the 18S pre-rRNA accumulates into stationary phase as a 23S species, possessing an intact 5′ external transcribed spacer extending to site A3. Nutrient addition to starved cells results in the disappearance of the 23S rRNA, indicating a potential role in normal physiology. Therefore, C. albicans reveals new mechanisms that regulate post- versus cotranscriptional rRNA processing. PMID:22028364

  8. Budding off: bringing functional genomics to Candida albicans

    PubMed Central

    Anderson, Matthew Z.

    2016-01-01

    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. PMID:26424829

  9. 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. © The Author 2015. Published by Oxford University Press. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  10. 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

  11. Lemongrass-Incorporated Tissue Conditioner Against Candida albicans Culture

    PubMed Central

    Amornvit, Pokpong; Srithavaj, Theerathavaj

    2014-01-01

    Background: Tissue conditioner is applied popularly with dental prosthesis during wound healing process but it becomes a reservoir of oral microbiota, especially Candida species after long-term usage. Several antifungal drugs have been mixed with this material to control fungal level. In this study, lemongrass essential oil was added into COE-COMFORT tissue conditioner before being determined for anti-Candida efficacy. Materials and Methods: Lemongrass (Cymbopogon citratus) essential oil was primarily determined for antifungal activity against C. albicans American type culture collection (ATCC) 10231 and MIC (minimum inhibitory concentration) value by agar disk diffusion and broth microdilution methods, respectively. COE-COMFORT tissue conditioner was prepared as recommended by the manufacturer after a fixed volume of the oil at its MIC or higher concentrations were mixed thoroughly in its liquid part. Antifungal efficacy of the tissue conditioner with/without herb was finally analyzed. Results: Lemongrass essential oil displayed potent antifungal activity against C. albicans ATCC 10231and its MIC value was 0.06% (v/v). Dissimilarly, the tissue conditioner containing the oil at MIC level did not cease the growth of the tested fungus. Both reference and clinical isolates of C. albicans were completely inhibited after exposed to the tissue conditioner containing at least 0.25% (v/v) of the oil (approximately 4-time MIC). The tissue conditioner without herb or with nystatin was employed as negative or positive control, respectively. Conclusion: COE-COMFORT tissue conditioner supplemented with lemongrass essential oil obviously demonstrated another desirable property as in vitro anti-Candida efficacy to minimize the risk of getting Candidal infection. PMID:25177638

  12. Influence of Candida krusei and Candida glabrata on Candida albicans gene expression in in vitro biofilms.

    PubMed

    Barros, Patrícia Pimentel; Ribeiro, Felipe Camargo; Rossoni, Rodnei Dennis; Junqueira, Juliana Campos; Jorge, Antonio Olavo Cardoso

    2016-04-01

    The present study aimed to evaluate the interactions between the species Candida albicans, Candida krusei and Candida glabrata in monotypic and mixed biofilm models formed in vitro as well as the relative expression of the ALS1, ALS3, HWP1, BCR1, EFG1, TEC1, SAP5, PLB2 and LIP9 genes. Mixed (C. albicans/C. krusei and C. albicans/C. glabrata) and monotypic biofilms were cultured for 0, 12 and 24h. Gene expression was analyzed in the same biofilm model in which the number of CFU/mL was counted. The C. albicans CFU/mL values were lower at the 12 and 24h time points in the mixed biofilms compared with the monotypic biofilms, and decreases of 56.23% and 64.4% in C. albicans were observed when this species was associated with C. glabrata and C. krusei, respectively. In the presence of C. krusei, the expression of the ALS3, HWP1, BCR1, EFG1 and TEC1 genes of C. albicans was completely inhibited, indicating both transcriptome and the phenotypic antagonism between these two species, but genes related to the secretion of enzymes were stimulated. In the presence of C. glabrata, C. albicans showed a similar gene expression profile to that obtained in association with C. krusei, though it was altered to a lesser degree. We conclude that C. krusei and C. glabrata may alter or inhibit the mechanisms involved in the in vitro adherence and formation of C. albicans biofilms, influencing the pathogenicity of this species and suggesting a competitive interaction with C. krusei and C. glabrata in biofilm formation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Effect of Low-Level Laser therapy on the fungal proliferation of Candida albicans

    NASA Astrophysics Data System (ADS)

    Carneiro, Vanda S. M.; Araújo, Natália C.; Menezes, Rebeca F. d.; Moreno, Lara M.; Santos-Neto, Alexandrino d. P.; Gerbi, Marleny Elizabeth M.

    2016-03-01

    Candida albicans plays an important role in triggering infections in HIV+ patients. The indiscriminate use of antifungals has led to resistance to Candida albicans, which requires new treatment alternatives for oral candidiasis. Low-level laser therapy promotes a considerable improvement in the healing of wounds and in curing illnesses caused by microorganisms. The aim of the present study was to assess the effect of laser radiation on the cell proliferation of Candida albicans in immunosuppressed patients. Six Candida albicans strains that had been isolated from immunosuppressed patients were divided into a control group and experimental groups, which received eight sessions of laser therapy (InGaAlP, λ685nm, P = 30mW, CW, Φ~6 mm and GaAlAs, λ830nm, P = 40mW, CW, Φ~6 mm) using dosimetries of 6J/cm2, 8J/cm2, 10J/cm2 and 12J/cm2 for each wavelength and power. The results were not statistically significant (Kruskal Wallis, p > 0.05), although the proliferation of Candida albicans was lower in some of the experimental groups. The dosimetry of 6J/cm2 (GaAlAs, λ830nm, P = 40mW) provided lower mean scores than the other groups for the growth of Candida. Further studies are required to confirm whetehr laser therapy is a viable option in the treatment of fungal infections.

  14. 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. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Distribution of Candida albicans genotypes among family members

    NASA Technical Reports Server (NTRS)

    Mehta, S. K.; Stevens, D. A.; Mishra, S. K.; Feroze, F.; Pierson, D. L.

    1999-01-01

    Thirty-three families (71 subjects) were screened for the presence of Candida albicans in mouthwash or stool specimens; 12 families (28 subjects) were culture-positive for this yeast. An enrichment procedure provided a twofold increase in the recovery of C. albicans from mouthwash specimens. Nine of the twelve culture-positive families had two positive members each, two families had three positive members each, and one family had four positive members. Genetic profiles were obtained by three methods: pulsed-field gel electrophoresis; restriction endonuclease analysis, and random amplification of polymorphic DNA analysis. DNA fingerprinting of C. albicans isolated from one body site three consecutive times revealed that each of the 12 families carried a distinct genotype. No two families shared the same strain, and two or more members of a family commonly shared the same strain. Intrafamily genotypic identity (i.e., each member within the family harbored the same strain) was demonstrated in six families. Genotypes of isolates from husband and wife differed from one another in five families. All three methods were satisfactory in determining genotypes; however, we concluded that restriction endonuclease analysis provided adequate resolving power.

  16. In Vitro Antifungal Activity of Equol against Candida albicans

    PubMed Central

    Lee, Jeong Ah

    2010-01-01

    In this study, we demonstrate that equol has fungicidal activities against Candida albicans. The minimum inhibitory and minimum fungicidal concentrations of equol against C. albicans were 516 and 1,032 µM, respectively. Two separate viability assays found that equol changed the integrity of the C. albicans cell membrane, possibly by formation of membrane lesions. Scanning electron microscopy demonstrated ultrastructural changes. PMID:23956675

  17. Detection of Antibodies to Candida albicans Germ Tubes during Experimental Infections by Different Candida Species

    PubMed Central

    Bikandi, Joseba; San Millán, Rosario; Regúlez, Pilar; Moragues, María D.; Quindós, Guillermo; Pontón, José

    1998-01-01

    Identification and characterization of Candida albicans germ tube-specific antigens may be of relevance for the serodiagnosis of invasive candidiasis since they could be the basis for the development of new diagnostic tests. In this study, we have identified two antigens of 180 and >200 kDa in the cell wall of C. albicans germ tubes which are responsible for the induction of antibodies to C. albicans germ tubes. Antigens of similar molecular masses have been demonstrated in the cell walls of the Candida species C. stellatoidea, C. parapsilosis, C. guilliermondii, C. tropicalis, and C. krusei, but not C. glabrata. The kinetics of the antibody responses to C. albicans germ tubes were studied in rabbits infected with different Candida species. Although these antibodies were detected in rabbits infected with all Candida species except C. glabrata, the kinetics of the antibody responses to C. albicans germ tubes induced by the Candida species studied were different. Both the highest titer and the earliest response of antibodies to C. albicans germ tubes were observed in rabbits infected with either of the two serotypes of C. albicans used. However, the time needed to elicit the antibodies to C. albicans germ tubes can be reduced as the result of an anamnestic antibody response. The results presented in this study show that a test designed to detect antibodies against C. albicans germ tube antigens may be suitable for the diagnosis of infections caused by most of the medically important Candida species. PMID:9605993

  18. [High molecular weight chitosan and sodium alginate effect on secretory acid proteinase of Candida albicans].

    PubMed

    Calamari, Silvia; Bojanich, Alejandra; Barembaum, Silvina; Azcurra, Ana; Virga, Carolina; Dorronsoro, Susana

    2004-12-01

    The effect of high molecular weight chitosan (HMWCh) and sodium alginate (NaAL) on acid proteinase secretion of Candida albicans (one of culture collection and five isolates) was evaluated. The secretion of acid proteinase was induced in the presence and the absence of these polymers in different concentrations and their enzymatic activity was determined. HMWCh and NaAL significantly diminished the enzymatic activity (>76% for the collection strains and > 89% for the isolates, p < 0.05). HMWCh did not modify protein concentrations, but NaAL did. It can be concluded that both polymers can inhibit the proteinase activity of Candida albicans.

  19. Purification and characterisation of a metallopeptidase of Candida albicans.

    PubMed

    el Moudni, B; Rodier, M H; Barrault, C; Ghazali, M; Jacquemin, J L

    1995-10-01

    A novel aminopeptidase was purified by high performance liquid chromatography from a cytosoluble 100,000 g extract of Candida albicans on the basis of its ability to cleave L-arginine 7-amino-4-methylcoumarin. The purification factor was 36 and the yield was 20%. The native enzyme had a mol. wt of 52 kDa as demonstrated by SDS-PAGE in the presence or absence of reducing conditions and exhibited an iso-electric point of 4.3. The aminopeptidase showed optimum activity at pH 7.2, a Michaelis constant of c. 50 microM and a Vmax at 19 mM AMC released/min/mg of protein for L-Arg-AMC. This enzyme was shown to cleave at low affinity L-leucine-7-amino-4-methylcoumarin as demonstrated by the spectrofluorimetric method. The enzyme was strongly inhibited by specific metallo-enzyme inhibitors-EDTA and o-phenanthroline. Furthermore, there is evidence that a similar or identical enzyme occurs in other C. albicans clinical isolates and other Candida spp.

  20. 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

  1. The synthetic killer peptide KP impairs Candida albicans biofilm in vitro

    PubMed Central

    Paulone, Simona; Ardizzoni, Andrea; Tavanti, Arianna; Piccinelli, Serena; Rizzato, Cosmeri; Lupetti, Antonella; Colombari, Bruna; Pericolini, Eva; Polonelli, Luciano; Magliani, Walter; Conti, Stefania; Posteraro, Brunella; Cermelli, Claudio; Peppoloni, Samuele

    2017-01-01

    Candida albicans is a commensal organism, commonly inhabiting mucosal surfaces of healthy individuals, as a part of the resident microbiota. However, in susceptible hosts, especially hospitalized and/or immunocompromised patients, it may cause a wide range of infections. The presence of abiotic substrates, such as central venous or urinary catheters, provides an additional niche for Candida attachment and persistence, particularly via biofilm development. Furthermore, Candida biofilm is poorly susceptible to most antifungals, including azoles. Here we investigated the effects of a synthetic killer peptide (KP), known to be active in vitro, ex vivo and/or in vivo against different pathogens, on C. albicans biofilm. Together with a scrambled peptide used as a negative control, KP was tested against Candida biofilm at different stages of development. A reference strain, two fluconazole-resistant and two fluconazole-susceptible C. albicans clinical isolates were used. KP-induced C. albicans oxidative stress response and membrane permeability were also analysed. Moreover, the effect of KP on transcriptional profiles of C. albicans genes involved in different stages of biofilm development, such as cell adhesion, hyphal development and extracellular matrix production, was evaluated. Our results clearly show that the treatment with KP strongly affected the capacity of C. albicans to form biofilm and significantly impairs preformed mature biofilm. KP treatment resulted in an increase in C. albicans oxidative stress response and membrane permeability; also, biofilm-related genes expression was significantly reduced. Comparable inhibitory effects were observed in all the strains employed, irrespective of their resistance or susceptibility to fluconazole. Finally, KP-mediated inhibitory effects were observed also against a catheter-associated C. albicans biofilm. This study provides the first evidence on the KP effectiveness against C. albicans biofilm, suggesting that KP may

  2. The synthetic killer peptide KP impairs Candida albicans biofilm in vitro.

    PubMed

    Paulone, Simona; Ardizzoni, Andrea; Tavanti, Arianna; Piccinelli, Serena; Rizzato, Cosmeri; Lupetti, Antonella; Colombari, Bruna; Pericolini, Eva; Polonelli, Luciano; Magliani, Walter; Conti, Stefania; Posteraro, Brunella; Cermelli, Claudio; Blasi, Elisabetta; Peppoloni, Samuele

    2017-01-01

    Candida albicans is a commensal organism, commonly inhabiting mucosal surfaces of healthy individuals, as a part of the resident microbiota. However, in susceptible hosts, especially hospitalized and/or immunocompromised patients, it may cause a wide range of infections. The presence of abiotic substrates, such as central venous or urinary catheters, provides an additional niche for Candida attachment and persistence, particularly via biofilm development. Furthermore, Candida biofilm is poorly susceptible to most antifungals, including azoles. Here we investigated the effects of a synthetic killer peptide (KP), known to be active in vitro, ex vivo and/or in vivo against different pathogens, on C. albicans biofilm. Together with a scrambled peptide used as a negative control, KP was tested against Candida biofilm at different stages of development. A reference strain, two fluconazole-resistant and two fluconazole-susceptible C. albicans clinical isolates were used. KP-induced C. albicans oxidative stress response and membrane permeability were also analysed. Moreover, the effect of KP on transcriptional profiles of C. albicans genes involved in different stages of biofilm development, such as cell adhesion, hyphal development and extracellular matrix production, was evaluated. Our results clearly show that the treatment with KP strongly affected the capacity of C. albicans to form biofilm and significantly impairs preformed mature biofilm. KP treatment resulted in an increase in C. albicans oxidative stress response and membrane permeability; also, biofilm-related genes expression was significantly reduced. Comparable inhibitory effects were observed in all the strains employed, irrespective of their resistance or susceptibility to fluconazole. Finally, KP-mediated inhibitory effects were observed also against a catheter-associated C. albicans biofilm. This study provides the first evidence on the KP effectiveness against C. albicans biofilm, suggesting that KP may

  3. 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.

  4. Role of Non Albicans Candida Spp. and Biofilm in Neonatal ICU.

    PubMed

    Goel, Shagun; Mittal, Seema; Chaudhary, Uma

    2016-01-01

    Candida spp. remains the fungal species most commonly associated with biofilm formation. Increase in Candida infections in last decades has almost paralleled the increase and wide spread use of a broad range of medical implant devices mainly in population with impaired host defences. One of the most important characteristics of biofilms is their high level of resistance to antimicrobial drugs. This study was conducted to know the prevalence of different Candida spp. causing blood stream infections and ability to form biofilm and to evaluate the co relation of biofilm with antifungal drug resistance. The present study was conducted on 12464 blood samples for the identification and speciation of various Candida spp. causing blood stream infection over a period of one year. Antifungal susceptibility was performed as per clinical laboratory standard institute guidelines and biofilm formation was detected by method described by Christensen's et al. Out of total 12464 blood culture received, 1378 (11.05%) were culture positive rest and among culture positive 100 (7.25%) Candida isolates were recovered. C. tropicalis was the commonest (43%) species followed by C. albicans (41%), C. krusei (9%) and C. parapsilosis (7%). A total of 41 Candida isolates were biofilm producers and rest 59 isolates were non-biofilm producers. A changing trend of increased prevalence of non albicans Candida spp. was observed which were resistant to commonly used antifungal fluconazole. Multi drug resistance was more common in biofilm forming Candida isolates.

  5. Fluconazole Susceptibility and Genotypic Heterogeneity of Oral Candida albicans Colonies from the Patients with Cancer Receiving Chemotherapy in China

    PubMed Central

    Sun, Jing; Qi, Cheng; Lafleur, Micheal D; Qi, Qing-guo

    2009-01-01

    Aim To identify heterogeneity of Candida albicans (C. albicans) isolated from the population with cancer in China by using identification medium, subculture molecular typing, and antifungal susceptibility test. Methodology Oral cheek mucosal specimens from 52 cancer patients receiving chemotherapy were cultured on CHROMagar CandidaTM plates for Candida identification. All the C. albicans colonies on the plates were subcultured and reconfirmed by API20C, then submitted to the antifungal drug susceptibility test with fluconazole and molecular typing using randomly amplified polymorphic DNA-PCR (RAPD) with primers RSD6 and RSD12. Results 54% (28/52) patients were oral yeast carriage in which C. albicans predominated. More than 7 C. albicans colonies were isolated from each of 12 patients (Group A), while less than 5 colonies were isolated from each of 16 patients (Group B). RSD6 and RSD12 were successful in eliciting 17 (A1-A17) and 2 (B1-B2) genotypes, respectively from among the 205 isolates. The two primers were combined to generate 21 genotypes. The C. albicans isolates obtained from the same patient and episode showed a diversity for fluconazole revealed by MIC50 and MIC90. Conclusion The heterogeneity of the C. albicans colonies isolated from the same patients can be detected. C. albicans with varied fluconazole susceptibility and genotypic characteristics may coexist in the same oral Candida population. PMID:20695081

  6. 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

  7. Person-to-person transfer of Candida albicans in the spacecraft environment

    NASA Technical Reports Server (NTRS)

    Pierson, D. L.; Mehta, S. K.; Magee, B. B.; Mishra, S. K.

    1995-01-01

    We assessed the exchange of Candida albicans among crew members during 10 Space Shuttle missions. Throat, nasal, urine and faecal specimens were collected from 61 crew members twice before and once after space flights ranging from 7 to 10 days in duration; crews consisted of groups of five, six or seven men and women. Candida albicans was isolated at least once from 20 of the 61 subjects (33%). Candida strains were identified by restriction-fragment length polymorphism (RFLP) after digestion by the endonucleases EcoRI and HinfI; further discrimination was gained by Southern blot hybridization with the C. albicans repeat fragment 27A. Eighteen of the 20 Candida-positive crew members carried different strains of C. albicans in the specimens collected. Possible transfer of C. albicans between members of the same crew was demonstrated only once in the 10 missions studied. We conclude that the transfer of C. albicans among crew members during Space Shuttle flights is less frequent than had been predicted from earlier reports.

  8. Chlorhexidine markedly potentiates the oxidants scavenging abilities of Candida albicans.

    PubMed

    Ginsburg, I; Koren, E; Feuerstein, O; Zogakis, I P; Shalish, M; Gorelik, S

    2015-10-01

    The oxidant scavenging ability (OSA) of catalase-rich Candida albicans is markedly enhanced by chlorhexidine digluconate (CHX), polymyxin B, the bile salt ursodeoxycholate and by lysophosphatidylcholine, which all act as detergents facilitating the penetration of oxidants and their intracellular decomposition. Quantifications of the OSA of Candida albicans were measured by a highly sensitive luminol-dependent chemiluminescence assay and by the Thurman's assay, to quantify hydrogen peroxide (H2O2). The OSA enhancing activity by CHX depends to some extent on the media on which candida grew. The OSA of candida treated by CHX was modulated by whole human saliva, red blood cells, lysozyme, cationic peptides and by polyphenols. Concentrations of CHX, which killed over 95 % of Candida albicans cells, did not affect the cells' abilities to scavenge reactive oxygen species (ROS). The OSA of Candida cells treated by CHX is highly refractory to H2O2 (50 mM) but is strongly inhibited by hypochlorous acid, lecithin, trypan blue and by heparin. We speculate that similarly to catalase-rich red blood cells, Candida albicans and additional catalase-rich microbiota may also have the ability to scavenge oxidants and thus can protect catalase-negative anaerobes and facultative anaerobes cariogenic streptococci against peroxide and thus secure their survival in the oral cavity.

  9. 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

  10. Dose-dependent effect of lysozyme upon Candida albicans biofilm

    PubMed Central

    Sebaa, Sarra; Hizette, Nicolas; Boucherit-Otmani, Zahia; Courtois, Philippe

    2017-01-01

    The present study investigated the in vitro effect of lysozyme (0–1,000 µg/ml) on Candida albicans (C. albicans) biofilm development. Investigations were conducted on C. albicans ATCC 10231 and on 10 clinical isolates from dentures. Strains were cultured aerobically at 37°C in Sabouraud broth. Yeast growth was evaluated by turbidimetry. Biofilm biomass was quantified on a polystyrene support by crystal violet staining and on acrylic surfaces by counts of colony forming units. Lysozyme affected biofilm formation to a greater extent than it affected growth. For the ATCC 10231 reference strain, lysozyme acted as a biofilm promotor on polystyrene at the highest concentration tested (1,000 µg/ml, non-physiological). When the reference strain was investigated on acrylic resin support, lysozyme acted as a significant biofilm promotor on rough resin, but less on smooth resin. The attached biomass in the presence of physiological concentrations of lysozyme (10–30 µg/ml) was significantly decreased compared with the hypothetical value of 100% using a one-sample t-test, but a comparison between the different lysozyme conditions using analysis of variance and post hoc tests did not reveal significant differences. In 10 wild strains, different patterns of biofilm formation on polystyrene were observed in the presence of lysozyme. Some strains, characterized by large amounts of biofilm formation in the presence of 1,000 µg/ml lysozyme, were poor biofilm producers at low concentrations of lysozyme. In contrast, some strains that were poor biofilm producers with a high lysozyme concentration were more inhibited by low concentrations of lysozyme. The present study emphasizes the need to develop strategies for biofilm control based on in vitro experiments, and to implement these in clinical trials prior to approval of hygiene products enriched with exocrine proteins, such as lysozyme. Further studies will extend these investigations to other Candida species, and to fungi

  11. Antiarthritic effect of lonicerin on Candida albicans arthritis in mice.

    PubMed

    Lee, Jue-Hee; Han, Yongmoon

    2011-05-01

    Fungal arthritis is a potentially serious disease resulting in rapid destruction of the joint. Among the various Candida species, Candida albicans is the most commonly associated with fungal arthritis. In the present study, we examined the effect of lonicerin, a flavonoid isolated from Lonicerae Flos, on an arthritis caused by C. albicans cell wall (CACW) in mice. To examine the effect, an emulsified mixture of CACW and complete Freund's adjuvant (CACW/CFA) was injected into BALB/c mice via hind footpad route on days -3, -2, and -1. On Day 0, mice with the swollen footpad received lonicerin at 1 or 2 mg/dose/time intraperitoneally 3 times every other day. The footpad-swelling was measured for 20 days. Results showed that the lonicerin treatment reduced the edema at all dose levels, and, furthermore, there was app. 54% edema reduction in animals given the 2 mg-dose at the peak (day 10) of septic arthritis (p < 0.05). Since the peak, the edema was reduced in similar rates. This antiarthritic activity appeared to be mediated by lonicerin's ability to suppress T cell proliferation, nitric oxide production from macrophages, and shift of cellular immunity from Th1- toward Th2-type responses, all of which are beneficial to treat arthritis. In addition, the flavonoid had anticandidal activity (p < 0.01). These data suggest that lonicerin alone, which has both anti-arthritic and antifungal activities, can result in a combination therapy for the treatment of fungal arthritis due to C. albicans infection.

  12. Kinetic and thermodynamic characterization of the interactions between the components of human plasma kinin-forming system and isolated and purified cell wall proteins of Candida albicans.

    PubMed

    Seweryn, Karolina; Karkowska-Kuleta, Justyna; Wolak, Natalia; Bochenska, Oliwia; Kedracka-Krok, Sylwia; Kozik, Andrzej; Rapala-Kozik, Maria

    2015-01-01

    Cell wall proteins of Candida albicans, besides their best known role in the adhesion of this fungal pathogen to host's tissues, also bind some soluble proteins, present in body fluids and involved in maintaining the biochemical homeostasis of the human organism. In particular, three plasma factors - high-molecular-mass kininogen (HK), factor XII (FXII) and prekallikrein (PPK) - have been shown to adhere to candidal cells. These proteins are involved in the surface-contact-catalyzed production of bradykinin-related peptides (kinins) that contribute to inflammatory states associated with microbial infections. We recently identified several proteins, associated with the candidal cell walls, and probably involved in the binding of HK. In our present study, a list of potential FXII- and PPK-binding proteins was proposed, using an affinity selection (on agarose-coupled FXII or PPK) from a whole mixture of β-1,3-glucanase-extrated cell wall-associated proteins and the mass-spectrometry protein identification. Five of these fungal proteins, including agglutinin-like sequence protein 3 (Als3), triosephosphate isomerase 1 (Tpi1), enolase 1 (Eno1), phosphoglycerate mutase 1 (Gpm1) and glucose-6-phosphate isomerase 1 (Gpi1), were purified and characterized in terms of affinities to the human contact factors, using the surface plasmon resonance measurements. Except Gpm1 that bound only PPK, and Als3 that exhibited an affinity to HK and FXII, the other isolated proteins interacted with all three contact factors. The determined dissociation constants for the identified protein complexes were of 10(-7) M order, and the association rate constants were in a range of 10(4)-10(5) M(-1)s(-1). The identified fungal pathogen-host protein interactions are potential targets for novel anticandidal therapeutic approaches.

  13. Regulation of phenotypic transitions in the fungal pathogen Candida albicans

    PubMed Central

    Huang, Guanghua

    2012-01-01

    The human commensal fungus Candida albicans can cause not only superficial infections, but also life-threatening disease in immunocompromised individuals. C. albicans can grow in several morphological forms. The ability to switch between different phenotypic forms has been thought to contribute to its virulence. The yeast-filamentous growth transition and white-opaque switching represent two typical morphological switching systems, which have been intensively studied in C. albicans. The interplay between environmental factors and genes determines the morphology of C. albicans. This review focuses on the regulation of phenotypic changes in this pathogenic organism by external environmental cues and internal genes. PMID:22546903

  14. 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

  15. In vitro activities of terbinafine in combination with fluconazole and itraconazole against isolates of Candida albicans with reduced susceptibility to azoles.

    PubMed Central

    Barchiesi, F; Falconi Di Francesco, L; Scalise, G

    1997-01-01

    A checkerboard microdilution method was applied to study the in vitro interaction of terbinafine with either fluconazole and itraconazole against 30 strains of Candida albicans. Synergy was observed in 40% of the terbinafine-fluconazole interactions and in 43% of the terbinafine-itraconazole interactions, while antagonism was not observed. Even when only additivity was achieved, the combinations still showed beneficial effects since at least twofold reductions in the MICs of both drugs were found in 100% of the terbinafine-fluconazole interactions and in 76% of the terbinafine-itraconazole interactions. PMID:9257768

  16. Rapid identification of Candida albicans by using Albicans ID and fluoroplate agar plates.

    PubMed Central

    Rousselle, P; Freydiere, A M; Couillerot, P J; de Montclos, H; Gille, Y

    1994-01-01

    Two commercially available agar media, Albicans ID and Fluoroplate, that use a chromogenic or a fluorogenic substrate for the detection and identification of Candida albicans were evaluated. From 1,006 clinical samples containing 723 yeast strains, 352 C. albicans strains were detected with either of the two media. The sensitivity of each of the two media was 93.8% and the specificity was 98.6%, with five false-positive reactions for Candida tropicalis and no false-negative reactions. PMID:7883894

  17. [DNA and RNA random amplification polymorphism in 5-flurocytosine-resistant strains of Candida albicans from revul-vaginal candidasis].

    PubMed

    Jiang, Xiu-xiu; Lu, Shi-ming

    2005-01-01

    To investigate the DNA genome and RNA expression in 5-flurocytosine-resistant strains of Candida albicans from vaginal candidasis. Sixteen strains of Candida albicans were selected from clinically diagnosed revul-vaginal candidasis. Eight 5-flurocytosine-sensitive isolates and 8 resistant isolates were examined by France Media FUNGUS sensitive test. DNA genome was detected with random amplification polymorph DNA. RNA expression was detected with random amplification polymorph RNA method. There were no distinct differences between 5-flurocytosine-sensitive and resistant Candida albicans in DNA genome, while RNA expression showed significant differences between 5-flurocytosine-resistant and sensitive strains. Clinical 5-flurocytosine-resistant strains of Candida albicans from revul-vaginal candidasis may be related to phenotype changes.

  18. 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

  19. 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

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

    PubMed

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

    2006-01-03

    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. 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. 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. 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.

  1. Liposomal thymoquinone effectively combats fluconazole-resistant Candida albicans in a murine model.

    PubMed

    Khan, Masood Alam; Aljarbou, Ahmad N; Khan, Arif; Younus, Hina

    2015-05-01

    The aim of the present study was to develop a novel liposomal formulation of thymoquinone (TQ) to treat fluconazole-susceptible and -resistant Candida albicans (C. albicans) infections. The liposomal preparation of TQ (Lip-TQ) was used against a fluconazole-susceptible or -resistant isolate of C. albicans. Various doses of fluconazole (0, 5, 10, 20 and 40 mg/kg) or free TQ or Lip-TQ (0, 1, 2 and 5mg/kg) were used to treat C. albicans infected mice. Mice were observed for 40 days post C. albicans infection, and their kidneys were assessed for the fungal load. Fluconazole showed anti-fungal activity against the drug-susceptible, but not against the -resistant isolate of C. albicans. Free TQ showed its activity against both fluconazole-susceptible or -resistant C. albicans, however, Lip-TQ was found to be the most effective and imparted ∼ 100% and ∼ 90% survival of mice infected with fluconazole-susceptible and -resistant isolates of C. albicans, respectively. Mice treated with Lip-TQ showed highly reduced severity of infection in their tissue homogenates. Therefore, Lip-TQ may effectively be used in the treatment of C. albicans infections, including those which are not responding to fluconazole.

  2. [The prevalence of Candida albicans and its relationship with early childhood caries among children of Uygur and Han nationalities in Kashi city].

    PubMed

    Zhang, Wanting; Lian, Bingjie; Zhao, Jin

    2016-05-01

    To explore the relationship between the prevalence of Candida albicans and early childhood caries(ECC) among 3-5 years old children of Uygur and Han nationalities in Kashi city, Xinjiang province. Totally 397 generally healthy children(Uyghurs 256, Hans141) aged 3-5 years were recruited randomly in Kashi city using the stratified cluster random method. Dental plaque samples were collected from carious tooth tissues of children with ECC and from supragingival tooth sites of caries free(CF) children, respectively. Plaque samples were cultured and Candida albicans were isolated selectively by using CHROM agar candida medium. The isolates were further identified using methods of germ tubes test, Gram stain and PCR molecular biology. The data were analyzed using Pearson χ(2) test and Spearman analysis. The prevalenses of Candida albicans were 44.5% (114/256) in Han children and 31.2%(44/141) in Urgur children, respectively(P=0.009). Candida albicans could be isolated from 48.8% (124/254) of ECC children, while 23.8% (34/143) of CF ones(P=0.000). The frequencies of Candida albicans acquisition of boys and girls of Uygur children were 51.2%(66/129) and 37.8%(48/127), respectively (P=0.031). The frequencies of Candida albicans acquisition increased with the decayed missing filled tooth (dmft) scores. For both Uygur and Hanchildren, the detection rates of Candida albicans were correlated with dmft scores(Uygur r=0.350, P=0.001; Han r=0.276, P=0.000). The oral Candida albicans distributions were different in Uygur and Han ethnic groups. There were significant correlations between the presence of Candida albicans and ECC severityas well as score of dmft. There was a difference of the Candida albicans distributions between boys and girls among Uygur children. Candida albicans might be one of the important cariogenic microorganisms in ECC.

  3. 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

  4. Candida dubliniensis and Candida albicans differentiation by colony morphotype in Sabouraud-triphenyltetrazolium agar.

    PubMed

    Gamarra, Soledad; Mancilla, Estefanía; Dudiuk, Catiana; Garcia-Effron, Guillermo

    2015-01-01

    Candida dubliniensis is a germ tube and chlamydoconidia producing Candida species that may be misidentified as Candida albicans. Molecular-based methods are the most reliable techniques for C. albicans and C. dubliniensis differentiation. However, accurate, quick and inexpensive phenotypic tests are needed to be used in low-complexity mycology laboratories. To evaluate colony morphotypes on Sabouraud-triphenyltetrazolium agar as a tool for C. dubliniensis and C. albicans differentiation. The morphology of 126 C. albicans and C. dubliniensis strains was evaluated and compared with their identification by molecular methods. The method showed 100% sensitivity and specificity when color and the presence or absence of large white mycelial halo was evaluated. Colony morphotype on Sabouraud-triphenyltetrazolium agar should be considered as a new tool to differentiate C. dubliniensis and C. albicans. Copyright © 2013 Revista Iberoamericana de Micología. Published by Elsevier Espana. All rights reserved.

  5. Differential adherence and expression of virulence traits by Candida albicans and Candida parapsilosis in mono- and dual-species cultures in artificial saliva.

    PubMed

    Seabra, C L; Botelho, C M; Henriques, M; Oliveira, R

    2013-08-01

    To evaluate specific virulence factors of Candida albicans and Candida parapsilosis clinical oral isolates in mono- and dual-species culture in the presence of artificial saliva. Two of the strains used in this study were isolated from co-infection (C. albicans AM and C. parapsilosis AM2), and the other two were isolated from single infection (C. albicans AC and C. parapsilosis AD). The number of adhered yeast cells was measured and their enzymatic activity was determined simultaneously. In mono-species culture, C. parapsilosis strains adhered to a higher extent to the surface in comparison with the C. albicans strains. In dual-species culture, the C. parapsilosis strains adhered more in the presence of C. albicans AM. Interestingly, C. albicans AM and C. parapsilosis AD adhered to a higher extent when compared with all other co-cultures. In dual-species culture, the enzymatic activity of C. parapsilosis strains in the presence of C. albicans AC was higher than in the presence of C. albicans AM. The virulence factors of C. albicans and C. parapsilosis differ from strain to strain and are influenced by the presence of other species in culture. To understand the expression of virulence factors in Candida dual-species systems.

  6. Hsp21 Potentiates Antifungal Drug Tolerance in Candida albicans

    PubMed Central

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

    2013-01-01

    Systemic infections of humans with the fungal pathogen Candida albicans are associated with a high mortality rate. Currently, efficient treatment of these infections is hampered by the relatively low number of available antifungal drugs. We recently identified the small heat shock protein Hsp21 in C. albicans and demonstrated its fundamental role for environmental stress adaptation and fungal virulence. Hsp21 was found in several pathogenic Candida species but not in humans. This prompted us to investigate the effects of a broad range of different antifungal drugs on an Hsp21-null C. albicans mutant strain. Our results indicate that combinatorial therapy targeting Hsp21, together with specific antifungal drug targets, has strong synergistic potential. In addition, we demonstrate that Hsp21 is required for tolerance to ethanol-induced stress and induction of filamentation in response to pharmacological inhibition of Hsp90. These findings might pave the way for the development of new treatment strategies against Candida infections. PMID:23533680

  7. Innate immune cell response upon Candida albicans infection

    PubMed Central

    Qin, Yulin; Zhang, Lulu; Xu, Zheng; Zhang, Jinyu; Jiang, Yuan-ying; Cao, Yongbing; Yan, Tianhua

    2016-01-01

    abstract 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. PMID:27078171

  8. 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.

  9. Candida albicans adherence to resin-composite restorative dental material: influence of whole human saliva.

    PubMed

    Maza, José Luis; Elguezabal, Natalia; Prado, Carlota; Ellacuría, Joseba; Soler, Iñaki; Pontón, José

    2002-11-01

    Attachment of Candida albicans to oral surfaces is believed to be a critical event in the colonization of the oral cavity and in the development of oral diseases such as Candida-associated denture stomatitis. Although there is considerable information about the adhesion of C albicans to buccal epithelial cells and prosthetic materials, there is very little information about the adhesion of C albicans to composite restorative materials. The purpose of this study was to investigate the degree of adhesion of C albicans to a resin-composite restorative material (Herculite). The adhesion of 2 strains of C albicans, a germinative and a germ tube-deficient mutant, was studied by a visual method after incubating the fungus and the resin with and without human whole saliva. In absence of saliva, the adhesion of the C albicans germinative isolate to the resin showed an increase in parallel with the germination, reaching a maximum at the end of the experiment (120 minutes). However, no significant differences were observed in the adhesion of the agerminative mutant during the period of time studied. In the presence of saliva, the adhesion of both isolates to the resin was significantly lowered. Germination and the presence of human whole saliva are important factors in the adhesion of C albicans to the resin-composite restorative material Herculite.

  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. Systemic Staphylococcus aureus infection mediated by Candida albicans hyphal invasion of mucosal tissue

    PubMed Central

    Schlecht, Lisa Marie; Peters, Brian M.; Krom, Bastiaan P.; Freiberg, Jeffrey A.; Hänsch, Gertrud M.; Filler, Scott G.

    2015-01-01

    Candida albicans and Staphylococcus aureus are often co-isolated in cases of biofilm-associated infections. C. albicans can cause systemic disease through morphological switch from the rounded yeast to the invasive hyphal form. Alternatively, systemic S. aureus infections arise from seeding through breaks in host epithelial layers although many patients have no documented portal of entry. We describe a novel strategy by which S. aureus is able to invade host tissue and disseminate via adherence to the invasive hyphal elements of Candida albicans. In vitro and ex vivo findings demonstrate a specific binding of the staphylococci to the candida hyphal elements. The C. albicans cell wall adhesin Als3p binds to multiple staphylococcal adhesins. Furthermore, Als3p is required for C. albicans to transport S. aureus into the tissue and cause a disseminated infection in an oral co-colonization model. These findings suggest that C. albicans can facilitate the invasion of S. aureus across mucosal barriers, leading to systemic infection in co-colonized patients. PMID:25332378

  12. 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.

  13. Global Identification of Biofilm-Specific Proteolysis in Candida albicans.

    PubMed

    Winter, Michael B; Salcedo, Eugenia C; Lohse, Matthew B; Hartooni, Nairi; Gulati, Megha; Sanchez, Hiram; Takagi, Julie; Hube, Bernhard; Andes, David R; Johnson, Alexander D; Craik, Charles S; Nobile, Clarissa J

    2016-09-13

    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. Biofilm formation by the opportunistic fungal pathogen C. albicans is a major cause of life-threatening infections. This work provides a global characterization of secreted proteolytic activity produced specifically by C. albicans biofilms. We identify activity from the proteases Sap5 and Sap6 as highly upregulated during C. albicans biofilm formation and develop Sap-cleavable fluorogenic substrates that enable the detection of biofilms from C. albicans and also

  14. Direct isolation of Candida spp. from blood cultures on the chromogenic medium CHROMagar Candida.

    PubMed

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

    2003-06-01

    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 degrees 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.

  15. 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

  16. 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.

  17. 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

  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. Candida krusei and Candida glabrata reduce the filamentation of Candida albicans by downregulating expression of HWP1 gene.

    PubMed

    de Barros, Patrícia Pimentel; Freire, Fernanda; Rossoni, Rodnei Dennis; Junqueira, Juliana Campos; Jorge, Antonio Olavo Cardoso

    2017-07-01

    Pathogenicity of Candida albicans is associated with its capacity switch from yeast-like to hyphal growth. The hyphal form is capable to penetrate the epithelial surfaces and to damage the host tissues. Therefore, many investigations have focused on mechanisms that control the morphological transitions of C. albicans. Recently, certain studies have showed that non-albicans Candida species can reduce the capacity of C. albicans to form biofilms and to develop candidiasis in animal models. Then, the objective of this study was to evaluate the effects of Candida krusei and Candida glabrata on the morphogenesis of C. albicans. Firstly, the capacity of reference and clinical strains of C. albicans in forming hyphae was tested in vitro. After that, the expression of HWP1 (hyphal wall protein 1) gene was determined by quantitative real-time PCR (polymerase chain reaction) assay. For both reference and clinical strains, a significant inhibition of the hyphae formation was observed when C. albicans was incubated in the presence of C. krusei or C. glabrata compared to the control group composed only by C. albicans. In addition, the culture mixed of C. albicans-C. krusei or C. albicans-C. glabrata reduced significantly the expression of HWP1 gene of C. albicans in relation to single cultures of this specie. In both filamentation and gene expression assays, C. krusei showed the higher inhibitory activity on the morphogenesis of C. albicans compared to C. glabrata. C. krusei and C. glabrata are capable to reduce the filamentation of C. albicans and consequently decrease the expression of the HWP1 gene.

  20. Comparative adherence of Candida albicans and Candida dubliniensis to human buccal epithelial cells and extracellular matrix proteins.

    PubMed

    Jordan, Rachael P C; Williams, David W; Moran, Gary P; Coleman, David C; Sullivan, Derek J

    2014-04-01

    Candida albicans and Candida dubliniensis are very closely related pathogenic yeast species. Despite their close relationship, C. albicans is a far more successful colonizer and pathogen of humans. The purpose of this study was to determine if the disparity in the virulence of the two species is attributed to differences in their ability to adhere to human buccal epithelial cells (BECs) and/or extracellular matrix proteins. When grown overnight at 30°C in yeast extract peptone dextrose, genotype 1 C. dubliniensis isolates were found to be significantly more adherent to human BECs than C. albicans or C. dubliniensis genotypes 2-4 (P < 0.001). However, when the yeast cells were grown at 37°C, no significant difference between the adhesion of C. dubliniensis genotype 1 and C. albicans to human BECs was observed, and C. dubliniensis genotype 1 and C. albicans adhered to BECs in significantly greater numbers than the other C. dubliniensis genotypes (P < 0.001). Using surface plasmon resonance analysis, C. dubliniensis isolates were found to adhere in significantly greater numbers than C. albicans to type I and IV collagen, fibronectin, laminin, vitronectin, and proline-rich peptides. These data suggest that C. albicans is not more adherent to epithelial cells or matrix proteins than C. dubliniensis and therefore other factors must contribute to the greater levels of virulence exhibited by C. albicans.

  1. Sensitivity of Candida albicans to essential oils: are they an alternative to antifungal agents?

    PubMed

    Bona, E; Cantamessa, S; Pavan, M; Novello, G; Massa, N; Rocchetti, A; Berta, G; Gamalero, E

    2016-12-01

    Candida albicans is an important opportunistic pathogen, responsible for the majority of yeast infections in humans. Essential oils, extracted from aromatic plants, are well-known antimicrobial agents, characterized by a broad spectrum of activities, including antifungal properties. The aim of this work was to assess the sensitivity of 30 different vaginal isolated strains of C. albicans to 12 essential oils, compared to the three main used drugs (clotrimazole, fluconazole and itraconazole). Thirty strains of C. albicans were isolated from vaginal swab on CHROMagar(™) Candida. The agar disc diffusion method was employed to determine the sensitivity to the essential oils. The antifungal activity of the essential oils and antifungal drugs (clotrimazole, itraconazole and fluconazole) were investigated using a microdilution method. Transmission and scanning electron microscopy analyses were performed to get a deep inside on cellular damages. Mint, basil, lavender, tea tree oil, winter savory and oregano essential oils inhibited both the growth and the activity of C. albicans more efficiently than clotrimazole. Damages induced by essential oils at the cellular level were stronger than those caused by clotrimazole. Candida albicans is more sensitive to different essential oils compared to the main used drugs. Moreover, the essential oil affected mainly the cell wall and the membranes of the yeast. The results of this work support the research for new alternatives or complementary therapies against vaginal candidiasis. © 2016 The Society for Applied Microbiology.

  2. Interspecies Interactions between Clostridium difficile and Candida albicans

    PubMed Central

    van Leeuwen, Pim T.; van der Peet, Jasper M.; Bikker, Floris J.; Hoogenkamp, Michel A.; Oliveira Paiva, Ana M.; Kostidis, Sarantos; Mayboroda, Oleg A.

    2016-01-01

    ABSTRACT The facultative anaerobic polymorphic fungus Candida albicans and the strictly anaerobic Gram-positive bacterium Clostridium difficile are two opportunistic pathogens residing in the human gut. While a few studies have focused on the prevalence of C. albicans in C. difficile-infected patients, the nature of the interactions between these two microbes has not been studied thus far. In the current study, both chemical and physical interactions between C. albicans and C. difficile were investigated. In the presence of C. albicans, C. difficile was able to grow under aerobic, normally toxic, conditions. This phenomenon was neither linked to adherence of bacteria to hyphae nor to biofilm formation by C. albicans. Conditioned medium of C. difficile inhibited hyphal growth of C. albicans, which is an important virulence factor of the fungus. In addition, it induced hypha-to-yeast conversion. p-Cresol, a fermentation product of tyrosine produced by C. difficile, also induced morphological effects and was identified as an active component of the conditioned medium. This study shows that in the presence of C. albicans, C. difficile can persist and grow under aerobic conditions. Furthermore, p-cresol, produced by C. difficile, is involved in inhibiting hypha formation of C. albicans, directly affecting the biofilm formation and virulence of C. albicans. This study is the first detailed characterization of the interactions between these two gut pathogens. IMPORTANCE Candida albicans and Clostridium difficile are two opportunistic pathogens that reside in the human gut. A few studies have focused on the prevalence of C. albicans in C. difficile-infected patients, but none have shown the interaction(s) that these two organisms may or may not have with each other. In this study, we used a wide range of different techniques to better understand this interaction at a macroscopic and microscopic level. We found that in the presence of C. albicans, C

  3. 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

  4. Dissecting Candida albicans Infection from the Perspective of C. albicans Virulence and Omics Approaches on Host-Pathogen Interaction: A Review.

    PubMed

    Chin, Voon Kin; Lee, Tze Yan; Rusliza, Basir; Chong, Pei Pei

    2016-10-18

    Candida bloodstream infections remain the most frequent life-threatening fungal disease, with Candida albicans accounting for 70% to 80% of the Candida isolates recovered from infected patients. In nature, Candida species are part of the normal commensal flora in mammalian hosts. However, they can transform into pathogens once the host immune system is weakened or breached. More recently, mortality attributed to Candida infections has continued to increase due to both inherent and acquired drug resistance in Candida, the inefficacy of the available antifungal drugs, tedious diagnostic procedures, and a rising number of immunocompromised patients. Adoption of animal models, viz. minihosts, mice, and zebrafish, has brought us closer to unraveling the pathogenesis and complexity of Candida infection in human hosts, leading towards the discovery of biomarkers and identification of potential therapeutic agents. In addition, the advancement of omics technologies offers a holistic view of the Candida-host interaction in a non-targeted and non-biased manner. Hence, in this review, we seek to summarize past and present milestone findings on C. albicans virulence, adoption of animal models in the study of C. albicans infection, and the application of omics technologies in the study of Candida-host interaction. A profound understanding of the interaction between host defense and pathogenesis is imperative for better design of novel immunotherapeutic strategies in future.

  5. The correlation of virulence, pathogenicity, and itraconazole resistance with SAP activity in Candida albicans strains.

    PubMed

    Feng, Wenli; Yang, Jing; Pan, Yanwei; Xi, Zhiqin; Qiao, Zusha; Ma, Yan

    2016-02-01

    The relationship between SAP2 activity and drug resistance in Candida albicans was investigated by using itraconazole-resistant and itraconazole-sensitive C. albicans isolates. The precipitation zones were measured to analyze SAP2 activity. Mice were classified into itraconazole-resistant and -sensitive C. albicans isolate groups, and a control group, with their survival and mortality rate being observed over 30 days. The relative expression levels of CDR1, CDR2, MDR1, and SAP2 were measured using RT-PCR. It was found that the secreted aspartyl proteinase activity of itraconazole-resistant C. albicans strains was significantly higher than that of itraconazole-sensitive C. albicans strains (P < 0.001). A significantly higher mortality rate was recorded for mice treated with itraconazole-resistant C. albicans than for mice treated with itraconazole-sensitive C. albicans. In regards to the CDR1, CDR2, and MDR1 genes, there was no significant difference between the 2 groups of mice. Positive correlations between SAP2 and MDR1 and between CDR1 and CDR2 were found. The high expression level of SAP2 may relate to the virulence, pathogenicity, and resistance of C. albicans.

  6. [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.

  7. Genotyping and Persistence of Candida albicans from Pregnant Women with Vulvovaginal Candidiasis.

    PubMed

    Tapia, Cecilia V; Hermosilla, Germán; Fortes, Paula; Alburquenque, Claudio; Bucarey, Sergio; Salinas, Hugo; Rodas, Paula I; Díaz, María Cristina; Magne, Fabien

    2017-04-01

    To study Candida albicans genotypes using RAPD and their susceptibility to fluconazole in healthy pregnant women and in vulvovaginal candidiasis (VVC) patients after topical treatment with clotrimazole. Vaginal swabs were collected at t = 0 and t = 1 (1 month later) in pregnant women (control group, n = 33), and before (t = 0), at 1 month (t = 1) and at 2 months (t = 2) after clotrimazole treatment in pregnant women with VVC. Candida albicans was isolated in 30% of healthy pregnant women and 80% of patients with VVC. A high genetic heterogeneity was observed in C. albicans genotypes between individuals. In patients with VVC, topical antifungal treatment with clotrimazole was clinically effective, but only in a 62% C. albicans was eradicated. In patients in which C. albicans was not eradicated, this microorganism persisted for 1 or 2 months after the antifungal treatment. The persistent colonies were not associated with a specific genotype, but they were associated with higher MICs in comparison with colonies isolated from the control group. Therapy with topical clotrimazole, despite a good clinical outcome, could not eradicate completely C. albicans allowing the persistence of genotypes, with higher MICs to fluconazole. More studies with higher number of patients are needed to validate this preliminary finding.

  8. An Optimized Lock Solution Containing Micafungin, Ethanol and Doxycycline Inhibits Candida albicans and Mixed C. albicans – Staphyloccoccus aureus Biofilms

    PubMed Central

    Lown, Livia; Peters, Brian M.; Walraven, Carla J.; Noverr, Mairi C.; Lee, Samuel A.

    2016-01-01

    Candida albicans is a major cause of catheter-related bloodstream infections and is associated with high morbidity and mortality. Due to the propensity of C. albicans to form drug-resistant biofilms, the current standard of care includes catheter removal; however, reinsertion may be technically challenging or risky. Prolonged exposure of an antifungal lock solution within the catheter in conjunction with systemic therapy has been experimentally attempted for catheter salvage. Previously, we demonstrated excellent in vitro activity of micafungin, ethanol, and high-dose doxycycline as single agents for prevention and treatment of C. albicans biofilms. Thus, we sought to investigate optimal combinations of micafungin, ethanol, and/or doxycycline as a lock solution. We performed two- and three-drug checkerboard assays to determine the in vitro activity of pairwise or three agents in combination for prevention or treatment of C. albicans biofilms. Optimal lock solutions were tested for activity against C. albicans clinical isolates, reference strains and polymicrobial C. albicans-S. aureus biofilms. A solution containing 20% (v/v) ethanol, 0.01565 μg/mL micafungin, and 800 μg/mL doxycycline demonstrated a reduction of 98% metabolic activity and no fungal regrowth when used to prevent fungal biofilm formation; however there was no advantage over 20% ethanol alone. This solution was also successful in inhibiting the regrowth of C. albicans from mature polymicrobial biofilms, although it was not fully bactericidal. Solutions containing 5% ethanol with low concentrations of micafungin and doxycycline demonstrated synergistic activity when used to prevent monomicrobial C. albicans biofilm formation. A combined solution of micafungin, ethanol and doxycycline is highly effective for the prevention of C. albicans biofilm formation but did not demonstrate an advantage over 20% ethanol alone in these studies. PMID:27428310

  9. Terpenoids inhibit Candida albicans growth by affecting membrane integrity and arrest of cell cycle.

    PubMed

    Zore, Gajanan B; Thakre, Archana D; Jadhav, Sitaram; Karuppayil, S Mohan

    2011-10-15

    Anti-Candida potential of six terpenoids were evaluated in this study against various isolates of Candida albicans (n=39) and non-C. albicans (n=9) that are differentially susceptible to fluconazole. All the six terpenoids tested, showed excellent activity and were equally effective against isolates of Candida sps., tested in this study. Linalool and citral were the most effective ones, inhibiting all the isolates at ≤0.064% (v/v). Five among the six terpenoids tested were fungicidal. Time dependent kill curve assay showed that MFCs of linalool and eugenol were highly toxic to C. albicans, killing 99.9% inoculum within seven min of exposure, while that of citronellal, linalyl acetate and citral required 15min, 1h and 2h, respectively. FIC index values (Linalool - 0.140, benzyl benzoate - 0.156, eugenol - 0.265, citral - 0.281 and 0.312 for linalyl acetate and citronellal) and isobologram obtained by checker board assay showed that all the six terpenoids tested exhibit excellent synergistic activity with fluconazole against a fluconazole resistant strain of C. albicans. Terpenoids tested arrested C. albicans cells at different phases of the cell cycle i.e. linalool and LA at G1, citral and citronellal at S phase and benzyl benzoate at G2-M phase and induced apoptosis. Linalool, citral, citronellal and benzyl benzoate caused more than 50% inhibition of germ tube induction at 0.008%, while eugenol and LA required 0.032 and 0.016% (v/v) concentrations, respectively. MICs of all the terpenoids for the C. albicans growth were non toxic to HeLa cells. Terpenoids tested exhibited excellent activity against C. albicans yeast and hyphal form growth at the concentrations that are non toxic to HeLa cells. Terpenoids tested in this study may find use in antifungal chemotherapy, not only as antifungal agents but also as synergistic agents along with conventional drugs like fluconazole.

  10. Prevalence of candida albicans in dental plaque and caries lesion of early childhood caries (ECC) according to sampling site

    PubMed Central

    Ghasempour, Maryam; Sefidgar, Seyed Ali Asghar; Eyzadian, Haniyeh; Gharakhani, Samaneh

    2011-01-01

    Background: Candida albicans may have cariogenic potential but its role in caries etiology has not been established. The aim of this study was to determine candida albicans in supragingival dental plaque and infected dentine of cervical and proximal in early childhood caries (ECC). Methods: This cross-sectional study was carried out on 6o children aged 2-5 years, which were divided into 3 groups: children with at least one cervical caries; children with at least one proximal caries and caries-free. The infected dentine was collected from cervical and proximal caries lesions and plaque samples were collected from the three groups in order to compare the frequency of candida albicans in the collected sites. All samples were cultured in Sabouraud and CHROMagar medium and the cases that were positive for candida albicans were cultured in germ tube. Data were collected and analyzed. Results: The mean age of the children was 3.9 years. From 100 samples, candida albicans samples were isolated in 55%, mold fungi were found in 29% cases and there was no fungal growth in 16% of the samples. In plaque samples, candida albicans were found in 15% of caries-free samples, 20% of the proximal and 80% of the cervical caries. In samples extracted from the caries, candida albicans were found in 60% of the proximal and 100% of the cervical caries. Mothers with university educational level had children with more cervical decays, caries free and proximal caries, respectively. Conclusion: The results showed that prevalence of Candida albicans in dental plaque and caries lesions of children with early childhood caries were relatively high and the prevalence was higher in cervical caries group. PMID:24551436

  11. [Cell biology of respiration-deficient mutants of Candida albicans].

    PubMed

    Aoki, Shigeji; Ito-Kuwa, Shoko; Nakamura, Kenjirou; Nakamura, Yasunori

    2005-01-01

    Respiration-deficient (petite) mutation is caused by hereditary impairment in mitochondrial functions. Yeasts have been grouped into "petite-positive" and "petite-negative" yeasts. Candida albicans has been regarded as a member of the petite-negative yeasts in which the respiration deficiency cannot be easily induced. We have succeeded in inducing the petite mutation in C. albicans by culturing in the presence of a chemical mutagen, acriflavine, at an elevated temperature. In the present review, we describe the cell biology of C. albicans petite mutants on the basis of experiments performed by our research group: namely, on respiratory activity and cytochrome composition, fine structures of cells and mitochondria, mitochondrial DNA structure, pathogenicity, oxidative stress sensitivity, generation of reactive oxygen species (ROS) and the roles of ROS in antifungal actions. We discuss also the usefulness of petite mutants in Candida research.

  12. 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

  13. 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.

  14. 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

  15. Baicalin prevents Candida albicans infections via increasing its apoptosis rate

    SciTech Connect

    Yang, Shulong; Fu, Yingyuan Wu, Xiuzhen; Zhou, Zhixing; Xu, Jing; Zeng, Xiaoping; Kuang, Nanzhen; Zeng, Yurong

    2014-08-15

    Highlights: • Baicalin increases the ratio of the G0/G1 stages and C. albicans apoptosis. • Baicalin decreases the proliferation index of C. albicans. • Baicalin inhibits the biosynthesis of DNA, RNA and protein in C. albicans. • Baicalin depresses Succinate Dehydrogenase and Ca{sup 2+}–Mg{sup 2+} ATPase in C. albicans. • Baicalin increases the endocytic free Ca{sup 2+} concentration in C. albicans. - Abstract: Background: These experiments were employed to explore the mechanisms underlying baicalin action on Candida albicans. Methodology and principal findings: We detected the baicalin inhibition effects on three isotope-labeled precursors of {sup 3}H-UdR, {sup 3}H-TdR and {sup 3}H-leucine incorporation into C. albicans using the isotope incorporation technology. The activities of Succinate Dehydrogenase (SDH), cytochrome oxidase (CCO) and Ca{sup 2+}–Mg{sup 2+} ATPase, cytosolic Ca{sup 2+} concentration, the cell cycle and apoptosis, as well as the ultrastructure of C.albicans were also tested. We found that baicalin inhibited {sup 3}H-UdR, {sup 3}H-TdR and {sup 3}H-leucine incorporation into C.albicans (P < 0.005). The activities of the SDH and Ca{sup 2+}–Mg{sup 2+} ATPase of C.albicans in baicalin groups were lower than those in control group (P < 0.05). Ca{sup 2+} concentrations of C. albicans in baicalin groups were much higher than those in control group (P < 0.05). The ratio of C.albicans at the G0/G1 stage increased in baicalin groups in dose dependent manner (P < 0.01). There were a significant differences in the apoptosis rate of C.albicans between baicalin and control groups (P < 0.01). After 12–48 h incubation with baicalin (1 mg/ml), C. albicans shown to be markedly damaged under transmission electron micrographs. Innovation and significance: Baicalin can increase the apoptosis rate of C. albicans. These effects of Baicalin may involved in its inhibiting the activities of the SDH and Ca{sup 2+}–Mg{sup 2+} ATPase, increasing

  16. 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

  17. FK520 interacts with the discrete intrahelical amino acids of multidrug transporter Cdr1 protein and acts as antagonist to selectively chemosensitize azole-resistant clinical isolates of Candida albicans.

    PubMed

    Nim, Shweta; Rawal, Manpreet K; Prasad, Rajendra

    2014-06-01

    FK520, a homolog of antifungal FK506, displays fungicidal synergism with azoles in Candida albicans and inhibits drug efflux mediated by ABC multidrug transporter. This study establishes the molecular basis of interaction of FK520 with Cdr1 protein, which is one of the major ABC multidrug transporters of C. albicans. For this, we have exploited an in-house library of Cdr1 protein consisting of 252 mutant variants where the entire primary structure of the two transmembrane domains comprising of 12 transmembrane helices was subjected to alanine scanning. With these mutant variants of Cdr1 protein, we could identify the critical amino acids of the transporter protein, which if replaced with alanine, not only abrogated FK520-dependent competitive inhibition of drug efflux but simultaneously decreased susceptibility to azoles. Notably, the replacement of most of the residues with alanine was inconsequential; however, there were close to 13% mutant variants, which showed abrogation of drug efflux and reversal of fungicidal synergy with azoles. Of note, all the intrahelical residues of Cdr1 protein, which abrogated inhibitor's ability to block the efflux and reversed fungicidal synergy, were common. Taken together, our results provide evidence of cross-talk of FK520 with Cdr1 by interacting with the select intrahelical residues of the protein to chemosensitize isolates of Candida.

  18. 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.

  19. 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

  20. Inhibition of Candida albicans virulence factors by novel levofloxacin derivatives.

    PubMed

    Shafreen, Raja Mohamed Beema; Raja Mohamed, Beema Shafreen; Muthamil, Subramanian; Subramanian, Muthamil; Pandian, Shunmugiah Karutha; Shunmugiah, Karutha Pandian

    2014-08-01

    Candida albicans is an important opportunistic fungal pathogen, responsible for biofilm associated infections in immunocompromised patients. The aim of the present study was to investigate the antibiofilm properties of novel levofloxacin derivatives on C. albicans biofilms. The levofloxacin derivatives at their Biofilm Inhibitory Concentrations (BIC) were able to inhibit the biofilms of C. albicans, the yeast-to-hyphal transition and were also able to disrupt their mature biofilms. Furthermore, Real-time PCR analysis showed that the expression of ergosterol biosynthesis pathway gene (ERG11) and the efflux pump-encoding genes (CDR1 and MDR1) was decreased upon treatment with the levofloxacin derivatives. The total ergosterol content quantified using UV spectrophotomer showed decrease in ergosterol in the presence of levofloxacin derivatives. Overall, levofloxacin derivatives (6a, 6c and 7d) are capable of inhibiting C. albicans virulence factors. Therefore, these compounds with potential therapeutic implications can be used as new strategy to treat biofilm-related candidal infections.

  1. Molecular genetic techniques for gene manipulation in Candida albicans

    PubMed Central

    Xu, Qiu-Rong; Yan, Lan; Lv, Quan-Zhen; Zhou, Mi; Sui, Xue; Cao, Yong-Bing; Jiang, Yuan-Ying

    2014-01-01

    Candida albicans is one of the most common fungal pathogen in humans due to its high frequency as an opportunistic and pathogenic fungus causing superficial as well as invasive infections in immunocompromised patients. An understanding of gene function in C. albicans is necessary to study the molecular basis of its pathogenesis, virulence and drug resistance. Several manipulation techniques have been used for investigation of gene function in C. albicans, including gene disruption, controlled gene expression, protein tagging, gene reintegration, and overexpression. In this review, the main cassettes containing selectable markers used for gene manipulation in C. albicans are summarized; the advantages and limitations of these cassettes are discussed concerning the influences on the target gene expression and the virulence of the mutant strains. PMID:24759671

  2. Short peptides allowing preferential detection of Candida albicans hyphae.

    PubMed

    Kaba, Hani E J; Pölderl, Antonia; Bilitewski, Ursula

    2015-09-01

    Whereas the detection of pathogens via recognition of surface structures by specific antibodies and various types of antibody mimics is frequently described, the applicability of short linear peptides as sensor molecules or diagnostic tools is less well-known. We selected peptides which were previously reported to bind to recombinant S. cerevisiae cells, expressing members of the C. albicans Agglutinin-Like-Sequence (ALS) cell wall protein family. We slightly modified amino acid sequences to evaluate peptide sequence properties influencing binding to C. albicans cells. Among the selected peptides, decamer peptides with an "AP"-N-terminus were superior to shorter peptides. The new decamer peptide FBP4 stained viable C. albicans cells more efficiently in their mature hyphal form than in their yeast form. Moreover, it allowed distinction of C. albicans from other related Candida spp. and could thus be the basis for the development of a useful tool for the diagnosis of invasive candidiasis.

  3. 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

  4. 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

  5. Dissecting Candida albicans Infection from the Perspective of C. albicans Virulence and Omics Approaches on Host–Pathogen Interaction: A Review

    PubMed Central

    Chin, Voon Kin; Lee, Tze Yan; Rusliza, Basir; Chong, Pei Pei

    2016-01-01

    Candida bloodstream infections remain the most frequent life-threatening fungal disease, with Candida albicans accounting for 70% to 80% of the Candida isolates recovered from infected patients. In nature, Candida species are part of the normal commensal flora in mammalian hosts. However, they can transform into pathogens once the host immune system is weakened or breached. More recently, mortality attributed to Candida infections has continued to increase due to both inherent and acquired drug resistance in Candida, the inefficacy of the available antifungal drugs, tedious diagnostic procedures, and a rising number of immunocompromised patients. Adoption of animal models, viz. minihosts, mice, and zebrafish, has brought us closer to unraveling the pathogenesis and complexity of Candida infection in human hosts, leading towards the discovery of biomarkers and identification of potential therapeutic agents. In addition, the advancement of omics technologies offers a holistic view of the Candida-host interaction in a non-targeted and non-biased manner. Hence, in this review, we seek to summarize past and present milestone findings on C. albicans virulence, adoption of animal models in the study of C. albicans infection, and the application of omics technologies in the study of Candida–host interaction. A profound understanding of the interaction between host defense and pathogenesis is imperative for better design of novel immunotherapeutic strategies in future. PMID:27763544

  6. 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.

  7. Candida albicans biofilm development under increased temperature.

    PubMed

    Pumeesat, Potjaman; Muangkaew, Watcharamat; Ampawong, Sumate; Luplertlop, Natthanej

    2017-08-21

    C. albicans is one of the most important species of fungi known to produce biofilms on installed medical devices. The environment surrounding the fungi influences the development of the biofilm. Temperature is known to affect the yeast-to-hypha transition of C. albicans, but the impact of this factor on biofilm formation is still not understood. This study aimed to investigate the effects of temperature (42 °C versus 37 °C) on the formation of C. albicans biofilms. Three reference C. albicans strains were used: SC 5314, ATCC 90028, and ATCC 96901. Biofilm development was monitored in a series of time intervals, 2, 4, 6, 8, 24, and 48 h, at both 37 °C and 42 °C. Biofilm formation under each condition was evaluated by scanning electron microscopy, crystal violet staining, and 2,3-bis (2-methoxy-4-nitro-5-sulfophenyl)-5-(phenylamino)-carbonyl-2H-tetrazoliumhydroxide reduction assay. Our results demonstrated that at 42 °C, tested strains of C. albicans could produce a biofilm, but the mass, thickness, and metabolic activity were lower than those of the biofilm formed at 37 °C.

  8. 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.

  9. Comparison Between Biofilm Production, Phospholipase and Haemolytic Activity of Different Species of Candida Isolated from Dental Caries Lesions in Children

    PubMed Central

    Shenoy, Neetha

    2016-01-01

    Introduction C.albicans is the most commonly isolated fungal pathogen in the oral cavity, but isolation of non-albicans Candida is increasing in recent years. We wish to demonstrate the virulence factors of Candida spp. isolated from the dental caries lesion of the children as presence of virulence factors determines the pathogenic potential of any microorganism. Aim To compare biofilm production, phospholipase and haemolytic activity of C.albicans with that of non-albicans species of Candida isolated from dental caries lesions of children to evaluate the role of non- albicans species of Candida in formation of dental caries. Materials and Methods Oral swabs were collected from caries lesion of 100 school children of age 5-10 years with dental caries. Candida isolates were tested for biofilm production, phospholipase and haemolytic activity. Statistical analysis was done by Chi-Square test and Mann-Whitney U test wherever applicable using SPSS version 11.5. Results Out of the 100 children with dental caries 37 were positive for Candida by smear or culture and 31 by culture. C.albicans was the most prevalent isolate followed by C.krusei, C.tropicalis and C.albicans. Out of 21 C.albicans isolates, 10 (47.6%) showed phospholipase activity and 18 (85.71%) produced biofilm. Of the 10 non-albicans strains, 5 (50%) showed phospholipase activity and 6 (60%) produced biofilm. All isolates of Candida produced haemolysin (100%). Conclusion There was no statistically relevant difference between the virulence factor production by C.albicans and non-albicans species of Candida. In other words, our study shows that both C.albicans and non-albicans species of Candida isolated from caries lesions of the children, produce these virulence factors. So we can say that non-albicans species of Candida also are involved in caries formation. PMID:27190803

  10. Impact of oxidative and osmotic stresses on Candida albicans biofilm formation.

    PubMed

    Pemmaraju, Suma C; Padmapriya, Kumar; Pruthi, Parul A; Prasad, R; Pruthi, Vikas

    2016-09-01

    Candida albicans possesses an ability to grow under different host-driven stress conditions by developing robust protective mechanisms. In this investigation the focus was on the impact of osmotic (2M NaCl) and oxidative (5 mM H2O2) stress conditions during C. albicans biofilm formation. Oxidative stress enhanced extracellular DNA secretion into the biofilm matrix, increased the chitin level, and reduced virulence factors, namely phospholipase and proteinase activity, while osmotic stress mainly increased extracellular proteinase and decreased phospholipase activity. Fourier transform infrared and nuclear magnetic resonance spectroscopy analysis of mannan isolated from the C. albicans biofilm cell wall revealed a decrease in mannan content and reduced β-linked mannose moieties under stress conditions. The results demonstrate that C. albicans adapts to oxidative and osmotic stress conditions by inducing biofilm formation with a rich exopolymeric matrix, modulating virulence factors as well as the cell wall composition for its survival in different host niches.

  11. Survival of Candida albicans in tropical marine and fresh waters.

    PubMed Central

    Valdes-Collazo, L; Schultz, A J; Hazen, T C

    1987-01-01

    A survey of Candida albicans indicated that the organism was present at all sites sampled in a rain forest stream and in near-shore coastal waters of Puerto Rico. In the rain forest watershed no relationship existed between densities of fecal coliforms and densities of C. albicans. At two pristine sites in the rain forest watershed both C. albicans and Escherichia coli survived in diffusion chambers for extended periods of time. In near-shore coastal waters C. albicans and E. coli survival times in diffusion chambers were enhanced by effluent from a rum distillery. The rum distillery effluent had a greater effect on E. coli than on C. albicans survival in the diffusion chambers. These studies show that neither E. coli nor C. albicans organisms are good indicators of recent fecal contamination in tropical waters. It further demonstrates that pristine freshwater environments and marine waters receiving organic loading in the tropics can support densities of C. albicans which may be a health hazard. Images PMID:3310885

  12. AI-2 of Aggregatibacter actinomycetemcomitans inhibits Candida albicans biofilm formation.

    PubMed

    Bachtiar, Endang W; Bachtiar, Boy M; Jarosz, Lucja M; Amir, Lisa R; Sunarto, Hari; Ganin, Hadas; Meijler, Michael M; Krom, Bastiaan P

    2014-01-01

    Aggregatibacter actinomycetemcomitans, a Gram-negative bacterium, and Candida albicans, a polymorphic fungus, are both commensals of the oral cavity but both are opportunistic pathogens that can cause oral diseases. A. actinomycetemcomitans produces a quorum-sensing molecule called autoinducer-2 (AI-2), synthesized by LuxS, that plays an important role in expression of virulence factors, in intra- but also in interspecies communication. The aim of this study was to investigate the role of AI-2 based signaling in the interactions between C. albicans and A. actinomycetemcomitans. A. actinomycetemcomitans adhered to C. albicans and inhibited biofilm formation by means of a molecule that was secreted during growth. C. albicans biofilm formation increased significantly when co-cultured with A. actinomycetemcomitans luxS, lacking AI-2 production. Addition of wild-type-derived spent medium or synthetic AI-2 to spent medium of the luxS strain, restored inhibition of C. albicans biofilm formation to wild-type levels. Addition of synthetic AI-2 significantly inhibited hypha formation of C. albicans possibly explaining the inhibition of biofilm formation. AI-2 of A. actinomycetemcomitans is synthesized by LuxS, accumulates during growth and inhibits C. albicans hypha- and biofilm formation. Identifying the molecular mechanisms underlying the interaction between bacteria and fungi may provide important insight into the balance within complex oral microbial communities.

  13. 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

  14. Integrating Candida albicans metabolism with biofilm heterogeneity by transcriptome mapping

    PubMed Central

    Rajendran, Ranjith; May, Ali; Sherry, Leighann; Kean, Ryan; Williams, Craig; Jones, Brian L.; Burgess, Karl V.; Heringa, Jaap; Abeln, Sanne; Brandt, Bernd W.; Munro, Carol A.; Ramage, Gordon

    2016-01-01

    Candida albicans biofilm formation is an important virulence factor in the pathogenesis of disease, a characteristic which has been shown to be heterogeneous in clinical isolates. Using an unbiased computational approach we investigated the central metabolic pathways driving biofilm heterogeneity. Transcripts from high (HBF) and low (LBF) biofilm forming isolates were analysed by RNA sequencing, with 6312 genes identified to be expressed in these two phenotypes. With a dedicated computational approach we identified and validated a significantly differentially expressed subnetwork of genes associated with these biofilm phenotypes. Our analysis revealed amino acid metabolism, such as arginine, proline, aspartate and glutamate metabolism, were predominantly upregulated in the HBF phenotype. On the contrary, purine, starch and sucrose metabolism was generally upregulated in the LBF phenotype. The aspartate aminotransferase gene AAT1 was found to be a common member of these amino acid pathways and significantly upregulated in the HBF phenotype. Pharmacological inhibition of AAT1 enzyme activity significantly reduced biofilm formation in a dose-dependent manner. Collectively, these findings provide evidence that biofilm phenotype is associated with differential regulation of metabolic pathways. Understanding and targeting such pathways, such as amino acid metabolism, is potentially useful for developing diagnostics and new antifungals to treat biofilm-based infections. PMID:27765942

  15. Integrating Candida albicans metabolism with biofilm heterogeneity by transcriptome mapping

    NASA Astrophysics Data System (ADS)

    Rajendran, Ranjith; May, Ali; Sherry, Leighann; Kean, Ryan; Williams, Craig; Jones, Brian L.; Burgess, Karl V.; Heringa, Jaap; Abeln, Sanne; Brandt, Bernd W.; Munro, Carol A.; Ramage, Gordon

    2016-10-01

    Candida albicans biofilm formation is an important virulence factor in the pathogenesis of disease, a characteristic which has been shown to be heterogeneous in clinical isolates. Using an unbiased computational approach we investigated the central metabolic pathways driving biofilm heterogeneity. Transcripts from high (HBF) and low (LBF) biofilm forming isolates were analysed by RNA sequencing, with 6312 genes identified to be expressed in these two phenotypes. With a dedicated computational approach we identified and validated a significantly differentially expressed subnetwork of genes associated with these biofilm phenotypes. Our analysis revealed amino acid metabolism, such as arginine, proline, aspartate and glutamate metabolism, were predominantly upregulated in the HBF phenotype. On the contrary, purine, starch and sucrose metabolism was generally upregulated in the LBF phenotype. The aspartate aminotransferase gene AAT1 was found to be a common member of these amino acid pathways and significantly upregulated in the HBF phenotype. Pharmacological inhibition of AAT1 enzyme activity significantly reduced biofilm formation in a dose-dependent manner. Collectively, these findings provide evidence that biofilm phenotype is associated with differential regulation of metabolic pathways. Understanding and targeting such pathways, such as amino acid metabolism, is potentially useful for developing diagnostics and new antifungals to treat biofilm-based infections.

  16. Molecular epidemiology of Candida albicans colonization and fungemia in very low birthweight infants

    PubMed Central

    Robinson, Joan L; Hartstein, Alan I; Meuser, Renate U; Morthland, Virginia H; Dragoon, Margaret E; Wenman, Wanda M

    1993-01-01

    Objective: This study investigated the relationship between colonization and fungemia. Design: This was a prospective study involving surveillance cultures of the nares, base of umbilicus, point of entry of umbilical catheter and parenteral fluids. Blood cultures were done when sepsis was suspected. All Candida albicans isolates were typed using restriction enzyme analysis of DNA. Setting: Patients were from the neonatal intensive care unit of a tertiary care hospital. Population Studied: Twenty-nine very low birthweight infants. Main Results: Eleven babies were colonized with C albicans and five of these babies developed fungemia, including five of seven who were colonized at the point of entry of the umbilical catheter. Three different strains of C albicans caused fungemia. In four of the five patients, initial catheter entry site isolates were identical to the subsequent blood isolates. Occasionally, infants were colonized with more than one strain of C albicans. Conclusions: Preceding colonization with C albicans and, in particular, colonization at the site of entry of umbilical vascular catheters are risk factors for subsequent development of C albicans fungemia. Fungemic and colonizing isolates are usually identical to one another by DNA typing. PMID:22346467

  17. ENDOTOXIN-INDUCED TOLERANCE TO TOXIC MANIFESTATIONS OF CANDIDA ALBICANS

    PubMed Central

    Hasenclever, H. F.; Mithcell, William O.

    1963-01-01

    Hasenclever, H. F. (National Institutes of Health, Bethesda, Md.) and William O. Mitchell. Endotoxin-induced tolerance to toxic manifestations of Candida albicans. J. Bacteriol. 85:1088–1093. 1963.—Mice exposed to 425 r total body irradiation failed to become tolerant to Candida albicans toxicity after injection with lipopolysaccharide. Mice injected with lipopolysaccharide and then X-rayed did not demonstrate the tolerant state. An injection of thorium dioxide in mice that had previously received tolerance-inducing amounts of lipopolysaccharide rendered them as susceptible to acute C. albicans toxicity as control mice. A bimodal manifestation of tolerance was noted. Groups of mice given single injections of lipopolysaccharide at 6 or 1 days before challenge demonstrated high levels of tolerance, whereas the tolerance in mice given a single dose at 3 days was negligible. The bimodal effect was not observed in tolerant mice challenged with lipopolysaccharide. Injections of viable or nonviable pathogenic fungi known to produce tolerance to the toxicity of C. albicans in recipient mice did not produce tolerance to lipopolysaccharide. Serum from mice injected with lipopolysaccharide showed in vitro inhibitory activity for C. albicans. PMID:14043999

  18. 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.

  19. SST broth, a new serum free germ tube induction medium for identification of Candida albicans.

    PubMed

    Raghunath, Pendru; Seshu Kumari, K; Subbannayya, K

    2014-07-01

    Three serum free media viz, sucrose solution, starch solution and SST broth have been formulated. The objective of the present study was to evaluate these three different serum free media for induction of germ tubes by Candida albicans and to compare their efficacy with the pooled human serum. Out of 50 C. albicans isolates 47 (94%) and 49 (98%) produced germ tubes in pooled human serum and SST broth, respectively. Germ tube production was positive in 40 (80%) and 36 (72%) isolates, respectively in sucrose solution and starch solution. This study reports SST broth as a new stable and less expensive germ tube induction medium, which requires less time for preparation and can be used without any safety concerns. SST broth is found to be more effective than pooled human serum for induction of germ tubes by C. albicans isolates.

  20. 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.

  1. 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.

  2. Hemin induces germ tube formation in Candida albicans.

    PubMed Central

    Casanova, M; Cervera, A M; Gozalbo, D; Martínez, J P

    1997-01-01

    Hemin induced germination of Candida albicans blastoconidia when cells grown up to the early exponential phase were shifted from 28 to 37 degrees C (70 to 75% of cells exhibited germ tubes). N-Acetyl-D-glucosamine (GlcNAc), another inducer of myceliation in this fungus, caused a similar effect. The combination of hemin and GlcNAc resulted in a higher percentage (95%) of blastoconidial germination. These results suggest that in addition to temperature, hemin levels and carbon source may coordinately regulate the expression of subsets of genes involved in the yeast-to-mycelium transition in C. albicans. PMID:9317050

  3. Improved medium for fluconazole susceptibility testing of Candida albicans.

    PubMed Central

    Rodriguez-Tudela, J L; Martinez-Suarez, J V

    1994-01-01

    We have compared fluconazole susceptibilities of 92 clinical isolates of Candida albicans by broth microdilution in two different media: standard RPMI 1640 (RPMI) and the same medium supplemented with 18 g of glucose per liter (RPMI-glucose). Preparation of media, drugs, and inocula, as well as incubation conditions, followed the preliminary recommendations of the National Committee for Clinical Laboratory Standards (Villanova, Pa.) antifungal agent working group for broth macrodilution tests with antifungal agents, adapted to microdilution. Microtiter plates were agitated for 5 min before spectrophotometric readings were performed with an automatic plate reader set at 405 mm. The MIC endpoint was defined as an inhibitory concentration calculated from the turbidimetric data as a function of the turbidity in the drug-free control wells. The mean absorbances in the drug-free wells in RPMI and RPMI-glucose were, respectively, 0.38 (41.6% transmission) and 0.99 (10.2% transmission) (P < 0.001; Student's t test). Despite the increased growth in RPMI-glucose, 98.9% of the C. albicans strains tested for fluconazole susceptibility yielded similar MICs (+/- 1 dilution) in both media. Moreover, strains with decreased susceptibility to fluconazole displaying similar MICs in both media are easier to detect in RPMI-glucose because of the greater differences between turbidimetric readings in wells with grown or fluconazole-inhibited cultures. This objective turbidimetric method, with an easy-to-read improved medium (RPMI with glucose), together with previous experience of the National Committee for Clinical Laboratory Standards antifungal agent subcommittee, could overcome some of the present problems associated with lack of reproducibility of azole susceptibility testing. PMID:8141578

  4. [25S rDNA genotype and antifungal susceptibility of vaginal Candida albicans].

    PubMed

    Zhang, X; Liu, Z H

    2016-04-25

    To investigate 25S rDNA genotype distribution of vaginal Candida albicans and its relationship with antifungal susceptibility. A total of 954 isolates of Candida albicans were subjected to genotype analysis according to the presence and the size of transposable group Ⅰ intron in 25S rDNA with PCR; 156 isolates were enrolled to detect their antifungal susceptibility of 5 antifungal agents with the M27-A3 broth microdilution method. Totally 876 isolates were determined to be intronless genotype A(91.8%, 876/954); 58(6.1%, 58/954)and 20 isolates(2.1%, 20/954)were introncontaining genotype B and genotype C, respectively. The minimal inhibitory concentrations(MIC)of itraconazole and fluconazole against the intron-containing group were significantly higher than those of the intronless group(0.25 versus 0.125 μg/ml, P<0.05; 0.25 versus 0.125 μg/ml, P<0.01), whereas the MIC of nystatin against the intron-containing group was lower than that of the intronless group(4 versus 8 μg/ml, P< 0.01). The resistance rate of Candida albicans to itraconazole of the intron-containing group was significantly higher than that of the intronless group[24%(19/78)versus 3%(2/78), P<0.01]. Cross-resistance analysis revealed 5 of the 21(24%)itraconazole resistant isolates were cross-resistant to fluconazole , and 5 of the 6(5/6)fluconazole-resistant strains were cross-resistant to itraconazole. Besides, all the five strains simultaneously resistant to itraconazole and fluconazole belonged to the intron-containing group. The presence of the transposable group Ⅰ intron in 25S rDNA of vaginal Candida albicans might be important in affecting itraconazole, fluconazole and nystatin susceptibility.

  5. Evaluation of Mueller-Hinton-agar as a simple medium for the germ tube production of Candida albicans and Candida dubliniensis.

    PubMed

    Rimek, Dagmar; Fehse, Brigitte; Göpel, Petra

    2008-05-01

    Candida albicans is the most frequently isolated yeast species from clinical specimens. A classical rapid presumptive differentiation from non-albicans species is based on its ability to produce germ tubes after incubation in human serum. The only non-albicans Candida species producing germ tubes is Candida dubliniensis. In this study, we evaluated Mueller-Hinton-agar (MH-agar) as a medium for germ tube formation of C. albicans and C. dubliniensis. A total of 859 yeast isolates from stool samples, including 632 strains of C. albicans, 10 C. dubliniensis and 217 other yeast strains from 20 different species, were grown on Sabouraud glucose (2%) agar at 37 degrees C for 24-72 h. Species were identified by standard methods. For the germ tube test (GTT), an inoculum from a single colony was streaked onto a MH-agar plate and covered by a sterile coverslip. After incubation at 37 degrees C for 2 h, the MH plates were examined using a light microscope at x200. The GTT was positive in 578 of 632 C. albicans strains (sensitivity 91.5%), in six of 10 C. dubliniensis strains (sensitivity 60.0%), and in none of the other yeast strains. MH-agar is a suitable medium for the GTT and the presumptive identification of C. albicans. It is safer to use than human serum and is widely available in microbiology laboratories.

  6. Candida albicans, Staphylococcus aureus and Streptococcus mutans colonization in patients wearing dental prosthesis.

    PubMed

    Baena-Monroy, Tania; Moreno-Maldonado, Víctor; Franco-Martínez, Fernando; Aldape-Barrios, Beatriz; Quindós, Guillermo; Sánchez-Vargas, Luis Octavio

    2005-04-01

    Denture stomatitis is associated to Candida albicans, different bacteria and other co-factors such as an acid pH, a carbohydrate ingestion increase, different systemic illnesses and pharmacological treatments. The aim of this study was to determine Candida albicans, Staphylococcus aureus and Streptococcus mutans prevalence in the mucous membrane and prosthesis of patients with and without atrophic denture stomatitis and its relationship with other potential clinical co-factors. Saliva was collected from 105 patients (62 female and 43 male) wearing dental prosthesis in order to measure their pH. Oral samples of the mucous membrane and the internal surface of dental prosthesis were taken with sterile cotton to proceed with the microbiological study. The identification of the isolated microorganisms was performed using conventional microbiological methods. Diabetes and Hypertension were the most frequent systemic illnesses. High carbohydrate ingestion was observed in numerous patients. Atrophic denture stomatitis was reported in 50 patients and the pH average in saliva was of 5.2. The presence of C albicans, S. aureus and S. mutans in the mucous membrane and prosthesis was of 51.4%, 52.4% and 67.6%, respectively. C. albicans was isolated in 66.7% from the prosthesis, whereas S. aureus and S. mutans were isolated in 49.5% of those same prosthesis. C. albicans was isolated in 86% of the patients with atrophic denture stomatitis and S. aureus was isolated in a similar percentage (84% of patients). The isolation of S. mutans was less frequent, and it was observed in 16% of the oral samples of these patients. C. albicans, S. aureus and S. mutans frequently colonize the oral mucous of patients wearing dental prosthesis. This illness-bearing condition is more frequent in patients with denture stomatitis, even though dental prosthesis colonization is lower than in the oral mucous.

  7. Lactobacillus is able to alter the virulence and the sensitivity profile of Candida albicans.

    PubMed

    Oliveira, V M C; Santos, S S F; Silva, C R G; Jorge, A O C; Leão, M V P

    2016-12-01

    The study investigated whether the interaction with Lactobacillus rhamnosus (ATCC7469) interfere with the expression of virulence factors by Candida albicans (ATCC18804). These micro-organisms were grown in biofilms for 24, 48 and 72 h, Candida was isolated and the expression of the major virulence factors were investigated. The production of phospholipase, protease and haemolysin were observed in appropriate media; observation of germ tubes formation in serum; biofilm formation, after growth in microtitre plates and reading in spectrophotometer. Candida was also tested for antifungal sensitivity to amphotericin B, fluconazole and ketoconazole. The results were compared with the cells of Candida grown in the absence of lactobacilli (control group). Candida cells, which interacted with Lact. rhamnosus (test group), showed significantly lower proteinase and haemolysin activity, when compared with control group. The germ tube formation and biofilm formation capacity also decreased in tested groups, which demonstrated alterations in susceptibility to antifungal drugs. The results suggest that Lact. rhamnosus is able to influence the expression of virulence factors by C. albicans and can alter its antifungal sensitivity profile. These results suggest reduction in the pathogenicity of Candida and improvement in candidiasis therapy and control. © 2016 The Society for Applied Microbiology.

  8. A Candida albicans CRISPR system permits genetic engineering of essential genes and gene families.

    PubMed

    Vyas, Valmik K; Barrasa, M Inmaculada; Fink, Gerald R

    Candida albicans is a pathogenic yeast that causes mucosal and systematic infections with high mortality. The absence of facile molecular genetics has been a major impediment to analysis of pathogenesis. The lack of meiosis coupled with the absence of plasmids makes genetic engineering cumbersome, especially for essential functions and gene families. We describe a C. albicans CRISPR system that overcomes many of the obstacles to genetic engineering in this organism. The high frequency with which CRISPR-induced mutations can be directed to target genes enables easy isolation of homozygous gene knockouts, even without selection. Moreover, the system permits the creation of strains with mutations in multiple genes, gene families, and genes that encode essential functions. This CRISPR system is also effective in a fresh clinical isolate of undetermined ploidy. Our method transforms the ability to manipulate the genome of Candida and provides a new window into the biology of this pathogen.

  9. 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. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. 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.

  11. Secretory component mediates Candida albicans binding to epithelial cells.

    PubMed

    van der Wielen, P A; Holmes, A R; Cannon, R D

    2016-01-01

    Candida albicans attaches to oral surfaces via a number of mechanisms including adherence mediated by salivary components adsorbed to the C. albicans cell surface. Our goal was to identify the salivary molecules involved. Biotinylated salivary polypeptides that were bound by C. albicans were detected in extracts from washed, saliva-treated yeast cells by polyacrylamide gel electrophoresis and electroblot or immunoblot transfer analysis and purified by electroelution. Purified material was tested for the ability to promote the adherence of radiolabelled C. albicans yeast cells to cultured epithelial monolayers. Three of the polypeptides bound by C. albicans cells were identified as components of secretory IgA, including secretory component. Using non-denaturing polyacrylamide gel electrophoresis, we demonstrated that secretory component could be detected in its free form in saliva, and was bound by yeast cells. Secretory component which was purified by electroelution from non-denaturing PAGE-separated saliva, without detectable complete IgA, promoted adherence of yeast cells to cultured epithelial monolayers in a dose-dependent fashion. These results indicate that despite the inhibitory effect on adherence of IgA specific to C. albicans, IgA components, in particular secretory component, also promote binding to cultured epithelial monolayers. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  12. Antifungal activity of Morinda citrifolia fruit extract against Candida albicans.

    PubMed

    Jainkittivong, Aree; Butsarakamruha, Tassanee; Langlais, Robert P

    2009-09-01

    The objective of the study was to investigate the antifungal activity of Morinda citrifolia fruit extract on Candida albicans. Juice extract from M. citrifolia fruit was lyophilized and used in antifungal testing. Antifungal activity of M. citrifolia fruit extract against C. albicans was tested in vitro at various concentrations and for different contact times. The inhibitory effect of M. citrifolia extract on C. albicans was determined by cultures and an applied broth dilution test. Using cultures, growth of C. albicans was not detected with 50 mg/mL of extract at 30-minute contact time or with 60 mg/mL of extract at 15-minute contact time. By the broth dilution test, the minimum fungicidal concentration of extract against C. albicans was 40 mg/mL at 90-minute contact time or with 50 mg/mL at 15-minute contact time. M. citrifolia fruit extract had an antifungal effect on C. albicans and the inhibitory effect varied with concentration and contact time.

  13. Mechanism underlying renal failure caused by pathogenic Candida albicans infection.

    PubMed

    Jae-Chen, Shin; Young-Joo, Jeon; Seon-Min, Park; Kang Seok, Seo; Jung-Hyun, Shim; Jung-Il, Chae

    2015-03-01

    Candida albicans (C. albicans) is an opportunistic fungal pathogen that commonly causes nosocomial infections. Systemic candidiasis is encountered with increasing frequency in immunocompromised hosts, leading to renal failure that results in severe morbidity and mortality. The present study investigated the mechanisms underlying kidney susceptibility following infection with several C. albicans strains, such as B311 and SC5314. Fungal growth of the highly virulent SC5314 strain was 10(3)-fold higher compared to the nonpathogenic B311 strain in the kidneys. An intravenous challenge of SC5314 in mice, elevated blood urea nitrogen (BUN) and creatine levels, which resulted in mortality at 8 or 35 days after infection in a dose- and time-dependent manner, whereas all the B311-infected mice had BUN and creatinine levels in the normal range and survived. Whether virulent C. albicans may escape clearance by activating signaling pathways that lead to the production of pro-inflammatory cytokines, such as tumor necrosis factor (TNF)-α and interleukin (IL)-1β, was investigated. B311 infections significantly elevated TNF-α and IL-1β mRNA expression in the kidneys, whereas the expression in SC5314-infected mice remained unchanged. Furthermore, B311 infection significantly elevated the plasma levels of TNF-α and IL-1β. These results indicated that the less virulent strains of C. albicans induced pro-inflammatory cytokines in mice. These results determined that an impairment of the protective mechanisms occurred in the kidneys with virulent C. albicans infection.

  14. In vitro damage of Candida albicans biofilms by chitosan

    PubMed Central

    PU, YU; LIU, AIBO; ZHENG, YUQIANG; YE, BIN

    2014-01-01

    With the increasing usage of indwelling medical devices in clinical practice, the frequency of fungal infections has increased, such as that of Candida albicans (C. albicans). Biofilms, a protected niche for microorganisms, are resistant to a range of current antifungal agents. Chitosan is a polyatomic biopolymer with advantageous biocompatibility, biodegradation, nontoxicity and antibacterial properties. To investigate the inhibitory effect of chitosan on biofilms formed by C. albicans, cell viability, 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-caboxanilide reduction, and morphological assays, including fluorescence microscopy and scanning electron microscopy (SEM), were employed. As assessed by cell viability assay, chitosan showed significant inhibitory effects on the planktonic cells and the biofilm of C. albicans in a dose-dependent manner. Fluorescence microscopy and SEM assays confirmed that the chitosan-treated group showed delayed C. albicans biofilm formation with defect morphological features, due to the inhibitory effects of the vast majority of fungal cell growth. In conclusion, C. albicans biofilms were compromised by the treatment with chitosan, providing an alternative therapeutic strategy against the fungal biofilms in the medical devices. PMID:25120626

  15. Anti-biofilm Properties of Peganum harmala against Candida albicans

    PubMed Central

    Aboualigalehdari, Elham; Sadeghifard, Nourkhoda; Taherikalani, Morovat; Zargoush, Zaynab; Tahmasebi, Zahra; Badakhsh, Behzad; Rostamzad, Arman; Ghafourian, Sobhan; Pakzad, Iraj

    2016-01-01

    Objectives Vaginitis still remains as a health issue in women. It is notable that Candida albicans producing biofilm is considered a microorganism responsible for vaginitis with hard to treat. Also, Peganum harmala was applied as an anti fungal in treatment for many infections in Iran. Therefore, this study goal to investigate the role of P. harmala in inhibition of biofilm formation in C. albicans. Methods So, 27 C. albicans collected from women with Vaginitis, then subjected for biofilm formation assay. P. harmala was applied as antibiofilm formation in C. albicans. Results Our results demonstrated that P. harmala in concentration of 12 μg/ml easily inhibited strong biofilm formation; while the concentrations of 10 and 6 μg/ml inhibited biofilm formation in moderate and weak biofilm formation C. albicans strains, respectively. Conclusion Hence, the current study presented P. harmala as antibiofilm herbal medicine for C. albicans; but in vivo study suggested to be performed to confirm its effectiveness. PMID:27169010

  16. 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

  17. Antifungal activity of plant extracts against Candida albicans.

    PubMed

    Perez, C; Suarez, C

    1997-01-01

    In previous papers, we reported the antimicrobial activity of plants used in Argentine folk medicine against different micro-organisms. The present study deals with the screening of 11 of these plants against the opportunistic pathogen fungus Candida albicans. Aqueous extracts 6% p/v (6 mg dry plant per 100 ml of water) were checked against fungus cultures by the agar-well diffusion method. Five extracts showed antifungal activity.

  18. A morphogenetic regulatory role for ethyl alcohol in Candida albicans.

    PubMed

    Chauhan, Nitin M; Raut, Jayant S; Karuppayil, S Mohan

    2011-11-01

    Regulation of morphogenesis through the production of chemical signalling molecules such as isoamyl alcohol, 2-phenylethyl alcohol, 1-dodecanol, E-nerolidol and farnesol is reported in Candida albicans. The present study focuses on the effect of ethyl alcohol on C. albicans dimorphism and biofilm development. Ethyl alcohol inhibited germ tube formation induced by the four standard inducers in a concentration-dependent manner. The germ tube inhibitory concentration (4%) did not have any effect on the growth and viability of C. albicans cells. Ethyl alcohol also inhibited the elongation of germ tubes. Four percentage of ethyl alcohol significantly inhibited biofilm development on polystyrene and silicone surfaces. We suggest a potential morphogenetic regulatory role for ethyl alcohol, which may influence dissemination, virulence and establishment of infection. © 2011 Blackwell Verlag GmbH.

  19. Genome-wide functional analysis in Candida albicans.

    PubMed

    Motaung, Thabiso E; Ells, Ruan; Pohl, Carolina H; Albertyn, Jacobus; Tsilo, Toi J

    2017-02-08

    Candida albicans is an important etiological agent of superficial and life-threatening infections in individuals with compromised immune systems. To date, we know of several overlapping genetic networks that govern virulence attributes in this fungal pathogen. Classical use of deletion mutants has led to the discovery of numerous virulence factors over the years, and genome-wide functional analysis has propelled gene discovery at an even faster pace. Indeed, a number of recent studies using large-scale genetic screens followed by genome-wide functional analysis has allowed for the unbiased discovery of many new genes involved in C. albicans biology. Here we share our perspectives on the role of these studies in analyzing fundamental aspects of C. albicans virulence properties.

  20. Candida albicans and Enterococcus faecalis in the gut

    PubMed Central

    Garsin, Danielle A; Lorenz, Michael C

    2013-01-01

    The fungus Candida albicans and the gram-positive bacterium Enterococcus faecalis are both normal residents of the human gut microbiome and cause opportunistic disseminated infections in immunocompromised individuals. Using a nematode infection model, we recently showed that co-infection resulted in less pathology and less mortality than infection with either species alone and this was partly explained by an interkingdom signaling event in which a bacterial-derived product inhibits hyphal morphogenesis of C. albicans. In this addendum we discuss these findings in the contest of other described bacterial-fungal interactions and recent data suggesting a potentially synergistic relationship between these two species in the mouse gut as well. We suggest that E. faecalis and C. albicans promote a mutually beneficial association with the host, in effect choosing a commensal lifestyle over a pathogenic one. PMID:23941906

  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. 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

  3. Efficacy of ravuconazole in a murine model of vaginitis by Candida albicans.

    PubMed

    Elizondo-Zertuche, Mariana; Robledo-Leal, Efrén; González, J Gerardo; Ceceñas, Luis A; González, Gloria M

    2015-01-01

    The incidence of vulvovaginal candidiasis, a common infection among healthy women primarily caused by the yeast Candida albicans, has increased significantly in recent years. The purpose of this study was to compare the efficacy of ravuconazole (RVC) and fluconazole (FLC) in the treatment of experimental C. albicans vaginitis. Forty isolates of C. albicans were screened for their in vitro susceptibility to RVC and FLC. A strain of C. albicans that was resistant to FLC (minimum inhibitory concentration [MIC] of >64 μg/ml) was selected for the in vivo study. Treatment regimens for the murine vaginal infection model were (1) 1, 5, 10, and 20 mg/kg RVC once daily, (2) 20 mg/kg RVC twice daily, (3) 20 mg/kg FLC once daily, and (4) 20 mg/kg FLC twice daily. The geometric means of the MIC values at 48 h for all isolates tested were 0.05 and 0.5 μg/ml for RVC and FLC, respectively. Regimens of either RVC or FLC at 20 mg/kg twice daily were more effective to reduce the load of FLC-resistant C. albicans than single dose administration. Complete eradication of C. albicans from the vagina was not observed with RVC or FLC treatment in the animal model, although RVC treatment showed a lower fungal concentration 14 days after drug administration. Copyright © 2013 Revista Iberoamericana de Micología. Published by Elsevier Espana. All rights reserved.

  4. The role of Candida albicans in the severity of multiple sclerosis.

    PubMed

    Saroukolaei, Shahla Amri; Ghabaee, Mojdeh; Shokri, Hojjatollah; Badiei, Alireza; Ghourchian, Shadi

    2016-11-01

    The purpose of this study was to compare the specific activity of proteinase A in Candida albicans (C. albicans) between multiple sclerosis (MS) patients and controls. A total of 135 and 100 C. albicans strains were isolated from superficial surfaces of MS patients and healthy controls. Analytical models (regression and neural network) were applied to predict the severity of MS considering specific enzyme activity (SEA) and other factors which affect the expanded disability status scale (EDSS). The SEA of C. albicans in MS patients (3466.95 ± 277.25 μmol min(-1) mg(-1) ) was significantly more than that of healthy controls (1108.98 ± 294.51 μmol min(-1) mg(-1) ) that was confirmed by regression model (P < 0.001). The SEA had a positive correlation with the severity of MS (P < 0.001, r = 0.65). Analytical models showed that SEA played the most important role (among all included factors that affect on EDSS) in the severity of MS. The SEA of C. albicans in MS patients was significantly more than the healthy controls. The results suggest that the level of SEA of proteinase A and probably the capacity of C. albicans isolates to invade the host tissue is associated with the severity of MS. © 2016 Blackwell Verlag GmbH.

  5. 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

  6. The effect of thyme and tea tree oils on morphology and metabolism of Candida albicans.

    PubMed

    Rajkowska, Katarzyna; Kunicka-Styczyńska, Alina; Maroszyńska, Marta; Dąbrowska, Mariola

    2014-01-01

    Members of Candida species cause significant problems in medicine and in many industrial branches also. In order to prevent from Candida sp. development, essential oils are more and more frequently applied as natural, non-toxic, non-pollutive and biodegradable agents with a broad spectrum of antimicrobial activity. The aim of the research was to determine changes in morphology and metabolic properties of Candida albicans in the presence of thyme and tea tree oils. Changes of enzymatic activity of isolates were observed in the presence of both tested essential oils, and they were primarily associated with loss or decrease of activity of all enzymes detected for control. Furthermore, only for 3 out of 11 isolates additional activity of N-acetyl-β-glucosaminidase, α-mannosidase, α-fucosidase and trypsin was detected. Vivid changes in biochemical profiles were found after treatment with tea tree oil and they were related to loss of ability to assimilate D-xylose, D-sorbitol and D-trehalose. The main differences in morphology of isolates compared to the control strain concerned formation of pseudohyphae structures. Both examined essential oils caused changes in cell and colony morphology, as well as in the metabolism of Candida albicans. However, the extent of differences depends on the type and concentration of an essential oil. The most important finding is the broad spectrum of changes in yeast enzymatic profiles induced by thyme and tea tree oils. It can be supposed that these changes, together with loss of ability to assimilate saccharides could significantly impact Candida albicans pathogenicity.

  7. Candida albicans Is Resistant to Polyglutamine Aggregation and Toxicity

    PubMed Central

    Leach, Michelle D.; Kim, TaeHyung; DiGregorio, Sonja E.; Collins, Cathy; Zhang, Zhaolei; Duennwald, Martin L.; Cowen, Leah E.

    2016-01-01

    Disruption of protein quality control can be detrimental, having toxic effects on single cell organisms and contributing to neurodegenerative diseases such as Alzheimer’s, Parkinson’s and Huntington’s in humans. Here, we examined the effects of polyglutamine (polyQ) aggregation in a major fungal pathogen of humans, Candida albicans, with the goal of identifying new approaches to disable this fungus. However, we discovered that expression of polyQ stretches up to 230Q had no effect on C. albicans ability to grow and withstand proteotoxic stress. Bioinformatics analysis demonstrates that C. albicans has a similarly glutamine-rich proteome to the unicellular fungus Saccharomyces cerevisiae, which exhibits polyQ toxicity with as few as 72Q. Surprisingly, global transcriptional profiles indicated no significant change upon induction of up to 230Q. Proteomic analysis highlighted two key interactors of 230Q, Sis1 and Sgt2; however, loss of either protein had no additional effect on C. albicans toxicity. Our data suggest that C. albicans has evolved powerful mechanisms to overcome the toxicity associated with aggregation-prone proteins, providing a unique model for studying polyQ-associated diseases. PMID:27807047

  8. Septin Function in Candida albicans MorphogenesisD⃞

    PubMed Central

    Warenda, Amy J.; Konopka, James B.

    2002-01-01

    The septin proteins function in the formation of septa, mating projections, and spores in Saccharomyces cerevisiae, as well as in cell division and other processes in animal cells. Candida albicans septins were examined in this study for their roles in morphogenesis of this multimorphic, opportunistically pathogenic fungus, which can range from round budding yeast to elongated hyphae. C. albicans green fluorescent protein labeled septin proteins localized to a tight ring at the bud and pseudohyphae necks and as a more diffuse array in emerging germ tubes of hyphae. Deletion analysis demonstrated that the C. albicans homologs of the S. cerevisiae CDC3 and CDC12 septins are essential for viability. In contrast, the C. albicans cdc10Δ and cdc11Δ mutants were viable but displayed conditional defects in cytokinesis, localization of cell wall chitin, and bud morphology. The mutant phenotypes were not identical, however, indicating that these septins carry out distinct functions. The viable septin mutants could be stimulated to undergo hyphal morphogenesis but formed hyphae with abnormal curvature, and they differed from wild type in the selection of sites for subsequent rounds of hyphal formation. The cdc11Δ mutants were also defective for invasive growth when embedded in agar. These results further extend the known roles of the septins by demonstrating that they are essential for the proper morphogenesis of C. albicans during both budding and filamentous growth. PMID:12181342

  9. Intrauterine Candida albicans infection elicits severe inflammation in fetal sheep

    PubMed Central

    Payne, Matthew S.; Kemp, Matthew W.; Kallapur, Suhas G.; Kannan, Paranthaman Senthamarai; Saito, Masatoshi; Miura, Yuichiro; Newnham, John P.; Stock, Sarah; Ireland, Demelza J.; Kramer, Boris W.; Jobe, Alan H.

    2014-01-01

    Background Preventing preterm birth and subsequent adverse neonatal sequelae is among the greatest clinical challenges of our time. Recent studies suggest a role for Candida spp. in preterm birth and fetal injury, as a result of their colonization of either the vagina and/or the amniotic cavity. We hypothesised that intraamniotic C. albicans would cause a vigorous, acute fetal inflammatory response. Methods Sheep carrying singleton pregnancies received single intraamniotic (IA) injections of either saline (control) or 107 CFU C. albicans 1 or 2 d prior to surgical delivery and euthanasia at 124 ± 2 d gestation. Results Colonization of the amniotic cavity by C. albicans resulted in a modest inflammatory response at 1 d and florid inflammation at 2 d, characterised by fetal thrombocytopenia, lymphopenia and significant increases of inflammatory cytokines/chemokines in the fetal membranes skin, lung and the amniotic fluid. Conclusion Acute colonization of the amniotic cavity by C. albicans causes severe intrauterine inflammation and fetal injury. C. albicans is a potent fetal pathogen which can contribute to adverse pregnancy outcomes. PMID:24632681

  10. Nicotine Enhances Interspecies Relationship between Streptococcus mutans and Candida albicans.

    PubMed

    Liu, Shiyu; Qiu, Wei; Zhang, Keke; Zhou, Xuedong; Ren, Biao; He, Jinzhi; Xu, Xin; Cheng, Lei; Li, Mingyun

    2017-01-01

    Streptococcus mutans and Candida albicans are common microorganisms in the human oral cavity. The synergistic relationship between these two species has been deeply explored in many studies. In the present study, the effect of alkaloid nicotine on the interspecies between S. mutans and C. albicans is explored. We developed a dual-species biofilm model and studied biofilm biomass, biofilm structure, synthesis of extracellular polysaccharides (EPS), and expression of glucosyltransferases (Gtfs). Biofilm formation and bacterial and fungal cell numbers in dual-species biofilms increased in the presence of nicotine. More C. albicans cells were present in the dual-species biofilms in the nicotine-treated groups as determined by scanning electron microscopy. The synthesis of EPS was increased by 1 mg/ml of nicotine as detected by confocal laser scanning microscopy. The result of qRT-PCR showed gtfs expression was upregulated when 1 mg/ml of nicotine was used. We speculate that nicotine promoted the growth of S. mutans, and more S. mutans cells attracted more C. albicans cells due to the interaction between two species. Since S. mutans and C. albicans are putative pathogens for dental caries, the enhancement of the synergistic relationship by nicotine may contribute to caries development in smokers.

  11. Nicotine Enhances Interspecies Relationship between Streptococcus mutans and Candida albicans

    PubMed Central

    Qiu, Wei; Zhang, Keke; Zhou, Xuedong; Ren, Biao; He, Jinzhi; Xu, Xin

    2017-01-01

    Streptococcus mutans and Candida albicans are common microorganisms in the human oral cavity. The synergistic relationship between these two species has been deeply explored in many studies. In the present study, the effect of alkaloid nicotine on the interspecies between S. mutans and C. albicans is explored. We developed a dual-species biofilm model and studied biofilm biomass, biofilm structure, synthesis of extracellular polysaccharides (EPS), and expression of glucosyltransferases (Gtfs). Biofilm formation and bacterial and fungal cell numbers in dual-species biofilms increased in the presence of nicotine. More C. albicans cells were present in the dual-species biofilms in the nicotine-treated groups as determined by scanning electron microscopy. The synthesis of EPS was increased by 1 mg/ml of nicotine as detected by confocal laser scanning microscopy. The result of qRT-PCR showed gtfs expression was upregulated when 1 mg/ml of nicotine was used. We speculate that nicotine promoted the growth of S. mutans, and more S. mutans cells attracted more C. albicans cells due to the interaction between two species. Since S. mutans and C. albicans are putative pathogens for dental caries, the enhancement of the synergistic relationship by nicotine may contribute to caries development in smokers. PMID:28280743

  12. A Photonic Crystal Protein Hydrogel Sensor for Candida albicans.

    PubMed

    Cai, Zhongyu; Kwak, Daniel H; Punihaole, David; Hong, Zhenmin; Velankar, Sachin S; Liu, Xinyu; Asher, Sanford A

    2015-10-26

    We report two-dimensional (2D) photonic crystal (PC) sensing materials that selectively detect Candida albicans (C. albicans). These sensors utilize Concanavalin A (Con A) protein hydrogels with a 2D PC embedded on the Con A protein hydrogel surface, that multivalently and selectively bind to mannan on the C. albicans cell surface to form crosslinks. The resulting crosslinks shrink the Con A protein hydrogel, reduce the 2D PC particle spacing, and blue-shift the light diffracted from the PC. The diffraction shifts can be visually monitored, measured with a spectrometer, or determined from the Debye diffraction ring diameter. Our unoptimized hydrogel sensor has a detection limit of around 32 CFU/mL for C. albicans. This sensor distinguishes between C. albicans and those microbes devoid of cell-surface mannan such as the gram-negative bacterium E. coli. This sensor provides a proof-of-concept for utilizing recognition between lectins and microbial cell surface carbohydrates to detect microorganisms in aqueous environments.

  13. Oxidative Stress Responses in the Human Fungal Pathogen, Candida albicans

    PubMed Central

    da Silva Dantas, Alessandra; Day, Alison; Ikeh, Mélanie; Kos, Iaroslava; Achan, Beatrice; Quinn, Janet

    2015-01-01

    Candida albicans is a major fungal pathogen of humans, causing approximately 400,000 life-threatening systemic infections world-wide each year in severely immunocompromised patients. An important fungicidal mechanism employed by innate immune cells involves the generation of toxic reactive oxygen species (ROS), such as superoxide and hydrogen peroxide. Consequently, there is much interest in the strategies employed by C. albicans to evade the oxidative killing by macrophages and neutrophils. Our understanding of how C. albicans senses and responds to ROS has significantly increased in recent years. Key findings include the observations that hydrogen peroxide triggers the filamentation of this polymorphic fungus and that a superoxide dismutase enzyme with a novel mode of action is expressed at the cell surface of C. albicans. Furthermore, recent studies have indicated that combinations of the chemical stresses generated by phagocytes can actively prevent C. albicans oxidative stress responses through a mechanism termed the stress pathway interference. In this review, we present an up-date of our current understanding of the role and regulation of oxidative stress responses in this important human fungal pathogen. PMID:25723552

  14. 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.

  15. Amino Acid Substitutions in the Cytochrome P-450 Lanosterol 14α-Demethylase (CYP51A1) from Azole-Resistant Candida albicans Clinical Isolates Contribute to Resistance to Azole Antifungal Agents

    PubMed Central

    Sanglard, Dominique; Ischer, Françoise; Koymans, Luc; Bille, Jacques

    1998-01-01

    The cytochrome P-450 lanosterol 14α-demethylase (CYP51A1) of yeasts is involved in an important step in the biosynthesis of ergosterol. Since CYP51A1 is the target of azole antifungal agents, this enzyme is potentially prone to alterations leading to resistance to these agents. Among them, a decrease in the affinity of CYP51A1 for these agents is possible. We showed in a group of Candida albicans isolates from AIDS patients that multidrug efflux transporters were playing an important role in the resistance of C. albicans to azole antifungal agents, but without excluding the involvement of other factors (D. Sanglard, K. Kuchler, F. Ischer, J.-L. Pagani, M. Monod, and J. Bille, Antimicrob. Agents Chemother. 39:2378–2386, 1995). We therefore analyzed in closer detail changes in the affinity of CYP51A1 for azole antifungal agents. A strategy consisting of functional expression in Saccharomyces cerevisiae of the C. albicans CYP51A1 genes of sequential clinical isolates from patients was designed. This selection, which was coupled with a test of susceptibility to the azole derivatives fluconazole, ketoconazole, and itraconazole, enabled the detection of mutations in different cloned CYP51A1 genes, whose products are potentially affected in their affinity for azole derivatives. This selection enabled the detection of five different mutations in the cloned CYP51A1 genes which correlated with the occurrence of azole resistance in clinical C. albicans isolates. These mutations were as follows: replacement of the glycine at position 129 with alanine (G129A), Y132H, S405F, G464S, and R467K. While the S405F mutation was found as a single amino acid substitution in a CYP51A1 gene from an azole-resistant yeast, other mutations were found simultaneously in individual CYP51A1 genes, i.e., R467K with G464S, S405F with Y132H, G129A with G464S, and R467K with G464S and Y132H. Site-directed mutagenesis of a wild-type CYP51A1 gene was performed to estimate the effect of each of these

  16. Enterococcus faecalis Inhibits Hyphal Morphogenesis and Virulence of Candida albicans

    PubMed Central

    Cruz, Melissa R.; Graham, Carrie E.; Gagliano, Bryce C.

    2013-01-01

    The Gram-positive bacterium Enterococcus faecalis and the fungus Candida albicans are both found as commensals in many of the same niches of the human body, such as the oral cavity and gastrointestinal (GI) tract. However, both are opportunistic pathogens and have frequently been found to be coconstituents of polymicrobial infections. Despite these features in common, there has been little investigation into whether these microbes affect one another in a biologically significant manner. Using a Caenorhabditis elegans model of polymicrobial infection, we discovered that E. faecalis and C. albicans negatively impact each other's virulence. Much of the negative effect of E. faecalis on C. albicans was due to the inhibition of C. albicans hyphal morphogenesis, a developmental program crucial to C. albicans pathogenicity. We discovered that the inhibition was partially dependent on the Fsr quorum-sensing system, a major regulator of virulence in E. faecalis. Specifically, two proteases regulated by Fsr, GelE and SerE, were partially required. Further characterization of the inhibitory signal revealed that it is secreted into the supernatant, is heat resistant, and is between 3 and 10 kDa. The substance was also shown to inhibit C. albicans filamentation in the context of an in vitro biofilm. Finally, a screen of an E. faecalis transposon mutant library identified other genes required for suppression of C. albicans hyphal formation. Overall, we demonstrate a biologically relevant interaction between two clinically important microbes that could affect treatment strategies as well as impact our understanding of interkingdom signaling and sensing in the human-associated microbiome. PMID:23115035

  17. Spaceflight enhances cell aggregation and random budding in Candida albicans.

    PubMed

    Crabbé, Aurélie; Nielsen-Preiss, Sheila M; Woolley, Christine M; Barrila, Jennifer; Buchanan, Kent; McCracken, James; Inglis, Diane O; Searles, Stephen C; Nelman-Gonzalez, Mayra A; Ott, C Mark; Wilson, James W; Pierson, Duane L; Stefanyshyn-Piper, Heidemarie M; Hyman, Linda E; Nickerson, Cheryl A

    2013-01-01

    This study presents the first global transcriptional profiling and phenotypic characterization of the major human opportunistic fungal pathogen, Candida albicans, grown in spaceflight conditions. Microarray analysis revealed that C. albicans subjected to short-term spaceflight culture differentially regulated 452 genes compared to synchronous ground controls, which represented 8.3% of the analyzed ORFs. Spaceflight-cultured C. albicans-induced genes involved in cell aggregation (similar to flocculation), which was validated by microscopic and flow cytometry analysis. We also observed enhanced random budding of spaceflight-cultured cells as opposed to bipolar budding patterns for ground samples, in accordance with the gene expression data. Furthermore, genes involved in antifungal agent and stress resistance were differentially regulated in spaceflight, including induction of ABC transporters and members of the major facilitator family, downregulation of ergosterol-encoding genes, and upregulation of genes involved in oxidative stress resistance. Finally, downregulation of genes involved in actin cytoskeleton was observed. Interestingly, the transcriptional regulator Cap1 and over 30% of the Cap1 regulon was differentially expressed in spaceflight-cultured C. albicans. A potential role for Cap1 in the spaceflight response of C. albicans is suggested, as this regulator is involved in random budding, cell aggregation, and oxidative stress resistance; all related to observed spaceflight-associated changes of C. albicans. While culture of C. albicans in microgravity potentiates a global change in gene expression that could induce a virulence-related phenotype, no increased virulence in a murine intraperitoneal (i.p.) infection model was observed under the conditions of this study. Collectively, our data represent an important basis for the assessment of the risk that commensal flora could play during human spaceflight missions. Furthermore, since the low fluid

  18. Cellular Components Mediating Coadherence of Candida albicans and Fusobacterium nucleatum

    PubMed Central

    Wu, T.; Cen, L.; Kaplan, C.; Zhou, X.; Lux, R.; Shi, W.; He, X.

    2015-01-01

    Candida albicans is an opportunistic fungal pathogen found as part of the normal oral flora. It can be coisolated with Fusobacterium nucleatum, an opportunistic bacterial pathogen, from oral disease sites, such as those involved in refractory periodontitis and pulp necrosis. The physical coadherence between these 2 clinically important microbes has been well documented and suggested to play a role in facilitating their oral colonization and colocalization and contributing to polymicrobial pathogenesis. Previous studies indicated that the physical interaction between C. albicans and F. nucleatum was mediated by the carbohydrate components on the surface of C. albicans and the protein components on the Fusobaterium cell surface. However, the identities of the components involved still remain elusive. This study was aimed at identifying the genetic determinants involved in coaggregation between the 2 species. By screening a C. albicans SN152 mutant library and a panel of F. nucleatum 23726 outer membrane protein mutants, we identified FLO9, which encodes a putative adhesin-like cell wall mannoprotein of C. albicans and radD, an arginine-inhibitable adhesin-encoding gene in F. nucleatum that is involved in interspecies coadherence. Consistent with these findings, we demonstrated that the strong coaggregation between wild-type F. nucleatum 23726 and C. albicans SN152 in an in vitro assay could be greatly inhibited by arginine and mannose. Our study also suggested a complex multifaceted mechanism underlying physical interaction between C. albicans and F. nucleatum and for the first time revealed the identity of major genetic components involved in mediating the coaggregation. These observations provide useful knowledge for developing new targeted treatments for disrupting interactions between these 2 clinically relevant pathogens. PMID:26152186

  19. Population Structure of Candida albicans from Three Teaching Hospitals in Ghana.

    PubMed

    Adjapong, Gloria; Hale, Marie; Garrill, Ashley

    2016-02-01

    Previous studies on Candida species in a clinical setting in Ghana have shown a prevalence of Candida albicans. Despite this, very little is known about the various strain types and their population genetic structure. In this study three microsatellite loci, CAI, CAIII and CAVI, were used to investigate the population genetic structure of C. albicans from clinical isolates in Ghana. In all, 240 clinically unrelated C. albicans isolates were recovered from patients reporting at three teaching hospitals. All the isolates were heterozygous for at least one of the three loci, except for one isolate, which was homozygous for all three loci. Sixty-seven unique alleles and 240 different genotypes were generated by the three polymorphic microsatellite loci, resulting in a very high discriminatory potential of approximately 0.98. There was no significant difference in allele frequencies from the small number of anatomical sites sampled, regardless of the host conditions although high genotypic diversities were observed among the isolates. There was evidence for clonal reproduction, including over-expression of observed heterozygotes across the populations. The populations deviated significantly from Hardy-Weinberg equilibrium and pair-wise genotypic linkage disequilibria comparisons across the three loci were significant, also suggesting a clonal population. The overall Wright FIS for the three loci was negative, and the overall FST value was not significantly different from zero for the three loci analyzed, indicating a clonal and homogeneous population across the three sampling locations from Ghana.

  20. Candida albicans Impairments Induced by Peppermint and Clove Oils at Sub-Inhibitory Concentrations

    PubMed Central

    Rajkowska, Katarzyna; Otlewska, Anna; Kunicka-Styczyńska, Alina; Krajewska, Agnieszka

    2017-01-01

    Members of Candida species cause significant health problems, inducing various types of superficial and deep-seated mycoses in humans. In order to prevent from Candida sp. development, essential oils are more and more frequently applied, due to their antifungal activity, low toxicity if used appropriately, and biodegrability. The aim of the study was to characterize the early alterations in Candida albicans metabolic properties in relation to proteins and chromosomal DNA profiles, after treatment with peppermint and clove oils at sub-inhibitory concentrations. The yeasts were affected by the oils even at a concentration of 0.0075% v/v, which resulted in changes in colony morphotypes and metabolic activities. Peppermint and clove oils at concentrations ranging from 0.015× MIC (minimal inhibitory concentration) to 0.5× MIC values substantially affected the enzymatic abilities of C. albicans, and these changes were primarily associated with the loss or decrease of activity of all 9 enzymes detected in the untreated yeast. Moreover, 29% isolates showed additional activity of N-acetyl-β-glucosaminidase and 14% isolates—α-fucosidase in comparison to the yeast grown without essential oils addition. In response to essential oils at 0.25–0.5× MIC, extensive changes in C. albicans whole-cell protein profiles were noted. However, the yeast biochemical profiles were intact with the sole exception of the isolate treated with clove oil at 0.5× MIC. The alterations were not attributed to gross chromosomal rearrangements in C. albicans karyotype. The predominantly observed decrease in protein fractions and the yeast enzymatic activity after treatment with the oils should be considered as a phenotypic response of C. albicans to the essential oils at their sub-inhibitory concentrations and may lead to the reduction of this yeast pathogenicity. PMID:28629195

  1. Antifungal activity of essential oils extract from Origanum floribundum Munby, Rosmarinus officinalis L. and Thymus ciliatus Desf. against Candida albicans isolated from bovine clinical mastitis.

    PubMed

    Ksouri, S; Djebir, S; Bentorki, A A; Gouri, A; Hadef, Y; Benakhla, A

    2017-06-01

    The aim of this study is to limit the antibiotic use in mastitis treatment and to find other alternatives. The antifungal activity of the essential oils from Origanum floribundum Munby., Rosmarinus officinalis L. and Thymus ciliatus Desf. is studied in the present work against a Candida albicans reference strain and ten C. albicans isolated strains from bovine clinical mastitis. Essential oils were extracted by hydrodistillation technique using Clevenger apparatus. Their chromatographic analysis was performed with a Gas Chromatograph/Mass Spectrometer (GC/MS). Antifungal activities of essential oils were investigated by macrobroth method of dilution in tubes to determine the Minimum Inhibitory Concentrations (MIC 80%). Analysis of the essential oil showed chemical profile dominated by thymol (50.47 and 62.41%) and P-cymene (24.22 and 15.51%) in the oregano and the thyme respectively, 1, 8-cineol (31.50%) and α-pinene (18.33%) in Rosemary. The three essential oils revealed highly effective anticandidal activity, with an MIC of 80% values ranged from 15.02 to 31.08μg/mL. These results suggest that essential oils studied can be real alternatives in the control of mastitis fungi but deserving studies more in-depth and detailed on their application in vivo. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  2. Caspofungin dose escalation for invasive candidiasis due to resistant Candida albicans.

    PubMed

    Wiederhold, Nathan P; Najvar, Laura K; Bocanegra, Rosie A; Kirkpatrick, William R; Patterson, Thomas F

    2011-07-01

    Previous in vivo studies have reported caspofungin dose escalation to be effective against Candida glabrata with reduced susceptibility. We hypothesized that higher doses of caspofungin would be effective against invasive candidiasis caused by the more virulent species Candida albicans, including isolates resistant to this echinocandin. Immunocompetent mice were inoculated with one of three C. albicans isolates, including one susceptible and two resistant isolates with different FKS1 hot spot 1 point mutations. Mice received daily caspofungin treatment for 7 days and were then followed off therapy for 2 weeks to assess survival. Kidney tissue and blood were collected, and fungal burden and serum (1 → 3)-β-D-glucan were measured. Significant differences in virulence were observed among the three C. albicans isolates, which translated into differences in responses to caspofungin. The most virulent of the resistant isolates studied (isolate 43001; Fks1p F641S) did not respond to caspofungin doses of up to 10 mg/kg of body weight, as there were no differences in survival (survival range, 0 to 12% with treatment), tissue burden, or (1 → 3)-β-D-glucan concentration compared to those for untreated controls. Higher doses of caspofungin did improve survival against the second resistant isolate (53264; Fks1p S645P) that demonstrated reduced virulence (5 and 10 mg/kg; 80% survival). In contrast, caspofungin doses as low as 1 mg/kg improved survival (85 to 95%) and reduced tissue burden and (1 → 3)-β-D-glucan concentration against the susceptible isolate (ATCC 90028). These data suggest that caspofungin dose escalation for invasive candidiasis may not be consistently effective against resistant C. albicans isolates, and this may be associated with the virulence of the strain.

  3. Decontamination efficacy of erbium:yttrium-aluminium-garnet and diode laser light on oral Candida albicans isolates of a 5-day in vitro biofilm model.

    PubMed

    Sennhenn-Kirchner, Sabine; Schwarz, Peter; Schliephake, Henning; Konietschke, Frank; Brunner, Edgar; Borg-von Zepelin, Margarete

    2009-05-01

    The different forms of superficial and systemic candidiasis are often associated with biofilm formation on surfaces of host tissues or medical devices. The biofilm formation of Candida spp., in general, necessitates significantly increased amounts of antifungal agents for therapy. Often the therapeutic effect is doubtful. A 5-day biofilm model with oral Candida isolates was established according to Chandra et al. (J Dent Res 80:903-908, 2001) on glass and titanium surfaces and was modified by Sennhenn-Kirchner et al. (Z Zahnärztl Implantol 3:45-51, 2007) to investigate different aspects unanswered in the field of dentistry. In this model, the efficacy of erbium:yttrium-aluminium-garnet (Er:YAG) light (2940 nm, 100 mJ, 10 Hz, 300 micros pulsed mode applied for 80 s) and diode laser light (810 nm, 1 W, continuous wave mode applied for 20 s with four repetitions after 30 s pauses each) was evaluated and compared to untreated controls. The photometric evaluation of the samples was completed by observations on morphological changes of yeast cells grown in the biofilm. Compared to the untreated controls Candida cells grown in mature in vitro biofilms were significantly reduced by both wavelengths investigated. Comparison between the different methods of laser treatment additionally revealed a significantly greater effect of the Er:YAG over the diode laser. Scanning electron microscopy findings proved that the diode laser light was effective in direct contact mode. In contrast, in the areas without direct contact, the fungal cells were left almost unchanged. The Er:YAG laser damaged the fungal cells to a great extent wherever it was applied.

  4. Direct bioethanol production by amylolytic yeast Candida albicans.

    PubMed

    Aruna, A; Nagavalli, M; Girijashankar, V; Ponamgi, S P D; Swathisree, V; Rao, L Venkateswar

    2015-03-01

    An attempt was made to produce bioethanol using optimized fermentation parameters and mutationally improved strain of Candida albicans. The mutant strain OMC3E6 obtained by UV irradiation followed by ethidium bromide successive mutations showed 2.6 times more glucoamylase secretion and 1.5 times more bioethanol production via direct conversion of starch. Enhanced hydrolysis of insoluble starch (72%) and potato starch (70%) was achieved with glucoamylase enzyme preparation from mutant C. albicans. In fermentation medium, the use of maltose, corn steep liquor, NaH2 PO4 , NaCl + MgSO4 and Triton X-100 has increased the glucoamylase production by the microbe. Under optimized conditions, C. albicans eventually produced 437 g ethanol kg(-1) potatoes. Earlier reports mentioned the use of thrice the quantity of starch as reported by us followed by more fermentation period (3-4 days) and demanded pretreatment of starch sources with alpha-amylase as well. Here, we simplified these three steps and obtained 73% conversion of insoluble starch into ethanol via direct conversion method in a period of 2 days without the involvement of cell immobilizations or enzyme pretreatment steps. Due to fast depletion of fossil fuels in the modern world, bioethanol usage as an alternate energy source is the need of the hour. For the first time, we report bioethanol production by Candida albicans via direct conversion of starchy biomass into ethanol along with enhanced starch-hydrolysing capacity and ethanol conversion ratio. So far, C. albicans was dealt in the field of clinical pathology, but here we successfully employed this organism to produce bioethanol from starchy agri-substrates. Optimizing fermentation parameters and improving the microbial strains through successive mutagenesis can improve the end product yield. © 2014 The Society for Applied Microbiology.

  5. Polymicrobial biofilm formation by Candida albicans, Actinomyces naeslundii, and Streptococcus mutans is Candida albicans strain and medium dependent.

    PubMed

    Arzmi, Mohd Hafiz; Alnuaimi, Ali D; Dashper, Stuart; Cirillo, Nicola; Reynolds, Eric C; McCullough, Michael

    2016-11-01

    Oral biofilms comprise of extracellular polysaccharides and polymicrobial microorganisms. The objective of this study was to determine the effect of polymicrobial interactions of Candida albicans, Actinomyces naeslundii, and Streptococcus mutans on biofilm formation with the hypotheses that biofilm biomass and metabolic activity are both C. albicans strain and growth medium dependent. To study monospecific biofilms, C. albicans, A. naeslundii, and S. mutans were inoculated into artificial saliva medium (ASM) and RPMI-1640 in separate vials, whereas to study polymicrobial biofilm formation, the inoculum containing microorganisms was prepared in the same vial prior inoculation into a 96-well plate followed by 72 hours incubation. Finally, biofilm biomass and metabolic activity were measured using crystal violet and XTT assays, respectively. Our results showed variability of monospecies and polymicrobial biofilm biomass between C. albicans strains and growth medium. Based on cut-offs, out of 32, seven RPMI-grown biofilms had high biofilm biomass (HBB), whereas, in ASM-grown biofilms, 14 out of 32 were HBB. Of the 32 biofilms grown in RPMI-1640, 21 were high metabolic activity (HMA), whereas in ASM, there was no biofilm had HMA. Significant differences were observed between ASM and RPMI-grown biofilms with respect to metabolic activity (P <01). In conclusion, biofilm biomass and metabolic activity were both C. albicans strain and growth medium dependent. © The Author 2016. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  6. 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.

  7. 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

  8. Denture disinfection by microwave energy: influence of Candida albicans biofilm.

    PubMed

    Senna, Plínio Mendes; da Silva, Wander José; Cury, Altair Antoninha Del Bel

    2012-06-01

    This study evaluated the influence of the area of Candida albicans biofilm on denture disinfection by microwave energy. Candida albicans biofilm was allowed to form for 72 h on resin discs, and three small coverage or seven large coverage discs were placed onto the palatal surface of sterile maxillary dentures. Each denture was immersed in 200 ml distilled water and individually irradiated at a power of 450, 630 or 900 W for different time intervals (1, 2 or 3 min) (n = 6). The effectiveness of disinfection was evaluated by counting the residual cells. The data were analysed by anova and Tukey's HSD test (α = 0.05). Pearson's correlation test was performed to determine the correlation between effectiveness of sterilisation and temperature. Dentures with a larger area of biofilm demanded a longer irradiation exposure to achieve disinfection (p < 0.001), irrespective of power setting, and in this time no yeast growth was detected. Dentures with small areas of biofilm were disinfected after 1 min at 900 W and 2 min at 450 or 630 W. A positive correlation was found between water temperature and effectiveness of disinfection (r = 0.6170; p < 0.001). The C. albicans biofilm area influenced disinfection by microwave energy; therefore dentures with larger biofilm areas required longer irradiation exposure to be disinfected. © 2010 The Gerodontology Society and John Wiley & Sons A/S.

  9. A Human-Curated Annotation of the Candida albicans Genome

    PubMed Central

    Braun, Burkhard R; van het Hoog, Marco; d'Enfert, Christophe; Martchenko, Mikhail; Dungan, Jan; Kuo, Alan; Inglis, Diane O; Uhl, M. Andrew; Hogues, Hervé; Berriman, Matthew; Lorenz, Michael; Levitin, Anastasia; Oberholzer, Ursula; Bachewich, Catherine; Harcus, Doreen; Marcil, Anne; Dignard, Daniel; Iouk, Tatiana; Zito, Rosa; Frangeul, Lionel; Tekaia, Fredj; Rutherford, Kim; Wang, Edwin; Munro, Carol A; Bates, Steve; Gow, Neil A; Hoyer, Lois L; Köhler, Gerwald; Morschhäuser, Joachim; Newport, George; Znaidi, Sadri; Raymond, Martine; Turcotte, Bernard; Sherlock, Gavin; Costanzo, Maria; Ihmels, Jan; Berman, Judith; Sanglard, Dominique; Agabian, Nina; Mitchell, Aaron P; Johnson, Alexander D; Whiteway, Malcolm; Nantel, André

    2005-01-01

    Recent sequencing and assembly of the genome for the fungal pathogen Candida albicans used simple automated procedures for the identification of putative genes. We have reviewed the entire assembly, both by hand and with additional bioinformatic resources, to accurately map and describe 6,354 genes and to identify 246 genes whose original database entries contained sequencing errors (or possibly mutations) that affect their reading frame. Comparison with other fungal genomes permitted the identification of numerous fungus-specific genes that might be targeted for antifungal therapy. We also observed that, compared to other fungi, the protein-coding sequences in the C. albicans genome are especially rich in short sequence repeats. Finally, our improved annotation permitted a detailed analysis of several multigene families, and comparative genomic studies showed that C. albicans has a far greater catabolic range, encoding respiratory Complex 1, several novel oxidoreductases and ketone body degrading enzymes, malonyl-CoA and enoyl-CoA carriers, several novel amino acid degrading enzymes, a variety of secreted catabolic lipases and proteases, and numerous transporters to assimilate the resulting nutrients. The results of these efforts will ensure that the Candida research community has uniform and comprehensive genomic information for medical research as well as for future diagnostic and therapeutic applications. PMID:16103911

  10. Construction of FLAG tagging vectors for Candida albicans.

    PubMed

    Umeyama, Takashi; Nagai, Yuki; Niimi, Masakazu; Uehara, Yoshimasa

    2002-05-01

    We have constructed three new vectors for Candida albicans (pFLAG-Act1, pFLAG-Mal2, and pFLAG-Met3). The proteins can be expressed as C-terminal FLAG-tagged proteins under the control of different promoters (ACT1, MAL2, and MET3). To confirm the protein expression, we used the Renilla reniformis luciferase and the drug efflux pump Cdr1p of Candida albicans as reporters. The luciferase protein expressed by the MET3 promoter was found to have the strongest activity of the three promoters when cultured in a methionine-depleted synthetic medium. Cdr1p was expressed as a C-terminal FLAG-tagged protein using either these vectors or PCR-mediated integration. The fluconazole resistance was increased by the Cdr1p expression in a CDR1 homozygous disruptant. The expressed proteins were detected by Western blotting using the anti-FLAG antibody. We also constructed a Cdr1p-FLAG expressing strain, in which we directly tagged Cdr1p with FLAG on the genome loci, using a PCR-based integrative marker cassette that was amplified using the pFLAG vector. We then confirmed the protein expression by Western blotting. Thus, these new vectors are useful as C. albicans genetic tools. Copyright 2002 John Wiley & Sons, Ltd.

  11. 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.

  12. 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.

  13. DLH1 is a functional Candida albicans homologue of the meiosis-specific gene DMC1

    SciTech Connect

    Diener, A.C.; Fink, G.R.

    1996-06-01

    DMC1/LIM15 homologue 1 (DLH1), a gene related to meiosis-specific genes, has been isolated from Candida albicans, a fungus thought not to undergo meiosis. The deduced protein sequence of DLH1 contains 74% amino acid identity with Dmc1p from Saccharomyces cerevisiae and 63% with Lim15p from the plant Lilium longiflorum, meiosis-specific homologous of Escherichia coli RecA. Candida DLH1 complements a dmc1/dmc1 null mutant in S. cerevisiae. High copy expression of DLH1 restores both sporulation and meiotic recombination to a Saccharomyces dmc1/{Delta}/dmc1{Delta} strain. Unlike the DMC1 gene, which is transcribed only in meiotic cells, the heterologous Candida DLH1 gene is transcribed in both vegetative and meiotic cells of S. cerevisiae. Transcription of DLH1 is not detected or induced in C. albicans under conditions that induce DMC1 and meiosis in S. cerevisiae. The presence of an intact homologue of a meiosis-specific gene in C. albicans raises the possibility that this organism has a cryptic meiotic pathway. 25 refs., 6 figs., 3 tabs.

  14. Spaceflight Enhances Cell Aggregation and Random Budding in Candida albicans

    PubMed Central

    Woolley, Christine M.; Barrila, Jennifer; Buchanan, Kent; McCracken, James; Inglis, Diane O.; Searles, Stephen C.; Nelman-Gonzalez, Mayra A.; Ott, C. Mark; Wilson, James W.; Pierson, Duane L.; Stefanyshyn-Piper, Heidemarie M.; Hyman, Linda E.; Nickerson, Cheryl A.

    2013-01-01

    This study presents the first global transcriptional profiling and phenotypic characterization of the major human opportunistic fungal pathogen, Candida albicans, grown in spaceflight conditions. Microarray analysis revealed that C. albicans subjected to short-term spaceflight culture differentially regulated 452 genes compared to synchronous ground controls, which represented 8.3% of the analyzed ORFs. Spaceflight-cultured C. albicans–induced genes involved in cell aggregation (similar to flocculation), which was validated by microscopic and flow cytometry analysis. We also observed enhanced random budding of spaceflight-cultured cells as opposed to bipolar budding patterns for ground samples, in accordance with the gene expression data. Furthermore, genes involved in antifungal agent and stress resistance were differentially regulated in spaceflight, including induction of ABC transporters and members of the major facilitator family, downregulation of ergosterol-encoding genes, and upregulation of genes involved in oxidative stress resistance. Finally, downregulation of genes involved in actin cytoskeleton was observed. Interestingly, the transcriptional regulator Cap1 and over 30% of the Cap1 regulon was differentially expressed in spaceflight-cultured C. albicans. A potential role for Cap1 in the spaceflight response of C. albicans is suggested, as this regulator is involved in random budding, cell aggregation, and oxidative stress resistance; all related to observed spaceflight-associated changes of C. albicans. While culture of C. albicans in microgravity potentiates a global change in gene expression that could induce a virulence-related phenotype, no increased virulence in a murine intraperitoneal (i.p.) infection model was observed under the conditions of this study. Collectively, our data represent an important basis for the assessment of the risk that commensal flora could play during human spaceflight missions. Furthermore, since the low fluid

  15. Factors Supporting Cysteine Tolerance and Sulfite Production in Candida albicans

    PubMed Central

    Hennicke, Florian; Grumbt, Maria; Lermann, Ulrich; Ueberschaar, Nico; Palige, Katja; Böttcher, Bettina; Jacobsen, Ilse D.; Staib, Claudia; Morschhäuser, Joachim; Monod, Michel; Hube, Bernhard; Hertweck, Christian

    2013-01-01

    The amino acid cysteine has long been known to be toxic at elevated levels for bacteria, fungi, and humans. However, mechanisms of cysteine tolerance in microbes remain largely obscure. Here we show that the human pathogenic yeast Candida albicans excretes sulfite when confronted with increasing cysteine concentrations. Mutant construction and phenotypic analysis revealed that sulfite formation from cysteine in C. albicans relies on cysteine dioxygenase Cdg1, an enzyme with similar functions in humans. Environmental cysteine induced not only the expression of the CDG1 gene in C. albicans, but also the expression of SSU1, encoding a putative sulfite efflux pump. Accordingly, the deletion of SSU1 resulted in enhanced sensitivity of the fungal cells to both cysteine and sulfite. To study the regulation of sulfite/cysteine tolerance in more detail, we screened a C. albicans library of transcription factor mutants in the presence of sulfite. This approach and subsequent independent mutant analysis identified the zinc cluster transcription factor Zcf2 to govern sulfite/cysteine tolerance, as well as cysteine-inducible SSU1 and CDG1 gene expression. cdg1Δ and ssu1Δ mutants displayed reduced hypha formation in the presence of cysteine, indicating a possible role of the newly proposed mechanisms of cysteine tolerance and sulfite secretion in the pathogenicity of C. albicans. Moreover, cdg1Δ mutants induced delayed mortality in a mouse model of disseminated infection. Since sulfite is toxic and a potent reducing agent, its production by C. albicans suggests diverse roles during host adaptation and pathogenicity. PMID:23417561

  16. 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

  17. Nanoscopic cell-wall architecture of an immunogenic ligand in Candida albicans during antifungal drug treatment

    PubMed Central

    Lin, Jia; Wester, Michael J.; Graus, Matthew S.; Lidke, Keith A.; Neumann, Aaron K.

    2016-01-01

    The cell wall of Candida albicans is composed largely of polysaccharides. Here we focus on β-glucan, an immunogenic cell-wall polysaccharide whose surface exposure is often restricted, or “masked,” from immune recognition by Dectin-1 on dendritic cells (DCs) and other innate immune cells. Previous research suggested that the physical presentation geometry of β-glucan might determine whether it can be recognized by Dectin-1. We used direct stochastic optical reconstruction microscopy to explore the fine structure of β-glucan exposed on C. albicans cell walls before and after treatment with the antimycotic drug caspofungin, which alters glucan exposure. Most surface-accessible glucan on C. albicans yeast and hyphae is limited to isolated Dectin-1–binding sites. Caspofungin-induced unmasking caused approximately fourfold to sevenfold increase in total glucan exposure, accompanied by increased phagocytosis efficiency of DCs for unmasked yeasts. Nanoscopic imaging of caspofungin-unmasked C. albicans cell walls revealed that the increase in glucan exposure is due to increased density of glucan exposures and increased multiglucan exposure sizes. These findings reveal that glucan exhibits significant nanostructure, which is a previously unknown physical component of the host–Candida interaction that might change during antifungal chemotherapy and affect innate immune activation. PMID:26792838

  18. Antifungal activity of caspofungin in experimental infective endocarditis caused by Candida albicans.

    PubMed

    Victorio, Gerardo Becerra; Bourdon, Lorena Michele Brennan; Benavides, Leonel García; Huerta-Olvera, Selene G; Plascencia, Arturo; Villanueva, José; Martinez-Lopez, Erika; Hernández-Cañaveral, Iván Isidro

    2017-05-01

    Infective endocarditis is a disease characterised by heart valve lesions, which exhibit extracellular matrix proteins that act as a physical barrier to prevent the passage of antimicrobial agents. The genus Candida has acquired clinical importance given that it is increasingly being isolated from cases of nosocomial infections. To evaluate the activity of caspofungin compared to that of liposomal amphotericin B against Candida albicans in experimental infective endocarditis. Wistar rats underwent surgical intervention and infection with strains of C. albicans to develop infective endocarditis. Three groups were formed: the first group was treated with caspofungin, the second with liposomal amphotericin B, and the third received a placebo. In vitro sensitivity was first determined to further evaluate the effect of these treatments on a rat experimental model of endocarditis by semiquantitative culture of fibrinous vegetations and histological analysis. Our semiquantitative culture of growing vegetation showed massive C. albicans colonisation in rats without treatment, whereas rats treated with caspofungin showed significantly reduced colonisation, which was similar to the results obtained with liposomal amphotericin B. The antifungal activity of caspofungin is similar to that of liposomal amphotericin B in an experimental model of infective endocarditis caused by C. albicans.

  19. Nuclear fusion occurs during mating in Candida albicans and is dependent on the KAR3 gene.

    PubMed

    Bennett, Richard J; Miller, Mathew G; Chua, Penelope R; Maxon, Mary E; Johnson, Alexander D

    2005-02-01

    It is now well established that mating can occur between diploid a and alpha cells of Candida albicans. There is, however, controversy over when, and with what efficiency, nuclear fusion follows cell fusion to create stable tetraploid a/alpha cells. In this study, we have analysed the mating process between C. albicans strains using both cytological and genetic approaches. Using strains derived from SC5314, we used a number of techniques, including time-lapse microscopy, to demonstrate that efficient nuclear fusion occurs in the zygote before formation of the first daughter cell. Consistent with these observations, zygotes micromanipulated from mating mixes gave rise to mononuclear tetraploid cells, even when no selection for successful mating was applied to them. Mating between different clinical isolates of C. albicans revealed that while all isolates could undergo nuclear fusion, the efficiency of nuclear fusion varied in different crosses. We also show that nuclear fusion in C. albicans requires the Kar3 microtubule motor protein. Deletion of the CaKAR3 gene from both mating partners had little or no effect on zygote formation but reduced the formation of stable tetraploids more than 600-fold, as determined by quantitative mating assays. These findings demonstrate that nuclear fusion is an active process that can occur in C. albicans at high frequency to produce stable, mononucleate mating products.

  20. Assessing the potential of four cathelicidins for the management of mouse candidiasis and Candida albicans biofilms.

    PubMed

    Yu, Haining; Liu, Xuelian; Wang, Chen; Qiao, Xue; Wu, Sijin; Wang, Hui; Feng, Lan; Wang, Yipeng

    2016-02-01

    As the most common fungal pathogen of humans, severe drug resistance has emerged in the clinically isolated Candida albicans, which lead to the urgency to develop novel antifungal agents. Here, four our previously characterized cathelicidins (cathelicidin-BF, Pc-CATH1, Cc-CATH2, Cc-CATH3) were selected and their antifungal activities against C. albicans were evaluated in vitro and in vivo using amphotericin B and LL-37 as control. Results showed that all four cathelicidins could eradicate standard and clinically isolated C. albicans strains with most MIC values ranging from 1 to 16 μg/ml, in less than 0.5 h revealed by time-kill kinetic assay. Four peptides only exhibited slight hemolytic activity with most HC50 > 200 μg/ml, and retained potent anti-C. albicans activity at salt concentrations below and beyond physiological level. In animal experiment, 50 mg/kg administration of the four cathelicidins could significantly reduce the fungal counts in a murine oral candidiasis model induced by clinically isolated C. albicans. The antibiofilm activity of cathelicidin-BF, the most potent among the five peptides was evaluated, and result showed that cathelicidin-BF strongly inhibited C. albicans biofilm formation at 20 μg/ml. Furthermore, cathelicidin-BF also exhibited potent anti-C. albicans activity in established biofilms as measured by metabolic and fluorescent viability assays. Structure-function analyses suggest that they mainly adopt an α-helical conformations, which enable them to act as a membrane-active molecule. Altogether, the four cathelicidins display great potential for antifungal agent development against candidiasis.

  1. 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

  2. Oral Candida albicans biotypes in Chinese patients with and without oral candidosis.

    PubMed

    Xu, Y Y; Samaranayake, L P

    1995-06-01

    A total of 53 oral Candida albicans isolates from Chinese patients with clinically diagnosed oral candidosis (27 patients) or without overt signs and mycological manifestations of infection (26) were biotyped using two commercially available API micromethod kits and a boric acid-resistance test. There were no significant differences in the biotypes in health and disease, although the biotype A1R was present only in diseased individuals. The biotype A1S accounted for 21% of the total isolates, as in a number of other previous studies from the West. However, 14 of the 27 biotypes characterized were new biotypes that have not been described before. These preliminary data indicate that biotypic profile of C. albicans may bear no relation to the virulence of the isolates, and that diverse subtypes of the fungus are globally prevalent.

  3. Transformations of inorganic mercury by Candida albicans and Saccharomyces cerevisiae

    SciTech Connect

    Yannai, S.; Berdicevsky, I.; Duek, L. )

    1991-01-01

    Saccharomyces cerevisiae and Candida albicans were incubated with 0.25, 0.5, or 0.75 {mu}g of Hg (as HgCl{sub 2}) per ml of Nelson's medium in the presence of trace amounts of oxygen at 28{degree}C for 12 days. Two control media were used, one without added Hg and one without yeast inoculum. Yeast cell growth was estimated after 1, 2, 3, and 8 days of incubation. The contents of organomercury in the system and of elemental mercury released from the media and collected in traps were determined at the end of the experiments. The results were as follows: (1) C. albicans was the more mercury-resistant species, but both yeast species failed to grown in the media containing 0.75 {mu}g of Hg per ml.; (2) The amounts of organomercury produced by the two species were proportional to the amount of HgCl{sub 2} added to the medium. In all cases C. albicans produced considerably larger amounts of methylmercury than S. cerevisiae; (3) The amounts of elemental Hg produced were inversely proportional to the HgCl{sub 2} level added in the case of S. cerevisiae but were all similar in the case of C. albicans;and (4) Neither organomercury nor elemental Hg was produced in any of the control media.

  4. Disruption of Sphingolipid Biosynthesis Blocks Phagocytosis of Candida albicans

    PubMed Central

    Schmidt, Florian I.; Freinkman, Elizaveta; Dougan, Stephanie; Dougan, Michael; Esteban, Alexandre; Maruyama, Takeshi; Strijbis, Karin; Ploegh, Hidde L.

    2015-01-01

    The ability of phagocytes to clear pathogens is an essential attribute of the innate immune response. The role of signaling lipid molecules such as phosphoinositides is well established, but the role of membrane sphingolipids in phagocytosis is largely unknown. Using a genetic approach and small molecule inhibitors, we show that phagocytosis of Candida albicans requires an intact sphingolipid biosynthetic pathway. Blockade of serine-palmitoyltransferase (SPT) and ceramide synthase-enzymes involved in sphingolipid biosynthesis- by myriocin and fumonisin B1, respectively, impaired phagocytosis by phagocytes. We used CRISPR/Cas9-mediated genome editing to generate Sptlc2-deficient DC2.4 dendritic cells, which lack serine palmitoyl transferase activity. Sptlc2-/- DC2.4 cells exhibited a stark defect in phagocytosis, were unable to bind fungal particles and failed to form a normal phagocytic cup to engulf C. albicans. Supplementing the growth media with GM1, the major ganglioside present at the cell surface, restored phagocytic activity of Sptlc2-/- DC2.4 cells. While overall membrane trafficking and endocytic pathways remained functional, Sptlc2-/- DC2.4 cells express reduced levels of the pattern recognition receptors Dectin-1 and TLR2 at the cell surface. Consistent with the in vitro data, compromised sphingolipid biosynthesis in mice sensitizes the animal to C. albicans infection. Sphingolipid biosynthesis is therefore critical for phagocytosis and in vivo clearance of C. albicans. PMID:26431038

  5. Deltamethrin Increases Candida albicans infection susceptibility in mice.

    PubMed

    Rehman, H; Mohan, A; Tabassum, H; Ahmad, F; Rahman, S; Parvez, S; Raisuddin, S

    2011-05-01

    Deltamethrin, an alpha-cyano type II synthetic pyrethroid insecticide, is used to control a wide range of insects on a variety of crops and vectors of diseases. Deltamethrin has been previously reported for its immunotoxic effects and therefore its exposure may affect the host resistance to infection and tumour challenge. Effect of exposure of deltamethrin on host resistance to Candida albicans infection was examined in Swiss albino mice. The objective of this study was to investigate the modulatory action of deltamethrin in C. albicans infected mice. The dose of deltamethrin was initially tested and selected from our previous study (18 mg/kg). Percentage of infection in deltamethrin treated animals increased faster when compared to that of the controls. Deltamethrin exposure along with C. albicans infection caused alteration of humoral immune response. The number of colony forming unit in liver and spleen were also found to be significantly increased in the treated group. The results from our present study suggest that deltamethrin exhibits an immunosuppressive effect and has a negative impact on host resistance to C. albicans infection. © 2011 The Authors. Scandinavian Journal of Immunology © 2011 Blackwell Publishing Ltd.

  6. Effects of ambroxol on Candida albicans growth and biofilm formation.

    PubMed

    Rene, Hernandez-Delgadillo; José, Martínez-Sanmiguel Juan; Isela, Sánchez-Nájera Rosa; Claudio, Cabral-Romero

    2014-04-01

    Typically, the onset of candidiasis is characterised by the appearance of a biofilm of Candida albicans, which is associated with several diseases including oral candidiasis in young and elderly people. The objective of this work was to investigate the in vitro fungicidal activity as well as the antibiofilm activity of ambroxol (AMB) against C. albicans growth. In the present investigation, the fungicidal activity of AMB was established using the cell viability 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Also the minimum inhibitory concentration (MIC) of AMB required to inhibit the fungal growth was determined. Simultaneously, the antibiofilm activity of AMB was evaluated using fluorescence microscopy. The study revealed that 2 mg ml(-1) of AMB exhibited higher fungicidal activity than 3.3 mg ml(-1) of terbinafine, one of most common commercial antifungals. A MIC of 1 mg ml(-1) was determined for AMB to interfere with C. albicans growth. Furthermore, AMB was found to be effective in inhibiting the biofilm formation of C. albicans and exerted its fungicidal activity against the fungal cells interspersed in the preformed biofilm. The study suggests a potential role of the mucolytic agent, AMB, as an interesting therapeutic alternative in the treatment of oral candidiasis. © 2013 Blackwell Verlag GmbH.

  7. Disruption of Sphingolipid Biosynthesis Blocks Phagocytosis of Candida albicans.

    PubMed

    Tafesse, Fikadu G; Rashidfarrokhi, Ali; Schmidt, Florian I; Freinkman, Elizaveta; Dougan, Stephanie; Dougan, Michael; Esteban, Alexandre; Maruyama, Takeshi; Strijbis, Karin; Ploegh, Hidde L

    2015-10-01

    The ability of phagocytes to clear pathogens is an essential attribute of the innate immune response. The role of signaling lipid molecules such as phosphoinositides is well established, but the role of membrane sphingolipids in phagocytosis is largely unknown. Using a genetic approach and small molecule inhibitors, we show that phagocytosis of Candida albicans requires an intact sphingolipid biosynthetic pathway. Blockade of serine-palmitoyltransferase (SPT) and ceramide synthase-enzymes involved in sphingolipid biosynthesis- by myriocin and fumonisin B1, respectively, impaired phagocytosis by phagocytes. We used CRISPR/Cas9-mediated genome editing to generate Sptlc2-deficient DC2.4 dendritic cells, which lack serine palmitoyl transferase activity. Sptlc2-/- DC2.4 cells exhibited a stark defect in phagocytosis, were unable to bind fungal particles and failed to form a normal phagocytic cup to engulf C. albicans. Supplementing the growth media with GM1, the major ganglioside present at the cell surface, restored phagocytic activity of Sptlc2-/- DC2.4 cells. While overall membrane trafficking and endocytic pathways remained functional, Sptlc2-/- DC2.4 cells express reduced levels of the pattern recognition receptors Dectin-1 and TLR2 at the cell surface. Consistent with the in vitro data, compromised sphingolipid biosynthesis in mice sensitizes the animal to C. albicans infection. Sphingolipid biosynthesis is therefore critical for phagocytosis and in vivo clearance of C. albicans.

  8. Hydrophobic polyoxins are resistant to intracellular degradation in Candida albicans.

    PubMed Central

    Smith, H A; Shenbagamurthi, P; Naider, F; Kundu, B; Becker, J M

    1986-01-01

    Two novel polyoxins, N-epsilon-(octanoyl)-lysyl-uracil polyoxin C (Oct-Lys-UPOC) and N-gamma-(octyl)-glutaminyluracil polyoxin C (Oct-Gln-UPOC), were synthesized by reacting uracil polyoxin C with the appropriate amino acid p-nitrophenyl ester. Oct-Lys-UPOC and Oct-Gln-UPOC were strong inhibitors (Kis = 1.7 X 10(-6)M) of chitin synthetase from Candida albicans membrane preparations. In a permeabilized-cell assay, Oct-Gln-UPOC had a 10-fold-lower inhibitory activity toward chitin synthetase than did the Oct-Lys-UPOC analog. Both compounds were resistant to hydrolysis by a cell extract of C. albicans H317; however, Oct-Gln-UPOC was hydrolyzed with a half-life of 23 min by a permeabilized-cell preparation. Oct-Lys-UPOC was resistant to hydrolysis by permeabilized cells. Oct-Gln-UPOC and Oct-Lys-UPOC did not compete with the transport of peptides or uridine into the cell. At concentrations up to 2 mM these two new polyoxins were ineffective in the inhibition of cell growth or reduction of cell viability, but they induced aberrant morphologies in C. albicans at a concentration of 0.25 mM. These data suggest that polyoxins containing hydrophobic amino acids retain strong chitin synthetase inhibitory activity and are resistant to cellular hydrolysis. They provide the first example of effective synthetic chitin synthetase inhibitors which are stable inside C. albicans. PMID:3524423

  9. Zebrafish Egg Infection Model for Studying Candida albicans Adhesion Factors

    PubMed Central

    Chen, Yin-Zhi; Yang, Yun-Liang; Chu, Wen-Li; You, May-Su; Lo, Hsiu-Jung

    2015-01-01

    Disseminated candidiasis is associated with 30–40% mortality in severely immunocompromised patients. Among the causal agents, Candida albicans is the dominant one. Various animal models have been developed for investigating gene functions in C. albicans. Zebrafish injection models have increasingly been applied in elucidating C. albicans pathogenesis because of the conserved immunity, prolific fecundity of the zebrafish and the low costs of care systems. In this study, we established a simple, noninvasive zebrafish egg bath infection model, defined its optimal conditions, and evaluated the model with various C. albicans mutant strains. The deletion of SAP6 did not have significant effect on the virulence. By contrast, the deletion of BCR1, CPH1, EFG1, or TEC1 significantly reduced the virulence under current conditions. Furthermore, all embryos survived when co-incubated with bcr1/bcr1, cph1/cph1 efg1/efg1, efg1/efg1, or tec1/tec1 mutant cells. The results indicated that our novel zebrafish model is time-saving and cost effective. PMID:26569623

  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. Effect of 5-aminolevulinic acid photodynamic therapy on Candida albicans biofilms: An in vitro study.

    PubMed

    Shi, Hang; Li, Jiyang; Zhang, Hui; Zhang, Jie; Sun, Hongying

    2016-09-01

    In this study, the photoinactivation of 5-aminolevulinic acid (ALA) has been investigated on Candida albicans biofilms in vitro. After culture and proliferation of Candida albicans biofilms in vitro, the metabolic activity was confirmed using XTT reduction assay. Then, the suitable incubation time and concentration of ALA were determined by measuring PpIX accumulation quantities. Photosensitivity of the biofilms treated with ALA solution was studied in optical doses of 50, 100, 200 and 300J/cm(2) while light irradiation was applied by a red light semiconductor. Finally, rapid immunofluorescence staining method using the LIVE/DEAD FungaLight Yeast Viability Kit and XTT assay were conducted to visualize and quantify the antifungal effect of ALA-PDT on Candida albicans biofilms. A 5h incubation time and 15mM ALA concentration were determined for this study. Photoinactivation of ALA-PDT on Candida albicans biofilms showed a significant increase of protoporphyrin IX (PpIX) in the biofilms. The metabolic activity of Candida albicans biofilms tread with ALA-PDT confirmed the inhibition efficacy compared with control groups. Upon radiation at 300J/cm(2), cells in Candida albicans biofilms were 74.45% inhibited. PpIX can be absorbed in biofilm-grown Candida albicans in vitro and under appropriate parameters, photochemistry can be triggered by light in combination with ALA and inhibits Candida albicans biofilms effectively. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. 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.

  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. 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.

  16. Recent advances on Candida albicans biology and virulence

    PubMed Central

    Sellam, Adnane; Whiteway, Malcolm

    2016-01-01

    Candida albicans is an important human fungal pathogen, in terms of both its clinical significance and its use as an experimental model for scientific investigation. Although this opportunistic pathogen is a natural component of the human flora, it can cause life-threatening infections in immunosuppressed patients. There are currently a limited number of antifungal molecules and drug targets, and increasing resistance to the front-line therapeutics, demonstrating a clear need for new antifungal drugs. Understanding the biology of this pathogen is an important prerequisite for identifying new drug targets for antifungal therapeutics. In this review, we highlight some recent developments that help us to understand how virulence traits are regulated at the molecular level, in addition to technical advances that improve the ability of genome editing in C. albicans. PMID:27853524

  17. Glutathione protects Candida albicans against horseradish volatile oil.

    PubMed

    Bertóti, Regina; Vasas, Gábor; Gonda, Sándor; Nguyen, Nhat Minh; Szőke, Éva; Jakab, Ágnes; Pócsi, István; Emri, Tamás

    2016-10-01

    Horseradish essential oil (HREO; a natural mixture of different isothiocyanates) had strong fungicide effect against Candida albicans both in volatile and liquid phase. In liquid phase this antifungal effect was more significant than those of its main components allyl, and 2-phenylethyl isothiocyanate. HREO, at sublethal concentration, induced oxidative stress which was characterized with elevated superoxide content and up-regulated specific glutathione reductase, glutathione peroxidase, catalase and superoxide dismutase activities. Induction of specific glutathione S-transferase activities as marker of glutathione (GSH) dependent detoxification was also observed. At higher concentration, HREO depleted the GSH pool, increased heavily the superoxide production and killed the cells rapidly. HREO and the GSH pool depleting agent, 1-chlore-2,4-dinitrobenzene showed strong synergism when they were applied together to kill C. albicans cells. Based on all these, we assume that GSH metabolism protects fungi against isothiocyanates. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Recent advances on Candida albicans biology and virulence.

    PubMed

    Sellam, Adnane; Whiteway, Malcolm

    2016-01-01

    Candida albicans is an important human fungal pathogen, in terms of both its clinical significance and its use as an experimental model for scientific investigation. Although this opportunistic pathogen is a natural component of the human flora, it can cause life-threatening infections in immunosuppressed patients. There are currently a limited number of antifungal molecules and drug targets, and increasing resistance to the front-line therapeutics, demonstrating a clear need for new antifungal drugs. Understanding the biology of this pathogen is an important prerequisite for identifying new drug targets for antifungal therapeutics. In this review, we highlight some recent developments that help us to understand how virulence traits are regulated at the molecular level, in addition to technical advances that improve the ability of genome editing in C. albicans.

  19. Epidemiology of Candida isolates from Intensive Care Units in Colombia from 2010 to 2013.

    PubMed

    Motoa, Gabriel; Muñoz, Juan Sebastián; Oñate, José; Pallares, Christian José; Hernández, Cristhian; Villegas, María Virginia

    The frequency of Candida isolates as a cause of hospital infections has risen in recent years, leading to high rates of morbidity and mortality. The knowledge of the epidemiology of those hospital acquired fungal infections is essential to implement an adequate antifungal therapy. To describe the epidemiology of Candida infections in Intensive Care Units (ICUs) from a surveillance network in Colombia. Information was collected from the microbiology laboratories of 20 tertiary healthcare institutions from 10 Colombian cities using the Whonet® software version 5.6. A general descriptive analysis of Candida species and susceptibility profiles focusing on fluconazole and voriconazole was completed between 2010 and 2013, including a sub-analysis of healthcare associated infections (HAIs) during the last year. Candida isolates made up 94.5% of the 2680 fungal isolates considered, with similar proportions for Candida albicans and non-C. albicans Candida species (48.3% and 51.7%, respectively). Among the latter, Candida tropicalis (38.6%) and Candida parapsilosis (28.5%) were the most frequent species. Of note, among the blood isolates C. albicans was not the main species. Most of the species isolated were susceptible to fluconazole and voriconazole. From the HAIs reported, 25.5% were caused by Candida; central line-associated bloodstream infection was the most common HAI (58.8%). There were no statistically significant differences regarding length of hospital stay and device days among HAIs. In ICUs of Colombia, non-C. albicans Candida species are as frequent as C. albicans, except in blood samples where non-C. albicans Candida isolates predominate. Further studies are needed to evaluate Candida associated risk factors and to determine its clinical impact. Copyright © 2016 Asociación Española de Micología. Publicado por Elsevier España, S.L.U. All rights reserved.

  20. 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.

  1. Detection of myosin immunoanalogue in the yeast Candida albicans.

    PubMed

    Ghazali, M; Rodier, M H; el Moudni, B; Quellard, N; Jacquemin, J L

    1995-06-01

    Detection and localization of myosin immunoanalogue protein in the yeast Candida albicans were achieved by immunoblotting, indirect immunofluorescence assay, and immunoelectron microscopy. A polypeptide with an M(r) about 110,000, from cytosolic extract and insoluble fraction in the corresponding membrane pellet, was reacted with polyclonal and monoclonal antibodies raised against vertebrate muscle myosin. This protein was located by immunofluorescence and immunoelectron microscopy in the cell cortex along the plasmalemma, in the cytoplasm, and in the septum corresponding to bud scar region situated between the yeast-mother cell and the bud.

  2. Characterization of DNA topoisomerase I from Candida albicans as a target for drug discovery.

    PubMed Central

    Fostel, J M; Montgomery, D A; Shen, L L

    1992-01-01

    Candida albicans is an opportunistic pathogen responsible for life-threatening infections in persons with impaired immune systems. Topoisomerase I is a potential target for novel antifungal agents; however, in order for this enzyme to be a therapeutically useful target, it needs to be demonstrated that the fungal and human topoisomerases differ sufficiently as to allow the fungal topoisomerase to be selectively targeted. To address this question, we isolated the topoisomerase I from C. albicans and compared its biochemical properties with those of the mammalian enzyme. Similar to other eukaryotic type I topoisomerases, the C. albicans type I topoisomerase has an apparent molecular mass of 102 kDa and covalently links to the 3' end of DNA, as shown after the reaction is interrupted by sodium dodecyl sulfate. Topoisomerase poisons such as camptothecin act by stabilizing the cleavage complex formed by the topoisomerase I and DNA. We observed that the C. albicans and mammalian type I topoisomerases differ in that the C. albicans cleavage complex is approximately 10-fold less sensitive to camptothecin than the mammalian cleavage complex is. In addition, we found that the antifungal agent eupolauridine can stabilize the cleavage complex formed by both the C. albicans and human topoisomerases and that the response of the C. albicans topoisomerase I to this drug is greater than that of the human enzyme. Thus, the topoisomerase I from C. albicans is sufficiently distinct from the human enzyme as to allow differential chemical targeting and will therefore make a good target for antifungal drug discovery. Images PMID:1332588

  3. Antifungal effect of Trachyspermum ammi against susceptible and fluconazole-resistant strains of Candida albicans.

    PubMed

    Sharifzadeh, A; Khosravi, A R; Shokri, H; Sharafi, G

    2015-06-01

    Trachyspermum ammi (T. ammi) has been known as having many therapeutic properties and its antimicrobial activity has currently received a renewed interest. This study aimed to verify the effectiveness of T. ammi essential oil to inhibit the growth of Candida albicans (C. albicans) strains isolated from HIV(+) patients with oropharyngeal candidiasis (OPC). The essential oil was obtained by hydrodistillation in a Clevenger apparatus and analyzed by gas chromatography. Susceptibility tests were expressed as inhibition zone by the disk diffusion method and minimal inhibitory concentration (MIC) and minimal fungicidal concentration (MFC) by the broth microdilution method. Thymol (63.4%), p-cymene (19%) and γ-terpinen (16.9%) were found as the most abundant constituents. The disk diffusion results revealed that 67% of oral C. albicans isolates were susceptible, 9% susceptible-dose dependent and 24% resistant to fluconazole. In the broth microdilution method, 68% of isolates were susceptible, 5% susceptible-dose dependent and 27% resistant to fluconazole. The increase in concentration led to a significant reduction in yeasts that were growing in exponential phase. In addition, with increasing in T. ammi oil concentration, the time of remaining cells in lag phase was significantly increased. This study showed that all clinical C. albicans isolates were susceptible to T. ammi essential oil, indicating a significant reduction in the yeast growth in exponential phase. Copyright © 2015. Published by Elsevier Masson SAS.

  4. Candida detection system (CAND-TEC) to differentiate between Candida albicans colonization and disease.

    PubMed

    Fung, J C; Donta, S T; Tilton, R C

    1986-10-01

    Eighty-three serum specimens from 24 patients infected with Candida albicans were examined for circulating Candida protein antigens with the Candida Detection System (CAND-TEC; Ramco Laboratories, Inc., Houston, Tex.). The medical records of each patient were reviewed for clinical evidence of Candida colonization or disease, predisposing factors for infection, underlying illness, the presence of a contaminated indwelling venous catheter, intravenous amphotericin B therapy, and outcome. Forty-nine serum specimens with antigen titers of 1:2 or less were obtained either from colonized patients or at a time when disseminated disease was not yet clinically suspected. Except for five specimens from two colonized patients, one with a contaminated arterial line, the other specimens with titers of 1:8 or greater (n = 14) were obtained from patients who had been clinically diagnosed and treated for disseminated candidiasis. Serum specimens with titers of 1:4 were often from patients with deep-seated candidal infection but were not uniformly diagnostic; in this situation additional specimens should be tested for Candida antigen titers. Only 1 of 24 serum specimens from patients with no evidence of C. albicans infection had a Candida protein antigen titer of 1:8. With a 1:8 or greater titer as a criterion for dissemination, the sensitivity of the CAND-TEC