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Sample records for methanol yeast candida

  1. A new methanol assimilating yeast, Ogataea parapolymorpha, the ascosporic state of Candida parapolymorpha

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ogataea parapolymorpha sp. n. (NRRL YB-1982, CBS 12304, type strain), the ascosporic state of Candida parapolymorpha, is described. The species appears homothallic, assimilates methanol as is typical of most Ogataea species and forms hat-shaped ascospores in asci that become deliquescent. Ogataea pa...

  2. Molecular characterization of hap complex components responsible for methanol-inducible gene expression in the methylotrophic yeast Candida boidinii.

    PubMed

    Oda, Saori; Yurimoto, Hiroya; Nitta, Nobuhisa; Sasano, Yu; Sakai, Yasuyoshi

    2015-03-01

    We identified genes encoding components of the Hap complex, CbHAP2, CbHAP3, and CbHAP5, as transcription factors regulating methanol-inducible gene expression in the methylotrophic yeast Candida boidinii. We found that the Cbhap2Δ, Cbhap3Δ, and Cbhap5Δ gene-disrupted strains showed severe growth defects on methanol but not on glucose and nonfermentable carbon sources such as ethanol and glycerol. In these disruptants, the transcriptional activities of methanol-inducible promoters were significantly decreased compared to those of the wild-type strain, indicating that CbHap2p, CbHap3p, and CbHap5p play indispensable roles in methanol-inducible gene expression. Further molecular and biochemical analyses demonstrated that CbHap2p, CbHap3p, and CbHap5p localized to the nucleus and bound to the promoter regions of methanol-inducible genes regardless of the carbon source, and heterotrimer formation was suggested to be necessary for binding to DNA. Unexpectedly, distinct from Saccharomyces cerevisiae, the Hap complex functioned in methanol-specific induction rather than glucose derepression in C. boidinii. Our results shed light on a novel function of the Hap complex in methanol-inducible gene expression in methylotrophic yeasts.

  3. Characterization of a flavinogenic mutant of methanol yeast Candida boidinii and its extracellular secretion of riboflavin.

    PubMed

    Suryadi, H; Yoshida, N; Yamada-Onodera, K; Katsuragi, T; Tani, Y

    2000-01-01

    A flavinogenic mutant was derived from Candida boidinii by mutagenesis. The mutant was smaller than the wild type, did not grow on a minimal medium, and required l-tryptophan, l-leucine, inositol, and nicotinate for growth. The mutant was defective in the oxidative pentose phosphate pathway, lacking glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase. The specific activities of the transaldolase and transketolase of the mutant were higher than those of the wild type. These high activities might direct the flux of the carbon source to the nonoxidative pathway with formation of a large amount of pentose phosphates, increasing riboflavin synthesis. Under microaerobic conditions at 25 degrees C, 90 mg/l riboflavin was obtained. PMID:16232817

  4. Expression level of methanol-inducible peroxisomal proteins and peroxisome morphology are affected by oxygen conditions and mitochondrial respiratory pathway function in the methylotrophic yeast Candida boidinii.

    PubMed

    Fujimura, Shuki; Yurimoto, Hiroya; Kurimoto, Shota; Matsufuji, Yoshimi; Ito, Takashi; Hayakawa, Takashi; Tomizuka, Noboru; Sakai, Yasuyoshi; Nakagawa, Tomoyuki

    2013-06-01

    In the methylotrophic yeast, Candida boidinii, methanol-inducible peroxisomal proteins, for example alcohol oxidase (AOD), dihydroxyacetone synthase (DAS), and peroxisomal glutathione peroxidase (Pmp20), were induced only under aerobic conditions, while expression of PMP47 encoding peroxisomal integral membrane protein Pmp47 was independent of oxygen conditions. Expression of the methanol-inducible peroxisomal enzymes was repressed by inhibition of the mitochondrial respiratory chain. In the respiratory-deficient (ρ0) mutant strain, their induction was at very low levels despite the presence of oxygen, whereas the expression of PMP47 was unaffected. Taken together, these facts indicate that C. boidinii can sense oxygen conditions, and that mitochondrial respiratory function may have a profound effect on induction of methanol-inducible gene expression of peroxisomal proteins. Peroxisome morphology was also affected by oxygen conditions and respiratory function. Under hypoxic conditions or respiration-inhibited conditions, cells induced by methanol contained small peroxisomes, indicating that peroxisome biogenesis and the protein import machinery were not affected by oxygen conditions but that peroxisome morphology was dependent on induction of peroxisomal matrix proteins.

  5. Studies on methanol - oxidizing yeast. III. Enzyme.

    PubMed

    Volfová, O

    1975-01-01

    Oxidation of methanol, formaldehyde and formic acid was studied in cells and cell-free extract of the yeast Candida boidinii No. 11Bh. Methanol oxidase, an enzyme oxidizing methanol to formaldehyde, was formed inducibly after the addition of methanol to yeast cells. The oxidation of methanol by cell-free extract was dependent on the presence of oxygen and independent of any addition of nicotine-amide nucleotides. Temperature optimum for the oxidation of methanol to formaldehyde was 35 degrees C, pH optimum was 8.5. The Km for methanol was 0.8mM. The cell-free extract exhibited a broad substrate specificity towards primary alcohols (C1--C6). The activity of methanol oxidase was not inhibited by 1mM KCN, EDTA or monoiodoacetic acid. The strongest inhibitory action was exerted by p-chloromercuribenzoate. Both the cells and the cell-free extract contained catalase which participated in the oxidation of methanol to formaldehyde; the enzyme was constitutively formed by the yeast. The pH optimum for the degradation of H2O2 was in the same range as the optimum for methanol oxidation, viz. at 8.5. Catalase was more resistant to high pH than methanol oxidase. The cell-free extract contained also GSH-dependent NAD-formaldehyde dehydrogenase with Km = 0.29mM and NAD-formate dehydrogenase with Km = 55mM. PMID:240764

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

    PubMed

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

    2004-11-01

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

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

    PubMed

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

    2010-06-30

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

  8. 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

  9. Molecular epidemiology of Candida albicans and its closely related yeasts Candida dubliniensis and Candida africana.

    PubMed

    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.

  10. 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

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

    PubMed Central

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

    2016-01-01

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

  12. Recent Taxonomic Developments with Candida and Other Opportunistic Yeasts

    PubMed Central

    Lockhart, Shawn R.

    2015-01-01

    Increases in susceptible patient populations and advances in identification methods have resulted in the continued recognition of novel yeasts as agents of human infection. Most of these agents are members of the well-recognized genera Candida, Cryptococcus, Trichosporon, and Rhodotorula. Some of these agents are “cryptic species,” members of species complexes, and may not be detectable using classical carbohydrate assimilation-based methods of yeast identification. Such species require DNA- or MALDI-based methods for correct identification, although sporadic isolates may not routinely require delineation to the individual species level. The coming end of the fungal taxonomy rules requiring separate names for sexual and asexual forms of the same fungus will hopefully allow greater clarity, as names for medically important yeast can now be based on the needs of the medical mycology community and the common goal of better communication between laboratory and clinician. PMID:26526658

  13. Identification of Medically Important Candida and Non-Candida Yeast Species by an Oligonucleotide Array▿

    PubMed Central

    Leaw, Shiang Ning; Chang, Hsien Chang; Barton, Richard; Bouchara, Jean-Philippe; Chang, Tsung Chain

    2007-01-01

    The incidence of yeast infections has increased in the recent decades, with Candida albicans still being the most common cause of infections. However, infections caused by less common yeasts have been widely reported in recent years. Based on the internal transcribed spacer 1 (ITS 1) and ITS 2 sequences of the rRNA genes, an oligonucleotide array was developed to identify 77 species of clinically relevant yeasts belonging to 16 genera. The ITS regions were amplified by PCR with a pair of fungus-specific primers, followed by hybridization of the digoxigenin-labeled PCR product to a panel of oligonucleotide probes immobilized on a nylon membrane for species identification. A collection of 452 yeast strains (419 target and 33 nontarget strains) was tested, and a sensitivity of 100% and a specificity of 97% were obtained by the array. The detection limit of the array was 10 pg of yeast genomic DNA per assay. In conclusion, yeast identification by the present method is highly reliable and can be used as an alternative to the conventional identification methods. The whole procedure can be finished within 24 h, starting from isolated colonies. PMID:17507521

  14. 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

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

    PubMed

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

    2007-12-01

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

  16. Description of Kuraishia piskuri f.a., sp. nov., a new methanol assimilating yeast and transfer of phylogenetically related Candida species to the genera Kuraishia and Nakazawaea as new combinations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The new anamorphic yeast Kuraishia piskuri, f.a., sp. nov. is described for three strains that were isolated from insect frass from trees growing in Florida, USA (type strain, NRRL YB-2544, CBS 13714). Species placement was based on phylogenetic analysis of nuclear gene sequences for the D1/D2 domai...

  17. Five novel Candida species in insect-associated yeast clades isolated from Neuroptera and other insects.

    PubMed

    Nguyen, Nhu H; Suh, Sung-Oui; Blackwell, Meredith

    2007-01-01

    Ascomycete yeasts are found commonly in the guts of basidioma-feeding beetles but little is known about their occurrence in the gut of other insects. In this study we isolated 95 yeasts from the gut of adult insects in five neuropteran families (Neuroptera: Corydalidae, Chrysopidae, Ascalaphidae, Mantispidae and Hemerobiidae) and a roach (Blattodea: Blattidae). Based on DNA sequence comparisons and other taxonomic characteristics, they were identified as more than 15 species of Saccharomycetes as well as occasional Cryptococcus-like basidiomycete yeasts. Yeast species such as Lachancea fermentati, Lachancea thermotolerans and Hanseniaspora vineae were isolated repeatedly from the gut of three species of corydalids, suggesting a close association of these species and their insect hosts. Among the yeasts isolated in this study 12 were identified as five novel Candida species that occurred in three phylogenetically distinct clades. Molecular phylogenetic analyses showed that Candida chauliodes sp. nov. (NRRL Y-27909T) and Candida corydali sp. nov. (NRRL Y-27910T) were sister taxa in the Candida albicans/ Lodderomyces elongisporus clade. Candida dosseyi sp. nov. (NRRL Y-27950T) and Candida blattae sp. nov. (NRRL Y-27698T) were sister taxa in the Candida intermedia clade. Candida ascalaphidarum sp. nov. (NRRL Y-27908T) fell on a basal branch in a clade containing Candida membranifaciens and many other insect-associated species. Descriptions of these novel yeast species are provided as well as discussion of their ecology in relation to their insect hosts.

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

    PubMed Central

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

    2002-01-01

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

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

    PubMed

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

    2015-10-01

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

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

    PubMed

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

    2006-05-01

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

  1. Regulation of nitrate and methylamine metabolism by multiple nitrogen sources in the methylotrophic yeast Candida boidinii.

    PubMed

    Shiraishi, Kosuke; Oku, Masahide; Uchida, Daichi; Yurimoto, Hiroya; Sakai, Yasuyoshi

    2015-11-01

    The methylotrophic yeast Candida boidinii, which is capable of growth on methanol as a sole carbon source, can proliferate on the leaf surface of Arabidopsis thaliana. Previously, we demonstrated that adaptation to a change in the major available nitrogen source from nitrate to methylamine during the host plant aging was crucial for yeast survival on the leaf environment. In this report, we investigated the regulatory profile of nitrate and methylamine metabolism in the presence of multiple nitrogen sources in C. boidinii. The transcript level of nitrate reductase (Ynr1) gene was induced by nitrate and nitrite, and was not repressed by the coexistence with other nitrogen sources. In contrast, the transcript level of amine oxidase (Amo1) gene, which was induced by methylamine, was significantly repressed by the coexistence with ammonium or glutamine. In addition, we investigated the intracellular dynamics of Ynr1 during the nitrogen source shift from nitrate to other compounds. Under these tested conditions, Ynr1 was effectively transported to the vacuole via selective autophagy only during the shift from nitrate to methylamine. Moreover, Ynr1 was subject to degradation after the shift from nitrate to nitrate plus methylamine medium even though nitrate was still available. These regulatory profiles may reflect life style of nitrogen utilization in this yeast living in the phyllosphere.

  2. Regulation of nitrate and methylamine metabolism by multiple nitrogen sources in the methylotrophic yeast Candida boidinii.

    PubMed

    Shiraishi, Kosuke; Oku, Masahide; Uchida, Daichi; Yurimoto, Hiroya; Sakai, Yasuyoshi

    2015-11-01

    The methylotrophic yeast Candida boidinii, which is capable of growth on methanol as a sole carbon source, can proliferate on the leaf surface of Arabidopsis thaliana. Previously, we demonstrated that adaptation to a change in the major available nitrogen source from nitrate to methylamine during the host plant aging was crucial for yeast survival on the leaf environment. In this report, we investigated the regulatory profile of nitrate and methylamine metabolism in the presence of multiple nitrogen sources in C. boidinii. The transcript level of nitrate reductase (Ynr1) gene was induced by nitrate and nitrite, and was not repressed by the coexistence with other nitrogen sources. In contrast, the transcript level of amine oxidase (Amo1) gene, which was induced by methylamine, was significantly repressed by the coexistence with ammonium or glutamine. In addition, we investigated the intracellular dynamics of Ynr1 during the nitrogen source shift from nitrate to other compounds. Under these tested conditions, Ynr1 was effectively transported to the vacuole via selective autophagy only during the shift from nitrate to methylamine. Moreover, Ynr1 was subject to degradation after the shift from nitrate to nitrate plus methylamine medium even though nitrate was still available. These regulatory profiles may reflect life style of nitrogen utilization in this yeast living in the phyllosphere. PMID:26377403

  3. Production of flavin mononucleotide by metabolically engineered yeast Candida famata.

    PubMed

    Yatsyshyn, Valentyna Y; Ishchuk, Olena P; Voronovsky, Andriy Y; Fedorovych, Daria V; Sibirny, Andriy A

    2009-05-01

    Recombinant strains of the flavinogenic yeast Candida famata able to overproduce flavin mononucleotide (FMN) that contain FMN1 gene encoding riboflavin (RF) kinase driven by the strong constitutive promoter TEF1 (translation elongation factor 1alpha) were constructed. Transformation of these strains with the additional plasmid containing the FMN1 gene under the TEF1 promoter resulted in the 200-fold increase in the riboflavin kinase activity and 100-fold increase in FMN production as compared to the wild-type strain (last feature was found only in iron-deficient medium). Overexpression of the FMN1 gene in the mutant that has deregulated riboflavin biosynthesis pathway and high level of riboflavin production in iron-sufficient medium led to the 30-fold increase in the riboflavin kinase activity and 400-fold increase in FMN production of the resulted transformants. The obtained C. famata recombinant strains can be used for the further construction of improved FMN overproducers. PMID:19558965

  4. [Evaluation of Vitek 2 for the identification of Candida yeasts].

    PubMed

    Ochiuzzi, María E; Cataldi, Silvana; Guelfand, Liliana; Maldonado, Ivana; Arechavala, Alicia

    2014-01-01

    The aim of this investigation was to evaluate the performance of Vitek 2 YST cards (bioMérieux, Inc., Hazelwood, MO, USA) for the identification of yeasts of the genus Candida. A total of 168 isolates were analyzed and the results were compared to those of the API 20 C AUX (24%) o API ID 32 C (76%) kits (bioMérieux, Marcy L'Etoile, France). Each isolate was grown in chromogenic agar and in corn meal agar (Oxoid, UK) to observe its micromorphology. C. albicans and C. dublininesis were identified by additional biochemical and molecular tests. The agreement observed was 98.3%. Only three isolates were incorrectly identified by Vitek 2: one strain of C .tropicalis and one strain of C. krusei were identified as C. parapsilosis by YST while one strain of C. krusei was identified with low discrimination. The average time for obtaining results was 18.25 h. Vitek 2 is a simple, safe and useful system for the identification of significant Candida species.

  5. [Evaluation of Vitek 2 for the identification of Candida yeasts].

    PubMed

    Ochiuzzi, María E; Cataldi, Silvana; Guelfand, Liliana; Maldonado, Ivana; Arechavala, Alicia

    2014-01-01

    The aim of this investigation was to evaluate the performance of Vitek 2 YST cards (bioMérieux, Inc., Hazelwood, MO, USA) for the identification of yeasts of the genus Candida. A total of 168 isolates were analyzed and the results were compared to those of the API 20 C AUX (24%) o API ID 32 C (76%) kits (bioMérieux, Marcy L'Etoile, France). Each isolate was grown in chromogenic agar and in corn meal agar (Oxoid, UK) to observe its micromorphology. C. albicans and C. dublininesis were identified by additional biochemical and molecular tests. The agreement observed was 98.3%. Only three isolates were incorrectly identified by Vitek 2: one strain of C .tropicalis and one strain of C. krusei were identified as C. parapsilosis by YST while one strain of C. krusei was identified with low discrimination. The average time for obtaining results was 18.25 h. Vitek 2 is a simple, safe and useful system for the identification of significant Candida species. PMID:25011593

  6. The yeast community of sap fluxes of Costa Rican Maclura (Chlorophora) tinctoria and description of two new yeast species, Candida galis and Candida ortonii.

    PubMed

    Lachance, M A; Klemens, J A; Bowles, J M; Janzen, D H

    2001-07-01

    We report on the yeast community associated with sap fluxes of Maclura tinctoria, family Moraceae, in the dry forest of the Area de Conservación Guanacaste, Costa Rica. Eleven samples yielded seven hitherto undescribed ascomycetous yeasts in the genera Candida and Myxozyma. We describe the two most abundant as new species. Candida galis utilizes very few carbon compounds limited to some alcohols and acids. Analysis of rDNA sequences suggests that it occupies a basal position with respect to the Pichia anomala clade, with no obvious sister species. Candida ortonii is also restricted in nutritional breadth, and growth is generally very slow. It is a sister species to Candida nemodendra. The type cultures are: C. galis, strain UWO(PS)00-159.2=CBS 8842; and C. ortonii, strain UWO(PS)00-159.3=CBS 8843.

  7. Species identification of invasive yeasts including Candida in Pakistan: limitations of phenotypic methods

    PubMed Central

    Farooqi, Joveria; Jabeen, Kauser; Saeed, Noureen; Zafar, Afia; Brandt, Mary Eleanor; Hasan, Rumina

    2015-01-01

    Objective To compare phenotypic and genotypic methods of yeast identification. Methods The in-vitro cross-sectional study was conducted from January 2006 to May 2009. Invasive yeasts isolated at the clinical microbiology laboratory at the Aga Khan University (AKU), Karachi, Pakistan, were identified. Speciation by phenotypic and molecular methods was compared. All yeasts isolated during the study period from blood and other invasive sites were identified using standard methods. Isolates were shipped to Mycotic Diseases Branch, Centres for Disease Control and Prevention, Atlanta, Georgia, USA, for identification by Luminex flow cytometric multianalyte profiling (xMAP) system. Ribosomal ITS2 DNA sequencing was performed on isolates not identified by Luminex. Result Of the 214 invasive yeasts evaluated, Candida species were 209 (97.7%) while the frequency of non-Candida species was 5 (2.3%). Overall agreement between phenotypic and molecular identification was 81.3%, 90.3% amongst the more common Candida species, and only 38.8% amongst the uncommon yeasts. Conclusion Phenotypic methods of identification proved adequate for common Candida species, but were deficient in recognising rare Candida and non-Candida yeasts, highlighting the importance of molecular methods for identification. PMID:23866432

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

    SciTech Connect

    Toivola, A.; Yarrow, D.; van den Bosch, E.; van Dijken, J.P.; Scheffers, W.A.

    1984-06-01

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

  9. In vitro antifungal activity of fluconazole and voriconazole against non-Candida yeasts and yeast-like fungi clinical isolates.

    PubMed

    Mandras, Narcisa; Roana, Janira; Scalas, Daniela; Fucale, Giacomo; Allizond, Valeria; Banche, Giuliana; Barbui, Anna; Li Vigni, Nicolò; Newell, Vance A; Cuffini, Anna Maria; Tullio, Vivian

    2015-10-01

    The risk of opportunistic infections caused by non-Candida yeasts and yeast-like fungi is increasingly common, mainly in immunocompromised patients. Appropriate first-line therapy has not been defined and standardized, mainly due to the low number of cases reported. To improve empirical treatment guidelines, we describe the susceptibility profile to fluconazole and voriconazole of 176 non-Candida yeasts and yeast-like fungi collected from hospitals in Piedmont, North West Italy from January 2009 to December 2013. The results showed that most isolates are susceptible to voriconazole (94%), but less susceptible to fluconazole (78%), suggesting that voriconazole could be used as first-line therapy in infections caused by these fungi.

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

    PubMed Central

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

    2011-01-01

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

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

    PubMed Central

    Yücesoy, Mine; Marol, Serhat

    2003-01-01

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

  12. [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.

  13. Evaluation of the Yeast Traffic Light PNA FISH Probes for Identification of Candida Species from Positive Blood Cultures

    PubMed Central

    Hall, Leslie; Le Febre, Kara M.; Deml, Sharon M.; Wohlfiel, Sherri L.

    2012-01-01

    The Yeast Traffic Light PNA FISH kit (YTL) correctly identified Candida spp. in 207/216 (96%) positive blood cultures. Discordant results were seen with known cross-reacting species and cultures containing Candida lambica and Rhodotorula mucilaginosa. The YTL provides rapid, reliable identification of the five common Candida species found in blood cultures. PMID:22238445

  14. Evaluation of the Yeast Traffic Light PNA FISH probes for identification of Candida species from positive blood cultures.

    PubMed

    Hall, Leslie; Le Febre, Kara M; Deml, Sharon M; Wohlfiel, Sherri L; Wengenack, Nancy L

    2012-04-01

    The Yeast Traffic Light PNA FISH kit (YTL) correctly identified Candida spp. in 207/216 (96%) positive blood cultures. Discordant results were seen with known cross-reacting species and cultures containing Candida lambica and Rhodotorula mucilaginosa. The YTL provides rapid, reliable identification of the five common Candida species found in blood cultures.

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

    PubMed Central

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

    2014-01-01

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

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

    PubMed

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

    2016-01-01

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

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

    PubMed Central

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

    2016-01-01

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

  18. Killer toxin from several food-derived Debaryomyces hansenii strains effective against pathogenic Candida yeasts.

    PubMed

    Banjara, Nabaraj; Nickerson, Kenneth W; Suhr, Mallory J; Hallen-Adams, Heather E

    2016-04-01

    Candida yeasts are the dominant fungi in the healthy human microbiome, but are well-known for causing disease following a variety of perturbations. Evaluation of fungal populations from the healthy human gut revealed a significant negative correlation between the foodborne yeast, Debaryomyces hansenii, and Candida species. D. hansenii is reported to produce killer toxins (mycocins) effective against other yeast species. In order to better understand this phenomenon, a collection of 42 D. hansenii isolates was obtained from 22 cheeses and evaluated for killer activity against Candida albicans and Candida tropicalis over a range of temperatures and pH values. Twenty three strains demonstrated killer activity against both C. albicans and C. tropicalis, which was pH- and temperature-dependent, with no killer activity observed for any strain at pH6.5 or higher, or at ≥ 35 °C (physiological conditions in the human gastrointestinal tract). A cell-free mycocin preparation showed transient killer activity against C. albicans at 35 °C and a cheese sample containing a killer D. hansenii strain demonstrated sustained killer activity against both C. albicans and C. tropicalis. Together, these observations raise the possibility that D. hansenii could influence Candida populations in the gut.

  19. [Current aspects of invasive diseases caused by Candida and other yeast fungi].

    PubMed

    Pemán, Javier; Quindós, Guillermo

    2016-01-01

    Invasive candidiasis is the most common invasive fungal disease causing an unacceptably high mortality. Candida albicans remains the predominant origin, but an epidemiological shift has been described in the last decades. Some species of Candida have emerged as an important cause of severe candidaemia and can exhibit reduced susceptibility to the current antifungal agents. Candida parapsilosis has been associated with candidaemia in neonates and young adults, whereas Candida glabrata, Candida tropicalis, and Candida krusei are most frequently isolated in blood cultures from older patients (>65 years). Other yeasts are becoming important causes of invasive mycoses, such as Cryptococcus, Trichosporon, Malassezia, Geotrichum or Saprochaete/Magnusiomyces. Cryptococcosis is more relevant as a cause of meningitis in HIV-infected people, but cryptococcal infections are also a clinical challenge in transplant recipients. Diagnosis remains an important problem, causing unacceptable delays in starting a correct and direct treatment. However, there are some new approaches that can help in the prompt and specific diagnosis of invasive yeast infections, such as in situ hybridisation using PNA-FISH probes, causal agent identification in blood cultures using MALDi-TOF MS, or new and rapid nucleic acids detection assays.

  20. CHROMagar Candida Medium for Direct Susceptibility Testing of Yeast from Blood Cultures

    PubMed Central

    Tan, Grace L.; Peterson, Ellena M.

    2005-01-01

    An evaluation was performed on 95 blood cultures positive for Candida spp. to determine the correlation of direct susceptibility testing of fluconazole versus both standardized disk diffusion and MIC methods. For direct testing, an aliquot taken from BD BACTEC Plus and/or BD BACTEC Lytic/10 bottles (Becton Dickinson [BD], Sparks, MD) positive by gram stain for yeast was subcultured to CHROMagar Candida (BD), and a 25-μg fluconazole disk (BD) was placed on the plate. The area of growth inhibition surrounding the disk was measured at 24 and 48 h. In addition, a subculture of the isolate was tested by a microdilution MIC using YeastOne (TREK Diagnostics Systems Inc., OH) and disk diffusion (NCCLS M44-A) using a standardized inoculum plated onto CHROMagar Candida as well as Mueller-Hinton agar to which 2% glucose and 0.5 μg/ml methylene blue dye was added (MH-GMB). The categorical interpretation derived from the MIC was used as the reference to which the disk diffusion results were compared. There were a total of 41 Candida albicans, 23 Candida glabrata, 20 Candida parapsilosis, 9 Candida tropicalis, and 1 each of Candida krusei and Candida lusitaniae tested. At 24 h there was full agreement among the methods for all C. albicans, C. tropicalis, C. lusitaniae, and C. krusei isolates. For the C. parapsilosis isolates at 24 h there was one very major discrepancy using the direct CHROMagar and one major error with the standardized MH-GMB. The majority of the errors were seen at 24 h with the C. glabrata isolates. Of the 23 C. glabrata isolates at 24 h by direct CHROMagar, there were 10 minor and 1 very major error; by MH-GMB there were 12 minor and 2 very major errors; and by standardized CHROMagar Candida there were 13 minor and 2 major errors. There were no very major errors with C. glabrata when all plates were read at 48 h. At 24 h by the direct and standardized CHROMagar the majority of C. glabrata isolates were more resistant, whereas by MH-GMB they were more

  1. Growth kinetic model that describes the inhibitory and lytic effects of phenol on Candida tropicalis yeast.

    PubMed

    Ruiz-Ordaz, N; Hernández-Manzano, E; Ruiz-Lagúnez, J C; Cristiani-Urbina, E; Galíndez-Mayer, J

    1998-01-01

    The object of this work was to carry out a kinetic study on the Candida tropicalis cell lysis and to obtain a kinetic model that would describe the inhibitory and lytic effects of phenol on the yeast growth. From the experiments, a model for the growth kinetic behavior of the yeast was evolved. The proposed model describes satisfactorily the inhibitory and lytic effects of phenol on yeast cultures. From the kinetic model constants, it was found that C. tropicalis showed high affinity and tolerance toward phenol. The overall growth yields decreased when the initial phenol concentration increased, and it may be due to an increased maintenance coefficient and to cell lysis.

  2. Vacuoles of Candida yeast as a specialized niche for Helicobacter pylori

    PubMed Central

    Siavoshi, Farideh; Saniee, Parastoo

    2014-01-01

    Helicobacter pylori (H. pylori) are resistant to hostile gastric environments and antibiotic therapy, reflecting the possibility that they are protected by an ecological niche, such as inside the vacuoles of human epithelial and immune cells. Candida yeast may also provide such an alternative niche, as fluorescently labeled H. pylori were observed as fast-moving and viable bacterium-like bodies inside the vacuoles of gastric, oral, vaginal and foodborne Candida yeasts. In addition, H. pylori-specific genes and proteins were detected in samples extracted from these yeasts. The H. pylori present within these yeasts produce peroxiredoxin and thiol peroxidase, providing the ability to detoxify oxygen metabolites formed in immune cells. Furthermore, these bacteria produce urease and VacA, two virulence determinants of H. pylori that influence phago-lysosome fusion and bacterial survival in macrophages. Microscopic observations of H. pylori cells in new generations of yeasts along with amplification of H. pylori-specific genes from consecutive generations indicate that new yeasts can inherit the intracellular H. pylori as part of their vacuolar content. Accordingly, it is proposed that yeast vacuoles serve as a sophisticated niche that protects H. pylori against the environmental stresses and provides essential nutrients, including ergosterol, for its growth and multiplication. This intracellular establishment inside the yeast vacuole likely occurred long ago, leading to the adaptation of H. pylori to persist in phagocytic cells. The presence of these bacteria within yeasts, including foodborne yeasts, along with the vertical transmission of yeasts from mother to neonate, provide explanations for the persistence and propagation of H. pylori in the human population. This Topic Highlight reviews and discusses recent evidence regarding the evolutionary adaptation of H. pylori to thrive in host cell vacuoles. PMID:24833856

  3. Vacuoles of Candida yeast as a specialized niche for Helicobacter pylori.

    PubMed

    Siavoshi, Farideh; Saniee, Parastoo

    2014-05-14

    Helicobacter pylori (H. pylori) are resistant to hostile gastric environments and antibiotic therapy, reflecting the possibility that they are protected by an ecological niche, such as inside the vacuoles of human epithelial and immune cells. Candida yeast may also provide such an alternative niche, as fluorescently labeled H. pylori were observed as fast-moving and viable bacterium-like bodies inside the vacuoles of gastric, oral, vaginal and foodborne Candida yeasts. In addition, H. pylori-specific genes and proteins were detected in samples extracted from these yeasts. The H. pylori present within these yeasts produce peroxiredoxin and thiol peroxidase, providing the ability to detoxify oxygen metabolites formed in immune cells. Furthermore, these bacteria produce urease and VacA, two virulence determinants of H. pylori that influence phago-lysosome fusion and bacterial survival in macrophages. Microscopic observations of H. pylori cells in new generations of yeasts along with amplification of H. pylori-specific genes from consecutive generations indicate that new yeasts can inherit the intracellular H. pylori as part of their vacuolar content. Accordingly, it is proposed that yeast vacuoles serve as a sophisticated niche that protects H. pylori against the environmental stresses and provides essential nutrients, including ergosterol, for its growth and multiplication. This intracellular establishment inside the yeast vacuole likely occurred long ago, leading to the adaptation of H. pylori to persist in phagocytic cells. The presence of these bacteria within yeasts, including foodborne yeasts, along with the vertical transmission of yeasts from mother to neonate, provide explanations for the persistence and propagation of H. pylori in the human population. This Topic Highlight reviews and discusses recent evidence regarding the evolutionary adaptation of H. pylori to thrive in host cell vacuoles.

  4. Early differential molecular response of a macrophage cell line to yeast and hyphal forms of Candida albicans.

    PubMed Central

    Blasi, E; Pitzurra, L; Puliti, M; Lanfrancone, L; Bistoni, F

    1992-01-01

    The dimorphic transition of Candida albicans from the yeast (Y-Candida) to the hyphal (H-Candida) form is a complex event; the relevance of this transition in fungal pathogenicity is still poorly understood. By using a cloned macrophage cell line (ANA-1), we questioned whether the interaction between macrophages and Y-Candida or H-Candida could affect specific cell functions, i.e., tumor necrosis factor and lysozyme production. We found that ANA-1 macrophages selectively responded to H-Candida with increased tumor necrosis factor and downregulated lysozyme, as assessed by measurement of relative mRNA levels and secreted biological activities. The H-Candida-mediated effects were (i) dependent upon the ratio between ANA-1 macrophages and H-Candida, (ii) detectable after 1 h of coincubation, and (iii) accomplished without fungal ingestion. Conversely, Y-Candida, which was found inside the ANA-1 macrophages, did not affect tumor necrosis factor and lysozyme production, nor did it prevent the macrophage response to other stimuli. Overall, these results indicate that a macrophage can distinguish between Y-Candida and H-Candida and that only the latter is able to modulate specific functions. H-Candida is recognized and probably processed as an extracellular target. The possible implication of macrophages as autocrine and paracrine regulatory cells during Candida infections is discussed. Images PMID:1541557

  5. Candida middelhoveniana sp. nov., a new yeast species found on the rhizoplane of organically cultivated sugarcane.

    PubMed

    Ribeiro, José R de A; Carvalho, Patrícia M B de; Cabral, Anderson de S; Macrae, Andrew; Mendonça-Hagler, Leda C S; Berbara, Ricardo L L; Hagler, Allen N

    2011-10-01

    A novel yeast species within the Metschnikowiaceae is described based on a strain from the sugarcane (Saccharum sp.) rhizoplane of an organically managed farm in Rio de Janeiro, Brazil. The D1/D2 domain of the large subunit ribosomal RNA gene sequence analysis showed that the closest related species were Candida tsuchiyae with 86.2% and Candida thailandica with 86.7% of sequence identity. All three are anamorphs in the Clavispora opuntiae clade. The name Candida middelhoveniana sp. nov. is proposed to accommodate this highly divergent organism with the type strain Instituto de Microbiologia, Universidade Federal do Rio de Janeiro (IMUFRJ) 51965(T) (=Centraalbureau voor Schimmelcultures (CBS) 12306(T), Universidade Federal de Minas Gerais (UFMG)-70(T), DBVPG 8031(T)) and the GenBank/EMBL/DDBJ accession number for the D1/D2 domain LSU rDNA sequence is FN428871. The Mycobank deposit number is MB 519801.

  6. Biosensor analyzer for BOD index express control on the basis of the yeast microorganisms Candida maltosa, Candida blankii, and Debaryomyces hansenii.

    PubMed

    Arlyapov, Viacheslav; Kamanin, Stanislav; Ponamoreva, Olga; Reshetilov, Anatoly

    2012-04-01

    The parameters of biosensors based on the yeast strains Candida maltosa VKM Y-2359, Candida blankii VKM Y-2675, and Debaryomyces hansenii VKM Y-2482 for biochemical oxygen demand (BOD) detection are compared. The catalytic activity of the strains was analyzed in relation to the growth phase. The possibility of using D. hansenii as a basis for receptor element of a biosensor for BOD detection in municipal and biotechnological wastewaters was shown.

  7. [The effect of sodium azide on the thermotolerance of the yeast Saccharomyces cerevisiae and Candida albicans].

    PubMed

    Rikhvanov, E G; Varakina, N N; Rusaleva, T M; Rachenko, E I; Voĭnikov, V K

    2002-01-01

    The addition of sodium azide (a mitochondrial inhibitor) at a concentration of 0.15 mM to glucosegrown Saccharomyces cerevisiae or Candida albicans cells before exposing them to heat shock increased cell survival. At higher concentrations of azide, its protective effect on glucose-grown cells decreased. Furthermore, azide, even at low concentrations, diminished the thermotolerance of galactose-grown yeast cells. It is suggested that azide exerts a protective effect on the thermotolerance of yeast cells when their energy requirements are met by the fermentation of glucose. However, when cells obtain energy through respiratory metabolism, the azide inhibition of mitochondria enhances damage inflicted on the cells by heat shock.

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

    PubMed

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

    2015-06-01

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

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

    SciTech Connect

    Shen, H.D.; Choo, K.B.; Tsai, W.C.; Jen, T.M.; Yeh, J.Y.; Han, S.H.

    1988-12-01

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

  10. Ogataea saltuana sp. nov., a novel methanol-assimilating yeast species

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Four ascosporulating strains of an undescribed methanol-assimilating yeast species were isolated from forest habitats in Hungary. Three of them were recovered from rotten wood and one from leaves of a sessile oak. A closely related, but somewhat divergent strain was recovered from insect frass in a ...

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

    PubMed Central

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

    1996-01-01

    Two chromogenic media, Albicans ID and CHROMagar Candida agar plates, were compared with a reference medium, Sabouraud-chloramphenicol agar, and standard methods for the identification of yeast species. This study involved 951 clinical specimens. The detection rates for the two chromogenic media for polymicrobial specimens were 20% higher than that for the Sabouraud-chloramphenicol agar plates. The rates of identification of Candida albicans for Albicans ID and CHROMagar Candida agar plates were, respectively, 37.0 and 6.0% after 24 h of incubation and 93.6 and 92.2% after 72 h of incubation, with specificities of 99.8 and 100%. Furthermore, CHROMagar Candida plates identified 13 of 14 Candida tropicalis and 9 of 12 Candida krusei strains after 48 h of incubation. PMID:8789038

  12. Aging and Cell Death in the Other Yeasts, Schizosaccharomyces pombe and Candida albicans

    PubMed Central

    Lin, Su-Ju; Austriaco, Nicanor

    2013-01-01

    How do cells age and die? For the past twenty years, the budding yeast, Saccharomyces cerevisiae, has been used as a model organism to uncover the genes that regulate lifespan and cell death. More recently, investigators have begun to interrogate the other yeasts, the fission yeast, Schizosaccharomyces pombe, and the human fungal pathogen, Candida albicans, to determine if similar longevity and cell death pathways exist in these organisms. After summarizing the longevity and cell death phenotypes in S. cerevisiae, this mini-review surveys the progress made in the study of both aging and programmed cell death (PCD) in the yeast models, with a focus on the biology of S. pombe and C. albicans. Particular emphasis is placed on the similarities and differences between the two types of aging, replicative aging and chronological aging, and between the three types of cell death, intrinsic apoptosis, autophagic cell death, and regulated necrosis, found in these yeasts. The development of the additional microbial models for aging and PCD in the other yeasts may help further elucidate the mechanisms of longevity and cell death regulation in eukaryotes. PMID:24205865

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

    PubMed

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

    2010-01-01

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

  14. Identification of Candida species and susceptibility testing with Sensititre YeastOne microdilution panel to 9 antifungal agents

    PubMed Central

    Kucukates, Emine; Gultekin, Nuh N.; Alisan, Zeynep; Hondur, Nur; Ozturk, Recep

    2016-01-01

    Objectives: To determine the species incidence and susceptibility pattern to 9 antifungal agents of yeasts isolated from various clinical specimens of colonized or infected patients treated in the coronary and surgical intensive care units (ICU). Methods: A total of 421 ICU patients were treated at the Cardiology Institute, Istanbul University, Istanbul, Turkey between June 2013 and May 2014, and 44 Candida species were isolated from blood, urine, endotracheal aspiration fluid, sputum, and wounds of 16 ICU patients. Identification of Candida was performed using CHROMagar. Antifungal susceptibility was determined by a Sensititre YeastOne colorimetric microdilution panel. Results: Candida albicans (C. albicans) was the most commonly observed microorganism 23 (54%); the other microorganisms isolated were Candida tropicalis 12 (27%), Candida glabrata 5 (11%), Candida parapsilosis 1 (2%), Candida lusitaniae 1 (2%), Candida sake 1 (2%), and Geotrichum capitatum 1 (2%). All isolates were susceptible to amphotericin B and 5-flucytosine. Geotrichum capitatum excepted, the other isolates were also susceptible to anidulafungin, micafungin, and caspofungin. Candida parapsilosis was found to be susceptible to all the studied antifungals. High MIC rates for azole group of antifungal drugs were found for C. albicans, C. tropicalis, and C. glabrata. The rate of colonisation was 3.8% (16/421). Only 0.7% (3/421) patients out of a total of 421 developed candidemia. Conclusion: We found that the yeast colonization and infection rates of patients in our ICUs are very low. Candida albicans is still the most common species. We detected a decreasing susceptibility to azole compounds. PMID:27381534

  15. Stress tolerance and biocontrol performance of the yeast antagonist, Candida diversa, change with morphology transition.

    PubMed

    Li, Guangkun; Chi, Mengshan; Chen, Huizhen; Sui, Yuan; Li, Yan; Liu, Yongsheng; Zhang, Xiaojing; Sun, Zhiqiang; Liu, Guoqing; Wang, Qi; Liu, Jia

    2016-02-01

    As an eco-friendly management method, biological control of postharvest diseases, utilizing antagonistic yeasts, is a research topic receiving considerable attention. Detailed knowledge on the biology of yeast antagonists is crucial when considering their potential application and development as biocontrol products. Changes in the growth form, such as single-cell to pseudohyphae, have been associated with the mode of action in postharvest biocontrol yeasts. In this study, the antagonistic yeast, Candida diversa, reversibly shifted from a single-cell morphology on yeast peptone dextrose (YPD) medium with 2 % agar to a pseudohyphal morphology on YPD with 0.3 % agar. The tolerance of the pseudohyphal form to heat and oxidative stresses, as well as the biocontrol efficacy against Botrytis cinerea on apple and kiwifruit stored at 25 and 4 °C, was significantly higher as compared to the single-cell form. This study provides new information on the ability of C. diversa to change its morphology and the impact of the morphology shift on stress tolerance and biocontrol performance. PMID:26637302

  16. Stress tolerance and biocontrol performance of the yeast antagonist, Candida diversa, change with morphology transition.

    PubMed

    Li, Guangkun; Chi, Mengshan; Chen, Huizhen; Sui, Yuan; Li, Yan; Liu, Yongsheng; Zhang, Xiaojing; Sun, Zhiqiang; Liu, Guoqing; Wang, Qi; Liu, Jia

    2016-02-01

    As an eco-friendly management method, biological control of postharvest diseases, utilizing antagonistic yeasts, is a research topic receiving considerable attention. Detailed knowledge on the biology of yeast antagonists is crucial when considering their potential application and development as biocontrol products. Changes in the growth form, such as single-cell to pseudohyphae, have been associated with the mode of action in postharvest biocontrol yeasts. In this study, the antagonistic yeast, Candida diversa, reversibly shifted from a single-cell morphology on yeast peptone dextrose (YPD) medium with 2 % agar to a pseudohyphal morphology on YPD with 0.3 % agar. The tolerance of the pseudohyphal form to heat and oxidative stresses, as well as the biocontrol efficacy against Botrytis cinerea on apple and kiwifruit stored at 25 and 4 °C, was significantly higher as compared to the single-cell form. This study provides new information on the ability of C. diversa to change its morphology and the impact of the morphology shift on stress tolerance and biocontrol performance.

  17. [Construction of the flavinogenic yeast Candida famata strains with high riboflavin kinase activity using gene engineering].

    PubMed

    Ishchuk, O P; Iatsyshyn, V Iu; Dmytruk, K V; Voronovs'kyĭ, A Ia; Fedorovych, D V; Sybirnyĭ, A A

    2006-01-01

    The recombinant strains of the flavinogenic yeast Candida famata, which contain the DNA fragment consisting of the FMN1 gene (encoding the riboflavin kinase, enzyme that converts riboflavin to flavinmononucleotide) driven by the strong promoters (the regulated RIB1 or constitutive TEF1 promoter) were isolated. Riboflavin kinase activity in the isolated transformants was tested. The 6-8-fold increase of the riboflavin kinase activity was shown in the recombinant strains containing the integrated Debaryomyces hansenii FMN1 gene under the strong constitutive TEF1 promoter. The recombinant strains can be used for the following construction of flavinmononucleotide overproducers. PMID:17290783

  18. 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.

  19. On the reclassification of species assigned to Candida and other anamorphic ascomycetous yeast genera based on phylogenetic circumscription.

    PubMed

    Daniel, Heide-Marie; Lachance, Marc-André; Kurtzman, Cletus P

    2014-07-01

    Multigene phylogenies have been instrumental in revising the classification of ascosporic (teleomorph) yeasts in a natural system based on lines of descent. Although many taxonomic changes have already been implemented for teleomorph taxa, this is not yet the case for the large genus Candida and smaller anascosporic (anamorph) genera. In view of the recently introduced requirement that a fungal species or higher taxon be assigned only a single valid name under the new International Code of Nomenclature for algae, fungi, and plants (Melbourne Code), the current species of Candida and other anamorph yeast genera must undergo revision to make genus membership consistent with phylogenetic affinities. A review of existing data and analyses shows that certain Candida species may be assigned to teleomorph genera with high confidence using multigene phylogenies. Candida species that form well-circumscribed phylogenetic clades without any teleomorph member justify the creation of new genera. However, a considerable number of Candida species sit at the end of isolated and often long branches, and hence cannot be assigned to larger species groups. They should be maintained in Candida sensu lato until studied by multigene analyses in datasets with comprehensive taxon sampling. The principle of name stability has to be honoured to the largest extent compatible with a natural classification of Candida species. PMID:24748333

  20. [Cause of the appearance of cyanide-resistant respiration in the yeast Candida lipolytica].

    PubMed

    Akimenko, V K; Medentsev, A G

    1980-08-01

    Changes in the activity of the cell respiration of the yeast Candida lipolytica and its ATP, ADP, NADH, NAD+ pools during the development of the cyanide-resistant respiration were studied. A change-over of the yeast culture to the stationary growth phase conditioned by glucose exhaustion or aerobic incubation of the resting cells in the exponential growth phase without the exogenous carbon source were shown to be accompanied by: 1) decrease of the rate of oxygen consumption; 2) appearance of the cyanide-resistant respiration; 3) appearance of the benzhydroxamic acid-sensitive respiration; 4) appearance of stimulating dinitrophenol action on the rate of oxygen consumption; 5) increase in the ATP content and decrease of the ADP content in the cells. It was concluded that the appearance of the cyanide-resistant respiration is induced by the decrease of the activity of the respiratory chain due to the increase of the ATP concentration and the decrease of the ADP concentration in yeast cells. The functioning of the cyanide-resistant pathway of the electron transfer is one of the ways of NAD+ pool regulation in yeast cells.

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

    PubMed

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

    2016-08-01

    The yeast Candida utilis is used as a food additive and as a host for heterologous gene expression to produce various metabolites and proteins. Reliable protocols for intracellular production of recombinant proteins are available for C. utilis and have now been expanded to secrete proteins into the growth medium or to achieve surface display by linkage to a cell wall protein. A recombinant C. utilis strain was recently shown to induce oral tolerance in a mouse model of multiple sclerosis suggesting future applications in autoimmune therapy. Whole genome sequencing of C. utilis and its presumed parent Cyberlindnera (Pichia) jadinii demonstrated different ploidy but high sequence identity, consistent with identical recombinant technologies for both yeasts. C. jadinii was recently described as an antagonist to the important human fungal pathogen Candida albicans suggesting its use as a probiotic agent. The review summarizes the status of recombinant protein production in C. utilis, as well as current and future biotechnological and medical applications of C. utilis and C. jadinii. PMID:27357226

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

    PubMed

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

    2016-08-01

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

  3. Metabolic engineering and classic selection of the yeast Candida famata (Candida flareri) for construction of strains with enhanced riboflavin production.

    PubMed

    Dmytruk, Kostyantyn V; Yatsyshyn, Valentyna Y; Sybirna, Natalia O; Fedorovych, Daria V; Sibirny, Andriy A

    2011-01-01

    Currently, the mutant of the flavinogenic yeast Candida famata dep8 isolated by classic mutagenesis and selection is used for industrial riboflavin production. Here we report on construction of a riboflavin overproducing strain of C. famata using a combination of random mutagenesis based on the selection of mutants resistant to different antimetabolites as well as rational approaches of metabolic engineering. The conventional mutagenesis involved consecutive selection for resistance to riboflavin structural analog 7-methyl-8-trifluoromethyl-10-(1'-d-ribityl)isoalloxazine), 8-azaguanine, 6-azauracil, 2-diazo-5-oxo-L-norleucine and guanosine as well as screening for yellow colonies at high pH. The metabolic engineering approaches involved introduction of additional copies of transcription factor SEF1 and IMH3 (coding for IMP dehydrogenase) orthologs from Debaryomyces hansenii, and the homologous genes RIB1 and RIB7, encoding GTP cyclohydrolase II and riboflavin synthetase, the first and the last enzymes of riboflavin biosynthesis pathway, respectively. Overexpression of the aforementioned genes in riboflavin overproducer AF-4 obtained by classical selection resulted in a 4.1-fold increase in riboflavin production in shake-flask experiments. D. hansenii IMH3 and modified ARO4 genes conferring resistance to mycophenolic acid and fluorophenylalanine, respectively, were successfully used as new dominant selection markers for C. famata. PMID:21040798

  4. Isolation of the alkane inducible cytochrome P450 (P450alk) gene from the yeast Candida tropicalis

    EPA Science Inventory

    The gene for the alkane-inducible cytochrome P450, P450alk, has been isolated from the yeast Candida tropicalis by immunoscreening a λgt11 library. Isolation of the gene has been identified on the basis of its inducibility and partial DNA sequence. Transcripts of this gene were i...

  5. Structure and biological activities of beta-glucans from yeast and mycelial forms of Candida albicans.

    PubMed

    Miura, Noriko N; Adachi, Yoshiyuki; Yadomae, Toshiro; Tamura, Hiroshi; Tanaka, Shigenori; Ohno, Naohito

    2003-01-01

    We have achieved the extraction of cell wall beta-glucan from the mycelial form of Candida albicans (C. albicans) IFO 0579 (M-CSBG) by using acetic acid, sodium hypochlorite (NaClO), and dimethylsulfoxide (DMSO) treatments. The yield of M-CSBG was significantly lower (7.5% from dried mycelial cells) than that of the yeast form from C. albicans IFO 1385 (Y-CSBG, 25.9% from dried yeast cells). The properties of M-CSBG were similar to those of Y-CSBG in terms of nuclear magnetic resonance (NMR) spectra and limulus reactivity. Molecular weight (Mw) of M-CSBG was slightly higher than that of Y-CSBG. Both Y-CSBG and M-CSBG induced the production of comparable amounts of macrophage inflammatory protein-2 (MIP-2), a chemotactic factor, from mouse peritoneal exudate cells (PEC) in vitro. These findings suggest that the structure and properties of CSBG from yeast and mycelial cells are similar to each other. PMID:12725286

  6. Antimicrobial photodynamic therapy on Candida albicans pre-treated by fluconazole delayed yeast inactivation.

    PubMed

    Ferreira, Luis Rodolfo; Sousa, Aline Silva; Alvarenga, Letícia Heineck; Deana, Alessandro Melo; de Santi, Maria Eugênia Onofre Simões; Kato, Ilka Tiemy; Leal, Cintia Raquel Lima; Ribeiro, Martha Simões; Prates, Renato Araujo

    2016-09-01

    Antimicrobial photodynamic therapy (APDI) has been used to treat localized infection and the aim of this study was to evaluate the effect of APDI combined with fluconazole in suspension of Candida albicans. C. albicans ATCC90028 was subcultured onto Sabouraud agar and inocula were prepared at yeast density of 1×10(6)CFU/mL. Methylene blue (MB) was used with concentration of 100mM. Yeast cells were incubated for 30min in 24-well plate and then irradiated by LED (660nm; 690mW; A=2.7cm(2); I=250mW/cm(2)) with radiant exposure of 30, 60, and 120J/cm(2). The same APDI setup was used with 2h fluconazole (0.5μg/mL) incubation. A UV-vis optical absorption spectroscopy was achieved following fractionated irradiation up to 960s. There were substantial differences in the killing effect following MB-mediated APDI and C. albicans was eradicated in the both APDI groups. The fluconazole combined to APDI delayed the complete inactivation of the yeast (p<0.05). Spectroscopy showed a decrease in absorption following irradiation for all absorption peaks. APDI presented an antagonist effect in the presence of fluconazole. PMID:27179711

  7. [Cloning of structural genes involved in riboflavin synthesis of the yeast Candida famata].

    PubMed

    Dmytruk, K V; Abbas, C A; Voronovsky, A Y; Kshanovska, B V; Sybirna, K A; Sybirny, A A

    2004-01-01

    The riboflavin overproducing mutants of the flavinogenic yeast Candida famata isolated by conventional selection methods are used for the industrial production of vitamin B2. Recently, a transformation system was developed for C. famata using the leu2 mutant as a recipient strain and Saccharomyces cerevislae LEU2 gene as a selective marker. In this paper the cloning of C. famata genes for riboflavin synthesis on the basis of developed transformation system for this yeast species is described. Riboflavin autotrophic mutants were isolated from a previously selected C. famata leu2 strain. C. famata genomic DNA library was constructed and used for cloning of the corresponding structural genes for riboflavin synthesis by complementation of the growth defects on a medium without leucine and riboflavin. As a result, the DNA fragments harboring genes RIB1, RIB2, RIB5, RIB6 and RIB7 encoding GTP cyclohydrolase, reductase, dimethylribityllumazine synthase, dihydroxybutanone phosphate synthase and riboflavin synthase, were isolated and subsequently subcloned to the smallest possible fragments. The plasmids with these genes successfully complemented riboflavin auxotrophies of the corresponding mutants of another flavinogenic yeast Pichia guilliermondii. This suggested that C. famata structural genes for riboflavin synthesis and not some of the supressor genes were cloned. PMID:15909421

  8. Efficacy of zosteric acid sodium salt on the yeast biofilm model Candida albicans.

    PubMed

    Villa, Federica; Pitts, Betsey; Stewart, Philip S; Giussani, Barbara; Roncoroni, Simone; Albanese, Domenico; Giordano, Carmen; Tunesi, Marta; Cappitelli, Francesca

    2011-10-01

    Candida albicans is the most notorious and the most widely studied yeast biofilm former. Design of experiments (DoE) showed that 10 mg/L zosteric acid sodium salt reduced C. albicans adhesion and the subsequent biofilm formation by at least 70%, on both hydrophilic and hydrophobic surfaces of 96-well plates. Indeed, biofilm imaging revealed the dramatic impact of zosteric acid sodium salt on biofilm thickness and morphology, due to the inability of the cells to form filamentous structures while remaining metabolically active. In the same way, 10 mg/L zosteric acid sodium salt inhibited C. albicans biofilm formation when added after the adhesion phase. Contrary to zosteric acid sodium salt, methyl zosterate did not affect yeast biofilm. In addition, zosteric acid sodium salt enhanced sensitivity to chlorhexidine, chlorine, hydrogen peroxide, and cis-2-decenoic acid, with a reduction of 0.5 to 8 log units. Preliminary in vitro studies using suitable primary cell based models revealed that zosteric acid sodium salt did not compromise the cellular activity, adhesion, proliferation or morphology of either the murine fibroblast line L929 or the human osteosarcoma line MG-63. Thus the use of zosteric acid sodium salt could provide a suitable, innovative, preventive, and integrative approach to preventing yeast biofilm formation. PMID:21614460

  9. Pretreatment of the yeast antagonist, Candida oleophila, with glycine betaine increases oxidative stress tolerance in the microenvironment of apple wounds.

    PubMed

    Sui, Yuan; Liu, Jia; Wisniewski, Michael; Droby, Samir; Norelli, John; Hershkovitz, Vera

    2012-06-15

    In response to wounding, harvested fruit tissues of apple and citrus exhibit the production of reactive oxygen species (ROS). ROS production is greater when yeast antagonists used as biocontrol agents are applied in the wounds. These phenomena result in an oxidative stress environment for the yeast antagonists. It has been demonstrated that pre-exposure of some of these yeast antagonists to sublethal abiotic stress (heat or hydrogen peroxide), or stress-ameliorating compounds such as glycine betaine (GB) can induce subsequent oxidative stress tolerance in the antagonistic yeast. The increased level of oxidative stress tolerance has been demonstrated in vitro and is characterized by higher levels of antioxidant gene expression, increased production of trehalose, and lower levels of ROS when yeast are exposed to a subsequent oxidative stress. The current study determined whether or not the effects of GB on yeast antagonists determined in vitro persist and are present in planta when yeast are applied to wounded apples. The effect of exogenous GB on the production of ROS in the yeast antagonist, Candida oleophila, was determined after the yeast was placed in apple wounds. Oxidative damage to yeast cells recovered from apple wounds was also monitored. Results indicated that GB treatment improved the adaptation of C. oleophila to apple fruit wounds. Compared to untreated control yeast cells, GB-treated cells recovered from the oxidative stress environment of apple wounds exhibited less accumulation of ROS and lower levels of oxidative damage to cellular proteins and lipids. Additionally, GB-treated yeast exhibited greater biocontrol activity against Penicillium expansum and Botrytis cinerea, and faster growth in wounds of apple fruits compared to untreated yeast. The expression of major antioxidant genes, including peroxisomal catalase, peroxiredoxin TSA1, and glutathione peroxidase was elevated in the yeast by GB treatment. This study supports the premise that

  10. Cloning of the transketolase gene from erythritol-producing yeast Candida magnoliae.

    PubMed

    Yoo, Boung-Hyuk; Park, Eun-Hee; Seo, Jin-Ho; Kim, Myoung-Dong

    2014-10-01

    The entire nucleotide sequence of the TKL1 gene encoding transketolase (TKL) in an erythritolproducing yeast of Candida magnoliae was determined by degenerate polymerase chain reaction and genome walking. Sequence analysis revealed an open reading frame of C. magnoliae TKL1 (CmTKL1) that spans 2,088 bp and encodes 696 amino acids, sharing 61.7% amino acid identity to Kluyveromyces lactis TKL. Functional analysis showed that CmTKL1 complemented a Saccharomyces cerevisiae tkl1 tkl2 double mutant for growth in the absence of aromatic amino acids and restored transketolase activity in this mutant. An enzyme activity assay and RT-PCR revealed that the expression of CmTKL1 is induced by fructose, H2O2, and KCl. The GenBank accession number for C. magnoliae TKL1 is KF751756.

  11. Nanoscale effects of caspofungin against two yeast species, Saccharomyces cerevisiae and Candida albicans.

    PubMed

    Formosa, C; Schiavone, M; Martin-Yken, H; François, J M; Duval, R E; Dague, E

    2013-08-01

    Saccharomyces cerevisiae and Candida albicans are model yeasts for biotechnology and human health, respectively. We used atomic force microscopy (AFM) to explore the effects of caspofungin, an antifungal drug used in hospitals, on these two species. Our nanoscale investigation revealed similar, but also different, behaviors of the two yeasts in response to treatment with the drug. While administration of caspofungin induced deep cell wall remodeling in both yeast species, as evidenced by a dramatic increase in chitin and decrease in β-glucan content, changes in cell wall composition were more pronounced with C. albicans cells. Notably, the increase of chitin was proportional to the increase in the caspofungin dose. In addition, the Young modulus of the cell was three times lower for C. albicans cells than for S. cerevisiae cells and increased proportionally with the increase of chitin, suggesting differences in the molecular organization of the cell wall between the two yeast species. Also, at a low dose of caspofungin (i.e., 0.5× MIC), the cell surface of C. albicans exhibited a morphology that was reminiscent of cells expressing adhesion proteins. Interestingly, this morphology was lost at high doses of the drug (i.e., 4× MIC). However, the treatment of S. cerevisiae cells with high doses of caspofungin resulted in impairment of cytokinesis. Altogether, the use of AFM for investigating the effects of antifungal drugs is relevant in nanomedicine, as it should help in understanding their mechanisms of action on fungal cells, as well as unraveling unexpected effects on cell division and fungal adhesion.

  12. Genome engineering in the yeast pathogen Candida glabrata using the CRISPR-Cas9 system

    PubMed Central

    Enkler, Ludovic; Richer, Delphine; Marchand, Anthony L.; Ferrandon, Dominique; Jossinet, Fabrice

    2016-01-01

    Among Candida species, the opportunistic fungal pathogen Candida glabrata has become the second most common causative agent of candidiasis in the world and a major public health concern. Yet, few molecular tools and resources are available to explore the biology of C. glabrata and to better understand its virulence during infection. In this study, we describe a robust experimental strategy to generate loss-of-function mutants in C. glabrata. The procedure is based on the development of three main tools: (i) a recombinant strain of C. glabrata constitutively expressing the CRISPR-Cas9 system, (ii) an online program facilitating the selection of the most efficient guide RNAs for a given C. glabrata gene, and (iii) the identification of mutant strains by the Surveyor technique and sequencing. As a proof-of-concept, we have tested the virulence of some mutants in vivo in a Drosophila melanogaster infection model. Our results suggest that yps11 and a previously uncharacterized serine/threonine kinase are involved, directly or indirectly, in the ability of the pathogenic yeast to infect this model host organism. PMID:27767081

  13. Trophic effect of a methanol yeast extract on 3T3 fibroblast cells.

    PubMed

    Gallo, Dominique; Dillemans, Monique; Allardin, David; Priem, Fabian; Van Nedervelde, Laurence

    2014-01-01

    With regard to the increase of human life expectancy, interest for topical treatments aimed to counteract skin aging is still growing. Hence, research for bioactive compounds able to stimulate skin fibroblast activity is an attractive topic. Having previously described the effects of a new methanol yeast extract on growth and metabolic activity of Saccharomyces cerevisiae, we studied its effects on 3T3 fibroblasts to evaluate its potential antiaging property. This investigation demonstrates that this extract increases proliferation as well as migration of 3T3 cells and decreases their entrance in senescence and apoptosis phases. Altogether, these results open new perspectives for the formulation of innovative antiaging topical treatments.

  14. A Comparison of Two Yeast MnSODs: Mitochondrial Saccharomyces cerevisiae versus Cytosolic Candida albicans

    PubMed Central

    Sheng, Yuewei; Stich, Troy A.; Barnese, Kevin; Gralla, Edith B.; Cascio, Duilio; Britt, R. David; Cabelli, Diane E.; Valentine, Joan Selverstone

    2011-01-01

    Human MnSOD is significantly more product-inhibited than bacterial MnSODs at high concentrations of superoxide (O2−). This behavior limits the amount of H2O2 produced at high [O2−]; its desirability can be explained by the multiple roles of H2O2 in mammalian cells, particularly its role in signaling. To investigate the mechanism of product inhibition in MnSOD, two yeast MnSODs, one from Saccharomyces cerevisiae mitochondria (ScMnSOD) and the other from Candida albicans cytosol (CaMnSODc), were isolated and characterized. ScMnSOD and CaMnSODc are similar in catalytic kinetics, spectroscopy and redox chemistry, and they both rest predominantly in the reduced state (unlike most other MnSODs). At high [O2−] the dismutation efficiencies of the yeast MnSODs surpass those of human and bacterial MnSODs, due to very low level of product inhibition. Optical and parallel-mode electron paramagnetic resonance (EPR) spectra suggest the presence of two Mn3+ species in yeast Mn3+SODs, including the well-characterized 5-coordinate Mn3+ species and a 6-coordinate L-Mn3+ species with hydroxide as the putative sixth ligand (L). The first and second coordination spheres of ScMnSOD are more similar to bacterial than to human MnSOD. Gln154, an H-bond donor to the Mn-coordinated solvent molecule, is slightly further away from Mn in yeast MnSODs, which may result in their unusual resting state. Mechanistically, the high efficiency of yeast MnSODs could be ascribed to putative translocation of an outer-sphere solvent molecule, which could destabilize the inhibited complex and enhance proton transfer from protein to peroxide. Our studies on yeast MnSODs indicate the unique nature of human MnSOD in that it predominantly undergoes the inhibited pathway at high [O2−]. PMID:22077216

  15. A Comparison of Two Yeast MnSODs: Mitochondrial Saccharomyces cerevisiae versus Cytosolic Candida albicans

    SciTech Connect

    Sheng Y.; Cabelli D.; Stich, T.A.; Barnese, K.; Gralla, E.B.; Cascio, D.; Britt, R.D.; Valentine, J.S.

    2011-12-28

    Human MnSOD is significantly more product-inhibited than bacterial MnSODs at high concentrations of superoxide (O{sub 2}{sup -}). This behavior limits the amount of H{sub 2}O{sub 2} produced at high [O{sub 2}{sup -}]; its desirability can be explained by the multiple roles of H{sub 2}O{sub 2} in mammalian cells, particularly its role in signaling. To investigate the mechanism of product inhibition in MnSOD, two yeast MnSODs, one from Saccharomyces cerevisiae mitochondria (ScMnSOD) and the other from Candida albicans cytosol (CaMnSODc), were isolated and characterized. ScMnSOD and CaMnSODc are similar in catalytic kinetics, spectroscopy, and redox chemistry, and they both rest predominantly in the reduced state (unlike most other MnSODs). At high [O{sub 2}{sup -}], the dismutation efficiencies of the yeast MnSODs surpass those of human and bacterial MnSODs, due to very low level of product inhibition. Optical and parallel-mode electron paramagnetic resonance (EPR) spectra suggest the presence of two Mn{sup 3+} species in yeast Mn{sup 3+}SODs, including the well-characterized 5-coordinate Mn{sup 3+} species and a 6-coordinate L-Mn{sup 3+} species with hydroxide as the putative sixth ligand (L). The first and second coordination spheres of ScMnSOD are more similar to bacterial than to human MnSOD. Gln154, an H-bond donor to the Mn-coordinated solvent molecule, is slightly further away from Mn in yeast MnSODs, which may result in their unusual resting state. Mechanistically, the high efficiency of yeast MnSODs could be ascribed to putative translocation of an outer-sphere solvent molecule, which could destabilize the inhibited complex and enhance proton transfer from protein to peroxide. Our studies on yeast MnSODs indicate the unique nature of human MnSOD in that it predominantly undergoes the inhibited pathway at high [O{sub 2}{sup -}].

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

    PubMed Central

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

    2013-01-01

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

  17. Antimicrobial potential of some plant extracts against Candida species.

    PubMed

    Höfling, J F; Anibal, P C; Obando-Pereda, G A; Peixoto, I A T; Furletti, V F; Foglio, M A; Gonçalves, R B

    2010-11-01

    The increase in the resistance to antimicrobial drugs in use has attracted the attention of the scientific community, and medicinal plants have been extensively studied as alternative agents for the prevention of infections. The Candida genus yeast can become an opportunistic pathogen causing disease in immunosuppressive hosts. The purpose of this study was to evaluate dichloromethane and methanol extracts from Mentha piperita, Rosmarinus officinalis, Arrabidaea chica, Tabebuia avellanedae, Punica granatum and Syzygium cumini against Candida species through the analysis of Minimum Inhibitory Concentration (MIC). Results presented activity of these extracts against Candida species, especially the methanol extract. PMID:21180915

  18. Isolation and chemical characterization of plasma membranes from the yeast and mycelial forms of Candida albicans.

    PubMed

    Marriott, M S

    1975-01-01

    It has been possible to induce the yeast-mycelium transformation in Candida albicans by growth of the organism under completely defined conditions in batch culture. Protoplasts have been obtained from the two forms by using a lytic enzyme preparation from Streptomyces violaceus. A plasma membrane fraction was prepared by osmotic lysis of these protoplasts and fractionated by using a combination of differential and discontinuous sucrose density-gradient flotation centrifugation. The purity of this fraction was determined by radioactive dansylation and iodination of plasma membranes of intact protoplasts followed by localization of the radioactivity upon fractionation. This procedure demonstrated less than 4% contamination of the plasma membrane fraction with other cell membranes. Chemical analysis of this fraction revealed that the major components were protein and lipid. Membranes from the yeast form contained (w/w): 50% protein, 45% lipid, 9% carbohydrate and 0.3% nucleic acid. Plasma membranes from the mycelial form contained significantly more carbohydrate and were found to be composed of (w/w): 43% protein, 31% lipid, 25% carbohydrate and 0.5% nucleic acid. Marked differences were also observed between the phospholipid, free and esterified sterols, and total fatty acids of membranes from the two forms of the organism. PMID:1089750

  19. Characterization of cellobiose fermentations to ethanol by yeasts. [Candida lusitaniae and C. wickerhamii

    SciTech Connect

    Freer, S.N.; Detroy, R.W.

    1983-02-01

    Twenty-two different yeasts were screened for their ability to ferment both glucose and cellobiose. The fermentation characteristics of Candida lusitaniae (NRRL Y-5394) and C. wickerhamii (NRRL Y-2563) were selected for further study because their initial rate of ethanol production from cellobiose was faster than the other test culture. C. lusitaniae produced 44 g/L ethanol from 90 g/L cellobiose after 5-7 days. When carbohydrate concentrations were employed, fermentation ceased when the ethanol concentration reached 45-60 g/L. C. lusitaniae exhibited barely detectable levels of beta-glucosidase, even though the culture actively fermented cellobiose. C. wickerhamii produced ethanol from cellobiose at a rate equivalent to C. lusitaniae; however, once the ethanol concentration reached 20 g/L, fermentation ceased. Using p-nitrophenyl-beta-D-glucopyranoside (pNPG) as substrate, beta- glucosidase (3-5 U/mL) was detected when C. wickerhamii was grown anaerobically on glucose or cellobiose. About 35% of the beta-glucosidase activity was excreted into the medium. The cell-associated activity was highest against pNPG and salicin. Approximately 100-fold less activity was detected with cellobiose as substrate. When employing these organisms in a simultaneous saccharification-fermentation of Avicel, using Trichoderma reesei cellulase as the saccharifying agent 10-30% more ethanol was produced by the two yeasts capable of fermenting cellobiose than by the control, Saccharomyces cerevisiae. (Refs. 27).

  20. Development of a transformation system for the flavinogenic yeast Candida famata.

    PubMed

    Voronovsky, Andriy A; Abbas, Charles A; Fayura, Lyubov R; Kshanovska, Barbara V; Dmytruk, Kostyantyn V; Sybirna, Kateryna A; Sibirny, Andriy A

    2002-08-01

    Riboflavin-overproducing mutants of the flavinogenic yeast Candida famata are used for industrial riboflavin production. This paper describes the development of an efficient transformation system for this species. Leucine-deficient mutants have been isolated from C. famata VKM Y-9 wild-type strain. Among them leu2 mutants were identified by transformation to leucine prototrophy with plasmids YEp13 and PRpL2 carrying the Saccharomyces cerevisiae LEU2 gene. DNA fragments (called CfARSs) conferring increased transformation frequencies and extrachromosomal replication were isolated from a C. famata gene library constructed on the integrative vector containing the S. cerevisiae LEU2 gene as a selective marker. The smallest cloned fragment (CfARS16) has been sequenced. This one had high adenine plus thymine (A+T) base pair content and a sequence homologous to the S. cerevisiae ARS Consensus Sequence. Methods for spheroplast transformation and electrotransformation of the yeast C. famata were optimized. They conferred high transformation frequencies (up to 10(5) transformants per microg DNA) with a C. famata leu2 mutant using replicative plasmids containing the S. cerevisiae LEU2 gene as a selective marker. Riboflavin-deficient mutants were isolated from the C. famata leu2 strain and their biochemical identification was carried out. Using the developed transformation system, several C. famata genomic fragments complementing mutations of structural genes for riboflavin biosynthesis (coding for GTP cyclohydrolase, reductase, dihydroxybutanone phosphate synthase and riboflavin synthase, respectively) have been cloned. PMID:12702288

  1. Insertion mutagenesis of the yeast Candida famata (Debaryomyces hansenii) by random integration of linear DNA fragments.

    PubMed

    Dmytruk, Kostyantyn V; Voronovsky, Andriy Y; Sibirny, Andriy A

    2006-09-01

    The feasibility of using random insertional mutagenesis to isolate mutants of the flavinogenic yeast Candida famata was explored. Mutagenesis was performed by transformation of the yeast with an integrative plasmid containing the Saccharomyces cerevisiae LEU2 gene as a selective marker. The addition of restriction enzyme together with the plasmid (restriction enzyme-mediated integration, REMI) increased the transformation frequency only slightly. Integration of the linearized plasmid occurred randomly in the C. famata genome. To investigate the potential of insertional mutagenesis, it was used for tagging genes involved in positive regulation of riboflavin synthesis in C. famata. Partial DNA sequencing of tagged genes showed that they were homologous to the S. cerevisiae genes RIB1, MET2, and SEF1. Intact orthologs of these genes isolated from Debaryomyces hansenii restored the wild phenotype of the corresponding mutants, i.e., the ability to overproduce riboflavin under iron limitation. The Staphylococcus aureus ble gene conferring resistance to phleomycin was used successfully in the study as a dominant selection marker for C. famata. The results obtained indicate that insertional mutagenesis is a powerful tool for tagging genes in C. famata. PMID:16770625

  2. Insertion mutagenesis of the yeast Candida famata (Debaryomyces hansenii) by random integration of linear DNA fragments.

    PubMed

    Dmytruk, Kostyantyn V; Voronovsky, Andriy Y; Sibirny, Andriy A

    2006-09-01

    The feasibility of using random insertional mutagenesis to isolate mutants of the flavinogenic yeast Candida famata was explored. Mutagenesis was performed by transformation of the yeast with an integrative plasmid containing the Saccharomyces cerevisiae LEU2 gene as a selective marker. The addition of restriction enzyme together with the plasmid (restriction enzyme-mediated integration, REMI) increased the transformation frequency only slightly. Integration of the linearized plasmid occurred randomly in the C. famata genome. To investigate the potential of insertional mutagenesis, it was used for tagging genes involved in positive regulation of riboflavin synthesis in C. famata. Partial DNA sequencing of tagged genes showed that they were homologous to the S. cerevisiae genes RIB1, MET2, and SEF1. Intact orthologs of these genes isolated from Debaryomyces hansenii restored the wild phenotype of the corresponding mutants, i.e., the ability to overproduce riboflavin under iron limitation. The Staphylococcus aureus ble gene conferring resistance to phleomycin was used successfully in the study as a dominant selection marker for C. famata. The results obtained indicate that insertional mutagenesis is a powerful tool for tagging genes in C. famata.

  3. The yeast Starmerella bacillaris (synonym Candida zemplinina) shows high genetic diversity in winemaking environments.

    PubMed

    Masneuf-Pomarede, Isabelle; Juquin, Elodie; Miot-Sertier, Cécile; Renault, Philippe; Laizet, Yec'han; Salin, Franck; Alexandre, Hervé; Capozzi, Vittorio; Cocolin, Luca; Colonna-Ceccaldi, Benoit; Englezos, Vasileios; Girard, Patrick; Gonzalez, Beatriz; Lucas, Patrick; Mas, Albert; Nisiotou, Aspasia; Sipiczki, Matthias; Spano, Giuseppe; Tassou, Chrysoula; Bely, Marina; Albertin, Warren

    2015-08-01

    The yeast Candida zemplinina (Starmerella bacillaris) is frequently isolated from grape and wine environments. Its enological use in mixed fermentation with Saccharomyces cerevisiae has been extensively investigated these last few years, and several interesting features including low ethanol production, fructophily, glycerol and other metabolites production, have been described. In addition, molecular tools allowing the characterization of yeast populations have been developed, both at the inter- and intraspecific levels. However, most of these fingerprinting methods are not compatible with population genetics or ecological studies. In this work, we developed 10 microsatellite markers for the C. zemplinina species that were used for the genotyping of 163 strains from nature or various enological regions (28 vineyards/wineries from seven countries). We show that the genetic diversity of C. zemplinina is shaped by geographical localization. Populations isolated from winemaking environments are quite diverse at the genetic level: neither clonal-like behaviour nor specific genetic signature were associated with the different vineyards/wineries. Altogether, these results suggest that C. zemplinina is not under selective pressure in winemaking environments. PMID:26071435

  4. Candida riodocensis and Candida cellae, two new yeast species from the Starmerella clade associated with solitary bees in the Atlantic rain forest of Brazil.

    PubMed

    Pimentel, Mariana R C; Antonini, Yasmine; Martins, Rogério P; Lachance, Marc-André; Rosa, Carlos A

    2005-06-01

    Two new ascomycetous yeast species belonging to the Starmerella clade were discovered in nests of two solitary bee species in the Atlantic rain forest of Brazil. Candida riodocensis was isolated from pollen-nectar provisions, larvae and fecal pellets of nests of Megachile sp., and Candida cellae was found in pollen-nectar provisions of Centris tarsata. Analysis of the sequences of the D1/D2 large-subunit ribosomal DNA showed that C. riodocensis is phylogenetically related to C. batistae, and the closest relative of C. cellae is C. etchellsii. The type strains are C. riodocensis UFMG-MG02 (=CBS 10087(T) = NRRL Y-27859(T)) and C. cellae UFMG-PC04 (=CBS 10086(T) = NRRL Y-27860(T)). PMID:15925316

  5. Wickerhamiella pagnoccae sp. nov. and Candida tocantinsensis sp. nov., two ascomycetous yeasts from flower bracts of Heliconia psittacorum (Heliconiaceae).

    PubMed

    Barbosa, Anne C; Morais, Camila G; Morais, Paula B; Rosa, Luiz H; Pimenta, Raphael S; Lachance, Marc-André; Rosa, Carlos A

    2012-02-01

    Two novel yeast species were isolated from nectar of flower bracts of Heliconia psittacorum (Heliconiaceae) collected in a Cerrado ecosystem in the state of Tocantins, northern Brazil. Wickerhamiella pagnoccae sp. nov., which is closely related to Candida jalapaonensis, is heterothallic and produces one spheroid ascospore per ascus. Candida tocantinsensis sp. nov. belongs to the Metschnikowiaceae clade and its nearest relative is Candida ubatubensis, but the sequence identity (%) in the D1/D2 domains of the rRNA gene is low. The type strain of W. pagnoccae is UFMG-F18C1(T) ( = CBS 12178(T) = NRRL Y-48735(T)) and the type strain of C. tocantinsensis is UFMG-F16D1(T) ( = CBS 12177(T) = NRRL Y-48734(T)).

  6. [The cloning and expression of the gene for beta-galactosidase from Candida pseudotropicalis yeasts in Saccharomyces cerevisiae cells].

    PubMed

    Tretiak, K A; Zakal'skiĭ, A E; Gudz', S P

    1998-01-01

    The gene of beta-galactosidase of lactose-assimilating yeast Candida pseudotropicalis was cloned in pG2 and pBG2-3 hybrid shuttle vectors and expressed in Saccharomyces cerevisiae laboratory strains under the control of own promoter. The plasmids were able to replicate autonomously with relative stability in transformants of baker's yeasts. The availability of glucose or lactose in the medium influenced the recombinant plasmid stability and the expression of the cloned gene. A number of experiments have shown that the LAC+ phenotype in pG2-transformed Saccharomyces cerevisiae was due to the expression of the Candida pseudotropicalis lactose permease gene that is probably located in SaIG1/XhoI DNA fragment about 4.3 kb long. Southern hybridization experiments showed that LAC(+)-transformants of Saccharomyces cerevisiae contained both autonomously-replicative, and integrative pG2 plasmid.

  7. Spectrophotometric evaluation of selenium binding by Saccharomyces cerevisiae ATCC MYA-2200 and Candida utilis ATCC 9950 yeast.

    PubMed

    Kieliszek, Marek; Błażejak, Stanisław; Płaczek, Maciej

    2016-05-01

    In this study, the ability of selenium binding the biomas of Saccharomyces cerevisiae ATCC MYA-2200 and Candida utilis ATCC 9950 was investigated. Sodium selenite(IV) salts were added to the experimental media at concentrations of 10, 20, 40, and 60 mg Se(4+) L(-1). In the tested concentration range, one concentration reported a significant reduction in the biomass yield of both yeast strains. Intense growth was observed for C. utilis yeast, which reached the highest biomass yield of 15 gd.w.L(-1) after 24h cultivation in the presence of 10mg Se(4+) L(-1). Based on the use of spectrophotometric method for the determination of selenium content by using Variamine Blue as a chromogenic agent, efficient accumulation of this element in the biomass of the investigated yeast was observed. The highest amount of selenium, that is, 5.64 mg Se(4+)gd.w.(-1), was bound from the environment by S. cerevisiae ATCC MYA-2200 cultured in the presence of 60 mg Se(4+) L(-1) medium 72h Slightly less amount, 5.47 mg Se(4+) gd.w.(-1), was absorbed by C. utilis ATCC 9950 during similar cultural conditions. Based on the results of the biomass yield and the use of selenium from the medium, it can be observed that yeasts of the genus Candida are more efficient in binding this element, and this property finds practical application in the production of selenium-enriched yeast.

  8. Spectrophotometric evaluation of selenium binding by Saccharomyces cerevisiae ATCC MYA-2200 and Candida utilis ATCC 9950 yeast.

    PubMed

    Kieliszek, Marek; Błażejak, Stanisław; Płaczek, Maciej

    2016-05-01

    In this study, the ability of selenium binding the biomas of Saccharomyces cerevisiae ATCC MYA-2200 and Candida utilis ATCC 9950 was investigated. Sodium selenite(IV) salts were added to the experimental media at concentrations of 10, 20, 40, and 60 mg Se(4+) L(-1). In the tested concentration range, one concentration reported a significant reduction in the biomass yield of both yeast strains. Intense growth was observed for C. utilis yeast, which reached the highest biomass yield of 15 gd.w.L(-1) after 24h cultivation in the presence of 10mg Se(4+) L(-1). Based on the use of spectrophotometric method for the determination of selenium content by using Variamine Blue as a chromogenic agent, efficient accumulation of this element in the biomass of the investigated yeast was observed. The highest amount of selenium, that is, 5.64 mg Se(4+)gd.w.(-1), was bound from the environment by S. cerevisiae ATCC MYA-2200 cultured in the presence of 60 mg Se(4+) L(-1) medium 72h Slightly less amount, 5.47 mg Se(4+) gd.w.(-1), was absorbed by C. utilis ATCC 9950 during similar cultural conditions. Based on the results of the biomass yield and the use of selenium from the medium, it can be observed that yeasts of the genus Candida are more efficient in binding this element, and this property finds practical application in the production of selenium-enriched yeast. PMID:27049131

  9. The Evaluation of the Distribution of Yeast like Fungi 'Candida Species' at a Tertiary Care Center in Western Turkey

    PubMed Central

    Ece, Gulfem; Samlioglu, Pinar; Akkoclu, Gulgun; Atalay, Sabri; Kose, Sukran

    2012-01-01

    Objective: Candida infections have increased due to transplant patients, prolonged ICU stay and invasive procedures. The most common isolated strain is C. albicans. The aim of this study was to evaluate the distribution of Candida isolates at Tepecik Education and Research Hospital. Materials and Methods: Yeast like fungi were isolated between 13.01.2010 and 19.08.2011 at Mycology Laboratory. The identification was done by conventional methods and carbohydrate assimilation profile using the ID32C identification system (Biomerieux, France). Results: Yeast like fungi were isolated from 337 clinical specimens. They consisted of urine, blood culture, respiratory specimen and wound. The most isolated yeast strains were C.albicans (38.6%), C.tropicalis (13.9%), C. parapsilosis (28.4%), C.glabrata (7.4%), C.krusei (3.8%). Conclusion: Recently there is an increment in Candida infections. In this study the most common strain was C.albicans and the rate C. glabrata and C. krusei isolates were lower than expected. C. parapsilosis was the most isolated strain in blood cultures and this may be due to invasive procedures and the use of indwelling catheters. PMID:23028245

  10. Candida auris sp. nov., a novel ascomycetous yeast isolated from the external ear canal of an inpatient in a Japanese hospital.

    PubMed

    Satoh, Kazuo; Makimura, Koichi; Hasumi, Yayoi; Nishiyama, Yayoi; Uchida, Katsuhisa; Yamaguchi, Hideyo

    2009-01-01

    A single strain of a novel ascomycetous yeast species belonging to the genus Candida was isolated from the external ear canal of an inpatient in a Japanese hospital. Analyses of the 26S rDNA D1/D2 domain, nuclear ribosomal DNA ITS region sequences, and chemotaxonomic studies indicated that this strain represents a new species with a close phylogenetic relationship to Candida ruelliae and Candida haemulonii in the Metschnikowiaceae clade. This strain grew well at 40 degrees C, but showed slow and weak growth at 42 degrees C. The taxonomic description of Candida auris sp. nov. is proposed (type strain JCM15448T= CBS10913T= DSM21092T).

  11. Isolation and characterization of Candida membranifaciens subsp. flavinogenie W14-3, a novel riboflavin-producing marine yeast.

    PubMed

    Wang, Lin; Chi, Zhenmin; Wang, Xianghong; Ju, Liang; Chi, Zhe; Guo, Ning

    2008-01-01

    We found that the marine yeast strain W14-3 isolated from seawater of China Eastern Sea could produce riboflavin. It is interesting to observe that the marine yeast strain produced a large amount of riboflavin in the medium containing xylose, sucrose, galactose and maltose under the conditions of vigorous shaking. The yeast strain was found to belong to Candida membranifaciens subsp. flavinogenie based on the results of routine and molecular identification. The protein sequences deduced from the partial genes encoding GTP cyclohydrolase II and 3,4-dihydroxy-2-butanone-4-phosphate synthase in the yeast exhibited high identity with those of the corresponding enzymes for riboflavin biosynthesis in other yeasts. Fe(3+) available in the medium repressed riboflavin production and expression of the genes responsible for riboflavin biosynthesis in the yeast. The results have evidenced that a riboflavin synthesis pathway indeed existed in the yeast. This is the first study to report that C. membranifaciens subsp. flavinogenie W14-3 from the marine environment could produce riboflavin. PMID:18262398

  12. Metabolic and bioprocess engineering of the yeast Candida famata for FAD production.

    PubMed

    Yatsyshyn, Valentyna Y; Fedorovych, Dariya V; Sibirny, Andriy A

    2014-05-01

    Flavins in the form of flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD) play an important role in metabolism as cofactors for oxidoreductases and other enzymes. Flavin nucleotides have applications in the food industry and medicine; FAD supplements have been efficiently used for treatment of some inheritable diseases. FAD is produced biotechnologically; however, this compound is much more expensive than riboflavin. Flavinogenic yeast Candida famata synthesizes FAD from FMN and ATP in the reaction catalyzed by FAD synthetase, a product of the FAD1 gene. Expression of FAD1 from the strong constitutive promoter TEF1 resulted in 7- to 15-fold increase in FAD synthetase activity, FAD overproduction, and secretion to the culture medium. The effectiveness of FAD production under different growth conditions by one of these recombinant strains, C. famata T-FD-FM 27, was evaluated. First, the two-level Plackett-Burman design was performed to screen medium components that significantly influence FAD production. Second, central composite design was adopted to investigate the optimum value of the selected factors for achieving maximum FAD yield. FAD production varied most significantly in response to concentrations of adenine, KH2PO4, glycine, and (NH4)2SO4. Implementation of these optimization strategies resulted in 65-fold increase in FAD production when compared to the non-optimized control conditions. Recombinant strain that has been cultivated for 40 h under optimized conditions achieved a FAD accumulation of 451 mg/l. So, for the first time yeast strains overproducing FAD were obtained, and the growth media composition for maximum production of this nucleotide was designed. PMID:24595668

  13. New anamorphic yeast species: Candida infanticola sp. nov., Candida polysorbophila sp. nov., Candida transvaalensis sp. nov. and Trigonopsis californica sp. nov.

    PubMed

    Kurtzman, Cletus P

    2007-08-01

    Three new species of Candida and a new species of Trigonopsis are described based on their recognition from phylogenetic analysis of gene sequences from large subunit ribosomal RNA, ITS1/ITS2 rRNA, mitochondrial small subunit rRNA and cytochrome oxidase II. Candida infanticola sp. nov. (type strain NRRL Y-17858, CBS 7922) was isolated from the ear of an infant in Germany and is closely related to Candida sorbophila. Candida polysorbophila sp. nov. (type strain NRRL Y-27161, CBS 7317) is a member of the Zygoascus clade and was isolated in South Africa as a contaminant from an emulsion of white oil and polysorbate. Candida transvaalensis sp. nov. (type strain NRRL Y-27140, CBS 6663) was obtained from forest litter, the Transvaal, South Africa, and forms an isolated clade with Candida santjacobensis. Trigonopsis californica sp. nov. (type strain NRRL Y-27307, CBS 10351) represents a contaminant from wine in California, and forms a well-supported clade with Trigonopsis cantarellii, Trigonopsis variabilis and Trigonopsis vinaria.

  14. Dual crosslinked iminoboronate-chitosan hydrogels with strong antifungal activity against Candida planktonic yeasts and biofilms.

    PubMed

    Ailincai, Daniela; Marin, Luminita; Morariu, Simona; Mares, Mihai; Bostanaru, Andra-Cristina; Pinteala, Mariana; Simionescu, Bogdan C; Barboiu, Mihai

    2016-11-01

    Chitosan based hydrogels are a class of cross-linked materials intensely studied for their biomedical, industrial and environmental application, but their biomedical use is limited because of the toxicity of different organic crosslinkers. To overcome this disadvantage, a new strategy to produce supramolecular chitosan hydrogels using low molecular weight compounds able to form covalent linkages and H-bonds to give a dual crosslinking is proposed. For this purpose we used 2-formylphenylboronic acid, which brings the advantage of imine stabilization via iminoboronate formation and potential antifungal activity due to the presence of boric acid residue. FTIR and NMR spectroscopy indicated that the gelling process took place by chemo-physical crosslinking forming a dual iminoboronate-chitosan network. Further, X-ray diffraction demonstrated a three-dimensional nanostructuring of the iminoboronate network with consequences on the micrometer-scale morphology and on the improvement of mechanical properties, as demonstrated by SEM and rheological investigation. The hydrogels proved strong antifungal activity against Candida planktonic yeasts and biofilms, promising to be a friendly treatment of the recurrent vulvovaginitis infections. PMID:27516277

  15. Iron-depletion promotes mitophagy to maintain mitochondrial integrity in pathogenic yeast Candida glabrata

    PubMed Central

    Nagi, Minoru; Tanabe, Koichi; Nakayama, Hironobu; Ueno, Keigo; Yamagoe, Satoshi; Umeyama, Takashi; Ohno, Hideaki; Miyazaki, Yoshitsugu

    2016-01-01

    ABSTRACT Candida glabrata, a haploid budding yeast, is the cause of severe systemic infections in immune-compromised hosts. The amount of free iron supplied to C. glabrata cells during systemic infections is severely limited by iron-chelating proteins such as transferrin. Thus, the iron-deficiency response in C. glabrata cells is thought to play important roles in their survival inside the host's body. In this study, we found that mitophagy was induced under iron-depleted conditions, and that the disruption of a gene homologous to ATG32, which is responsible for mitophagy in Saccharomyces cerevisiae, blocked mitophagy in C. glabrata. The mitophagic activity in C. glabrata cells was not detected on short-period exposure to nitrogen-starved conditions, which is a mitophagy-inducing condition used in S. cerevisiae. The mitophagy-deficient atg32Δ mutant of C. glabrata also exhibited decreased longevity under iron-deficient conditions. The mitochondrial membrane potential in Cgatg32Δ cells was significantly lower than that in wild-type cells under iron-depleted conditions. In a mouse model of disseminated infection, the Cgatg32Δ strain resulted in significantly decreased kidney and spleen fungal burdens compared with the wild-type strain. These results indicate that mitophagy in C. glabrata occurs in an iron-poor host tissue environment, and it may contribute to the longevity of cells, mitochondrial quality control, and pathogenesis. PMID:27347716

  16. Disentangling metabolic pathways involved in copper resistance in Candida fukuyamaensis RCL-3 indigenous yeast.

    PubMed

    Irazusta, Verónica; Michel, Lucas; de Figueroa, Lucía I C

    2016-07-01

    Candida fukuyamaensis RCL-3 yeast strain isolated from a copper filter plant is able to lower copper concentration in culture medium. In the present study, effect of copper in proteins expression and mechanisms involved in copper resistance were explored using comparative proteomics. Mono-dimensional gel electrophoresis revealed differential band expressions between cells grown with or without copper. 2-DE analysis of C. fukuyamaensis RCL-3 revealed that copper exposure produced at least an over-expression of 40 proteins. Sixteen proteins were identified and grouped in four categories according to their functions: glycolysis and ATP production, synthesis of proteins, oxidative stress response, and processing and transport of proteins. Integral membrane proteins and membrane-associated proteins were analyzed, showing nine protein bands over-expressed in Cu-supplemented medium. Four proteins were identified, namely nucleoporin pom152, elongation factor 2, copper chaperone Sod1 Ccs1, and eiosome component Lsp1. The proteomic analysis performed allowed the identification of different metabolic pathways and certain proteins involved in metal input and storage related to cell ability to bioremediate copper. These proteins and mechanisms could be used for future applications of C. fukuyamaensis RCL-3 in biotechnological processes such as remediation of heavy metals.

  17. Komagataella populi sp. nov. and Komagataella ulmi sp. nov., two new methanol assimilating yeasts from exudates of deciduous trees.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Two new species of the methanol assimilating ascosporic yeast genus Komagataella are described. Komagataella populi sp. nov. (NRRL YB-455, CBS 12362, type strain) was isolated from an exudate on a cottonwood tree (Populus deltoides), Peoria, Illinois, USA, and Komagataella ulmi sp. nov. (NRRL YB-407...

  18. Novel Structural Features in Candida albicans Hyphal Glucan Provide a Basis for Differential Innate Immune Recognition of Hyphae Versus Yeast*

    PubMed Central

    Lowman, Douglas W.; Greene, Rachel R.; Bearden, Daniel W.; Kruppa, Michael D.; Pottier, Max; Monteiro, Mario A.; Soldatov, Dmitriy V.; Ensley, Harry E.; Cheng, Shih-Chin; Netea, Mihai G.; Williams, David L.

    2014-01-01

    The innate immune system differentially recognizes Candida albicans yeast and hyphae. It is not clear how the innate immune system effectively discriminates between yeast and hyphal forms of C. albicans. Glucans are major components of the fungal cell wall and key fungal pathogen-associated molecular patterns. C. albicans yeast glucan has been characterized; however, little is known about glucan structure in C. albicans hyphae. Using an extraction procedure that minimizes degradation of the native structure, we extracted glucans from C. albicans hyphal cell walls. 1H NMR data analysis revealed that, when compared with reference (1→3,1→6) β-linked glucans and C. albicans yeast glucan, hyphal glucan has a unique cyclical or “closed chain” structure that is not found in yeast glucan. GC/MS analyses showed a high abundance of 3- and 6-linked glucose units when compared with yeast β-glucan. In addition to the expected (1→3), (1→6), and 3,6 linkages, we also identified a 2,3 linkage that has not been reported previously in C. albicans. Hyphal glucan induced robust immune responses in human peripheral blood mononuclear cells and macrophages via a Dectin-1-dependent mechanism. In contrast, C. albicans yeast glucan was a much less potent stimulus. We also demonstrated the capacity of C. albicans hyphal glucan, but not yeast glucan, to induce IL-1β processing and secretion. This finding provides important evidence for understanding the immune discrimination between colonization and invasion at the mucosal level. When taken together, these data provide a structural basis for differential innate immune recognition of C. albicans yeast versus hyphae. PMID:24344127

  19. Using ammonium-tolerant yeast isolates: Candida halophila and Rhodotorula glutinis to treat high strength fermentative wastewater.

    PubMed

    Yang, Q; Yang, M; Hei, L; Zheng, S

    2003-03-01

    Two ammonium-tolerant yeast strains were isolated from sludge samples contaminated with monosodium glutamate manufacturing wastewater and were identified as Candida haplophila and Rhodotorula glutinis. The tolerance of the two yeast isolates to ammonia and their chemical oxygen demand (COD) removal perfomances were evaluated under batch and bench-scale conditions. The mixture of the two isolates was found to grow well in an artificial medium containing 25% (NH4)2SO4 and could effectively remove COD from monosodium glutamate wastewater even when the concentrations of NH4+-N and free NH3-N reached as high as 18,977 and 879 mg l(-1) respectively. A fixed-bed yeast reactor, which was initially inoculated with the yeast mixture, permitted a constant COD removal rate of over 80% during a period of near 2-month continuous running even when the influent COD was increased from 8,000 to 25,000 mg l(-1). The effluent was accompanied with suspended solids (SS) of over 4,500 mg l(-1), which was mainly composed of yeast cells and could be considered as a source of animal forage additive. The residual COD of effluents from the yeast reactor could be further reduced to under 500 mg l(-1) by a combination process of activated sludge treatment and coagulation technologies.

  20. Enantioselective reduction of acetophenone and its derivatives with a new yeast isolate Candida tropicalis PBR-2 MTCC 5158.

    PubMed

    Soni, Pankaj; Banerjee, Uttam Chand

    2006-01-01

    The enantioselective bioreduction of acetophenone and its various analogues has been carried out using a new yeast strain, Candida tropicalis MTCC 5158, to obtain the corresponding (S)-aryl ethanols with good yield and almost absolute enantioselectivity. The catalytic ability of this microbial strain for acetophenone reduction has been examined and also various parameters of the bioreduction reaction have been optimized. Studies on the catalytic performance showed that this microorganism is capable of carrying out the reduction in a broad range of pH (3-10) and temperature (25-40 degrees C), making it a more versatile biocatalyst. The preparative scale bioreduction of acetophenone using resting cells of Candida tropicalis yielded S-(-)-1-phenyl ethanol with 43% yield and >99% enantiomeric excess.

  1. Evaluation of PNA FISH® Yeast Traffic Light in identification of Candida species from blood and non-blood culture specimens.

    PubMed

    Radic, Marina; Goic-Barisic, Ivana; Novak, Anita; Rubic, Zana; Tonkic, Marija

    2016-08-01

    PNA FISH(®) (peptide nucleic acid fluorescent in situ hybridization) Yeast Traffic Light (PNA FISH(®) YTL) assay is a commercially avaliable method for rapid identification of Candida spp. directly from positive blood cultures. This report provides a one-year experience in identification of yeasts from 25 specimens (15 positive blood cultures and 10 other clinically significant specimens) using PNA FISH(®) YTL and comparing it to VITEK 2 System. Overall, assay identification compatibility with VITEK 2 System was found among 21/25 (84%) isolates tested. Only 3/25 (12%) of the isolates were not identified, and one isolate was misidentified by the PNA FISH(®) YTL assay. Our results show that the assay is a reliable method in identification of Candida spp. not only from blood cultures, but even from other clinically significant specimens (urine cultures, catheter tip cultures, peritoneal fluid cultures) when compared to automated method like VITEK 2 System. This novel application of the PNA FISH(®) YTL assay could therefore contribute to cost savings and significant benefit to patients, as rapid information about isolated yeast species is provided. PMID:27067303

  2. Evaluation of PNA FISH® Yeast Traffic Light in identification of Candida species from blood and non-blood culture specimens.

    PubMed

    Radic, Marina; Goic-Barisic, Ivana; Novak, Anita; Rubic, Zana; Tonkic, Marija

    2016-08-01

    PNA FISH(®) (peptide nucleic acid fluorescent in situ hybridization) Yeast Traffic Light (PNA FISH(®) YTL) assay is a commercially avaliable method for rapid identification of Candida spp. directly from positive blood cultures. This report provides a one-year experience in identification of yeasts from 25 specimens (15 positive blood cultures and 10 other clinically significant specimens) using PNA FISH(®) YTL and comparing it to VITEK 2 System. Overall, assay identification compatibility with VITEK 2 System was found among 21/25 (84%) isolates tested. Only 3/25 (12%) of the isolates were not identified, and one isolate was misidentified by the PNA FISH(®) YTL assay. Our results show that the assay is a reliable method in identification of Candida spp. not only from blood cultures, but even from other clinically significant specimens (urine cultures, catheter tip cultures, peritoneal fluid cultures) when compared to automated method like VITEK 2 System. This novel application of the PNA FISH(®) YTL assay could therefore contribute to cost savings and significant benefit to patients, as rapid information about isolated yeast species is provided.

  3. Mechanism of glucose and maltose transport in plasma-membrane vesicles from the yeast Candida utilis.

    PubMed Central

    van den Broek, P J; van Gompel, A E; Luttik, M A; Pronk, J T; van Leeuwen, C C

    1997-01-01

    Transport of glucose and maltose was studied in plasma-membrane vesicles from Candida utilis. The yeast was grown on a mixture of glucose and maltose in aerobic carbon-limited continuous cultures which enabled transport to be studied for both sugars with the same vesicles. Vesicles were prepared by fusion of isolated plasma membranes with proteoliposomes containing bovine heart cytochrome c oxidase as a proton-motive-force-generating system. Addition of reduced cytochrome c generated a proton-motive force, consisting of a membrane potential, negative inside, and a pH gradient, alkaline inside. Energization led to accumulation of glucose and maltose in these vesicles, reaching accumulation ratios of about 40-50. Accumulation also occurred in the presence of valinomycin or nigericin, but was prevented by a combination of the two ionophores or by uncoupler, showing that glucose and maltose transport are dependent on the proton-motive force. Comparison of sugar accumulation with quantitative data on the proton-motive force indicated a 1:1 H+/sugar stoichiometry for both transport systems. Efflux of accumulated glucose was observed on dissipation of the proton-motive force. Exchange and counterflow experiments confirmed the reversible character of the H+-glucose symporter. In contrast, uncoupler or a mixture of valinomycin plus nigericin induced only a slow efflux of accumulated maltose. Moreover under counterflow conditions, the expected transient accumulation was small. Thus the H+-maltose symporter has some characteristics of a carrier that is not readily reversible. It is concluded that in C. utilis the transport systems for glucose and maltose are both driven by the proton-motive force, but the mechanisms are different. PMID:9020885

  4. Methanol

    Integrated Risk Information System (IRIS)

    Methanol ; CASRN 67 - 56 - 1 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Effects )

  5. Characterization of a New Clinical Yeast Species, Candida tunisiensis sp. nov., Isolated from a Strain Collection from Tunisian Hospitals

    PubMed Central

    Eddouzi, Jamel; Hofstetter, Valérie; Groenewald, Marizeth; Manai, Mohamed

    2013-01-01

    From a collection of yeast isolates isolated from patients in Tunisian hospitals between September 2006 and July 2010, the yeast strain JEY63 (CBS 12513), isolated from a 50-year-old male that suffered from oral thrush, could not be identified to the species level using conventional methods used in clinical laboratories. These methods include matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS), germ tube formation, and the use of CHROMagar Candida and metabolic galleries. Sequence analysis of the nuclear rRNA (18S rRNA, 5.8S rRNA, and 26S rRNA) and internal transcribed spacer regions (ITS1 and ITS2) indicated that the ribosomal DNA sequences of this species were not yet reported. Multiple gene phylogenic analyses suggested that this isolate clustered at the base of the Dipodascaceae (Saccharomycetales, Saccharomycetes, and Ascomycota). JEY63 was named Candida tunisiensis sp. nov. according to several phenotypic criteria and its geographical origin. C. tunisiensis was able to grow at 42°C and does not form chlamydospores and hyphae but could grow as yeast and pseudohyphal forms. C. tunisiensis exhibited most probably a haploid genome with an estimated size of 10 Mb on at least three chromosomes. Using European Committee for Antimicrobial Susceptibility Testing (EUCAST) and Clinical and Laboratory Standards Institute (CLSI) Candida albicans susceptibility breakpoints as a reference, C. tunisiensis was resistant to fluconazole (MIC = 8 μg/ml), voriconazole (MIC = 0.5 μg/ml), itraconazole (MIC = 16 μg/ml), and amphotericin B (MIC = 4 μg/ml) but still susceptible to posaconazole (MIC = 0.008 μg/ml) and caspofungin (MIC = 0.5 μg/ml). In conclusion, MALDI-TOF MS permitted the early selection of an unusual isolate, which was still unreported in molecular databases but could not be unambiguously classified based on phylogenetic approaches. PMID:23077122

  6. Thrush and Other Candida Infections

    MedlinePlus

    ... these infections are caused by Candida albicans, a yeast-like fungus, although other species of Candida are ... in some cases. Teenaged girls who develop a yeast infection of the vagina and the surrounding area ...

  7. Outlines for the definition of halotolerance/halophily in yeasts: Candida versatilis (halophila) CBS4019 as the archetype?

    PubMed

    Silva-Graça, Magda; Neves, Luisa; Lucas, Cândida

    2003-06-01

    Candida versatilis (halophila) CBS4019 was chosen to study the physiological reactions of long-term exposure to extremely high salt concentrations. In general, our results show a significant increase in enzyme expression during growth under stress conditions. Although glycerol and mannitol pathways are not under glucose repression, they were found to be metabolically regulated. Glycerol-3P-dehydrogenase used either of its cofactors NADPH or NADH, being in favor of NADPH during growth with high salt concentrations. This ability of interchanging cofactors, an increased fermentation rate, and the observed mannitol pathway activity are suggested to contribute to the yeasts' redox stability. Enzymes per se were not salt-tolerant in vitro. Consistently, intracellular sodium was low and intracellular potassium, a requirement for growth, was high. The concept of halophily and its applicability to yeasts is discussed.

  8. Predictive value of oral colonization by Candida yeasts for the onset of a nosocomial infection in elderly hospitalized patients.

    PubMed

    Fanello, S; Bouchara, J P; Sauteron, M; Delbos, V; Parot, E; Marot-Leblond, A; Moalic, E; Le Flohicc, A M; Brangerd, B

    2006-02-01

    The incidence of nosocomial yeast infections has increased markedly in recent decades, especially among the elderly. The present study was therefore initiated not only to determine the predictive value of oral colonization by yeasts for the onset of a nosocomial Candida infection in elderly hospitalized patients (> 65 years), but also to clarify the factors that promote infection and to establish a relationship between the intensity of oral carriage and the onset of yeast infection. During this prospective cohort study, 256 patients (156 women and 100 men with a mean age of 83 +/- 8 years) were surveyed for yeast colonization or infection. Samples were collected every 4 days from day 0 to day 16 from four sites in the mouth, and intrinsic and extrinsic factors that might promote infection were recorded for each patient. Pulsed field gel electrophoresis was performed on Candida albicans isolates from all infected patients. Poor nutritional status was observed in 81 % of the patients and hyposalivation in 41 %. The colonization level was 67 % on day 0 (59 % C. albicans) and a heavy carriage of yeasts (> 50 c.f.u.) was observed for 51 % of the patients. The incidence of nosocomial colonization reached 6.9 % on day 4 (6.1 % on day 8 and 2.7 % on day 12), and that of nosocomial infection was 3.7 % on day 4 (6.8 % on day 8, 11.3 % on day 12 and 19.2 % on day 16). Of the 35 patients infected, 57 % were suffering from oral candidiasis. The principal risk factors for colonization were a dental prosthesis, poor oral hygiene and the use of antibiotics. The risk factors for infection, in addition to those already mentioned for colonization, were endocrine disease, poor nutritional status, prolonged hospitalization and high colony counts. Genotyping revealed person-to-person transmission in two patients. Thus, this study demonstrates a significant association between oral colonization and the onset of yeast infections in elderly hospitalized patients. Therefore, oral samples

  9. Candida, fluorescent stain (image)

    MedlinePlus

    This microscopic film shows a fluorescent stain of Candida. Candida is a yeast (fungus) that causes mild disease, but in immunocompromised individuals it may cause life-threatening illness. (Image ...

  10. Yeast Infections

    MedlinePlus

    Candida is the scientific name for yeast. It is a fungus that lives almost everywhere, including in ... infection that causes white patches in your mouth Candida esophagitis is thrush that spreads to your esophagus, ...

  11. Candida duobushaemulonii: an emerging rare pathogenic yeast isolated from recurrent vulvovaginal candidiasis in Brazil.

    PubMed

    Boatto, Humberto Fabio; Cavalcanti, Sarah Desirée Barbosa; Del Negro, Gilda Mb; Girão, Manoel João Bc; Francisco, Elaine Cristina; Ishida, Kelly; Gompertz, Olga Fischman

    2016-06-01

    The aim of this study was to identify Candida species isolated from women diagnosed with recurrent vulvovaginal candidiasis (RVVC) and their partners; and to evaluate the fluconazole (FLZ) susceptibility of the isolates. In a period of six years, among 172 patients diagnosed with vulvovaginal candidiasis, 13 women that presented RVVC and their partners were selected for this investigation. The isolates were obtained using Chromagar Candida medium, the species identification was performed by phenotypic and molecular methods and FLZ susceptibility was evaluated by E-test. Among 26 strains we identified 14 Candida albicans, six Candida duobushaemulonii, four Candida glabrata, and two Candida tropicalis. Agreement of the isolated species occurred in 100% of the couples. FLZ low susceptibility was observed for all isolates of C. duobushaemulonii (minimal inhibitory concentration values from 8-> 64 µg/mL), two C. glabrata isolates were FLZ-resistant and all C. albicans and C. tropicalis isolates were FLZ-susceptible. This report emphasises the importance of accurate identification of the fungal agents by a reliable molecular technique in RVVC episodes besides the lower antifungal susceptibility profile of this rare pathogen C. duobushaemulonii to FLZ.

  12. Candida duobushaemulonii: an emerging rare pathogenic yeast isolated from recurrent vulvovaginal candidiasis in Brazil

    PubMed Central

    Boatto, Humberto Fabio; Cavalcanti, Sarah Desirée Barbosa; Del Negro, Gilda MB; Girão, Manoel João BC; Francisco, Elaine Cristina; Ishida, Kelly; Gompertz, Olga Fischman

    2016-01-01

    The aim of this study was to identify Candida species isolated from women diagnosed with recurrent vulvovaginal candidiasis (RVVC) and their partners; and to evaluate the fluconazole (FLZ) susceptibility of the isolates. In a period of six years, among 172 patients diagnosed with vulvovaginal candidiasis, 13 women that presented RVVC and their partners were selected for this investigation. The isolates were obtained using Chromagar Candida medium, the species identification was performed by phenotypic and molecular methods and FLZ susceptibility was evaluated by E-test. Among 26 strains we identified 14Candida albicans, six Candida duobushaemulonii, four Candida glabrata, and twoCandida tropicalis. Agreement of the isolated species occurred in 100% of the couples. FLZ low susceptibility was observed for all isolates of C. duobushaemulonii (minimal inhibitory concentration values from 8-> 64 µg/mL), two C. glabrataisolates were FLZ-resistant and all C. albicans and C. tropicalis isolates were FLZ-susceptible. This report emphasises the importance of accurate identification of the fungal agents by a reliable molecular technique in RVVC episodes besides the lower antifungal susceptibility profile of this rare pathogen C. duobushaemulonii to FLZ. PMID:27304096

  13. Comparative Study of the New Colorimetric VITEK 2 Yeast Identification Card versus the Older Fluorometric Card and of CHROMagar Candida as a Source Medium with the New Card

    PubMed Central

    Aubertine, C. L.; Rivera, M.; Rohan, S. M.; Larone, D. H.

    2006-01-01

    The new VITEK 2 colorimetric card was compared to the previous fluorometric card for identification of yeast. API 20C was considered the “gold standard.” The new card consistently performed better than the older card. Isolates from CHROMagar Candida plates were identified equally as well as those from Sabouraud dextrose agar. PMID:16390976

  14. CHARACTERIZATION OF THE ALKANE-INDUCIBLE CYTOCHROME P450 (P450ALK) GENE FROM THE YEAST CANDIDA TROPICALIS: IDENTIFICATION OF A NEW P450 FAMILY

    EPA Science Inventory

    The P450alk gene, which is inducible by the assimilation of alkane in Candida tropicalis, was sequenced and characterized. Structural features described in promoter and terminator regions of Saccharomyces yeast genes are present in the P450alk gene and some particular structures ...

  15. In vivo assessing of nanometric changes on the surface of whole tomatoes that have been inoculated with Candida guilliermondii yeast.

    PubMed

    Infante, Esperanza Del Pilar

    2014-08-01

    The cuticle of plants that covers the epidermis of cells, an interface between the fruit and the environment, has an important role to play in fruit quality because it prevents water loss and mechanical damage while simultaneously forming a barrier as it prevents phytopathogens from entering the fruit. All these factors give rise to flaws in the appearance of the fruit, thus contributing to marketing problems in the form of financial loss. In the search for solutions to some of these problems, certain biocontrolling yeasts have been introduced in the last few years. In the study described here, the changes observed on the surface of the whole tomato were evaluated in vivo during the first 72 h after inoculation by spraying Candida guilliermondii yeast onto the fruit's surface. The measurements were taken on a nanometric scale using atomic force microscopy; images were created in both contact and tapping modes. The results showed diminished roughness of the surface, which could contribute to reduced phytopathogen adherence due to the thinner contact area. These results furthermore showed that a yeast biofilm was formed on the fruit which probably helps to improve water retention inside the fruit. PMID:24913139

  16. Candida famata (Candida flareri).

    PubMed

    Dmytruk, Kostyantyn V; Sibirny, Andriy A

    2012-11-01

    Candida famata (Candida flareri) belongs to the group of so-called 'flavinogenic yeasts', capable of riboflavin oversynthesis under condition of iron starvation. Some strains of C. famata belong to the most flavinogenic organisms known and were used for industrial production of riboflavin for a long time in the USA. C. famata is characterized by high salt tolerance, growing at NaCl concentrations of up to 2.5  M. Development of basic tools for the metabolic engineering of C. famata, such as a transformation system, selective markers, insertional mutagenesis, a reporter system and others, are described. The developed tools were used for cloning and identification of structural and regulatory genes of riboflavin synthesis. The construction of improved yeast strains producing riboflavin, FMN and FAD, based on the industrial riboflavin-producing strain dep8 and its non-reverting analogue AF4, is also described. PMID:23108915

  17. Scanning electron microscopy as a tool for the analysis of colony architecture produced by phenotypic switching of a human pathogenic yeast Candida tropicalis

    NASA Astrophysics Data System (ADS)

    Furlaneto, M. C.; Andrade, C. G. T. J.; Aragão, P. H. A.; França, E. J. G.; Moralez, A. T. P.; Ferreira, L. C. S.

    2012-07-01

    Candida tropicalis has been identified as one of the most prevalent pathogenic yeast species of the Candida-non-albicans group. Phenotypic switching is a biological phenomenon related to the occurrence of spontaneous emergence of colonies with different morphologies that provides variability within colonizing populations in order to adapt to different environments. Currently, studies of the microstructure of switching variant colonies are not subject of extensive research. SEM analysis was used to verify the architecture of whole Candida colonies. The strain 49/07 exhibited a hemispherical shape character, while the strain 335/07 showed a volcano shape with mycelated-edge colony. The ring switch variant is characterized by a highly wrinkled centre and an irregular periphery. The rough phenotype exhibited a three-dimensional architecture and was characterized by the presence of deep central and peripheral depressions areas. The ultrastructural analysis also allowed the observation of the arrangement of individual cells within the colonies. The whole smooth colony consisted entirely of yeast cells. Differently, aerial filaments were found all around the colony periphery of the volcano shape colony. For this colony type the mycelated-edge consisted mainly of hyphae, although yeast cells are also seen. The ring and rough colonies phenotypes comprised mainly yeast cells with the presence of extracellular material connecting neighbouring cells. This study has shown that SEM can be used effectively to examine the microarchitecture of colonies morphotypes of the yeast C. tropicalis and further our understanding of switching event in this pathogen.

  18. Utilization of xylan by yeasts and its conversion to ethanol by Pichia stipitis strains. [Cryptococcus; Pichia stipitis; Candida shehatae

    SciTech Connect

    Lee, H.; Biely, P.; Latta, R.K.; Barbosa, M.F.S.; Schneider, H.

    1986-08-01

    Yeasts able to grow on D-xylose were screened for the ability to hydrolyze xylan. Xylanase activity was found to be rare; a total of only 19 of more than 250 strains yielded a positive test result. The activity was localized largely in the genus Cryptococcus and in Pichia stipitis and its anamorph Candida shehatae. The ability to hydrolyze xylan was generally uncoupled from that to hydrolyze cellulose; only three of the xylan-positive strains also yielded a positive test for cellulolytic activity. Of the 19 xylanolytic strains. 2. P. stipitis CBS 5773 and CBS 5775, converted xylan into ethanol, with about 60% of a theoretical yield computed on the basis of the amount of D-xylose present originally that could be released by acid hydrolysis.

  19. [Prevention and control of nosocomial and health-care facilities associated infections caused by species of Candida and other yeasts].

    PubMed

    Pemán, Javier; Zaragoza, Rafael; Salavert, Miguel

    2013-12-01

    Knowledge of the epidemiology of invasive fungal diseases caused by yeasts (Candida spp., especially) in health care settings allows the establishment of the levels necessary for its prevention. A first step is to identify groups of patients at high risk of nosocomial invasive fungal infections, establish accurate risk factors, observing the periods of greatest risk, and analyze the epidemiological profile in genera and species as well as the patterns of antifungal resistance. Secondly, mechanisms to avoid persistent exposure to potential fungal pathogens must be programed, protecting areas and recommending measures such as the control of the quality of the air and water, inside and outside the hospital, and other products or substances able to cause outbreaks. Finally, apart from the correct implementation of these measures, in selected patients at very high risk, the use of antifungal prophylaxis should be considered following the guidelines published.

  20. Efficient simultaneous saccharification and fermentation of agricultural residues by Saccharomyces cerevisiae and Candida shehatae. The D-xylose fermenting yeast.

    PubMed

    Palnitkar, S S; Lachke, A H

    1990-11-01

    Simultaneous Saccharification and Fermentation (SSF) experiments were carried out on agricultural residues using culture filtrate of Sclerotium rolfsii, which produces high levels of cellulases and hemicellulases for the saccharification of rice straw and bagasse, and Candida shehatae--the D-xylose fermenting yeast, and Saccharomyces cerevisiae, both separately and in coculture, for fermenting the released sugars. The coculture system showed efficient utilization of hydrolyzed sugars with 30-38% and 10-13% increase in ethanol production as compared to C. shehatae and S. cerevisiae, respectively, when cultivated separately. SSF simulation studies were carried out using standard sugar mixtures of glucose, xylose, and cellobiose. Both organisms could not use cellobiose, whereas glucose was used preferentially. C. shehatae was capable of utilizing xylose in the presence of glucose. PMID:2091527

  1. Yeast communities in Sphagnum phyllosphere along the temperature-moisture ecocline in the boreal forest-swamp ecosystem and description of Candida sphagnicola sp. nov.

    PubMed

    Kachalkin, Aleksey V; Yurkov, Andrey M

    2012-06-01

    The effects of the temperature-moisture factors on the phylloplane yeast communities inhabiting Sphagnum mosses were studied along the transition from a boreal forest to a swamp biotope at the Central Forest State Biosphere Reserve (Tver region, Russia). We tested the hypothesis that microclimatic parameters affect yeast community composition and structure even on a rather small spatial scale. Using a conventional plating technique we isolated and identified by molecular methods a total of 15 species of yeasts. Total yeast counts and species richness values did not depend on environmental factors, although yeast community composition and structure did. On average, Sphagnum in the swamp biotope supported a more evenly structured yeast community. Relative abundance of ascomycetous yeasts was significantly higher on swamp moss. Rhodotorula mucilaginosa dominated in the spruce forest and Cryptococcus magnus was more abundant in the swamp. Our study confirmed the low occurrence of tremellaceous yeasts in the Sphagnum phyllosphere. Of the few isolated ascomycetous yeast and yeast-like species, some were differentiated from hitherto known species in physiological tests and phylogenetic analyses. We describe one of them as Candida sphagnicola and designate KBP Y-3887(T) (=CBS 11774(T) = VKPM Y-3566(T) = MUCL 53590(T)) as the type strain. The new species was registered in MycoBank under MB 563443.

  2. Genome-scale metabolic modeling and in silico analysis of lipid accumulating yeast Candida tropicalis for dicarboxylic acid production.

    PubMed

    Mishra, Pranjul; Park, Gyu-Yeon; Lakshmanan, Meiyappan; Lee, Hee-Seok; Lee, Hongweon; Chang, Matthew Wook; Ching, Chi Bun; Ahn, Jungoh; Lee, Dong-Yup

    2016-09-01

    Recently, the bio-production of α,ω-dicarboxylic acids (DCAs) has gained significant attention, which potentially leads to the replacement of the conventional petroleum-based products. In this regard, the lipid accumulating yeast Candida tropicalis, has been recognized as a promising microbial host for DCA biosynthesis: it possess the unique ω-oxidation pathway where the terminal carbon of α-fatty acids is oxidized to form DCAs with varying chain lengths. However, despite such industrial importance, its cellular physiology and lipid accumulation capability remain largely uncharacterized. Thus, it is imperative to better understand the metabolic behavior of this lipogenic yeast, which could be achieved by a systems biological approach. To this end, herein, we reconstructed the genome-scale metabolic model of C. tropicalis, iCT646, accounting for 646 unique genes, 945 metabolic reactions, and 712 metabolites. Initially, the comparative network analysis of iCT646 with other yeasts revealed several distinctive metabolic reactions, mainly within the amino acid and lipid metabolism including the ω-oxidation pathway. Constraints-based flux analysis was, then, employed to predict the in silico growth rates of C. tropicalis which are highly consistent with the cellular phenotype observed in glucose and xylose minimal media chemostat cultures. Subsequently, the lipid accumulation capability of C. tropicalis was explored in comparison with Saccharomyces cerevisiae, indicating that the formation of "citrate pyruvate cycle" is essential to the lipid accumulation in oleaginous yeasts. The in silico flux analysis also highlighted the enhanced ability of pentose phosphate pathway as NADPH source rather than malic enzyme during lipogenesis. Finally, iCT646 was successfully utilized to highlight the key directions of C. tropicalis strain design for the whole cell biotransformation application to produce long-chain DCAs from alkanes. Biotechnol. Bioeng. 2016;113: 1993-2004.

  3. Persistent colonization of Candida albicans yeast on the tongue in NOD/SCID.e2f1-/- mice.

    PubMed

    Arai, Toshiaki; Kinoshita, Yosuke; Senpuku, Hidenobu

    2015-05-01

    Candida albicans is a commensal fungus that commonly colonizes as opportunistic pathogens human mucosal surfaces. Our aim was to observe persistent infection of C. albicans on the tongue in NOD/SCID.e2f1(-/-) mice, which naturally was decreased saliva and undeveloped T and B cells. Using a cotton swab, a C. albicans suspension was applied to the tongue of wild type and mutant mice after disinfection using 0.2% Chlorhexidine (CHX). In our earlier report, it was found that many times inoculation per day and consecutive day inoculations without disinfection of indigenous microorganisms did not induce significant C. albicans infection for 48 h in the oral cavity. In this study, using inoculation of four sets {one inoculation after disinfection by CHX + interval (3 or 4 d)} induced longer term and higher numbers infection for 4 days on the tongue than results in a previous report in both NOD/SCID.e2f1(+/+) and NOD/SCID.e2f1(-/-) mice. Repeat of disinfection to indigenous microorganisms and inoculation with interval established and realized a new model for persistent infection of C. albicans yeast. However, decreased saliva and consecutive inoculations per day did not contribute to the persistent colonization on the tongue in the mice. It is suggested that the interaction between C. albicans and indigenous microorganisms is important for persistent colonization of C. albicans yeast on the tongue rather than decreased saliva in the oral cavity.

  4. Fermentation of soybean oil deodorizer distillate with Candida tropicalis to concentrate phytosterols and to produce sterols-rich yeast cells.

    PubMed

    Zhao, Guoqun; Hu, Tao; Zhao, Lihua

    2014-03-01

    Phytosterols have been recovered from the deodorizer distillate produced in the final deodorization step of vegetable oil refining by various processes. The deodorizer distillate contains mainly free fatty acids (FFAs), phytosterols, and tocopherols. The presence of FFAs hinders recovery of phytosterols. In this study, fermentation of soybean oil deodorizer distillate (SODD) with Candida tropicalis 1253 was carried out. FFAs were utilized as carbon source and converted into cellular components as the yeast cells grew. Phytosterols concentration in SODD increased from 15.2 to 28.43 % after fermentation. No significant loss of phytosterols was observed during the process. Microbial fermentation of SODD is a potential approach to concentrate phytosterols before the recovery of phytosterols from SODD. During SODD fermentation, sterols-rich yeast cells were produced and the content of total sterols was as high as 6.96 %, but its major sterol was not ergosterol, which is the major sterol encountered in Saccharomyces cerevisiae. Except ergosterol, other sterols synthesized in the cells need to be identified. PMID:24297326

  5. Metabolic gene clusters encoding the enzymes of two branches of the 3-oxoadipate pathway in the pathogenic yeast Candida albicans.

    PubMed

    Gérecová, Gabriela; Neboháčová, Martina; Zeman, Igor; Pryszcz, Leszek P; Tomáška, Ľubomír; Gabaldón, Toni; Nosek, Jozef

    2015-05-01

    The pathogenic yeast Candida albicans utilizes hydroxyderivatives of benzene via the catechol and hydroxyhydroquinone branches of the 3-oxoadipate pathway. The genetic basis and evolutionary origin of this catabolic pathway in yeasts are unknown. In this study, we identified C. albicans genes encoding the enzymes involved in the degradation of hydroxybenzenes. We found that the genes coding for core components of the 3-oxoadipate pathway are arranged into two metabolic gene clusters. Our results demonstrate that C. albicans cells cultivated in media containing hydroxybenzene substrates highly induce the transcription of these genes as well as the corresponding enzymatic activities. We also found that C. albicans cells assimilating hydroxybenzenes cope with the oxidative stress by upregulation of cellular antioxidant systems such as alternative oxidase and catalase. Moreover, we investigated the evolution of the enzymes encoded by these clusters and found that most of them share a particularly sparse phylogenetic distribution among Saccharomycotina, which is likely to have been caused by extensive gene loss. We exploited this fact to find co-evolving proteins that are suitable candidates for the missing enzymes of the pathway. PMID:25743787

  6. Species-specific activation of Cu/Zn SOD by its CCS copper chaperone in the pathogenic yeast Candida albicans.

    PubMed

    Gleason, Julie E; Li, Cissy X; Odeh, Hana M; Culotta, Valeria C

    2014-06-01

    Candida albicans is a pathogenic yeast of important public health relevance. Virulence of C. albicans requires a copper and zinc containing superoxide dismutase (SOD1), but the biology of C. albicans SOD1 is poorly understood. To this end, C. albicans SOD1 activation was examined in baker's yeast (Saccharomyces cerevisiae), a eukaryotic expression system that has proven fruitful for the study of SOD1 enzymes from invertebrates, plants, and mammals. In spite of the 80% similarity between S. cerevisiae and C. albicans SOD1 molecules, C. albicans SOD1 is not active in S. cerevisiae. The SOD1 appears incapable of productive interactions with the copper chaperone for SOD1 (CCS1) of S. cerevisiae. C. albicans SOD1 contains a proline at position 144 predicted to dictate dependence on CCS1. By mutation of this proline, C. albicans SOD1 gained activity in S. cerevisiae, and this activity was independent of CCS1. We identified a putative CCS1 gene in C. albicans and created heterozygous and homozygous gene deletions at this locus. Loss of CCS1 resulted in loss of SOD1 activity, consistent with its role as a copper chaperone. C. albicans CCS1 also restored activity to C. albicans SOD1 expressed in S. cerevisiae. C. albicans CCS1 is well adapted for activating its partner SOD1 from C. albicans, but not SOD1 from S. cerevisiae. In spite of the high degree of homology between the SOD1 and CCS1 molecules in these two fungal species, there exists a species-specific barrier in CCS-SOD interactions which may reflect the vastly different lifestyles of the pathogenic versus the noninfectious yeast.

  7. Gene engineering in yeast for biodegradation: Immunological cross-reactivity among cytochrome p-450 system proteins of saccharomyces cerevisiae and candida tropicalis

    SciTech Connect

    Loper, J.C.; Chen, C.; Dey, C.R.

    1993-01-01

    Yeasts are eukaryotic microorganisms whose cytochrome P-450 monooxygenase systems may be amenable to genetic engineering for the hydroxylation and detoxication of polychlorinated aromatic hydrocarbons. The molecular genetic properties of strains of bakers yeast, Saccharomyces cerevisiae, and an n-alkane utilizing yeast, Candida tropicalis ATCC750 are examined. Standard methods were used to purify cytochrome P-450 and NADPH-cytochrome c (P-450) reductase proteins from cells cultured by semi-anaerobic glucose fermentation (S. cerevisiae, C. tropicalis) and by growth on tetradecane (C. tropicalis). Polyvalent antisera prepared in rabbits to some of these proteins were used in tests of immunological relatedness among the purified proteins using sodium dodecyl sulfate-polyacrylamide gel electrophoresis and nitrocellulose filter immunoblots. The results provide evidence for gene relationships which should prove useful in gene isolation and subsequent engineering of P-450 enzyme systems in yeast.

  8. Formation of irregular giant peroxisomes by overproduction of the crystalloid core protein methanol oxidase in the methylotrophic yeast Hansenula polymorpha.

    PubMed Central

    Roggenkamp, R; Didion, T; Kowallik, K V

    1989-01-01

    The crystalloid core in peroxisomes of the methylotrophic yeast Hansenula polymorpha is composed of the octameric flavoprotein methanol oxidase (MOX). We transformed yeast cells with a high-copy-number vector harboring the cloned MOX gene in order to study the effects on regulation, protein import, and peroxisome biosynthesis. In transformed wild-type cells, no increase in expression of MOX was detectable. Mutants defective in MOX activity were isolated by a specific selection procedure. Two structural MOX mutants are described that allow overproduction of a fully active enzyme upon transformation at quantities of about two-thirds of the total cellular protein. The overproduced protein was imported into peroxisomes, altering their morphology (in thin sections) and stability in cell lysates; the organelles showed a tendency to form rectangular bodies, and their lumina were completely filled with the crystalloid structure. The overall size of the peroxisomes was increased severalfold in comparison with the size of nontransformed yeast cells. The results suggest high capacities of peroxisomal growth conferred by overproduction and import of a single protein. Images PMID:2657394

  9. Study on the substituents' effects of a series of synthetic chalcones against the yeast Candida albicans.

    PubMed

    Batovska, D; Parushev, St; Slavova, A; Bankova, V; Tsvetkova, I; Ninova, M; Najdenski, H

    2007-01-01

    A large series of chalcones were synthesized and studied for activity against Candida albicans. The SAR analysis showed that the antifungal activity was highly dependent on the substitution pattern of the aryl rings and correlated to a large extent with the ability of compounds to interact with sulfhydryl groups. The most active were the hydroxylated chalcones as their activity related to the location of the phenolic group in the aryl ring B as follows: o-OH>p-OH approximately 3,4-di-OH>m-OH. These and other correlations obtained strongly contribute to the knowledge for design of anticandidal chalcones. PMID:17007965

  10. Lindane degradation by Candida VITJzN04, a newly isolated yeast strain from contaminated soil: kinetic study, enzyme analysis and biodegradation pathway.

    PubMed

    Salam, Jaseetha Abdul; Das, Nilanjana

    2014-04-01

    A new yeast strain was isolated from sugarcane cultivation field which was able to utilize lindane as sole carbon source for growth in mineral medium. The yeast was identified and named as Candida sp. VITJzN04 based on a polyphasic approach using morphological, biochemical and 18S rDNA, D1/D2 and ITS sequence analysis. The isolated yeast strain efficiently degraded 600 mg L⁻¹ of lindane within 6 days in mineral medium under the optimal conditions (pH 7; temperature 30 °C and inoculum dosage 0.06 g L⁻¹) with the least half-life of 1.17 days and degradation constant of 0.588 per day. Lindane degradation was tested with various kinetic models and results revealed that the reaction could be described best by first-order and pseudo first-order models. In addition, involvement of the enzymes viz. dechlorinase, dehalogenase, dichlorohydroquinone reductive dechlorinase, lignin peroxidase and manganese peroxidase was noted during lindane degradation. Addition of H2O2 in the mineral medium showed 32 % enhancement of lindane degradation within 3 days. Based on the metabolites identified by GC-MS and FTIR analysis, sequential process of lindane degradation by Candida VITJzN04 was proposed. To the best of our knowledge, this is the first report of isolation and characterization of lindane-degrading Candida sp. and elucidation of enzyme systems during the degradation process.

  11. Activity of Isavuconazole and Other Azoles against Candida Clinical Isolates and Yeast Model Systems with Known Azole Resistance Mechanisms

    PubMed Central

    Coste, Alix T.

    2015-01-01

    Isavuconazole is a novel, broad-spectrum, antifungal azole. In order to evaluate its interactions with known azole resistance mechanisms, isavuconazole susceptibility among different yeast models and clinical isolates expressing characterized azole resistance mechanisms was tested and compared to those of fluconazole, itraconazole, posaconazole, and voriconazole. Saccharomyces cerevisiae expressing the Candida albicans and C. glabrata ATP binding cassette (ABC) transporters (CDR1, CDR2, and CgCDR1), major facilitator (MDR1), and lanosterol 14-α-sterol-demethylase (ERG11) alleles with mutations were used. In addition, pairs of C. albicans and C. glabrata strains from matched clinical isolates with known azole resistance mechanisms were investigated. The expression of ABC transporters increased all azole MICs, suggesting that all azoles tested were substrates of ABC transporters. The expression of MDR1 did not increase posaconazole, itraconazole, and isavuconazole MICs. Relative increases of azole MICs (from 4- to 32-fold) were observed for fluconazole, voriconazole, and isavuconazole when at least two mutations were present in the same ERG11 allele. Upon MIC testing of azoles with clinical C. albicans and C. glabrata isolates with known resistance mechanisms, the MIC90s of C. albicans for fluconazole, voriconazole, itraconazole, posaconazole, and isavuconazole were 128, 2, 1, 0.5, and 2 μg/ml, respectively, while in C. glabrata they were 128, 2, 4, 4, and 16 μg/ml, respectively. In conclusion, the effects of azole resistance mechanisms on isavuconazole did not differ significantly from those of other azoles. Resistance mechanisms in yeasts involving ABC transporters and ERG11 decreased the activity of isavuconazole, while MDR1 had limited effect. PMID:26482310

  12. Reclassification of the Candida haemulonii complex as Candida haemulonii (C. haemulonii group I), C. duobushaemulonii sp. nov. (C. haemulonii group II), and C. haemulonii var. vulnera var. nov.: three multiresistant human pathogenic yeasts.

    PubMed

    Cendejas-Bueno, E; Kolecka, A; Alastruey-Izquierdo, A; Theelen, B; Groenewald, M; Kostrzewa, M; Cuenca-Estrella, M; Gómez-López, A; Boekhout, T

    2012-11-01

    The Candida haemulonii species complex is currently known as C. haemulonii groups I and II. Here we describe C. haemulonii group II as a new species, Candida duobushaemulonii sp. nov., and C. haemulonii var. vulnera as new a variety of C. haemulonii group I using phenotypic and molecular methods. These taxa and other relatives of C. haemulonii (i.e., Candida auris and Candida pseudohaemulonii) cannot be differentiated by the commercial methods now used for yeast identification. Four isolates (C. haemulonii var. vulnera) differed from the other isolates of C. haemulonii in the sequence of the internal transcribed spacer (ITS) regions of the nuclear rRNA gene operon. The new species and the new variety have a multiresistant antifungal profile, which includes high MICs of amphotericin B (geometric mean MIC, 1.18 mg/liter for C. haemulonii var. vulnera and 2 mg/liter for C. duobushaemulonii sp. nov) and cross-resistance to azole compounds. Identification of these species should be based on molecular methods, such as sequence analysis of ITS regions and matrix-assisted laser desorption ionization-time of flight mass spectrometry.

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

    SciTech Connect

    Sampathkumar, Parthasarathy; Kim, Seung Joong; Manglicmot, Danalyn; Bain, Kevin T.; Gilmore, Jeremiah; Gheyi, Tarun; Phillips, Jeremy; Pieper, Ursula; Fernandez-Martinez, Javier; Franke, Josef D.; Matsui, Tsutomu; Tsuruta, Hiro; Atwell, Shane; Thompson, Devon A.; Emtage, J. Spencer; Wasserman, Stephen R.; Rout, Michael P.; Sali, Andrej; Sauder, J. Michael; Almo, Steven C.; Burley, Stephen K.

    2012-10-23

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

  14. Atomic Structure of the Nuclear Pore Complex targeting domain of a Nup116 homologue from the yeast, Candida glabrata

    PubMed Central

    Sampathkumar, Parthasarathy; Kim, Seung Joong; Manglicmot, Danalyn; Bain, Kevin T.; Gilmore, Jeremiah; Gheyi, Tarun; Phillips, Jeremy; Pieper, Ursula; Fernandez-Martinez, Javier; Franke, Josef D.; Matsui, Tsutomu; Tsuruta, Hiro; Atwell, Shane; Thompson, Devon A.; Emtage, J. Spencer; Wasserman, Stephen R.; Rout, Michael P.; Sali, Andrej; Sauder, J. Michael; Almo, Steven C.; Burley, Stephen K.

    2012-01-01

    The nuclear pore complex (NPC), embedded in the nuclear envelope, is a large, dynamic molecular assembly that facilitates exchange of macromolecules between the nucleus and cytoplasm. The yeast NPC is an eight-fold symmetric annular structure composed of ~456 polypeptide chains contributed by ~30 distinct proteins termed nucleoporins (Nups). Nup116, identified only in fungi, plays a central role in both protein import and mRNA export through the NPC. Nup116 is a modular protein with N-terminal “FG” repeats containing a Gle2p-binding sequence motif (GLEBS motif) and a NPC targeting domain at its C-terminus. We report the crystal structure of the NPC targeting domain of Candida glabrata Nup116, consisting of residues 882-1034 [CgNup116(882-1034)], at 1.94 Å resolution. The X-ray structure of CgNup116(882-1034) is consistent with the molecular envelope determined in solution by Small Angle X-ray Scattering (SAXS). Structural similarities of CgNup116(882-1034) with homologous domains from Saccharomyces cerevisiae Nup116, S. cerevisiaeNup145N, and human Nup98 are discussed. PMID:22544723

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

    PubMed

    Sampathkumar, Parthasarathy; Kim, Seung Joong; Manglicmot, Danalyn; Bain, Kevin T; Gilmore, Jeremiah; Gheyi, Tarun; Phillips, Jeremy; Pieper, Ursula; Fernandez-Martinez, Javier; Franke, Josef D; Matsui, Tsutomu; Tsuruta, Hiro; Atwell, Shane; Thompson, Devon A; Emtage, J Spencer; Wasserman, Stephen R; Rout, Michael P; Sali, Andrej; Sauder, J Michael; Almo, Steven C; Burley, Stephen K

    2012-08-01

    The nuclear pore complex (NPC), embedded in the nuclear envelope, is a large, dynamic molecular assembly that facilitates exchange of macromolecules between the nucleus and the cytoplasm. The yeast NPC is an eightfold symmetric annular structure composed of ~456 polypeptide chains contributed by ~30 distinct proteins termed nucleoporins. Nup116, identified only in fungi, plays a central role in both protein import and mRNA export through the NPC. Nup116 is a modular protein with N-terminal "FG" repeats containing a Gle2p-binding sequence motif and a NPC targeting domain at its C-terminus. We report the crystal structure of the NPC targeting domain of Candida glabrata Nup116, consisting of residues 882-1034 [CgNup116(882-1034)], at 1.94 Å resolution. The X-ray structure of CgNup116(882-1034) is consistent with the molecular envelope determined in solution by small-angle X-ray scattering. Structural similarities of CgNup116(882-1034) with homologous domains from Saccharomyces cerevisiae Nup116, S. cerevisiae Nup145N, and human Nup98 are discussed. PMID:22544723

  16. A dual labelling method for measuring uptake of low molecular weight compounds into the pathogenic yeast Candida albicans.

    PubMed

    Ziegelbauer, K

    1998-10-01

    In contrast to other eukaryotic cells the pathogenic yeast Candida albicans is resistant to many structurally unrelated metabolic inhibitors. Reduced permeability due to the cell wall and/or altered plasma membrane composition is thought to be at least partly responsible for this phenomenon. To study the uptake of low molecular weight compounds into C. albicans we developed a dual labelling method. Intact cells, metabolically inactivated cells, spheroplasts or membrane fragments of C. albicans were incubated with various [14C]-labelled compound in the presence of [3H]-labelled water. After separation of cells and supernatant isotope ratios [3H]/[14C] were determined. Quotients of the isotope ratios from cells and supernatant, called enrichment coefficients, were calculated under all four conditions. The enrichment coefficients indicated whether a compound can enter C. albicans cells, is trapped within the cell wall, is enriched in the lipophilic membrane compartment, is actively accumulated or actively exported by multidrug resistance carriers. We used six structurally unrelated compounds to test our method. We found no evidence for a general impermeability of C. albicans.

  17. Cytochrome P450 complement (CYPome) of Candida oregonensis, a gut-associated yeast of bark beetle, Dendroctonus rhizophagus.

    PubMed

    Hernández-Martínez, Fabiola; Briones-Roblero, Carlos Iván; Nelson, David R; Rivera-Orduña, Flor Nohemí; Zúñiga, Gerardo

    2016-09-01

    Bark beetles (Curculionidae: Scolytinae) and associated microorganisms must overcome a complex tree's defence system, which includes toxic monoterpenes, to successfully complete their life cycle. A number of studies have suggested these microorganisms could have ecological roles related with the nutrition, detoxification, and semiochemical production. In particular, in filamentous fungi symbionts, cytochrome P450 (CYP) have been involved with terpenoid detoxification and biotransformation processes. Candida oregonensis has been isolated from the gut, ovaries, and frass of different bark beetle species, and it is a dominant species in the Dendroctonus rhizophagus gut. In this study, we identify, characterise, and infer the phylogenetic relationships of C. oregonensis CYP genes. The results indicate that the cytochrome P450 complement (CYPome) is composed of nine genes (CYP51F1, CYP61A1, CYP56D1, CYP52A59, CYP52A60, CYP52A61, CYP52A62, CYP5217A8, and CYP5217B1), which might participate in primary metabolic reactions such as sterol biosynthesis, biodegradation of xenobiotic, and resistance to environmental stress. The prediction of the cellular location suggests that these CYPs to be anchored to the plasma membrane, membranes of the endoplasmic reticulum, mitochondria, and peroxisomes. These findings lay the foundation for future studies about the functional role of P450s, not only for yeasts, but also for the insects with which they interact. PMID:27567714

  18. Molecular cloning and characterization of a Candida tsukubaensis alpha-glucosidase gene in the yeast Saccharomyces cerevisiae.

    PubMed

    Kinsella, B T; Larkin, A; Bolton, M; Cantwell, B A

    1991-07-01

    The molecular cloning of an alpha-glucosidase gene isolated from a Candida tsukubaensis (CBS 6389) genomic library in Saccharomyces cervisiae is reported. The cloned gene is contained within a 6.2 kb Sau3A DNA fragment and directs the synthesis and secretion of an amylolytic enzyme into the extracellular medium of the recombinant host, S. cerevisiae. The cloned enzyme was found to have an unusually broad substrate specificity and is capable of hydrolysing alpha-1,2, alpha-1,3, alpha-1,4 and alpha-1,6 linked, as well as aryl and alkyl, D-glucosides. On the basis of its substrate specificity profile, the cloned enzyme was classified as an alpha-glucosidase (E.C. 3.2.1.20). It has a pH optimum in the range 4.2-4.6, a temperature optimum of 58 degrees C and is readily inactivated at pasteurization temperature (60 degrees C). Southern blot analysis failed to reveal any homology between the cloned gene and genomic DNA isolated from other well characterized amylolytic yeasts. A rapid plate-assay, based on the utilization of a chromogenic substrate X-alpha-D-glucoside to detect the expression of the cloned alpha-glucosidase in S. cerevisiae transformants, was developed. PMID:1934116

  19. Detoxification of Eucheuma spinosum Hydrolysates with Activated Carbon for Ethanol Production by the Salt-Tolerant Yeast Candida tropicalis.

    PubMed

    Ra, Chae Hun; Jung, Jang Hyun; Sunwoo, In Young; Kang, Chang Han; Jeong, Gwi-Taek; Kim, Sung-Koo

    2015-06-01

    The objective of this study was to optimize the slurry contents and salt concentrations for ethanol production from hydrolysates of the seaweed Eucheuma spinosum. A monosaccharide concentration of 44.2 g/l as 49.6% conversion of total carbohydrate of 89.1 g/l was obtained from 120 g dw/l seaweed slurry. Monosaccharides from E. spinosum slurry were obtained by thermal acid hydrolysis and enzymatic hydrolysis. Addition of activated carbon at 2.5% (w/v) and the adsorption time of 2 min were used in subsequent adsorption treatments to prevent the inhibitory effect of HMF. The adsorption surface area of the activated carbon powder was 1,400-1,600 m(2)/g and showed selectivity to 5-hydroxymethyl furfural (HMF) from monosaccharides. Candida tropicalis KCTC 7212 was cultured in yeast extract, peptone, glucose, and high-salt medium, and exposed to 80, 90, 100, and 110 practical salinity unit (psu) salt concentrations in the lysates. The 100 psu salt concentration showed maximum cell growth and ethanol production. The ethanol fermentations with activated carbon treatment and use of C. tropicalis acclimated to a high salt concentration of 100 psu produced 17.9 g/l of ethanol with a yield (YEtOH) of 0.40 from E. spinosum seaweed. PMID:25649983

  20. Faecal candida and diarrhoea

    PubMed Central

    Forbes, D; Ee, L; Camer-Pesci, P; Ward, P; MURPHY, M

    2001-01-01

    BACKGROUND—Candida species are frequently isolated from stools of children with diarrhoea but are not proven enteropathogens. It is hypothesised that faecal candida causes diarrhoea.
AIMS—To determine the prevalence of faecal candida in childhood diarrhoea and the relation between faecal yeasts and diarrhoea.
METHODS—Comparison of clinical and laboratory data, including quantitative stool culture for yeasts from 107 children hospitalised with diarrhoea and 67 age matched controls without diarrhoea.
RESULTS—Yeast species, predominantly candida, were identified in the stools of 43 children (39%) with diarrhoea and 26 (36%) without diarrhoea. The concentration of candida was positively associated with recent antibiotic use (p = 0.03) and with the presence of another enteric pathogen (p < 0.005), but not with patient age, nutritional status, or duration of diarrhoea.
CONCLUSION—Candida species do not cause childhood diarrhoea in well nourished children.

 PMID:11259233

  1. Genome-Wide Chromatin Immunoprecipitation in Candida albicans and Other Yeasts

    PubMed Central

    Lohse, Matthew B.; Kongsomboonvech, Pisiwat; Madrigal, Maria; Hernday, Aaron D.; Nobile, Clarissa J.

    2016-01-01

    Chromatin immunoprecipitation experiments are critical to investigating the interactions between DNA and a wide range of nuclear proteins within a cell or biological sample. In this chapter we outline an optimized protocol for genome-wide chromatin immunoprecipitation that has been used successfully for several distinct morphological forms of numerous yeast species, and include an optimized method for amplification of chromatin immunoprecipitated DNA samples and hybridization to a high-density oligonucleotide tiling microarray. We also provide detailed suggestions on how to analyze the complex data obtained from these experiments. PMID:26483022

  2. Filamentation protects Candida albicans from amphotericin B-induced programmed cell death via a mechanism involving the yeast metacaspase, MCA1

    PubMed Central

    Laprade, David J.; Brown, Melissa S.; McCarthy, Morgan L.; Ritch, James J.; Austriaco, Nicanor

    2016-01-01

    The budding yeast Candida albicans is one of the most significant fungal pathogens worldwide. It proliferates in two distinct cell types: blastopores and filaments. Only cells that are able to transform from one cell type into the other are virulent in mouse disease models. Programmed cell death is a controlled form of cell suicide that occurs when C. albicans cells are exposed to fungicidal drugs like amphotericin B and caspofungin, and to other stressful conditions. We now provide evidence that suggests that programmed cell death is cell-type specific in yeast: Filamentous C. albicans cells are more resistant to amphotericin B- and caspofungin-induced programmed cell death than their blastospore counterparts. Finally, our genetic data suggests that this phenomenon is mediated by a protective mechanism involving the yeast metacaspase, MCA1. PMID:27683660

  3. Filamentation protects Candida albicans from amphotericin B-induced programmed cell death via a mechanism involving the yeast metacaspase, MCA1

    PubMed Central

    Laprade, David J.; Brown, Melissa S.; McCarthy, Morgan L.; Ritch, James J.; Austriaco, Nicanor

    2016-01-01

    The budding yeast Candida albicans is one of the most significant fungal pathogens worldwide. It proliferates in two distinct cell types: blastopores and filaments. Only cells that are able to transform from one cell type into the other are virulent in mouse disease models. Programmed cell death is a controlled form of cell suicide that occurs when C. albicans cells are exposed to fungicidal drugs like amphotericin B and caspofungin, and to other stressful conditions. We now provide evidence that suggests that programmed cell death is cell-type specific in yeast: Filamentous C. albicans cells are more resistant to amphotericin B- and caspofungin-induced programmed cell death than their blastospore counterparts. Finally, our genetic data suggests that this phenomenon is mediated by a protective mechanism involving the yeast metacaspase, MCA1.

  4. Serological differences between the multiple amine oxidases of yeasts and comparison of the specificities of the purified enzymes from Candida utilis and Pichia pastoris.

    PubMed Central

    Green, J; Haywood, G W; Large, P J

    1983-01-01

    1. Antiserum to purified methylamine oxidase of Candida boidinii formed precipitin lines (with spurs) in double-diffusion tests with crude extracts of methylamine-grown cells of the following yeast species: Candida nagoyaensis, Candida nemodendra, Hansenula minuta, Hansenula polymorpha and Pichia pinus. No cross-reaction was observed with extracts of Candida lipolytica, Candida steatolytica, Candida tropicalis, Candida utilis, Pichia pastoris, Sporobolomyces albo-rubescens, Sporopachydermia cereana or Trigonopsis variabilis. Quantitative enzyme assays enabled the relative titre of antiserum against the various methylamine oxidases to be determined. 2. The amine oxidases from two non-cross-reacting species, C. utilis and P. pastoris, were purified to near homogeneity. 3. The methylamine oxidases, despite their serological non-similarity, showed very similar catalytic properties to methylamine oxidase from C. boidinii. Their heat-stability, pH optima, molecular weights, substrate specificities and sensitivity to inhibitors are reported. 4. The benzylamine oxidases of C. utilis and P. pastoris both oxidized putrescine, and the latter enzyme failed to show any cross-reaction with antibody to C. boidinii methylamine oxidase. Benzylamine oxidase from C. boidinii itself also did not cross-react with antibody to methylamine oxidase. The heat-stability, molecular weights, substrate specificities and sensitivity to inhibitors of the benzylamine/putrescine oxidases are reported. 5. The benzylamine/putrescine oxidase of C. utilis differed only slightly from that of C. boidinii. 6. Benzylamine/putrescine oxidase from P. pastoris differed from the Candida enzymes in heat-stability, subunit molecular weight and substrate specificity. In particular it catalysed the oxidation of the primary amino groups of spermine, spermidine, lysine, ornithine and 1,2-diaminoethane, which are not substrates for either of the Candida benzylamine oxidases that have been purified. 7. Spermine and

  5. Serological differences between the multiple amine oxidases of yeasts and comparison of the specificities of the purified enzymes from Candida utilis and Pichia pastoris.

    PubMed

    Green, J; Haywood, G W; Large, P J

    1983-05-01

    1. Antiserum to purified methylamine oxidase of Candida boidinii formed precipitin lines (with spurs) in double-diffusion tests with crude extracts of methylamine-grown cells of the following yeast species: Candida nagoyaensis, Candida nemodendra, Hansenula minuta, Hansenula polymorpha and Pichia pinus. No cross-reaction was observed with extracts of Candida lipolytica, Candida steatolytica, Candida tropicalis, Candida utilis, Pichia pastoris, Sporobolomyces albo-rubescens, Sporopachydermia cereana or Trigonopsis variabilis. Quantitative enzyme assays enabled the relative titre of antiserum against the various methylamine oxidases to be determined. 2. The amine oxidases from two non-cross-reacting species, C. utilis and P. pastoris, were purified to near homogeneity. 3. The methylamine oxidases, despite their serological non-similarity, showed very similar catalytic properties to methylamine oxidase from C. boidinii. Their heat-stability, pH optima, molecular weights, substrate specificities and sensitivity to inhibitors are reported. 4. The benzylamine oxidases of C. utilis and P. pastoris both oxidized putrescine, and the latter enzyme failed to show any cross-reaction with antibody to C. boidinii methylamine oxidase. Benzylamine oxidase from C. boidinii itself also did not cross-react with antibody to methylamine oxidase. The heat-stability, molecular weights, substrate specificities and sensitivity to inhibitors of the benzylamine/putrescine oxidases are reported. 5. The benzylamine/putrescine oxidase of C. utilis differed only slightly from that of C. boidinii. 6. Benzylamine/putrescine oxidase from P. pastoris differed from the Candida enzymes in heat-stability, subunit molecular weight and substrate specificity. In particular it catalysed the oxidation of the primary amino groups of spermine, spermidine, lysine, ornithine and 1,2-diaminoethane, which are not substrates for either of the Candida benzylamine oxidases that have been purified. 7. Spermine and

  6. Chemical structure of the cell-wall mannan of Candida albicans serotype A and its difference in yeast and hyphal forms

    PubMed Central

    Shibata, Nobuyuki; Suzuki, Akifumi; Kobayashi, Hidemitsu; Okawa, Yoshio

    2007-01-01

    The structure of the cell-wall mannan from the J-1012 (serotype A) strain of the polymorphic yeast Candida albicans was determined by acetolysis under mild conditions followed by HPLC and sequential NMR experiments. The serotype A mannan contained β-1,2-linked mannose residues attached to α-1,3-linked mannose residues and α-1,6-linked branching mannose residues. Using a β-1,2-mannosyltransferase, we synthesized a three-β-1,2-linkage-containing mannoheptaose and used it as a reference oligosaccharide for 1H-NMR assignment. On the basis of the results obtained, we derived an additivity rule for the 1H-NMR chemical shifts of the β-1,2-linked mannose residues. The morphological transformation of Candida cells from the yeast form to the hyphal form induced a significant decrease in the phosphodiesterified acid-labile β-1,2-linked manno-oligosaccharides, whereas the amount of acid-stable β-1,2 linkage-containing side chains did not change. These results suggest that the Candida mannan in candidiasis patients contains β-1,2-linked mannose residues and that they behave as a target of the immune system. PMID:17331070

  7. Biostimulation by methanol enables the methylotrophic yeasts Hansenula polymorpha and Trichosporon sp. to reveal high formaldehyde biodegradation potential as well as to adapt to this toxic pollutant.

    PubMed

    Kaszycki, Paweł; Walski, Tomasz; Hachicho, Nancy; Heipieper, Hermann J

    2013-06-01

    The methylotrophic yeasts Hansenula polymorpha and Trichosporon sp. revealed enhanced biodegradation capability of exogenously applied formaldehyde (Fd) upon biostimulation achieved by the presence of methanol, as compared to glucose. Upon growth on either of the above substrates, the strains proved to produce the activity of glutathione-dependent formaldehyde dehydrogenase-the enzyme known to control the biooxidative step of Fd detoxification. However, in the absence of methanol, the yeasts' tolerance to Fd was decreased, and the elevated sensitivity was especially pronounced for Trichosporon sp. Both strains responded to the methanol and/or Fd treatment by increasing their unsaturation index (UI) at xenobiotic levels below minimal inhibitory concentrations. This indicated that the UI changes effected from the de novo synthesis of (poly) unsaturated fatty acids carried out by viable cells. It is concluded that the yeast cell response to Fd intoxication involves stress reaction at the level of membranes. Fluidization of the lipid bilayer as promoted by methanol is suggested as a significant adaptive mechanism increasing the overall fitness enabling to cope with the formaldehyde xenobiotic via biodegradative pathway of C1-compound metabolism.

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

    PubMed Central

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

    2005-01-01

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

  9. Sporadic Gene Loss After Duplication Is Associated with Functional Divergence of Sirtuin Deacetylases Among Candida Yeast Species

    PubMed Central

    Rupert, Christopher B.; Heltzel, Justin M. H.; Taylor, Derek J.; Rusche, Laura N.

    2016-01-01

    Gene duplication promotes the diversification of protein functions in several ways. Ancestral functions can be partitioned between the paralogs, or a new function can arise in one paralog. These processes are generally viewed as unidirectional. However, paralogous proteins often retain related functions and can substitute for one another. Moreover, in the event of gene loss, the remaining paralog might regain ancestral functions that had been shed. To explore this possibility, we focused on the sirtuin deacetylase SIR2 and its homolog HST1 in the CTG clade of yeasts. HST1 has been consistently retained throughout the clade, whereas SIR2 is only present in a subset of species. These NAD+-dependent deacetylases generate condensed chromatin that represses transcription and stabilizes tandemly repeated sequences. By analyzing phylogenetic trees and gene order, we found that a single duplication of the SIR2/HST1 gene occurred, likely prior to the emergence of the CTG clade. This ancient duplication was followed by at least two independent losses of SIR2. Functional characterization of Sir2 and Hst1 in three species revealed that these proteins have not maintained consistent functions since the duplication. In particular, the rDNA locus is deacetylated by Sir2 in Candida albicans, by Hst1 in C. lusitaniae, and by neither paralog in C. parapsilosis. In addition, the subtelomeres in C. albicans are deacetylated by Sir2 rather than by Hst1, which is orthologous to the sirtuin associated with Saccharomyces cerevisiae subtelomeres. These differences in function support the model that sirtuin deacetylases can regain ancestral functions to compensate for gene loss. PMID:27543294

  10. Multifunctional Centromere Binding Factor 1 Is Essential for Chromosome Segregation in the Human Pathogenic Yeast Candida glabrata

    PubMed Central

    Stoyan, Tanja; Gloeckner, Gernot; Diekmann, Stephan; Carbon, John

    2001-01-01

    The CBF1 (centromere binding factor 1) gene of Candida glabrata was cloned by functional complementation of the methionine biosynthesis defect of a Saccharomyces cerevisiae cbf1 deletion mutant. The C. glabrata-coded protein, CgCbf1, contains a basic-helix-loop-helix leucine zipper domain and has features similar to those of other budding yeast Cbf1 proteins. CgCbf1p binds in vitro to the centromere DNA element I (CDEI) sequence GTCACATG with high affinity (0.9 × 109 M−1). Bandshift experiments revealed a pattern of protein-DNA complexes on CgCEN DNA different from that known for S. cerevisiae. We examined the effect of altering the CDEI binding site on CEN plasmid segregation, using a newly developed colony-sectoring assay. Internal deletion of the CDEI binding site led only to a fivefold increase in rates of plasmid loss, indicating that direct binding of Cbf1p to the centromere DNA is not required for full function. Additional deletion of sequences to the left of CDEI, however, led to a 70-fold increase in plasmid loss rates. Deletion of the CBF1 gene proved to be lethal in C. glabrata. C. glabrata cells containing the CBF1 gene under the influence of a shutdown promoter (tetO-ScHOP) arrested their growth after 5 h of cultivation in the presence of the reactive drug doxycycline. DAPI (4′,6′-diamidino-2-phenylindole) staining of the arrested cells revealed a significant increase in the number of large-budded cells with single nuclei, 2C DNA content, and short spindles, indicating a defect in the G2/M transition of the cell cycle. Thus, we conclude that Cbf1p is required for chromosome segregation in C. glabrata. PMID:11438645

  11. Ultrastructural localization of anionic sites on the surface of yeast, hyphal and germ-tube forming cells of Candida albicans.

    PubMed

    Horisberger, M; Clerc, M F

    1988-08-01

    The cell wall of Candida albicans contains chitin, beta-glucans and phosphorylated mannoproteins, and possesses a fuzzy coat which is thought to play a role in pathogenicity, phagocytosis, and adherence of this dimorphic yeast. Using scanning electron microscopy and the gold method, mannoproteins were detected on the whole surface of blastoconidia including the bud scars, but chitin was absent even after alpha-mannosidase treatment of the cells. The presence of surface beta-(1----6)glucan (but not beta(1----3)glucan) was observed only after extensive alpha-mannosidase and alkaline phosphatase treatments of blastoconidia. Using transmission and scanning electron microscopy, the locations of anionic sites were revealed by polycationic colloidal gold-chitosan complexes on the surface of blastoconidia, germ tubes and hyphae. Anionic sites were dispersed evenly over the surface of blastoconidia bearing bud scars. Depending upon the growth conditions, anionic sites could be detected on emerging buds and young cells. However, bud scars were always free of marking. When germ-tube formation was induced, anionic sites were present at different densities on all cell surfaces, the highest density being observed on cells with bud scars. Anionic sites were detected at a remarkably high density on all hyphal surfaces. An apical concentration of anionic sites was observed on germ tubes and hyphae. The distribution of anionic sites was not modified by endoglucosaminidase treatment of blastoconidia, germ tubes and hyphae. The anionic sites were associated with the fuzzy coat. As the hyphal form is regarded as possessing the greatest invasiveness, it is suggested that anionic sites play an important role in establishing tissue colonization by this human pathogen. PMID:3053174

  12. Fermentation and aerobic metabolism of cellodextrins by yeasts. [Candida wickerhamii; C. guiliermondii; C. molischiana; Debaryomyces polymorphus; Pichia guilliermondii; Clavispora lusitaniae; Kluyveromyces lactis; Brettanomyces claussenii; Rhodotorula minuta; Dekkera intermedia

    SciTech Connect

    Freer, S.N. )

    1991-03-01

    The fermentation and aerobic metabolism of cellodextrins by 14 yeast species or strains was monitored. When grown aerobically, Candida wickerhamii, C. guilliermondii, and C. molischiana metabolized cellodextrins of degree of polymerization 3 to 6. C. wicherhamii and C. molischiana also fermented these substrates, while C. guilliermondii fermented only cellodextrins of degree of polymerization {<=} 3. Debaryomyces polymorphus, Pichia guilliermondii, Clavispora lusitaniae, and one of two strains of Kluyveromyces lactis metabolized glucose, cellobiose, and cellotriose when grown aerobically. These yeasts also fermented these substrates, except for K. lactis, which fermented only glucose and cellobiose. The remaining species/strains tested, K. lactis, Brettanomyces claussenii, Brettanomyces anomalus, Kluyveromyces dobzhanskii, Rhodotorula minuta, and Dekkera intermedia, both fermented and aerobically metabolized glucose and cellobiose. Crude enzyme preparations from all 14 yeast species or strains were tested for ability to hydrolyze cellotriose and cellotretose. Most of the yeasts produced an enzyme(s) capable of hydrolyzing cellotriose. However, with two exceptions, R. minuta and P. guilliermondii, only the yeasts that metabolized cellodextrins of degree of polymerization >3 produced an enzyme(s) that hydrolyzed cellotretose.

  13. Candida albicans cell shaving uncovers new proteins involved in cell wall integrity, yeast to hypha transition, stress response and host-pathogen interaction

    PubMed Central

    Hernáez, María Luisa; Reales-Calderon, Jose Antonio; Solis, Norma V.; Filler, Scott G.; Monteoliva, Lucia; Gil, Concha

    2015-01-01

    The ability to switch from yeast to hyphal growth is essential for virulence in Candida albicans. The cell surface is the initial point of contact between the fungus and the host. In this work, a free-gel proteomic strategy based on tryptic digestion of live yeast and hyphae cells and protein identification using LC-MS/MS methodology was used to identify cell surface proteins. Using this strategy, a total of 943 proteins were identified, of which 438 were in yeast and 928 were in hyphae. Of these proteins, 79 were closely related to the organization and biogenesis of the cell wall, including 28 GPI-anchored proteins, such as Hyr1 and Sod5 which were detected exclusively in hyphae, and Als2 and Sap10which were detected only in yeast. A group of 17 proteins of unknown function were subsequently studied by analysis of the corresponding deletion mutants. We found that four new proteins, Pst3, Tos1, Orf19.3060 and Orf19.5352 are involved in cell wall integrity and in C. albicans’ engulfment by macrophages. Moreover, the putative NADH-ubiquinone-related proteins, Ali1, Mci4, Orf19.287 and Orf19.7590, are also involved in osmotic and oxidative resistance, yeast to hypha transition and the ability to damage and invade oral epithelial cells. PMID:26087349

  14. Evidence for the presence of a high-affinity laminin receptor-like molecule on the surface of Candida albicans yeast cells.

    PubMed Central

    López-Ribot, J L; Casanova, M; Monteagudo, C; Sepúlveda, P; Martínez, J P

    1994-01-01

    Two polypeptides of 37 and 67 kDa that bind laminin were detected in cell wall extracts of Candida albicans blastoconidia. The 37-kDa species, found only in yeast cell wall extracts, cross-reacted with a rabbit polyclonal antibody (PAb 4160) directed towards the carboxyl-terminal laminin-binding domain present in the human 67-kDa high-affinity laminin receptor (67LR) and its 37-kDa precursor (37LRP), whereas another antibody (PAb 4056), directed against internal domains of 67LR and 37LRP, recognized a 37-kDa species in wall extracts from both blastoconidia and germinated blastoconidia. Indirect immunofluorescence with PAb 4160 showed a patchy binding pattern only on yeast cells that represented about 10% of the entire blastoconidia population. Images PMID:8300236

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

    PubMed

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

    2014-07-01

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

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

    PubMed

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

    2014-07-01

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

  17. Activation of the oxidative stress regulator PpYap1 through conserved cysteine residues during methanol metabolism in the yeast Pichia pastoris.

    PubMed

    Yano, Taisuke; Yurimoto, Hiroya; Sakai, Yasuyoshi

    2009-06-01

    The methylotrophic yeast Pichia pastoris can grow on methanol as sole source of carbon and energy. The first reaction in yeast methanol metabolism, catalyzed by an abundant peroxisomal enzyme, alcohol oxidase, generates high levels of H(2)O(2), but the oxidative stress response during methanol metabolism has not been elucidated. In this study, we isolated the Yap1 homolog of P. pastoris (PpYap1) and analyzed the properties of a PpYAP1-disruption strain. The PpYap1 transcription factor is activated after exposure to various reactive agents, and therefore functions as a regulator of the redox system in P. pastoris. We have also identified PpGPX1, the unique glutathione peroxidase-encoding gene in P. pastoris whose expression is induced by PpYap1. PpGpx1, but not the ScTsa1 or SpTpx1 homolog PpTsa1, functions as a H(2)O(2) sensor and activates PpYap1. This study is the first demonstration of a yeast Yap1 family protein activated during conventional metabolism. PMID:19502720

  18. Displaying Lipase B from Candida antarctica in Pichia pastoris Using the Yeast Surface Display Approach: Prospection of a New Anchor and Characterization of the Whole Cell Biocatalyst.

    PubMed

    Moura, Marcelo Victor Holanda; da Silva, Giulia Pontes; Machado, Antônio Carlos de Oliveira; Torres, Fernando Araripe Gonçalves; Freire, Denise Maria Guimarães; Almeida, Rodrigo Volcan

    2015-01-01

    Yeast Surface Display (YSD) is a strategy to anchor proteins on the yeast cell wall which has been employed to increase enzyme stability thus decreasing production costs. Lipase B from Candida antarctica (LipB) is one of the most studied enzymes in the context of industrial biotechnology. This study aimed to assess the biochemical features of this important biocatalyst when immobilized on the cell surface of the methylotrophic yeast Pichia pastoris using the YSD approach. For that purpose, two anchors were tested. The first (Flo9) was identified after a prospection of the P. pastoris genome being related to the family of flocculins similar to Flo1 but significantly smaller. The second is the Protein with Internal Repeats (Pir1) from P. pastoris. An immunolocalization assay showed that both anchor proteins were able to display the reporter protein EGFP in the yeast outer cell wall. LipB was expressed in P. pastoris fused either to Flo9 (FLOLIPB) or Pir1 (PIRLIPB). Both constructions showed hydrolytic activity towards tributyrin (>100 U/mgdcw and >80 U/mgdcw, respectively), optimal hydrolytic activity around 45°C and pH 7.0, higher thermostability at 45°C and stability in organic solvents when compared to a free lipase. PMID:26510006

  19. Displaying Lipase B from Candida antarctica in Pichia pastoris Using the Yeast Surface Display Approach: Prospection of a New Anchor and Characterization of the Whole Cell Biocatalyst

    PubMed Central

    Moura, Marcelo Victor Holanda; da Silva, Giulia Pontes; Machado, Antônio Carlos de Oliveira; Torres, Fernando Araripe Gonçalves; Freire, Denise Maria Guimarães; Almeida, Rodrigo Volcan

    2015-01-01

    Yeast Surface Display (YSD) is a strategy to anchor proteins on the yeast cell wall which has been employed to increase enzyme stability thus decreasing production costs. Lipase B from Candida antarctica (LipB) is one of the most studied enzymes in the context of industrial biotechnology. This study aimed to assess the biochemical features of this important biocatalyst when immobilized on the cell surface of the methylotrophic yeast Pichia pastoris using the YSD approach. For that purpose, two anchors were tested. The first (Flo9) was identified after a prospection of the P. pastoris genome being related to the family of flocculins similar to Flo1 but significantly smaller. The second is the Protein with Internal Repeats (Pir1) from P. pastoris. An immunolocalization assay showed that both anchor proteins were able to display the reporter protein EGFP in the yeast outer cell wall. LipB was expressed in P. pastoris fused either to Flo9 (FLOLIPB) or Pir1 (PIRLIPB). Both constructions showed hydrolytic activity towards tributyrin (>100 U/mgdcw and >80 U/mgdcw, respectively), optimal hydrolytic activity around 45°C and pH 7.0, higher thermostability at 45°C and stability in organic solvents when compared to a free lipase. PMID:26510006

  20. [Demonstration of β-1,2 mannan structures expressed on the cell wall of Candida albicans yeast form but not on the hyphal form by using monoclonal antibodies].

    PubMed

    Aydın, Cevahir; Ataoğlu, Haluk

    2015-01-01

    Candida albicans is a polymorphic fungus that may be observed as both commensal and opportunistic pathogen in humans. As one of the major components of Candida cell wall structure, mannan plays an important role in the fungus-host cell interaction and in virulence. The ability to switch from yeast to hypha form of microorganism is crutial in the development of C.albicans infections. Hyphal form has different antigenic properties compared to yeast form and structural changes occur in the yeast cell wall during transition from yeast to hypha form. Although there are several factors associated with this transition process, sufficient information is not available. The aim of this study was to investigate the change of configuration in mannan structure found in C.albicans cell wall by using monoclonal antibodies. C.albicans (NIHA 207) serotype A strains were used as test strains throughout the study, together with Salmonella choleraesuis 211 and Salmonella infantis as controls with similar cell wall structures to that of C.albicans. Cultures were maintained on YPD-agar medium by incubating at 28°C for yeast forms, and on YPD-broth medium in a shaking incubator at 37°C for 3-4 hours for the growth of hyphal forms. Cells were harvested in the exponential phase, and after being washed, the mannan content from C.albicans were extracted from pellet by heating in 20 mM sodium citrate buffer for 90 minutes at 125°C. Hybridoma technique was used for the production of monoclonal antibodies. After immunizing the Balb/C mice with antigen, the splenocytes were harvested and fusion was performed between spleen cells and F0 myeloma cells. The clones grown in HAT medium were screened for the presence of antibody producing hybrid cells by ELISA method. The antibody isotypes were determined by using a commercial kit (Pierce Biotechnology, ABD). The culture supernatants which contained monoclonal antibodies were collected and purified according to the ammonium sulphate method

  1. Adherence ability of Candida africana: a comparative study with Candida albicans and Candida dubliniensis.

    PubMed

    Romeo, Orazio; De Leo, Filomena; Criseo, Giuseppe

    2011-07-01

    In this study, we compared the adherence ability to human Hela cells and biofilm formation of three closely related Candida yeast. In our experiments, Candida africana showed poor adhesion ability to human Hela cells and the absence of biofilm formation on polyvinyl chloride strips. Conversely, Candida albicans and Candida dubliniensis formed mature biofilms and stable attachment to Hela cells. To our knowledge, this is the first comparative study reporting data on biofilm formation and adherence to human Hela cells by C. africana.

  2. Production of Candida antaractica Lipase B Gene Open Reading Frame using Automated PCR Gene Assembly Protocol on Robotic Workcell & Expression in Ethanologenic Yeast for use as Resin-Bound Biocatalyst in Biodiesel Production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A synthetic Candida antarctica lipase B (CALB) gene open reading frame (ORF) for expression in yeast was produced using an automated PCR assembly and DNA purification protocol on an integrated robotic workcell. The lycotoxin-1 (Lyt-1) C3 variant gene ORF was added in-frame with the CALB ORF to pote...

  3. A Fox2-dependent fatty acid ß-oxidation pathway coexists both in peroxisomes and mitochondria of the ascomycete yeast Candida lusitaniae.

    PubMed

    Gabriel, Frédéric; Accoceberry, Isabelle; Bessoule, Jean-Jacques; Salin, Bénédicte; Lucas-Guérin, Marine; Manon, Stephen; Dementhon, Karine; Noël, Thierry

    2014-01-01

    It is generally admitted that the ascomycete yeasts of the subphylum Saccharomycotina possess a single fatty acid ß-oxidation pathway located exclusively in peroxisomes, and that they lost mitochondrial ß-oxidation early during evolution. In this work, we showed that mutants of the opportunistic pathogenic yeast Candida lusitaniae which lack the multifunctional enzyme Fox2p, a key enzyme of the ß-oxidation pathway, were still able to grow on fatty acids as the sole carbon source, suggesting that C. lusitaniae harbored an alternative pathway for fatty acid catabolism. By assaying 14Cα-palmitoyl-CoA consumption, we demonstrated that fatty acid catabolism takes place in both peroxisomal and mitochondrial subcellular fractions. We then observed that a fox2Δ null mutant was unable to catabolize fatty acids in the mitochondrial fraction, thus indicating that the mitochondrial pathway was Fox2p-dependent. This finding was confirmed by the immunodetection of Fox2p in protein extracts obtained from purified peroxisomal and mitochondrial fractions. Finally, immunoelectron microscopy provided evidence that Fox2p was localized in both peroxisomes and mitochondria. This work constitutes the first demonstration of the existence of a Fox2p-dependent mitochondrial β-oxidation pathway in an ascomycetous yeast, C. lusitaniae. It also points to the existence of an alternative fatty acid catabolism pathway, probably located in peroxisomes, and functioning in a Fox2p-independent manner. PMID:25486052

  4. Multicenter study of epidemiological cutoff values and detection of resistance in Candida spp. to anidulafungin, caspofungin, and micafungin using the Sensititre YeastOne colorimetric method.

    PubMed

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

    2015-11-01

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

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

    PubMed Central

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

    2015-01-01

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

  6. Results from the ARTEMIS DISK Global Antifungal Surveillance Study, 1997 to 2005: an 8.5-Year Analysis of Susceptibilities of Candida Species and Other Yeast Species to Fluconazole and Voriconazole Determined by CLSI Standardized Disk Diffusion Testing▿

    PubMed Central

    Pfaller, M. A.; Diekema, D. J.; Gibbs, D. L.; Newell, V. A.; Meis, J. F.; Gould, I. M.; Fu, W.; Colombo, A. L.; Rodriguez-Noriega, E.

    2007-01-01

    Fluconazole in vitro susceptibility test results for 205,329 yeasts were collected from 134 study sites in 40 countries from June 1997 through December 2005. Data were collected for 147,776 yeast isolates tested with voriconazole from 2001 through 2005. All investigators tested clinical yeast isolates by the CLSI M44-A disk diffusion method. Test plates were automatically read and results recorded with a BIOMIC image analysis system. Species, drug, zone diameter, susceptibility category, and quality control results were collected quarterly. Duplicate (same patient, same species, and same susceptible-resistant biotype profile during any 7-day period) and uncontrolled test results were not analyzed. Overall, 90.1% of all Candida isolates tested were susceptible (S) to fluconazole; however, 10 of the 22 species identified exhibited decreased susceptibility (<75% S) on the order of that seen with the resistant (R) species C. glabrata and C. krusei. Among 137,487 isolates of Candida spp. tested against voriconazole, 94.8% were S and 3.1% were R. Less than 30% of fluconazole-resistant isolates of C. albicans, C. glabrata, C. tropicalis, and C. rugosa remained S to voriconazole. The non-Candida yeasts (8,821 isolates) were generally less susceptible to fluconazole than Candida spp. but, aside from Rhodotorula spp., remained susceptible to voriconazole. This survey demonstrates the broad spectrum of these azoles against the most common opportunistic yeast pathogens but identifies several less common yeast species with decreased susceptibility to antifungal agents. These organisms may pose a future threat to optimal antifungal therapy and emphasize the importance of prompt and accurate species identification. PMID:17442797

  7. [Autochthonous yeasts isolated in Tenerife wines and their influence on ethyl acetate and higher alcohol concentrations analyzed by gas chromatography].

    PubMed

    Salvadores, M P; Díaz, M E; Cardell, E

    1993-12-01

    A taxonomic study of yeasts present on Tenerife wines, (Tacoronte-Acentejo Specific Denomination) has been carried out. Nine species of the genera: Saccharomyces, Torulaspora, Brettanomyces, Kluyveromyces, Debaryomyces, Saccharomycodes, Hansenula, Pichia and Candida have been isolated. Parallely we analysed volatile compounds of the wines such as ethyl acetate, methanol, isobutanol and amylic alcohols by gas chromatography. Appreciable quantities of ethyl acetate were detected due to the low fermentative power of species such as Candida glabrata and Debaryomyces hansenii. The greatest concentration of amylic alcohols were found in wines containing yeast with high alcohol producing power like Saccharomyces cerevisiae.

  8. Berberine Antifungal Activity in Fluconazole-Resistant Pathogenic Yeasts: Action Mechanism Evaluated by Flow Cytometry and Biofilm Growth Inhibition in Candida spp.

    PubMed

    da Silva, Anderson Ramos; de Andrade Neto, João Batista; da Silva, Cecília Rocha; Campos, Rosana de Sousa; Costa Silva, Rose Anny; Freitas, Daniel Domingues; do Nascimento, Francisca Bruna Stefany Aires; de Andrade, Larissa Nara Dantas; Sampaio, Letícia Serpa; Grangeiro, Thalles Barbosa; Magalhães, Hemerson Iury Ferreira; Cavalcanti, Bruno Coêlho; de Moraes, Manoel Odorico; Nobre Júnior, Hélio Vitoriano

    2016-06-01

    The incidence of fungal infections and, in particular, the incidence of fungal antibiotic resistance, which is associated with biofilm formation, have significantly increased, contributing to morbidity and mortality. Thus, new therapeutic strategies need to be developed. In this context, natural products have emerged as a major source of possible antifungal agents. Berberine is a protoberberine-type isoquinoline alkaloid isolated from the roots, rhizomes, and stem bark of natural herbs, such as Berberis aquifolium, Berberis vulgaris, Berberis aristata, and Hydrastis canadensis, and of Phellodendron amurense Berberine has been proven to have broad antibacterial and antifungal activity. In the present study, the potential antifungal effect of berberine against fluconazole-resistant Candida and Cryptococcus neoformans strains, as well as against the biofilm form of Candida spp., was assessed. The antifungal effect of berberine was determined by a broth microdilution method (the M27-A3 method of the Clinical and Laboratory Standards Institute) and flow cytometry techniques, in which the probable mechanism of action of the compound was also assessed. For biofilm assessment, a colorimetric 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay was used to determine the susceptibility of sessile cells. The isolates used in the study belonged to the Laboratory of Bioprospection and Experiments in Yeast (LABEL) of the Federal University of Ceará. After 24 and 72 h, fluconazole-resistant Candida and Cryptococcus neoformans strains showed berberine MICs equal to 8 μg/ml and 16 μg/ml, respectively. Cytometric analysis showed that treatment with berberine caused alterations to the integrity of the plasma and mitochondrial membranes and DNA damage, which led to cell death, probably by apoptosis. Assessment of biofilm-forming isolates after treatment showed statistically significant reductions in biofilm cell activity (P < 0.001). PMID:27021328

  9. Berberine Antifungal Activity in Fluconazole-Resistant Pathogenic Yeasts: Action Mechanism Evaluated by Flow Cytometry and Biofilm Growth Inhibition in Candida spp.

    PubMed Central

    da Silva, Anderson Ramos; de Andrade Neto, João Batista; da Silva, Cecília Rocha; Campos, Rosana de Sousa; Costa Silva, Rose Anny; Freitas, Daniel Domingues; do Nascimento, Francisca Bruna Stefany Aires; de Andrade, Larissa Nara Dantas; Sampaio, Letícia Serpa; Grangeiro, Thalles Barbosa; Magalhães, Hemerson Iury Ferreira; Cavalcanti, Bruno Coêlho; de Moraes, Manoel Odorico

    2016-01-01

    The incidence of fungal infections and, in particular, the incidence of fungal antibiotic resistance, which is associated with biofilm formation, have significantly increased, contributing to morbidity and mortality. Thus, new therapeutic strategies need to be developed. In this context, natural products have emerged as a major source of possible antifungal agents. Berberine is a protoberberine-type isoquinoline alkaloid isolated from the roots, rhizomes, and stem bark of natural herbs, such as Berberis aquifolium, Berberis vulgaris, Berberis aristata, and Hydrastis canadensis, and of Phellodendron amurense. Berberine has been proven to have broad antibacterial and antifungal activity. In the present study, the potential antifungal effect of berberine against fluconazole-resistant Candida and Cryptococcus neoformans strains, as well as against the biofilm form of Candida spp., was assessed. The antifungal effect of berberine was determined by a broth microdilution method (the M27-A3 method of the Clinical and Laboratory Standards Institute) and flow cytometry techniques, in which the probable mechanism of action of the compound was also assessed. For biofilm assessment, a colorimetric 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay was used to determine the susceptibility of sessile cells. The isolates used in the study belonged to the Laboratory of Bioprospection and Experiments in Yeast (LABEL) of the Federal University of Ceará. After 24 and 72 h, fluconazole-resistant Candida and Cryptococcus neoformans strains showed berberine MICs equal to 8 μg/ml and 16 μg/ml, respectively. Cytometric analysis showed that treatment with berberine caused alterations to the integrity of the plasma and mitochondrial membranes and DNA damage, which led to cell death, probably by apoptosis. Assessment of biofilm-forming isolates after treatment showed statistically significant reductions in biofilm cell activity (P < 0.001). PMID:27021328

  10. Effect of scenedesmus acuminatus green algae extracts on the development of Candida lipolytic yeast in gas condensate-containing media

    NASA Technical Reports Server (NTRS)

    Bilmes, B. I.; Kasymova, G. A.; Runov, V. I.; Karavayeva, N. N.

    1980-01-01

    Data are given of a comparative study of the growth and development as well as the characteristics of the biomass of the C. Lipolytica yeast according to the content of raw protein, protein, lipids, vitamins in the B group, and residual hydrocarbons during growth in media with de-aromatized gas-condensate FNZ as the carbon source with aqueous and alcohol extracts of S. acuminatus as the biostimulants. It is shown that the decoction and aqueous extract of green algae has the most intensive stimulating effect on the yeast growth. When a decoction of algae is added to the medium, the content of residual hydrocarbons in the biomass of C. lipolytica yeast is reduced by 4%; the quantity of protein, lipids, thamine and inositol with replacement of the yeast autolysate by the decoction of algae is altered little.

  11. Silica sol-gel encapsulated methylotrophic yeast as filling of biofilters for the removal of methanol from industrial wastewater.

    PubMed

    Kamanina, Olga A; Lavrova, Daria G; Arlyapov, Viacheslav A; Alferov, Valeriy A; Ponamoreva, Olga N

    2016-10-01

    This research suggests the use of new hybrid biomaterials based on methylotrophic yeast cells covered by an alkyl-modified silica shell as biocatalysts. The hybrid biomaterials are produced by sol-gel chemistry from silane precursors. The shell protects microbial cells from harmful effects of acidic environment. Potential use of the hybrid biomaterials based on methylotrophic yeast Ogataea polymorpha VKM Y-2559 encapsulated into alkyl-modified silica matrix for biofilters is represented for the first time. Organo-silica shells covering yeast cells effectively protect them from exposure to harmful factors, including extreme values of pH. The biofilter based on the organic silica matrix encapsulated in the methylotrophic yeast Ogataea polymorpha BKM Y-2559 has an oxidizing power of 3 times more than the capacity of the aeration tanks used at the chemical plants during methyl alcohol production. This may lead to the development of new and effective industrial wastewater treatment technologies. PMID:27542749

  12. Silica sol-gel encapsulated methylotrophic yeast as filling of biofilters for the removal of methanol from industrial wastewater.

    PubMed

    Kamanina, Olga A; Lavrova, Daria G; Arlyapov, Viacheslav A; Alferov, Valeriy A; Ponamoreva, Olga N

    2016-10-01

    This research suggests the use of new hybrid biomaterials based on methylotrophic yeast cells covered by an alkyl-modified silica shell as biocatalysts. The hybrid biomaterials are produced by sol-gel chemistry from silane precursors. The shell protects microbial cells from harmful effects of acidic environment. Potential use of the hybrid biomaterials based on methylotrophic yeast Ogataea polymorpha VKM Y-2559 encapsulated into alkyl-modified silica matrix for biofilters is represented for the first time. Organo-silica shells covering yeast cells effectively protect them from exposure to harmful factors, including extreme values of pH. The biofilter based on the organic silica matrix encapsulated in the methylotrophic yeast Ogataea polymorpha BKM Y-2559 has an oxidizing power of 3 times more than the capacity of the aeration tanks used at the chemical plants during methyl alcohol production. This may lead to the development of new and effective industrial wastewater treatment technologies.

  13. 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.

  14. Pretreatment of the yeast antagonist, Candida oleophila with glycine betaine increases oxidative stress tolerance in the microenvironment of apple wounds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In response to wounding, harvested fruit tissues of apple and citrus exhibit the production of reactive oxygen species (ROS). ROS production is greater when yeast antagonists used as biocontrol agents are applied in the wounds. These phenomena result in an oxidative stress environment for the yeas...

  15. Exploring ecological modelling to investigate factors governing the colonization success in nosocomial environment of Candida albicans and other pathogenic yeasts

    PubMed Central

    Corte, Laura; Roscini, Luca; Colabella, Claudia; Tascini, Carlo; Leonildi, Alessandro; Sozio, Emanuela; Menichetti, Francesco; Merelli, Maria; Scarparo, Claudio; Meyer, Wieland; Cardinali, Gianluigi; Bassetti, Matteo

    2016-01-01

    Two hundred seventy seven strains from eleven opportunistic species of the genus Candida, isolated from two Italian hospitals, were identified and analyzed for their ability to form biofilm in laboratory conditions. The majority of Candida albicans strains formed biofilm while among the NCAC species there were different level of biofilm forming ability, in accordance with the current literature. The relation between the variables considered, i.e. the departments and the hospitals or the species and their ability to form biofilm, was tested with the assessment of the probability associated to each combination. Species and biofilm forming ability appeared to be distributed almost randomly, although some combinations suggest a potential preference of some species or of biofilm forming strains for specific wards. On the contrary, the relation between biofilm formation and species isolation frequency was highly significant (R2 around 0.98). Interestingly, the regression analyses carried out on the data of the two hospitals separately were rather different and the analysis on the data merged together gave a much lower correlation. These findings suggest that, harsh environments shape the composition of microbial species significantly and that each environment should be considered per se to avoid less significant statistical treatments. PMID:27246511

  16. Characterization of the interactions between human high-molecular-mass kininogen and cell wall proteins of pathogenic yeasts Candida tropicalis.

    PubMed

    Karkowska-Kuleta, Justyna; Zajac, Dorota; Bras, Grazyna; Bochenska, Oliwia; Seweryn, Karolina; Kedracka-Krok, Sylwia; Jankowska, Urszula; Rapala-Kozik, Maria; Kozik, Andrzej

    2016-01-01

    Candida tropicalis is one of the most frequent causes of serious disseminated candidiasis in human patients infected by non-albicans Candida species, but still relatively little is known about its virulence mechanisms. In our current study, the interactions between the cell surface of this species and a multifunctional human protein - high-molecular-mass kininogen (HK), an important component of the plasma contact system involved in the development of the inflammatory state - were characterized at the molecular level. The quick release of biologically active kinins from candidal cell wall-adsorbed HK was presented and the HK-binding ability was assigned to several cell wall-associated proteins. The predicted hyphally regulated cell wall protein (Hyr) and some housekeeping enzymes exposed at the cell surface (known as "moonlighting proteins") were found to be the major HK binders. Accordingly, after purification of selected proteins, the dissociation constants of the complexes of HK with Hyr, enolase, and phosphoglycerate mutase were determined using surface plasmon resonance measurements, yielding the values of 2.20 × 10(-7) M, 1.42 × 10(-7) M, and 5.81 × 10(-7) M, respectively. Therefore, in this work, for the first time, the interactions between C. tropicalis cell wall proteins and HK were characterized in molecular terms. Our findings may be useful for designing more effective prevention and treatment approaches against infections caused by this dangerous fungal pathogen. PMID:27474405

  17. In Vitro Anti-Candida Activity of Zataria multiflora Boiss

    PubMed Central

    Dabbagh, Muhammad Ali; Fouladi, Zahra

    2007-01-01

    Zataria multiflora Boiss known as Avishan Shirazi (in Iran) is one of the valuable Iranian medicinal plants. The aim of study was to evaluate anti-Candida activity of Z. multiflora against different species of Candida in vitro. Anti-Candida activity of the aqueous, ethanolic and methanolic maceration extract of the aerial parts of Z. multiflora Boiss was studied in vitro. Anti-Candida activity against Candida species was done using serial dilutions of extracts in Sabouraud's dextrose agar. Minimal inhibitory concentration (MIC) of the methanolic and ethanolic extracts was 70.7 and 127 mg l−1, respectively. Aqueous extract showed no remarkable activity against Candida species. We conclude that methanolic extract of the aerial parts of Z. multiflora Boiss has more anti-Candida effect at 70.7 mg l−1 compared to ethanolic extract 127 mg l−1. In addition, the isolates of Candida parapsilosis were more susceptible to methanolic extract than other tested species. PMID:17965766

  18. High-frequency transformation of a methylotrophic yeast, Candida boidinii, with autonomously replicating plasmids which are also functional in Saccharomyces cerevisiae.

    PubMed

    Sakai, Y; Goh, T K; Tani, Y

    1993-06-01

    We have developed a transformation system which uses autonomous replicating plasmids for a methylotrophic yeast, Candida boidinii. Two autonomous replication sequences, CARS1 and CARS2, were newly cloned from the genome of C. boidinii. Plasmids having both a CARS fragment and the C. boidinii URA3 gene transformed C. boidinii ura3 cells to Ura+ phenotype at frequencies of up to 10(4) CFU/micrograms of DNA. From Southern blot analysis, CARS plasmids seemed to exist in polymeric forms as well as in monomeric forms in C. boidinii cells. The C. boidinii URA3 gene was overexpressed in C. boidinii on these CARS vectors. CARS1 and CARS2 were found to function as an autonomous replicating element in Saccharomyces cerevisiae as well. Different portions of the CARS1 sequence were needed for autonomous replicating activity in C. boidinii and S. cerevisiae. C. boidinii could also be transformed with vectors harboring a CARS fragment and the S. cerevisiae URA3 gene.

  19. High-frequency transformation of a methylotrophic yeast, Candida boidinii, with autonomously replicating plasmids which are also functional in Saccharomyces cerevisiae.

    PubMed

    Sakai, Y; Goh, T K; Tani, Y

    1993-06-01

    We have developed a transformation system which uses autonomous replicating plasmids for a methylotrophic yeast, Candida boidinii. Two autonomous replication sequences, CARS1 and CARS2, were newly cloned from the genome of C. boidinii. Plasmids having both a CARS fragment and the C. boidinii URA3 gene transformed C. boidinii ura3 cells to Ura+ phenotype at frequencies of up to 10(4) CFU/micrograms of DNA. From Southern blot analysis, CARS plasmids seemed to exist in polymeric forms as well as in monomeric forms in C. boidinii cells. The C. boidinii URA3 gene was overexpressed in C. boidinii on these CARS vectors. CARS1 and CARS2 were found to function as an autonomous replicating element in Saccharomyces cerevisiae as well. Different portions of the CARS1 sequence were needed for autonomous replicating activity in C. boidinii and S. cerevisiae. C. boidinii could also be transformed with vectors harboring a CARS fragment and the S. cerevisiae URA3 gene. PMID:8501059

  20. High level production of thermostable alpha-amylase from Sulfolobus solfataricus in high-cell density culture of the food yeast Candida utilis.

    PubMed

    Miura, Y; Kettoku, M; Kato, M; Kobayashi, K; Kondo, K

    1999-08-01

    The alpha-amylase from Sulfolobus solfataricus has the commercially important ability to hydrolyze glycosyltrehalose and can be used for the production of trehalose from soluble starch. We have produced this enzyme in the food yeast Candida utilis at extremely high levels. Because the S. solfataricus gene was previously shown to be very poorly expressed, the gene was resynthesized based on codons preferentially found in the highly expressed C. utilis glyceraldehyde-3-phosphate dehydrogenase (GAP) gene. Expression of this synthetic gene under the control of the GAP promoter yielded biologically active alpha-amylase, accounting for more than 50% of the soluble protein. Comparison of the expression levels of various chimeric constructs of the synthetic and native genes indicated that the production level of the alpha-amylase was improved more than 2x10(4)-fold by substituting the native gene with the synthesized one. Northern analysis revealed the formation of short mRNAs in transformants with constructs containing native gene fragments, suggesting that premature termination of the transcripts is responsible for the low production level. The alpha-amylase-producing C. utilis cells were grown up to 92 grams dry cell weight per liter in a synthetic medium, yielding 12.3 g/l alpha-amylase which accounts for up to 27% of total cell proteins.

  1. Effects of lignin-derived phenolic compounds on xylitol production and key enzyme activities by a xylose utilizing yeast Candida athensensis SB18.

    PubMed

    Zhang, Jinming; Geng, Anli; Yao, Chuanyi; Lu, Yinghua; Li, Qingbiao

    2012-10-01

    Candida athensensis SB18 is potential xylitol producing yeast isolated in Singapore. It has excellent xylose tolerance and is able to produce xylitol in high titer and yield. However, by-products, such as phenolic compounds, derived in lignocellulosic biomass hydrolysate might negatively influence the performance of this strain for xylitol production. In this work, four potential phenolic inhibitors, such as vanillin, syringaldehyde, 4-hydroxybenzaldehyde and phenol, were evaluated for their inhibitory effects on xylitol production by C. athensensis SB18. Phenol was shown to be the most toxic molecule on this microorganism followed by syringaldehyde. Vanillin and 4-hydroxylbenzaldehyde was less toxic than phenol and syringaldehyde, with vanillin being the least toxic. Inhibition was insignificant when the total content of inhibitors was below 1.0 g/L. The presence of phenolic compounds affected the activity of xylose reductase, however not on that of xylitol dehydrogenase. C. athensensis SB18 is therefore a potential xylitol producer from hemicellulosic hydrolysate due to its assimilation of such phenolic inhibitors.

  2. Aerobic decolorization and degradation of azo dyes by growing cells of a newly isolated yeast Candida tropicalis TL-F1.

    PubMed

    Tan, Liang; Ning, Shuxiang; Zhang, Xuwang; Shi, Shengnan

    2013-06-01

    The aim of this work was to investigate the decolorization and degradation of azo dyes by growing cells of a new yeast strain TL-F1 which was isolated from the sea mud. Strain TL-F1 was identified as Candida tropicalis on the basis of 28S rDNA analysis. Various azo dyes (20mg/L) were efficiently decolorized through aerobic degradation. Meantime, the effects of different parameters on both decolorization of Acid Brilliant Scarlet GR and growth of strain TL-F1 were investigated. Furthermore, possible degradation pathway of the dye GR was proposed through analysis of metabolic products using UV-Vis spectroscopy and HPLC-MS methods. As far as it is known, it is the first systematic research on a C. tropicalis strain which is capable of efficiently decolorizing various azo dyes under aerobic condition. This work provides a potentially useful microbial strain TL-F1 for treatment of azo dye contaminated wastewater.

  3. Methanol Expression Regulator 1 (Mxr1p) Is Essential for the Utilization of Amino Acids as the Sole Source of Carbon by the Methylotrophic Yeast, Pichia pastoris.

    PubMed

    Sahu, Umakant; Rangarajan, Pundi N

    2016-09-23

    Unlike Saccharomyces cerevisiae, the methylotrophic yeast Pichia pastoris can assimilate amino acids as the sole source of carbon and nitrogen. It can grow in media containing yeast extract and peptone (YP), yeast nitrogen base (YNB) + glutamate (YNB + Glu), or YNB + aspartate (YNB + Asp). Methanol expression regulator 1 (Mxr1p), a zinc finger transcription factor, is essential for growth in these media. Mxr1p regulates the expression of several genes involved in the utilization of amino acids as the sole source of carbon and nitrogen. These include the following: (i) GDH2 encoding NAD-dependent glutamate dehydrogenase; (ii) AAT1 and AAT2 encoding mitochondrial and cytosolic aspartate aminotransferases, respectively; (iii) MDH1 and MDH2 encoding mitochondrial and cytosolic malate dehydrogenases, respectively; and (iv) GLN1 encoding glutamine synthetase. Synthesis of all these enzymes is regulated by Mxr1p at the level of transcription except GDH2, whose synthesis is regulated at the level of translation. Mxr1p activates the transcription of AAT1, AAT2, and GLN1 in cells cultured in YP as well as in YNB + Glu media, whereas transcription of MDH1 and MDH2 is activated in cells cultured in YNB + Glu but not in YP. A truncated Mxr1p composed of 400 N-terminal amino acids activates transcription of target genes in cells cultured in YP but not in YNB + Glu. Mxr1p binds to Mxr1p response elements present in the promoters of AAT2, MDH2, and GLN1 We conclude that Mxr1p is essential for utilization of amino acids as the sole source of carbon and nitrogen, and it is a global regulator of multiple metabolic pathways in P. pastoris. PMID:27519409

  4. Methanol Expression Regulator 1 (Mxr1p) Is Essential for the Utilization of Amino Acids as the Sole Source of Carbon by the Methylotrophic Yeast, Pichia pastoris.

    PubMed

    Sahu, Umakant; Rangarajan, Pundi N

    2016-09-23

    Unlike Saccharomyces cerevisiae, the methylotrophic yeast Pichia pastoris can assimilate amino acids as the sole source of carbon and nitrogen. It can grow in media containing yeast extract and peptone (YP), yeast nitrogen base (YNB) + glutamate (YNB + Glu), or YNB + aspartate (YNB + Asp). Methanol expression regulator 1 (Mxr1p), a zinc finger transcription factor, is essential for growth in these media. Mxr1p regulates the expression of several genes involved in the utilization of amino acids as the sole source of carbon and nitrogen. These include the following: (i) GDH2 encoding NAD-dependent glutamate dehydrogenase; (ii) AAT1 and AAT2 encoding mitochondrial and cytosolic aspartate aminotransferases, respectively; (iii) MDH1 and MDH2 encoding mitochondrial and cytosolic malate dehydrogenases, respectively; and (iv) GLN1 encoding glutamine synthetase. Synthesis of all these enzymes is regulated by Mxr1p at the level of transcription except GDH2, whose synthesis is regulated at the level of translation. Mxr1p activates the transcription of AAT1, AAT2, and GLN1 in cells cultured in YP as well as in YNB + Glu media, whereas transcription of MDH1 and MDH2 is activated in cells cultured in YNB + Glu but not in YP. A truncated Mxr1p composed of 400 N-terminal amino acids activates transcription of target genes in cells cultured in YP but not in YNB + Glu. Mxr1p binds to Mxr1p response elements present in the promoters of AAT2, MDH2, and GLN1 We conclude that Mxr1p is essential for utilization of amino acids as the sole source of carbon and nitrogen, and it is a global regulator of multiple metabolic pathways in P. pastoris.

  5. [Effects of combined addition of atovaquone and lithium on the in vitro cell growth of the pathogenic yeast Candida albicans].

    PubMed

    Minagawa, Nobuko; Uehara, Mariko; Seki, Shiori; Nitta, Ayumi; Kogawara, Kento

    2010-02-01

    Atovaquone, an analog of ubiquinone, binds tightly to the ubiquinol oxidation site (Qo site) of parasite cytochrome bc(1) complex to inhibit electron transport at concentrations far lower than those at which the mammalian system is affected. The mode of action is thought similar to that of myxothiazol. To treat Pneumocystis jirovecii and Plasmodium falciparum infections, atovaquone has been used worldwide whereas it is unapproved in Japan. Since the pathogenic Candida species fungi seem resistant to atovaquone, this drug is not clinically available for candidosis, particularly deep mycosis. We examined the effects of atovaquone on cellular respiration and in vitro growth of C. albicans to explore a new therapeutic possibility for fungal infections. Atovaquone strongly inhibited glucose-dependent cellular respiration similarly to antimycin A, stigmatellin, and myxothiazol, specific bc(1) complex inhibitors. However, atovaquone suppressed glucose-dependent cell growth to a much lesser extent versus the comparator agents. When added alone, lithium exerted slight growth inhibition. The combined addition of lithium with atovaquone showed a significant increase in inhibition of growth. Although the way lithium acts synergistically with atovaquone remains to be elucidated, our results suggest a new therapeutic possibility of this combination for the treatment of candidosis.

  6. N-Acetylglucosamine-Induced Cell Death in Candida albicans and Its Implications for Adaptive Mechanisms of Nutrient Sensing in Yeasts

    PubMed Central

    Du, Han; Guan, Guobo; Li, Xiaoling; Gulati, Megha; Tao, Li; Cao, Chengjun; Johnson, Alexander D.; Nobile, Clarissa J.

    2015-01-01

    ABSTRACT Single-celled organisms have different strategies to sense and utilize nutrients in their ever-changing environments. The opportunistic fungal pathogen Candida albicans is a common member of the human microbiota, especially that of the gastrointestinal (GI) tract. An important question concerns how C. albicans gained a competitive advantage over other microbes to become a successful commensal and opportunistic pathogen. Here, we report that C. albicans uses N-acetylglucosamine (GlcNAc), an abundant carbon source present in the GI tract, as a signal for nutrient availability. When placed in water, C. albicans cells normally enter the G0 phase and remain viable for weeks. However, they quickly lose viability when cultured in water containing only GlcNAc. We term this phenomenon GlcNAc-induced cell death (GICD). GlcNAc triggers the upregulation of ribosomal biogenesis genes, alterations of mitochondrial metabolism, and the accumulation of reactive oxygen species (ROS), followed by rapid cell death via both apoptotic and necrotic mechanisms. Multiple pathways, including the conserved cyclic AMP (cAMP) signaling and GlcNAc catabolic pathways, are involved in GICD. GlcNAc acts as a signaling molecule to regulate multiple cellular programs in a coordinated manner and therefore maximizes the efficiency of nutrient use. This adaptive behavior allows C. albicans’ more efficient colonization of the gut. PMID:26350972

  7. Metabolic flux analysis model for optimizing xylose conversion into ethanol by the natural C5-fermenting yeast Candida shehatae.

    PubMed

    Bideaux, Carine; Montheard, Julie; Cameleyre, Xavier; Molina-Jouve, Carole; Alfenore, Sandrine

    2016-02-01

    A metabolic flux analysis (MFA) model was developed to optimize the xylose conversion into ethanol using Candida shehatae strain. This metabolic model was compartmented and constructed with xylose as carbon substrate integrating the enzymatic duality of the first step of xylose degradation via an algebraic coefficient. The model included the pentose phosphate pathway, glycolysis, synthesis of major metabolites like ethanol, acetic acid and glycerol, the tricarboxylic acid cycle as well as the respiratory chain, the cofactor balance, and the maintenance. The biomass composition and thus production were integrated considering the major biochemical synthesis reactions from monomers to each constitutive macromolecule (i.e., proteins, lipids, polysaccharides, nucleic acids). The construction of the model resulted into a 122-linear equation system to be resolved. A first experiment allowed was to verify the accuracy of the model by comparing calculated and experimental data. The metabolic model was utilized to determine the theoretical yield taking into account oxido-reductive balance and to optimize ethanol production. The maximal theoretical yield was calculated at 0.62 Cmolethanol/Cmolxylose for an oxygen requirement of 0.33 moloxygen/molxylose linked to the cofactors of the xylose reductase. Cultivations in chemostat mode allowed the fine tuning of both xylose and oxygen uptakes and showed that lower was the oxygen/xylose ratio, higher was the ethanol production yield. The best experimental ethanol production yield (0.51 Cmolethanol/Cmolxylose) was obtained for an oxygen supply of 0.47 moloxygen/molxylose.

  8. Epidemiological Cutoff Values for Fluconazole, Itraconazole, Posaconazole, and Voriconazole for Six Candida Species as Determined by the Colorimetric Sensititre YeastOne Method

    PubMed Central

    Pemán, Javier; Iñiguez, Carmen; Hervás, David; Lopez-Hontangas, Jose L.; Pina-Vaz, Cidalia; Camarena, Juan J.; Campos-Herrero, Isolina; García-García, Inmaculada; García-Tapia, Ana M.; Guna, Remedios; Merino, Paloma; Pérez del Molino, Luisa; Rubio, Carmen; Suárez, Anabel

    2013-01-01

    In the absence of clinical breakpoints (CBP), epidemiological cutoff values (ECVs) are useful to separate wild-type (WT) isolates (without mechanisms of resistance) from non-WT isolates (those that can harbor some resistance mechanisms), which is the goal of susceptibility tests. Sensititre YeastOne (SYO) is a widely used method to determine susceptibility of Candida spp. to antifungal agents. The CLSI CBP have been established, but not for the SYO method. The ECVs for four azoles, obtained using MIC distributions determined by the SYO method, were calculated via five methods (three statistical methods and based on the MIC50 and modal MIC). Respectively, the median ECVs (in mg/liter) of the five methods for fluconazole, itraconazole, posaconazole, and voriconazole (in parentheses: the percentage of isolates inhibited by MICs equal to or less than the ECVs; the number of isolates tested) were as follows: 2 (94.4%; 944), 0.5 (96.7%; 942), 0.25 (97.6%; 673), and 0.06 (96.7%; 849) for Candida albicans; 4 (86.1%; 642), 0.5 (99.4%; 642), 0.12 (93.9%; 392), and 0.06 (86.9%; 559) for C. parapsilosis; 8 (94.9%; 175), 1 (93.7%; 175), 2 (93.6%; 125), and 0.25 (90.4%; 167) for C. tropicalis; 128 (98.6%; 212), 4 (95.8%; 212), 4 (96.0%; 173), and 2 (98.5; 205) for C. glabrata; 256 (100%; 53), 1 (98.1%; 53), 1 (100%; 33), and 1 (97.9%; 48) for C. krusei; 4 (89.2%; 93), 0.5 (100%; 93), 0.25 (100%; 33), and 0.06 (87.7%; 73) for C. orthopsilosis. All methods included ≥94% of isolates and yielded similar ECVs (within 1 dilution). These ECVs would be suitable for monitoring emergence of isolates with reduced susceptibility by using the SYO method. PMID:23761155

  9. New and emerging yeast pathogens.

    PubMed Central

    Hazen, K C

    1995-01-01

    The most common yeast species that act as agents of human disease are Candida albicans, Candida tropicalis, Candida glabrata, Candida parapsilosis, and Cryptococcus neoformans. The incidence of infections by other yeasts has increased during the past decade. The most evident emerging pathogens are Malassezia furfur, Trichosporon beigelii, Rhodotorula species, Hansenula anomala, Candida lusitaniae, and Candida krusei. Organisms once considered environmental contaminants or only industrially important, such as Candida utilis and Candida lipolytica, have now been implicated as agents of fungemia, onychomycosis, and systemic disease. The unusual yeasts primarily infect immunocompromised patients, newborns, and the elderly. The role of central venous catheter removal and antifungal therapy in patient management is controversial. The antibiograms of the unusual yeasts range from resistant to the most recent azoles and amphotericin B to highly susceptible to all antifungal agents. Current routine methods for yeast identification may be insufficient to identify the unusual yeasts within 2 days after isolation. The recognition of unusual yeasts as agents of sometimes life-threatening infection and their unpredictable antifungal susceptibilities increase the burden on the clinical mycology laboratory to pursue complete species identification and MIC determinations. Given the current and evolving medical practices for management of seriously ill patients, further evaluations of the clinically important data about these yeasts are needed. PMID:8665465

  10. Production of Xylitol from D-Xylose by Overexpression of Xylose Reductase in Osmotolerant Yeast Candida glycerinogenes WL2002-5.

    PubMed

    Zhang, Cheng; Zong, Hong; Zhuge, Bin; Lu, Xinyao; Fang, Huiying; Zhuge, Jian

    2015-07-01

    Efficient bioconversion of D-xylose into various biochemicals is critical for the developing lignocelluloses application. In this study, we compared D-xylose utilization in Candida glycerinogenes WL2002-5 transformants expressing xylose reductase (XYL1) in D-xylose metabolism. C. glycerinogenes WL2002-5 expressing XYL1 from Schefferomyces stipitis can produce xylitol. Xylitol production by the recombinant strains was evaluated using a xylitol fermentation medium with glucose as a co-substrate. As glucose was found to be an insufficient co-substrate, various carbon sources were screened for efficient cofactor regeneration, and glycerol was found to be the best co-substrate. The effects of glycerol on the xylitol production rate by a xylose reductase gene (XYL1)-overexpressed mutant of C. glycerinogenes WL2002-5 were investigated. The XYL1-overexpressed mutant produced xylitol from D-xylose using glycerol as a co-substrate for cell growth and NAD (P) H regeneration: 100 g/L D-xylose was completely converted into xylitol when at least 20 g/L glycerol was used as a co-substrate. XYL1 overexpressed mutant grown on glycerol as co-substrate accumulated 2.1-fold increased xylitol concentration over those cells grown on glucose as co-substrate. XYL1 overexpressed mutant produced xylitol with a volumetric productivity of 0.83 g/L/h, and a xylitol yield of 98 % xylose. Recombinant yeast strains obtained in this study are promising candidates for xylitol production. This is the first report of XYL1 gene overexpression of C. glycerinogenes WL2002-5 for enhancing the efficiency of xylitol production. PMID:26018342

  11. Production of Xylitol from D-Xylose by Overexpression of Xylose Reductase in Osmotolerant Yeast Candida glycerinogenes WL2002-5.

    PubMed

    Zhang, Cheng; Zong, Hong; Zhuge, Bin; Lu, Xinyao; Fang, Huiying; Zhuge, Jian

    2015-07-01

    Efficient bioconversion of D-xylose into various biochemicals is critical for the developing lignocelluloses application. In this study, we compared D-xylose utilization in Candida glycerinogenes WL2002-5 transformants expressing xylose reductase (XYL1) in D-xylose metabolism. C. glycerinogenes WL2002-5 expressing XYL1 from Schefferomyces stipitis can produce xylitol. Xylitol production by the recombinant strains was evaluated using a xylitol fermentation medium with glucose as a co-substrate. As glucose was found to be an insufficient co-substrate, various carbon sources were screened for efficient cofactor regeneration, and glycerol was found to be the best co-substrate. The effects of glycerol on the xylitol production rate by a xylose reductase gene (XYL1)-overexpressed mutant of C. glycerinogenes WL2002-5 were investigated. The XYL1-overexpressed mutant produced xylitol from D-xylose using glycerol as a co-substrate for cell growth and NAD (P) H regeneration: 100 g/L D-xylose was completely converted into xylitol when at least 20 g/L glycerol was used as a co-substrate. XYL1 overexpressed mutant grown on glycerol as co-substrate accumulated 2.1-fold increased xylitol concentration over those cells grown on glucose as co-substrate. XYL1 overexpressed mutant produced xylitol with a volumetric productivity of 0.83 g/L/h, and a xylitol yield of 98 % xylose. Recombinant yeast strains obtained in this study are promising candidates for xylitol production. This is the first report of XYL1 gene overexpression of C. glycerinogenes WL2002-5 for enhancing the efficiency of xylitol production.

  12. Aerobic decolorization and degradation of Acid Orange G (AOG) by suspended growing cells and immobilized cells of a yeast strain Candida tropicalis TL-F1.

    PubMed

    Tan, Liang; Li, Hua; Ning, Shuxiang; Hao, Jia

    2014-10-01

    In this study, aerobic decolorization and degradation of azo dye Acid Orange G (AOG) by both suspended growing cells and immobilized cells of a yeast strain Candida tropicalis TL-F1 were studied. The effects of different parameters on decolorization of AOG by both growing suspended and immobilized strain TL-F1 were investigated. Furthermore, a possible decolorization mechanism of AOG was proposed through analyzing metabolic intermediates using UV-vis and high-performance liquid chromatography-mass spectrometry (HPLC-MS) methods. Strain TL-F1 could decolorize AOG in both liquid and solid mediums through degradation. The optimal conditions for decolorization with suspended growing cells of strain TL-F1 were as follows: 6-10 g/L sucrose, 5-7 g/L urea, ≥6 % (v/v) inoculation size, ≥160 rpm, 35-40 °C, and pH 5.0-6.0; and those for immobilized cells, the conditions were as follows: 4-6 g/L glucose, 0.2-0.4 g/L urea, 6-10 g/L (wet cell pellets) inoculation size, ≥160 rpm, 35-40 °C, and pH 5.0-7.0. Results of UV-vis scanning spectra suggested that AOG was decolorized through biodegradation, and the possible pathway was proposed through the results of HPLC-MS analysis and related literature. This is a systematic research on aerobic decolorization and degradation of AOG by both suspended and immobilized cells of a C. tropicalis strain.

  13. Inactivation of the Antifungal and Immunomodulatory Properties of Human Cathelicidin LL-37 by Aspartic Proteases Produced by the Pathogenic Yeast Candida albicans

    PubMed Central

    Bochenska, Oliwia; Zawrotniak, Marcin; Wolak, Natalia; Trebacz, Grzegorz; Gogol, Mariusz; Ostrowska, Dominika; Aoki, Wataru; Ueda, Mitsuyoshi; Kozik, Andrzej

    2015-01-01

    Constant cross talk between Candida albicans yeast cells and their human host determines the outcome of fungal colonization and, eventually, the progress of infectious disease (candidiasis). An effective weapon used by C. albicans to cope with the host defense system is the release of 10 distinct secreted aspartic proteases (SAPs). Here, we validate a hypothesis that neutrophils and epithelial cells use the antimicrobial peptide LL-37 to inactivate C. albicans at sites of candidal infection and that C. albicans uses SAPs to effectively degrade LL-37. LL-37 is cleaved into multiple products by SAP1 to -4, SAP8, and SAP9, and this proteolytic processing is correlated with the gradual decrease in the antifungal activity of LL-37. Moreover, a major intermediate of LL-37 cleavage—the LL-25 peptide—is antifungal but devoid of the immunomodulatory properties of LL-37. In contrast to LL-37, LL-25 did not affect the generation of reactive oxygen species by neutrophils upon treatment with phorbol esters. Stimulating neutrophils with LL-25 (rather than LL-37) significantly decreased calcium flux and interleukin-8 production, resulting in lower chemotactic activity of the peptide against neutrophils, which may decrease the recruitment of neutrophils to infection foci. LL-25 also lost the function of LL-37 as an inhibitor of neutrophil apoptosis, thereby reducing the life span of these defense cells. This study indicates that C. albicans can effectively use aspartic proteases to destroy the antimicrobial and immunomodulatory properties of LL-37, thus enabling the pathogen to survive and propagate. PMID:25847962

  14. 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

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  16. Results from the ARTEMIS DISK Global Antifungal Surveillance Study: a 6.5-Year Analysis of Susceptibilities of Candida and Other Yeast Species to Fluconazole and Voriconazole by Standardized Disk Diffusion Testing

    PubMed Central

    Pfaller, M. A.; Diekema, D. J.; Rinaldi, M. G.; Barnes, R.; Hu, B.; Veselov, A. V.; Tiraboschi, N.; Nagy, E.; Gibbs, D. L.

    2005-01-01

    Fluconazole in vitro susceptibility test results for 140,767 yeasts were collected from 127 participating investigators in 39 countries from June 1997 through December 2003. Data were collected on 79,343 yeast isolates tested with voriconazole from 2001 through 2003. All investigators tested clinical yeast isolates by the CLSI (formerly NCCLS) M44-A disk diffusion method. Test plates were automatically read and results were recorded with the BIOMIC Vision Image Analysis System. Species, drug, zone diameter, susceptibility category, and quality control results were collected quarterly via e-mail for analysis. Duplicate (the same patient, same species, and same susceptible-resistant biotype profile during any 7-day period) and uncontrolled test results were not analyzed. The 10 most common species of yeasts all showed less resistance to voriconazole than to fluconazole. Candida krusei showed the largest difference, with over 70% resistance to fluconazole and less than 8% to voriconazole. All species of yeasts tested were more susceptible to voriconazole than to fluconazole, assuming proposed interpretive breakpoints of ≥17 mm (susceptible) and ≤13 mm (resistant) for voriconazole. MICs reported in this study were determined from the zone diameter in millimeters from the continuous agar gradient around each disk, which was calibrated with MICs determined from the standard CLSI M27-A2 broth dilution method by balanced-weight regression analysis. The results from this investigation demonstrate the broad spectrum of the azoles for most of the opportunistic yeast pathogens but also highlight several areas where resistance may be progressing and/or where previously rare species may be “emerging.” PMID:16333066

  17. Detection of amphotericin B resistance in Candida haemulonii and closely related species by use of the Etest, Vitek-2 yeast susceptibility system, and CLSI and EUCAST broth microdilution methods.

    PubMed

    Shin, Jong Hee; Kim, Mi-Na; Jang, Sook Jin; Ju, Min Young; Kim, Soo Hyun; Shin, Myung Geun; Suh, Soon Pal; Ryang, Dong Wook

    2012-06-01

    The emerging fungal pathogens Candida haemulonii and Candida pseudohaemulonii often show high-level resistance to amphotericin B (AMB). We compared the utilities of five antifungal susceptibility testing methods, i.e., the Etest using Mueller-Hinton agar supplemented with glucose and methylene blue (Etest-MH), the Etest using RPMI agar supplemented with glucose (Etest-RPG), the Vitek-2 yeast susceptibility system, and the Clinical and Laboratory Standards Institute (CLSI) and European Committee on Antimicrobial Susceptibility Testing (EUCAST) broth microdilution methods, for the detection of AMB-resistant isolates of C. haemulonii and closely related species. Thirty-eight clinical isolates (8 C. haemulonii, 10 C. pseudohaemulonii, and 20 Candida auris isolates) were analyzed. Of the 18 C. haemulonii and C. pseudohaemulonii isolates, 18, 15, 18, 10, and 9 exhibited AMB MICs of >1 μg/ml by the Etest-MH, Etest-RPG, Vitek-2, CLSI, and EUCAST methods, respectively. All 20 C. auris isolates showed AMB MICs of ≤1 μg/ml by all five methods. Of the methods, the Etest-MH generated the broadest distribution of AMB MICs for all 38 isolates and showed the best discrimination between the C. haemulonii and C. pseudohaemulonii isolates (4 to 32 μg/ml) and those of C. auris (0.125 to 0.5 μg/ml). Taking the Etest-MH as the reference method, the essential agreements (within two dilutions) for the Etest-RPG, Vitek-2, CLSI, and EUCAST methods were 84, 92, 55, and 55%, respectively; the categorical agreements were 92, 92, 79, and 76%, respectively. This study provides the first data on the efficacy of the Etest-MH and its excellent agreement with Vitek-2 for discriminating AMB-resistant from AMB-susceptible isolates of these Candida species.

  18. Evaluation of the use of Congo red staining in the differential diagnosis of Candida vs. various other yeast-form fungal organisms.

    PubMed

    Axelson, Glen K; Giorgadze, Tamar; Youngberg, George A

    2008-01-01

    The Congo red staining properties of Candida organisms in clinical tissue specimens have not, to the best of our knowledge, previously been reported. The objective of this study was to determine if the Congo red staining characteristics of Candida vs. Histoplasma, Pityrosporum and Blastomyces could provide useful diagnostic information. Archival tissue specimens that contained Histoplasma, Pityrosporum, Candida and Blastomyces were stained with Congo red. The results of the Congo red staining were compared with the diagnoses which were originally rendered on the tissue. Nine out of nine cases (100%) of Blastomyces were Gomori methenamine silver (GMS) positive and Congo red positive, seven out of seven cases (100%) of Histoplasma were GMS positive and Congo red negative, and eight out of eight cases (100%) that had Pityrosporum were GMS positive and Congo red positive; these results corroborate with previously described staining patterns for each respective organism. Nine out of nine cases (100%) that had Candida were GMS positive and Congo red negative. Differential Congo red staining of Candida organisms can provide a rapid and accurate method of diagnosis in tissue specimens vs. Blastomyces and Pityrosporum, but not vs. Histoplasma. PMID:18095991

  19. 21 CFR 172.896 - Dried yeasts.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Dried yeasts. 172.896 Section 172.896 Food and... Multipurpose Additives § 172.896 Dried yeasts. Dried yeast (Saccharomyces cerevisiae and Saccharomyces fragilis) and dried torula yeast (Candida utilis) may be safely used in food provided the total folic...

  20. 21 CFR 172.896 - Dried yeasts.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Dried yeasts. 172.896 Section 172.896 Food and... Multipurpose Additives § 172.896 Dried yeasts. Dried yeast (Saccharomyces cerevisiae and Saccharomyces fragilis) and dried torula yeast (Candida utilis) may be safely used in food provided the total folic...

  1. 21 CFR 172.896 - Dried yeasts.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Dried yeasts. 172.896 Section 172.896 Food and... Multipurpose Additives § 172.896 Dried yeasts. Dried yeast (Saccharomyces cerevisiae and Saccharomyces fragilis) and dried torula yeast (Candida utilis) may be safely used in food provided the total folic...

  2. 21 CFR 172.896 - Dried yeasts.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Dried yeasts. 172.896 Section 172.896 Food and... Multipurpose Additives § 172.896 Dried yeasts. Dried yeast (Saccharomyces cerevisiae and Saccharomyces fragilis) and dried torula yeast (Candida utilis) may be safely used in food provided the total folic...

  3. Candida osteomyelitis in a gelding.

    PubMed

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

    2013-02-01

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

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

    PubMed Central

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

    2014-01-01

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

  5. Methanol test

    MedlinePlus

    ... sources of methanol in the body include fruits, vegetables, and diet drinks that contain aspartame. Methanol is ... eat or drink it in toxic amounts. Methanol poisoning mainly affects the digestive system, nervous system, and ...

  6. Description of Diutina gen. nov., Diutina siamensis, f.a. sp. nov., and reassignment of Candida catenulata, Candida mesorugosa, Candida neorugosa, Candida pseudorugosa, Candida ranongensis, Candida rugosa and Candida scorzettiae to the genus Diutina.

    PubMed

    Khunnamwong, Pannida; Lertwattanasakul, Noppon; Jindamorakot, Sasitorn; Limtong, Savitree; Lachance, Marc-André

    2015-12-01

    Three strains (DMKU-RE28, DMKU-RE43T and DMKU-RE123) of a novel anamorphic yeast species were isolated from rice leaf tissue collected in Thailand. DNA sequence analysis demonstrated that the species forms a sister pair with Candida ranongensis CBS 10861T but differs by 24-30 substitutions in the LSU rRNA gene D1/D2 domains and 30-35 substitutions in the ITS region. A phylogenetic analysis based on both the small and the large rRNA gene subunits confirmed this connection and demonstrated the presence of a clade that also includes Candida catenulata, Candida mesorugosa, Candida neorugosa, Candida pseudorugosa, Candida rugosa and Candida scorzettiae. The clade is not closely affiliated to any known teleomorphic genus, and forms a well-separated lineage from currently recognized genera of the Saccharomycetales. Hence, the genus Diutina gen. nov. is proposed to accommodate members of the clade, including Diutina siamensis f.a. sp. nov. and the preceding seven Candida species. The type strain is DMKU-RE43T ( = CBS 13388T = BCC 61183T = NBRC 109695T).

  7. Isoflavone formononetin from red propolis acts as a fungicide against Candida sp.

    PubMed

    das Neves, Michelline Viviane Marques; da Silva, Tânia Maria Sarmento; Lima, Edeltrudes de Oliveira; da Cunha, Emídio Vasconcelos Leitão; Oliveira, Eduardo de Jesus

    2016-01-01

    A bioassay-guided fractionation of two samples of Brazilian red propolis (from Igarassu, PE, Brazil, hereinafter propolis 1 and 2) was conducted in order to determine the components responsible for its antimicrobial activity, especially against Candida spp. Samples of both the crude powdered resin and the crude ethanolic extract of propolis from both locations inhibited the growth of all 12 tested Candida strains, with a minimum inhibitory concentration of 256μg/mL. The hexane, acetate and methanol fractions of propolis 1 also inhibited all strains with minimum inhibitory concentration values ranging from 128 to 512μg/mL for the six bacteria tested and from 32 to 1024μg/mL for the yeasts. Similarly, hexane and acetate fractions of propolis sample 2 inhibited all microorganisms tested, with minimum inhibitory concentration values of 512μg/mL for bacteria and 32μg/mL for yeasts. The extracts were analyzed by HPLC and their phenolic profile allowed us to identify and quantitate one phenolic acid and seven flavonoids in the crude ethanolic extract. Formononetin and pinocembrin were the major constituents amongst the identified compounds. Formononetin was detected in all extracts and fractions tested, except for the methanolic fraction of sample 2. The isolated isoflavone formononetin inhibited the growth of all the microorganisms tested, with a minimum inhibitory concentration of 200μg/mL for the six bacteria strains tested and 25μg/mL for the six yeasts. Formononetin also exhibited fungicidal activity against five of the six yeasts tested. Taken together our results demonstrate that the isoflavone formononetin is implicated in the reported antimicrobial activity of red propolis.

  8. Isoflavone formononetin from red propolis acts as a fungicide against Candida sp

    PubMed Central

    das Neves, Michelline Viviane Marques; da Silva, Tânia Maria Sarmento; Lima, Edeltrudes de Oliveira; da Cunha, Emídio Vasconcelos Leitão; Oliveira, Eduardo de Jesus

    2016-01-01

    A bioassay-guided fractionation of two samples of Brazilian red propolis (from Igarassu, PE, Brazil, hereinafter propolis 1 and 2) was conducted in order to determine the components responsible for its antimicrobial activity, especially against Candida spp. Samples of both the crude powdered resin and the crude ethanolic extract of propolis from both locations inhibited the growth of all 12 tested Candida strains, with a minimum inhibitory concentration of 256 μg/mL. The hexane, acetate and methanol fractions of propolis 1 also inhibited all strains with minimum inhibitory concentration values ranging from 128 to 512 μg/mL for the six bacteria tested and from 32 to 1024 μg/mL for the yeasts. Similarly, hexane and acetate fractions of propolis sample 2 inhibited all microorganisms tested, with minimum inhibitory concentration values of 512 μg/mL for bacteria and 32 μg/mL for yeasts. The extracts were analyzed by HPLC and their phenolic profile allowed us to identify and quantitate one phenolic acid and seven flavonoids in the crude ethanolic extract. Formononetin and pinocembrin were the major constituents amongst the identified compounds. Formononetin was detected in all extracts and fractions tested, except for the methanolic fraction of sample 2. The isolated isoflavone formononetin inhibited the growth of all the microorganisms tested, with a minimum inhibitory concentration of 200 μg/mL for the six bacteria strains tested and 25 μg/mL for the six yeasts. Formononetin also exhibited fungicidal activity against five of the six yeasts tested. Taken together our results demonstrate that the isoflavone formononetin is implicated in the reported antimicrobial activity of red propolis. PMID:26887239

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

    PubMed Central

    2011-01-01

    Background Sterol biosynthesis is an essential pathway for fungal survival, and is the biochemical target of many antifungal agents. The antifungal drugs most widely used to treated fungal infections are compounds that inhibit cytochrome P450-dependent C14α-demethylase (CYP51), but other enzymes of this pathway, such as squalene synthase (SQS) which catalyses the first committed step in sterol biosynthesis, could be viable targets. The aim of this study was to evaluate the antifungal activity of SQS inhibitors on Candida albicans, Candida tropicalis and Candida parapsilopsis strains. Methods Ten arylquinuclidines that act as SQS inhibitors were tested as antiproliferative agents against three ATCC strains and 54 clinical isolates of Candida albicans, Candida tropicalis and Candida parapsilopsis. Also, the morphological alterations induced in the yeasts by the experimental compounds were evaluated by fluorescence and transmission electron microscopy. Results The most potent arylquinuclidine derivative (3-[1'-{4'-(benzyloxy)-phenyl}]-quinuclidine-2-ene) (WSP1267) had a MIC50 of 2 μg/ml for all species tested and MIC90 varying from 4 μg/ml to 8 μg/ml. Ultrathin sections of C. albicans treated with 1 μg/ml of WSP1267 showed several ultrastructural alterations, including (a) loss of cell wall integrity, (b) detachment of the plasma membrane from the fungal cell wall, (c) accumulation of small vesicles in the periplasmic region, (d) presence of large electron-dense vacuoles and (e) significantly increased cell size and cell wall thickness. In addition, fluorescence microscopy of cells labelled with Nile Red showed an accumulation of lipid droplets in the cytoplasm of treated yeasts. Nuclear staining with DAPI revealed the appearance of uncommon yeast buds without a nucleus or with two nuclei. Conclusion Taken together, our data demonstrate that arylquinuclidine derivatives could be useful as lead compounds for the rational synthesis of new antifungal drugs. PMID

  10. Evaluation of a Reformulated CHROMagar Candida

    PubMed Central

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

    2001-01-01

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

  11. n-alkanes as a substratum for riboflavin production. I. Investigations of the dynamics of the flavinogenesis in chosen yeasts of the genus candida.

    PubMed

    Olczyk, C

    1978-01-01

    For the first time the flavinogenic abilities of Candida flareri on a simple, fully defined medium with hydrocarbons were demonstrated. C flareri and C. guilliermondi on a synthetic medium with biotin and n-alkanes (n-decane and hexadecane) overproduce riboflavin with a considerable but varying efficiency. Among the two hydrocarbons examined n-hexadecane proved to be a more favourable source of carbon for the biosynthesis of this vitamin than n-decane. The quantities of riboflavin accumulated by C. flareri in an aerated culture are twice higher than those for C. guilliermondii (50.5 microgram/ml on hexadecane) in analogous conditions. PMID:643742

  12. Commensal Oral Candida in Asian Cohorts

    PubMed Central

    Samaranayake, Lakshman

    2009-01-01

    The oral carriage rate of Candida in healthy humans ranges from 40% to 60%. However for a prolonged period, the oral candidal prevalence in humans was documented essentially using data from studies in the West as their prevalence in inhabitants in different regions of the world, including Asia was not known. Yet, recent reports from a number of studies indicate the quality, quantity and prevalence of oral yeasts differ between Asia and other regions for reason that are still unclear. This mini review on such data from Asian studies on oral carriage of Candida provides another intriguing facet of the behavior of this ubiquitous yeast. PMID:20690497

  13. “In vitro” antifungal activity of ozonized sunflower oil on yeasts from onychomycosis

    PubMed Central

    Guerrer, L.V.; Cunha, K. C.; Nogueira, M. C. L.; Cardoso, C. C.; Soares, M. M. C. N.; Almeida, M. T. G.

    2012-01-01

    The “in vitro” antifungal activity of ozonized sunflower oil (Bioperoxoil®) was tested on 101 samples of yeasts originating from onychomycosis using the disk diffusion method. The oil was efficacious against several clinical fungal strains: Candida parapsilosis, Candida albicans, Trichosporon asahii, Candida tropicalis and Candida guilliermondii. PMID:24031958

  14. Overexpression of the Candida albicans ALA1 Gene in Saccharomyces cerevisiae Results in Aggregation following Attachment of Yeast Cells to Extracellular Matrix Proteins, Adherence Properties Similar to Those of Candida albicans

    PubMed Central

    Gaur, Nand K.; Klotz, Stephen A.; Henderson, Ramona L.

    1999-01-01

    Candida albicans maintains a commensal relationship with human hosts, probably by adhering to mucosal tissue in a variety of physiological conditions. We show that adherence due to the C. albicans gene ALA1 when transformed into Saccharomyces cerevisiae, is comprised of two sequential steps. Initially, C. albicans rapidly attaches to extracellular matrix (ECM) protein-coated magnetic beads in small numbers (the attachment phase). This is followed by a relatively slower step in which cell-to-cell interactions predominate (the aggregation phase). Neither of these phases is observed in S. cerevisiae. However, expression of the C. albicans ALA1 gene from a low-copy vector causes S. cerevisiae transformants to attach to ECM-coated magnetic beads without appreciable aggregation. Expression of ALA1 from a high-copy vector results in both attachment and aggregation. Moreover, transcriptional fusion of ALA1 with the galactose-inducible promoters GALS, GALL, and GAL1, allowing for low, moderate, and high levels of inducible transcription, respectively, causes attachment and aggregation that correlates with the strength of the GAL promoter. The adherence of C. albicans and S. cerevisiae overexpressing ALA1 to a number of protein ligands occurs over a broad pH range, is resistant to shear forces generated by vortexing, and is unaffected by the presence of sugars, high salt levels, free ligands, or detergents. Adherence is, however, inhibited by agents that disrupt hydrogen bonds. The similarities in the adherence and aggregation properties of C. albicans and S. cerevisiae overexpressing ALA1 suggest a role in adherence and aggregation for ALA1 and ALA1-like genes in C. albicans. PMID:10531265

  15. Sustained Nitric Oxide-Releasing Nanoparticles Induce Cell Death in Candida albicans Yeast and Hyphal Cells, Preventing Biofilm Formation In Vitro and in a Rodent Central Venous Catheter Model

    PubMed Central

    Ahmadi, Mohammed S.; Lee, Hiu Ham; Sanchez, David A.; Friedman, Adam J.; Tar, Moses T.; Davies, Kelvin P.; Nosanchuk, Joshua D.

    2016-01-01

    Candida albicans is a leading nosocomial pathogen. Today, candidal biofilms are a significant cause of catheter infections, and such infections are becoming increasingly responsible for the failure of medical-implanted devices. C. albicans forms biofilms in which fungal cells are encased in an autoproduced extracellular polysaccharide matrix. Consequently, the enclosed fungi are protected from antimicrobial agents and host cells, providing a unique niche conducive to robust microbial growth and a harbor for recurring infections. Here we demonstrate that a recently developed platform comprised of nanoparticles that release therapeutic levels of nitric oxide (NO-np) inhibits candidal biofilm formation, destroys the extracellular polysaccharide matrices of mature fungal biofilms, and hinders biofilm development on surface biomaterials such as the lumen of catheters. We found NO-np to decrease both the metabolic activity of biofilms and the cell viability of C. albicans in vitro and in vivo. Furthermore, flow cytometric analysis found NO-np to induce apoptosis in biofilm yeast cells in vitro. Moreover, NO-np behave synergistically when used in combination with established antifungal drug therapies. Here we propose NO-np as a novel treatment modality, especially in combination with standard antifungals, for the prevention and/or remediation of fungal biofilms on central venous catheters and other medical devices. PMID:26810653

  16. 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

  17. Morphological, biochemical and molecular characterisation of the first Italian Candida africana isolate.

    PubMed

    Romeo, Orazio; Criseo, Giuseppe

    2009-09-01

    One atypical isolate of the pathogenic yeast Candida albicans was isolated from an Italian patient with vulvovaginitis. The strain, germ tube positive and chlamydospore-negative showed white-thin turquoise colonies on Candida ID 2 medium. The yeast was identified as Candida africana by using morphological and biochemical tests. On the basis of the molecular results obtained in this study as well as in other studies, C. africana cannot be yet considered as a new species of Candida. It is possible that C. africana represents a new variant of C. albicans like the well-known Candida stellatoidea. To our knowledge, this is the first isolation of C. africana in Italy.

  18. High-Quality Draft Genome Sequence of Candida apicola NRRL Y-50540.

    PubMed

    Vega-Alvarado, Leticia; Gómez-Angulo, Jorge; Escalante-García, Zazil; Grande, Ricardo; Gschaedler-Mathis, Anne; Amaya-Delgado, Lorena; Sanchez-Flores, Alejandro; Arrizon, Javier

    2015-01-01

    Candida apicola, a highly osmotolerant ascomycetes yeast, produces sophorolipids (biosurfactants), membrane fatty acids, and enzymes of biotechnological interest. The genome obtained has a high-quality draft for this species and can be used as a reference to perform further analyses, such as differential gene expression in yeast from Candida genera. PMID:26067948

  19. High-Quality Draft Genome Sequence of Candida apicola NRRL Y-50540

    PubMed Central

    Vega-Alvarado, Leticia; Gómez-Angulo, Jorge; Escalante-García, Zazil; Grande, Ricardo; Gschaedler-Mathis, Anne; Amaya-Delgado, Lorena

    2015-01-01

    Candida apicola, a highly osmotolerant ascomycetes yeast, produces sophorolipids (biosurfactants), membrane fatty acids, and enzymes of biotechnological interest. The genome obtained has a high-quality draft for this species and can be used as a reference to perform further analyses, such as differential gene expression in yeast from Candida genera. PMID:26067948

  20. Stubborn vaginal yeast infections.

    PubMed

    1994-01-01

    Fungi, which along with plants and animals comprise a distinct group in the classification of living things, break down and recycle organic matter. One sub-group with over 600 varieties consists of microscopic, single-celled yeasts. Of the genus Candida, the species Candida albicans accounts for 94% of all cases of fungal vaginitis. Yeasts thrive in human bodies as either beneficial or pathogenic agents. Even when they are an innocuous presence in a healthy human body, they are always poised to create opportunistic infections in susceptible individuals. Candida has been known to infect every organ of the body, but its ability to cause infection depends upon the presence of a sufficient amount of fungal organisms or generally reduced resistance or both. Often use of modern medical drugs such as oral contraceptives, antibiotics, or immunosuppressant drugs can trigger an infection. The symptoms of vaginal infection are vaginal itching, inflammation, and swelling; a burning sensation; and a white, cheesy discharge. Yeast infections can occur in females of all ages (although they are most common in women of child-bearing age) and prompt a large percentage of trips to the gynecologist. Recurrence is common, and each occurrence is harder to eradicate. Often frustrated women turn to alternative therapies. Successful treatment depends upon reducing the yeast population in the body, building up the beneficial bacteria population, limiting and controlling yeast triggers, and strengthening overall health. PMID:12318962

  1. Production and characterization of an extracellular lipase from Candida guilliermondii

    PubMed Central

    Oliveira, Anne Caroline Defranceschi; Fernandes, Maria Luiza; Mariano, André Bellin

    2014-01-01

    Extracellular lipases from the endophytic yeast Candida guilliermondii isolated from castor leaves (Ricinus communis L.) were produced using low-cost raw materials such as agro-industrial residues and applying them in the esterification of oleic acid for evaluating their potential use in biodiesel production. After partial purification using ammonium sulfate, the enzyme was characterized and presented higher activity (26.8 ± 1.5 U mL−1) in the presence of 5 mmol L−1 NaCl at 30 °C and pH 6.5. The production through submerged fermentation was formerly performed in 150 mL erlenmeyer flasks and, once the enzyme production was verified, assays in a 14 L bioreactor were conducted, obtaining 18 ± 1.4 U mL−1. The produced enzyme was applied in the oleic acid esterification under different solvents: hexane, cyclohexane or cyclohexanone) and different acid:alcohol molar ratios. Higher ester conversion rate (81%) was obtained using hexane and the molar ratio of 1:9 was the best conditions using methanol. The results suggest the potential for development of endophytic yeast in the production of biocatalyst through submerged fermentation using agroindustrial residues as culture medium. PMID:25763060

  2. Comparison of Three Statistical Methods for Establishing Tentative Wild-Type Population and Epidemiological Cutoff Values for Echinocandins, Amphotericin B, Flucytosine, and Six Candida Species as Determined by the Colorimetric Sensititre YeastOne Method

    PubMed Central

    Pemán, Javier; Hervás, David; Iñiguez, Carmen; Navarro, David; Echeverría, Julia; Martínez-Alarcón, José; Fontanals, Dionisia; Gomila-Sard, Bárbara; Buendía, Buenaventura; Torroba, Luis; Ayats, Josefina; Bratos, Angel; Sánchez-Reus, Ferran; Fernández-Natal, Isabel

    2012-01-01

    The Sensititre YeastOne (SYO) method is a widely used method to determine the susceptibility of Candida spp. to antifungal agents. CLSI clinical breakpoints (CBP) have been reported for antifungals, but not using this method. In the absence of CBP, epidemiological cutoff values (ECVs) are useful to separate wild-type (WT) isolates (those without mechanisms of resistance) from non-WT isolates (those that can harbor some resistance mechanisms), which is the goal of any susceptibility test. The ECVs for five agents, obtained using the MIC distributions determined by the SYO test, were calculated and contrasted with those for three statistical methods and the MIC50 and modal MIC, both plus 2-fold dilutions. The median ECVs (in mg/liter) (% of isolates inhibited by MICs equal to or less than the ECV; number of isolates tested) of the five methods for anidulafungin, micafungin, caspofungin, amphotericin B, and flucytosine, respectively, were as follows: 0.25 (98.5%; 656), 0.06 (95.1%; 659), 0.25 (98.7%; 747), 2 (100%; 923), and 1 (98.5%; 915) for Candida albicans; 8 (100%; 352), 4 (99.2%; 392), 2 (99.2%; 480), 1 (99.8%; 603), and 0.5 (97.9%; 635) for C. parapsilosis; 1 (99.2%; 123), 0.12 (99.2%; 121), 0.25 (99.2%; 138), 2 (100%; 171), and 0.5 (97.2%; 175) for C. tropicalis; 0.12 (96.6%; 174), 0.06 (96%; 176), 0.25 (98.4%; 188), 2 (100%; 209), and 0.25 (97.6%; 208) for C. glabrata; 0.25 (97%; 33), 0.5 (93.9%; 33), 1 (91.9%; 37), 4 (100%; 51), and 32 (100%; 53) for C. krusei; and 4 (100%; 33), 2 (100%; 33), 2 (100%; 54), 1 (100%; 90), and 0.25 (93.4%; 91) for C. orthopsilosis. The three statistical methods gave similar ECVs (within one dilution) and included ≥95% of isolates. These tentative ECVs would be useful for monitoring the emergence of isolates with reduced susceptibility by use of the SYO method. PMID:23015676

  3. Heterogeneous activity of immature and mature cells of the murine monocyte-macrophage lineage derived from different anatomical districts against yeast-phase Candida albicans.

    PubMed Central

    Decker, T; Lohmann-Matthes, M L; Baccarini, M

    1986-01-01

    Mature mononuclear phagocytes have been receiving much attention as effectors of spontaneous candidacidal activity, although with controversial results due to differences in the effector populations and the methods used in different laboratories. We here systematically compare the fungistatic activity of immature and mature cells of the murine macrophage series. The results show that nonadherent, nonphagocytic precursor cells (isolated either [90% purity] from bone marrow liquid cultures or from the organs of mice in which inflammatory conditions had been elicited in vivo) exerted a strong extracellular candidastatic activity. In contrast, mature macrophages, either obtained from different anatomical areas (spleen, liver, lung, peritoneal cavity) or matured in vitro from the precursor populations, displayed striking heterogeneity in their ability to inhibit the growth of Candida albicans, depending on the anatomical site they were derived from. Lymphokine activation did not alter the fungistatic pattern of the untreated cells. The different macrophage populations behaved very differently also in the production of reactive oxygen intermediates (ROI) in response to phagocytosis of C. albicans. The amounts of ROI generated, however, showed no correlation with candidastatic ability. Low levels of candidastatic activity exerted by resident peritoneal macrophages (good ROI producers) were inhibited by catalase, whereas high levels of growth inhibition by Kupffer cells (poor ROI producers) after 8 h of assay were hardly influenced by the enzyme. Our data suggest the existence of two different effector mechanisms in macrophage-mediated C. albicans growth inhibition, a rather inefficient ROI-dependent one, and a second, very efficient oxygen-independent mechanism. The implications of these findings are discussed. PMID:3533781

  4. Candida africana and its closest relatives.

    PubMed

    Romeo, Orazio; Criseo, Giuseppe

    2011-11-01

    Candida africana is a recently described opportunistic yeast pathogen that has been linked to vaginal candidiasis. This yeast was first described, in 1995, as atypical chlamydospore-negative Candida albicans strain, and subsequently proposed as a new Candida species on the basis of morphological, biochemical and physiological characteristics clearly different from those of typical C. albicans isolates. Phylogenetic studies based on the comparison of ribosomal DNA sequences demonstrated that C. africana and C. albicans isolates are too closely related to draw any conclusions regarding the status of a new species. Therefore, on the basis of these studies, some authors considered C. africana as a biovar of C. albicans even if genetic differences may be found if additional regions of genomic DNA are sequenced. The taxonomic situation of C. africana and its phylogenetic relationship with other Candida species is still controversial and remains, at present, a matter of debate. Our goal is to review the current knowledge about C. africana and highlight the development of rapid and accurate tests for its discrimination from C. albicans, Candida dubliniensis and Candida stellatoidea. Furthermore, through the analysis of literature data, we have found that C. africana has a worldwide distribution and a considerable number of features making its study particularly interesting.

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

    PubMed

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

    2013-01-01

    Orthopedic surgeons are becoming more involved in the care of patients with septic arthritis and bursitis caused by yeast species. This case report involves a middle-aged immunocompromised female who developed a Candida glabrata septic olecranon bursitis that developed after she received a corticosteroid injection in the olecranon bursa for presumed aseptic bursitis. Candida (Torulopsis) glabrata is the second most frequently isolated Candida species from the bloodstream in the United States. Increased use of fluconazole and other azole antifungal agents as a prophylactic treatment for recurrent Candida albicans infections in immunocompromised individuals is one reason why there appears to be increased resistance of C. glabrata and other nonalbicans Candida (NAC) species to fluconazole. In this patient, this infection was treated with surgery (bursectomy) and intravenous caspofungin, an echinocandin. This rare infectious etiology coupled with this intravenous antifungal treatment makes this case novel among cases of olecranon bursitis caused by yeasts. PMID:23628576

  6. Alcohol-mediated haemolysis in yeast.

    PubMed

    Shuster, Amir; Osherov, Nir; Rosenberg, Mel

    2004-12-01

    Although yeast are generally non-haemolytic, we have found that addition of alcohol vapour confers haemolytic properties on many strains of yeast and other fungi. We have called this phenomenon 'microbial alcohol-conferred haemolysis' (MACH). MACH is species- and strain-specific: whereas all six Candida tropicalis strains tested were haemolytic in the presence of ethanol, none among 10 C. glabrata strains tested exhibited this phenomenon. Among 27 C. albicans strains and 11 Saccharomyces cerevisiae strains tested, ethanol-mediated haemolysis was observed in 11 and 4 strains, respectively. Haemolysis is also dependent on the alcohol moiety: n-butanol and n-pentanol could also confer haemolysis, whereas methanol and 2-propanol did not. Haemolysis was found to be dependent on initial oxidation of the alcohol. Reduced haemolysis was observed in specific alcohol dehydrogenase mutants of both Aspergillus nidulans and S. cerevisiae. MACH was not observed during anaerobic growth, and was reduced in the presence of pararosaniline, an aldehyde scavenger. Results suggest that initial oxidation of the alcohol to the corresponding aldehyde is an essential step in the observed phenomenon.

  7. Resolutive Candida utilis fungemia in a nonneutropenic patient.

    PubMed Central

    Bougnoux, M E; Gueho, E; Potocka, A C

    1993-01-01

    We report here the second case of Candida utilis infection in humans. The patient was apparently immunocompetent, had no central catheter, and survived an 8-day fungemia. Genomic analysis confirmed the conspecificity of medical and industrial strains of C. utilis and that of the anamorphic yeast C. utilis with the teleomorphic yeast Pichia jadinii. PMID:8315009

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

    PubMed

    Fountain, Michelle T; Hopkin, Steve P

    2005-01-01

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

  9. 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.

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

    PubMed Central

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

    2006-01-01

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

  11. In vitro activity of a new polyene, SPA-S-843, against yeasts.

    PubMed

    Rimaroli, C; Bruzzese, T

    1998-11-01

    The in vitro activity of a new water-soluble polyene, SPA-S-843, was evaluated against 116 strains of Candida, Cryptococcus, and Saccharomyces spp. and compared with that of amphotericin B. SPA-S-843 demonstrated better inhibitory activity against all of the yeasts examined and better fungicidal activity against Candida albicans, Candida glabrata, Candida krusei, and Candida tropicalis than did amphotericin B.

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

    PubMed Central

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

    2010-01-01

    Introduction Identification of yeast isolated from clinical specimens to the species level has become increasingly important. Ever-increasing numbers of immuno-suppressed patients, a widening range of recognized pathogens, and the discovery of resistance to antifungal drugs are contributing factors to this necessity. Material and methods A total of 487 yeast strains were studied for the primary isolation and presumptive identification, directly from clinical specimen. Efficacy of CHROMagar Candida has been evaluated with conventional methods including morphology on Corn meal–tween 80 agar and biochemical methods by using API 20 C AUX. Results The result of this study shows that CHROMagar Candida can easily identify three species of Candida on the basis of colonial color and morphology, and accurately differentiate between them i.e. Candida albicans, Candida tropicalis, and Candida krusei. The specificity and sensitivity of CHROMagar Candida for C. albicans calculated as 99%, for C. tropicalis calculated as 98%, and C. krusei it is 100%. Conclusion The data presented supports the use of CHROMagar Candida for the rapid identification of Candida species directly from clinical specimens in resource-limited settings, which could be very helpful in developing appropriate therapeutic strategy and management of patients. PMID:21483597

  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. PMID:25480879

  14. Crystal violet staining to quantify Candida adhesion to epithelial cells.

    PubMed

    Negri, M; Gonçalves, V; Silva, S; Henriques, M; Azeredo, J; Oliveira, R

    2010-01-01

    In vitro studies of adhesion capability are essential to characterise the virulence of Candida species. However, the assessment of adhesion by traditional methods is time-consuming. The aim of the present study is the development of a simple methodology using crystal violet staining to quantify in vitro adhesion of different Candida species to epithelial cells. The experiments are performed using Candida albicans (ATCC 90028), C. glabrata (ATCC 2001), C. parapsilosis (ATCC 22019) and C. tropicalis (ATCC 750). A human urinary bladder epithelial cell line (TCC-SUP) is used. Yeast and epithelial cells were stained with crystal violet, epithelial cells were then destained using intermediate washing, and the dye in the yeast cells was extracted with acetic acid. The method was validated for the different Candida reference species by comparison with traditional microscope observation and enumeration. The method was then used to assess Candida adhesion to epithelial cells and also to silicone. For all Candida spp. high correlation values (r2= 0.9724-0.9997) between the number of adherent yeasts (microscope enumeration) and absorbance values were obtained for an inoculum concentration >10(6) cells/mL. The proposed technique was easy to perform and reproducible, enabling the determination of adhesion ability of Candida species to an epithelial cell line. PMID:20973406

  15. Use of Autobac 1 for rapid assimilation testing of Candida and Torulopsis species.

    PubMed Central

    Ngui Yen, J H; Smith, J A

    1978-01-01

    We devised a system of presumptive identification of some yeasts that uses the Autobac 1 (Pfizer Inc.) instrument to detect carbon assimilation by 218 strains of Candida and Torulopsis. This system compared favorably with a conventional system of yeast identification and also with the Uni-Yeast-Tek (Corning Medical) and API (Analytab Products Inc.) methods. PMID:344333

  16. Conversion of pentoses by yeasts

    SciTech Connect

    Gong, C.S.; Claypool, T.A.; Maun, C.M.; Mccracken, L.D.; Tsao, G.T.; Ueng, P.P.

    1983-01-01

    The utilization and conversion of D-xylose, D-xyulose, L-arabinose, and xylitol by yeast strains have been investigated with the following results: 1) The majority of yeasts tested utilize D-xylose and produce polyols, ethanol, and organic acids. The type and amount of products formed varies with the yeast strains used. The most commonly detected product is xylitol. 2) The majority of yeasts tested utilize D-xylulose aerobically and fermentatively to produce ethanol, xylitol D-arabitol, and organic acids. The type and amount of products varies depending upon the yeast strains used. 3) Xylitol is a poor carbon and energy source for most yeasts tested. Some yeast strains produce small amounts of ethanol from xylitol. 4) Most yeast strains utilize L-arabinose, and L-arabitol is the common product. Small amounts of ethanol are also produced by some yeast strains. 5) Of the four substrates examined, D-xylulose was the preferred substrate, followed by D-xylose, L-arabinose, and xylitol. 6) Mutant yeast strains that exhibit different metabolic product patterns can be induced and isolated from Candida sp. Saccharomyces cerevisiae, and other yeasts. These mutant strains can be used for ethanol production from D-xylose as well as for the study of metabolic regulation of pentose utilization in yeasts.

  17. Trm1p, a Zn(II)₂Cys₆-type transcription factor, is essential for the transcriptional activation of genes of methanol utilization pathway, in Pichia pastoris.

    PubMed

    Sahu, Umakant; Krishna Rao, Kamisetty; Rangarajan, Pundi N

    2014-08-15

    The zinc finger transcription factors Mxr1p and Rop are key regulators of methanol metabolism in the methylotrophic yeast, Pichia pastoris, while Trm1p and Trm2p regulate methanol metabolism in Candida boidinii. Here, we demonstrate that Trm1p is essential for the expression of genes of methanol utilization (mut) pathway in P. pastoris as well. Expression of AOXI and other genes of mut pathway is severely compromised in P. pastoris ΔTrm1 strain resulting in impaired growth on media containing methanol as the sole source of carbon. Trm1p localizes to the nucleus of cells cultured on glucose or methanol. The zinc finger domain of Mxr1p but not Trm1p binds to AOXI promoter sequences in vitro, indicating that these two positive regulators act by different mechanisms. We conclude that both Trm1p and Mxr1p are essential for the expression of genes of mut pathway in P. pastoris and the mechanism of transcriptional regulation of mut pathway may be similar in P. pastoris and C. boidinii.

  18. 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.

  19. 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. PMID:26781374

  20. Recombinant protein expression in Pichia pastoris strains with an engineered methanol utilization pathway

    PubMed Central

    2012-01-01

    Βackground The methylotrophic yeast Pichia pastoris has become an important host organism for recombinant protein production and is able to use methanol as a sole carbon source. The methanol utilization pathway describes all the catalytic reactions, which happen during methanol metabolism. Despite the importance of certain key enzymes in this pathway, so far very little is known about possible effects of overexpressing either of these key enzymes on the overall energetic behavior, the productivity and the substrate uptake rate in P. pastoris strains. Results A fast and easy-to-do approach based on batch cultivations with methanol pulses was used to characterize different P. pastoris strains. A strain with MutS phenotype was found to be superior over a strain with Mut+ phenotype in both the volumetric productivity and the efficiency in expressing recombinant horseradish peroxidase C1A. Consequently, either of the enzymes dihydroxyacetone synthase, transketolase or formaldehyde dehydrogenase, which play key roles in the methanol utilization pathway, was co-overexpressed in MutS strains harboring either of the reporter enzymes horseradish peroxidase or Candida antarctica lipase B. Although the co-overexpression of these enzymes did not change the stoichiometric yields of the recombinant MutS strains, significant changes in the specific growth rate, the specific substrate uptake rate and the specific productivity were observed. Co-overexpression of dihydroxyacetone synthase yielded a 2- to 3-fold more efficient conversion of the substrate methanol into product, but also resulted in a reduced volumetric productivity. Co-overexpression of formaldehyde dehydrogenase resulted in a 2-fold more efficient conversion of the substrate into product and at least similar volumetric productivities compared to strains without an engineered methanol utilization pathway, and thus turned out to be a valuable strategy to improve recombinant protein production. Conclusions Co

  1. [Useful phenotypic characteristics for presumptive identification of Candida guilliermondii].

    PubMed

    Pinoni, M V; Castán, V; Maegli, M I; Lorenzo, J; Frizzera, F; Jewtuchowicz, V; Mujica, M T

    2007-01-01

    Candida guilliermondii developed a pink-purplish colony on CHROMagar Candida. In the micromorphology in milk-tween 80 1% agar at 28 degrees C after 48 h of incubation C. guilliermondii showed small (3-5 microm), spherical yeasts without pseudohyphaes. This Candida species presented a characteristic cluster of blastospores with pseudohyphaes radiating from the centre at 96 h. The trehalose-sucrose assimilation assay was applied to the C. guilliermondii isolates which proved negative for trehalose and positive for sucrose. These results allowed for the presumptive identification of C. guilliermondii. The results were concordant in 100% of the isolates with the identification of the C. guilliermondii species by the ID 32C and Vitek YBC methods. Such automated methods offered Candida famata as a second option, with a reliability percentage of 10%. Micromorphological studies increase yeast identification reliability, especially among species presenting similar biochemical profiles. PMID:17702251

  2. Biofilm Formation by Candida dubliniensis

    PubMed Central

    Ramage, Gordon; Vande Walle, Kacy; Wickes, Brian L.; López-Ribot, José L.

    2001-01-01

    Candida dubliniensis is an opportunistic yeast closely related to Candida albicans that has been recently implicated in oropharyngeal candidiasis in human immunodeficiency virus-infected patients. Most manifestations of candidiasis are associated with biofilm formation, with cells in biofilms displaying properties dramatically different from free-living cells grown under normal laboratory conditions. Here, we report on the development of in vitro models of C. dubliniensis biofilms on the surfaces of biomaterials (polystyrene and acrylic) and on the characteristics associated with biofilm formation by this newly described species. Time course analysis using a formazan salt reduction assay to monitor metabolic activities of cells within the biofilm, together with microscopy studies, revealed that biofilm formation by C. dubliniensis occurred after initial focal adherence, followed by growth, proliferation, and maturation over 24 to 48 h. Serum and saliva preconditioning films enhanced the initial attachment of C. dubliniensis and subsequent biofilm formation. Scanning electron microscopy and confocal scanning laser microscopy were used to further characterize C. dubliniensis biofilms. Mature C. dubliniensis biofilms consisted of a dense network of yeasts cells and hyphal elements embedded within exopolymeric material. C. dubliniensis biofilms displayed spatial heterogeneity and an architecture showing microcolonies with ramifying water channels. Antifungal susceptibility testing demonstrated the increased resistance of sessile C. dubliniensis cells, including the type strain and eight different clinical isolates, against fluconazole and amphotericin B compared to their planktonic counterparts. C. dubliniensis biofilm formation may allow this species to maintain its ecological niche as a commensal and during infection with important clinical repercussions. PMID:11526156

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    DNA sequence analysis has shown Candida abiesophila (NRRL Y-11514T, CBS 5366T) and Candida asiatica (NRRL Y-63747T, CBS 10863T) to be members of a small clade that is phylogenetically separate from other yeasts. In view of their isolation from neighboring genera, such as Pichia and Saturnispora, the...

  4. Candida famata (Debaryomyces hansenii)

    NASA Astrophysics Data System (ADS)

    Sibirny, Andriy A.; Voronovsky, Andriy Y.

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

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

    PubMed Central

    Odds, F C; Bernaerts, R

    1994-01-01

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

  6. [Biomineralization of copper in Candida fukuyamaensis RCL-3].

    PubMed

    Irazusta, Verónica; Michel, Lucas; de Figueroa, Lucía I C

    2016-01-01

    Candida fukuyamaensis RCL-3 yeast has the ability to decrease copper concentration in a culture medium. High copper concentrations change the cell color from white/cream to brown. The effect of color change ceases with the addition of KCN or when cells are grown in a culture medium without sulfate ions. These results could be associated with CuS bioaccumulation in the cell surface. This report revealed that mineralization would be a mechanism used by this yeast for copper bioremediation.

  7. Nitrile Metabolizing Yeasts

    NASA Astrophysics Data System (ADS)

    Bhalla, Tek Chand; Sharma, Monica; Sharma, Nitya Nand

    Nitriles and amides are widely distributed in the biotic and abiotic components of our ecosystem. Nitrile form an important group of organic compounds which find their applications in the synthesis of a large number of compounds used as/in pharmaceutical, cosmetics, plastics, dyes, etc>. Nitriles are mainly hydro-lyzed to corresponding amide/acid in organic chemistry. Industrial and agricultural activities have also lead to release of nitriles and amides into the environment and some of them pose threat to human health. Biocatalysis and biotransformations are increasingly replacing chemical routes of synthesis in organic chemistry as a part of ‘green chemistry’. Nitrile metabolizing organisms or enzymes thus has assumed greater significance in all these years to convert nitriles to amides/ acids. The nitrile metabolizing enzymes are widely present in bacteria, fungi and yeasts. Yeasts metabolize nitriles through nitrilase and/or nitrile hydratase and amidase enzymes. Only few yeasts have been reported to possess aldoxime dehydratase. More than sixty nitrile metabolizing yeast strains have been hither to isolated from cyanide treatment bioreactor, fermented foods and soil. Most of the yeasts contain nitrile hydratase-amidase system for metabolizing nitriles. Transformations of nitriles to amides/acids have been carried out with free and immobilized yeast cells. The nitrilases of Torulopsis candida>and Exophiala oligosperma>R1 are enantioselec-tive and regiospecific respectively. Geotrichum>sp. JR1 grows in the presence of 2M acetonitrile and may have potential for application in bioremediation of nitrile contaminated soil/water. The nitrilase of E. oligosperma>R1 being active at low pH (3-6) has shown promise for the hydroxy acids. Immobilized yeast cells hydrolyze some additional nitriles in comparison to free cells. It is expected that more focus in future will be on purification, characterization, cloning, expression and immobilization of nitrile metabolizing

  8. Chemical composition, antimicrobial and antibiofilm activity of the essential oil and methanol extract of the Mediterranean cypress (Cupressus sempervirens L.)

    PubMed Central

    2014-01-01

    Background Cupressus sempervirens is a medicinal plant traditional, its dried leaves are used in treatment of stomach pain, diabetes, inflammation, toothache, laryngitis and as contraceptive. Methods The present study was conducted to evaluate the in vitro antimicrobial, antibiofilm and determination chemical contents of the essential oil (Eo) and methanol extract from Mediterranean C. sempervirens L. The chemical composition of a hydrodistilled Eo of C. sempervirens was analyzed by a GC and GC/MS system. Results A total of 20 constituents representing 98.1% of the oil were identified: α-pinene (48.6%), δ-3-carene (22.1%), limonene (4.6%) and α-terpinolene (4.5%) were the main components comprising 79.8% of the oil. The antimicrobial test results showed that the methanol extract of C. sempervirens strongly inhibited the growth of the test bacteria studied, except for yeast species while the Eo had moderate antibacterial, but no anti-candida activity. Klebsiella pneumoniae was proven to be the most susceptible against methanol extract. The exposure time of Eo and methanol extract for complete inhibition of cell viability of K. pneumoniae was found to be 250 μg at 30 min and 500 μg at 120 min, respectively. The antibiofilm potential of the samples was evaluated using methods of PVC microtiter and eradication on biomaterial. Visual results showed visible biofilm eradication from the surface of intravenous infusion tube at 500 μg of Eo and methanol extract. Conclusions The results presented here may suggest that the Eo and extracts of C. sempervirens possess antimicrobial and antibiofilm properties, and therefore, can be used as natural preservative ingredients in food and/or pharmaceuticals. PMID:24890383

  9. [Invasive yeast infections in neutropenic patients].

    PubMed

    Ruiz Camps, Isabel; Jarque, Isidro

    2016-01-01

    Invasive fungal diseases caused by yeasts still play an important role in the morbidity and mortality in neutropenic patients with haematological malignancies. Although the overall incidence of invasive candidiasis has decreased due to widespread use of antifungal prophylaxis, the incidence of non-Candida albicans Candida species is increasing compared with that of C.albicans, and mortality of invasive candidiasis continues to be high. In addition, there has been an increase in invasive infections caused by an array of uncommon yeasts, including species of the genus Malassezia, Rhodotorula, Trichosporon and Saprochaete, characterised by their resistance to echinocandins and poor prognosis.

  10. Yeasts in spa establishments.

    PubMed

    Svorcová, L

    1982-05-01

    It was investigated occurrence of yeasts on bathsurfaces, in sauna rooms, in swimming and therapeutic pool water. The number of yeasts decreased depending on patients age, if the rooms were furnished with bath. The lowest contamination was found after bath of 40-60 years-old women. In the saunas were yeasts not found on the upper benches with temperature above 55 degrees C. Much higher counts on lower benches and wood mats with temperature 35-40 degrees C, on basin walls and bottom-up to 10(4)-10(6)/100 cm2. It was isolated 172 yeast strains. The occurrence of some selected strains is given in Table 7, with the toxic effect of disinfectants. The most strains were resistant to Peracetic acid and Chloramin B. Since most of the isolated and determinated strains were found in contaminated environment or during various diseases, the yeasts of the genus Cryptococcus, Candida, Rhodotorula, Torulopsis and Metschnikowia should not occur in bath establishment, and should be classified among indicators of contamination of environment including water. PMID:7124167

  11. [Characteristic of the yeast isolated from patients with leukaemia].

    PubMed

    Fedorovskaia, E A; Rybal'skaia, A P; Skachkova, N K; Mel'nik, E A; Nemirovskaia, L N; Nagornaia, S S; Babich, T V; Polishchuk, L V

    2008-01-01

    It has been shown that biotopes of upper respiratory system and intestine were contaminated with yeast in 44.6% of patients with leukaemia (of 112 examined ones). Their quantity exceeds the boundary value for practically healthy people and is > or = 10(2) KOE/ml in the nasal activity and fauces and < or = 10(4) KOE/g in the intestine. It was established that in patients with leucemia the mycotic complications are mainly caused by anamorphous yeast of ascomycetic affinity. Candida albicans, as well as C. glabrata, C. rugosa and Candida sp. play the leading role. The Candida genus species are mainly sensitive to amphotericine B, clotrisamol and nistatin.

  12. Antimicrobial activity of some Pacific Northwest woods against anaerobic bacteria and yeast.

    PubMed

    Johnston, W H; Karchesy, J J; Constantine, G H; Craig, A M

    2001-11-01

    Extracts of woods commonly used for animal bedding were tested for antimicrobial activity. Essential oils from Alaska cedar (Chamaecyparis nootkatensis), western juniper (Juniperus occidentalis) and old growth Douglas fir (Pseudotsuga menziesii) as well as methanol extracts of wood from these trees plus western red cedar (Thuja plicata) and ponderosa pine (Pinus ponderosa) were tested for antimicrobial activity against anaerobic bacteria and yeast. The test microbes included Fusobacterium necrophorum, Clostridium perfringens, Actinomyces bovis and Candida albicans which are common to foot diseases and other infections in animals. The essential oils and methanol extracts were tested using a standardized broth assay. Only extracts of Alaska cedar and western juniper showed significant antimicrobial activity against each of the microbes tested. The essential oil of Douglas fir did show antimicrobial activity against A. bovis at the concentrations tested. The methanol extracts of the heartwood of Douglas fir and the sapwood of ponderosa pine showed no antimicrobial activity. The major chemical components of western juniper (cedrol and alpha- and beta-cedrene) and Alaska cedar (nootkatin) were also tested. In western juniper, alpha- and beta-cedrene were found to be active components. Nootkatin showed activity only against C. albicans. The inhibitory activity in Alaska cedar oil was high enough to justify further efforts to define the other chemical components responsible for the antimicrobial activity. PMID:11746838

  13. Antifungal suscepitibility profile of candida spp. oral isolates obtained from denture wearers

    PubMed Central

    Lyon, J.P.; Moreira, L.M.; Cardoso, M.A.G.; Saade, J.; Resende, M.A.

    2008-01-01

    Denture stomatitis is an inflammatory condition that occurs in denture wearers and is frequently associated with Candida yeasts. Antifungal susceptibility profiles have been extensively evaluated for candidiasis patients or immunosupressed individuals, but not for healthy Candida carriers. In the present study, fluconazole, itraconazole, voriconazole, terbinafine and 5-flucytosin were tested against 109 oral Candida spp. isolates. All antifungal agents were effective against the samples tested except for terbinafine. This work might provide epidemiological information about Candida spp. drug susceptibility in oral healthy individuals. PMID:24031286

  14. Fungal complications after Candida preservation fluid contamination in liver transplant recipients.

    PubMed

    Levesque, Eric; Paugam-Burtz, Catherine; Saliba, Faouzi; Khoy-Ear, Linda; Merle, Jean-Claude; Jung, Boris; Stecken, Laurent; Ferrandiere, Martine; Mihaila, Liliana; Botterel, Francoise

    2015-11-01

    Donor-derived fungal infections can be associated with severe complications in transplant recipients. Donor-derived candidiasis has been described in kidney transplant recipients where contamination of the preservation fluid (PF) was a commonly proposed source. In liver transplantation, these fungal infections have been less explored. The aim of this study was therefore to determine the incidence and clinical relevance of Candida contamination of preservation fluid in the context of liver transplantation. A 5-year (2008-2012) retrospective multicentre study involving six French liver transplantation centers was performed to determine the incidence of Candida PF contamination. Postoperative clinical features, outcomes in recipients, and risk factors for Candida-related complications of liver transplantation were studied. Candida sp. was isolated from 28 of 2107 preservation fluid samples (1.33%). Candida albicans was the most common yeast (n = 18, 64%). Twenty-two recipients (78.5%) received antifungal therapy (echinocandins in 68%) for 7-37 days. Eight patients developed yeast-related complications (28.6%) including hepatic artery aneurysms (n = 6) and Candida peritonitis (n = 2). The 1-year mortality rate among patients after a yeast-related complication was 62.5%. The incidence of Candida PF contamination was low, but was associated with dramatic postoperative complications and high mortality. Close radiological follow-up may enable early recognition of the arterial complications associated with PF contamination by Candida.

  15. Occurrence of Candida orthopsilosis in Brazilian tomato fruits (Lycopersicum esculentum Mill.)

    PubMed Central

    Robl, D.; Thimoteo, S.S.; de Souza, G.C.C.F.; Beux, M.R.; Dalzoto, P.R.; Pinheiro, R.L.; Pimentel, I.C.

    2014-01-01

    We aimed to isolate and identify yeasts found in the tomato fruit in order to obtain isolates with biotechnological potential, such as in control of fungal diseases that damage postharvest fruits. We identified Candida orthopsilosis strains LT18 and LT24. This is the first report of this yeast on Lycopersicum esculentum fruits in Brazil. PMID:24948920

  16. Laser induced breakdown spectroscopy for the discrimination of Candida strains.

    PubMed

    Manzoor, S; Ugena, L; Tornero-Lopéz, J; Martín, H; Molina, M; Camacho, J J; Cáceres, J O

    2016-08-01

    The present study reports the evaluation of Laser Induced Breakdown Spectroscopy (LIBS) and Neural Networks (NN) for the discrimination of different strains of various species of Candida. This genus of yeast was selected due to its medical relevance as it is commonly found in cases of fungal infection in humans. Twenty one strains belonging to seven species of Candida were included in the study. Scanning Electron Microscopy with Energy-Dispersive X-ray Spectroscopy (SEM-EDS) was employed as a complementary technique to provide information about elemental composition of Candida cells. The use of LIBS spectra in combination with optimized NN models provided reliable discrimination among the distinct Candida strains with a high spectral correlation index for the samples analyzed, without any false positive or false negative. Therefore, this study indicates that LIBS-NN based methodology has the potential to be used as fast fungal identification or even diagnostic method.

  17. 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.

  18. The differences in the isoelectric points of biofilm-positive and biofilm-negative Candida parapsilosis strains.

    PubMed

    Ruzicka, Filip; Horka, Marie; Hola, Veronika; Kubesova, Anna; Pavlik, Tomas; Votava, Miroslav

    2010-03-01

    The isoelectric points of 39 Candida parapsilosis strains were determined by means of capillary isoelectric focusing. The value of the isoelectric point corresponded well with cell surface hydrophobicity, as well as with the ability to form biofilm in these yeasts.

  19. Enhancement of antimycotic activity of amphotericin B by targeting the oxidative stress response of Candida and Cryptococcus with natural dihydroxybenzaldehydes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Many yeast pathogens of humans have become resistant to currently available drugs. Certain types of compounds can increase efficacy of antimycotic drugs through a process termed chemosensitization. Chemosensitizing efficacy was determined in Candida albicans, C. krusei, C. tropicalis and Cryptococcu...

  20. [Is Candida septicemia in premature infants a nosocomial infection?].

    PubMed

    Laskus, A; Mendling, W; Runge, K; Schmidt, A

    1998-01-01

    Yeast colonization of the vagina is found in about 30% of all pregnant women. Premature infants are severely endangered by generalized fungal infections due to their immature immune system. The objective of this study was to elucidate the relationship between vaginal yeast colonization of the mothers and Candida septicemia in their premature babies. In a prospective study, running from 12/1994 to 8/1996, 176 mothers, facing probable premature birth, were investigated, when hospitalized, for vaginal yeast colonization. 150 premature infants (birth weights ranging from 550 to 2390 g) of these mothers were culturally examined for yeasts in specimens from the mouth, ear, stool and urine immediately after birth as well as once weekly in the following weeks. The patients were divided into two groups. In group A, oral prophylaxis with nystatin was practiced only in infants with at least one positive yeast culture. In group B, all patients received nystatin prophylaxis. Candida septicemia developed one or two weeks after birth mainly in infants with birth weights below 1000 g. Primary oral prophylaxis with nystatin lowers considerably the risk of developing Candida infection.

  1. Candida dubliniensis at a cancer center.

    PubMed

    Sebti, A; Kiehn, T E; Perlin, D; Chaturvedi, V; Wong, M; Doney, A; Park, S; Sepkowitz, K A

    2001-04-01

    Candida dubliniensis, a germ tube-positive yeast first described and identified as a cause of oral candidiasis in patients with acquired immunodeficiency syndrome in Europe in 1995, has an expanding clinical and geographic distribution that appears to be similar to that of the other germ tube-positive yeast, Candida albicans. This study determined the frequency, clinical spectrum, drug susceptibility profile, and suitable methods for identification of this emerging pathogen at a cancer center in 1998 and 1999. Twenty-two isolates were recovered from 16 patients with solid-organ or hematologic malignancies or acquired immunodeficiency syndrome. Two patients with cancer had invasive infection, and 14 were colonized with fungus or had superficial fungal infection. All isolates produced germ tubes and chlamydospores at 37 degrees C, did not grow at 45 degrees C, and gave negative reactions with d-xylose and alpha-methyl-d-glucoside in the API 20 C AUX and ID 32 C yeast identification systems. Phenotypic identification was confirmed by molecular beacon probe technology. All isolates were susceptible to the antifungal drugs amphotericin B, 5-fluorocytosine, fluconazole, itraconazole, and ketoconazole.

  2. Uncommon opportunistic yeast bloodstream infections from Qatar.

    PubMed

    Taj-Aldeen, Saad J; AbdulWahab, Atqah; Kolecka, Anna; Deshmukh, Anand; Meis, Jacques F; Boekhout, Teun

    2014-07-01

    Eleven uncommon yeast species that are associated with high mortality rates irrespective of antifungal therapy were isolated from 17/187 (201 episodes) pediatric and elderly patients with fungemia from Qatar. The samples were taken over a 6-year period (January 2004-December 2010). Isolated species included Kluyveromyces marxianus, Lodderomyces elongisporus, Lindnera fabianii, Candida dubliniensis, Meyerozyma guilliermondii, Candida intermedia, Pichia kudriavzevii, Yarrowia lipolytica, Clavispora lusitaniae, Candida pararugosa, and Wickerhamomyces anomalus. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry provided correct identifications compared with molecular analysis testing of the same isolates. Low minimal inhibitory concentrations were found when isavuconazole and voriconazole were used for all uncommon yeast species evaluated in this study. Resistance to antifungal drugs was low and remained restricted to a few species. PMID:24934803

  3. [Methanol metabolism in plants].

    PubMed

    Stepanov, S S; Zolotar'ova, O K

    2011-01-01

    Methabolism of methanol in plant organisms is considered in the paper. Enzymes of consecutive oxidation of methanol and enzymes responsible for incorporation of carbon from methanol molecule to methyl groups of phospholipids, carboxylic acids and carbohydrates have been described. The peculiarity of plant organisms is in interaction of reactions of methanol transformation with pathways of photorespiration and C1-metabolism and in the capacity to use methanol carbon to form organic matter through photosynthesis. The inclusion of methanol metabolites in anabolic processes occurs at the level of formaldehyde and formiate. As a result, exogenous methanol at low concentrations can stimulate the photosynthetic efficiency of plants.

  4. Malassezia and Candida infections in bull terriers with lethal acrodermatitis.

    PubMed

    McEwan, N A

    2001-06-01

    In 12 cases of lethal acrodermatitis (LAD), four sampling techniques (brush, swab, scrape and adhesive tape strip) were used to study the distribution of yeasts in various body sites and these results were compared with those from five cases of atopic dermatitis and those of 10 normal dogs. Malassezia was frequently isolated from lesional and non-lesional skin and haircoat, footpads, nails and mucous membranes from dogs with either LAD or atopic dermatitis, although, generally, more Malassezia organisms were isolated from LAD cases. In normal dogs, Malassezia was most frequently recovered from the ear canal and the perianal skin. Candida was isolated frequently from dogs with LAD, but only a single isolate of this yeast was found in the other two groups. Fungal hyphae and pseudohyphae, probably Candida albicans, could be detected in samples collected from the nails and footpads of dogs with LAD. Both Malassezia and Candida could be isolated using all four sampling techniques. The MacKenzie (toothbrush) technique and adhesive tape strip cultures proved simple methods for the semiquantitative evaluation of yeasts. The high recovery rate of Malassezia and Candida from dogs with LAD is probably related to immune dysfunction, particularly T-cell dysfunction, known to be present in these dogs. C albicans infection may in part be responsible for the pathogenic changes of the nails and footpads commonly seen in cases of LAD. PMID:11440398

  5. Malassezia and Candida infections in bull terriers with lethal acrodermatitis.

    PubMed

    McEwan, N A

    2001-06-01

    In 12 cases of lethal acrodermatitis (LAD), four sampling techniques (brush, swab, scrape and adhesive tape strip) were used to study the distribution of yeasts in various body sites and these results were compared with those from five cases of atopic dermatitis and those of 10 normal dogs. Malassezia was frequently isolated from lesional and non-lesional skin and haircoat, footpads, nails and mucous membranes from dogs with either LAD or atopic dermatitis, although, generally, more Malassezia organisms were isolated from LAD cases. In normal dogs, Malassezia was most frequently recovered from the ear canal and the perianal skin. Candida was isolated frequently from dogs with LAD, but only a single isolate of this yeast was found in the other two groups. Fungal hyphae and pseudohyphae, probably Candida albicans, could be detected in samples collected from the nails and footpads of dogs with LAD. Both Malassezia and Candida could be isolated using all four sampling techniques. The MacKenzie (toothbrush) technique and adhesive tape strip cultures proved simple methods for the semiquantitative evaluation of yeasts. The high recovery rate of Malassezia and Candida from dogs with LAD is probably related to immune dysfunction, particularly T-cell dysfunction, known to be present in these dogs. C albicans infection may in part be responsible for the pathogenic changes of the nails and footpads commonly seen in cases of LAD.

  6. 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.

  7. 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. PMID:16954270

  8. Evaluation of CHROM-Pal medium for the isolation and direct identification of Candida dubliniensis in primary cultures from the oral cavity.

    PubMed

    Sahand, Ismail H; Maza, José L; Eraso, Elena; Montejo, Miguel; Moragues, María D; Aguirre, José M; Quindós, Guillermo; Pontón, José

    2009-11-01

    Candida albicans is the species most frequently isolated from oral specimens, but the recovery of other Candida species such as Candida dubliniensis is increasing. Differentiation of C. dubliniensis from C. albicans requires special tests and both species are misidentified in some studies. CHROM-Pal (CH-P) is a novel chromogenic medium used in our laboratory for differentiation between C. albicans and C. dubliniensis on the basis of colony colour and morphology, and chlamydospore production. The performance of CH-P and CHROMagar Candida (CAC) was compared for primary isolation and presumptive identification of yeasts from oral specimens from human immunodeficiency virus (HIV)-infected and uninfected individuals. The identification of Candida species on both media was compared with two reference identification methods (API ID 32 C and multiplex PCR). A total of 137/205 oral swabs (66.8 %) plated onto CH-P and CAC media were positive by culture and resulted in the growth of 171 isolates of Candida species on CH-P, whilst only 159 isolates grew on CAC. C. albicans was the most frequently isolated species in both groups of patients, followed by Candida parapsilosis in the HIV-negative group, and by C. dubliniensis in the HIV-infected group. The other Candida species isolated were Candida guilliermondii, Candida glabrata, Candida krusei, Candida tropicalis, Candida famata, Candida rugosa, Candida kefyr, Candida pelliculosa and Candida pulcherrima. The sensitivity and specificity for identifying C. albicans, C. krusei, C. tropicalis and C. dubliniensis on CH-P were over 98.5 %, always equal to or higher than those obtained when CAC was used. CH-P is a simple reliable medium for primary isolation and presumptive identification of yeast isolates from oral samples. The ability of CH-P to discriminate between C. dubliniensis and C. albicans was significantly higher (P <0.05) than that of CAC.

  9. Melittin induces apoptotic features in Candida albicans

    SciTech Connect

    Park, Cana; Lee, Dong Gun

    2010-03-26

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

  10. 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.

  11. Candida Infective Endocarditis

    PubMed Central

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

    2009-01-01

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

  12. Candida infective endocarditis.

    PubMed

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

    2008-07-01

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

  13. Multicenter Evaluation of Candida QuickFISH BC for Identification of Candida Species Directly from Blood Culture Bottles

    PubMed Central

    Abdelhamed, Ayman M.; Zhang, Sean X.; Watkins, Tonya; Morgan, Margie A.; Wu, Fann; Buckner, Rebecca J.; Fuller, DeAnna D.; Davis, Thomas E.; Salimnia, Hossein; Fairfax, Marilynn R.; Lephart, Paul R.; Poulter, Melinda D.; Regi, Sarah B.

    2015-01-01

    Candida species are common causes of bloodstream infections (BSI), with high mortality. Four species cause >90% of Candida BSI: C. albicans, C. glabrata, C. parapsilosis, and C. tropicalis. Differentiation of Candida spp. is important because of differences in virulence and antimicrobial susceptibility. Candida QuickFISH BC, a multicolor, qualitative nucleic acid hybridization assay for the identification of C. albicans (green fluorescence), C. glabrata (red fluorescence), and C. parapsilosis (yellow fluorescence), was tested on Bactec and BacT/Alert blood culture bottles which signaled positive on automated blood culture devices and were positive for yeast by Gram stain at seven study sites. The results were compared to conventional identification. A total of 419 yeast-positive blood culture bottles were studied, consisting of 258 clinical samples (89 C. glabrata, 79 C. albicans, 23 C. parapsilosis, 18 C. tropicalis, and 49 other species) and 161 contrived samples inoculated with clinical isolates (40 C. glabrata, 46 C. albicans, 36 C. parapsilosis, 19 C. tropicalis, and 20 other species). A total of 415 samples contained a single fungal species, with C. glabrata (n = 129; 30.8%) being the most common isolate, followed by C. albicans (n = 125; 29.8%), C. parapsilosis (n = 59; 14.1%), C. tropicalis (n = 37; 8.8%), and C. krusei (n = 17; 4.1%). The overall agreement (with range for the three major Candida species) between the two methods was 99.3% (98.3 to 100%), with a sensitivity of 99.7% (98.3 to 100%) and a specificity of 98.0% (99.4 to 100%). This study showed that Candida QuickFISH BC is a rapid and accurate method for identifying C. albicans, C. glabrata, and C. parapsilosis, the three most common Candida species causing BSI, directly from blood culture bottles. PMID:25762766

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

    PubMed Central

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

    2016-01-01

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

  15. Yeast community survey in the Tagus estuary.

    PubMed

    de Almeida, João M G C F

    2005-07-01

    The yeast community in the waters of the Tagus estuary, Portugal, was followed for over a year in order to assess its dynamics. Yeast occurrence and incidence were measured and this information was related to relevant environmental data. Yeast occurrence did not seem to depend upon tides, but river discharge had a dramatic impact both on the density and diversity of the community. The occurrence of some yeasts was partially correlated with faecal pollution indicators. Yeast isolates were characterized by microsatellite primed PCR (MSP-PCR) fingerprinting and rRNA gene sequencing. The principal species found were Candida catenulata, C. intermedia, C. parapsilosis, Clavispora lusitaniae, Debaryomyces hansenii, Pichia guilliermondii, Rhodotorula mucilaginosa and Rhodosporidium diobovatum. The incidence of these species was evaluated against the environmental context of the samples and the current knowledge about the substrates from which they are usually isolated. PMID:16329949

  16. Cloning and expression of Candida guilliermondii xylose reductase gene (xyl1) in Pichia pastoris.

    PubMed

    Handumrongkul, C; Ma, D P; Silva, J L

    1998-04-01

    A xylose reductase gene (xyl1) of Candida guilliermondii ATCC 20118 was cloned and characterized. The open reading frame of xyl1 contained 954 nucleotides encoding a protein of 317 amino acids with a predicted molecular mass of 36 kDa. The derived amino acid sequence of C. guilliermondii xylose reductase was 70.4% homologous to that of Pichia stipitis. The gene was placed under the control of an alcohol oxidase promoter (AOX1) and integrated into the genome of a methylotrophic yeast, Pichia pastoris. Methanol induced the expression of the 36-kDa xylose reductase in both intracellular and secreted expression systems. The expressed enzyme preferentially utilized NADPH as a cofactor and was functional both in vitro and in vivo. The different cofactor specificity between P. pastoris and C. guilliermondii xylose reductases might be due to the difference in the numbers of histidine residues and their locations between the two proteins. The recombinant was able to ferment xylose, and the maximum xylitol accumulation (7.8 g/l) was observed when the organism was grown under aerobic conditions. PMID:9615481

  17. Acid Lipase from Candida viswanathii: Production, Biochemical Properties, and Potential Application

    PubMed Central

    de Almeida, Alex Fernando; Carmona, Eleonora Cano

    2013-01-01

    Influences of environmental variables and emulsifiers on lipase production of a Candida viswanathii strain were investigated. The highest lipase activity (101.1 U) was observed at 210 rpm, pH 6.0, and 27.5°C. Other fermentation parameters analyzed showed considerable rates of biomass yield (YL/S = 1.381 g/g), lipase yield (YL/S = 6.892 U/g), and biomass productivity (PX = 0.282 g/h). Addition of soybean lecithin increased lipase production in 1.45-fold, presenting lipase yield (YL/S) of 10.061 U/g. Crude lipase presented optimal activity at acid pH of 3.5, suggesting a new lipolytic enzyme for this genus and yeast in general. In addition, crude lipase presented high stability in acid conditions and temperature between 40 and 45°C, after 24 h of incubation in these temperatures. Lipase remained active in the presence of organic solvents maintaining above 80% activity in DMSO, methanol, acetonitrile, ethanol, acetone, 1-propanol, isopropanol, and 2-propanol. Effectiveness for the hydrolysis of a wide range of natural triglycerides suggests that this new acid lipase has high potential application in the oleochemical and food industries for hydrolysis and/or modification of triacylglycerols to improve the nutritional properties. PMID:24350270

  18. Acid lipase from Candida viswanathii: production, biochemical properties, and potential application.

    PubMed

    de Almeida, Alex Fernando; Tauk-Tornisielo, Sâmia Maria; Carmona, Eleonora Cano

    2013-01-01

    Influences of environmental variables and emulsifiers on lipase production of a Candida viswanathii strain were investigated. The highest lipase activity (101.1 U) was observed at 210 rpm, pH 6.0, and 27.5°C. Other fermentation parameters analyzed showed considerable rates of biomass yield (Y L/S = 1.381 g/g), lipase yield (Y L/S = 6.892 U/g), and biomass productivity (P X = 0.282 g/h). Addition of soybean lecithin increased lipase production in 1.45-fold, presenting lipase yield (Y L/S ) of 10.061 U/g. Crude lipase presented optimal activity at acid pH of 3.5, suggesting a new lipolytic enzyme for this genus and yeast in general. In addition, crude lipase presented high stability in acid conditions and temperature between 40 and 45°C, after 24 h of incubation in these temperatures. Lipase remained active in the presence of organic solvents maintaining above 80% activity in DMSO, methanol, acetonitrile, ethanol, acetone, 1-propanol, isopropanol, and 2-propanol. Effectiveness for the hydrolysis of a wide range of natural triglycerides suggests that this new acid lipase has high potential application in the oleochemical and food industries for hydrolysis and/or modification of triacylglycerols to improve the nutritional properties. PMID:24350270

  19. Acid lipase from Candida viswanathii: production, biochemical properties, and potential application.

    PubMed

    de Almeida, Alex Fernando; Tauk-Tornisielo, Sâmia Maria; Carmona, Eleonora Cano

    2013-01-01

    Influences of environmental variables and emulsifiers on lipase production of a Candida viswanathii strain were investigated. The highest lipase activity (101.1 U) was observed at 210 rpm, pH 6.0, and 27.5°C. Other fermentation parameters analyzed showed considerable rates of biomass yield (Y L/S = 1.381 g/g), lipase yield (Y L/S = 6.892 U/g), and biomass productivity (P X = 0.282 g/h). Addition of soybean lecithin increased lipase production in 1.45-fold, presenting lipase yield (Y L/S ) of 10.061 U/g. Crude lipase presented optimal activity at acid pH of 3.5, suggesting a new lipolytic enzyme for this genus and yeast in general. In addition, crude lipase presented high stability in acid conditions and temperature between 40 and 45°C, after 24 h of incubation in these temperatures. Lipase remained active in the presence of organic solvents maintaining above 80% activity in DMSO, methanol, acetonitrile, ethanol, acetone, 1-propanol, isopropanol, and 2-propanol. Effectiveness for the hydrolysis of a wide range of natural triglycerides suggests that this new acid lipase has high potential application in the oleochemical and food industries for hydrolysis and/or modification of triacylglycerols to improve the nutritional properties.

  20. Oral Candida isolates colonizing or infecting human immunodeficiency virus-infected and healthy persons in Mexico.

    PubMed

    Sánchez-Vargas, Luis Octavio; Ortiz-López, Natalia Guadalupe; Villar, María; Moragues, María Dolores; Aguirre, José Manuel; Cashat-Cruz, Miguel; Lopez-Ribot, Jose Luis; Gaitán-Cepeda, Luis Alberto; Quindós, Guillermo

    2005-08-01

    Oral yeast carriage was studied in 312 Mexican subjects. Candida albicans was the most frequent species, but other Candida spp. were isolated from 16.5 to 38.5% of patients. Colonization did not correlate with CD4+ number or viral load, but highly active antiretroviral therapy reduced the frequency of candidiasis. Most isolates were susceptible to fluconazole, but 10.8% were resistant to one or more azoles.

  1. Yeasts in an industrial malting ecosystem.

    PubMed

    Laitila, A; Wilhelmson, A; Kotaviita, E; Olkku, J; Home, S; Juvonen, R

    2006-11-01

    The malting ecosystem consists of two components: the germinating cereal grains and the complex microbial community. Yeasts and yeast-like fungi are an important part of this ecosystem, but the composition and the effects of this microbial group have been largely unknown. In this study we surveyed the development of yeasts and yeast-like fungi in four industrial scale malting processes. A total of 136 malting process samples were collected and examined for the presence of yeasts growing at 15, 25 and 37 degrees C. More than 700 colonies were isolated and characterized. The isolates were discriminated by PCR-fingerprinting with microsatellite primer (M13). Yeasts representing different fingerprint types were identified by sequence analysis of the D1/D2 domain of the 26S rRNA gene. Furthermore, identified yeasts were screened for the production of alpha-amylase, beta-glucanase, cellulase and xylanase. A numerous and diverse yeast community consisting of both ascomycetous (25) and basidiomycetous (18) species was detected in the various stages of the malting process. The most frequently isolated ascomycetous yeasts belonged to the genera Candida, Clavispora, Galactomyces, Hanseniaspora, Issatchenkia, Pichia, Saccharomyces and Williopsis and the basidiomycetous yeasts to Bulleromyces, Filobasidium, Cryptococcus, Rhodotorula, Sporobolomyces and Trichosporon. In addition, two ascomycetous yeast-like fungi (black yeasts) belonging to the genera Aureobasidium and Exophiala were commonly detected. Yeasts and yeast-like fungi produced extracellular hydrolytic enzymes with a potentially positive contribution to the malt enzyme spectrum. Knowledge of the microbial diversity provides a basis for microflora management and understanding of the role of microbes in the cereal germination process. PMID:16758169

  2. Killer yeasts inhibit the growth of the phytopathogen Moniliophthora perniciosa, the causal agent of Witches' Broom disease.

    PubMed

    de Souza Cabral, Anderson; de Carvalho, Patricia Maria Barroso; Pinotti, Tatiana; Hagler, Allen Norton; Mendonça-Hagler, Leda Cristina Santana; Macrae, Andrew

    2009-01-01

    Fruit and soil yeasts isolated from the Amazon, Atlantic Rainforests and an organic farm were screened for killer activity against yeasts. Killer yeasts were then tested against the phytopathogen Moniliophthora perniciosa (syn. Crinipellis perniciosa) and a Dipodascus capitatus strain and a Candida sp strain inhibited its growth.

  3. ISOLATION OF THE CANDIDA TROPICALIS GENE FOR P450 LANOSTEROL DEMETHYLASE AND ITS EXPRESSION IN SACCAROMYCES CEREVISIAE

    EPA Science Inventory

    We have isolated the gene for cytochrome P450 lanosterol 14-demethylase (14DM) from the yeast Candida tropicalis. This was accomplished by screening genomic libraries of strain ATCC750 in E. coli using a DNA fragment containing the yeast Saccharomyces cerevisiae 14DM gene. Identi...

  4. [Vertical transmission of Candida and its consequences].

    PubMed

    Blaschke-Hellmessen, R

    1998-01-01

    The subpartal transmission of Candida albicans from the vagina of the mother to the newborn is an old and often discussed problem. Thereby the decrease of the infection rate and the prevention of systemic mycoses due to Candida--especially in newborns of risk--are the main objectives. At the end of pregnancy C. albicans is found in vaginal secretions in 25-30% of the women. 70-85% of these women subpartally contaminate their infants with this yeast. Thus 22-24% of all infants acquire C. albicans sub partus. From this situation the following conclusions may be drawn: 1. A prepartal prophylaxis for mycoses in pregnant women with vaginal Candida colonization is to obtain by an intravaginal treatment with polyene or azole antimycotics at the end of pregnancy. Recommendations are offered. 2. A prophylaxis for mycoses in newborns which are especially disposed for systemic candidosis by several factors of risk is to initiate. The oral application of polyene antimycoticas during the considerable endangering by mycoses has been proved to be useful. Referring to this recommendations are offered.

  5. Effect of Marine Polyunsaturated Fatty Acids on Biofilm Formation of Candida albicans and Candida dubliniensis

    PubMed Central

    Thibane, Vuyisile S.; Kock, Johan L. F.; Ells, Ruan; van Wyk, Pieter W. J.; Pohl, Carolina H.

    2010-01-01

    The effect of marine polyunsaturated fatty acids on biofilm formation by the human pathogens Candida albicans and Candida dubliniensis was investigated. It was found that stearidonic acid (18:4 n-3), eicosapentaenoic acid (20:5 n-3), docosapentaenoic acid (22:5 n-3) and docosahexaenoic acid (22:6 n-3) have an inhibitory effect on mitochondrial metabolism of both C. albicans and C. dubliniensis and that the production of biofilm biomass by C. dubliniensis was more susceptible to these fatty acids than C. albicans. Ultrastructural differences, which may be due to increased oxidative stress, were observed between treated and untreated cells of C. albicans and C. dubliniensis with formation of rough cell walls by both species and fibrillar structures in C. dubliniensis. These results indicate that marine polyunsaturated fatty acids may be useful in the treatment and/or prevention of biofilms formed by these pathogenic yeasts. PMID:21116408

  6. Extracellular Proteinases of Yeasts and Yeastlike Fungi1

    PubMed Central

    Ahearn, D. G.; Meyers, S. P.; Nichols, R. A.

    1968-01-01

    Approximately 800 yeasts and other fungi, representing over 70 species, were tested for extracellular caseinolysis. Isolates of a variety of genera, including Aureobasidium, Cephalosporium, Endomycopsis, Kluyveromyces, and numerous sporobolomycetes, demonstrated significant proteolytic activity. Caseinolysis was not necessarily correlated with gelatin liquefaction or with albuminolysis. Numerous fungi showed significant proteolysis at 5 C. The most active organisms were isolates of Candida lipolytica, Aureobasidium pullulans, Candida punicea, and species of Cephalosporium. Taxonomic and ecological implications of proteolytic activity are discussed. Images Fig. 1 PMID:5692110

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

    PubMed

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

    2011-10-01

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

  8. Inhibitory effect of coated mannan against the adhesion of Candida biofilms to denture base resin.

    PubMed

    Sato, Maki; Ohshima, Tomoko; Maeda, Nobuko; Ohkubo, Chikahiro

    2013-01-01

    The adherence of Candida on dentures is related to diseases such as denture stomatitis and aspiration pneumonia. Mannan is a major component of the Candida cell surface, and contributes to the cell adherence. A previous report indicated that the adherence of C. albicans to culture dishes was inhibited by the coating them with mannan. The purpose of this study was to examine the adhesion inhibitory effect of mannan coating on acrylic denture surfaces against C. albicans and C. glabrata. The amount of Candida attached on the acrylic surfaces coated with mannan was calibrated by culture methods. Mannan showed significant inhibitory effects on Candida adhesion in both the yeast and hyphal form in a concentration-dependent manner, and the durability of the inhibitory effect continued for three days. These results suggest that mannan coating on the denture base acrylic can prevent Candida adhesion on the denture.

  9. Two-stage gas-phase bioreactor for the combined removal of hydrogen sulphide, methanol and alpha-pinene.

    PubMed

    Rene, Eldon R; Jin, Yaomin; Veiga, María C; Kennes, Christian

    2009-11-01

    Biological treatment systems have emerged as cost-effective and eco-friendly techniques for treating waste gases from process industries at moderately high gas flow rates and low pollutant concentrations. In this study, we have assessed the performance of a two-stage bioreactor, namely a biotrickling filter packed with pall rings (BTF, 1st stage) and a perlite + pall ring mixed biofilter (BF, 2nd stage) operated in series, for handling a complex mixture of hydrogen sulphide (H2S), methanol (CH3OH) and alpha-pinene (C10H16). It has been reported that the presence of H2S can reduce the biofiltration efficiency of volatile organic compounds (VOCs) when both are present in the gas mixture. Hydrogen sulphide and methanol were removed in the first stage BTF, previously inoculated with H2S-adapted populations and a culture containing Candida boidinii, an acid-tolerant yeast, whereas, in the second stage, alpha-pinene was removed predominantly by the fungus Ophiostoma stenoceras. Experiments were conducted in five different phases, corresponding to inlet loading rates varying between 2.1 and 93.5 g m(-3) h(-1) for H2S, 55.3 and 1260.2 g m(-3) h(-1) for methanol, and 2.8 and 161.1 g m(-3) h(-1) for alpha-pinene. Empty bed residence times were varied between 83.4 and 10 s in the first stage and 146.4 and 17.6 s in the second stage. The BTF, working at a pH as low as 2.7 as a result of H2S degradation, removed most of the H2S and methanol but only very little alpha-pinene. On the other hand, the BF, at a pH around 6.0, removed the rest of the H2S, the non-degraded methanol and most of the alpha-pinene vapours. Attempts were originally made to remove the three pollutants in a single acidophilic bioreactor, but the Ophiostoma strain was hardly active at pH <4. The maximum elimination capacities (ECs) reached by the two-stage bioreactor for individual pollutants were 894.4 g m(-3) h(-1) for methanol, 45.1 g m(-3) h(-1) for H2S and 138.1 g m(-3) h(-1) for alpha-pinene. The

  10. Metschnikowia noctiluminum sp. nov., Metschnikowia corniflorae sp. nov., and Candida chrysomelidarum sp. nov., isolated from green lacewings and beetles.

    PubMed

    Nguyen, Nhu H; Suh, Sung-Oui; Erbil, Cennet K; Blackwell, Meredith

    2006-03-01

    Fourteen yeast isolates belonging to the Metschnikowia clade were isolated from the digestive tracts of lacewings (Neuroptera: Chrysopidae), soldier beetles and leaf beetles (Coleoptera: Cantharidae and Chrysomelidae), and a caddisfly (Trichoptera: Hydropsychidae). The insect hosts were associated with sugary substances of plants, a typical habitat for yeasts in this clade. Based on DNA sequence comparisons and phenetic characters, the yeasts were identified as Candida picachoensis, Candida pimensis, and four undescribed taxa. Among the undescribed taxa, three yeasts were distinguished from one another and from other described taxa by nucleotide differences in the ribosomal DNA repeat, which were sufficient to consider them as new species. Two of the novel yeast species are described as Metschnikowia noctiluminum (NRRL Y-27753(T)) and M. cornifloraespp. nov. (NRRL Y-27750(T)) based in part on production of needle-shaped ascospores, which are found in most Metschnikowia species. Sexual reproduction was not observed in the third new yeast, Candida chrysomelidarumsp. nov. (NRRL Y-27749(T)). A fourth isolate, NRRL Y-27752, was not significantly distinct from Metschnikowia viticola and Candida kofuensis to be described as a new species. Phylogenetic analysis of the D1/D2 loop sequences placed M. noctiluminum within the M. viticola clade, while C. chrysomelidarum was a sister taxon of Candida rancensis. Metschnikowia corniflorae was phylogenetically distinct from other new species and fell outside of the large-spored Metschnikowia group.

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

    PubMed

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

    2015-10-01

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

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

    PubMed

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

    2015-10-01

    The aim of this study was to characterize the yeast microbiota of natural cavities of manatees kept in captivity in Brazil. Sterile swabs from the oral cavity, nostrils, genital opening, and rectum of 50 Trichechus inunguis and 26 Trichechus manatus were collected. The samples were plated on Sabouraud agar with chloramphenicol and incubated at 25 °C for 5 days. The yeasts isolated were phenotypically identified by biochemical and micromorphological tests. Overall, 141 strains were isolated, of which 112 were from T. inunguis (Candida albicans, Candida parapsilosis sensu stricto, Candida orthopsilosis, Candida metapsilosis, Candida guilliermondii, Candida pelliculosa, Candida tropicalis, Candida glabrata, Candida famata, Candida krusei, Candida norvegensis, Candida ciferri, Trichosporon sp., Rhodotorula sp., Cryptococcus laurentii) and 29 were from T. manatus (C. albicans, C. tropicalis, C. famata, C. guilliermondii, C. krusei, Rhodotorula sp., Rhodotorula mucilaginosa, Rhodotorula minuta, Trichosporon sp.). This was the first systematic study to investigate the importance of yeasts as components of the microbiota of sirenians, demonstrating the presence of potentially pathogenic species, which highlights the importance of maintaining adequate artificial conditions for the health of captive manatees. PMID:26308797

  13. Candida kefyr as a cause of bloodstream infection and adjunctive role of biomarkers in its diagnosis.

    PubMed

    Khan, Z; Ahmad, S; Al-Obaid, K; Joseph, L; Chandy, R

    2015-03-01

    A rare case of bloodstream infection caused by Candida kefyr is described. The diagnosis was established by repeatedly isolating the yeast in blood cultures and by detecting C. kefyr-specific DNA in serum samples. Demonstration of elevated serum levels of β-D-glucan and Candida mannan also provided additional diagnostic evidence. The identity of the isolates was confirmed by PCR sequencing of the ITS region of rDNA. This is the first report of C. kefyr candidemia from Kuwait and the Middle East. The report highlights emerging clinical significance of rare Candida spp. in etiology of candidemia and reinforces the adjunctive role of biomarkers in diagnosis.

  14. Candida infection of the skin

    MedlinePlus

    ... albicans . Candida is the most common cause of diaper rash in infants. The fungi take advantage of the warm, moist conditions inside the diaper. Candida infection is particularly common in people with ...

  15. [Molecular identification of Candida lusitaniae in lower respiratory tract infection].

    PubMed

    Espinosa, Israel Martínez; Ibarra, Misael González; Torres Guerrero, Haydee K

    2014-01-01

    Candida lusitaniae is a yeast that has emerged as a low frequency nosocomial pathogen in deep infections. Although it usually shows in vitro susceptibility to all antifungal agents, in vivo resistance to amphotericin B has been observed in several clinical cases. Therefore, its early identification in the course of therapy is important. We report the isolation of C. lusitaniae as an etiologic agent of a lower respiratory tract infection in a male patient. Urine and sputum cultures were negative for bacteria and positive for this yeast. Isolates were identified by routine phenotypic methods and confirmed by sequencing and restriction fragment length polymorphism analysis of PCR internal spacer of ribosomal DNA.

  16. An actidione resistant Candida tropicalis from custard apple juice.

    PubMed

    Onkarayya, H; Suresh, E R; Ethiraj, S

    1981-01-01

    An actidione resistant yeast, Candida tropicalis, was isolated from fermenting custard apple juice. Though a slight inhibition of growth was observed on the first day with 5000 ppm of actidione, growth was equal to control after one week. Sorbic acid at 500 ppm and above inhibited the growth of this yeast while sodium benzoate and potassium metabisulphite were unable to suppress the growth even at 1000 ppm. Fermentation and assimilation of different carbon sources were delayed in the presence of 1000 ppm of actidione suggesting the disruption of protein synthesis by actidione.

  17. Continuous fermentation of Saccharomycopsis fibuligera and Candida utilis

    SciTech Connect

    Admassu, W.; Korus, R.A.; Heinsch, R.C.

    1984-12-01

    Results are presented for the continuous, two-stage fermentation of Saccharomycopsis fibuligera and Candida utilis. The amylolytic yeast Saccharomycopsis fibuligera was grown in the first stage, and a mixed culture of the two yeasts was maintained in the second stage. The first stage was operated under constant conditions near the optimum dilution rate for amylase productivity. Maximum biomass production occurred at a second-stage dilution rate, D2, of 0.27 h/sup -1/ at a volumetric ratio (V1/V2) of 0.57. The objective of this study was to determine the effect of the volumetric ratio on this two-stage fermentation. 3 references.

  18. Clinical significance of the isolation of Candida species from hospitalized patients.

    PubMed

    Magalhães, Yankee C; Bomfim, Maria Rosa Q; Melônio, Luciane C; Ribeiro, Patrícia C S; Cosme, Lécia M; Rhoden, Cristianne R; Marques, Sirlei G

    2015-03-01

    In this study, we isolated and phenotypically identified 108 yeast strains from various clinical specimens collected from 100 hospitalized patients at three tertiary hospitals in São Luís-Maranhão, Brazil, from July to December 2010. The isolates were analyzed for their susceptibility to four of the most widely used antifungal agents in the surveyed hospitals, amphotericin B, fluconazole, 5-flucytosine and voriconazole. The species identified were Candida albicans (41.4%), Candida tropicalis (30.1%), C. glabrata (7.4%), Candida parapsilosis (5.5%), Candida krusei (4.6%), Cryptococcus neoformans (4.6%), Trichosporon spp . (3.7%), Candida norvegensis (0.9%), Rhodotorula glutinis (0.9%) and Pichia farinosa (0.9%). A higher isolation rate was observed in the following clinical specimens: urine (54 isolates; 50%), respiratory tract samples (21 isolates; 19.4%) and blood (20 isolates; 18.6%). Candida albicans isolates were 100% sensitive to all antifungal agents tested, whereas Candida krusei and Crytococcus neoformans displayed intermediate resistance to 5-flucytosine, with Minimal Inhibitory Concentration (MIC) values of 8 mg/mL and 16 mg/mL, respectively. Both strains were also S-DD to fluconazole with an MIC of 16 mg/mL. C. tropicalis was resistant to 5-flucytosine with an MIC of 32 μg/mL. This study demonstrates the importance of identifying the yeast species involved in community and nosocomial infections.

  19. Clinical significance of the isolation of Candida species from hospitalized patients

    PubMed Central

    Magalhães, Yankee C.; Bomfim, Maria Rosa Q.; Melônio, Luciane C.; Ribeiro, Patrícia C.S.; Cosme, Lécia M.; Rhoden, Cristianne R.; Marques, Sirlei G.

    2015-01-01

    In this study, we isolated and phenotypically identified 108 yeast strains from various clinical specimens collected from 100 hospitalized patients at three tertiary hospitals in São Luís-Maranhão, Brazil, from July to December 2010. The isolates were analyzed for their susceptibility to four of the most widely used antifungal agents in the surveyed hospitals, amphotericin B, fluconazole, 5-flucytosine and voriconazole. The species identified were Candida albicans (41.4%), Candida tropicalis (30.1%), C. glabrata (7.4%), Candida parapsilosis (5.5%), Candida krusei (4.6%), Cryptococcus neoformans (4.6%), Trichosporon spp . (3.7%), Candida norvegensis (0.9%), Rhodotorula glutinis (0.9%) and Pichia farinosa (0.9%). A higher isolation rate was observed in the following clinical specimens: urine (54 isolates; 50%), respiratory tract samples (21 isolates; 19.4%) and blood (20 isolates; 18.6%). Candida albicans isolates were 100% sensitive to all antifungal agents tested, whereas Candida krusei and Crytococcus neoformans displayed intermediate resistance to 5-flucytosine, with Minimal Inhibitory Concentration (MIC) values of 8 mg/mL and 16 mg/mL, respectively. Both strains were also S-DD to fluconazole with an MIC of 16 mg/mL. C. tropicalis was resistant to 5-flucytosine with an MIC of 32 μg/mL. This study demonstrates the importance of identifying the yeast species involved in community and nosocomial infections. PMID:26221096

  20. [Vaginal candida infection in the third trimester of pregnancy].

    PubMed

    Nikolov, A; Shopova, E; Mŭseva, A; Dimitrov, A

    2006-01-01

    The aim of this study is the determination of the frequency of vaginal Candida colonization in pregnant women in the third trimester, the status of the vaginal ecosystem, the grade and the subspecies of the candidal colonization, clinical manifestations and the therapeutic effect of the local antimycotic treatment. In this study it has been followed 172 pregnant women with a normal pregnancy at the end of the third trimester. It has been estimated that about 28.4% of all women get a vaginal yeast colonization - Candida spp. In 89.7% (44 women) of the cases, the colonization was caused by an overgrowth of the yeast Candida albicans. The remaining cases are caused by other subspecies of Candida - 5 cases (10.3%) - C. tropicalis /2/, C. parapsilosis /2/, C. glabrata/1/. The women in the first group were with symptoms of active candidosis (25.6%) and 88.3% of the cases were confirmed by microscopy, and 90.6% after a bacterial growth in a culture. In 7.7% of the cases was specified a mild to moderate colonization without a clinical signs of infection (II group). The local treatment with antimycotic vaginal globules and crème for 5 to 7 days alleviates the clinical symptoms. It was not observed a case of maternal - fetal transmission of this infection not a clinical manifestation in the early postpartal period. PMID:17168476

  1. Biotyping of Candida albicans: results of an international collaborative survey.

    PubMed Central

    Odds, F C; Auger, P; Krogh, P; Neely, A N; Segal, E

    1989-01-01

    An agar plate system for biotyping isolates of Candida albicans was evaluated in four laboratories for 18 coded yeast isolates, each tested in triplicate on duplicate series of agar plates. The results showed that the biotyping system gave excellent intralaboratory reproducibility. However, because the concordance of data among laboratories was poor, the method must be regarded as suitable only for research applications and not for routine use. PMID:2671015

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

    PubMed

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

    2015-09-01

    The prevention of adhesion of Candida cells to acrylic surfaces can be regarded as an alternative to prevent denture stomatitis. The use of quorum sensing molecules, such as tyrosol, could potentially interfere with the adhesion process. Therefore, the aim of this study was to assess the effect of tyrosol on adhesion of single and mixed cultures of Candida albicans and Candida glabrata to acrylic resin surfaces. Tyrosol was diluted in each yeast inoculum (10(7) cells/ml in artificial saliva) at 25, 50, 100, and 200 mM. Then, each dilution was added to wells of 24-well plates containing the acrylic specimens, and the plates were incubated at 37°C for 2 h. After, the effect of tyrosol was determined by total biomass quantification, metabolic activity of the cells and colony-forming unit counting. Chlorhexidine gluconate (CHG) was used as a positive control. Data were analyzed using analysis of variance (ANOVA) and the Holm-Sidak post hoc test (α = 0.05). The results of total biomass quantification and metabolic activity revealed that the tyrosol promoted significant reductions (ranging from 22.32 to 86.16%) on single C. albicans and mixed cultures. Moreover, tyrosol at 200 mM and CHG significantly reduced (p < 0.05) the number of adhered cells to the acrylic surface for single and mixed cultures of both species, with reductions ranging from 1.74 to 3.64-log10. In conclusion, tyrosol has an inhibitory effect on Candida adhesion to acrylic resin, and further investigations are warranted to clarify its potential against Candida infections. PMID:26162470

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

    PubMed

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

    2015-09-01

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

  4. Prevalence of Candida Species in Patients with Psoriasis.

    PubMed

    Ovčina-Kurtović, Nermina; Kasumagić-Halilović, Emina; Helppikangans, Hana; Begić, Jasmina

    2016-08-01

    Investigation of Candida yeast prevalence in patients with psoriasis has been performed with the aim of determining their possible role as a trigger factor in the pathogenic process of this disease. The purpose of our study was to investigate the prevalence of Candida species on the skin of intertriginous areas and psoriasis lesions as well as the prevalence of Candida species in the stool of patients with psoriasis. This study also examines a possible correlation between the severity of psoriasis and prevalence of isolated Candida species. The patients with psoriasis were divided into two groups according to the clinical type of psoriasis; a group with plaque psoriasis (PP) and psoriasis inversa (PI) (G1) and a group with psoriasis erythrodermica (PE) and psoriasis pustulosa (PPS) (G2). The group of patients with PP and PI (G1) was divided according to score on the Psoriasis Area Severity Index test (PASI) according to severity of disease into the clinical subgroup with PASI <50 and another subgroup with PASI >50. Mycological analysis of skin samples in patients of the clinical group with PP and PI showed a statistically significant difference as well as correlation between the results of isolated specimens of Candida species from the skin of intertriginous areas and psoriasis lesions, the clinical form of psoriasis, and the PASI score. PMID:27663922

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

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

    PubMed

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

    2014-06-01

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

  7. Standardization and demonstration of antibody-coated Candida in urine by direct immunofluorescence test.

    PubMed

    Talwar, P; Pal, S R; Kaur, P; Kaiwar, R; Jayashree, T; Rao, M S; Vaidyanathan, S; Taiwar, P

    1986-04-01

    Acetone, carbontetrachloride, ethyl alcohol, mixture of ethyl alcohol and acetone, and heat were assessed for fixative property for direct immunofluorescent (IF) staining of antibody-coated Candida cells. The results indicated that ethyl alcohol was the most suitable fixative for the test. Antisera containing 16 units of Candida albicans type A agglutinin were found essential to get optimal detectable fluorescence of antibody-coated yeast cells. IF test showed cross reactivity between the yeasts of C. albicans and C. tropicalis. However, there was no cross reactivity with the conidia of A. flavus. The direct IF test could demonstrate antibody-coated yeast cells and pseudomycelia in deposits of urine in the direct smear. It correlated well with microscopy and culture studies. At times, it could demonstrate the antibody-coated yeasts earlier than routine significant culture. It could also differentiate the significant from non-significant fungal isolates from urine.

  8. Statistical approach to study the interactive effects of process parameters for enhanced xylitol production by Candida tropicalis and its potential for the synthesis of xylitol monoesters.

    PubMed

    Misra, Swati; Raghuwanshi, Shailendra; Saxena, Rajendra Kumar

    2013-12-01

    Previous results showed that an indigenously isolated yeast strain of Candida tropicalis was found to produce 12.11 g/L of xylitol under unoptimized conditions in presence of 50 g/L of xylose. In the present study, optimizing the process using one-variable at-a-time resulted in the production of 59.07 g/L of xylitol in 96 h in presence of 100 g/L xylose. Further optimization using response surface methodology led to the production of 65.45 g/L in medium containing 100 g/L xylose, 0.5% yeast extract, 0.03% MgSO(4).7H(2)O and 0.2% KH(2)PO(4), pH-4.5, 30 °C, 200 r/min for 96  h with 4% inoculum level. Addition of 1% methanol in response surface methodology optimized-medium led to the production of 67.12 g/L. Scaling up in 10 L fermentor resulted in productivity of 0.80 g/Lh with yield of 0.68 g/g. Efficient synthesis of xylitol esters was achieved with butyric acid (50.32%) and caproic acid (38.36%) in 4 h using Pseudomonas aeruginosa lipase in t-butanol: tetrahydrofuran (1:1 v/v).

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

    PubMed

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

    2007-07-01

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

  10. Laboratory evolution of copper tolerant yeast strains

    PubMed Central

    2012-01-01

    Background Yeast strains endowed with robustness towards copper and/or enriched in intracellular Cu might find application in biotechnology processes, among others in the production of functional foods. Moreover, they can contribute to the study of human diseases related to impairments of copper metabolism. In this study, we investigated the molecular and physiological factors that confer copper tolerance to strains of baker's yeasts. Results We characterized the effects elicited in natural strains of Candida humilis and Saccharomyces cerevisiae by the exposure to copper in the culture broth. We observed that, whereas the growth of Saccharomyces cells was inhibited already at low Cu concentration, C. humilis was naturally robust and tolerated up to 1 g · L-1 CuSO4 in the medium. This resistant strain accumulated over 7 mg of Cu per gram of biomass and escaped severe oxidative stress thanks to high constitutive levels of superoxide dismutase and catalase. Both yeasts were then "evolved" to obtain hyper-resistant cells able to proliferate in high copper medium. While in S. cerevisiae the evolution of robustness towards Cu was paralleled by the increase of antioxidative enzymes, these same activities decreased in evolved hyper-resistant Candida cells. We also characterized in some detail changes in the profile of copper binding proteins, that appeared to be modified by evolution but, again, in a different way in the two yeasts. Conclusions Following evolution, both Candida and Saccharomyces cells were able to proliferate up to 2.5 g · L-1 CuSO4 and to accumulate high amounts of intracellular copper. The comparison of yeasts differing in their robustness, allowed highlighting physiological and molecular determinants of natural and acquired copper tolerance. We observed that different mechanisms contribute to confer metal tolerance: the control of copper uptake, changes in the levels of enzymes involved in oxidative stress response and changes in the copper

  11. The Methanol Economy Project

    SciTech Connect

    Olah, George; Prakash, G. K.

    2014-02-01

    The Methanol Economy Project is based on the concept of replacing fossil fuels with methanol generated either from renewable resources or abundant natural (shale) gas. The full methanol cycle was investigated in this project, from production of methanol through bromination of methane, bireforming of methane to syngas, CO2 capture using supported amines, co-electrolysis of CO2 and water to formate and syngas, decomposition of formate to CO2 and H2, and use of formic acid in a direct formic acid fuel cell. Each of these projects achieved milestones and provided new insights into their respective fields.

  12. Vinegar as an antimicrobial agent for control of Candida spp. in complete denture wearers.

    PubMed

    Pinto, Telma Maria Silva; Neves, Ana Christina Claro; Leão, Mariella Vieira Pereira; Jorge, Antonio Olavo Cardoso

    2008-01-01

    The use of denture is known to increase the carriage of Candida in healthy patients, and the proliferation of Candida albicans strains can be associated with denture-induced stomatitis. The aim of this study was to evaluate the use of vinegar as an antimicrobial agent for control of Candida spp. in complete upper denture wearers. Fifty-five patients were submitted to a detailed clinical interview and oral clinical examination, and were instructed to keep their dentures immersed in a 10% vinegar solution (pH less than 3) overnight for 45 days. Before and after the experimental period, saliva samples were collected for detection of Candida, counting of cfu/mL and identification of species by phenotypical tests (germ tube formation, chlamidoconidia production, and carbohydrate fermentation and assimilation). The results were analyzed using Spearman's correlation and Student's t-test (pCandida yeasts were present in 87.3% of saliva samples before the treatment. A significant reduction was verified in CFU/mL counts of Candida after treatment. A positive correlation between Candida and denture stomatitis was verified, since the decrease of cfu/mL counts was correlated with a reduction in cases of denture stomatitis. Although it was not able to eliminate C. albicans, the immersion of the complete denture in 10% vinegar solution, during the night, reduced the amounts (cfu/mL) of Candida spp. in the saliva and the presence of denture stomatitis in the studied patients. PMID:19082396

  13. Assessment of Antifungal Activity of Bakuchiol on Oral-Associated Candida spp.

    PubMed Central

    Nordin, Mohd-Al-Faisal; Abdul Razak, Fathilah; Himratul-Aznita, Wan Harun

    2015-01-01

    Bakuchiol is an active component of Psoralea glandulosa and Psoralea corylifolia, used in traditional Chinese medicine. The study aimed at investigating the antifungal activity of bakuchiol on planktonic and biofilm forms of orally associated Candida species. The antifungal susceptibility testing was determined by the broth micro dilution technique. Growth kinetics and cell surface hydrophobicity (CSH) of Candida were measured to assess the inhibitory effect of bakuchiol on Candida planktonic cells. Biofilm biomass and cellular metabolic activity were quantitatively estimated by the crystal violet (CV) and the 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-5-[(phenylamino)carbonyl]-2H-tetrazolium hydroxide (XTT) assays. All Candida strains have been shown to be susceptible to bakuchiol with the MIC ranges from 12.5 to 100 μg/mL. Significant decrease in specific growth rates and viable counts demonstrates the inhibitory effect of bakuchiol on Candida planktonic cells. A brief exposure to bakuchiol also reduced CSH of Candida (P < 0.05), indicating altered surface properties of yeast cells towards hydrophobic interfaces. Biofilm biomass and cell metabolic activity were mostly decreased, except for C. glabrata (P = 0.29). The antifungal properties of bakuchiol on Candida species in this in vitro study may give insights into the application in therapeutic strategy against Candida infections. PMID:26633986

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

    PubMed Central

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

    2001-01-01

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

  15. [Rapid identification and susceptibility to killer toxins of yeasts isolated from non-systemic mycoses].

    PubMed

    Sangorrín, M P; Lopes, C A; Rivero, A; Caballero, A C

    2007-01-01

    Rapid identification and susceptibility to killer toxins of yeasts isolated from non-systemic mycoses. The use of quick and reliable yeast identification methods, as well as the development of new antifungal agents with more specific targets, will enable a more efficient treatment of mycoses. In the present work, a total of 53 clinical isolates obtained from non-systemic infections in Neuquén Hospitals and an ophthalmologic clinic in Buenos Aires during 2005, were identified by means of a rapid molecular method (ITS1-5.8S ADNr-ITS2 PCR-RFLP). Additionally, the killer susceptibility of the isolates was tested against reference and indigenous killer yeasts on plate tests. Eight yeast species were identified among the clinical isolates: Candida albicans (52%), Candida parapsilosis (17%), Candida tropicalis (10%), Candida krusei (5%), Candida glabrata (4%), Candida guilliermondii (4%), Kluyveromyces lactis (4%) and Saccharomyces cerevisiae (4%). Sixty-nine percent of the isolates corresponding to the predominant species (C. albicans) were related to vaginal infections. On the other hand, 61% of the yeasts associated with ocular infections were identified as C. parapsilosis. Two indigenous killer isolates DVMais5 and HCMeiss5, belonging to Pichia anomala and P. kluyveri respectively, exhibited the broadest killer spectrum against clinical isolates.

  16. Diversity of culturable yeasts in phylloplane of sugarcane in Thailand and their capability to produce indole-3-acetic acid.

    PubMed

    Limtong, Savitree; Kaewwichian, Rungluk; Yongmanitchai, Wichien; Kawasaki, Hiroko

    2014-06-01

    Yeasts were isolated by the enrichment technique from the phylloplane of 94 samples of sugarcane leaf collected from seven provinces in Thailand. All sugarcane leaf samples contained yeasts and 158 yeast strains were obtained. On the basis of the D1/D2 domain of the large subunit rRNA gene sequence analysis, 144 strains were identified to 24 known species in 14 genera belonging to the Ascomycota viz. Candida akabanensis, Candida dendronema, Candida mesorugosa, Candida michaelii, Candida nivariensis, Candida rugosa, Candida orthopsilosis, Candida quercitrusa, Candida tropicalis, Candida xylopsoci, Cyberlindnera fabianii, Cyberlindnera rhodanensis, Debaryomyces nepalensis, Hannaella aff. coprosmaensis, Hanseniaspora guilliermondii, Kluyveromyces marxianus, Lachancea thermotolerans, Lodderomyces elongisporus, Metschnikowia koreensis, Meyerozyma caribbica, Millerozyma koratensis, Pichia kudriavzevii, Torulaspora delbrueckii and Wickerhamomyces edaphicus, and 12 species in six genera of the Basidiomycota viz . Cryptococcus flavescens, Cryptococcus laurentii, Cryptococcus rajasthanensis, Kwoniella heveanensis, Rhodosporidium fluviale, Rhodosporidium paludigenum, Rhodotorula mucilaginosa, Rhodotorula sesimbrana, Rhodotorula taiwanensis, Sporidiobolus ruineniae, Sporobolomyces carnicolor and Sporobolomyces nylandii. Seven strains were identical or similar to four undescribed species. Another seven strains represented four novels species in the genus Metschnikowia, Nakazawaea, Wickerhamomyces and Yamadazyma. The results revealed 69 % of the isolated strains were ascomycete yeasts and 31 % were basidiomycete yeast. The most prevalent species was M. caribbica with a 23 % frequency of occurrence followed by Rh. taiwanensis (11 %) and C. tropicalis (10 %). All strains were assessed for indole-3-acetic acid (IAA) producing capability showing that 69 strains had the capability of producing IAA when cultivated in yeast extract peptone dextrose broth supplemented with 1

  17. Diversity of culturable yeasts in phylloplane of sugarcane in Thailand and their capability to produce indole-3-acetic acid.

    PubMed

    Limtong, Savitree; Kaewwichian, Rungluk; Yongmanitchai, Wichien; Kawasaki, Hiroko

    2014-06-01

    Yeasts were isolated by the enrichment technique from the phylloplane of 94 samples of sugarcane leaf collected from seven provinces in Thailand. All sugarcane leaf samples contained yeasts and 158 yeast strains were obtained. On the basis of the D1/D2 domain of the large subunit rRNA gene sequence analysis, 144 strains were identified to 24 known species in 14 genera belonging to the Ascomycota viz. Candida akabanensis, Candida dendronema, Candida mesorugosa, Candida michaelii, Candida nivariensis, Candida rugosa, Candida orthopsilosis, Candida quercitrusa, Candida tropicalis, Candida xylopsoci, Cyberlindnera fabianii, Cyberlindnera rhodanensis, Debaryomyces nepalensis, Hannaella aff. coprosmaensis, Hanseniaspora guilliermondii, Kluyveromyces marxianus, Lachancea thermotolerans, Lodderomyces elongisporus, Metschnikowia koreensis, Meyerozyma caribbica, Millerozyma koratensis, Pichia kudriavzevii, Torulaspora delbrueckii and Wickerhamomyces edaphicus, and 12 species in six genera of the Basidiomycota viz . Cryptococcus flavescens, Cryptococcus laurentii, Cryptococcus rajasthanensis, Kwoniella heveanensis, Rhodosporidium fluviale, Rhodosporidium paludigenum, Rhodotorula mucilaginosa, Rhodotorula sesimbrana, Rhodotorula taiwanensis, Sporidiobolus ruineniae, Sporobolomyces carnicolor and Sporobolomyces nylandii. Seven strains were identical or similar to four undescribed species. Another seven strains represented four novels species in the genus Metschnikowia, Nakazawaea, Wickerhamomyces and Yamadazyma. The results revealed 69 % of the isolated strains were ascomycete yeasts and 31 % were basidiomycete yeast. The most prevalent species was M. caribbica with a 23 % frequency of occurrence followed by Rh. taiwanensis (11 %) and C. tropicalis (10 %). All strains were assessed for indole-3-acetic acid (IAA) producing capability showing that 69 strains had the capability of producing IAA when cultivated in yeast extract peptone dextrose broth supplemented with 1

  18. Oral Candida spp carriers: its prevalence in patients with type 2 Diabetes Mellitus*

    PubMed Central

    Martinez, Ramon Felipe Fernandez; Jaimes-Aveldañez, Alejandra; Hernández-Pérez, Francisco; Arenas, Roberto; Miguel, Guadalupe Fabián-San

    2013-01-01

    BACKGROUND: Prevalence of oral candidiasis in diabetic patients is 13.7-64%. Candida albicans was the most frequently isolated species (75-86.5%). OBJECTIVE: To obtain the prevalence of Candida carriers among patients with type 2 diabetes mellitus to identify the species of the yeast. Study design: It is an open, observational, descriptive, cross-sectional, and prospective study. METHODS: We included voluntary patients from the National Diabetes Marathon and performed a blood glucose measurement, sialometry test, Gram-stained exfoliative cytology, and culture on Sabouraud dextrose agar and CHROMagar Candida TM. Results were analyzed using descriptive statistics. RESULTS: We examined 141 patients (mean age 57 years): 103 women (73%) and 38 men (26.9%). Exfoliative cytology was positive in 32 cases (23 with oral lesions); 78 had oral lesions but no Candida (93.9%). Candida was isolated in 58 patients (41.1%), 21 (45.6 %) had blood glucose greater than 126 mg/dl, and 37 (38.9%) had less than 126 mg/dl. The most frequent species was C. albicans (82.7%). Forty-two Candida carriers had salivary flow greater than 20 mm (72.4%), and 16 (27.5%) had hyposalivation. Candida was isolated in 25 of 79 patients with dental prosthesis (31.6%), 9 of 15 were smokers (60%), and 22 of 71 had symptoms (30.9%). CONCLUSIONS: Prevalence of oral Candida carriers in patients with type 2 diabetes mellitus in Mexico was similar to that found in other countries; exfoliative cytology was effective in finding Candida; salivary flow rate, use of prosthesis, and presence of oral lesions and symptoms were similar in oral Candida carriers and negative patients. Most smokers were Candida carriers. PMID:23739717

  19. Species-specific identification of Candida krusei by hybridization with the CkF1,2 DNA probe.

    PubMed Central

    Carlotti, A; Couble, A; Domingo, J; Miroy, K; Villard, J

    1996-01-01

    The species specificity of the Candida krusei DNA fingerprinting probe CkF1,2 has been investigated. A total of 149 pathogenic and nonpathogenic fungal and bacterial DNAs were screened with CkF1,2. The probe was cold labeled with peroxidase, and its specificity was assessed by using Southern blot, dot blot, and colony blot hybridization. Its sensitivity was determined by dot blot hybridization. The CkF1,2 probe proved to be species specific. It hybridized with DNA for the 112 C. krusei strains studied, whereas it failed to hybridize under low-stringency conditions to 37 DNAs from 27 different yeast species, including Candida albicans, Candida glabrata, Candida norvegensis, Candida inconspicua, Candida tropicalis, Candida valida, Candida zeylanoides, and Yarrowia lipolytica, as well as DNAs from the filamentous fungi and bacteria tested. However, CkF1,2 hybridized strongly with DNA of the yeast species Issatchenkia orientalis, the putative ascogenous perfect state of C. krusei. Amounts as small as 60 to 120 ng of C. krusei target DNA were detected by dot blot hybridization with CkF1,2. It permitted the direct screening of colony blots for early identification. The CkF1,2 probe has potential value as a diagnostic reagent for identifying C. krusei. PMID:8784578

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

    PubMed Central

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

    2014-01-01

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

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

    PubMed

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

    2014-01-01

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

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

    PubMed

    Kurtzman, Cletus P

    2016-07-01

    DNA sequence analyses have demonstrated that species of the polyphyletic anamorphic ascomycete genus Candida may be members of described teleomorphic genera, members of the Candida tropicalis clade upon which the genus Candida is circumscribed, or members of isolated clades that represent undescribed genera. From phylogenetic analysis of gene sequences from nuclear large subunit rRNA, mitochondrial small subunit rRNA and cytochrome oxidase II, Candida auringiensis (NRRL Y-17674(T), CBS 6913(T)), Candida salmanticensis (NRRL Y-17090(T), CBS 5121(T)), and Candida tartarivorans (NRRL Y-27291(T), CBS 7955(T)) were shown to be members of an isolated clade and are proposed for reclassification in the genus Groenewaldozyma gen. nov. (MycoBank MB 815817). Neighbouring taxa include species of the Wickerhamiella clade and Candida blankii. PMID:27142089

  3. Adhesion of Candida albicans to HeLa cells: studies using polystyrene beads.

    PubMed

    Miyauchi, Masayoshi; Giummelly, Philippe; Yazawa, Shin; Okawa, Yoshio

    2007-03-01

    The adherence to HeLa cells by the yeast-type cells of the Candida albicans NIH A-207 strain cultivated for 2 d at 27 degrees C in the yeast extract-added Sabouraud liquid medium (YSLM) and the 500 mM galactose-added yeast nitrogen base medium (YNB-Gal) was compared. The yeast cells cultured in the YNB-Gal clearly increased the adherence to the HeLa cells compared to the YSLM. The adherence drastically decreased by pronase treatment of the yeast cells. Next, to define the sugar receptors of the yeast cells, lactosylceramide (LC)-, the H type 1 antigen (HA)-, Lewis(a) antigen (Le(a))-, mannan- and BSA-coated polystyrene beads were used for the adherence to the yeast cells. Only the LC- and HA-beads were bound to the yeast cells. The adherence of the two beads to the yeast cells cultured in the YNB-Gal was higher than that to the yeast cells cultured in the YSLM. The yeast cell wall mannan-coated polystyrene beads did not adhere at all to the Hela cells. Based on these results, it is evident that the protein parts involving the LC and HA receptors on the surface of the yeast cells correlate with the adherence to the HeLa cells. PMID:17329863

  4. Yeast cell differentiation: Lessons from pathogenic and non-pathogenic yeasts.

    PubMed

    Palková, Zdena; Váchová, Libuše

    2016-09-01

    Yeasts, historically considered to be single-cell organisms, are able to activate different differentiation processes. Individual yeast cells can change their life-styles by processes of phenotypic switching such as the switch from yeast-shaped cells to filamentous cells (pseudohyphae or true hyphae) and the transition among opaque, white and gray cell-types. Yeasts can also create organized multicellular structures such as colonies and biofilms, and the latter are often observed as contaminants on surfaces in industry and medical care and are formed during infections of the human body. Multicellular structures are formed mostly of stationary-phase or slow-growing cells that diversify into specific cell subpopulations that have unique metabolic properties and can fulfill specific tasks. In addition to the development of multiple protective mechanisms, processes of metabolic reprogramming that reflect a changed environment help differentiated individual cells and/or community cell constituents to survive harmful environmental attacks and/or to escape the host immune system. This review aims to provide an overview of differentiation processes so far identified in individual yeast cells as well as in multicellular communities of yeast pathogens of the Candida and Cryptococcus spp. and the Candida albicans close relative, Saccharomyces cerevisiae. Molecular mechanisms and extracellular signals potentially involved in differentiation processes are also briefly mentioned. PMID:27084693

  5. Yeast cell differentiation: Lessons from pathogenic and non-pathogenic yeasts.

    PubMed

    Palková, Zdena; Váchová, Libuše

    2016-09-01

    Yeasts, historically considered to be single-cell organisms, are able to activate different differentiation processes. Individual yeast cells can change their life-styles by processes of phenotypic switching such as the switch from yeast-shaped cells to filamentous cells (pseudohyphae or true hyphae) and the transition among opaque, white and gray cell-types. Yeasts can also create organized multicellular structures such as colonies and biofilms, and the latter are often observed as contaminants on surfaces in industry and medical care and are formed during infections of the human body. Multicellular structures are formed mostly of stationary-phase or slow-growing cells that diversify into specific cell subpopulations that have unique metabolic properties and can fulfill specific tasks. In addition to the development of multiple protective mechanisms, processes of metabolic reprogramming that reflect a changed environment help differentiated individual cells and/or community cell constituents to survive harmful environmental attacks and/or to escape the host immune system. This review aims to provide an overview of differentiation processes so far identified in individual yeast cells as well as in multicellular communities of yeast pathogens of the Candida and Cryptococcus spp. and the Candida albicans close relative, Saccharomyces cerevisiae. Molecular mechanisms and extracellular signals potentially involved in differentiation processes are also briefly mentioned.

  6. Yeast succession in the Amazon fruit Parahancornia amapa as resource partitioning among Drosophila spp.

    PubMed Central

    Morais, P B; Martins, M B; Klaczko, L B; Mendonça-Hagler, L C; Hagler, A N

    1995-01-01

    The succession of yeasts colonizing the fallen ripe amapa fruit, from Parahancornia amapa, was examined. The occupation of the substrate depended on both the competitive interactions of yeast species, such as the production of killer toxins, and the selective dispersion by the drosophilid guild of the amapa fruit. The yeast community associated with this Amazon fruit differed from those isolated from other fruits in the same forest. The physiological profile of these yeasts was mostly restricted to the assimilation of a few simple carbon sources, mainly L-sorbose, D-glycerol, DL-lactate, cellobiose, and salicin. Common fruit-associated yeasts of the genera Kloeckera and Hanseniaspora, Candida guilliermondii, and Candida krusei colonized fruits during the first three days after the fruit fell. These yeasts were dispersed and served as food for the invader Drosophila malerkotliana. The resident flies of the Drosophila willistoni group fed selectively on patches of yeasts colonizing fruits 3 to 10 days after the fruit fell. The killer toxin-producing yeasts Pichia kluyveri var. kluyveri and Candida fructus were probably involved in the exclusion of some species during the intermediate stages of fruit deterioration. An increase in pH, inhibiting toxin activity and the depletion of simple sugars, may have promoted an increase in yeast diversity in the later stages of decomposition. The yeast succession provided a patchy environment for the drosophilids sharing this ephemeral substrate. PMID:8534092

  7. Yeast Infection and Diabetes Mellitus among Pregnant Mother in Malaysia

    PubMed Central

    Sopian, Iylia Liyana; Shahabudin, Sa’adiah; Ahmed, Mowaffaq Adam; Lung, Leslie Than Thian; Sandai, Doblin

    2016-01-01

    Background Vaginal yeast infection refers to irritation of the vagina due to the presence of opportunistic yeast of the genus Candida (mostly Candida albicans). About 75% of women will have at least one episode of vaginal yeast infection during their lifetime. Several studies have shown that pregnancy and uncontrolled diabetes increase the infection risk. Reproductive hormone fluctuations during pregnancy and elevated glucose levels characteristic of diabetes provide the carbon needed for Candida overgrowth and infection. The goal of this study was to determine the prevalence of vaginal yeast infection among pregnant women with and without diabetes. Methods This was a case-control study using cases reports from Kepala Batas Health Clinic, Penang State, Malaysia from 2006 to 2012. In total, 740 pregnant ladies were chosen as sample of which 370 were diabetic and 370 were non-diabetic cases. Results No relationship between diabetes and the occurrence of vaginal yeast infection in pregnant women was detected, and there was no significant association between infection and age group, race or education level. Conclusion In conclusion, within radius of this study, vaginal yeast infection can occur randomly in pregnant women. PMID:27540323

  8. Yeast and yeast-like diversity in the southernmost glacier of Europe (Calderone Glacier, Apennines, Italy).

    PubMed

    Branda, Eva; Turchetti, Benedetta; Diolaiuti, Guglielmina; Pecci, Massimo; Smiraglia, Claudio; Buzzini, Pietro

    2010-06-01

    The present study reports the characterization of psychrophilic yeast and yeast-like diversity in cold habitats (superficial and deep sediments, ice cores and meltwaters) of the Calderone Glacier (Italy), which is the southernmost glacier in Europe. After incubation at 4 and 20 degrees C, sediments contained about 10(2)-10(3) CFU of yeasts g(-1). The number of viable yeast cells in ice and meltwaters was several orders of magnitude lower. The concomitant presence of viable bacteria and filamentous fungi has also been observed. In all, 257 yeast strains were isolated and identified by 26S rRNA gene D1/D2 and internal transcribed spacers (1 and 2) sequencing as belonging to 28 ascomycetous and basidiomycetous species of 11 genera (Candida, Cystofilobasidium, Cryptococcus, Dioszegia, Erythrobasidium, Guehomyces, Mastigobasidium, Mrakia, Mrakiella, Rhodotorula and Sporobolomyces). Among them, the species Cryptococcus gastricus accounted for almost 40% of the total isolates. In addition, 12 strains were identified as belonging to the yeast-like species Aureobasidium pullulans and Exophiala dermatitidis, whereas 15 strains, presumably belonging to new species, yet to be described, were also isolated. Results herein reported indicate that the Calderone Glacier, although currently considered a vanishing ice body due to the ongoing global-warming phenomenon, still harbors viable psychrophilic yeast populations. Differences of yeast and yeast-like diversity between the glacier under study and other worldwide cold habitats are also discussed.

  9. Study on the comparative activity of echinocandins on murine gut colonization by Candida albicans.

    PubMed

    Maraki, Sofia; Hamilos, George; Dimopoulou, Dimitra; Andrianaki, Angeliki M; Karageorgiadis, Alexander Steven; Kyvernitakis, Andreas; Lionakis, Stelios; Kofteridis, Diamantis P; Samonis, George

    2015-08-01

    Colonization of the gastrointestinal (GI) tract by Candida species is a principal pathogenetic event for development of invasive candidiasis. Importantly, the effect of echinocandins, the preferred antifungal agents for treatment of invasive candidiasis, on GI tract colonization by Candida spp. is currently unknown. Herein, we used an established model of persistent murine GI tract colonization by Candida albicans to test the ability of different echinocandins to eradicate the yeast from murine gut. Adult male Crl:CD1 (ICR) BR mice were fed with chow containing C. albicans and subsequently treated with different echinocandins or normal saline via daily intraperitoneal injections for 10 days. Quantitative stool cultures were performed immediately before (week one), and weekly for three months after discontinuation of treatment. Notably, treatment with all three echinocandins used (caspofungin, anidulafungin, and micafungin) resulted in eradication of Candida albicans from the stools, as evidenced by the significant reduction of yeast cells from a mean of 4.2 log10 CFU/g of stool before treatment (week one of colonization) to undetectable (<2 log10 CFU/g of stool) levels (week 12, P < 0.0001). In contrast, there was no significant reduction of Candida yeast cells in the stools of control mice. Collectively, the ability of echinocandins to eradicate C. albicans from the stools could have important implications in prophylaxis of high-risk patients for development of invasive candidiasis originating from the GI tract.

  10. In situ rheology of yeast biofilms.

    PubMed

    Brugnoni, Lorena I; Tarifa, María C; Lozano, Jorge E; Genovese, Diego

    2014-01-01

    The aim of the present work was to investigate the in situ rheological behavior of yeast biofilms growing on stainless steel under static and turbulent flow. The species used (Rhodototula mucilaginosa, Candida krusei, Candida kefyr and Candida tropicalis) were isolated from a clarified apple juice industry. The flow conditions impacted biofilm composition over time, with a predominance of C. krusei under static and turbulent flow. Likewise, structural variations occurred, with a tighter appearance under dynamic flow. Under turbulent flow there was an increase of 112 μm in biofilm thickness at 11 weeks (p < 0.001) and cell morphology was governed by hyphal structures and rounded cells. Using the in situ growth method introduced here, yeast biofilms were determined to be viscoelastic materials with a predominantly solid-like behavior, and neither this nor the G'0 values were significantly affected by the flow conditions or the growth time, and at large deformations their weak structure collapsed beyond a critical strain of about 1.5-5%. The present work could represent a starting point for developing in situ measurements of yeast rheology and contribute to a thin body of knowledge about fungal biofilm formation. PMID:25428768

  11. Methanol partial oxidation reformer

    DOEpatents

    Ahmed, S.; Kumar, R.; Krumpelt, M.

    1999-08-17

    A partial oxidation reformer is described comprising a longitudinally extending chamber having a methanol, water and an air inlet and an outlet. An igniter mechanism is near the inlets for igniting a mixture of methanol and air, while a partial oxidation catalyst in the chamber is spaced from the inlets and converts methanol and oxygen to carbon dioxide and hydrogen. Controlling the oxygen to methanol mole ratio provides continuous slightly exothermic partial oxidation reactions of methanol and air producing hydrogen gas. The liquid is preferably injected in droplets having diameters less than 100 micrometers. The reformer is useful in a propulsion system for a vehicle which supplies a hydrogen-containing gas to the negative electrode of a fuel cell. 7 figs.

  12. Methanol partial oxidation reformer

    DOEpatents

    Ahmed, Shabbir; Kumar, Romesh; Krumpelt, Michael

    1999-01-01

    A partial oxidation reformer comprising a longitudinally extending chamber having a methanol, water and an air inlet and an outlet. An igniter mechanism is near the inlets for igniting a mixture of methanol and air, while a partial oxidation catalyst in the chamber is spaced from the inlets and converts methanol and oxygen to carbon dioxide and hydrogen. Controlling the oxygen to methanol mole ratio provides continuous slightly exothermic partial oxidation reactions of methanol and air producing hydrogen gas. The liquid is preferably injected in droplets having diameters less than 100 micrometers. The reformer is useful in a propulsion system for a vehicle which supplies a hydrogen-containing gas to the negative electrode of a fuel cell.

  13. Methanol partial oxidation reformer

    DOEpatents

    Ahmed, Shabbir; Kumar, Romesh; Krumpelt, Michael

    2001-01-01

    A partial oxidation reformer comprising a longitudinally extending chamber having a methanol, water and an air inlet and an outlet. An igniter mechanism is near the inlets for igniting a mixture of methanol and air, while a partial oxidation catalyst in the chamber is spaced from the inlets and converts methanol and oxygen to carbon dioxide and hydrogen. Controlling the oxygen to methanol mole ratio provides continuous slightly exothermic partial oxidation reactions of methanol and air producing hydrogen gas. The liquid is preferably injected in droplets having diameters less than 100 micrometers. The reformer is useful in a propulsion system for a vehicle which supplies a hydrogen-containing gas to the negative electrode of a fuel cell.

  14. Methanol partial oxidation reformer

    DOEpatents

    Ahmed, S.; Kumar, R.; Krumpelt, M.

    1999-08-24

    A partial oxidation reformer is described comprising a longitudinally extending chamber having a methanol, water and an air inlet and an outlet. An igniter mechanism is near the inlets for igniting a mixture of methanol and air, while a partial oxidation catalyst in the chamber is spaced from the inlets and converts methanol and oxygen to carbon dioxide and hydrogen. Controlling the oxygen to methanol mole ratio provides continuous slightly exothermic partial oxidation reactions of methanol and air producing hydrogen gas. The liquid is preferably injected in droplets having diameters less than 100 micrometers. The reformer is useful in a propulsion system for a vehicle which supplies a hydrogen-containing gas to the negative electrode of a fuel cell. 7 figs.

  15. [Acute Pyelonephritis and Candidemia Due to Candida lusitaniae: A Case Report].

    PubMed

    Tsuboi, Motoyuki; Uno, Shunsuke; Hase, Ryota; Yano, Yudai; Sando, Eiichiro; Otsuka, Yoshihito; Hosokawa, Naoto

    2016-03-01

    Although candiduria is becoming increasingly common among hospitalized patients, Candida lusitaniae is a rare pathogen that account for less than 1% of Candida species isolated from urine. Ascending pyelonephritis and candidemia due to Candida species are uncommon complications. We report herein on a case of acute pyelonephritis and candidemia due to C. lusitaniae. A 66-year-old man presented with a high fever during hospitalization at our hospital following septic shock due to ischial osteomyelitis treated with tazobactam/piperacillin for 29 days. We suspected acute pyelonephritis, and urinary Gram staining showed only yeasts and leucocytes. The next day, blood culture and urine culture tested positive and showed yeast-like fungi. We diagnosed acute pyelonephritis and candidemia due to Candida species and started treatment with fluconazole. C. lusitaniae was identified on the hospital day 34 and treated with fluconazole for 14 days. Candida albicans was the most prevalent species isolated from the urinary tract, however non-albicans Candida species have emerged and are now dominant because of the advent and increasing use of fluconazole. C. lusitaniae is a rare but important pathogen, that is generally susceptible to fluconazole and resistant to amphotericin B. It is necessary to choose an appropriately effective antifungal drug based on identification of the fungal species. PMID:27197441

  16. [Acute Pyelonephritis and Candidemia Due to Candida lusitaniae: A Case Report].

    PubMed

    Tsuboi, Motoyuki; Uno, Shunsuke; Hase, Ryota; Yano, Yudai; Sando, Eiichiro; Otsuka, Yoshihito; Hosokawa, Naoto

    2016-03-01

    Although candiduria is becoming increasingly common among hospitalized patients, Candida lusitaniae is a rare pathogen that account for less than 1% of Candida species isolated from urine. Ascending pyelonephritis and candidemia due to Candida species are uncommon complications. We report herein on a case of acute pyelonephritis and candidemia due to C. lusitaniae. A 66-year-old man presented with a high fever during hospitalization at our hospital following septic shock due to ischial osteomyelitis treated with tazobactam/piperacillin for 29 days. We suspected acute pyelonephritis, and urinary Gram staining showed only yeasts and leucocytes. The next day, blood culture and urine culture tested positive and showed yeast-like fungi. We diagnosed acute pyelonephritis and candidemia due to Candida species and started treatment with fluconazole. C. lusitaniae was identified on the hospital day 34 and treated with fluconazole for 14 days. Candida albicans was the most prevalent species isolated from the urinary tract, however non-albicans Candida species have emerged and are now dominant because of the advent and increasing use of fluconazole. C. lusitaniae is a rare but important pathogen, that is generally susceptible to fluconazole and resistant to amphotericin B. It is necessary to choose an appropriately effective antifungal drug based on identification of the fungal species.

  17. The influence of Aster x salignus Willd. Invasion on the diversity of soil yeast communities

    NASA Astrophysics Data System (ADS)

    Glushakova, A. M.; Kachalkin, A. V.; Chernov, I. Yu.

    2016-07-01

    The annual dynamics of yeast communities were studied in the soddy-podzolic soil under the thickets of Aster x salignus Willd., one of the widespread invasive plant species in central Russia. Yeast groups in the soils under continuous aster thickets were found to differ greatly from the yeast communities in the soils under the adjacent indigenous meadow vegetation. In both biotopes the same species ( Candida vartiovaarae, Candida sake, and Cryptococcus terreus) are dominants. However, in the soils under indigenous grasses, eurybiontic yeasts Rhodotorula mucilaginosa, which almost never occur in the soil under aster, are widespread. In the soil under aster, the shares of other typical epiphytic and pedobiontic yeast fungi (ascomycetic species Wickerhamomyces aniomalus, Barnettozyma californica and basidiomycetic species Cystofilobasidium macerans, Guehomyces pullulans) significantly increase. Thus, the invasion of Aster x salignus has a clear effect on soil yeast complexes reducing their taxonomic and ecological diversity.

  18. Detection and identification of wild yeast contaminants of the industrial fuel ethanol fermentation process.

    PubMed

    Basílio, A C M; de Araújo, P R L; de Morais, J O F; da Silva Filho, E A; de Morais, M A; Simões, D A

    2008-04-01

    Monitoring for wild yeast contaminants is an essential component of the management of the industrial fuel ethanol manufacturing process. Here we describe the isolation and molecular identification of 24 yeast species present in bioethanol distilleries in northeast Brazil that use sugar cane juice or cane molasses as feeding substrate. Most of the yeast species could be identified readily from their unique amplification-specific polymerase chain reaction (PCR) fingerprint. Yeast of the species Dekkera bruxellensis, Candida tropicalis, Pichia galeiformis, as well as a species of Candida that belongs to the C. intermedia clade, were found to be involved in acute contamination episodes; the remaining 20 species were classified as adventitious. Additional physiologic data confirmed that the presence of these major contaminants cause decreased bioethanol yield. We conclude that PCR fingerprinting can be used in an industrial setting to monitor yeast population dynamics to early identify the presence of the most important contaminant yeasts.

  19. Candida albicans mutant construction and characterization of selected virulence determinants.

    PubMed

    Motaung, T E; Albertyn, J; Pohl, C H; Köhler, Gerwald

    2015-08-01

    Candida albicans is a diploid, polymorphic yeast, associated with humans, where it mostly causes no harm. However, under certain conditions it can cause infections ranging from superficial to life threatening. This ability to become pathogenic is often linked to the immune status of the host as well as the expression of certain virulence factors by the yeast. Due to the importance of C. albicans as a pathogen, determination of the molecular mechanisms that allow this yeast to cause disease is important. These studies rely on the ability of researchers to create deletion mutants of specific genes in order to study their function. This article provides a critical review of the important techniques used to create deletion mutants in C. albicans and highlights how these deletion mutants can be used to determine the role of genes in the expression of virulence factors in vitro.

  20. Pichia anomala (Candida pelliculosa) Fungemia in a Patient with Sickle Cell Disease

    PubMed Central

    Chan, Austin W.; Cartwright, Emily J.; Reddy, Sujan C.; Kraft, Colleen S.; Wang, Yun F.

    2015-01-01

    This case report discusses a patient with sickle cell disease who presented with fungemia from Pichia anomala (teleomorph: Candida pelliculosa). The organism was identified as P. anomala by MALDI-TOF VITEK mass spectrometry and VITEK 2 yeast identification card. Pichia anomala should be considered in sickle cell patients with recurrent fungemia. PMID:23884540

  1. Lodderomyces elongisporus masquerading as Candida parapsilosis as a cause of bloodstream infections.

    PubMed

    Lockhart, Shawn R; Messer, Shawn A; Pfaller, Michael A; Diekema, Daniel J

    2008-01-01

    Ten yeast bloodstream isolates identified as Candida parapsilosis by conventional methods grew as turquoise blue colonies on Chromagar media. Subsequent sequence analysis showed that these isolates were the species Lodderomyces elongisporus. To our knowledge, this is the first published report of L. elongisporus as a cause of human disease.

  2. Zygoascus hellenicus gen. nov., sp. nov., the teleomorph of Candida hellenica (= C. inositophila = C. steatolytica).

    PubMed

    Smith, M T

    1986-01-01

    The anamorphic yeast species Candida hellenica, C. inositophila and C. steatolytica were found to constitute haploid mating types of an undescribed, filamentous heterothallic Endomycete. The new genus Zygoascus is proposed for the teleomorph. Descriptions are given of the genus and type species, Z. hellenicus.

  3. PRIMARY STRUCTURE OF THE CYTOCHROME P450 LANOSTEROL 14A-DEMETHYLASE GENE FROM CANDIDA TROPICALIS

    EPA Science Inventory

    We report the nucleotide sequence of the gene and flanking DNA for the cytochrome P450 lanosterol 14 alpha-demethylase (14DM) from the yeast Candida tropicalis ATCC750. An open reading frame (ORF) of 528 codons encoding a 60.9-kD protein is identified. This ORF includes a charact...

  4. Comparison of CLSI broth macrodilution and microdilution methods for echinocandin susceptibility testing of 5 Candida species.

    PubMed

    Bopp, Lawrence H; Baltch, Aldona L; Ritz, William J; Smith, Raymond P

    2011-11-01

    In order to compare the Clinical and Laboratory Standards Institute (CLSI) broth macrodilution and microdilution methods of susceptibility testing for echinocandins and yeast, 55 strains of Candida representing 5 species were tested using the CLSI-recommended broth macro- and microdilution methods. Small (1-3 log(2)) but potentially important method-, species-, and drug-dependent differences in MICs were observed.

  5. Cancer drugs inhibit morphogenesis in the human fungal pathogen, Candida albicans.

    PubMed

    Routh, Madhushree M; Chauhan, Nitin M; Karuppayil, S Mohan

    2013-01-01

    Candida infections are very common in cancer patients and it is a common practice to prescribe antifungal antibiotics along with anticancer drugs. Yeast to hyphal form switching is considered to be important in invasive candidiasis. Targeting morphogenetic switching may be useful against invasive candidiasis. In this study, we report the antimorphogenetic properties of thirty cancer drugs. PMID:24516452

  6. The Candida Pathogenic Species Complex

    PubMed Central

    Turner, Siobhán A.; Butler, Geraldine

    2014-01-01

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

  7. Antifungal resistance in yeast vaginitis.

    PubMed Central

    Dun, E.

    1999-01-01

    The increased number of vaginal yeast infections in the past few years has been a disturbing trend, and the scientific community has been searching for its etiology. Several theories have been put forth to explain the apparent increase. First, the recent widespread availability of low-dosage, azole-based over-the-counter antifungal medications for vaginal yeast infections encourages women to self-diagnose and treat, and women may be misdiagnosing themselves. Their vaginitis may be caused by bacteria, parasites or may be a symptom of another underlying health condition. As a result, they may be unnecessarily and chronically expose themselves to antifungal medications and encourage fungal resistance. Second, medical technology has increased the life span of seriously immune compromised individuals, yet these individuals are frequently plagued by opportunistic fungal infections. Long-term and intense azole-based antifungal treatment has been linked to an increase in resistant Candida and non-Candida species. Thus, the future of limiting antifungal resistance lies in identifying the factors promoting resistance and implementing policies to prevent it. PMID:10907778

  8. Yeasts in a hospital for patients with skin diseases

    PubMed Central

    Somerville, Dorothy A.

    1972-01-01

    The incidence and acquisition of Candida albicans and other yeasts in two wards of a skin hospital is described. Carriage rates on the skin in hospital patients is higher than is generally supposed, and cutaneous sites may act as sources of infection with these organisms. PMID:4567312

  9. Alcoholic Fermentation of d-Xylose by Yeasts

    PubMed Central

    Toivola, Ansa; Yarrow, David; van den Bosch, Eduard; van Dijken, Johannes P.; Scheffers, W. Alexander

    1984-01-01

    Type strains of 200 species of yeasts able to ferment glucose and grow on xylose were screened for fermentation of d-xylose. In most of the strains tested, ethanol production was negligible. Nineteen were found to produce between 0.1 and 1.0 g of ethanol per liter. Strains of the following species produce more than 1 g of ethanol per liter in the fermentation test with 2% xylose: Brettanomyces naardenensis, Candida shehatae, Candida tenuis, Pachysolen tannophilus, Pichia segobiensis, and Pichia stipitis. Subsequent screening of these yeasts for their capacity to ferment d-cellobiose revealed that only Candida tenuis CBS 4435 was a good fermenter of both xylose and cellobiose under the test conditions used. PMID:16346558

  10. Germination of Candida albicans induced by proline.

    PubMed Central

    Dabrowa, N; Taxer, S S; Howard, D H

    1976-01-01

    Blastospores of Candida albicans germinated in proline-biotin-buffer medium incubated at 37 C. Certain other amino acids in the glatamate, asparate, and pyruvate families also fostered germinaton but generally to a lesser extent than did proline. L-Cysteine, D-proline, and certain structural analogues of L-proline inhibited proline-stimualted germination. The concentration of phosphate and glucose was crucial to amino acid-stimulated germination of C. albicans. Clinical isolates and stock cultures varied in their response to the germ tube-inducing activity of proline or other amino acids. The proline-buffer medium cannot be used in a diagnostic test for production of germ tubes by isolates of yeasts. PMID:5375

  11. The parasexual lifestyle of Candida albicans.

    PubMed

    Bennett, Richard J

    2015-12-01

    Candida albicans is both a prevalent human commensal and the most commonly encountered human fungal pathogen. This lifestyle is dependent on the ability of the fungus to undergo rapid genetic and epigenetic changes, often in response to specific environmental cues. A parasexual cycle in C. albicans has been defined that includes several unique properties when compared to the related model yeast, Saccharomyces cerevisiae. Novel features include strict regulation of mating via a phenotypic switch, enhanced conjugation within a sexual biofilm, and a program of concerted chromosome loss in place of a conventional meiosis. It is expected that several of these adaptations co-evolved with the ability of C. albicans to colonize the mammalian host.

  12. Comparison of three methods for recovery of yeasts from hands of health-care workers.

    PubMed Central

    Strausbaugh, L J; Sewell, D L; Tjoelker, R C; Heitzman, T; Webster, T; Ward, T T; Pfaller, M A

    1996-01-01

    This study compared three methods for the detection of yeasts on the hands of 30 nurses: (i) direct finger impressions on inhibitory mold agar plates, (ii) bag washes in brain heart infusion broth, and (iii) bag washes in brain heart infusion broth supplemented with gentamicin and vancomycin. The antimicrobial agent-supplemented bag wash method identified the greatest number of yeast carriers and yielded the most yeast isolates, especially non-C. albicans Candida spp. PMID:8789043

  13. Candida parapsilosis prosthetic valve endocarditis

    PubMed Central

    Silva-Pinto, André; Ferraz, Rita; Casanova, Jorge; Sarmento, António; Santos, Lurdes

    2015-01-01

    Candida endocarditis is a rare infection associated with high mortality and morbidity. There are still some controversies about Candida endocarditis treatment, especially about the treatment duration. We report a case of a Candida parapsilosis endocarditis that presented as a lower limb ischemia. The patient was surgically treated with a cryopreserved homograft aortic replacement. We used intravenous fluconazole 800 mg as initial treatment, followed with 12 months of 400 mg fluconazole per os. The patient outcome was good. PMID:26288749

  14. Counting Yeast.

    ERIC Educational Resources Information Center

    Bealer, Jonathan; Welton, Briana

    1998-01-01

    Describes changes to a traditional study of population in yeast colonies. Changes to the procedures include: (1) only one culture per student team; (2) cultures are inoculated only once; and (3) the same tube is sampled daily. (DDR)

  15. Candida's arranged marriage.

    PubMed

    Gow, N A; Brown, A J; Odds, F C

    2000-07-14

    Biologists who study the fungus Candida albicans have always assumed that this organism reproduces asexually because they have not found evidence of mating, meiosis, or a haploid stage of the life cycle. However, as Gow et al. explain in a Perspective, sequencing of the C. albicans genome has revealed the existence of a possible mating type locus. This finding has now been extended to demonstrate actual mating in the fungus (Hull et al., Magee and Magee).

  16. Dietary methanol and autism.

    PubMed

    Walton, Ralph G; Monte, Woodrow C

    2015-10-01

    The authors sought to establish whether maternal dietary methanol during pregnancy was a factor in the etiology of autism spectrum disorders. A seven item questionnaire was given to women who had given birth to at least one child after 1984. The subjects were solicited from a large primary care practice and several internet sites and separated into two groups - mothers who had given birth to a child with autism and those who had not. Average weekly methanol consumption was calculated based on questionnaire responses. 550 questionnaires were completed by women who gave birth to a non-autistic child. On average these women consumed 66.71mg. of methanol weekly. 161 questionnaires were completed by women who had given birth to an autistic child. The average estimated weekly methanol consumption for this group was 142.31mg. Based on the results of the Wilcoxon rank sum-test, we see a significant difference between the reported methanol consumption rates of the two groups. This study suggests that women who have given birth to an autistic child are likely to have had higher intake of dietary sources of methanol than women who have not. Further investigation of a possible link of dietary methanol to autism is clearly warranted.

  17. 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.

  18. Prevalence of Candida species in fresh fruit juices.

    PubMed

    Uhitil, Suncica; Hadina, Suzana; Granić, Kornelija; Jaksić, Slavica

    2009-12-01

    Fruit juices are popular soft drinks with an important role in human nutrition. Fruit juices are often infested by yeast species that can survive different storage conditions. The aim of this study was to determine the degree of yeast contamination of freshly squeezed juices in three large supermarkets in Zagreb, Croatia. The analysis included 84 juice samples obtained from freshly squeezed orange, lemon, grapefruit, and apples. Their acidity varied between pH 2.1 and pH 4.9. Juice samples were plated directly on Sabouraud 4 % glucose Agar (Merck, 1.05438) and processed according to standardised methods (HRN ISO 7954:2002). Yeasts were isolated in all 84 samples and ranged between 0.005 x 103 and 23 x 103 colony forming units per mL (CFU mL-1). The most common yeasts identified using the API 20C AUX yeast kit included Candida guillermondii, C. krusei, C. famata, C. spherica, C. colliculosa, C. albicans, Trichosporon mucoides, Kloeckera spp. and yeast-like fungus Cryptococcus neoformans. C. guillermondii prevailed in 55.95 % of all samples.

  19. Rapid Identification of Candida dubliniensis by Indirect Immunofluorescence Based on Differential Localization of Antigens on C. dubliniensis Blastospores and Candida albicans Germ Tubes

    PubMed Central

    Bikandi, Joseba; Millán, Rosario San; Moragues, María D.; Cebas, Gontzal; Clarke, Mary; Coleman, David C.; Sullivan, Derek J.; Quindós, Guillermo; Pontón, José

    1998-01-01

    There is a clear need for the development of a rapid and reliable test for the identification of Candida dubliniensis and for the discrimination of this species from Candida albicans. In the present study we have investigated the potential use of C. dubliniensis-specific antigens as a basis for its identification. We produced an anti-C. dubliniensis serum which, after adsorption with C. albicans blastospores, was found to differentially label C. dubliniensis isolates in an indirect immunofluorescence test. In this test, the antiserum reacted with blastospores and germ tubes of C. dubliniensis and with blastospores of Candida krusei and Rhodotorula rubra but did not react with blastospores of several other Candida species including C. albicans. The antiserum also reacted with C. albicans germ tubes. The anti-C. dubliniensis adsorbed serum reacted with specific components of 25, 28, 37, 40, 52, and 62 kDa in the C. dubliniensis extract and with a variety of antigens from other yeast species. The antigens from non-C. dubliniensis yeasts showing reactivity with the anti-C. dubliniensis adsorbed serum are mostly expressed within the cell walls of these yeast species, and this reactivity does not interfere with the use of the anti-C. dubliniensis adsorbed serum in an indirect immunofluorescence test for the rapid identification of C. dubliniensis. PMID:9705368

  20. Genomics and the making of yeast biodiversity.

    PubMed

    Hittinger, Chris Todd; Rokas, Antonis; Bai, Feng-Yan; Boekhout, Teun; Gonçalves, Paula; Jeffries, Thomas W; Kominek, Jacek; Lachance, Marc-André; Libkind, Diego; Rosa, Carlos A; Sampaio, José Paulo; Kurtzman, Cletus P

    2015-12-01

    Yeasts are unicellular fungi that do not form fruiting bodies. Although the yeast lifestyle has evolved multiple times, most known species belong to the subphylum Saccharomycotina (syn. Hemiascomycota, hereafter yeasts). This diverse group includes the premier eukaryotic model system, Saccharomyces cerevisiae; the common human commensal and opportunistic pathogen, Candida albicans; and over 1000 other known species (with more continuing to be discovered). Yeasts are found in every biome and continent and are more genetically diverse than angiosperms or chordates. Ease of culture, simple life cycles, and small genomes (∼10-20Mbp) have made yeasts exceptional models for molecular genetics, biotechnology, and evolutionary genomics. Here we discuss recent developments in understanding the genomic underpinnings of the making of yeast biodiversity, comparing and contrasting natural and human-associated evolutionary processes. Only a tiny fraction of yeast biodiversity and metabolic capabilities has been tapped by industry and science. Expanding the taxonomic breadth of deep genomic investigations will further illuminate how genome function evolves to encode their diverse metabolisms and ecologies. PMID:26649756

  1. Candida Infections, Causes, Targets, and Resistance Mechanisms: Traditional and Alternative Antifungal Agents

    PubMed Central

    Spampinato, Claudia

    2013-01-01

    The genus Candida includes about 200 different species, but only a few species are human opportunistic pathogens and cause infections when the host becomes debilitated or immunocompromised. Candida infections can be superficial or invasive. Superficial infections often affect the skin or mucous membranes and can be treated successfully with topical antifungal drugs. However, invasive fungal infections are often life-threatening, probably due to inefficient diagnostic methods and inappropriate initial antifungal therapies. Here, we briefly review our current knowledge of pathogenic species of the genus Candida and yeast infection causes and then focus on current antifungal drugs and resistance mechanisms. An overview of new therapeutic alternatives for the treatment of Candida infections is also provided. PMID:23878798

  2. Species distribution & antifungal susceptibility pattern of oropharyngeal Candida isolates from human immunodeficiency virus infected individuals

    PubMed Central

    Das, Partha Pratim; Saikia, Lahari; Nath, Reema; Phukan, Sanjib Kumar

    2016-01-01

    Background & objectives: The changing spectrum of Candida species in causation of oropharyngeal candidiasis and their antifungal susceptibility pattern among the HIV infected individuals has made the identification to species level mandatory and detection of drug resistance necessary for patient care. The present study was carried out to determine the species distribution and antifungal susceptibility profile of oral Candida isolates colonizing or infecting both HIV seropositive and seronegative individuals. Methods: A case-control study was conducted including 141 consecutive, non-repeat HIV-seropositive individuals and an equal number of sex and age matched HIV-seronegative control. Speciation of the oropharyngeal Candida isolates was done using standard yeast identification protocol. Antifungal susceptibility testing was done by the disk-diffusion method as well as by Fungitest method. Results: From the 59 culture positive HIV seropositive cases, 61 Candida isolates were recovered; Candida albicans (n=47, 77.0%), C. dubliniensis (n=9, 14.7%), C. parapsilosis (n=2, 3.2%), C. glabrata (n=2, 3.2%), and C. famata (n=1, 1.6%). Candida colonization in HIV-seropositive individuals was significantly higher than that of HIV-seronegative (control) group. Antifungal susceptibility testing revealed (n=6, 9.3%) C. albicans isolates resistant to voriconazole and fluconazole by disk-diffusion method whereas no resistance was seen by Fungitest method. Interpretation & conclusions: C. albicans was the commonest Candida species infecting or colonizing HIV seropositive individuals. Oropharyngeal Candida isolates had high level susceptibility to all the major antifungals commonly in use. Increased level of immunosuppression in HIV-seropositives and drug resistance of non-albicans Candida species makes identification and susceptibility testing of Candida species necessary in different geographical areas of the country. PMID:27377507

  3. Optimization of glutathione production in batch and fed-batch cultures by the wild-type and recombinant strains of the methylotrophic yeast Hansenula polymorpha DL-1

    PubMed Central

    2011-01-01

    Background Tripeptide glutathione (gamma-glutamyl-L-cysteinyl-glycine) is the most abundant non-protein thiol that protects cells from metabolic and oxidative stresses and is widely used as medicine, food additives and in cosmetic industry. The methylotrophic yeast Hansenula polymorpha is regarded as a rich source of glutathione due to the role of this thiol in detoxifications of key intermediates of methanol metabolism. Cellular and extracellular glutathione production of H. polymorpha DL-1 in the wild type and recombinant strains which overexpress genes of glutathione biosynthesis (GSH2) and its precursor cysteine (MET4) was studied. Results Glutathione producing capacity of H. polymorpha DL-1 depending on parameters of cultivation (dissolved oxygen tension, pH, stirrer speed), carbon substrate (glucose, methanol) and type of overexpressed genes of glutathione and its precursor biosynthesis during batch and fed-batch fermentations were studied. Under optimized conditions of glucose fed-batch cultivation, the glutathione productivity of the engineered strains was increased from ~900 up to ~ 2300 mg of Total Intracellular Glutathione (TIG) or GSH+GSSGin, per liter of culture medium. Meantime, methanol fed-batch cultivation of one of the recombinant strains allowed achieving the extracellular glutathione productivity up to 250 mg of Total Extracellular Glutathione (TEG) or GSH+GSSGex, per liter of the culture medium. Conclusions H. polymorpha is an competitive glutathione producer as compared to other known yeast and bacteria strains (Saccharomyces cerevisiae, Candida utilis, Escherichia coli, Lactococcus lactis etc.) with good perspectives for further improvement especially for production of extracellular form of glutathione. PMID:21255454

  4. Characterisation of Yeasts Isolated from ‘Nduja of Spilinga

    PubMed Central

    Muscolino, Daniele; Beninati, Chiara; Giuffrida, Alessandro; Ziino, Graziella; Panebianco, Antonio

    2014-01-01

    The ‘Nduja of Spilinga protected geographical indication (PGI) is a spreadable italian salami, obtained by using fat (50%), lean of pork (25%), chili pepper (25%) and NaCl, stuffed into natural pork casing. Its predominant flora is represented by yeasts, reaching at the end of seasoning values of 6 log CFU/g. Considering the need to enhance and protect traditional local products, it seemed interesting to carry out a characterisation of yeasts of the ‘Nduja of Spilinga PGI. A total of 127 strains of yeast isolated from samples of ‘Nduja of Spilinga PGI (79 strains from samples at different days of curing and 48 from samples of commerce) was subjected to morphological identification, hydrolysis of urea, lipolytic activity and identification with API 20C AUX, ID 32C and simplified identification systems. One hundred twenty three (96.8%) strains were attributable to the phylum Ascomycetes (urease-negative), the remaining 4 strains (3.2%) were Basidiomycetes (urease-positive). Debaryomyces hansenii and its anamorph shape, Candida famata, represented the most prevalent species (61.42 and 17.32% respectively), followed by Candida glabrata (8.66%), Pichia (Candida) guilliermondii (5.17%), Candida parapsilosis and Rhodotorula glutinis (1.57%). Candida catenulata, Criptococcus uniguttulatus, Rhodotorula minuta, Candida zeylanoides and Candida utilis were observed with 0.79%. The lipolytic activity was observed only in 10 strains of D. hansenii and in one of C. zeylanoides. Further investigation will contribute to the selection of indigenous strains that could be used for the creation of specific starter, useful to improve the process of characterisation of the ‘Nduja of Spilinga and also to guarantee its safety. PMID:27800341

  5. Yeast Associated with the Ambrosia Beetle, Platypus koryoensis, the Pest of Oak Trees in Korea.

    PubMed

    Yun, Yeo Hong; Suh, Dong Yeon; Yoo, Hun Dal; Oh, Man Hwan; Kim, Seong Hwan

    2015-12-01

    Oak tree death caused by symbiosis of an ambrosia beetle, Platypus koryoensis, and an ophiostomatoid filamentous fungus, Raffaelea quercus-mongolicae, has been a nationwide problem in Korea since 2004. In this study, we surveyed the yeast species associated with P. koryoensis to better understand the diversity of fungal associates of the beetle pest. In 2009, a total of 195 yeast isolates were sampled from larvae and adult beetles (female and male) of P. koryoensis in Cheonan, Goyang, and Paju; 8 species were identified by based on their morphological, biochemical and molecular analyses. Meyerozyma guilliermondii and Candida kashinagacola were found to be the two dominant species. Among the 8 species, Candida homilentoma was a newly recorded yeast species in Korea, and thus, its mycological characteristics were described. The P. koryoensis symbiont R. quercusmongolicae did not show extracelluar CM-cellulase, xylanase and avicelase activity that are responsible for degradation of wood structure; however, C. kashinagacola and M. guilliermondii did show the three extracellular enzymatic activities. Extracelluar CM-cellulase activity was also found in Ambrosiozyma sp., C. homilentoma, C. kashinagacola, and Candida sp. Extracelluar pectinase activity was detected in Ambrosiozyma sp., C. homilentoma, Candida sp., and M. guilliermondii. All the 8 yeast species displayed compatible relationships with R. quercus-mongolicae when they were co-cultivated on yeast extract-malt extract plates. Overall, our results demonstrated that P. koryoensis carries the yeast species as a symbiotic fungal associate. This is first report of yeast diversity associated with P. koryoensis. PMID:26839506

  6. Yeast Associated with the Ambrosia Beetle, Platypus koryoensis, the Pest of Oak Trees in Korea

    PubMed Central

    Yun, Yeo Hong; Suh, Dong Yeon; Yoo, Hun Dal; Oh, Man Hwan

    2015-01-01

    Oak tree death caused by symbiosis of an ambrosia beetle, Platypus koryoensis, and an ophiostomatoid filamentous fungus, Raffaelea quercus-mongolicae, has been a nationwide problem in Korea since 2004. In this study, we surveyed the yeast species associated with P. koryoensis to better understand the diversity of fungal associates of the beetle pest. In 2009, a total of 195 yeast isolates were sampled from larvae and adult beetles (female and male) of P. koryoensis in Cheonan, Goyang, and Paju; 8 species were identified by based on their morphological, biochemical and molecular analyses. Meyerozyma guilliermondii and Candida kashinagacola were found to be the two dominant species. Among the 8 species, Candida homilentoma was a newly recorded yeast species in Korea, and thus, its mycological characteristics were described. The P. koryoensis symbiont R. quercusmongolicae did not show extracelluar CM-cellulase, xylanase and avicelase activity that are responsible for degradation of wood structure; however, C. kashinagacola and M. guilliermondii did show the three extracellular enzymatic activities. Extracelluar CM-cellulase activity was also found in Ambrosiozyma sp., C. homilentoma, C. kashinagacola, and Candida sp. Extracelluar pectinase activity was detected in Ambrosiozyma sp., C. homilentoma, Candida sp., and M. guilliermondii. All the 8 yeast species displayed compatible relationships with R. quercus-mongolicae when they were co-cultivated on yeast extract-malt extract plates. Overall, our results demonstrated that P. koryoensis carries the yeast species as a symbiotic fungal associate. This is first report of yeast diversity associated with P. koryoensis. PMID:26839506

  7. Granulomatous rhinitis due to Candida parapsilosis in a cat.

    PubMed

    Lamm, Catherine G; Grune, Sterrett C; Estrada, Marko M; McIlwain, Mary B; Leutenegger, Christian M

    2013-09-01

    A 9-year-old female spayed Domestic Medium Hair cat presented to the referring veterinarian with a 2-week history of sneezing, which progressed to swelling over the nasal planum. The cat had been under veterinary care for inflammatory bowel disease and had been treated with 1.25 mg/kg prednisolone once a day for approximately 1 year. On physical examination, an approximately 2-3 mm diameter, round polypoid pink soft-tissue mass was protruding slightly from the right nostril. Through histologic examination of representative sections from the mass, there was a severe diffuse infiltrate of epithelioid macrophages and neutrophils that surrounded frequent 15-20 µm yeast organisms. A Grocott methenamine silver stain revealed the presence of pseudohyphae in addition to the previously noted yeast forms. Real-time polymerase chain reaction (PCR) for Cryptococcus neoformans, Ajellomyces dermatitidis (syn. Blastomyces dermatitidis), Coccidioides immitis, Ajellomyces capsulatus (syn. Histoplasma capsulatum), Malassezia spp., and Candida spp. was performed on the paraffin-embedded sample. The PCR for Candida spp. was positive; the product was then sequenced and was determined to be consistent with Candida parapsilosis. Following the PCR diagnosis and prior to treatment of the infection, C. parapsilosis was cultured from a nasal swab. The infection in the cat in the current report was considered opportunistic and secondary to immunosuppression, following treatment for the inflammatory bowel disease. PMID:23883665

  8. Appropriate sampling for intracellular amino acid analysis in five phylogenetically different yeasts.

    PubMed

    Bolten, Christoph J; Wittmann, Christoph

    2008-11-01

    Methanol quenching and fast filtration, the two most common sampling protocols in microbial metabolome analysis, were validated for intracellular amino acid analysis in phylogenetically different yeast strains comprising Saccharomyces cerevisiae, Kluyveromyces marxianus, Pichia pastoris, Schizosaccharomyces pombe and Zygosaccharomyces bailii. With only few exceptions for selected amino acids, all yeasts exhibited negligible metabolite leakage during quenching with 60% cold buffered methanol. Slightly higher leakage was observed with increasing methanol content in the quenching solution. Fast filtration resulted in identical levels for intracellular amino acids in all strains tested. The results clearly demonstrate the validity of both approaches for leakage-free sampling of amino acids in yeast.

  9. Systems Level Dissection of Candida Recognition by Dectins: A Matter of Fungal Morphology and Site of Infection.

    PubMed

    Rizzetto, Lisa; Weil, Tobias; Cavalieri, Duccio

    2015-08-21

    Candida albicans is an ubiquitous fungal commensal of human skin and mucosal surfaces, and at the same time a major life-threatening human fungal pathogen in immunocompromised individuals. Host defense mechanisms rely on the capacity of professional phagocytes to recognize Candida cell wall antigens. During the past decade, the host immune response to Candida was dissected in depth, highlighting the essential role of C-type lectin receptors, especially regarding the power of the Dectins' family in discriminating between the tolerated yeast-like form of Candida and its invading counterpart, the hyphae. This review focuses on the immuno-modulatory properties of the Candida morphologies and their specific interactions with the host innate immune system in different body surfaces.

  10. Candida theae sp. nov., a new anamorphic beverage-associated member of the Lodderomyces clade.

    PubMed

    Chang, Chin-Feng; Lin, Yu-Ching; Chen, Shan-Fu; Carvajal Barriga, Enrique Javier; Carvaja Barriga, Enrique Javier; Barahona, Patricia Portero; James, Stephen A; Bond, Christopher J; Roberts, Ian N; Lee, Ching-Fu

    2012-02-01

    Four strains representing a novel yeast species belonging to the genus Candida were independently isolated in Taiwan and Ecuador. Two strains (G17(T) and G31) were isolated in Taiwan, by pellet precipitation from plastic-bottled tea drinks produced in Indonesia, while two additional strains (CLQCA 10-049 and CLQCA 10-062) were recovered from ancient chicha fermentation vessels found in tombs in Quito, Ecuador. These four strains were morphologically, and phylogenetically identical to each other. No sexual reproduction was observed on common sporulation media. Large-subunit (LSU) rRNA gene sequence analysis revealed the four strains to belong to the Lodderomyces clade, closely related to members of the Candida parapsilosis species complex. The four strains, which have identical LSU D1/D2 sequences, differ from their closest phylogenetic neighbors, Candida orthopsilosis and Candida parapsilosis, by 6-9 nt substitutions, respectively. Physiologically, the four strains are similar to Candida parapsilosis, although they can be distinguished from their closest relative by the assimilation of arbutin, nitrite, and creatine. The Indonesian and Ecuadorian strain sets can also be distinguished from one another based on ITS sequencing, differing by 4 substitutions in ITS1 and 1 single nucleotide indel in ITS2. Collectively, the results indicate that the four strains represent a previously unrecognized species of Candida. The name Candida theae sp. nov. is proposed to accommodate these strains, with G-17(T) (BCRC 23242(T)=CBS 12239(T)=ATCC MYA-4746(T)) designated as the type strain.

  11. Photodynamic inactivation of virulence factors of Candida strains isolated from patients with denture stomatitis.

    PubMed

    Pereira, Cristiane Aparecida; Domingues, Nádia; Silva, Michelle Peneluppi; Costa, Anna Carolina Borges Pereira; Junqueira, Juliana Campos; Jorge, Antonio Olavo Cardoso

    2015-12-01

    Candida species are major microorganisms isolated in denture stomatitis (DS), an inflammatory process of the mucosa underlying removable dental prostheses, and express a variety of virulence factors that can increase their pathogenicity. The potential of Photodynamic inactivation (PDI) in planktonic culture, biofilms and virulence factors of Candida strains was evaluated. A total of 48 clinical Candida isolates from individuals wearing removable maxillary prostheses with DS were included in the study. The effects of erythrosine (ER, 200 μM) and a green LED (λ 532 ± 10 nm, 237 mW/cm(2) and 42.63 J/cm(2)) in a planktonic culture were evaluated. The effect of the addition of ER at a concentration of 400 μM together with a green LED was evaluated in biofilms. The virulence factors of all of the Candida strains were evaluated before and after the PDI process in cells derived from biofilm and planktonic assays. All of the Candida species were susceptible to ER and green LED. However, the biofilm structures were more resistant to PDI than the planktonic cultures. PDI also promoted slight reductions in most of the virulence factors of C. albicans and some of the Candida tropicalis strains. These results suggest that the addition of PDI is effective for reducing yeasts and may also reduce the virulence of certain Candida species and decrease their pathogenicity.

  12. Mediated amperometry reveals different modes of yeast responses to sugars.

    PubMed

    Garjonyte, Rasa; Melvydas, Vytautas; Malinauskas, Albertas

    2016-02-01

    Menadione-mediated amperometry at carbon paste electrodes modified with various yeasts (Saccharomyces cerevisiae, Candida pulcherrima, Pichia guilliermondii and Debaryomyces hansenii) was employed to monitor redox activity inside the yeast cells induced by glucose, fructose, sucrose, maltose or galactose. Continuous measurements revealed distinct modes (transient or gradually increasing) of the current development during the first 2 to 3 min after subjection to glucose, fructose and sucrose at electrodes containing S. cerevisiae and non-Saccharomyces strains. Different modes (increasing or decreasing) of the current development after yeast subjection to galactose at electrodes with S. cerevisiae or D. hansenii and at electrodes with C. pulcherrima and P. guilliermondii suggested different mechanisms of galactose assimilation.

  13. Usefulness of CHROMagar Candida Medium, Biochemical Methods--API ID32C and VITEK 2 Compact and Two MALDI-TOF MS Systems for Candida spp. Identification.

    PubMed

    Stefaniuk, Elzbieta; Baraniak, Anna; Fortuna, Monika; Hryniewicz, Waleria

    2016-01-01

    This study was conducted to compare of the yeasts identification results obtained with two new systems using the MALDI-TOF MS technique with the ones obtained using the routine identification methods of Candida spp. in clinical microbiology laboratories. All 124 Candida spp. isolates were recovered from the routine examination of clinical specimens in microbiological laboratories and collected in the Centre of Quality Control in Microbiology in Warsaw (Poland). Our findings confirm the high agreement (98%) of fungal identification using the standard, biochemistry laboratory methods and mass spectrometry technique. PMID:27282002

  14. Methanol Cannon Demonstrations Revisited.

    ERIC Educational Resources Information Center

    Dolson, David A.; And Others

    1995-01-01

    Describes two variations on the traditional methanol cannon demonstration. The first variation is a chain reaction using real metal chains. The second example involves using easily available components to produce sequential explosions that can be musical in nature. (AIM)

  15. The Methanol Multibeam Survey

    NASA Astrophysics Data System (ADS)

    Green, James A.; Cohen, R. J.; Caswell, J. L.; Fuller, G. A.; Brooks, K.; Burton, M. G.; Chrysostomou, A.; Diamond, P. J.; Ellingsen, S. P.; Gray, M. D.; Hoare, M. G.; Masheder, M. R. W.; McClure-Griffiths, N.; Pestalozzi, M.; Phillips, C.; Quinn, L.; Thompson, M. A.; Voronkov, M.; Walsh, A.; Ward-Thompson, D.; Wong-McSweeney, D.; Yates, J. A.; Cox, J.

    2007-03-01

    A new 7-beam methanol multibeam receiver is being used to survey the Galaxy for newly forming massive stars, that are pinpointed by strong methanol maser emission at 6.668 GHz. The receiver, jointly constructed by Jodrell Bank Observatory (JBO) and the Australia Telescope National Facility (ATNF), was successfully commissioned at Parkes in January 2006. The Parkes-Jodrell survey of the Milky Way for methanol masers is two orders of magnitude faster than previous systematic surveys using 30-m class dishes, and is the first systematic survey of the entire Galactic plane. The first 53 days of observations with the Parkes telescope have yielded 518 methanol sources, of which 218 are new discoveries. We present the survey methodology as well as preliminary results and analysis.

  16. Tumor necrosis factor as an autocrine and paracrine signal controlling the macrophage secretory response to Candida albicans.

    PubMed Central

    Blasi, E; Pitzurra, L; Bartoli, A; Puliti, M; Bistoni, F

    1994-01-01

    We have previously demonstrated that the hyphal form of Candida albicans (H-Candida), but not the yeast form (Y-Candida), acts as a macrophage-stimulating agent. The early response (1 to 3 h) of the macrophage cell line ANA-1 to H-Candida results in enhanced tumor necrosis factor (TNF) transcription and production. Here we show that when coincubation times are prolonged (3 to 24 h), Y-Candida also exhibits stimulatory properties. This phenomenon has been ascribed to the occurrence of the dimorphic transition, as demonstrated by microscopic evaluation of the cultures and by experiments in which both killed Y-Candida and the agerminative strain C. albicans PCA-2 failed to induce cytokine production. TNF produced in response to H-Candida acts as an autocrine and paracrine signal controlling the macrophage secretory response to C. albicans. In fact, addition of anti-TNF polyclonal antibodies to the coculture of ANA-1 macrophages and H-Candida results in a marked and time-dependent decrease of TNF transcript levels. Moreover, pretreatment of macrophages with recombinant TNF for 3 h enhances TNF and induces interleukin-1 production in response to both forms of Candida, while pretreatment for 18 h renders macrophages refractory to any stimuli. Interestingly, the kinetics of interleukin-1 transcription and secretion in response to H-Candida are delayed with respect to those of TNF. Overall, these data indicate that TNF, produced by macrophages in response to H-Candida, regulates its own production as well as that of other soluble factors, thus suggesting that this cytokine plays multiple roles in the immune mechanisms involved in Candida infection. Images PMID:8132326

  17. Candida species: new insights into biofilm formation.

    PubMed

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

    2012-06-01

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

  18. Methanol contamination in traditionally fermented alcoholic beverages: the microbial dimension.

    PubMed

    Ohimain, Elijah Ige

    2016-01-01

    Incidence of methanol contamination of traditionally fermented beverages is increasing globally resulting in the death of several persons. The source of methanol contamination has not been clearly established in most countries. While there were speculations that unscrupulous vendors might have deliberately spiked the beverages with methanol, it is more likely that the methanol might have been produced by contaminating microbes during traditional ethanol fermentation, which is often inoculated spontaneously by mixed microbes, with a potential to produce mixed alcohols. Methanol production in traditionally fermented beverages can be linked to the activities of pectinase producing yeast, fungi and bacteria. This study assessed some traditional fermented beverages and found that some beverages are prone to methanol contamination including cachaca, cholai, agave, arak, plum and grape wines. Possible microbial role in the production of methanol and other volatile congeners in these fermented beverages were discussed. The study concluded by suggesting that contaminated alcoholic beverages be converted for fuel use rather than out rightly banning the age-long traditional alcohol fermentation.

  19. Methanol contamination in traditionally fermented alcoholic beverages: the microbial dimension.

    PubMed

    Ohimain, Elijah Ige

    2016-01-01

    Incidence of methanol contamination of traditionally fermented beverages is increasing globally resulting in the death of several persons. The source of methanol contamination has not been clearly established in most countries. While there were speculations that unscrupulous vendors might have deliberately spiked the beverages with methanol, it is more likely that the methanol might have been produced by contaminating microbes during traditional ethanol fermentation, which is often inoculated spontaneously by mixed microbes, with a potential to produce mixed alcohols. Methanol production in traditionally fermented beverages can be linked to the activities of pectinase producing yeast, fungi and bacteria. This study assessed some traditional fermented beverages and found that some beverages are prone to methanol contamination including cachaca, cholai, agave, arak, plum and grape wines. Possible microbial role in the production of methanol and other volatile congeners in these fermented beverages were discussed. The study concluded by suggesting that contaminated alcoholic beverages be converted for fuel use rather than out rightly banning the age-long traditional alcohol fermentation. PMID:27652180

  20. Characterization of extracellular nucleotide metabolism in Candida albicans.

    PubMed

    Rodrigues, Lisa; Russo-Abrahão, Thais; Cunha, Rodrigo A; Gonçalves, Teresa; Meyer-Fernandes, José Roberto

    2016-01-01

    Candida albicans is the most frequent agent of human disseminated fungal infection. Ectophosphatase and ectonucleotidase activities are known to influence the infectious potential of several microbes, including other non-albicans species of Candida. With the present work we aim to characterize these ecto-enzymatic activities in C. albicans. We found that C. albicans does not have a classical ecto-5'-nucleotidase enzyme and 5'AMP is cleaved by a phosphatase instead of exclusively by a nucleotidase that also can use 3'AMP as a substrate. Moreover, these enzymatic activities are not dependent on secreted soluble enzymes and change when the yeast cells are under infection conditions, including low pH, and higher temperature and CO2 content.

  1. Candida Infections of Medical Devices

    PubMed Central

    Kojic, Erna M.; Darouiche, Rabih O.

    2004-01-01

    The number of indwelling medical devices is escalating, and an increasing proportion of device-related infections are being caused by Candida spp. Candida spp. produce biofilms on synthetic materials, which facilitates adhesion of the organisms to devices and renders them relatively refractory to medical therapy. Management of device-related Candida infections can be challenging. Removal of the infected device is generally needed to establish cure of Candida infections of medical devices. However, since the pathogenesis of Candida bloodstream infection is complicated, more studies are necessary to determine the role of catheter exchange in patients with both gastrointestinal tract mucositis and indwelling catheters. The medical and economic impact of these infections is enormous. PMID:15084500

  2. Echinocandin Resistance in Candida.

    PubMed

    Perlin, David S

    2015-12-01

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

  3. Yeast Droplets

    NASA Astrophysics Data System (ADS)

    Nguyen, Baochi; Upadhyaya, Arpita; van Oudenaarden, Alexander; Brenner, Michael

    2002-11-01

    It is well known that the Young's law and surface tension govern the shape of liquid droplets on solid surfaces. Here we address through experiments and theory the shape of growing aggregates of yeast on agar substrates, and assess whether these ideas still hold. Experiments are carried out on Baker's yeast, with different levels of expressions of an adhesive protein governing cell-cell and cell-substrate adhesion. Changing either the agar concentration or the expression of this protein modifies the local contact angle of a yeast droplet. When the colony is small, the shape is a spherical cap with the contact angle obeying Young's law. However, above a critical volume this structure is unstable, and the droplet becomes nonspherical. We present a theoretical model where this instability is caused by bulk elastic effects. The model predicts that the transition depends on both volume and contact angle, in a manner quantitatively consistent with our experiments.

  4. Candida albicans escapes from mouse neutrophils.

    PubMed

    Ermert, David; Niemiec, Maria J; Röhm, Marc; Glenthøj, Andreas; Borregaard, Niels; Urban, Constantin F

    2013-08-01

    Candida albicans, the most commonly isolated human fungal pathogen, is able to grow as budding yeasts or filamentous forms, such as hyphae. The ability to switch morphology has been attributed a crucial role for the pathogenesis of C. albicans. To mimic disseminated candidiasis in humans, the mouse is the most widely used model organism. Neutrophils are essential immune cells to prevent opportunistic mycoses. To explore potential differences between the rodent infection model and the human host, we compared the interactions of C. albicans with neutrophil granulocytes from mice and humans. We revealed that murine neutrophils exhibited a significantly lower ability to kill C. albicans than their human counterparts. Strikingly, C. albicans yeast cells formed germ tubes upon internalization by murine neutrophils, eventually rupturing the neutrophil membrane and thereby, killing the phagocyte. On the contrary, growth and subsequent escape of C. albicans are blocked inside human neutrophils. According to our findings, this blockage in human neutrophils might be a result of higher levels of MPO activity and the presence of α-defensins. We therefore outline differences in antifungal immune defense between humans and mouse strains, which facilitates a more accurate interpretation of in vivo results.

  5. [The yeast biofilm in human medicine].

    PubMed

    Růzicka, Filip; Holá, Veronika; Votava, Miroslav

    2007-08-01

    In recent years, the role of Candida yeasts as causative agents of nosocomial infections has increased. One of the important virulence factors contributing to the development of such infections is biofilm production. This virulence factor enables yeast to colonize both native surfaces and artificial implants. The most common sources of infection are patients themselves, in particular the gastrointestinal tract and skin. The vectors of exogenous yeast infections are predominantly the hands of the health personnel and contaminated medical instruments. The adhesion of yeasts to the implant surfaces is determined both by implant surface and yeast characteristics. This is followed by proliferation and production of microcolonies and extracellular matrix. The final biofilm structure is also influenced by the production of hyphae and pseudohyphae. The entire process of biofilm production is controlled by numerous regulatory systems, with the key role being played by the quorum sensing system. Like the adhered bacterial cultures, candidas growing in the form of a biofilm are highly resistant to antimicrobial therapy. Resistance of yeast biofilms to antifungals is a complex process with multiple contributing factors. These are especially increased gene expression (e.g. genes encoding the so called multidrug efflux pumps), limited penetration of substances through the extracellular matrix, inhibited cell growth and altered microenvironment in deeper biofilm layers. The concentrations of antifungals able to effectively affect the biofilm cells exceed, by several orders of magnitude, the values of conventionally determined MICs. High biofilm resistance results in ineffective antifungal therapy of biofilm infections. Therefore, if possible, the colonized implant should be removed. Conservative therapy should involve antifungals with a proven effect on the biofilm (e.g. caspofungin). The most effective measure in fighting biofilm infections is prevention, especially adhering to

  6. Candida nivariensis in comparison to different phenotypes of Candida glabrata.

    PubMed

    Swoboda-Kopeć, Ewa; Sikora, Magdalena; Golas, Marlena; Piskorska, Katarzyna; Gozdowski, Dariusz; Netsvyetayeva, Irina

    2014-12-01

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

  7. Genomic Evolution of the Ascomycete Yeasts

    SciTech Connect

    Riley, Robert; Haridas, Sajeet; Salamov, Asaf; Boundy-Mills, Kyria; Goker, Markus; Hittinger, Chris; Klenk, Hans-Peter; Lopes, Mariana; Meir-Kolthoff, Jan P.; Rokas, Antonis; Rosa, Carlos; Scheuner, Carmen; Soares, Marco; Stielow, Benjamin; Wisecaver, Jennifer H.; Wolfe, Ken; Blackwell, Meredith; Kurtzman, Cletus; Grigoriev, Igor; Jeffries, Thomas

    2015-03-16

    Yeasts are important for industrial and biotechnological processes and show remarkable metabolic and phylogenetic diversity despite morphological similarities. We have sequenced the genomes of 16 ascomycete yeasts of taxonomic and industrial importance including members of Saccharomycotina and Taphrinomycotina. Phylogenetic analysis of these and previously published yeast genomes helped resolve the placement of species including Saitoella complicata, Babjeviella inositovora, Hyphopichia burtonii, and Metschnikowia bicuspidata. Moreover, we find that alternative nuclear codon usage, where CUG encodes serine instead of leucine, are monophyletic within the Saccharomycotina. Most of the yeasts have compact genomes with a large fraction of single exon genes, and a tendency towards more introns in early-diverging species. Analysis of enzyme phylogeny gives insights into the evolution of metabolic capabilities such as methanol utilization and assimilation of alternative carbon sources.

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

    PubMed Central

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

    1983-01-01

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

  9. Evaluation of baicalein, chitosan and usnic acid effect on Candida parapsilosis and Candida krusei biofilm using a Cellavista device.

    PubMed

    Kvasnickova, Eva; Matatkova, Olga; Cejkova, Alena; Masak, Jan

    2015-11-01

    Biofilms are often the cause of chronic human infections and contaminate industrial or medical equipment. The traditional approach has been to use increasing concentrations of antibiotics, but microorganisms rapidly develop multiresistance to them. Therefore, we investigated the use of natural substances as an alternative solution. The quantification of the biofilms based on the colonized areas was measured using a Cellavista automatic microscope equipped with image analysis software. Using the Cellavista device brings new possibilities for qualification and quantification of sessile cells. In our study, this feature was documented by exploring the antifungal/anti-biofilm activity of amphotericin B, baicalein, chitosan and usnic acid against yeast biofilm formation. The influence of these substances on the formation and eradication of opportunistic pathogenic yeasts Candida parapsilosis and Candida krusei biofilms was studied in 96-well polystyrene microtiter plates. While amphotericin B was not very efficient, the use of baicalein and chitosan, even in minimum inhibitory concentrations, was found to rapidly decrease the colonized areas in the wells. The usnic acid did not display any significant antibiofilm properties even at concentration 300μgml(-1). Our results propose that Cellavista is a promising tool for the study of yeast biofilm formation and the effects of antimicrobial agents. PMID:26362224

  10. Evaluation of baicalein, chitosan and usnic acid effect on Candida parapsilosis and Candida krusei biofilm using a Cellavista device.

    PubMed

    Kvasnickova, Eva; Matatkova, Olga; Cejkova, Alena; Masak, Jan

    2015-11-01

    Biofilms are often the cause of chronic human infections and contaminate industrial or medical equipment. The traditional approach has been to use increasing concentrations of antibiotics, but microorganisms rapidly develop multiresistance to them. Therefore, we investigated the use of natural substances as an alternative solution. The quantification of the biofilms based on the colonized areas was measured using a Cellavista automatic microscope equipped with image analysis software. Using the Cellavista device brings new possibilities for qualification and quantification of sessile cells. In our study, this feature was documented by exploring the antifungal/anti-biofilm activity of amphotericin B, baicalein, chitosan and usnic acid against yeast biofilm formation. The influence of these substances on the formation and eradication of opportunistic pathogenic yeasts Candida parapsilosis and Candida krusei biofilms was studied in 96-well polystyrene microtiter plates. While amphotericin B was not very efficient, the use of baicalein and chitosan, even in minimum inhibitory concentrations, was found to rapidly decrease the colonized areas in the wells. The usnic acid did not display any significant antibiofilm properties even at concentration 300μgml(-1). Our results propose that Cellavista is a promising tool for the study of yeast biofilm formation and the effects of antimicrobial agents.

  11. Vaginal Yeast Infections

    MedlinePlus

    ... 2010). Candida Infections of the Genitourinary Tract . Clinical Microbiology Reviews; 23(2): 253–273. National Institute of ... 2010). Candida Infections of the Genitourinary Tract . Clinical Microbiology Reviews; 23(2): 253–273. National Institute of ...

  12. Yeast cell factories for fine chemical and API production

    PubMed Central

    Pscheidt, Beate; Glieder, Anton

    2008-01-01

    This review gives an overview of different yeast strains and enzyme classes involved in yeast whole-cell biotransformations. A focus was put on the synthesis of compounds for fine chemical and API (= active pharmaceutical ingredient) production employing single or only few-step enzymatic reactions. Accounting for recent success stories in metabolic engineering, the construction and use of synthetic pathways was also highlighted. Examples from academia and industry and advances in the field of designed yeast strain construction demonstrate the broad significance of yeast whole-cell applications. In addition to Saccharomyces cerevisiae, alternative yeast whole-cell biocatalysts are discussed such as Candida sp., Cryptococcus sp., Geotrichum sp., Issatchenkia sp., Kloeckera sp., Kluyveromyces sp., Pichia sp. (including Hansenula polymorpha = P. angusta), Rhodotorula sp., Rhodosporidium sp., alternative Saccharomyces sp., Schizosaccharomyces pombe, Torulopsis sp., Trichosporon sp., Trigonopsis variabilis, Yarrowia lipolytica and Zygosaccharomyces rouxii. PMID:18684335

  13. [Influence of slime production and adhesion of Candida sp. on biofilm formation].

    PubMed

    Ciok-Pater, Emilia; Smolak, Przemysław; Wróblewska, Joanna; Gospodarek, Eugenia

    2011-01-01

    The increase of fungal infections in recent years is connected with the progress in medicine. The vast usage of biomaterials is an inseparable element of contemporary medicine but it also leads to development of infections. Yeast-like fungi Candida albicans are still the main pathogen of candidiasis. The ability to slime production and adhesion to polystyrene of Candida sp. on different surfaces can cause to form biofilm on surfaces of biomaterials used in production of catheters, drains and prosthesis. The aim of the study was to evaluate the influence of slime production and adhesion to polystyrene, of Candida sp. on biofilm formation on different biomaterials. 50 strains of Candida sp. were examined. They isolated from ill to Clinics of Anesthesiology and Intensive Therapy University Hospital No 1 of dr. A. Jurasza in Bydgoszcz. The ability to slime production was evaluated by Christensen method in modification Davenport and Branchini methods. The adhesion to polystyrene was evaluated by Richards et el method. The ability to produce biofilm biomaterials by the studied fungi was measured after 72 hours of incubation at 37 degrees C on different biomaterials. Yeast-like fungi Candida sp. fabricating slime and adhesion forming frequently biofilm on surface researched of biomaterials. Influence of chosen biological specificity ascertain on the ability to produce biofilm on surfaces of siliconized latex and polyvinylchloride.

  14. [Isolated yeast species in urine samples in a Spanish regional hospital].

    PubMed

    Heras-Cañas, Victor; Ros, Luis; Sorlózano, Antonio; Gutiérrez-Soto, Blanca; Navarro-Marí, José María; Gutiérrez-Fernández, José

    2015-01-01

    Candiduria detection in hospitalized or immunocompromised patients is of great clinical significance. The aim of our study was to describe the isolation frequency of significant species of yeasts in urine samples processed in our hospital during the period 2010- 2013, and to analyze their susceptibility to commonly used antifungal agents. Species identification was performed by seeding on a chromogenic medium, the filamentation test and automated systems (ASM Vitek and MALDI Biotyper), while susceptibility was determined using the ASM Vitek system. Of the 632 yeast isolates in urine, 371 were Candida albicans species and 261 non-C. albicans Candida spp. The species with the highest number of resistant isolates were Candida glabrata and Candida krusei. Based on the results obtained, we believe that species identification and the susceptibility study should be current practice in the laboratories when species other than C. albicans are isolated.

  15. Effects of simulated microgravity by RCCS on the biological features of Candida albicans.

    PubMed

    Jiang, Wenjun; Xu, Bingxin; Yi, Yong; Huang, Yuling; Li, Xiao-Ou; Jiang, Fuquan; Zhou, Jinlian; Zhang, Jianzhong; Cui, Yan

    2014-01-01

    During the spaceflight, a wide variety of microorganisms may be carried to the outer space by astronauts and aviation component. The yeast Candida albicans is an important opportunistic pathogen responsible for a variety of cutaneous and systemic human infections in human body, and the yeast cell itself could be affected by various stressful environmental factors including the weightless environment. We evaluated the effects of simulated microgravity on biological features of Candida albicans using the rotary cell culture system (RCCS). The growth curves of Candida albicans cultured in RCCS were recorded by spectrophotometer, the morphogenic switches were observed by optical microscope, and the viability of cells exposed to the various concentrations of fluconazole solution was assayed by flow cytometry at 7th, 14th and 21st day of experiment. The results showed that Candida albicans SC5314 under modeled microgravity were manifested as the growth curves leftward-shifted, lag phase shortened, along with logarithmic phase and stationary phase forwarded (P < 0.05). The simulated microgravity increased the growth rate and mycelia formation of Candida albicans. A statistically significant decrease in viability was detected in cells cultured for 7 d, 14 d and 21 d in group of simulated microgravity compared with the control group (P < 0.05). The increase of exposure time to simulate microgravity resulted in the decrease of viability of cells accordingly in same drug concentration compared with the control group. The study demonstrated that the three weeks' simulated microgravity in RCCS had a noticeable affect on the growth status of mycelia and spores and the morphogenic switches of Candida albicans, meanwhile, the yeast cells under simulated microgravity showed an increased antifungal susceptibility to fluconazole. PMID:25120754

  16. NADPH oxidase of human dendritic cells: role in Candida albicans killing and regulation by interferons, dectin-1 and CD206.

    PubMed

    Donini, Marta; Zenaro, Elena; Tamassia, Nicola; Dusi, Stefano

    2007-05-01

    Human monocyte-derived DC express the enzyme NADPH oxidase, responsible for ROS production. We show that Candida albicans did not activate NADPH oxidase in DC, and was poorly killed by these cells. However, Candida-killing activity increased upon DC stimulation with the NADPH oxidase activator PMA and was further enhanced by DC treatment with IFN-alpha or IFN-gamma. This fungicidal activity took place at high DC-to-Candida ratio, but decreased at low DC-to-yeast ratio, when Candida inhibited the NADPH oxidase by contrasting the assembly of the enzyme on DC plasma membrane. The NADPH oxidase inhibitor diphenyliodonium chloride abrogated the PMA-dependent DC candidacidal capacity. Engagement of beta-glucan receptor dectin-1 induced NADPH oxidase activation in DC that was depressed by mannose-binding receptor CD206 co-stimulation. Candida was internalized by DC through mannose-binding receptors, but not through dectin-1, thus explaining why Candida did not elicit NADPH oxidase activity. Our results indicate that NADPH oxidase is involved in DC Candida-killing activity, which is increased by IFN. However, Candida escapes the oxidative damage by inhibiting NADPH oxidase and by entering DC through receptors not involved in NADPH oxidase activation. PMID:17407098

  17. Methanol in dark clouds

    NASA Technical Reports Server (NTRS)

    Friberg, P.; Hjalmarson, A.; Madden, S. C.; Irvine, W. M.

    1988-01-01

    The first observation of methanol in cold dark clouds TMC 1, L 134 N, and B 335 is reported. In all three clouds, the relative abundance of methanol was found to be in the range of 10 to the -9th (i.e., almost an order of magnitude more abundant than acetaldehyde), with no observable variation between the clouds. Methanol emission showed a complex velocity structure; in TMC 1, clear indications of non-LTE were observed. Dimethyl ether was searched for in L 134 N; the upper limit of the column density of dimethyl ether in L 134 N was estimated to be 4 x 10 to the 12th/sq cm, assuming 5 K rotation temperature and LTE. This limit makes the abundance ratio (CH3)2O/CH3OH not higher than 1/5, indicating that dimethyl ether is not overabundant in this dark cloud.

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

    USGS Publications Warehouse

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

    1974-01-01

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

  19. [Candida and Saccharomyces spp. fungal associations in fecal microbiocenosis of diabetes patients and healthy subjects].

    PubMed

    Gerasimova, E V; Nesvizhskiĭ, Iu V; Maĭorova, N M; Bogdanova, E A

    2010-01-01

    The article is devoted to analysis of pathogenic and diagnostic significance of Candida and Saccharomyces co-existence in diabetic patients. These transient fungi are known to be present in fecal microbiocenosis of both healthy subjects and patients with diabetes mellitus. However, their overall occurrence is significantly increased in the disease and the structure of the biocenosis undergoes alteration. These data confirm the role of yeast-like fungi in pathogenesis of diabetes. The diagnostic value of detection of monospecific and mixed populations of Candida and Saccharomyces spp. is not very high, but their presence in feces, especially in women, may be regarded as a sign of disturbed carbohydrate metabolism. PMID:21395061

  20. Candida famata mediastinitis. A rare complication of open heart surgery. Case report and brief review.

    PubMed

    Sanchez Betancourt, Alfredo Alonso; Sibaja Alvarez, Pablo; Camacho, Rolando Arguedas; Guevara Espinoza, Edward

    2016-01-01

    Candida mediastinitis is a rare complication of open heart surgery with high mortality and morbidity usually associated with C. albicans. We are reporting the case of a 57 year old male who after having a triple coronary artery bypass graft procedure, had mediastinitis caused by Candida famata, a yeast, that had only been reported once before as the causal agent of this condition. It is of vital importance, that future cases be reported, due to the fact that both reported cases have led to patient demise. PMID:27419075

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

    PubMed Central

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

    1997-01-01

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

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

    PubMed

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

    2011-12-01

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

  3. Formic acid and acetic acid induce a programmed cell death in pathogenic Candida species.

    PubMed

    Lastauskienė, Eglė; Zinkevičienė, Auksė; Girkontaitė, Irutė; Kaunietis, Arnoldas; Kvedarienė, Violeta

    2014-09-01

    Cutaneous fungal infections are common and widespread. Antifungal agents used for the treatment of these infections often have undesirable side effects. Furthermore, increased resistance of the microorganisms to the antifungal drugs becomes the growing problem. Accordingly, the search for natural antifungal compounds continues to receive attention. Apoptosis is highly regulated programmed cell death. During yeast cell apoptosis, amino acids and peptides are released and can stimulate regeneration of human epithelium cells. Thus, detection of chemical compounds inducing apoptosis in yeast and nontoxic for humans is of great medical relevance. The aim of this study was to detect chemical compound inducing apoptosis in pathogenic Candida species with the lowest toxicity to the mammalian cells. Five chemical compounds--acetic acid, sodium bicarbonate, potassium carbonate, lithium acetate, and formic acid--were tested for evaluation of antifungal activity on C. albicans, C. guilliermondii, and C. lusitaniae. The results showed that acetic acid and formic acid at the lowest concentrations induced yeast cells death. Apoptosis analysis revealed that cells death was accompanied by activation of caspase. Minimal inhibitory concentrations of potassium carbonate and sodium bicarbonate induced Candida cells necrosis. Toxicity test with mammalian cell cultures showed that formic acid has the lowest effect on the growth of Jurkat and NIH 3T3 cells. In conclusion, our results show that a low concentration of formic acid induces apoptosis-like programmed cell death in the Candida yeast and has a minimal effect on the survivability of mammalian cells, suggesting potential applications in the treatment of these infections. PMID:24752490

  4. Chromogenic medium for direct susceptibility testing of Candida spp. isolated from urine.

    PubMed

    de Vasconcelos, Antônio Alexandre; Menezes, Everardo Albuquerque; Cunha, Francisco Afrânio

    2011-08-01

    Currently, there has been an increased frequency of fungal infections. Candida albicans and other Candida spp. have been proven to be major causes for urinary tract infection. Increased resistance to antifungals indicates the need to develop strategies in order to prevent the spread of resistance. Chromogenic medium have been proven to be useful in the detection of yeasts in clinical specimens containing mixed cultures of Candida. The aim of this study was to compare the results of antifungal susceptibility testing with fluconazole and amphotericin B on strains of Candida spp. isolated from urine, conducted on a Mueller-Hinton Agar with Glucose and Methylene Blue (MHAGMB) medium and on a Hicrome Candida® Agar with 2% Glucose (HCAG) medium. We used 40 samples of Candida spp. isolated from urine samples from inpatients and outpatients. The results showed that both media presented high rates of agreement, above 94%. The use of the HCAG medium decreases the release time of the results by 24-48 h, which may be decisive for initiating the correct drug treatment.

  5. Simvastatin inhibits planktonic cells and biofilms of Candida and Cryptococcus species.

    PubMed

    Brilhante, Raimunda Sâmia Nogueira; Caetano, Erica Pacheco de; Oliveira, Jonathas Sales; Castelo-Branco, Débora de Souza Collares Maia; Souza, Elizabeth Ribeiro Yokobatake; Alencar, Lucas Pereira de; Cordeiro, Rossana de Aguiar; Bandeira, Tereza de Jesus Pinheiro Gomes; Sidrim, José Júlio Costa; Rocha, Marcos Fábio Gadelha

    2015-01-01

    The antifungal activity of some statins against different fungal species has been reported. Thus, at the first moment, the in vitro antifungal activity of simvastatin, atorvastatin and pravastatin was tested against Candida spp. and Cryptococcus spp. Then, in a second approach, considering that the best results were obtained for simvastatin, this drug was evaluated in combination with antifungal drugs against planktonic growth and tested against biofilms of Candida spp. and Cryptococcus spp. Drug susceptibility testing was performed using the microdilution broth method, as described by the Clinical and Laboratory Standards Institute. The interaction between simvastatin and antifungals against planktonic cells was analyzed by calculating the fractional inhibitory concentration index. Regarding biofilm susceptibility, simvastatin was tested against growing biofilm and mature biofilm of one strain of each tested yeast species. Simvastatin showed inhibitory effect against Candida spp. and Cryptococcus spp. with minimum inhibitory concentration values ranging from 15.6 to 1000 mg L(-1) and from 62.5 to 1000 mg L(-1), respectively. The combination of simvastatin with itraconazole and fluconazole showed synergism against Candida spp. and Cryptococcus spp., while the combination of simvastatin with amphotericin B was synergistic only against Cryptococcus spp. Concerning the biofilm assays, simvastatin was able to inhibit both growing biofilm and mature biofilm of Candida spp. and Cryptococcus spp. The present study showed that simvastatin inhibits planktonic cells and biofilms of Candida and Cryptococcus species.

  6. Occurrence, isolation and differentiation of Candida spp. and prevalence of variables associated to chronic atrophic candidiasis.

    PubMed

    Lund, Rafael Guerra; da Silva Nascente, Patrícia; Etges, Adriana; Ribeiro, Gladis Aver; Rosalen, Pedro Luiz; Del Pino, Francisco Augusto Burkert

    2010-05-01

    The purpose of this study was to survey the frequency of Candida spp. in patients with chronic atrophic candidiasis (CAC), to differentiate Candida species and to assess the prevalence of certain infection-associated variables to this disease. Patients with CAC and wearing partial or complete dentures were recruited. Data were obtained by means of a questionnaire with details involving identification of the subject, demographic characteristics, behaviour and medical history, clinical and mycological evaluation and identification of yeast. The sample collection was carried out in the palate or palate and tongue of the subjects using sterilised swabs. Data were submitted to statistical analyses using Fischer's test. Forty-three (53%) cases of CAC showed the presence of Candida albicans. Females (75.2%) wearing complete dentures (60.1%) for more than 10 years (58%) were risk factors to CAC development. It could be concluded that: (a) the results did not confirm a significant difference among patients with CAC concerning the presence or absence of Candida spp.; (b) the occurrence of Candida was negatively related to important factors associated to this opportunistic infection; and (c) mycological findings did not indicate that the variables investigated have a significant effect on oral infections by C. albicans or other Candida species.

  7. Lethal otogenic Candida meningitis.

    PubMed

    Koch, S; Rudel, B; Tietz, H-J

    2004-10-01

    History revealed a chronic obstructive pulmonary condition which had been treated with prednisolone for a long time. There was a raised temperature with further signs of an acute inflammatory underlying disease and internal hydrocephalus. After performing trepanation, the symptoms of raised intercerebral pressure ceased. Candida albicans could be detected microbiologically in the cerebrospinal fluid. There was no pneumonia at the time of admission. Despite instituting immediate intensive care with administration of antibiotics and antimycotics, the patient died 11 days after inpatient admission. Autopsy revealed a C. albicans mycosis originating from the right middle ear with extensive suppurative meningitis, which was the immediate cause of death. Confluent bronchopneumonia had developed in both lower lung lobes at the time of death, but did not show any signs of mycosis and had contributed indirectly to the death of the patient.

  8. [Determination of Candida colonization and Candida score in patients in anesthesia intensive care unit].

    PubMed

    Gökahmetoğlu, Günhan; Mutlu Sarıgüzel, Fatma; Koç, Ayşe Nedret; Behret, Orhan; Gökahmetoğlu, Selma; Atalay, Mustafa Altay; Elmalı, Ferhan; Darçın, Kamil

    2016-07-01

    The colonization rate of Candida spp. reaches up to 80% in patients who reside in intensive care units (ICUs) more than a week, and the mean rate of development of invasive disease is 10% in colonized patients. Since invasive candidiasis (IC) in ICU patients presents with septic shock and high mortality rate, rapid diagnosis and treatment are crucial. The aim of this study was to assess the relationship between invasive infection and the determination of Candida colonization index (CI) and Candida score (CS) in patients admitted to ICU who are at high risk for IC and likely to benefit from early antifungal therapy. A total of 80 patients (34 female, 46 male; age range: 12-92 years, mean age: 69.57 ± 16.30) who were in ICU over seven days or longer of Anesthesia Department of Kayseri Education and Research Hospital between April, 2014 and July, 2015 were included in the study. None of the patients were neutropenic. After admission, throat, nose, skin (axillary region), urine, rectal swab and blood cultures have been collected weekly beginning from day zero. Isolation and identification of Candida strains were performed by using conventional mycological methods. CI was calculated as the ratio of the number of culture-positive distinct body sites (except blood culture) to the total number of body sites cultured. CI> 0.2 was considered as fungal colonization, while CI≥ 0.5 as intensive colonization. CS value was calculated according to the components including total parenteral nutrition (TPN) (plus 0.908 points), surgery (plus 0.907 points), colonization in multiple areas (plus 1.112) and severe sepsis (plus 2.038 points), and cut-off value for CS was accepted as >2.5. In our study, overall 1009 cultures (mean: 13 cultures per patient) were taken from 80 patients, and yeast growth was detected in 365 (36.2%) of them. Accordingly, among 68 (85%) of 80 patients included, in at least one sample, yeast growth was determined. No yeast growth was observed in the blood

  9. [Determination of Candida colonization and Candida score in patients in anesthesia intensive care unit].

    PubMed

    Gökahmetoğlu, Günhan; Mutlu Sarıgüzel, Fatma; Koç, Ayşe Nedret; Behret, Orhan; Gökahmetoğlu, Selma; Atalay, Mustafa Altay; Elmalı, Ferhan; Darçın, Kamil

    2016-07-01

    The colonization rate of Candida spp. reaches up to 80% in patients who reside in intensive care units (ICUs) more than a week, and the mean rate of development of invasive disease is 10% in colonized patients. Since invasive candidiasis (IC) in ICU patients presents with septic shock and high mortality rate, rapid diagnosis and treatment are crucial. The aim of this study was to assess the relationship between invasive infection and the determination of Candida colonization index (CI) and Candida score (CS) in patients admitted to ICU who are at high risk for IC and likely to benefit from early antifungal therapy. A total of 80 patients (34 female, 46 male; age range: 12-92 years, mean age: 69.57 ± 16.30) who were in ICU over seven days or longer of Anesthesia Department of Kayseri Education and Research Hospital between April, 2014 and July, 2015 were included in the study. None of the patients were neutropenic. After admission, throat, nose, skin (axillary region), urine, rectal swab and blood cultures have been collected weekly beginning from day zero. Isolation and identification of Candida strains were performed by using conventional mycological methods. CI was calculated as the ratio of the number of culture-positive distinct body sites (except blood culture) to the total number of body sites cultured. CI> 0.2 was considered as fungal colonization, while CI≥ 0.5 as intensive colonization. CS value was calculated according to the components including total parenteral nutrition (TPN) (plus 0.908 points), surgery (plus 0.907 points), colonization in multiple areas (plus 1.112) and severe sepsis (plus 2.038 points), and cut-off value for CS was accepted as >2.5. In our study, overall 1009 cultures (mean: 13 cultures per patient) were taken from 80 patients, and yeast growth was detected in 365 (36.2%) of them. Accordingly, among 68 (85%) of 80 patients included, in at least one sample, yeast growth was determined. No yeast growth was observed in the blood

  10. Yeast ecology in French cider and black olive natural fermentations.

    PubMed

    Coton, Emmanuel; Coton, Monika; Levert, Delphine; Casaregola, Serge; Sohier, Danièle

    2006-04-15

    In this study, rDNA ITS restriction analysis was used to identify yeasts from two naturally fermented products: French ciders and black olives. In cider musts and bottled ciders, the PCR-RFLP method generated 15 different ITS/RFLP profiles for a total of 208 isolates. The predominant yeasts corresponded to Saccharomyces bayanus, Saccharomyces cerevisiae, Lachancea cidri and Dekkera anomala. Three identified species: Candida sake, Candida tropicalis and Kluyveromyces marxianus had never been described before in ciders. For the black olive fermentation, the method allowed for identification of 11 profiles for a total of 137 isolates. A sequential apparition of yeasts was observed with Pichia anomala, Candida boidinii and Debaryomyces etchellsii being the predominant species. Four isolates did not correspond to any known species based on the sequencing of the D1/D2 region of the 26S rRNA gene. By using the rDNA ITS method, valuable information on yeast population biodiversity and dynamics in the naturally fermented food products studied was obtained. PMID:16380183

  11. Methanol from coal

    NASA Technical Reports Server (NTRS)

    Miller, D. R.

    1978-01-01

    Economic feasibility of methanol or methyl fuel produced from coal using existing technology is discussed. Other factors considered include environmental, safety, toxicity, transportation, so storage, ease of burning, and retrofitting of present boilers. Demonstrations of its uses as a boiler fuel and as a turbine fuel are cited.

  12. In vitro activity of essential oils extracted from plants used as spices against fluconazole-resistant and fluconazole-susceptible Candida spp.

    PubMed

    Pozzatti, Patrícia; Scheid, Liliane Alves; Spader, Tatiana Borba; Atayde, Margareth Linde; Santurio, Janio Morais; Alves, Sydney Hartz

    2008-11-01

    In the present study, the antifungal activity of selected essential oils obtained from plants used as spices was evaluated against both fluconazole-resistant and fluconazole-susceptible Candida spp. The Candida species studied were Candida albicans, Candida dubliniensis, Candida tropicalis, Candida glabrata, and Candida krusei. For comparison purposes, they were arranged in groups as C. albicans, C. dubliniensis, and Candida non-albicans. The essential oils were obtained from Cinnamomum zeylanicum Breyn, Lippia graveolens HBK, Ocimum basilicum L., Origanum vulgare L., Rosmarinus officinalis L., Salvia officinalis L., Thymus vulgaris L., and Zingiber officinale. The susceptibility tests were based on the M27-A2 methodology. The chemical composition of the essential oils was obtained by gas chromatography-mass spectroscopy and by retention indices. The results showed that cinnamon, Mexican oregano, oregano, thyme, and ginger essential oils have different levels of antifungal activity. Oregano and ginger essential oils were found to be the most and the least efficient, respectively. The main finding was that the susceptibilities of fluconazole-resistant C. albicans, C. dubliniensis, and Candida non-albicans to Mexican oregano, oregano, thyme, and ginger essential oils were higher than those of the fluconazole-susceptible yeasts (P<0.05). In contrast, fluconazole-resistant C. albicans and Candida non-albicans were less susceptible to cinnamon essential oil than their fluconazole-susceptible counterparts (P<0.05). A relationship between the yeasts' susceptibilities and the chemical composition of the essential oils studied was apparent when these 2 parameters were compared. Finally, basil, rosemary, and sage essential oils did not show antifungal activity against Candida isolates at the tested concentrations. PMID:18997851

  13. Biomarkers to evaluate the effects of temperature and methanol on recombinant Pichia pastoris

    PubMed Central

    Zepeda, Andrea B.; Figueroa, Carolina A.; Abdalla, Dulcineia S.P.; Maranhão, Andrea Q.; Ulloa, Patricio H.; Pessoa, Adalberto; Farías, Jorge G.

    2014-01-01

    Pichia pastoris is methylotrophic yeast used as an efficient expression system for heterologous protein production. In order to evaluate the effects of temperature (10 and 30 °C) and methanol (1 and 3% (v/v)) on genetically-modified Pichia pastoris, different biomarkers were evaluated: Heat stress (HSF-1 and Hsp70), oxidative stress (OGG1 and TBARS) and antioxidant (GLR). Three yeast cultures were performed: 3X = 3% methanol-10 °C, 4X = 3% methanol-30 °C, and 5X = 1% methanol-10°C. The expression level of HIF-1α, HSF-1, HSP-70 and HSP-90 biomarkers were measured by Western blot and in situ detection was performed by immunocytochemistry. Ours results show that at 3% methanol −30 °C there is an increase of mitochondrial OGG1 (mtOGG1), Glutathione Reductase (GLR) and TBARS. In addition, there was a cytosolic expression of HSF-1 and HSP-70, which indicates a deprotection against nucleolar fragmentation (apoptosis). On the other hand, at 3% methanol −10 °C and 1% and at methanol −10 °C conditions there was nuclear expression of OGG1, lower levels of TBARS and lower expression of GLR, cytosolic expression of HSF-1 and nuclear expression HSP-70. In conclusion, our results suggest that 3% methanol-30 °C is a condition that induces a strong oxidative stress and risk factors of apoptosis in modified-genetically P. pastoris. PMID:25242930

  14. Biomarkers to evaluate the effects of temperature and methanol on recombinant Pichia pastoris.

    PubMed

    Zepeda, Andrea B; Figueroa, Carolina A; Abdalla, Dulcineia S P; Maranhão, Andrea Q; Ulloa, Patricio H; Pessoa, Adalberto; Farías, Jorge G

    2014-01-01

    Pichia pastoris is methylotrophic yeast used as an efficient expression system for heterologous protein production. In order to evaluate the effects of temperature (10 and 30 °C) and methanol (1 and 3% (v/v)) on genetically-modified Pichia pastoris, different biomarkers were evaluated: Heat stress (HSF-1 and Hsp70), oxidative stress (OGG1 and TBARS) and antioxidant (GLR). Three yeast cultures were performed: 3X = 3% methanol-10 °C, 4X = 3% methanol-30 °C, and 5X = 1% methanol-10°C. The expression level of HIF-1α, HSF-1, HSP-70 and HSP-90 biomarkers were measured by Western blot and in situ detection was performed by immunocytochemistry. Ours results show that at 3% methanol -30 °C there is an increase of mitochondrial OGG1 (mtOGG1), Glutathione Reductase (GLR) and TBARS. In addition, there was a cytosolic expression of HSF-1 and HSP-70, which indicates a deprotection against nucleolar fragmentation (apoptosis). On the other hand, at 3% methanol -10 °C and 1% and at methanol -10 °C conditions there was nuclear expression of OGG1, lower levels of TBARS and lower expression of GLR, cytosolic expression of HSF-1 and nuclear expression HSP-70. In conclusion, our results suggest that 3% methanol-30 °C is a condition that induces a strong oxidative stress and risk factors of apoptosis in modified-genetically P. pastoris. PMID:25242930

  15. Antifungal Susceptibility Profiles of Bloodstream Yeast Isolates by Sensititre YeastOne over Nine Years at a Large Italian Teaching Hospital

    PubMed Central

    Posteraro, Brunella; Spanu, Teresa; Fiori, Barbara; De Maio, Flavio; De Carolis, Elena; Giaquinto, Alessia; Prete, Valentina; De Angelis, Giulia; Torelli, Riccardo; D'Inzeo, Tiziana; Vella, Antonietta; De Luca, Alessio; Tumbarello, Mario; Ricciardi, Walter

    2015-01-01

    Sensititre YeastOne (SYO) is an affordable alternative to the Clinical and Laboratory Standards Institute (CLSI) reference method for antifungal susceptibility testing. In this study, the MICs of yeast isolates from 1,214 bloodstream infection episodes, generated by SYO during hospital laboratory activity (January 2005 to December 2013), were reanalyzed using current CLSI clinical breakpoints/epidemiological cutoff values to assign susceptibility (or the wild-type [WT] phenotype) to systemic antifungal agents. Excluding Candida albicans (57.4% of all isolates [n = 1,250]), the most predominant species were Candida parapsilosis complex (20.9%), Candida tropicalis (8.2%), Candida glabrata (6.4%), Candida guilliermondii (1.6%), and Candida krusei (1.3%). Among the non-Candida species (1.9%), 7 were Cryptococcus neoformans and 17 were other species, mainly Rhodotorula species. Over 97% of Candida isolates were susceptible (WT phenotype) to amphotericin B and flucytosine. Rates of susceptibility (WT phenotype) to fluconazole, itraconazole, and voriconazole were 98.7% in C. albicans, 92.3% in the C. parapsilosis complex, 96.1% in C. tropicalis, 92.5% in C. glabrata, 100% in C. guilliermondii, and 100% (excluding fluconazole) in C. krusei. The fluconazole-resistant isolates consisted of 6 C. parapsilosis complex isolates, 3 C. glabrata isolates, 2 C. albicans isolates, 2 C. tropicalis isolates, and 1 Candida lusitaniae isolate. Of the non-Candida isolates, 2 C. neoformans isolates had the non-WT phenotype for susceptibility to fluconazole, whereas Rhodotorula isolates had elevated azole MICs. Overall, 99.7% to 99.8% of Candida isolates were susceptible (WT phenotype) to echinocandins, but 3 isolates were nonsusceptible (either intermediate or resistant) to caspofungin (C. albicans, C. guilliermondii, and C. krusei), anidulafungin (C. albicans and C. guilliermondii), and micafungin (C. albicans). However, when the intrinsically resistant non-Candida isolates were included

  16. Candida lusitaniae as an Unusual Cause of Recurrent Vaginitis and its Successful Treatment With Intravaginal Boric Acid

    PubMed Central

    Morgan, Margie; Nichols, W. S.

    2001-01-01

    Increasing use of short-course antifungal therapies in patients with recurrent vulvovaginitis may enable the emergence of less-common, more resistant yeast strains as vaginal pathogens. We report the case of a patient with chronically symptomatic and repeatedly treated vaginal candidiasis whose infection was attributable to Candida lusitaniae, a previously unreported cause of candidal vaginitis . PMID:11916183

  17. Draft Genome Sequence of a Fluconazole-Resistant Candida auris Strain from a Candidemia Patient in India.

    PubMed

    Sharma, Cheshta; Kumar, Nitin; Meis, Jacques F; Pandey, Rajesh; Chowdhary, Anuradha

    2015-07-16

    Candida auris is a multidrug-resistant yeast incriminated in a wide spectrum of invasive infections, especially in intensive care settings. The first draft genome sequence of C. auris, VPCI 479/P/13, from a case with fungemia was sequenced using the Illumina MiSeq platform. The estimated genome size is 12.3 Mb, with 6,675 coding sequences.

  18. Microbiology and Epidemiology of Oral Yeast Colonization in Hemopoietic Progenitor Cell Transplant Recipients

    PubMed Central

    Westbrook, Steven D.; Kirkpatrick, William R.; Wiederhold, Nathan P.; Freytes, Cesar O.; Toro, Juan J.; Patterson, Thomas F.; Redding, Spencer W.

    2012-01-01

    Objective We monitored the epidemiology and microbiology of oral yeast colonization in patients undergoing hemopoietic progenitor cell transplantation (HPCT) to examine associations between yeast colonization and oral mucositis. Study Design One hundred twenty-one consecutive HPCT patients were sampled for oral yeasts prior to fluconazole (FLC) prophylaxis, at transplant, and weekly until discharge. Clinical oral mucositis screenings were performed tri-weekly. Results Yeast colonization was evident at 216 of 510 total visits. Candida albicans and C. glabrata were the predominate organisms. Eight patients showed elevated MICs to FLC. One patient developed fungal septicemia. Patients with OMAS mucositis scores <20 had higher colonization rates than those with higher scores. Conclusions FLC is very effective in controlling a variety of oral yeasts in HPCT recipients. FLC resistant yeasts do emerge and can be the source of fungal sepsis. A positive association was not shown between yeast colonization and presence or severity of oral mucositis. PMID:23312542

  19. Ecology of pathogenic yeasts in Amazonian soil.

    PubMed Central

    Mok, W Y; Luizão, R C; do Socorro Barreto da Silva, M; Teixeira, M F; Muniz, E G

    1984-01-01

    In an investigation of Amazonian soil as a natural reservoir for pathogenic fungi, 1,949 soil samples collected from diverse geographical and ecological settings of the Brazilian Amazon Basin were analyzed for the presence of non-keratinophilic fungi by the indirect mouse inoculation procedure and for the presence of keratinophilic fungi by the hair bait technique. All soil samples were acidic with low pH values. From 12% of the soil samples, 241 yeast and yeastlike isolates pertaining to six genera and 82 species were recovered, of which 63% were Torulopsis and 26% were Candida species. Nine fungi with known pathogenic potentials were encountered among 43% (104) of the isolates: T. glabrata, C. guilliermondii, C. albicans, C. pseudotropicalis, C. stellatoidea, C. tropicalis, Rhodotorula rubra, and Wangiella dermatitidis. The yeast flora was marked by species diversity, low frequency of each species, random geographical distribution, and an apparent lack of species clustering. The composition and distribution of the yeast flora in soil differed from those of the yeast flora harbored by bats, suggesting that the Amazonian external environment and internal bat organs act as independent natural habitats for yeasts. PMID:6538774

  20. Antifungal Susceptibility in Serum and Virulence Determinants of Candida Bloodstream Isolates from Hong Kong

    PubMed Central

    Seneviratne, Chaminda J.; Rajan, Suhasini; Wong, Sarah S. W.; Tsang, Dominic N. C.; Lai, Christopher K. C.; Samaranayake, Lakshman P.; Jin, Lijian

    2016-01-01

    Candida bloodstream infections (CBI) are one of the most common nosocomial infections globally, and they account for a high mortality rate. The increasing global prevalence of drug-resistant Candida strains has also been posing a challenge to clinicians. In this study, we comprehensively evaluated the biofilm formation and production of hemolysin and proteinase of 63 CBI isolates derived from a hospital setting in Hong Kong as well as their antifungal susceptibility both in the presence and in the absence of human serum, using standard methodology. Candida albicans was the predominant species among the 63 CBI isolates collected, and non-albicans Candida species accounted for approximately one third of the isolates (36.5%). Of them, Candida tropicalis was the most common non-albicans Candida species. A high proportion (31.7%) of the CBI isolates (40% of C. albicans isolates, 10% of C. tropicalis isolates, 11% of C. parapsilosis isolates, and 100% of C. glabrata isolates) were found to be resistant to fluconazole. One of the isolates (C. tropicalis) was resistant to amphotericin B. A rising prevalence of drug-resistance CBI isolates in Hong Kong was observed with reference to a previous study. Notably, all non-albicans Candida species, showed increased hemolytic activity relative to C. albicans, whilst C. albicans, C. tropicalis, and C. parapsilosis exhibited proteinase activities. Majority of the isolates were capable of forming mature biofilms. Interestingly, the presence of serum distorted the yeast sensitivity to fluconazole, but not amphotericin B. Taken together, our findings demonstrate that CBI isolates of Candida have the potential to express to varying extent their virulence attributes (e.g., biofilm formation, hemolysin production, and proteinase activity) and these, together with perturbations in their antifungal sensitivity in the presence of serum, may contribute to treatment complication in candidemia. The effect of serum on antifungal activity

  1. Karyotyping of Candida albicans and Candida glabrata from patients with Candida sepsis.

    PubMed

    Klempp-Selb, B; Rimek, D; Kappe, R

    2000-01-01

    The aim of this study was to determine the relatedness of Candida strains from patients suffering from Candida septicaemia by typing of Candida isolates from blood cultures and different body sites by pulsed field gel electrophoresis (PFGE using a contour-clamped homogenous electric field, CHEF). We studied 17 isolates of Candida albicans and 10 isolates of Candida glabrata from six patients. Four patients suffered from a C. albicans septicaemia, one patient from a C. glabrata septicaemia, and one patient had a mixed septicaemia with C. albicans and C. glabrata. Eight isolates from blood cultures were compared with 19 isolates of other sites (stool six, urine four, genital swab four, tip of central venous catheter three, tracheal secretion one, sputum one). PFGE typing resulted in 10 different patterns, four with C. albicans and six with C. glabrata. Five of the six patients had strains of identical PFGE patterns in the blood and at other sites. Seven isolates of a 58-year-old female with a C. glabrata septicaemia fell into five different PFGE patterns. However, they showed minor differences only, which may be due to chromosomal rearrangements within a single strain. Thus it appears, that the colonizing Candida strains were identical to the circulating strains in the bloodstream in at least five of six patients.

  2. Cilofungin (LY121019), an antifungal agent with specific activity against Candida albicans and Candida tropicalis.

    PubMed Central

    Hall, G S; Myles, C; Pratt, K J; Washington, J A

    1988-01-01

    Cilofungin (LY121019) is an antifungal agent that interferes with beta-glucan synthesis in the cells walls of fungi. The activity of this agent against 256 clinical isolates of yeasts was determined. It was found to be very active in vitro against Candida albicans (MIC for 90% of isolates [MIC90], less than or equal to 0.31 microgram/ml; minimal fungicidal concentration for 90% of isolates [MFC90], less than or equal to 0.31 micrograms/ml) and C. tropicalis (MIC90, less than or equal to 0.31 microgram/ml; MFC90, less than or equal to 0.31 microgram/ml) and moderately active against Torulopsis glabrata (MIC90 and MFC90, less than or equal to 20 micrograms/ml). All C. parapsilosis, Cryptococcus, and Saccharomyces cerevisiae strains were resistant. The activity of cilofungin was affected by medium and inoculum size. Antibiotic medium no. 3 was used as the standard medium. Isolates of C. albicans and C. tropicalis demonstrated a paradoxical effect in Sabouraud dextrose broth and yeast nitrogen base broth in that growth was partially inhibited at MICs equivalent to those in antibiotic medium no. 3, but growth continued, in many instances, throughout all concentrations tested. There was decreased activity of cilofungin with inocula greater than 10(5) CFU/ml. The temperature and duration of incubation did not affect its activity. Images PMID:3058017

  3. Candida milleri species reveals intraspecific genetic and metabolic polymorphisms.

    PubMed

    Vigentini, Ileana; Antoniani, Davide; Roscini, Luca; Comasio, Andrea; Galafassi, Silvia; Picozzi, Claudia; Corte, Laura; Compagno, Concetta; Dal Bello, Fabio; Cardinali, Gianluigi; Foschino, Roberto

    2014-09-01

    Candida milleri, together with Candida humilis, is the most representative yeast species found in type I sourdough ecosystems. In this work, comparison of the ITS region and the D1/D2 domain of 26S rDNA gene partial sequences, karyotyping, mtDNA-RFLP analysis, Intron Splice Site dispersion (ISS-PCR) and (GTG)5 microsatellite analyses, assimilation test of different carbohydrates, and metabolome assessment by FT-IR analysis, were investigated in seventeen strains isolated from four different companies as well as in type strains CBS6897(T) and CBS5658(T). Most isolates were ascribed to C. milleri, even if a strong relatedness was confirmed with C. humilis as well, particularly for three strains. Genetic characterization showed a high degree of intraspecific polymorphism since 12 different genotypes were discriminated. The number of chromosomes varied from 9 to 13 and their size ranged from less than 0.3 to over 2 Mbp. Phenotypic traits let to recognize 9 different profiles of carbon sources assimilation. FT-IR spectra from yeast cells cultivated in different media and collected at different growth phases revealed a diversity of behaviour among strains in accordance with the results of PCR-based fingerprinting. A clear evidence of the polymorphic status of C. milleri species is provided thus representing an important feature for the development of technological applications in bakery industries.

  4. DNA transformations of Candida tropicalis with replicating and integrative vectors.

    PubMed

    Sanglard, D; Fiechter, A

    1992-12-01

    The alkane-assimilating yeast Candida tropicalis was used as a host for DNA transformations. A stable ade2 mutant (Ha900) obtained by UV-mutagenesis was used as a recipient for different vectors carrying selectable markers. A first vector, pMK16, that was developed for the transformation of C. albicans and carries an ADE2 gene marker and a Candida autonomously replicating sequence (CARS) element promoting autonomous replication, was compatible for transforming Ha900. Two transformant types were observed: (i) pink transformants which easily lose pMK16 under non-selective growth conditions; (ii) white transformants, in which the same plasmid exhibited a higher mitotic stability. In both cases pMK16 could be rescued from these cells in Escherichia coli. A second vector, pADE2, containing the isolated C. tropicalis ADE2, gene, was used to transform Ha900. This vector integrated in the yeast genome at homologous sites of the ade2 locus. Different integration types were observed at one or both ade2 alleles in single or in tandem repeats.

  5. DNA transformations of Candida tropicalis with replicating and integrative vectors.

    PubMed

    Sanglard, D; Fiechter, A

    1992-12-01

    The alkane-assimilating yeast Candida tropicalis was used as a host for DNA transformations. A stable ade2 mutant (Ha900) obtained by UV-mutagenesis was used as a recipient for different vectors carrying selectable markers. A first vector, pMK16, that was developed for the transformation of C. albicans and carries an ADE2 gene marker and a Candida autonomously replicating sequence (CARS) element promoting autonomous replication, was compatible for transforming Ha900. Two transformant types were observed: (i) pink transformants which easily lose pMK16 under non-selective growth conditions; (ii) white transformants, in which the same plasmid exhibited a higher mitotic stability. In both cases pMK16 could be rescued from these cells in Escherichia coli. A second vector, pADE2, containing the isolated C. tropicalis ADE2, gene, was used to transform Ha900. This vector integrated in the yeast genome at homologous sites of the ade2 locus. Different integration types were observed at one or both ade2 alleles in single or in tandem repeats. PMID:1293885

  6. Candida milleri species reveals intraspecific genetic and metabolic polymorphisms.

    PubMed

    Vigentini, Ileana; Antoniani, Davide; Roscini, Luca; Comasio, Andrea; Galafassi, Silvia; Picozzi, Claudia; Corte, Laura; Compagno, Concetta; Dal Bello, Fabio; Cardinali, Gianluigi; Foschino, Roberto

    2014-09-01

    Candida milleri, together with Candida humilis, is the most representative yeast species found in type I sourdough ecosystems. In this work, comparison of the ITS region and the D1/D2 domain of 26S rDNA gene partial sequences, karyotyping, mtDNA-RFLP analysis, Intron Splice Site dispersion (ISS-PCR) and (GTG)5 microsatellite analyses, assimilation test of different carbohydrates, and metabolome assessment by FT-IR analysis, were investigated in seventeen strains isolated from four different companies as well as in type strains CBS6897(T) and CBS5658(T). Most isolates were ascribed to C. milleri, even if a strong relatedness was confirmed with C. humilis as well, particularly for three strains. Genetic characterization showed a high degree of intraspecific polymorphism since 12 different genotypes were discriminated. The number of chromosomes varied from 9 to 13 and their size ranged from less than 0.3 to over 2 Mbp. Phenotypic traits let to recognize 9 different profiles of carbon sources assimilation. FT-IR spectra from yeast cells cultivated in different media and collected at different growth phases revealed a diversity of behaviour among strains in accordance with the results of PCR-based fingerprinting. A clear evidence of the polymorphic status of C. milleri species is provided thus representing an important feature for the development of technological applications in bakery industries. PMID:24929720

  7. Eucomic acid methanol monosolvate

    PubMed Central

    Li, Guo-Qiang; Li, Yao-Lan; Wang, Guo-Cai; Liang, Zhi-Hong; Jiang, Ren-Wang

    2011-01-01

    In the crystal structure of the title compound [systematic name: 2-hy­droxy-2-(4-hy­droxy­benz­yl)butane­dioic acid methanol monosolvate], C11H12O6·CH3OH, the dihedral angles between the planes of the carboxyl groups and the benzene ring are 51.23 (9) and 87.97 (9)°. Inter­molecular O—H⋯O hydrogen-bonding inter­actions involving the hy­droxy and carb­oxy­lic acid groups and the methanol solvent mol­ecule give a three-dimensional structure. PMID:22091200

  8. Respiration of medically important Candida species and Saccharomyces cerevisiae in relation to glucose effect.

    PubMed

    Niimi, M; Kamiyama, A; Tokunaga, M

    1988-06-01

    Strains of medically important Candida species (C. albicans, C. tropicalis, C. parapsilosis and C. [Torulopsis] glabrata) and Saccharomyces cerevisiae were examined for a glucose effect on respiratory activity. Reduced O2-consuming ability and a relative decrease in cytochrome type c, as determined by polarography and spectrophotometry, respectively, were observed in glucose-grown S. cerevisiae cells in contrast with acetate- or ethanol-grown cells. In glucose-grown cells of C. glabrata, O2 consumption was also reduced without any change in the cytochrome pattern compared to acetate-grown cells, while no such decrease was detected in any of the other strains of Candida species tested. These results suggest that the medically important Candida species, except for C. glabrata, can be categorized as members of the glucose-insensitive yeast type with respect to respiration.

  9. In vitro phagocytosis of several Candida berkhout species by murine leukocytes.

    PubMed

    Fontenla de Petrino, S E; Bibas Bonet de Jorrat, M E; Sirena, A

    1985-03-01

    In vitro phagocytosis of thirteen Candida berkhout species by rat leukocytes was studied to assess a possible correlation between pathogenicity and phagocytosis Yeast-leukocyte suspensions were mixed up for 3 h and phagocytic index, germ-tube formation and leukocyte candidacidal activity were evaluated. Highest values for phagocytosis were reached in all cases at the end of the first hour. Leukocyte candidacidal activity was absent. Only C. albicans produced germ-tubes. The various phagocytosis indices were determined depending on the Candida species assayed. Under these conditions, the more pathogenic species presented the lower indices of phagocytosis. It is determined that the in vitro phagocytic index may bear a close relationship with the pathogenicity of the Candida berkhout.

  10. Premature delivery due to intrauterine Candida infection that caused neonatal congenital cutaneous candidiasis: a case report.

    PubMed

    Ito, Fumitake; Okubo, Tomoharu; Yasuo, Tadahiro; Mori, Taisuke; Iwasa, Koichi; Iwasaku, Kazuhiro; Kitawaki, Jo

    2013-01-01

    Congenital cutaneous candidiasis is a very rare disease with less than 100 cases published in the medical literature. Neonates having this disease present with systemic skin lesions caused by intrauterine Candida infections. We present a case of threatened premature delivery due to Candida chorioamnionitis, which caused both maternal postpartum endometritis and neonatal congenital cutaneous candidiasis. A 34-year-old woman who was admitted for fetal membrane bulging at 20 weeks of gestation underwent McDonald cervical cerclage. We diagnosed threatened premature delivery due to intrauterine infection; therefore, we terminated the gestation by cesarean section at 24 weeks of gestation. Fungi-like yeast was detected in infantile gastric juice. Histopathological findings of the placenta revealed that Candida albicans mycelium invaded the placenta, chorioamniotic membrane and umbilical cord.

  11. In vitro phagocytosis of several Candida berkhout species by murine leukocytes.

    PubMed

    Fontenla de Petrino, S E; Bibas Bonet de Jorrat, M E; Sirena, A

    1985-03-01

    In vitro phagocytosis of thirteen Candida berkhout species by rat leukocytes was studied to assess a possible correlation between pathogenicity and phagocytosis Yeast-leukocyte suspensions were mixed up for 3 h and phagocytic index, germ-tube formation and leukocyte candidacidal activity were evaluated. Highest values for phagocytosis were reached in all cases at the end of the first hour. Leukocyte candidacidal activity was absent. Only C. albicans produced germ-tubes. The various phagocytosis indices were determined depending on the Candida species assayed. Under these conditions, the more pathogenic species presented the lower indices of phagocytosis. It is determined that the in vitro phagocytic index may bear a close relationship with the pathogenicity of the Candida berkhout. PMID:3990766

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

    PubMed

    Ciafardini, G; Zullo, B A

    2015-05-01

    Previous microbiological research demonstrated the presence of a rich micro-flora composed mainly of yeasts in the suspended fraction of freshly produced olive oil. Some of the yeasts are considered harmful as they can damage the quality of the olive oil through the hydrolysis of the triacylglycerols. Present research has demonstrated that the lipolytic activity of some lipase-producer strains belonging to a yeast species called Candida adriatica, Candida diddensiae and Yamadazyma terventina can be modulated by the water and the polyphenol content of olive oil. Laboratory tests highlighted a substantial increase in free fatty acid in the inoculated olive oil characterized by high water content and low polyphenol concentration. The acidity of the olive oil samples containing 0.06% and 0.31% of water increased significantly by 33% in the lipase-producer yeast strains tested during a period of 2 weeks of incubation at 30 °C. All other yeasts showed strong lipolytic activity in the presence of 1.31% of water - the only exception to this was the C. adriatica 1985 strain. The phenolic compounds typical of olive oil represent another important factor able to condition the viability and the lipolytic activity of the lipase-producer yeasts. From the tests performed on the olive oil characterized by an increasing content of total polyphenols equal to 84, 150 and 510 mg per kg of oil, the percentage of the lipase-producer yeasts able to hydrolyse the triacylglycerols was respectively 100%, 67% and 11%. PMID:25583333

  13. The dynamics of the yeast community of the Tagus river estuary: testing the hypothesis of the multiple origins of estuarine yeasts.

    PubMed

    Coelho, Marco A; Almeida, João M F; Martins, Inês M; da Silva, A Jorge; Sampaio, José Paulo

    2010-10-01

    Yeasts are common inhabitants of different types of aquatic habitats, including marine and estuarine waters and rivers. Although numerous studies have surveyed yeast occurrence in these habitats, the identification of autochthonous populations has been problematic because several yeast species seem to be very versatile and therefore mere presence is not sufficient to establish an ecological association. In the present study we investigated the dynamics of the yeast community in the Tagus river estuary (Portugal) by combining a microbiological study involving isolation, quantification, and molecular identification of dominant yeast populations with the analysis of hydrological and hydrographical data. We set out to test the hypothesis of the multiple origins of estuarine yeast populations in a transect of the Tagus estuary and we postulate four possible sources: open sea, terrestrial, gastrointestinal and the estuary itself in the case of populations that have become resident. Candida parapsilosis and Pichia guilliermondii were correlated with Escherichia coli, which indicated an intestinal origin. Other cream-colored yeasts like Debaryomyces hansenii and Candida zeylanoides had similar dynamics, but no association with E. coli and quite distinct ecological preferences. They might represent a group of resident estuarine populations whose primary origin is diverse and can include marine, terrestrial, and gastrointestinal habitats. Another major yeast population was represented by Rhodotorula mucilaginosa. The cosmopolitan nature of that species and its moderate association with E. coli point to terrestrial sources as primary habitats. PMID:20422287

  14. The dynamics of the yeast community of the Tagus river estuary: testing the hypothesis of the multiple origins of estuarine yeasts.

    PubMed

    Coelho, Marco A; Almeida, João M F; Martins, Inês M; da Silva, A Jorge; Sampaio, José Paulo

    2010-10-01

    Yeasts are common inhabitants of different types of aquatic habitats, including marine and estuarine waters and rivers. Although numerous studies have surveyed yeast occurrence in these habitats, the identification of autochthonous populations has been problematic because several yeast species seem to be very versatile and therefore mere presence is not sufficient to establish an ecological association. In the present study we investigated the dynamics of the yeast community in the Tagus river estuary (Portugal) by combining a microbiological study involving isolation, quantification, and molecular identification of dominant yeast populations with the analysis of hydrological and hydrographical data. We set out to test the hypothesis of the multiple origins of estuarine yeast populations in a transect of the Tagus estuary and we postulate four possible sources: open sea, terrestrial, gastrointestinal and the estuary itself in the case of populations that have become resident. Candida parapsilosis and Pichia guilliermondii were correlated with Escherichia coli, which indicated an intestinal origin. Other cream-colored yeasts like Debaryomyces hansenii and Candida zeylanoides had similar dynamics, but no association with E. coli and quite distinct ecological preferences. They might represent a group of resident estuarine populations whose primary origin is diverse and can include marine, terrestrial, and gastrointestinal habitats. Another major yeast population was represented by Rhodotorula mucilaginosa. The cosmopolitan nature of that species and its moderate association with E. coli point to terrestrial sources as primary habitats.

  15. Synergistic effect of amphotericin B and tyrosol on biofilm formed by Candida krusei and Candida tropicalis from intrauterine device users.

    PubMed

    Shanmughapriya, Santhanam; Sornakumari, Haridevvenkatesan; Lency, Arumugam; Kavitha, Senthil; Natarajaseenivasan, Kalimuthusamy

    2014-11-01

    The presence of intrauterine contraceptive devices (IUDs) provides a solid surface for attachment of microorganisms and an ideal niche for the biofilm to form and flourish. Vaginal candidiasis is often associated with the use of IUDs. Treatment of vaginal candidiasis that develops in connection with IUD use requires their immediate removal. Here, we present in vitro evidence to support the use of combination therapy to inhibit Candida biofilm. Twenty-three clinical Candida isolates (10 C. krusei and 13 C. tropicalis) recovered from endocervical swabs obtained from IUD and non-IUD users were assessed for biofilm-formation ability. The rate of isolation of Candida did not differ significantly among IUD and non-IUD users (P = 0.183), but the biofilm-formation ability of isolates differed significantly (P = 0.02). An in vitro biofilm model with the obtained isolates was subjected to treatment with amphotericin B, tyrosol, and a combination of amphotericin B and tyrosol. Inhibition of biofilm by amphotericin B or tyrosol was found to be concentration dependent, with 50% reduction (P < 0.05) at 4 mg/l and 80 μM, respectively. Hence, a combination effect of tyrosol and amphotericin B was studied. Interestingly, approximately 90% reduction in biofilm was observed with use of 80 μM tyrosol combined with 4 mg/l amphotericin B (P < 0.001). This represents a first step in establishing an appropriate antibiofilm therapy when yeasts are present.

  16. Methanol in dark clouds.

    PubMed

    Friberg, P; Madden, S C; Hjalmarson, A; Irvine, W M

    1988-01-01

    We report observations, for the first time, of the 2(0) - 1(0)A+ and E, 2(-1) - 1(-1) E, and 1(0) - 0(0)A+ lines of methanol (CH3OH) in three dark cold clouds, TMC1, L134N, and B335. The CH3OH emission is extended in these clouds and shows a complex velocity structure. Clear indications of non LTE excitation are observed in TMC 1. Estimated column densities are a few 10(13) cm-2. Although less abundant than formaldehyde (H2CO), methanol is almost an order of magnitude more abundant than acetaldehyde (CH3CHO), in these clouds. Dimethyl ether was searched for in L134N, to an upper limit of 4 10(12) cm-2 (3 sigma). Implications for dark cloud excitation and chemistry are discussed. A new, more accurate, rest frequency 96741.39(0.01) MHz is determined for the 2(0) - 1(0) A+ E line of methanol.

  17. The toxicity of methanol

    SciTech Connect

    Tephly, T.R. )

    1991-01-01

    Methanol toxicity in humans and monkeys is characterized by a latent period of many hours followed by a metabolic acidosis and ocular toxicity. This is not observed in most lower animals. The metabolic acidosis and blindness is apparently due to formic acid accumulation in humans and monkeys, a feature not seen in lower animals. The accumulation of formate is due to a deficiency in formate metabolism which is, in turn, related, in part, to low hepatic tetrahydrofolate (H{sub 4}folate). An excellent correlation between hepatic H{sub 4} folate and formate oxidation rates has been shown within and across species. Thus, humans and monkeys possess low hepatic H{sub 4}folate levels, low rates of formate oxidation and accumulation of formate after methanol. Formate, itself, produces blindness in monkeys in the absence of metabolic acidosis. In addition to low hepatic H{sub 4}folate concentrations, monkeys and humans also have low hepatic 10-formyl H{sub 4}folate dehydrogenase levels, the enzyme which is the ultimate catalyst for conversion of formate to carbon dioxide. This review presents the basis for the role of folic acid-dependent reactions in the regulation of methanol toxicity.

  18. California methanol assessment. Volume 2: Technical report

    NASA Technical Reports Server (NTRS)

    Otoole, R.; Dutzi, E.; Gershman, R.; Heft, R.; Kalema, W.; Maynard, D.

    1983-01-01

    Energy feedstock sources for methanol; methanol and other synfuels; transport, storage, and distribution; air quality impact of methanol use in vehicles, chemical methanol production and use; methanol utilization in vehicles; methanol utilization in stationary applications; and environmental and regulatory constraints are discussed.

  19. Multivariate analysis to discriminate yeast strains with technological applications in table olive processing.

    PubMed

    Rodríguez-Gómez, Francisco; Romero-Gil, Veronica; Bautista-Gallego, Joaquín; Garrido-Fernández, Antonio; Arroyo-López, Francisco Noé

    2012-04-01

    This survey uses a multivariate classification analysis to discriminate yeast strains with interesting biochemical activities for the processing of table olives among a collection of 32 isolates belonging to 16 different yeast species. Lipase, esterase and β-glucosidase activities (desirable characteristics) were quantitatively evaluated in both extracellular and cellular fractions for all isolates in different types of culture media. The study of the quantitative data by cluster and principal component analyses led to the identification of several Wickerhamomyces anomalus, Candida boidinii and Candida diddensiae isolates with promising characteristics (the best global activity levels), clearly differentiated from the rest of the yeasts. The results obtained in this work open up new alternatives to this methodology for the study, classification and selection of the most suitable yeasts to be used as starters, alone or in combination with lactic acid bacteria, during table olive processing.

  20. Yeast identification in floral nectar of Mimulus aurantiacus (Invited)

    NASA Astrophysics Data System (ADS)

    Kyauk, C.; Belisle, M.; Fukami, T.

    2009-12-01

    Nectar is such a sugar-rich resource that serves as a natural habitat in which microbes thrive. As a result, yeasts arrive to nectar on the bodies of pollinators such as hummingbirds and bees. Yeasts use the sugar in nectar for their own needs when introduced. This research focuses on the identification of different types of yeast that are found in the nectar of Mimulus aurantiacus (commonly known as sticky monkey-flower). Unopened Mimulus aurantiacus flower buds were tagged at Jasper Ridge and bagged three days later. Floral nectar was then extracted and plated on potato dextrose agar. Colonies on the plates were isolated and DNA was extracted from each sample using QIAGEN DNeasy Plant Mini Kit. The DNA was amplified through PCR and ran through gel electrophoresis. The PCR product was used to clone the nectar samples into an E.coli vector. Finally, a phylogenetic tree was created by BLAST searching sequences in GenBank using the Internal Transcribed Space (ITS) locus. It was found that 18 of the 50 identified species were Candida magnifica, 14 was Candida rancensis, 6 were Crytococcus albidus and there were 3 or less of the following: Starmella bombicola, Candida floricola, Aureobasidium pullulans, Pichia kluyvera, Metschnikowa cibodaserisis, Rhodotorua colostri, and Malassezia globosa. The low diversity of the yeast could have been due to several factors: time of collection, demographics of Jasper Ridge, low variety of pollinators, and sugar concentration of the nectar. The results of this study serve as a necessary first step for a recently started research project on ecological interactions between plants, pollinators, and nectar-living yeast. More generally, this research studies the use of the nectar-living yeast community as a natural microcosm for addressing basic questions about the role of dispersal and competitive and facilitative interactions in ecological succession.

  1. Whole genome sequencing of emerging multidrug resistant Candida auris isolates in India demonstrates low genetic variation.

    PubMed

    Sharma, C; Kumar, N; Pandey, R; Meis, J F; Chowdhary, A

    2016-09-01

    Candida auris is an emerging multidrug resistant yeast that causes nosocomial fungaemia and deep-seated infections. Notably, the emergence of this yeast is alarming as it exhibits resistance to azoles, amphotericin B and caspofungin, which may lead to clinical failure in patients. The multigene phylogeny and amplified fragment length polymorphism typing methods report the C. auris population as clonal. Here, using whole genome sequencing analysis, we decipher for the first time that C. auris strains from four Indian hospitals were highly related, suggesting clonal transmission. Further, all C. auris isolates originated from cases of fungaemia and were resistant to fluconazole (MIC >64 mg/L).

  2. The role of pattern recognition receptors in the innate recognition of Candida albicans.

    PubMed

    Zheng, Nan-Xin; Wang, Yan; Hu, Dan-Dan; Yan, Lan; Jiang, Yuan-Ying

    2015-01-01

    Candida albicans is both a commensal microorganism in healthy individuals and a major fungal pathogen causing high mortality in immunocompromised patients. Yeast-hypha morphological transition is a well known virulence trait of C. albicans. Host innate immunity to C. albicans critically requires pattern recognition receptors (PRRs). In this review, we summarize the PRRs involved in the recognition of C. albicans in epithelial cells, endothelial cells, and phagocytic cells separately. We figure out the differential recognition of yeasts and hyphae, the findings on PRR-deficient mice, and the discoveries on human PRR-related single nucleotide polymorphisms (SNPs).

  3. Antimicrobial activity of nisin, thymol, carvacrol and cymene against growth of Candida lusitaniae.

    PubMed

    Aznar, Arantxa; Fernández, Pablo S; Periago, Paula M; Palop, Alfredo

    2015-01-01

    Yeasts are tolerant to acid pH values, are able to grow in anaerobic media and have minimum nutrition requirements. These capabilities enable them to survive and even grow in foods prepared from acid fruits or vegetables. Among yeasts, Candida is one of the genus most frequently isolated from fruit juices. Bacteriocins and essential oils from spices and aromatic herbs are an alternative to preservatives and other technological treatments and have the advantage that their natural origins do not lead to consumer rejection. However, before the food industry uses them on a large scale, it is necessary to know their effects on microorganisms. The objective of this research was to study the effect of different concentrations of nisin, thymol, carvacrol and cymene on the growth of Candida lusitaniae in pH 5 broth at 25 ℃, and their potential uses as food preservatives. The addition of nisin at the concentrations tested (up to 3 µmol L(-1)) did not affect the yeast growth. Thymol, carvacrol and cymene completely inhibited the yeast growth at concentrations over 1 mM for at least 21 days at 25 ℃. Below this concentration, inhibitions on yeast growth were observed at increasing concentrations. The effect of thymol was also proved in tomato juice. This study indicates the potential use of essential oils for preservation of minimally processed foods.

  4. Characterization of thiamine uptake and utilization in Candida spp. subjected to oxidative stress.

    PubMed

    Wolak, Natalia; Tomasi, Massimo; Kozik, Andrzej; Rapala-Kozik, Maria

    2015-01-01

    Candida species are associated with an increasing number of life-threatening infections (candidiases), mainly due to the high resistance of these yeast-like fungi to antifungal drugs and oxidative stress. Recently, thiamine (vitamin B1) was found to alleviate stress responses in Saccharomyces cerevisiae; however, thiamine influence on defense systems in pathogenic fungi has never been investigated. The current work was aimed to elucidate the role of thiamine in stress reactions of C. albicans, C. glabrata, C. tropicalis and C. dubliniensis, subjected to hydrogen peroxide treatment. As compared to S. cerevisiae, Candida strains exposed to oxidative stress showed: (i) a much higher dependence on exogenous thiamine; (ii) an increased demand for thiamine diphosphate (TDP) and TDP-dependent enzyme, transketolase; (iii) no changes in gene expression of selected stress markers - superoxide dismutase and catalase - depending on thiamine availability in medium; (iv) a similar decrease of reactive oxygen species (ROS) generation in the presence of thiamine. Moreover, the addition of therapeutic doses of thiamine to yeast culture medium revealed differences in its accumulation between various Candida species. The current findings implicate that the protective action of thiamine observed in S. cerevisiae differs significantly form that in pathogenic Candida strains, both in terms of the cofactor functions of TDP and the effects on fungal defense systems. PMID:26284264

  5. Application of MALDI-TOF MS for requalification of a Candida clinical isolates culture collection

    PubMed Central

    Lima-Neto, Reginaldo; Santos, Cledir; Lima, Nelson; Sampaio, Paula; Pais, Célia; Neves, Rejane P.

    2014-01-01

    Microbial culture collections underpin biotechnology applications and are important resources for clinical microbiology by supplying reference strains and/or performing microbial identifications as a service. Proteomic profiles by MALDI-TOF MS have been used for Candida spp. identification in clinical laboratories and demonstrated to be a fast and reliable technique for the routine identification of pathogenic yeasts. The main aim of this study was to apply MALDI-TOF MS combined with classical phenotypic and molecular approaches to identify Candida clinical isolates preserved from 1 up to 52 years in a Brazilian culture collection and assess its value for the identification of yeasts preserved in this type of collections. Forty Candida spp. clinical isolates were identified by morphological and biochemical analyses. Identifications were also performed by the new proteomic approach based on MALDI-TOF MS. Results demonstrated 15% discordance when compared with morphological and biochemical analyses. Discordant isolates were analysed by ITS sequencing, which confirmed the MALDI-TOF MS identifications and these strains were renamed in the culture collection catalogue. In conclusion, proteomic profiles by MALDI-TOF MS represents a rapid and reliable method for identifying clinical Candida species preserved in culture collections and may present clear benefits when compared with the performance of existing daily routine methods applied at health centres and hospitals. PMID:25242936

  6. Characterization of thiamine uptake and utilization in Candida spp. subjected to oxidative stress.

    PubMed

    Wolak, Natalia; Tomasi, Massimo; Kozik, Andrzej; Rapala-Kozik, Maria

    2015-01-01

    Candida species are associated with an increasing number of life-threatening infections (candidiases), mainly due to the high resistance of these yeast-like fungi to antifungal drugs and oxidative stress. Recently, thiamine (vitamin B1) was found to alleviate stress responses in Saccharomyces cerevisiae; however, thiamine influence on defense systems in pathogenic fungi has never been investigated. The current work was aimed to elucidate the role of thiamine in stress reactions of C. albicans, C. glabrata, C. tropicalis and C. dubliniensis, subjected to hydrogen peroxide treatment. As compared to S. cerevisiae, Candida strains exposed to oxidative stress showed: (i) a much higher dependence on exogenous thiamine; (ii) an increased demand for thiamine diphosphate (TDP) and TDP-dependent enzyme, transketolase; (iii) no changes in gene expression of selected stress markers - superoxide dismutase and catalase - depending on thiamine availability in medium; (iv) a similar decrease of reactive oxygen species (ROS) generation in the presence of thiamine. Moreover, the addition of therapeutic doses of thiamine to yeast culture medium revealed differences in its accumulation between various Candida species. The current findings implicate that the protective action of thiamine observed in S. cerevisiae differs significantly form that in pathogenic Candida strains, both in terms of the cofactor functions of TDP and the effects on fungal defense systems.

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

    PubMed

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

    2014-04-01

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

  8. Impaired killing of Candida albicans by granulocytes mobilized for transfusion purposes: a role for granule components

    PubMed Central

    Gazendam, Roel P.; van de Geer, Annemarie; van Hamme, John L.; Tool, Anton T.J.; van Rees, Dieke J.; Aarts, Cathelijn E.M.; van den Biggelaar, Maartje; van Alphen, Floris; Verkuijlen, Paul; Meijer, Alexander B.; Janssen, Hans; Roos, Dirk; van den Berg, Timo K.; Kuijpers, Taco W.

    2016-01-01

    Granulocyte transfusions are used to treat neutropenic patients with life-threatening bacterial or fungal infections that do not respond to anti-microbial drugs. Donor neutrophils that have been mobilized with granulocyte-colony stimulating factor (G-CSF) and dexamethasone are functional in terms of antibacterial activity, but less is known about their fungal killing capacity. We investigated the neutrophil-mediated cytotoxic response against C. albicans and A. fumigatus in detail. Whereas G-CSF/dexamethasone-mobilized neutrophils appeared less mature as compared to neutrophils from untreated controls, these cells exhibited normal ROS production by the NADPH oxidase system and an unaltered granule mobilization capacity upon stimulation. G-CSF/dexamethasone-mobilized neutrophils efficiently inhibited A. fumigatus germination and killed Aspergillus and Candida hyphae, but the killing of C. albicans yeasts was distinctly impaired. Following normal Candida phagocytosis, analysis by mass spectrometry of purified phagosomes after fusion with granules demonstrated that major constituents of the antimicrobial granule components, including major basic protein (MBP), were reduced. Purified MBP showed candidacidal activity, and neutrophil-like Crisp-Cas9 NB4-KO-MBP differentiated into phagocytes were impaired in Candida killing. Together, these findings indicate that G-CSF/dexamethasone-mobilized neutrophils for transfusion purposes have a selectively impaired capacity to kill Candida yeasts, as a consequence of an altered neutrophil granular content. PMID:26802050

  9. Impaired killing of Candida albicans by granulocytes mobilized for transfusion purposes: a role for granule components.

    PubMed

    Gazendam, Roel P; van de Geer, Annemarie; van Hamme, John L; Tool, Anton T J; van Rees, Dieke J; Aarts, Cathelijn E M; van den Biggelaar, Maartje; van Alphen, Floris; Verkuijlen, Paul; Meijer, Alexander B; Janssen, Hans; Roos, Dirk; van den Berg, Timo K; Kuijpers, Taco W

    2016-05-01

    Granulocyte transfusions are used to treat neutropenic patients with life-threatening bacterial or fungal infections that do not respond to anti-microbial drugs. Donor neutrophils that have been mobilized with granulocyte-colony stimulating factor (G-CSF) and dexamethasone are functional in terms of antibacterial activity, but less is known about their fungal killing capacity. We investigated the neutrophil-mediated cytotoxic response against C. albicans and A. fumigatus in detail. Whereas G-CSF/dexamethasone-mobilized neutrophils appeared less mature as compared to neutrophils from untreated controls, these cells exhibited normal ROS production by the NADPH oxidase system and an unaltered granule mobilization capacity upon stimulation. G-CSF/dexamethasone-mobilized neutrophils efficiently inhibited A. fumigatus germination and killed Aspergillus and Candida hyphae, but the killing of C. albicans yeasts was distinctly impaired. Following normal Candida phagocytosis, analysis by mass spectrometry of purified phagosomes after fusion with granules demonstrated that major constituents of the antimicrobial granule components, including major basic protein (MBP), were reduced. Purified MBP showed candidacidal activity, and neutrophil-like Crisp-Cas9 NB4-KO-MBP differentiated into phagocytes were impaired in Candida killing. Together, these findings indicate that G-CSF/dexamethasone-mobilized neutrophils for transfusion purposes have a selectively impaired capacity to kill Candida yeasts, as a consequence of an altered neutrophil granular content. PMID:26802050

  10. Fermentation of xylulose to ethanol using xylose isomerase and yeasts

    SciTech Connect

    Jeffries, T.W.

    1981-01-01

    In a survey of 35 organisms, predominantly yeasts, about 40% were capable of fermenting xylulose to ethanol. Two species, Candida tropicalis and Schizosaccharomyces pombe, did so at good rates and without an initial lag. Saccharomyces cerevisiae strains that fermented glucose rapidly fermented xylulose at a slower rate. Ten yeasts and three strains of the bacterium Zymomonas mobilis were weak or negative for xylulose, even though they fermented glucose under the conditions employed. C. tropicalis was able to form 1.0 M ethanol from 1.0 M xylose if the fermentation broth was recycled over immobilized xylose isomerase.

  11. Identification of yeasts from clinical specimens by oxidase test.

    PubMed

    Kumar, S; Arora, B S; Mathur, M D

    2000-10-01

    A total of 100 yeasts and yeast like fungi isolates from clinical specimens were negative for oxidase production on Sabouraud dextrose agar. When grown on Columbia agar, chocolate agar, tryptose agar, Mueller-Hinton agar, brain heart infusion and a medium resembling Sabouraud's dextrose agar but with starch instead of dextrose, all the isolate of Candida albicans (55), C. guilliermondii (6), C. parapsilosis (14), C. tropicalis (6), C. pseudotropicalis (6) and Crytococcus neoformans (2) were positive for oxidase producation. Torulopsis glabrata (2), Saccharomyces cervisiae (2) and two out of seven isolates of C. krusei were negative for oxidase test. PMID:11344606

  12. Candida albicans blastoconidia in peripheral blood smears from non-neutropenic surgical patients.

    PubMed

    Berrouane, Y; Bisiau, H; Le Baron, F; Cattoen, C; Duthilleul, P; Dei Cas, E

    1998-07-01

    An 80 year old woman developed fever 11 days after volvulus surgery. A peripheral blood smear showed numerous yeast cells--both extraleucocytic and intraleucocytic--as well as leucoagglutination. The fungal elements included blastospores, pseudohyphae, and germ tubes. Two days later, blood cultures yielded Candida albicans, Enterobacter aerogenes, and Staphlococcus aureus. The patient had no medical history of immunodeficiency. Several reports indicate that fungal elements may be detected in peripheral blood smears from patients who have a severe intestinal disease.

  13. New aniline blue dye medium for rapid identification and isolation of Candida albicans.

    PubMed Central

    Goldschmidt, M C; Fung, D Y; Grant, R; White, J; Brown, T

    1991-01-01

    Organic dyes have long been used in diagnostic microbiology to differentiate species by color reactions. We studied the ability of a new noninhibitory medium, YM agar containing 0.01% aniline blue WS dye, Colour Index 42780 (YMAB), to identify Candida albicans among 1,554 yeast specimens obtained from seven clinical laboratories. Appropriate American Type Culture Collection and other characterized strains served as controls. A total of 487 of the clinical strains were identified as C. albicans. The remainder were other Candida species and non-Candida yeasts. Clinical isolates and controls were grown on Sabouraud agar for 18 h at 30 degrees C and then transferred to YMAB. Plates were incubated for 12 to 18 h at 30 degrees C, and colonies were observed for yellow-green fluorescence under long-wave UV light (A365). All control strains of C. albicans and Candida stellatoidea fluoresced, as did 480 of the 490 isolates designated as C. albicans (which included 3 strains of C. stellatoidea). Cells of C. albicans grown on YMAB produced germ tubes in serum. Only five of the other 1,062 non-C. albicans yeasts fluoresced. The sensitivity and specificity were 98.0 and 99.5%, respectively, with a predictive value of 99.1%. A fluorescent metabolite was found in cell wall particulate fractions of C. albicans sonic extracts grown on YMAB but not in non-C. albicans yeasts. This metabolite showed the same spectral curve as those of metabolites from whole cells in a recording spectrofluorometer when it was excited at 400 nm and scanned from 420 to 550 nm. Thus, growth on YMAB generates the production of a fluorescent moiety that can be used to specifically identify C. albicans within 12 to 18 h. Images PMID:1864924

  14. [Riboflavin transport in cells of riboflavin-dependent yeast mutants].

    PubMed

    Sibirnyĭ, A A; Shavlovskiĭ, G M; Ksheminskaia, G P; Orlovskaia, A G

    1977-01-01

    Riboflavin was transported at a high rate into yeast cells of Pichia guilliermondii and Schwanniomyces occidentalis mutants capable of growth in a medium containing low concentrations of riboflavin, and having multiple susceptibility to some antibiotics and antimetabolites. Sucrose and sodium azide inhibited transport of riboflavin. Other riboflavin dependent mutants of Pichia guilliermondii, Pichia ohmeri, Torulopsis candida, and Saccharomyces cerevisiae, also growing in media containing low concentrations of riboflavin, were not capable of its active transport. PMID:329070

  15. A Glucose Sensor in Candida albicans†

    PubMed Central

    Brown, Victoria; Sexton, Jessica A.; Johnston, Mark

    2006-01-01

    The Hgt4 protein of Candida albicans (orf19.5962) is orthologous to the Snf3 and Rgt2 glucose sensors of Saccharomyces cerevisiae that govern sugar acquisition by regulating the expression of genes encoding hexose transporters. We found that HGT4 is required for glucose induction of the expression of HGT12, HXT10, and HGT7, which encode apparent hexose transporters in C. albicans. An hgt4Δ mutant is defective for growth on fermentable sugars, which is consistent with the idea that Hgt4 is a sensor of glucose and similar sugars. Hgt4 appears to be sensitive to glucose levels similar to those in human serum (∼5 mM). HGT4 expression is repressed by high levels of glucose, which is consistent with the idea that it encodes a high-affinity sugar sensor. Glucose sensing through Hgt4 affects the yeast-to-hyphal morphological switch of C. albicans cells: hgt4Δ mutants are hypofilamented, and a constitutively signaling form of Hgt4 confers hyperfilamentation of cells. The hgt4Δ mutant is less virulent than wild-type cells in a mouse model of disseminated candidiasis. These results suggest that Hgt4 is a high-affinity glucose sensor that contributes to the virulence of C. albicans. PMID:17030998

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

    PubMed

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

    2007-10-01

    The yeast pathogen Candida glabrata is a nicotinamide adenine dinucleotide (NAD(+)) auxotroph and its growth depends on the environmental supply of vitamin precursors of NAD(+). C. glabrata salvage pathways defined in this article allow NAD(+) to be synthesized from three compounds - nicotinic acid (NA), nicotinamide (NAM) and nicotinamide riboside (NR). NA is salvaged through a functional Preiss-Handler pathway. NAM is first converted to NA by nicotinamidase and then salvaged by the Preiss-Handler pathway. Salvage of NR in C. glabrata occurs via two routes. The first, in which NR is phosphorylated by the NR kinase Nrk1, is independent of the Preiss-Handler pathway. The second is a novel pathway in which NR is degraded by the nucleosidases Pnp1 and Urh1, with a minor role for Meu1, and ultimately converted to NAD(+) via the nicotinamidase Pnc1 and the Preiss-Handler pathway. Using C. glabrata mutants whose growth depends exclusively on the external NA or NR supply, we also show that C. glabrata utilizes NR and to a lesser extent NA as NAD(+) sources during disseminated infection. PMID:17725566

  17. 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

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

    PubMed

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

    2006-11-01

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

  19. Anti-Candida and anti-Cryptococcus antifungal produced by marine microorganisms.

    PubMed

    El Amraoui, B; El Amraoui, M; Cohen, N; Fassouane, A

    2014-12-01

    In order to search for antifungal from biological origin, we performed a screening of marine microorganisms isolated from seawater, seaweed, sediment and marine invertebrates collected from different coastal areas of the Moroccan Atlantic Ocean. The antifungal activities of these isolates were investigated against the pathogenic yeasts involved in medical mycology. Whole cultures of 34 marine microorganisms were screened for antifungal activities using the method of agar diffusion against four yeasts. The results showed that among the 34 isolates studied, 13 (38%) strains have antifungal activity against at least one out of four yeast species, 11 isolates have anti-Candida albicans CIP 48.72 activity, 12 isolates have anti-C. albicans CIP 884.65 activity, 13 isolates have anti-Cryptococcus neoformans activity and only 6 isolates are actives against Candida tropicalis R2 resistant to nystatin and amphotericin B. Nine isolates showed strong fungicidal activity. Fourteen microorganisms were identified and assigned to the genera Acinetobacter, Aeromonas, Alcaligenes, Bacillus, Chromobacterium, Enterococcus, Pantoea, and Pseudomonas. Due to a competitive role for space and nutrient, the marine microorganisms could produce more antimicrobials; therefore these marine microorganisms were expected to be potential resources of natural products such as those we research: anti-Candida and anti-Cryptococcus fungicides.

  20. Prevalence of Candida dubliniensis among cancer patients in Kuwait: a 5-year retrospective study.

    PubMed

    Mokaddas, Eiman; Khan, Zia U; Ahmad, Suhail

    2011-07-01

    Despite close genetic and phenotypic relationship of Candida dubliniensis with Candida albicans, its role in human disease is mostly restricted to oral colonisation, particularly among HIV-infected patients. The prevalence of C. dubliniensis in association with other disease conditions has been infrequently reported. In this study, we present data on the prevalence of C. dubliniensis among yeast species isolated from cancer patients over a 5-year period. A total of 1445 yeast isolates recovered from respiratory specimens, blood, urine and oral swabs were analysed. Candida dubliniensis isolates were provisionally identified by phenotypic methods and their identity was further confirmed by species-specific amplification and/or sequencing of internally transcribed spacer region of rDNA. Antifungal susceptibility for fluconazole was determined by Etest. The number of isolates identified as C. dubliniensis, C. albicans and other yeast species were 71 (4.9%), 862 (59.6%) and 512 (35%) respectively. All the C. dubliniensis isolates originated from respiratory (5.9%) or oral (3.2%) specimens with an overall prevalence of 4.9%, and were found to be susceptible to fluconazole. The isolation of C. dubliniensis from respiratory or oral specimens and not from blood or urine specimens suggests that this species has preference to colonise these sites of human body.

  1. Investigating of yeast species in wine fermentation using terminal restriction fragment length polymorphism method.

    PubMed

    Sun, Yue; Liu, Yanlin

    2014-04-01

    The objective of this study was to examine the potential of terminal restriction fragment length polymorphism (T-RFLP) in monitoring yeast communities during wine fermentation and to reveal new information on yeast community of Chinese enology. Firstly, terminal restriction fragment (TRF) lengths database was constructed using 32 pure yeast species. Ten of these species were firstly documented. The species except for Candida vini, Issatchenkia orientalis/Candida krusei, Saccharomyces bayanus, Saccharomyces pastorianus, Saccharomyces cerevisiae, Saccharomyces kudriarzevii and Zygosaccharomyces bisporus could be distinguished by the T-RFLP targeting 5.8S-ITS rDNA. Moreover, the yeast communities in spontaneous fermentation of Chardonnay and Riesling were identified by T-RFLP and traditional methods, including colony morphology on Wallerstein Nutrient (WLN) medium and 5.8S-ITS-RFLP analysis. The result showed that T-RFLP profiles of the yeast community correlated well with that of the results identified by the traditional methods. The TRFs with the highest intensity and present in all the samples corresponded to Saccharomyces sp. Other species detected by both approaches were Hanseniaspora uvarum, Metschnikowia pulcherrima, Pichia minuta var. minuta, Saccharomycodes ludwigii/Torulaspora delbrueckii and Candida zemplinina. This study revealed that T-RFLP technique is a rapid and useful tool for monitoring the composition of yeast species during wine fermentation.

  2. [Activities of some yeast flavogenic enzymes in situ].

    PubMed

    Logvinenko, E M; Trach, V M; Kashchenko, V E; Zakal'skiĭ, A E; Koltun, L V; Shavlovskiĭ, G M

    1977-09-01

    Effects of digitonin, dimethylsulfoxide and protamine sulfate on yeast Pichia guilliermondii were studied in order to produce cells with increased permeability and possessing the GTP-cyclohydrolase, riboflavinsynthetase and riboflavinkinase activities. The digitonin-treated cells exhibited a higher cyclohydrolase activity than the cell-free extracts; the activities of riboflavinsynthetase and riboflavinkinase in the cells and cell-free extracts were found to be similar. Treatment of cells with dimethylsulfoxide proved to be most effective to determine the activity of GTP-cyclohydrolase and also helpful to determine that of riboflavinsynthetase. Protamine sulfate had no effect on the cells of P. guilliermondii. The methods developed were used to determine the activities of GTP-cyclohydrolase, riboflavinsynthetase and riboflavinkinase in the cells of flavinogenic (P. guiller-mondii, Torulopsis candida) and non-flavinogenic (Candida utilis, Candida pulcherrima) yeasts grown in iron-rich and iron-deficient media. Derepression of riboflavinsynthetase and GTP-cyclohydrolase syntheses under conditions of Fe deficiency in the flavinogenic yeast cells confirmed previously made assumptions. PMID:199288

  3. Growth and Pigment Production on d-Tryptophan Medium by Cryptococcus gattii, Cryptococcus neoformans, and Candida albicans▿

    PubMed Central

    Chaskes, Stuart; Frases, Susana; Cammer, Michael; Gerfen, Gary; Casadevall, Arturo

    2008-01-01

    Given the increasing prevalence of cryptococcosis caused by Cryptococcus gattii (serotypes B and C) strains, there is a need for rapid and reliable tests that discriminate C. gattii from Cryptococcus neoformans (serotypes A, D, and AD). Seventy-two C. neoformans strains, sixty-seven C. gattii strains, and five Candida albicans strains were analyzed for their ability to grow and produce pigment on minimal d-tryptophan d-proline (m-DTDP) medium, on yeast carbon base d-tryptophan d-proline (YCB-DTDP) medium, and on fructose d-tryptophan glycine (m-FDTG) medium. Of the C. gattii and C. neoformans isolates, 94% and 0% grew on m-DTDP agar, respectively, and 98% and 0% grew in YCB-DTDP medium, respectively. C. gattii produced large amounts of brown intracellular pigment(s) on m-DTDP agar and smaller amounts of yellow-brown (amber) extracellular pigment(s). C. albicans grew on both media and produced a pink photoactivated pigment on m-DTDP agar. C. gattii produced large amounts of brown intracellular pigments on the differential medium m-FDTG, whereas C. neoformans produced smaller amounts of the brown pigments and C. albicans produced a pink pigment. The pigments produced by C. gattii from d-tryptophan were distinct and were not related to melanin formation from 3,4-dihydroxyphenylalanine. Thin-layer chromatography of the methanol-extracted C. gattii cells detected four different pigments, including brown (two types), yellow, and pink-purple compounds. We conclude that tryptophan-derived pigments are not melanins and that growth on m-DTDP or YCB-DTDP agar can be used to rapidly differentiate C. gattii from C. neoformans. PMID:17989195

  4. Growth and pigment production on D-tryptophan medium by Cryptococcus gattii, Cryptococcus neoformans, and Candida albicans.

    PubMed

    Chaskes, Stuart; Frases, Susana; Cammer, Michael; Gerfen, Gary; Casadevall, Arturo

    2008-01-01

    Given the increasing prevalence of cryptococcosis caused by Cryptococcus gattii (serotypes B and C) strains, there is a need for rapid and reliable tests that discriminate C. gattii from Cryptococcus neoformans (serotypes A, D, and AD). Seventy-two C. neoformans strains, sixty-seven C. gattii strains, and five Candida albicans strains were analyzed for their ability to grow and produce pigment on minimal D-tryptophan D-proline (m-DTDP) medium, on yeast carbon base D-tryptophan D-proline (YCB-DTDP) medium, and on fructose D-tryptophan glycine (m-FDTG) medium. Of the C. gattii and C. neoformans isolates, 94% and 0% grew on m-DTDP agar, respectively, and 98% and 0% grew in YCB-DTDP medium, respectively. C. gattii produced large amounts of brown intracellular pigment(s) on m-DTDP agar and smaller amounts of yellow-brown (amber) extracellular pigment(s). C. albicans grew on both media and produced a pink photoactivated pigment on m-DTDP agar. C. gattii produced large amounts of brown intracellular pigments on the differential medium m-FDTG, whereas C. neoformans produced smaller amounts of the brown pigments and C. albicans produced a pink pigment. The pigments produced by C. gattii from D-tryptophan were distinct and were not related to melanin formation from 3,4-dihydroxyphenylalanine. Thin-layer chromatography of the methanol-extracted C. gattii cells detected four different pigments, including brown (two types), yellow, and pink-purple compounds. We conclude that tryptophan-derived pigments are not melanins and that growth on m-DTDP or YCB-DTDP agar can be used to rapidly differentiate C. gattii from C. neoformans.

  5. Growth and pigment production on D-tryptophan medium by Cryptococcus gattii, Cryptococcus neoformans, and Candida albicans.

    PubMed

    Chaskes, Stuart; Frases, Susana; Cammer, Michael; Gerfen, Gary; Casadevall, Arturo

    2008-01-01

    Given the increasing prevalence of cryptococcosis caused by Cryptococcus gattii (serotypes B and C) strains, there is a need for rapid and reliable tests that discriminate C. gattii from Cryptococcus neoformans (serotypes A, D, and AD). Seventy-two C. neoformans strains, sixty-seven C. gattii strains, and five Candida albicans strains were analyzed for their ability to grow and produce pigment on minimal D-tryptophan D-proline (m-DTDP) medium, on yeast carbon base D-tryptophan D-proline (YCB-DTDP) medium, and on fructose D-tryptophan glycine (m-FDTG) medium. Of the C. gattii and C. neoformans isolates, 94% and 0% grew on m-DTDP agar, respectively, and 98% and 0% grew in YCB-DTDP medium, respectively. C. gattii produced large amounts of brown intracellular pigment(s) on m-DTDP agar and smaller amounts of yellow-brown (amber) extracellular pigment(s). C. albicans grew on both media and produced a pink photoactivated pigment on m-DTDP agar. C. gattii produced large amounts of brown intracellular pigments on the differential medium m-FDTG, whereas C. neoformans produced smaller amounts of the brown pigments and C. albicans produced a pink pigment. The pigments produced by C. gattii from D-tryptophan were distinct and were not related to melanin formation from 3,4-dihydroxyphenylalanine. Thin-layer chromatography of the methanol-extracted C. gattii cells detected four different pigments, including brown (two types), yellow, and pink-purple compounds. We conclude that tryptophan-derived pigments are not melanins and that growth on m-DTDP or YCB-DTDP agar can be used to rapidly differentiate C. gattii from C. neoformans. PMID:17989195

  6. Antifungal Susceptibility Patterns of Candida Species Recovered from Endotracheal Tube in an Intensive Care Unit.

    PubMed

    Baghdadi, Elham; Khodavaisy, Sadegh; Rezaie, Sassan; Abolghasem, Sara; Kiasat, Neda; Salehi, Zahra; Sharifynia, Somayeh; Aala, Farzad

    2016-01-01

    Aims. Biofilms formed by Candida species which associated with drastically enhanced resistance against most antimicrobial agents. The aim of this study was to identify and determine the antifungal susceptibility pattern of Candida species isolated from endotracheal tubes from ICU patients. Methods. One hundred forty ICU patients with tracheal tubes who were intubated and mechanically ventilated were surveyed for endotracheal tube biofilms. Samples were processed for quantitative microbial culture. Yeast isolates were identified to the species level based on morphological characteristics and their identity was confirmed by PCR-RFLP. Antifungal susceptibility testing was determined according to CLSI document (M27-A3). Results. Ninety-five strains of Candida were obtained from endotracheal tubes of which C. albicans (n = 34; 35.7%) was the most frequently isolated species followed by other species which included C. glabrata (n = 24; 25.2%), C. parapsilosis (n = 16; 16.8%), C. tropicalis (n = 12; 12.6%), and C. krusei (n = 9; 9.4%). The resulting MIC90 for all Candida species were in increasing order as follows: caspofungin (0.5 μg/mL); amphotericin B (2 μg/mL); voriconazole (8.8 μg/mL); itraconazole (16 μg/mL); and fluconazole (64 μg/mL). Conclusion. Candida species recovered from endotracheal tube are the most susceptible to caspofungin.

  7. Antifungal Susceptibility Patterns of Candida Species Recovered from Endotracheal Tube in an Intensive Care Unit

    PubMed Central

    Baghdadi, Elham; Rezaie, Sassan; Abolghasem, Sara; Kiasat, Neda; Salehi, Zahra; Sharifynia, Somayeh

    2016-01-01

    Aims. Biofilms formed by Candida species which associated with drastically enhanced resistance against most antimicrobial agents. The aim of this study was to identify and determine the antifungal susceptibility pattern of Candida species isolated from endotracheal tubes from ICU patients. Methods. One hundred forty ICU patients with tracheal tubes who were intubated and mechanically ventilated were surveyed for endotracheal tube biofilms. Samples were processed for quantitative microbial culture. Yeast isolates were identified to the species level based on morphological characteristics and their identity was confirmed by PCR-RFLP. Antifungal susceptibility testing was determined according to CLSI document (M27-A3). Results. Ninety-five strains of Candida were obtained from endotracheal tubes of which C. albicans (n = 34; 35.7%) was the most frequently isolated species followed by other species which included C. glabrata (n = 24; 25.2%), C. parapsilosis (n = 16; 16.8%), C. tropicalis (n = 12; 12.6%), and C. krusei (n = 9; 9.4%). The resulting MIC90 for all Candida species were in increasing order as follows: caspofungin (0.5 μg/mL); amphotericin B (2 μg/mL); voriconazole (8.8 μg/mL); itraconazole (16 μg/mL); and fluconazole (64 μg/mL). Conclusion. Candida species recovered from endotracheal tube are the most susceptible to caspofungin.

  8. Antifungal Susceptibility Patterns of Candida Species Recovered from Endotracheal Tube in an Intensive Care Unit

    PubMed Central

    Baghdadi, Elham; Rezaie, Sassan; Abolghasem, Sara; Kiasat, Neda; Salehi, Zahra; Sharifynia, Somayeh

    2016-01-01

    Aims. Biofilms formed by Candida species which associated with drastically enhanced resistance against most antimicrobial agents. The aim of this study was to identify and determine the antifungal susceptibility pattern of Candida species isolated from endotracheal tubes from ICU patients. Methods. One hundred forty ICU patients with tracheal tubes who were intubated and mechanically ventilated were surveyed for endotracheal tube biofilms. Samples were processed for quantitative microbial culture. Yeast isolates were identified to the species level based on morphological characteristics and their identity was confirmed by PCR-RFLP. Antifungal susceptibility testing was determined according to CLSI document (M27-A3). Results. Ninety-five strains of Candida were obtained from endotracheal tubes of which C. albicans (n = 34; 35.7%) was the most frequently isolated species followed by other species which included C. glabrata (n = 24; 25.2%), C. parapsilosis (n = 16; 16.8%), C. tropicalis (n = 12; 12.6%), and C. krusei (n = 9; 9.4%). The resulting MIC90 for all Candida species were in increasing order as follows: caspofungin (0.5 μg/mL); amphotericin B (2 μg/mL); voriconazole (8.8 μg/mL); itraconazole (16 μg/mL); and fluconazole (64 μg/mL). Conclusion. Candida species recovered from endotracheal tube are the most susceptible to caspofungin. PMID:27642628

  9. Antifungal Susceptibility Patterns of Candida Species Recovered from Endotracheal Tube in an Intensive Care Unit.

    PubMed

    Baghdadi, Elham; Khodavaisy, Sadegh; Rezaie, Sassan; Abolghasem, Sara; Kiasat, Neda; Salehi, Zahra; Sharifynia, Somayeh; Aala, Farzad

    2016-01-01

    Aims. Biofilms formed by Candida species which associated with drastically enhanced resistance against most antimicrobial agents. The aim of this study was to identify and determine the antifungal susceptibility pattern of Candida species isolated from endotracheal tubes from ICU patients. Methods. One hundred forty ICU patients with tracheal tubes who were intubated and mechanically ventilated were surveyed for endotracheal tube biofilms. Samples were processed for quantitative microbial culture. Yeast isolates were identified to the species level based on morphological characteristics and their identity was confirmed by PCR-RFLP. Antifungal susceptibility testing was determined according to CLSI document (M27-A3). Results. Ninety-five strains of Candida were obtained from endotracheal tubes of which C. albicans (n = 34; 35.7%) was the most frequently isolated species followed by other species which included C. glabrata (n = 24; 25.2%), C. parapsilosis (n = 16; 16.8%), C. tropicalis (n = 12; 12.6%), and C. krusei (n = 9; 9.4%). The resulting MIC90 for all Candida species were in increasing order as follows: caspofungin (0.5 μg/mL); amphotericin B (2 μg/mL); voriconazole (8.8 μg/mL); itraconazole (16 μg/mL); and fluconazole (64 μg/mL). Conclusion. Candida species recovered from endotracheal tube are the most susceptible to caspofungin. PMID:27642628

  10. Overwintering of Vineyard Yeasts: Survival of Interacting Yeast Communities in Grapes Mummified on Vines

    PubMed Central

    Sipiczki, Matthias

    2016-01-01

    The conversion of grape must into wine involves the development and succession of yeast populations differing in species composition. The initial population is formed by vineyard strains which are washed into the must from the crushed grapes and then completed with yeasts coming from the cellar environment. As the origin and natural habitat of the vineyard yeasts are not fully understood, this study addresses the possibility, that grape yeasts can be preserved in berries left behind on vines at harvest until the spring of the next year. These berries become mummified during the winter on the vines. To investigate whether yeasts can survive in these overwintering grapes, mummified berries were collected in 16 localities in the Tokaj wine region (Hungary-Slovakia) in early March. The collected berries were rehydrated to recover viable yeasts by plating samples onto agar plates. For the detection of minority species which would not be detected by direct plating, an enrichment step repressing the propagation of alcohol-sensitive yeasts was also included in the process. The morphological, physiological, and molecular analysis identified 13 basidiomycetous and 23 ascomycetous species including fermentative yeasts of wine-making relevance among the 3879 isolates. The presence of viable strains of these species demonstrates that the grapes mummified on the vine can serve as a safe reservoir of yeasts, and may contribute to the maintenance of grape-colonizing yeast populations in the vineyard over years, parallel with other vectors and habitats. All basidiomycetous species were known phylloplane yeasts. Three Hanseniaspora species and pigmented Metschnikowia strains were the most frequent ascomycetes. Other fermentative yeasts of wine-making relevance were detected only in the enrichment cultures. Saccharomyces (S. paradoxus, S. cerevisiae, and S. uvarum) were recovered from 13% of the samples. No Candida zemplinina was found. The isolates with Aureobasidium morphology

  11. In Vitro and In Vivo Activity of a Novel Antifungal Small Molecule against Candida Infections

    PubMed Central

    Yuen, Kwok Yong; Wang, Yu; Yang, Dan; Samaranayake, Lakshman Perera

    2014-01-01

    Candida is the most common fungal pathogen of humans worldwide and has become a major clinical problem because of the growing number of immunocompromised patients, who are susceptible to infection. Moreover, the number of available antifungals is limited, and antifungal-resistant Candida strains are emerging. New and effective antifungals are therefore urgently needed. Here, we discovered a small molecule with activity against Candida spp. both in vitro and in vivo. We screened a library of 50,240 small molecules for inhibitors of yeast-to-hypha transition, a major virulence attribute of Candida albicans. This screening identified 20 active compounds. Further examination of the in vitro antifungal and anti-biofilm properties of these compounds, using a range of Candida spp., led to the discovery of SM21, a highly potent antifungal molecule (minimum inhibitory concentration (MIC) 0.2 – 1.6 µg/ml). In vitro, SM21 was toxic to fungi but not to various human cell lines or bacterial species and was active against Candida isolates that are resistant to existing antifungal agents. Moreover, SM21 was relatively more effective against biofilms of Candida spp. than the current antifungal agents. In vivo, SM21 prevented the death of mice in a systemic candidiasis model and was also more effective than the common antifungal nystatin at reducing the extent of tongue lesions in a mouse model of oral candidiasis. Propidium iodide uptake assay showed that SM21 affected the integrity of the cell membrane. Taken together, our results indicate that SM21 has the potential to be developed as a novel antifungal agent for clinical use. PMID:24465737

  12. In vitro and in vivo activity of a novel antifungal small molecule against Candida infections.

    PubMed

    Wong, Sarah Sze Wah; Kao, Richard Yi Tsun; Yuen, Kwok Yong; Wang, Yu; Yang, Dan; Samaranayake, Lakshman Perera; Seneviratne, Chaminda Jayampath

    2014-01-01

    Candida is the most common fungal pathogen of humans worldwide and has become a major clinical problem because of the growing number of immunocompromised patients, who are susceptible to infection. Moreover, the number of available antifungals is limited, and antifungal-resistant Candida strains are emerging. New and effective antifungals are therefore urgently needed. Here, we discovered a small molecule with activity against Candida spp. both in vitro and in vivo. We screened a library of 50,240 small molecules for inhibitors of yeast-to-hypha transition, a major virulence attribute of Candida albicans. This screening identified 20 active compounds. Further examination of the in vitro antifungal and anti-biofilm properties of these compounds, using a range of Candida spp., led to the discovery of SM21, a highly potent antifungal molecule (minimum inhibitory concentration (MIC) 0.2-1.6 µg/ml). In vitro, SM21 was toxic to fungi but not to various human cell lines or bacterial species and was active against Candida isolates that are resistant to existing antifungal agents. Moreover, SM21 was relatively more effective against biofilms of Candida spp. than the current antifungal agents. In vivo, SM21 prevented the death of mice in a systemic candidiasis model and was also more effective than the common antifungal nystatin at reducing the extent of tongue lesions in a mouse model of oral candidiasis. Propidium iodide uptake assay showed that SM21 affected the integrity of the cell membrane. Taken together, our results indicate that SM21 has the potential to be developed as a novel antifungal agent for clinical use. PMID:24465737

  13. Candida theae sp. nov., a new anamorphic beverage-associated member of the Lodderomyces clade.

    PubMed

    Chang, Chin-Feng; Lin, Yu-Ching; Chen, Shan-Fu; Carvajal Barriga, Enrique Javier; Carvaja Barriga, Enrique Javier; Barahona, Patricia Portero; James, Stephen A; Bond, Christopher J; Roberts, Ian N; Lee, Ching-Fu

    2012-02-01

    Four strains representing a novel yeast species belonging to the genus Candida were independently isolated in Taiwan and Ecuador. Two strains (G17(T) and G31) were isolated in Taiwan, by pellet precipitation from plastic-bottled tea drinks produced in Indonesia, while two additional strains (CLQCA 10-049 and CLQCA 10-062) were recovered from ancient chicha fermentation vessels found in tombs in Quito, Ecuador. These four strains were morphologically, and phylogenetically identical to each other. No sexual reproduction was observed on common sporulation media. Large-subunit (LSU) rRNA gene sequence analysis revealed the four strains to belong to the Lodderomyces clade, closely related to members of the Candida parapsilosis species complex. The four strains, which have identical LSU D1/D2 sequences, differ from their closest phylogenetic neighbors, Candida orthopsilosis and Candida parapsilosis, by 6-9 nt substitutions, respectively. Physiologically, the four strains are similar to Candida parapsilosis, although they can be distinguished from their closest relative by the assimilation of arbutin, nitrite, and creatine. The Indonesian and Ecuadorian strain sets can also be distinguished from one another based on ITS sequencing, differing by 4 substitutions in ITS1 and 1 single nucleotide indel in ITS2. Collectively, the results indicate that the four strains represent a previously unrecognized species of Candida. The name Candida theae sp. nov. is proposed to accommodate these strains, with G-17(T) (BCRC 23242(T)=CBS 12239(T)=ATCC MYA-4746(T)) designated as the type strain. PMID:22088606

  14. Predisposing conditions for Candida spp. carriage in the oral cavity of denture wearers and individuals with natural teeth.

    PubMed

    Lyon, Juliana Pereira; da Costa, Sérgio Carvalho; Totti, Valéria Maria Gomes; Munhoz, Maira Forestti Vieira; de Resende, Maria Aparecida

    2006-05-01

    Candida species are a normal commensal present in a large percentage of healthy individuals. Denture wearers are predisposed to the development of candidosis and to the presence of Candida spp. The presence of the yeast, even in healthy subjects, should be considered more carefully. We investigated the prevalence of Candida spp. in 112 denture wearers and 103 individuals with natural teeth, patients from the clinic of total prosthesis of the Dental School of the Federal University of Minas Gerais, Brazil, and from the School of Pharmacy and Dentistry of Alfenas, Brazil. Factors like gender, age over 60 years, low education, and xerostomia were directly associated with the presence of Candida yeasts at a significance level of 5% (p > 0.05). However, the major predisposing factor for the carrier state was wearing dentures (p = 0.001). Candida isolates were identified using morphological and biochemical profiles. Seventy-one isolates were identified as C. albicans (65.1%), 15 as C. glabrata (13.7%), 8 as C. parapsilosis (7.3%), 3 as C. krusei (2.7%), and 12 as C. tropicalis (11.0%). Susceptibility testing to fluconazole and itraconazole was also performed with the strains obtained. Both drugs showed a strong inhibition against most oral isolates.

  15. Antarctic Yeasts: Biodiversity and Potential Applications

    NASA Astrophysics Data System (ADS)

    Shivaji, S.; Prasad, G. S.

    This review is an attempt in cataloguing the diversity of yeasts in Antarctica, highlight their biotechnological potential and understand the basis of adaptation to low temperature. As of now several psychrophilic and psychrotolerant yeasts from Antarctic soils and marine waters have been characterized with respect to their growth characteristics, ecological distribution and taxonomic significance. Interestingly most of these species belonged to basidiomycetous yeasts which as a group are known for their ability to circumvent and survive under stress conditions. Simultaneously their possible role as work horses in the biotechnological industry was recognized due to their ability to produce novel enzymes and biomolecules such as agents for the breakdown of xenobiotics, and novel pharmaceutical chemi cals. The high activity of psychrophilic enzymes at low and moderate temperatures offers potential economic benefits. As of now lipases from Pseudozyma antarctica have been extensively studied to understand their unique thermal stability at 90°C and also because of its use in the pharmaceutical, agriculture, food, cosmetics and chemical industry. A few of the other enzymes which have been studied include extracellular alpha-amylase and glucoamylase from the yeast Pseudozyma antarctica (Candida antarctica), an extra-cellular protease from Cryptococcus humicola, an aspartyl proteinase from Cryptococcus humicola, a novel extracellular subtilase from Leucosporidium antarcticum, and a xylanase from Cryptococcus adeliensis

  16. 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.

  17. Methanol simplifies gas processing

    SciTech Connect

    Minkkinen, A.; Jonchere, J.P.

    1997-12-31

    Recent development of a simple single solvent technology goes far to meet the complete gas processing needs. The use of methanol, as practiced in the IPFEXOL process, where it is used not only as a hydrate inhibitor and antifreeze agent but as an acid gas extraction solvent makes the complete gas processing scheme simple and probably the most cost effective as well. This paper presents several gas processing applications where water, hydrocarbon liquids and acid gases are removed from natural wellhead production gases. Water and hydrocarbon liquids removal is achieved to the extent necessary to make a pipeline transportable gas or meet downstream cryogenic processing demands. These are illustrated with recent applications of the IFPEX-1 process successfully operating today in North America and the Far East. A recent North Sea offshore project is highlighted showing the particular advantages in offshore applications. For the removal of water and hydrocarbon liquids together with a substantial quantity of not only CO{sub 2} but H{sub 2}S, the most complete methanol use scheme is presented. This is illustrated with the development of an advanced version of the IFPEX-2 process containing some innovative but simple equipment concepts which yields high pressure dry acid gases for reinjection or a high quality acid gas destined to Claus type sulfur recovery.

  18. 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

  19. [The yeast community associated with the digestive tract of the German cockroach Blattella germanica L].

    PubMed

    Zheltikova, T M; Glushakova, A M; Alesho, N A

    2011-01-01

    Data on the yeasts colonizing the digestive tract ofa German cockroach have been first obtained. Cockroach cultures are used in the commercial production of allergy vaccines to treat patients sensitized to cockroach allergens. The enteric microflora of the insects can bring nonshared antigens into the composition of the agents manufactured. An investigation established that out of 10 yeast species isolated from the digestive tract of the cockroaches fed sterile food, 6 species (Candida glabrata, Cryptococcus magnus, Debaryomyces hansenii, Metschikowia pulcherrima, Phodo-torula glutinis, Rhodotorula mucilaginosa) were isolated from both the digestive tract and excrements and 4 (Candida oleophila, Candida shehatae, Cryptococcus albidus, Pichia membmnaefciens) were only from the digestive tract. It seems that the yeast is either digested or inactivated in the digestive tract of the insects and loses their capacity to grow When the cockroaches were fed sterile food for a long time (at least a month), all yeasts virtually disappeared from the digestive tract of the insects except for Candida glabrata, C.shehatae, and Rh.mucilaginosa. However, only C.glabrata achieved a great deal (10(7)-10(8) CFU/g) of cockroaches (both imagoes and larvae of 5-7 ages), which statistically significantly decreased by no less than three orders of magnitude in the excrements after passing through the digestive tract.

  20. Microdilution in vitro Antifungal Susceptibility Patterns of Candida Species, From Mild Cutaneous to Bloodstream Infections

    PubMed Central

    Rezazadeh, Elham; Sabokbar, Azar; Moazeni, Maryam; Rezai, Mohammad Sadegh; Badali, Hamid

    2016-01-01

    Background Candida species, as opportunistic organisms, can cause various clinical manifestations, ranging from mild cutaneous infections to systemic candidiasis in otherwise healthy individuals. Remarkably, the incidence and mortality rates of candidemia have significantly increased worldwide, even after advances in medical interventions and the development of novel antifungal drugs. Objectives Given the possible resistance to antifungal agents, susceptibility testing can be useful in defining the activity spectrum of antifungals and determining the appropriate treatment regime. Materials and Methods The in vitro susceptibilities of molecularly identified Candida strains (n = 150) belonging to seven species recovered from clinical specimens, including vaginal, cutaneous, sputum, bronchoalveolar lavage (BAL), and blood samples, were determined for six antifungal drugs (amphotericin B, fluconazole, itraconazole, voriconazole, posaconazole, and caspofungin), based on the clinical and laboratory standards institute’s M27-A3 and M27-S4 documents. Results Candida albicans was the most frequently isolated species (44.66%), followed by non-albicans Candida, including C. glabrata (20%), C. parapsilosis (13.33%), C. krusei (8%), C. tropicalis (7.3%), C. dubliniensis (4%), and C. africana (3.33%). Posaconazole had the lowest geometric mean minimum inhibitory concentration (MIC) (0.0122 µg/ml), followed by amphotericin B (0.0217 µg/mL), voriconazole (0.1022 µg/mL), itraconazole (0.1612 µg/mL), caspofungin (0.2525 µg/mL), and fluconazole (0.4874 µg/mL) against all isolated Candida species. Candida africana and C. parapsilosis were significantly more susceptible to fluconazole, compared to C. albicans and other Candida species (P < 0.001). However, their clinical effectiveness in the treatment of Candida infections remains to be determined. Conclusions These findings highlight the importance of precise and correct species identification of clinical yeast isolates via

  1. Candida biofilms: is adhesion sexy?

    PubMed

    Soll, David R

    2008-08-26

    The development of Candida albicans biofilms requires two types of adhesion molecule - the Als proteins and Hwp1. Mutational analyses have recently revealed that these molecules play complementary roles, and their characteristics suggest that they may have evolved from primitive mating agglutinins.

  2. Candida biofilms: is adhesion sexy?

    PubMed

    Soll, David R

    2008-08-26

    The development of Candida albicans biofilms requires two types of adhesion molecule - the Als proteins and Hwp1. Mutational analyses have recently revealed that these molecules play complementary roles, and their characteristics suggest that they may have evolved from primitive mating agglutinins. PMID:18727911

  3. Candida lusitaniae causing fatal meningitis.

    PubMed Central

    Sarma, P. S.; Durairaj, P.; Padhye, A. A.

    1993-01-01

    Fatal meningitis due to Candida lusitaniae in a 35 year old previously healthy man is described. C. lusitaniae is an opportunistic fungal pathogen reported infrequently in the English literature. This is the third case report of meningitis and the first fatal infection in an adult from Central India due to C. lusitaniae known to the authors. PMID:8290437

  4. Candida infections among neutropenic patients

    PubMed Central

    Mohammadi, Rasoul; Foroughifar, Elham

    2016-01-01

    Background: Systemic candidiasis is a major complication in neutropenic cancer patients undergoing treatment. Most systemic fungal infections emerge from endogenous microflora so the aim of the present study was to identify Candida species isolated from the different regions of body in neutropenic patients in compare with the control group. Methods: A total of 309 neutropenic cancer patients and 584 patients without cancer (control group) entered in the study. Molecular identification of clinical isolates was performed by PCR-RFLP technique. Results: Twenty-two out of 309 patients had candidiasis (7.1%). Male to female ratio was 1/1 and age ranged from 23 to 66 years. Colorectal cancer and acute myeloid leukemia (AML) were the most common cancers. Candida albicans was the most prevalent Candida species among neutropenic patients (50%) and control group (57.9%). Mortality rate in cancer patients was 13.6% in comparison with control group (5.2%). Conclusion: Since candidiasis is an important cause of morbidity and mortality in neutropenic patients, precise identification of Candida species by molecular techniques can be useful for the appropriate selection of antifungal drugs particularly in high risk patients. PMID:27386056

  5. Biodegradation and decolorization of melanoidin solutions by manganese peroxidase yeasts.

    PubMed

    Mahgoub, Samir; Tsioptsias, Costas; Samaras, Petros

    2016-01-01

    The ability of selected manganese peroxidase (MnP) yeast strains, isolated from the mixed liquor of an activated sludge bioreactor treating melanoidins wastewater, was investigated in this work, aiming to examine the degradation potential of melanoidins, in the presence or absence of nutrients. Ten yeast strains were initially isolated from the mixed liquor; four yeast strains (Y1, Y2, Y3 and Y4) were selected for further studies, based on their tolerance towards synthetic melanoidins (SMs) degradation and MnP activity onto solid agar medium. The Y1 strain exhibited almost 98% homology to Candida glabrata yeast, based on 28S rRNA identification studies. During experiments carried out using SM at 30 °C, the four isolated yeast cultures showed a noticeable organic matter reduction and decolorization capacity reaching up to 70% within 2-5 days. However, the corresponding yeast cultures grown in glucose peptone yeast extract medium using real melanoidin wastewater at 30°C showed lower organic matter and color removal capacity, reaching about 60% within 2-5 days. Nevertheless, it was found that the removal of real and synthetic melanoidins could be carried out by these strains under non-aseptic conditions, without requiring further addition of nutrients. PMID:27191565

  6. Genetic and physiological variants of yeast selected from palm wine.

    PubMed

    Ezeronye, O U; Okerentugba, P O

    2001-01-01

    Genetic screening of 1200-palm wine yeasts lead to the selection of fourteen isolates with various genetic and physiological properties. Nine of the isolates were identified as Saccharamyces species, three as Candida species, one as Schizosaccharomyces species and one as Kluyveromyces species. Five of the isolates were wild type parents, two were respiratory deficient mutants (rho) and nine were auxotrophic mutants. Four isolates were heterozygous diploid (alphaa) and two were homozygous diploid (aa/alphaalpha) for the mating a mating types were further identified on mating with type loci. Four Mat alpha and four Mat a types were further identified on mating with standard haploid yeast strains. Forty-five percent sporulated on starvation medium producing tetrads. Fifty-two percent of the four-spored asci contained four viable spores. Maximum specific growth rate [micromax] of the fourteen isolates range from 0.13-0.26, five isolates were able to utilize exogenous nitrate for growth. Percentage alcohol production range between 5.8-8.8% for palm wine yeast, 8.5% for bakers' yeast and 10.4% for brewers yeast. The palm wine yeast were more tolerant to exogenous alcohol but had a low alcohol productivity. Hybridization enhanced alcohol productivity and tolerance in the palm wine yeasts.

  7. Studies on the yeast flora in patients suffering from psoriasis capillitii or seborrhoic dermatitis of the scalp.

    PubMed

    Senff, H; Bothe, C; Busacker, J; Reinel, D

    1990-01-01

    In 65 patients with scalp psoriasis or seborrhoic dermatitis of the scalp, stool specimens, tongue swabs and scalp scales were examined for yeasts. The stool specimens showed in 70.8% of the patient group massive and in 7.7% moderate yeast colonization. Yeasts were found in 47.7% of the tongue cultures and in 12.5% of the scalp scales. Candida albicans was the predominant pathogen in the faeces and on the tongue. In comparison with a control group, frequency of yeasts in faeces and on the tongue in patients with psoriasis capillitii and seborrhoic dermatitis of the scalp could be shown to be significantly higher.

  8. Prosthetic joint infections with osteomyelitis due to Candida albicans.

    PubMed

    Lerch, K; Kalteis, T; Schubert, T; Lehn, N; Grifka, J

    2003-12-01

    We report the case of a 78-year-old woman who suffered from a severe soft tissue and bone infection of her left knee 3 years after a total knee-joint replacement without loosening of her endoprosthesis. Cultures from joint aspiration and tissue specimen identified Staphylococcus aureus and Candida albicans. Direct microscopic examination of vital spongy bone and fibrous tissue revealed microabscesses and seeds of yeasts inside the fatty marrow and interface. After removal of the prosthesis several soft tissue and bone specimens were taken during planned re-operations. The histological examination showed no morphological changing, no reduction or extinction of the yeast cells under fluconazole therapy with a dosage of 6 mg kg(-1) body weight (400 mg daily). Curing of the fungal infection with eradication of the yeasts in the bony specimens was achieved with higher doses of 12 mg kg(-1) body weight (800 mg day(-1)) over a 2 month regimen in combination with repeated surgical debridements.

  9. [Molecular mechanisms of peroxisome biogenesis in yeasts].

    PubMed

    Sibirnyĭ, A A

    2012-01-01

    Peroxisomes contain oxidases generating hydrogen peroxide, and catalase degrading this toxic compound. Another characteristic function of each eukaryotic peroxisome, from yeast to man, is fatty acid beta-oxidation. However, in peroxisomes a variety of other metabolic pathways are located. In fungi, peroxisomes contain enzymes involved in catabolism of unusual carbon and nitrogen sources (methanol, purines, D-amino acids, pipecolynic acid, sarcosine, glycolate, spermidine etc) as well as biosynthesis of lysine in yeasts and penicillin in mycelial fungi. Impairment of peroxisomal structure and functions causes many human disorders. The similar defects have been identified in yeast mutants defective in peroxisomal biogenesis. Peroxisomal biogenesis is actively studied during last two decades using uni- and multicellular model systems. It was observed that many aspects of peroxisomal biogenesis and proteins involved in this process display striking similarity between all eukaryotes, from yeasts to humans. Yeast is a convenient model system for this kind of research. Current review summarizes data on molecular events of peroxisomal biogenesis, functions of peroxine proteins, import of peroxisomal matrix and membrane proteins and on mechanisms of peroxisomedivision and inheritance. PMID:22642098

  10. Hematogenous dissemination of Candida dubliniensis causing spondylodiscitis and spinal abscess in a HIV-1 and HCV-coinfected patient

    PubMed Central

    Salzer, Helmut J.F.; Rolling, Thierry; Klupp, Eva-Maria; Schmiedel, Stefan

    2015-01-01

    We report a case of spondylodiscitis and spinal abscess following haematogenous dissemination of the emerging yeast Candida dubliniensis in a human immunodeficiency virus-1 (HIV-1) and hepatitis C virus (HCV)-coinfected patient. Although C. dubliniensis is considered less virulent compared to its closest known relative Candida albicans, reports of severe fungal infections are increasing. This case indicates that the pathogenicity of C. dubliniensis may be higher than previously believed. Therefore fungal infections caused by this dimorph fungus should be kept in mind in immunocompromised patients with spondylodiscitis and spinal abscess. PMID:25750857

  11. Isolation and characterization of phenol degrading yeasts from wastewater in the coking plant of Zarand, Kerman

    PubMed Central

    Karimi, Maryam; Hassanshahian, Mehdi

    2016-01-01

    Phenol and phenolic compounds are environmental pollutants present in industrial wastewaters such as coal tar, oil refineries and petrochemical plants. Phenol removal from industrial effluents is extremely important for the protection of environment. Usually, phenol degradation is carried out by physicochemical methods that are costly and produce hazardous metabolites. Recently, phenol biodegradation has been considered. Yeasts are the most important phenol biodegraders. In this study, the phenol-degrading yeast from environmental samples (soil and wastewater) was isolated from the coking plant of Zarand, Kerman. Then total heterotrophic yeasts were counted. The soil samples had higher rates of yeast degrader, in comparison to wastewater samples. After three passages, four yeasts (K1, K2, K7 and K11) that had the highest growth rate were selected for further study. Also, these yeasts were able to remove phenol measured by Gibbs reagent. The effect of four different concentrations of phenol (50, 125, 200 and 275) mg L−1 was measured and three degradation patterns in these yeasts were observed. The hydrophobicity and emulsification activity were measured in all eleven yeasts. Finally, strong yeasts in phenol degrading yeasts were identified by molecular method using amplification of 18S rRNA gene region. The sequencing results showed that these isolated yeasts belonged to Candida tropicalis strain K1, Pichia guilliermondii strain K2, Meyerozyma guilliermondii strain K7 and C. tropicalis strain K11. PMID:26887222

  12. Isolation and characterization of phenol degrading yeasts from wastewater in the coking plant of Zarand, Kerman.

    PubMed

    Karimi, Maryam; Hassanshahian, Mehdi

    2016-01-01

    Phenol and phenolic compounds are environmental pollutants present in industrial wastewaters such as coal tar, oil refineries and petrochemical plants. Phenol removal from industrial effluents is extremely important for the protection of environment. Usually, phenol degradation is carried out by physicochemical methods that are costly and produce hazardous metabolites. Recently, phenol biodegradation has been considered. Yeasts are the most important phenol biodegraders. In this study, the phenol-degrading yeast from environmental samples (soil and wastewater) was isolated from the coking plant of Zarand, Kerman. Then total heterotrophic yeasts were counted. The soil samples had higher rates of yeast degrader, in comparison to wastewater samples. After three passages, four yeasts (K1, K2, K7 and K11) that had the highest growth rate were selected for further study. Also, these yeasts were able to remove phenol measured by Gibbs reagent. The effect of four different concentrations of phenol (50, 125, 200 and 275) mgL(-1) was measured and three degradation patterns in these yeasts were observed. The hydrophobicity and emulsification activity were measured in all eleven yeasts. Finally, strong yeasts in phenol degrading yeasts were identified by molecular method using amplification of 18S rRNA gene region. The sequencing results showed that these isolated yeasts belonged to Candida tropicalis strain K1, Pichia guilliermondii strain K2, Meyerozyma guilliermondii strain K7 and C. tropicalis strain K11.

  13. Isolation of Candida species on media with and without added fluconazole reveals high variability in relative growth susceptibility phenotypes.

    PubMed Central

    Schoofs, A; Odds, F C; Colebunders, R; Ieven, M; Wouters, L; Goossens, H

    1997-01-01

    Mouthwashes from human immunodeficiency virus-positive individuals were sampled for yeasts by direct plating on a differential agar medium with and without added fluconazole and via enrichment broths with and without added fluconazole. The colonies of the yeasts isolated were tested for relative growth in the presence of single concentrations of itraconazole and fluconazole. Among 258 culture plates containing yeasts obtained via different isolation routes from 86 yeast-positive samples, 33 (12.7%) of the plates showed unexpectedly high colony-to-colony variation in relative growth. Intercolony variation was seen in 41 (47.7%) of the 86 isolates when relative growth data were analyzed for all colonies of an isolate tested, regardless of the medium used for isolation. The prevalence of relative growth variability with the azoles was highest for Candida glabrata (100% of 13 isolates), followed by Candida krusei (60% of 5 isolates) and Candida albicans (40% of 53 isolates), and the visual patterns of variability seen in scatter plots of the data showed species specificity. Relative growth phenotypes generally tended to be stable for each yeast colony in subcultures, whether or not the medium used for subculture contained antifungal agents. DNA fingerprinting of stable and variable C. albicans isolates showed changes in band patterns detected with the probe Ca3, suggesting that the variability may have resulted from selection of different subtypes of the yeasts during the isolation procedure. These findings suggest that the yeasts isolated from single clinical samples were often not clonal in nature. The relative growth test revealed colony variability more readily than conventional susceptibility testing. PMID:9257732

  14. Lipid raft involvement in yeast cell growth and death.

    PubMed

    Mollinedo, Faustino

    2012-01-01

    The notion that cellular membranes contain distinct microdomains, acting as scaffolds for signal transduction processes, has gained considerable momentum. In particular, a class of such domains that is rich in sphingolipids and cholesterol, termed as lipid rafts, is thought to compartmentalize the plasma membrane, and to have important roles in survival and cell death signaling in mammalian cells. Likewise, yeast lipid rafts are membrane domains enriched in sphingolipids and ergosterol, the yeast counterpart of mammalian cholesterol. Sterol-rich membrane domains have been identified in several fungal species, including the budding yeast Saccharomyces cerevisiae, the fission yeast Schizosaccharomyces pombe as well as the pathogens Candida albicans and Cryptococcus neoformans. Yeast rafts have been mainly involved in membrane trafficking, but increasing evidence implicates rafts in a wide range of additional cellular processes. Yeast lipid rafts house biologically important proteins involved in the proper function of yeast, such as proteins that control Na(+), K(+), and pH homeostasis, which influence many cellular processes, including cell growth and death. Membrane raft constituents affect drug susceptibility, and drugs interacting with sterols alter raft composition and membrane integrity, leading to yeast cell death. Because of the genetic tractability of yeast, analysis of yeast rafts could be an excellent model to approach unanswered questions of mammalian raft biology, and to understand the role of lipid rafts in the regulation of cell death and survival in human cells. A better insight in raft biology might lead to envisage new raft-mediated approaches to the treatment of human diseases where regulation of cell death and survival is critical, such as cancer and neurodegenerative diseases.

  15. Lipid raft involvement in yeast cell growth and death

    PubMed Central

    Mollinedo, Faustino

    2012-01-01

    The notion that cellular membranes contain distinct microdomains, acting as scaffolds for signal transduction processes, has gained considerable momentum. In particular, a class of such domains that is rich in sphingolipids and cholesterol, termed as lipid rafts, is thought to compartmentalize the plasma membrane, and to have important roles in survival and cell death signaling in mammalian cells. Likewise, yeast lipid rafts are membrane domains enriched in sphingolipids and ergosterol, the yeast counterpart of mammalian cholesterol. Sterol-rich membrane domains have been identified in several fungal species, including the budding yeast Saccharomyces cerevisiae, the fission yeast Schizosaccharomyces pombe as well as the pathogens Candida albicans and Cryptococcus neoformans. Yeast rafts have been mainly involved in membrane trafficking, but increasing evidence implicates rafts in a wide range of additional cellular processes. Yeast lipid rafts house biologically important proteins involved in the proper function of yeast, such as proteins that control Na+, K+, and pH homeostasis, which influence many cellular processes, including cell growth and death. Membrane raft constituents affect drug susceptibility, and drugs interacting with sterols alter raft composition and membrane integrity, leading to yeast cell death. Because of the genetic tractability of yeast, analysis of yeast rafts could be an excellent model to approach unanswered questions of mammalian raft biology, and to understand the role of lipid rafts in the regulation of cell death and survival in human cells. A better insight in raft biology might lead to envisage new raft-mediated approaches to the treatment of human diseases where regulation of cell death and survival is critical, such as cancer and neurodegenerative diseases. PMID:23087902

  16. Marine culturable yeasts in deep-sea hydrothermal vents: species richness and association with fauna.

    PubMed

    Burgaud, Gaëtan; Arzur, Danielle; Durand, Lucile; Cambon-Bonavita, Marie-Anne; Barbier, Georges

    2010-07-01

    Investigations of the diversity of culturable yeasts at deep-sea hydrothermal sites have suggested possible interactions with endemic fauna. Samples were collected during various oceanographic cruises at the Mid-Atlantic Ridge, South Pacific Basins and East Pacific Rise. Cultures of 32 isolates, mostly associated with animals, were collected. Phylogenetic analyses of 26S rRNA gene sequences revealed that the yeasts belonged to Ascomycota and Basidiomycota phyla, with the identification of several genera: Rhodotorula, Rhodosporidium, Candida, Debaryomyces and Cryptococcus. Those genera are usually isolated from deep-sea environments. To our knowledge, this is the first report of yeasts associated with deep-sea hydrothermal animals.

  17. Use of the BioGRID Database for Analysis of Yeast Protein and Genetic Interactions.

    PubMed

    Oughtred, Rose; Chatr-aryamontri, Andrew; Breitkreutz, Bobby-Joe; Chang, Christie S; Rust, Jennifer M; Theesfeld, Chandra L; Heinicke, Sven; Breitkreutz, Ashton; Chen, Daici; Hirschman, Jodi; Kolas, Nadine; Livstone, Michael S; Nixon, Julie; O'Donnell, Lara; Ramage, Lindsay; Winter, Andrew; Reguly, Teresa; Sellam, Adnane; Stark, Chris; Boucher, Lorrie; Dolinski, Kara; Tyers, Mike

    2016-01-01

    The BioGRID database is an extensive repository of curated genetic and protein interactions for the budding yeast Saccharomyces cerevisiae, the fission yeast Schizosaccharomyces pombe, and the yeast Candida albicans SC5314, as well as for several other model organisms and humans. This protocol describes how to use the BioGRID website to query genetic or protein interactions for any gene of interest, how to visualize the associated interactions using an embedded interactive network viewer, and how to download data files for either selected interactions or the entire BioGRID interaction data set. PMID:26729909

  18. Use of the BioGRID Database for Analysis of Yeast Protein and Genetic Interactions.

    PubMed

    Oughtred, Rose; Chatr-aryamontri, Andrew; Breitkreutz, Bobby-Joe; Chang, Christie S; Rust, Jennifer M; Theesfeld, Chandra L; Heinicke, Sven; Breitkreutz, Ashton; Chen, Daici; Hirschman, Jodi; Kolas, Nadine; Livstone, Michael S; Nixon, Julie; O'Donnell, Lara; Ramage, Lindsay; Winter, Andrew; Reguly, Teresa; Sellam, Adnane; Stark, Chris; Boucher, Lorrie; Dolinski, Kara; Tyers, Mike

    2016-01-04

    The BioGRID database is an extensive repository of curated genetic and protein interactions for the budding yeast Saccharomyces cerevisiae, the fission yeast Schizosaccharomyces pombe, and the yeast Candida albicans SC5314, as well as for several other model organisms and humans. This protocol describes how to use the BioGRID website to query genetic or protein interactions for any gene of interest, how to visualize the associated interactions using an embedded interactive network viewer, and how to download data files for either selected interactions or the entire BioGRID interaction data set.

  19. Candida biotypes in patients with oral leukoplakia and lichen planus. Candida biotypes in leukoplakia and lichen planus.

    PubMed

    Lipperheide, V; Quindós, G; Jiménez, Y; Pontón, J; Bagán-Sebastián, J V; Aguirre, J M

    1996-01-01

    Prevalence of yeasts in 35 leukoplakia and 34 oral lichen planus patients was compared with that observed in persons without oral diseases. Serotype and morphotype were determined on Candida albicans isolates. Yeasts were isolated from the oral cavity specimens of 43.7% of the patients. C. albicans (serotype A) was the predominant species (76% in leukoplakia, 88.2% in lichen planus and 60.8% in healthy persons). Sixteen morphotypes were encountered on malt extract agar, being 732, 733, 734, 753 and 754 the most frequently found. Morphotypes SP1N and SP1Y were the most common on Sabouraud-trypheniltetrazolium agar (68.4% of the isolates from leukoplakia and 73.3% from lichen planus, but only 46.6% of the isolates from healthy oral mucosa showed SP1N morphotype). Presence of oral lesions was associated with a marked reduction in the yeast species and C. albicans biotypes, suggesting that C. albicans and particularly some of its biotypes, show a high potential of adaptation to the changes associated with the development of oral leukoplakia and lichen planus.

  20. OTEC energy via methanol production

    SciTech Connect

    Avery, W.H.; Richards, D.; Niemeyer, W.G.; Shoemaker, J.D.

    1983-01-01

    The conceptual design of an 160 MW/sub e/ OTEC plantship has been documented; it is designed to produce 1000 tonne/day of fuel-grade methanol from coal slurry shipped to the plantship, using oxygen and hydrogen from the on-board electrolysis of water. Data and components are used that were derived by Brown and Root Development, Inc. (BARDI) in designing a barge-mounted plant to make methanol from natural gas for Litton Industries and in the design and construction of a coal-to-ammonia demonstration plant in operation at Muscle Shoals, Alabama, for the Tennessee Valley Authority (TVA). The OTEC-methanol plant design is based on the use of the Texaco gasifier and Lurgi synthesis units. The sale price of OTEC methanol delivered to port from this first-of-a-kind plant is estimated to be marginally competitive with methanol from other sources at current market prices.