Candida Sorbophila Research Articles

Integrated analysis of the transcriptome and its interaction with the metabolome in metabolic associated fatty liver disease: Gut microbiome signatures, correlation networks, and effect of PNPLA3 genotype.

Interactions between communities of the gut microbiome and with the host could affect the onset and progression of metabolic associated fatty liver disease (MAFLD), and can be useful as new diagnostic and prognostic biomarkers. In this study, we performed a multi-omics approach to unravel gut microbiome signatures from 32 biopsy-proven patients (10 simple steatosis -SS- and 22 steatohepatitis -SH-) and 19 healthy volunteers (HV). Human and microbial transcripts were differentially identified between groups (MAFLD vs. HV/SH vs. SS), and analyzed for weighted correlation networks together with previously detected metabolites from the same set of samples. We observed that expression of Desulfobacteraceae bacterium, methanogenic archaea, Mushu phage, opportunistic pathogenic fungi Fusarium proliferatum and Candida sorbophila, protozoa Blastocystis spp. and Fonticula alba were upregulated in MAFLD and SH. Desulfobacteraceae bacterium and Mushu phage were hub species in the onset of MAFLD, whereas the activity of Fonticula alba, Faecalibacterium prausnitzii, and Mushu phage act as key regulators of the progression to SH. A combination of clinical, metabolomic, and transcriptomic parameters showed the highest predictive capacity for MAFLD and SH (AUC=0.96). In conclusion, faecal microbiome markers from several community members contribute to the switch in signatures characteristic of MAFLD and its progression towards SH.

Characterization of the newly isolated ω-oxidizing yeast Candida sorbophila DS02 and its potential applications in long-chain dicarboxylic acid production.

α, ω-Dicarboxylic acids (DCAs) are multipurpose chemicals widely used in polymers, perfumes, plasticizers, lubricants, and adhesives. The biotransformation of DCAs from alkanes and fatty acids by microorganisms has attracted recent interest, since synthesis via chemical oxidation causes problems in terms of the environment and safety. We isolated an ω-oxidizing yeast from a wastewater disposal facility of a petrochemical factory by chemostat enrichment culture. The haploid strain identified as Candida sorbophila DS02 grew on glucose and dodecane, exhibiting greater cell shrinkage on the latter. In flask cultures with mixed alkanes (C10-16) and fatty acid methyl esters (C10-16), DS02 used mixed alkanes simultaneously unlike Candida tropicalis and Yarrowia lipolytica and showed high substrate resistance. In flask cultures with acrylic acid-a known inhibitor of β-oxidation-DS02 produced 0.28g/l dodecanedioic acid (DDDA) from dodecane, similar to wild-type C. tropicalis ATCC 20336. In fed-batch fermentation, DS02 produced 9.87g/l DDDA, which was 5.7-fold higher than wild-type C. tropicalis. These results suggest that C. sorbophila strain DS02 has potential applications for the large-scale production of DCA.

Wickerhamiella slavikovae sp. nov. and Wickerhamiella goesii sp. nov., two yeast species isolated from natural substrates

Two novel yeast species were isolated during three independent studies of yeasts associated with natural substrates in Brazil and Taiwan. Analysis of the sequences of the D1/D2 domains of the large subunit rRNA gene showed that these novel species belong to the Wickerhamiella clade. The first was isolated from freshwater and a leaf of sugar cane (Saccharum officinarum) in Brazil and from leaves of Wedelia biflora in Taiwan. Described here as Wickerhamiella slavikovae sp. nov., it differs by 56 nucleotide substitutions and 19 gaps in the D1/D2 region of the large subunit rRNA gene from Candida sorbophila, the least divergent species. The second species, named Wickerhamiella goesii sp. nov., was isolated from leaves and the rhizosphere of sugar cane collected in Rio de Janeiro, Brazil. The species differs by 54 nucleotide substitutions and nine gaps in the D1/D2 domains from Candida drosophilae, its least divergent relative. The type strains are Wickerhamiella slavikovae sp. nov. IMUFRJ 52096(T) (= CBS 12417(T) = DBVPG 8032(T)) and Wickerhamiella goesii sp. nov. IMUFRJ 52102(T) (= CBS 12419(T) = DBVPG 8034(T)).

Unraveling the decolourizing ability of yeast isolates from dye-polluted and virgin environments: an ecological and taxonomical overview

Microcosm assays with dye-amended culture media under a shot-feeding strategy allowed us to obtain 100 yeast isolates from the wastewater outfall channel of a dyeing textile factory in Tucumán (Argentina). Meanwhile, 63 yeast isolates were obtained from Phoebe porphyria (Laurel del monte) samples collected from Las Yungas rainforest (Tucumán), via a classical isolation scheme. Isolated yeasts, both from dye-polluted and virgin environments, were compared for their textile dye decolourization ability when cultured on solid and liquid media. Nine isolates from wastewater and 17 from Las Yungas showed the highest decolourization potential on agar plates containing six different reactive dyes, either alone or as a mixture. Five yeasts from each environment were further selected on the basis of their high dye removal rate in Vilmafix(®) Red 7B-HE- or Vilmafix(®) Blue RR-BB-amended liquid cultures. Yeasts from wastewater showed slightly higher decolourization percentages after 36 h of culture than yeasts from Las Yungas (98-100% vs. 91-95%, respectively). However, isolates from Las Yungas exhibited higher specific decolourization rates than isolates from effluents (1.8-3.0 vs. 0.9-1.3 mg g(-1)h(-1), respectively). All selected isolates were first grouped according to microsatellite-PCR analysis and representative isolates from each group were subsequently identified based on the 26S rRNA gene sequence analysis. Yeasts from wastewater were identified as the ascomycetous Pichia kudriavzevii (100%) and closely related to Candida sorbophila (99.8%), whilst yeasts from Las Yungas were identified as the basidiomycetous Trichosporon akiyoshidainum and Trichosporon multisporum. It is suggested that findings concerning yeast selection during screening programs for dye-decolourizing yeasts may be explained in the light of the copiotroph-oligotroph microorganisms rationale.

Biotechnology for the production of essential oils, flavours and volatile isolates. A review.

AbstractVarious applications of biotechnological methods for the production of volatile compounds useful to the food and pharmaceutical industries are discussed. The yields obtained from intact or genetically modified plants are compared to those achieved by microbial methods. Plant yields are too low for the products to compete commercially to those synthesized chemically. Still lower yields are obtained with in vitro‐cultured plant tissues. Trangenic plants with altered methylerythritol path gave 50% more essential oil in the best case. The 100‐fold increases in shikimate‐derived volatiles, obtained with overexpressed alcohol dehydrogenase and five‐fold more C6 volatle aldehydes and 2‐phenylethanol, were produced with overexpressed lipoxygenase and 2‐phenylethanol dehydrogenase, respectively. However, the most spectacular yields were observed with biotransformations catalysed by microorganisms. Kluyveromyces marxianus, produces over 26 g/l 2‐phenylethanol from phenyalanine, whereas Candida sorbophila, Mucor circillenoides or Yarrowia lipolytica can produce 5–40 g/l γ‐decalactone from ricinoleic acid. Vanillin production from ferulic acid is in the range 12–60 g/l with Amycolatopsis and Streptomyces species. Vanillin can be produced at 5 g/l by Escherichia coli and amorphadiene yields of 37 g/l have been observed with Saccharomyces cerevisiae, both with the genetically overexpressed methyl–erythritol path. Genetically engineered β‐oxidation genes result in yields of 10 g/l γ‐decalactone by Yarrowia lipolytica and up to 80 g/l dicaboxylic acids by various yeasts. These results far exceed the theoretical limit of about 1 g/l required for consideration of a procedure as a commercially interesting process, alternative to chemical sythesis. Copyright © 2010 John Wiley & Sons, Ltd.

Influence of diseases on the wild eel stock: The case of Albufera Lake

In recent years, eel stocks in the European Union have declined dramatically. This decline has been attributed to habitat loss, over fishing, and more recently, pathogens, but little data exist on bacterial diseases of wild eels. This study reports on the bacterial and parasitic diseases affecting the wild-eel population of the Albufera Lake. Over a 3-year period, 122 eels were analysed after having been randomly chosen from those caught in the lagoon via traditional fishing procedures. This collection of individuals comprised eels at different growth stages as well as some individuals showing pathological signs, such as haemorrhagic fins, petechiae on the belly and ulcers. Microbial isolation was performed by culturing ulcers, kidney and liver samples on TSA agar plates. Isolates were identified and their virulence assessed, with results showing that the microbial diseases affecting the wild-eel population were: vibriosis [non-motile Vibrio vulnificus biotype 2 serovar A; LD 50 inferior to 3.6 × 10 3 cfu/fish], edwardsiellosis [ Edwardsiella tarda; LD 50; 1.5 × 10 4 to 7.4 × 10 5 cfu/fish], aeromonosis [ Aeromonas hydrophila, Aeromonas bestiarum and Aeromonas jandaei; LD 50 3.3 × 10 6 to 2.3 × 10 7 cfu/fish], and candidiasis [ Candida sorbophila; LD 50 4.6 × 10 6 to 3.7 × 10 7 cfu/fish], with an overall prevalence of 34.4%. Chronic bacterial infections presented an overall prevalence of 18.9%; mainly caused by mesophilic Aeromonas, producing tail-rot ulcers, and avirulent bacteria isolated from internal organs [ Pseudomonas/Alcaligenes, Plesiomonas shigelloides; LD 50 > 10 8 cfu/fish]. Swim-bladder nematode parasites [ Anguillicola crassus] were also collected from most of these individuals. Thus, prevalence of anguillicolosis was 11.5% in the wild-eel population, but increased to 20% among individuals affected by a chronic bacterial disease. The incidence of each pathology differed among individuals depending on their size [Pearson χ 2 (12 d.f.) = 23.772; p = 0.013]. The results of our study highlight three facts: 1) pathogenic bacteria could play a leading role in the decline of the eel population in the Albufera Lake; 2) the youngest eels may be the most susceptible to acute bacterial diseases in this natural habitat; and 3) elderly eels suffer from chronic illness, which may reduce the survival of these breeding individuals during their downstream migration to the sea.

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

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.

Candida sergipensis, a new asexual yeast species isolated from frozen pulps of tropical fruits.

Sixteen strains of the new yeast species Candida sergipensis have been isolated from frozen pulps of the tropical fruits umbú ( Spondias tuberosa Avr. Cam.) and mangaba ( Hancornia speciosa Gom.). Candida sergipensis was one of the prevalent species in the yeast community of these substrates. The new asexual ascomycetous yeast is phylogenetically related to Candida spandovensis and Candida sorbophila, species belonging to the Wickerhamiella clade, as evidenced by the sequences of the D1/D2 domains of their large subunit ribosomal DNAs. The species C. sergipensis and C. spandovensis can be separated on the basis of growth on 50% glucose agar, xylose and succinate, negative for the first species and positive for the second. The type culture is strain UFMG-R188 (CBS 9567).

Environmental adaptation factors of two yeasts isolated from the leachate of a uranium mineral heap.

Two yeasts from the effluent of a uranium mineral heap were identified as Candida sorbophila and Rhodotorula mucilaginosa. They are well adapted to such an environment as shown by their tolerance to metals and acid pH. However, different mechanisms could be involved in the adaptation: C. sorbophila could be considered to be more acid-tolerant as a function of its specific growth rate and respiratory behavior at acidic pH in an organic medium. However, R. mucilaginosa was capable of growing by 1 log unit when inoculated in a sterilized leaching effluent or in a ferrous mineral medium, without added organic compounds. Indeed, the ability of R. mucilaginosa to grow in a low-nutrient environment could be as important a factor as its acid tolerance for coping in the isolation habitat. In mixed cultures with sulfide-oxidizing bacteria, no effect was observed on the ferrous oxidation normally carried out by these bacteria. However, a negative effect on both yeasts, especially in C. sorbophila, was observed, when the bacteria were present.

Environmental adaptation factors of two yeasts isolated from the leachate of a uranium mineral heap

Two yeasts from the effluent of a uranium mineral heap were identified as Candida sorbophila and Rhodotorula mucilaginosa. They are well adapted to such an environment as shown by their tolerance to metals and acid pH. However, different mechanisms could be involved in the adaptation: C. sorbophila could be considered to be more acid-tolerant as a function of its specific growth rate and respiratory behavior at acidic pH in an organic medium. However, R. mucilaginosa was capable of growing by 1 log unit when inoculated in a sterilized leaching effluent or in a ferrous mineral medium, without added organic compounds. Indeed, the ability of R. mucilaginosa to grow in a low-nutrient environment could be as important a factor as its acid tolerance for coping in the isolation habitat. In mixed cultures with sulfide-oxidizing bacteria, no effect was observed on the ferrous oxidation normally carried out by these bacteria. However, a negative effect on both yeasts, especially in C. sorbophila, was observed, when the bacteria were present.

Asymmetric bioreductions: application to the synthesis of pharmaceuticals

Selected examples of asymmetric bioreductions of pharmaceutically relevant prochiral ketones are reviewed. These data show that microbial screens lead to the identification of appropriate biocatalysts, and that the use of miniaturized and semi-automated technology can greatly reduce both labor and lead times. The same data also highlight the need to evaluate a relatively large and/or diverse microbial population (highlighting biodiversity). We also found that in many instances the luxury of producing either enantiomers with high optical purity, enantiocomplementarity, can be achieved when employing different microbial strains. Process development studies reviewed here demonstrate that it is possible in some cases to understand and control the production of an unwanted enantiomer or by-product. Finally, a specific example, the asymmetric bioreduction of a ketone by Candida sorbophila, shows that process development studies which optimized, the bioreduction environmental conditions (pH, temperature…), the addition of ketone, and the implementation of a nutrient feeding strategy in conjunction with the use of a defined cultivation medium were key in achieving increased bioreduction rates and product titers. When scaled-up in pilot plant bioreactors, the bioreduction process supported the production of several kilograms of (R)-alcohol (enantiomeric excess (e.e.)>98%), with an isolated product yield of about 80%.

Asymmetric bioreduction of (2-(4-nitro-phenyl) -N-(2-oxo-2-pyridin-3-yl-ethyl)-acetamide) to its corresponding (R) alcohol [( R) -N- (2-hydroxy-2-pyridin-3-yl-ethyl)-2-(4-nitro-phenyl)-acetamide] by using Candida sorbophila MY 1833

A microbial screen identified the yeast Candida sorbophila MY 1833 as a suitable biocatalyst for the asymmetric bioreduction of a ketone (2-(4-nitro-phenyl) -N-(2-oxo-2-pyridin-3-yl-ethyl)-acetamide) to its corresponding (R) alcohol [( R) -N-(2-hydroxy-2-pyridin-3-yl-ethyl)-2-(4-nitro-phenyl)-acetamide]. Studies yielded the formulation of a chemically defined cultivation medium that supported excellent growth and bioconversion activity. Process development showed that the optimization of the bioreduction environmental conditions (pH, temperature), the timing of ketone addition, and the implementation of a nutrient feeding strategy were key factors in achieving increased bioreduction rates. The optimized process achieved a 10-fold bioreduction rate improvement over the original process, while reaching final product concentrations of up to 60 g/l. When scaled up in Pilot Plant bioreactors (280 l), the bioreduction process supported the production of several kilograms of highly optically pure (R) alcohol (enantiomeric excess > 98%).