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Cureus Feb 2024We report the case of an 84-year-old man with a history of IgG4-related sclerosing cholangitis who was diagnosed with advanced esophageal cancer and underwent radiation...
We report the case of an 84-year-old man with a history of IgG4-related sclerosing cholangitis who was diagnosed with advanced esophageal cancer and underwent radiation and chemotherapy. An implantable central venous access port was placed for chemotherapy and total parenteral nutrition. The patient presented with a fever and received antimicrobial therapy for acute cholangitis but remained febrile, and subsequently, yeast was detected in the aerobic bottle of blood culture obtained from the central venous line. The yeast was identified as . Liposomal amphotericin B was administered, and the central line access port was removed. After confirmation of negative blood cultures and 14 days post treatment, he underwent reinsertion of the central line access port. Due to persistent pain at the insertion site, fluconazole was added for an additional 14 days, and the patient was discharged and transferred to another hospital. is a rare fungal infection with other synonyms including , , and . A literature review of 53 case reports of , , , and was conducted, with a total of 211 cases reviewed. Fungemia was reported in 94% of cases, with central venous catheterization, parental feeding, low birth weight, and immunocompromised status identified as major risk factors. The majority of cases were pediatric, particularly neonatal, and there were reports of nosocomial infections causing outbreaks, with some cases involving the eye such as endophthalmitis or keratitis.
PubMed: 38445156
DOI: 10.7759/cureus.53550 -
Microbial Cell Factories Sep 2015The product yield and titers of biological processes involving the conversion of biomass to desirable chemicals can be limited by environmental stresses encountered by...
BACKGROUND
The product yield and titers of biological processes involving the conversion of biomass to desirable chemicals can be limited by environmental stresses encountered by the microbial hosts used for the bioconversion. One of these main stresses is growth inhibition due to exposure to low pH conditions. In order to circumvent this problem, understanding the biological mechanisms involved in acid stress response and tolerance is essential. Characterisation of wild yeasts that have a natural ability to resist such harsh conditions will pave the way to understand the biological basis underlying acid stress resistance. Pichia anomala possesses a unique ability to adapt to and tolerate a number of environmental stresses particularly low pH stress giving it the advantage to outcompete other microorganisms under such conditions. However, the genetic basis of this resistance has not been previously studied.
RESULTS
To this end, we isolated an acid resistant strain of P. anomala, performed a gross phenotypic characterisation at low pH and also performed a whole genome and total RNA sequencing. By integrating the RNA-seq data with the genome sequencing data, we found that several genes associated with different biological processes including proton efflux, the electron transfer chain and oxidative phosphorylation were highly expressed in P. anomala cells grown in low pH media. We therefore present data supporting the notion that a high expression of proton pumps in the plasma membrane coupled with an increase in mitochondrial ATP production enables the high level of acid stress tolerance of P. anomala.
CONCLUSIONS
Our findings provide insight into the molecular and genetic basis of low pH tolerance in P. anomala which was previously unknown. Ultimately, this is a step towards developing non-conventional yeasts such as P. anomala for the production of industrially relevant chemicals under low pH conditions.
Topics: Adenosine Triphosphate; Amino Acid Sequence; Biomass; Electron Transport; Fungal Proteins; Genome, Fungal; Hydrogen-Ion Concentration; Mitochondria; Models, Molecular; Molecular Sequence Data; Oxidative Phosphorylation; Pichia; Sequence Alignment; Sequence Analysis, RNA; Stress, Physiological; Transcriptome
PubMed: 26376644
DOI: 10.1186/s12934-015-0331-4 -
Foods (Basel, Switzerland) Oct 2023Currently, non- yeasts are the subject of interest, among other things, for their contribution to the aromatic complexity of wines. In this study, the characterisation...
Currently, non- yeasts are the subject of interest, among other things, for their contribution to the aromatic complexity of wines. In this study, the characterisation of non- yeasts was addressed by their isolation during spontaneous fermentations of organic Verdejo grapes, obtaining a total of 484 isolates, of which 11% were identified by molecular techniques as non- yeasts. Fermentative isolates belonging to the species , , , , , and were analysed. Significant differences were found in the yeast populations established at the different fermentation stages. Interestingly, stood up as a widely distributed species in vineyards, vintages, and fermentation stages. Several of the strains studied stood out for their biotechnological potential in the production of Verdejo wine, showing the presence of relevant enzymatic activity for the release of varietal aromas and the technological improvement of the winemaking process. Three enzymatic activities were found in an important number of isolates, β-glucosidase, protease, and β-lyase, implicated in the positive aromatic impact on this style of white wine. In that sense, all the isolates of presented those activities. isolates were highlighted for their significant β-lyase activity. In addition, was outlined because of its potential to achieve an elevated fermenting power, as well as the lack of lag phase. The results obtained highlight the importance of maintaining the microbial diversity that contributes to the production of wines with unique and distinctive characteristics of the production region.
PubMed: 37835297
DOI: 10.3390/foods12193644 -
Journal of Fungi (Basel, Switzerland) Jan 2022This study investigated the fermentation performances and aroma compositions of synthetic grape juice that was fermented by four indigenous non- yeast isolates that were...
Evaluation of Four Indigenous Non- Yeasts Isolated from the Shangri-La Wine Region (China) for Their Fermentation Performances and Aroma Compositions in Synthetic Grape Juice Fermentation.
This study investigated the fermentation performances and aroma compositions of synthetic grape juice that was fermented by four indigenous non- yeast isolates that were obtained from the Shangri-La wine region (China): (AD-58), (BZL-28), (BZL-11), and (DR-110), in comparison to those of (EC1118). The four indigenous non- yeasts showed a lower fermentative capacity and a lower conversion rate of sugar to alcohol, but a higher yield of volatile acidity. (DR-110) had a greater ability to produce numerous esters and short-chain fatty acids and the representative flavors of its fermented medium were fruity and fatty. (BZL-28), interestingly, exhibited great capacity in the formation of many monoterpenes, particularly ()-β-ocimene, -β-ocimene, linalool, citral, and geraniol and its fermented medium was characterized by a strong fruity (citrus-like) and floral flavor. (AD-58) and (BZL-11) only mildly affected the aroma profiles of their resultant fermented media, since the concentrations of most of the volatiles that were produced by these two isolates were much lower than their sensory thresholds. The four indigenous non- yeasts exhibited distinctive fermentation performances and aroma production behaviors. In particularly, (DR-110) and (BZL-28) have shown good potential in enhancing the aromas and complexity of wine.
PubMed: 35205900
DOI: 10.3390/jof8020146 -
World Journal of Microbiology &... Nov 2022Yeast mannoproteins are proposed as a paraprobiotics with antimicrobial and prebiotic properties. They can be used as biopreservatives in food and in diseases therapies....
Yeast mannoproteins are proposed as a paraprobiotics with antimicrobial and prebiotic properties. They can be used as biopreservatives in food and in diseases therapies. The knowledge about the specificity and/or capability of their influence on the growth of different microorganism is limited. The study determined the effect of mannoprotein preparations of Saccharomyces cerevisiae (S. cerevisiae) ATCC 7090 and nonconventional yeast origin [Metschnikowia reukaufii (M. reukaufii) WLP 4650 and Wickerhamomyces anomalus (W. anomalus) CCY 38-1-13] on the growth of selected bacteria of the genera: Lactobacilllus, Limosilatobacillus, Limosilatobacillus, Bifidobacterium, Staphylococcus, Enterococcus, Pseudomonas, Escherichia, Proteus and Salmonella. The degree of stimulation or growth inhibition of tested bacteria depended on the type and dose of the mannoprotein and the bacterial strain. The addition of the tested preparations in the entire range of applied concentrations had a positive effect especially on the growth of Lactobacillus arabinosus ATCC 8014 and Bifidobacterium animalis subsp. lactis B12. Mannoproteins isolated from S. cerevisiae limited the growth of the Escherichia coli (E. coli) ATCC 25922, Pseudomonas aureoginosa (P. aureoginosa) ATCC 27853, Proteus mirabilis ATCC 35659 and Salmonella Enteritidis ATCC 13076 to the greatest extent, while preparations of M. reukaufii and W. anomalus origin most effectively limited the growth of Staphylococcus aureus strains, E. coli and P. aureoginosa. The growth of Enterococcus faecalis was stimulated by the presence of all studied preparations in most of the concentrations used. Further research will determine how the purification process of studied mannoproteins or oligosaccharide fractions, its structure and composition influence on the growth of selected bacteria and what is the mechanism of its activity.
Topics: Saccharomyces cerevisiae; Escherichia coli; Phylogeny; Anti-Infective Agents; Anti-Bacterial Agents; Bacteria; Microbial Sensitivity Tests
PubMed: 36319710
DOI: 10.1007/s11274-022-03448-5 -
Brazilian Journal of Microbiology :... Jun 2021Lignocellulosic hydrolysates will also contain compounds that inhibit microbial metabolism, such as organic acids, furaldehydes, and phenolic compounds. Understanding... (Comparative Study)
Comparative Study
Lignocellulosic hydrolysates will also contain compounds that inhibit microbial metabolism, such as organic acids, furaldehydes, and phenolic compounds. Understanding the response of yeasts toward such inhibitors is important to the development of different bioprocesses. In this work, the growth capacity of 7 industrial Saccharomyces cerevisiae and 7 non-Saccharomyces yeasts was compared in the presence of 3 different concentrations of furaldehydes (furfural and 5-hydroxymetil-furfural), organic acids (acetic and formic acids), and phenolic compounds (vanillin, syringaldehyde, ferulic, and coumaric acids). Then, Candida tropicalis JA2, Meyerozyma caribbica JA9, Wickerhamomyces anomalus 740, S. cerevisiae JP1, B1.1, and G06 were selected for fermentation in presence of acetic acid, HMF, and vanillin because they proved to be most tolerant to the tested compounds, while Spathaspora sp. JA1 because its xylose consumption rate. The results obtained showed a dose-dependent response of the yeasts toward the eight different inhibitors. Among the compared yeasts, S. cerevisiae strains presented higher tolerance than non-Saccharomyces, 3 of them with the highest tolerance among all. Regarding the non-Saccharomyces yeasts, C. tropicalis JA2 and W. anomalus 740 appeared as the most tolerant, whereas Spathaspora strains appeared very sensitive to the different compounds.
Topics: Acids; Furaldehyde; Lignin; Microbial Viability; Phenols; Saccharomyces cerevisiae; Yeasts
PubMed: 33825150
DOI: 10.1007/s42770-021-00489-0 -
Foods (Basel, Switzerland) Aug 2020The influence of fruit varieties on yeast ecology during spontaneous plum mash fermentation was investigated. Yeast colonies were isolated from mashes obtained from four...
The influence of fruit varieties on yeast ecology during spontaneous plum mash fermentation was investigated. Yeast colonies were isolated from mashes obtained from four plum varieties throughout fermentation in laboratory conditions during two consecutive years. The yeast strains were differentiated by random amplification of polymorphic DNA (RAPD-PCR) and identified by the 26S rDNA D1/D2 sequence analysis. , spp. and were the dominant yeasts during the early stages of plum mash fermentation, while the middle and end phases were dominated by . The strains of , , , and were also detected in fermenting plum mashes. sp. M1, H1 and H2 strains were detected in all samples, irrespective of the tested variety and year. Investigation of the impact of individual yeast strains on the production of volatile compounds showed the potential possibility of using them as starter cultures.
PubMed: 32759797
DOI: 10.3390/foods9081054 -
Frontiers in Physiology 2022Management of the rice brown planthopper Stål is challenging because it can rapidly adapt to new pesticides within several generations. Combined use of chemical...
Management of the rice brown planthopper Stål is challenging because it can rapidly adapt to new pesticides within several generations. Combined use of chemical insecticides and antimicrobials was proposed as an alternative strategy to control . Our previous experiments identified two effective agents (chemical insecticide: pymetrozine and antimicrobial: zhongshengmycin) that act on different targets in . However, conditions and effectiveness of combinations of antimicrobials and insecticides against are still unknown. Here, we evaluated separate and combined effects of pymetrozine and zhongshengmycin on third instar nymphs of under laboratory and greenhouse conditions. Results showed that zhongshengmycin exerts significant inhibitory effects on the three endosymbionts , , and cultured of . Combinations of pymetrozine and zhongshengmycin under laboratory conditions produced additive or synergistic effects on and caused higher mortality in third instar nymphs than either of them used alone. Experiments under greenhouse conditions further demonstrated that effective component quality ratio of pymetrozine to zhongshengmycin of 1:10 and 1:40 with co-toxicity coefficients of 221.63 and 672.87, respectively, also produced significant synergistic effects against . Our results indicated that chemical insecticides combined with antimicrobials may provide a potential novel strategy for controlling by inhibiting its endosymbionts.
PubMed: 35707007
DOI: 10.3389/fphys.2022.875610 -
Food Microbiology Aug 2023Contamination of white-brined cheeses (WBCs) with yeasts is of major concern in the dairy industry. This study aimed to identify yeast contaminants and characterize...
Contamination of white-brined cheeses (WBCs) with yeasts is of major concern in the dairy industry. This study aimed to identify yeast contaminants and characterize their succession in white-brined cheese during a shelf-life of 52 weeks. White-brined cheeses added herbs (WBC1) or sundried tomatoes (WBC2) were produced at a Danish dairy and incubated at 5 °C and 10 °C. An increase in yeast counts was observed for both products within the first 12-14 weeks of incubation and stabilized afterwards varying in a range of 4.19-7.08 log CFU/g. Interestingly, higher incubation temperature, especially in WBC2, led to lower yeast counts, concurrently with higher diversity of yeast species. Observed decrease in yeast counts was, most likely, due to negative interactions between yeast species leading to growth inhibition. In total, 469 yeast isolates from WBC1 and WBC2 were genotypically classified using the (GTG)-rep-PCR technique. Out of them, 132 representative isolates were further identified by sequencing the D1/D2 domain of the 26 S rRNA gene. Predominant yeast species in WBCs were Candida zeylanoides and Debaryomyces hansenii, while Candida parapsilosis, Kazachstania bulderi, Kluyveromyces lactis, Pichia fermentans, Pichia kudriavzevii, Rhodotorula mucilaginosa, Torulaspora delbrueckii, and Wickerhamomyces anomalus were found in lower frequency. Heterogeneity of yeast species in WBC2 was generally larger compared to WBC1. This study indicated that, along with contamination levels, taxonomic heterogeneity of yeasts is an important factor influencing yeast cell counts, as well as product quality during storage.
Topics: Cheese; Yeasts; Polymerase Chain Reaction
PubMed: 37098422
DOI: 10.1016/j.fm.2023.104266 -
Medical Mycology Oct 2019Although Cyberlindnera fabinaii is a rare opportunist yeast species, its ability to cause septicemia, produce biofilm, and rapid acquisition of resistance to fluconazole... (Review)
Review
Unequivocal identification of an underestimated opportunistic yeast species, Cyberlindnera fabianii, and its close relatives using a dual-function PCR and literature review of published cases.
Although Cyberlindnera fabinaii is a rare opportunist yeast species, its ability to cause septicemia, produce biofilm, and rapid acquisition of resistance to fluconazole and voriconazole, reinforced the urge for its identification from its closely related species. Widely used biochemical assays mainly identify Cyberlindnera fabinaii as Cyberlindnera jadinii and Wickerhamomyces anomalus, resulting in underestimation of this yeast in clinical settings. Moreover, the urge for a reliable molecular means of identification remains unsolved for 28 years. In order to unequivocally differentiate Cy. fabianii, Cy. mississipiensis, Cy. jadinii, and W. anomalus, we designed a dual-function multiplex polymerase chain reaction (PCR) assay. Challenging our dual-function multiplex PCR assay with 30 most clinically important yeast species, proved its specificity. Although conventional PCR could differentiate four target species, the real-time PCR counterpart due to Tm overlap misidentified Cy. mississipiensis as Cy. jadinii. Alongside of presenting a comprehensive literature review of published cases of Cy. fabianii from 1990 to 2018, we collected various clinical isolates from Tehran, Shiraz, and Fasa (July 1, 2017, to December 31, 2017) to find a passive relative distribution of these closely-related species in Iran. Subjecting our Iranian collection of yeast isolates to matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) MS and LSU and ITS rDNA sequencing revealed six isolates of Cy. fabianii (central venous catheter n = 2 and vaginal swabs n = 4) and one isolate of Cy. jadinii (vaginal swabs). Due to the use of biochemical assays in global ARTEMIS study, we encourage reidentification of clinical isolates of Cy. jadinii and Cy. jadinii using MALDI-TOF or Sanger sequencing that might lead to correcting the distribution of this fungus.
Topics: Antifungal Agents; DNA Primers; DNA, Ribosomal; Female; Humans; Iran; Male; Multiplex Polymerase Chain Reaction; Mycoses; Saccharomycetales; Sensitivity and Specificity; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; Vagina
PubMed: 30649481
DOI: 10.1093/mmy/myy148