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Background and Aims: Fungicides used against the mould Botrytis cinerea can also non‐specifically affect indigenous yeasts important for the development of complex wine aroma. Our aim was to determine the minimal inhibitory concentration of the fungicides iprodione, pyrimethanil and fludioxonil plus cyprodinil for 109 yeasts of the grape berry microbiota. Methods and Results: We measured the respiration activity of yeasts, changes in growth kinetics and adenosine triphosphate production. Fungicide tolerance may be a conserved feature within the yeast's genera, however, some heterogeneity between isolates remains. The viability and growth of 15 beneficial isolates were inhibited by fungicides at a residue concentration below the maximum permitted residue limits. These isolates belonged to the yeast species: Metschnikowia pulcherrima, Pichia kluyveri, Hanseniaspora uvarum and Bulleromyces albus. Furthermore, isolates of typical spoilage yeasts, such as Dekkera bruxellensis, Meyerozyma guilliermondii and Pichia membranifaciens, were found to be tolerant of a concentration of fungicides greater than that recommended for application by the suppliers. Conclusions: Fungicide residues hindered the viability of desirable isolates and promoted the growth of several spoilage isolates and thus may have a negative impact on wine aroma. Significance of the Study: For spontaneous fermentations the application of fungicides in the vineyard could add to the seasonal fluctuations of aroma and to the development of off‐flavours. [ABSTRACT FROM AUTHOR]

Summary: Campylobacter jejuni is among the most prevalent causes of human bacterial gastroenteritis worldwide. Domesticated animals and, especially, chicken meat are considered to be the main sources of infections. However, the contribution of surface waters and wildlife in C. jejuni transmission to humans is not well understood. We have evaluated the source attribution potential of a six‐gene multiplex PCR (mPCR) method coupled with STRUCTURE analysis on a set of 410 C. jejuni strains isolated from environment, livestock, food and humans in central Europe. Multiplex PCR fingerprints were analysed using Subclade prediction algorithm to classify them into six distinct mPCR clades. A subset of C. jejuni isolates (70%) was characterized by multilocus sequence typing (MLST) demonstrating 74% congruence between mPCR and MLST. The correspondence analysis of mPCR clades and sources of isolation indicated three distinct groups in the studied C. jejuni population—the first one associated with isolates from poultry, the second one with isolates from cattle, and the third one with isolates from the environment. The STRUCTURE analysis attributed 7.2% and 21.7% of human isolates to environmental sources based on MLST and mPCR fingerprints, respectively. [ABSTRACT FROM AUTHOR]

Impact of three fungicides against B. cinerea (iprodione, pyrimethanil and f ludioxonil plus cyprodinil) on the population of Saccharomyces cerevisiae strains during the spontaneous alcoholic fermentation was studied. With regard to the use of fungicides in the vineyard at two stages of the grapevine growth we followed four different spontaneous fermentations: control, iprodione, pyrimethanil and f ludioxonil plus cyprodinil. The fungicide residues in the grapes were determined by GC/MS system and the fermentations were followed by changes in yeast, sugar, and ethanol concentrations using colony counting and HPLC. The karyotype analysis of 473 isolates was done by pulsed-field gel electrophoresis. The fungicide residues in the grapes at the harvest were below the maximum residue limits. Isolates of S. cerevisiae were classified into 15 karyotype groups. The duration of the processes and the populations of the karyotypes differed between the fermentations. The iprodione and control fermentations lasted 36 days with the prevalence of karyotype A while the fludioxonil plus cyprodinil fermentation lasted 50 days and karyotype D led the process. In the pyrimethanil fermentation, none of the karyotypes prevailed in the must and the fermentation lasted much longer than others did (68 days). The results showed that the fungicide residues have an influence on the fermentation kinetics and selection of S. cerevisiae strains during the spontaneous alcoholic fermentation and therefore should be considered as an important factor that may indirectly influence the formation of fermentation aroma in the wine produced by such process.

Microbial biodiversity can also be reflected in final product composition. The work described in this paper investigates the differences in the amino acid composition of 14 Malvasia musts/wines fermented with local and commercial starter yeasts, comparing all to the spontaneous fermentations of must of the same origin. We tried to ascertain whether the changes were dependent upon different initiations of fermentations. A comparative study of free and total amino acid evolution was prepared. The total concentration of 15 amino acids studied was 1975 mg/l, and the concentration of fraee amino acids was 1061 mg/l. Spontaneous and induced fermentations showed different fermentation rates. Three to nine days were needed to reduce sugar by 50%. Although the proline is regarded as non-assailable amino acid, decreases in concentration were observed. Lysine was the only amino acid where the concentration increased. The minimal uptakes of amino acids occurred during spontaneous fermentations, whereas the maximal uptakes were observed in the fermentations inoculated with local starters.

The global diversity of fungi has been estimated between 2 to 11 million species, of which only about 155 000 have been named. Most fungi are invisible to the unaided eye, but they represent a major component of biodiversity on our planet, and play essential ecological roles, supporting life as we know it. Although approximately 20 000 fungal genera are presently recognised, the ecology of most remains undetermined. Despite all this diversity, the mycological community actively researches some fungal genera more commonly than others. This poses an interesting question: why have some fungal genera impacted mycology and related fields more than others? To address this issue, we conducted a bibliometric analysis to identify the top 100 most cited fungal genera. A thorough database search of the Web of Science, Google Scholar, and PubMed was performed to establish which genera are most cited. The most cited 10 genera are Saccharomyces , Candida , Aspergillus , Fusarium , Penicillium , Trichoderma , Botrytis , Pichia , Cryptococcus and Alternaria . Case studies are presented for the 100 most cited genera with general background, notes on their ecology and economic significance and important research advances. This paper provides a historic overview of scientific research of these genera and the prospect for further research. Citation: Bhunjun CS, Chen YJ, Phukhamsakda C, Boekhout T, Groenewald JZ, McKenzie EHC, Francisco EC, Frisvad JC, Groenewald M, Hurdeal VG, Luangsa-ard J, Perrone G, Visagie CM, Bai FY, Błaszkowski J, Braun U, de Souza FA, de Queiroz MB, Dutta AK, Gonkhom D, Goto BT, Guarnaccia V, Hagen F, Houbraken J, Lachance MA, Li JJ, Luo KY, Magurno F, Mongkolsamrit S, Robert V, Roy N, Tibpromma S, Wanasinghe DN, Wang DQ, Wei DP, Zhao CL, Aiphuk W, Ajayi-Oyetunde O, Arantes TD, Araujo JC, Begerow D, Bakhshi M, Barbosa RN, Behrens FH, Bensch K, Bezerra JDP, Bilański P, Bradley CA, Bubner B, Burgess TI, Buyck B, Čadež N, Cai L, Calaça FJS, Campbell LJ, Chaverri P, Chen YY, Chethana KWT, Coetzee B, Costa MM, Chen Q, Custódio FA, Dai YC, Damm U, de Azevedo Santiago ALCM, De Miccolis Angelini RM, Dijksterhuis J, Dissanayake AJ, Doilom M, Dong W, Alvarez-Duarte E, Fischer M, Gajanayake AJ, Gené J, Gomdola D, Gomes AAM, Hausner G, He MQ, Hou L, Iturrieta-González I, Jami F, Jankowiak R, Jayawardena RS, Kandemir H, Kiss L, Kobmoo N, Kowalski T, Landi L, Lin CG, Liu JK, Liu XB, Loizides M, Luangharn T, Maharachchikumbura SSN, Makhathini Mkhwanazi GJ, Manawasinghe IS, Marin-Felix Y, McTaggart AR, Moreau PA, Morozova OV, Mostert L, Osiewacz HD, Pem D, Phookamsak R, Pollastro S, Pordel A, Poyntner C, Phillips AJL, Phonemany M, Promputtha I, Rathnayaka AR, Rodrigues AM, Romanazzi G, Rothmann L, Salgado-Salazar C, Sandoval-Denis M, Saupe SJ, Scholler M, Scott P, Shivas RG, Silar P, Souza-Motta CM, Silva-Filho AGS, Spies CFJ, Stchigel AM, Sterflinger K, Summerbell RC, Svetasheva TY, Takamatsu S, Theelen B, Theodoro RC, Thines M, Thongklang N, Torres R, Turchetti B, van den Brule T, Wang XW, Wartchow F, Welti S, Wijesinghe SN, Wu F, Xu R, Yang ZL, Yilmaz N, Yurkov A, Zhao L, Zhao RL, Zhou N, Hyde KD, Crous PW (2024). What are the 100 most cited fungal genera? Studies in Mycology 108 : 1-411. doi: 10.3114/sim.2024.108.01., Competing Interests: The authors declare that there is no conflict of interest., (© 2024 Westerdijk Fungal Biodiversity Institute.)

Converting waste into high-value products promotes sustainability by reducing waste and creating new revenue streams. This study investigates the potential of diverse yeasts for microbial oil production by utilizing short-chain fatty acids (SCFAs) that can be produced from organic waste and focuses on identifying strains with the best SCFA utilisation, tolerance and lipid production. A collection of 1434 yeast strains was cultivated with SCFAs as the sole carbon source. Eleven strains emerged as candidates with promising growth rates and high lipid accumulation. Subsequent fermentation experiments in liquid SCFA-rich media, which focused on optimizing lipid accumulation by adjusting the carbon to nitrogen (C/N) ratio, showed an increase in lipid content at a C/N ratio of 200:1, but with a concurrent reduction in biomass. Two strains were characterized by their superior ability to produce lipids compared to the reference strain Yarrowia lipolytica CECT124: Y. lipolytica EXF-17398 and Pichia manshurica EXF-7849. Characterization of these two strains indicated that they exhibit a biotechnologically relevant balance between maximizing lipid yield and maintaining growth at high SCFA concentrations. These results emphasize the potential of using SCFAs as a sustainable feedstock for oleochemical production, offering a dual benefit of waste valorisation and microbial oil production., (© 2024. The Author(s).)

During the course of independent studies in Europe, North America, and Africa, seven yeast strains were isolated from insect frass, decaying wood, tree flux, and olive oil sediment. Phylogenetic analysis of two barcoding DNA regions (internal transcribed spacer and the D1/D2 domain of the LSU rRNA gene) revealed that they belong to two closely related undescribed species distinct from all genera in the family Debaryomycetaceae. For reliable taxonomic placement the genomes of four strains of the two novel species and six type strains of closely related species were sequenced. Orthologous genes from 54 genomes of representatives of the Pichiomycetes and 23 outgroup taxa were concatenated to construct a fully supported phylogenetic tree. Consistent with the assumptions, we found that the two new species belong to a novel genus. In addition, the delimitation of the novel species was supported by genetic distance calculations from average nucleotide identity (ANI) and digital DNA:DNA hybridization (dDDH) values. The physiological characterization of the novel species was generally consistent with their genomic content. All strains had two alleles encoding secretory lipase in either two or three copies depending on the species. However, lipolytic activity was detected only in strains with three copies of the secretory lipase gene. Nevertheless, lipolytic activity might be related to their association with the insect gut. Based on these results, formal descriptions of the new genus Rasporella gen. nov. and of two new species Rasporella dianae sp. nov. (holotype UCDFST 68-643 T , MycoBank no.: 850238) and Rasporella oleae sp. nov. (holotype ZIM 2471 T , MycoBank no.: 850126) are provided., (© 2023 The Authors. Yeast published by John Wiley & Sons Ltd.)

Organisms exhibit extensive variation in ecological niche breadth, from very narrow (specialists) to very broad (generalists). Paradigms proposed to explain this variation either invoke trade-offs between performance efficiency and breadth or underlying intrinsic or extrinsic factors. We assembled genomic (1,154 yeast strains from 1,049 species), metabolic (quantitative measures of growth of 843 species in 24 conditions), and ecological (environmental ontology of 1,088 species) data from nearly all known species of the ancient fungal subphylum Saccharomycotina to examine niche breadth evolution. We found large interspecific differences in carbon breadth stem from intrinsic differences in genes encoding specific metabolic pathways but no evidence of trade-offs and a limited role of extrinsic ecological factors. These comprehensive data argue that intrinsic factors driving microbial niche breadth variation., Competing Interests: Competing interests: JLS is a scientific adviser for WittGen Biotechnologies and an adviser for ForensisGroup, Inc. AR is a scientific consultant for LifeMine Therapeutics, Inc. The other authors declare no other competing interests.

Clavispora santaluciae was recently described as a novel non- Saccharomyces yeast species, isolated from grapes of Azores vineyards, a Portuguese archipelago with particular environmental conditions, and from Italian grapes infected with Drosophila suzukii . In the present work, the genome of five Clavispora santaluciae strains was sequenced, assembled, and annotated for the first time, using robust pipelines, and a combination of both long- and short-read sequencing platforms. Genome comparisons revealed specific differences between strains of Clavispora santaluciae reflecting their isolation in two separate ecological niches-Azorean and Italian vineyards-as well as mechanisms of adaptation to the intricate and arduous environmental features of the geographical location from which they were isolated. In particular, relevant differences were detected in the number of coding genes (shared and unique) and transposable elements, the amount and diversity of non-coding RNAs, and the enzymatic potential of each strain through the analysis of their CAZyome. A comparative study was also conducted between the Clavispora santaluciae genome and those of the remaining species of the Metschnikowiaceae family. Our phylogenetic and genomic analysis, comprising 126 yeast strains (alignment of 2362 common proteins) allowed the establishment of a robust phylogram of Metschnikowiaceae and detailed incongruencies to be clarified in the future.

Yeasts are ubiquitous in temperate forests. While this broad habitat is well-defined, the yeasts inhabiting it and their life cycles, niches, and contributions to ecosystem functioning are less understood. Yeasts are present on nearly all sampled substrates in temperate forests worldwide. They associate with soils, macroorganisms, and other habitats and no doubt contribute to broader ecosystem-wide processes. Researchers have gathered information leading to hypotheses about yeasts' niches and their life cycles based on physiological observations in the laboratory as well as genomic analyses, but the challenge remains to test these hypotheses in the forests themselves. Here, we summarize the habitat and global patterns of yeast diversity, give some information on a handful of well-studied temperate forest yeast genera, discuss the various strategies to isolate forest yeasts, and explain temperate forest yeasts' contributions to biotechnology. We close with a summary of the many future directions and outstanding questions facing researchers in temperate forest yeast ecology. Yeasts present an exciting opportunity to better understand the hidden world of microbial ecology in this threatened and global habitat., (© 2022 John Wiley & Sons, Ltd.)

During a survey of Nothofagus trees and their parasitic fungi in Andean Patagonia (Argentina), genetically distinct strains of Hanseniaspora were obtained from the sugar-containing stromata of parasitic Cyttaria spp. Phylogenetic analyses based on the single-gene sequences (encoding rRNA and actin) or on conserved, single-copy, orthologous genes from genome sequence assemblies revealed that these strains represent a new species closely related to Hanseniaspora valbyensis. Additionally, delimitation of this novel species was supported by genetic distance calculations using overall genome relatedness indices (OGRI) between the novel taxon and its closest relatives. To better understand the mode of speciation in Hanseniaspora , we examined genes that were retained or lost in the novel species in comparison to its closest relatives. These analyses show that, during diversification, this novel species and its closest relatives, H. valbyensis and Hanseniaspora jakobsenii , lost mitochondrial and other genes involved in the generation of precursor metabolites and energy, which could explain their slower growth and higher ethanol yields under aerobic conditions. Similarly, Hanseniaspora mollemarum lost the ability to sporulate, along with genes that are involved in meiosis and mating. Based on these findings, a formal description of the novel yeast species Hanseniaspora smithiae sp. nov. is proposed, with CRUB 1602 H as the holotype., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Čadež, Bellora, Ulloa, Tome, Petković, Groenewald, Hittinger and Libkind.)

The unambiguous application of fungal names is important to communicate scientific findings. Names are critical for (clinical) diagnostics, legal compliance, and regulatory controls, such as biosafety, food security, quarantine regulations, and industrial applications. Consequently, the stability of the taxonomic system and the traceability of nomenclatural changes is crucial for a broad range of users and taxonomists. The unambiguous application of names is assured by the preservation of nomenclatural history and the physical organisms representing a name. Fungi are extremely diverse in terms of ecology, lifestyle, and methods of study. Predominantly unicellular fungi known as yeasts are usually investigated as living cultures. Methods to characterize yeasts include physiological (growth) tests and experiments to induce a sexual morph; both methods require viable cultures. Thus, the preservation and availability of viable reference cultures are important, and cultures representing reference material are cited in species descriptions. Historical surveys revealed drawbacks and inconsistencies between past practices and modern requirements as stated in the International Code of Nomenclature for Algae, Fungi, and Plants (ICNafp). Improper typification of yeasts is a common problem, resulting in a large number invalid yeast species names. With this opinion letter, we address the problem that culturable microorganisms, notably some fungi and algae, require specific provisions under the ICNafp. We use yeasts as a prominent example of fungi known from cultures. But viable type material is important not only for yeasts, but also for other cultivable Fungi that are characterized by particular morphological structures (a specific type of spores), growth properties, and secondary metabolites. We summarize potential proposals which, in our opinion, will improve the stability of fungal names, in particular by protecting those names for which the reference material can be traced back to the original isolate., (© 2021. The Author(s).)

Taphrinomycotina is the smallest subphylum of the phylum Ascomycota. It is an assemblage of distantly related early diverging lineages of the phylum, comprising organisms with divergent morphology and ecology; however, phylogenomic analyses support its monophyly. In this study, we report the isolation of a yeast strain, which could not be assigned to any of the currently recognised five classes of Taphrinomycotina. The strain of the novel budding species was recovered from extra virgin olive oil and characterised phenotypically by standard methods. The ultrastructure of the cell wall was investigated by transmission electron microscopy. Comparisons of barcoding DNA sequences indicated that the investigated strain is not closely related to any known organism. Tentative phylogenetic placement was achieved by maximum-likelihood analysis of the D1/D2 domain of the nuclear LSU rRNA gene. The genome of the investigated strain was sequenced, assembled, and annotated. Phylogenomic analyses placed it next to the fission Schizosaccharomyces species. To accommodate the novel species, Novakomyces olei , a novel genus Novakomyces , a novel family Novakomycetaceae, a novel order Novakomycetales, and a novel class Novakomycetes is proposed as well. Functional analysis of genes missing in N. olei in comparison to Schizosaccharomyces pombe revealed that they are biased towards biosynthesis of complex organic molecules, regulation of mRNA, and the electron transport chain. Correlating the genome content and physiology among species of Taphrinomycotina revealed some discordance between pheno- and genotype. N. olei produced ascospores in axenic culture preceded by conjugation between two cells. We confirmed that N. olei is a primary homothallic species lacking genes for different mating types.

During a study of yeast diversity in Azorean vineyards, four strains were isolated which were found to represent a novel yeast species based on the sequences of the internal transcribed spacer (ITS) region (ITS1-5.8S-ITS2) and of the D1/D2 domain of the large subunit (LSU) rRNA gene, together with their physiological characteristics. An additional strain isolated from Drosophila suzukii in Italy had identical D1/D2 sequences and very similar ITS regions (five nucleotide substitutions) to the Azorean strains. Phylogenetic analysis using sequences of the ITS region and D1/D2 domain showed that the five strains are closely related to Clavispora lusitaniae , although with 56 nucleotide differences in the D2 domain. Intraspecies variation revealed between two and five nucleotide differences, considering the five strains of Clavispora santaluciae . Some phenotypic discrepancies support the separation of the new species from their closely related ones, such as the inability to grow at temperatures above 35 °C, to produce acetic acid and the capacity to assimilate starch. Neither conjugations nor ascospore formation were observed in any of the strains. The name Clavispora santaluciae f.a., sp. nov., is proposed to accommodate the above noted five strains (holotype, CBS 16465 T ; MycoBank no., MB 835794).

A novel yeast species of Starmerella vitis f.a. sp. nov. is proposed to accommodate five strains isolated from flowers, grapes and an insect in the Azores, Canada, Hungary, Palau and Taiwan. As the strains were genetically distinct, we used parsimony network analysis based on ITS-D1/D2 sequences to delineate the species in a statistically objective manner. According to sequence comparisons and phylogenetic analysis, the novel species is most closely related to Starmerella lactis-condensi. The two species cannot be distinguished by conventional physiological tests. The type strain of Starmerella vitis f.a., sp. nov. is CBS 16418 T ; Mycobank number MB 835251.

Research Background: In our study, spontaneous alcoholic fermentations were carried out to isolate non- Saccharomyces and Saccharomyces yeasts from grape must from different vine-growing regions in Slovenia. Additionally, the diversity of native Saccharomyces cerevisiae strains was evaluated during the process., Experimental Approach: During spontaneous alcoholic fermentations the yeast population of non- Saccharomyces and Saccharomyces yeasts was sampled. We used eleven microsatellite markers to determine the genetic diversity of S. cerevisiae strains. In addition, different ratios of the indigenous strains of S. cerevisiae , Hanseniaspora uvarum and Starmerella bacillaris were tested for their possible use in alcoholic fermentation with inoculated yeasts by monitoring its course and measuring the concentration of aroma compounds in wine., Results and Conclusions: Sequencing of the internal transcribed spacer (ITS) regions of ribosomal DNA showed that of 64 isolates, 46 strains represent S. cerevisiae and 18 strains belong to non- Saccharomyces yeasts. The identified non- Saccharomyces yeast species were H. uvarum , Pichia kudriavzevii , Saturnispora diversa and S. bacillaris . The dendrogram grouped S. cerevisiae strains into 14 groups. The number of S. cervisiae strains isolated from the musts was 10 (Posavje), 11 (Podravje) and 25 (Primorska vine-growing region). On the other hand, the alcoholic fermentation with inoculated yeasts, in which the native S. cerevisiae strain predominated over H. uvarum and S. bacillaris , gave the most promising result due to the highest alcoholvolume fraction, the lowest acetic acid concentration and significantly higher concentrations of volatile thiols 3-mercaptohexyl acetate (3MHA) and 3-mercaptohexan-1-ol (3MH), 2-methylpropanol, 2-methylbutanol, 3-methylbutanol and 2-phenylethanol) in the produced wine., Novelty and Scientific Contribution: We confirmed the potential use of indigenous S. cerevisiae and non- Saccharomyces yeasts in alcoholic fermentation with inoculated yeasts, which allows the positive properties of the yeast strains to be expressed and good quality wines to be produced. Thus, the results are encouraging for winemakers to create different wine styles associated with a particular terroir using indigenous yeasts., Competing Interests: CONFLICT OF INTEREST The authors declare that they have no conflict of interest.

The adaptation of the yeast Saccharomyces cerevisiae to man-made environments for the fermentation of foodstuffs and beverages illustrates the scientific, social, and economic relevance of microbe domestication. Here we address a yet unexplored aspect of S. cerevisiae domestication, that of the emergence of lineages harboring some domestication signatures but that do not fit completely in the archetype of a domesticated yeast, by studying S. cerevisiae strains associated with processed olives, namely table olives, olive brine, olive oil, and alpechin. We confirmed earlier observations that reported that the Olives population results from a hybridization between S. cerevisiae and S. paradoxus. We concluded that the olive hybrids form a monophyletic lineage and that the S. cerevisiae progenitor belonged to the wine population of this species. We propose that homoploid hybridization gave rise to a diploid hybrid genome, which subsequently underwent the loss of most of the S. paradoxus sub-genome. Such a massive loss of heterozygosity was probably driven by adaptation to the new niche. We observed that olive strains are more fit to grow and survive in olive brine than control S. cerevisiae wine strains and that they appear to be adapted to cope with the presence of NaCl in olive brine through expansion of copy number of ENA genes. We also investigated whether the S. paradoxus HXT alleles retained by the Olives population were likely to contribute to the observed superior ability of these strains to consume sugars in brine. Our experiments indicate that sugar consumption profiles in the presence of NaCl are different between members of the Olives and Wine populations and only when cells are cultivated in nutritional conditions that support adaptation of their proteome to the high salt environment, which suggests that the observed differences are due to a better overall fitness of olives strains in the presence of high NaCl concentrations. Although relic olive hybrids exhibit several characteristics of a domesticated lineage, tangible benefits to humans cannot be associated with their phenotypes. These strains can be seen as a case of adaptation without positive or negative consequences to humans, that we define as a quasi-domestication.

Cell-cycle checkpoints and DNA repair processes protect organisms from potentially lethal mutational damage. Compared to other budding yeasts in the subphylum Saccharomycotina, we noticed that a lineage in the genus Hanseniaspora exhibited very high evolutionary rates, low Guanine-Cytosine (GC) content, small genome sizes, and lower gene numbers. To better understand Hanseniaspora evolution, we analyzed 25 genomes, including 11 newly sequenced, representing 18/21 known species in the genus. Our phylogenomic analyses identify two Hanseniaspora lineages, a faster-evolving lineage (FEL), which began diversifying approximately 87 million years ago (mya), and a slower-evolving lineage (SEL), which began diversifying approximately 54 mya. Remarkably, both lineages lost genes associated with the cell cycle and genome integrity, but these losses were greater in the FEL. E.g., all species lost the cell-cycle regulator WHIskey 5 (WHI5), and the FEL lost components of the spindle checkpoint pathway (e.g., Mitotic Arrest-Deficient 1 [MAD1], Mitotic Arrest-Deficient 2 [MAD2]) and DNA-damage-checkpoint pathway (e.g., Mitosis Entry Checkpoint 3 [MEC3], RADiation sensitive 9 [RAD9]). Similarly, both lineages lost genes involved in DNA repair pathways, including the DNA glycosylase gene 3-MethylAdenine DNA Glycosylase 1 (MAG1), which is part of the base-excision repair pathway, and the DNA photolyase gene PHotoreactivation Repair deficient 1 (PHR1), which is involved in pyrimidine dimer repair. Strikingly, the FEL lost 33 additional genes, including polymerases (i.e., POLymerase 4 [POL4] and POL32) and telomere-associated genes (e.g., Repressor/activator site binding protein-Interacting Factor 1 [RIF1], Replication Factor A 3 [RFA3], Cell Division Cycle 13 [CDC13], Pbp1p Binding Protein [PBP2]). Echoing these losses, molecular evolutionary analyses reveal that, compared to the SEL, the FEL stem lineage underwent a burst of accelerated evolution, which resulted in greater mutational loads, homopolymer instabilities, and higher fractions of mutations associated with the common endogenously damaged base, 8-oxoguanine. We conclude that Hanseniaspora is an ancient lineage that has diversified and thrived, despite lacking many otherwise highly conserved cell-cycle and genome integrity genes and pathways, and may represent a novel, to our knowledge, system for studying cellular life without them., Competing Interests: The authors have declared that no competing interests exist.

A novel yeast species was isolated from the sugar-rich stromata of Cyttaria hariotii collected from two different Nothofagus tree species in the Andean forests of Patagonia, Argentina. Phylogenetic analyses of the concatenated sequence of the rRNA gene sequences and the protein-coding genes for actin and translational elongation factor-1α indicated that the novel species belongs to the genus Hanseniaspora. De novo genome assembly of the strain CRUB 1928T yielded a 10.2-Mbp genome assembly predicted to encode 4452 protein-coding genes. The genome sequence data were compared to the genomes of other Hanseniaspora species using three different methods, an alignment-free distance measure, Kr, and two model-based estimations of DNA-DNA homology values, of which all provided indicative values to delineate species of Hanseniaspora. Given its potential role in a rare indigenous alcoholic beverage in which yeasts ferment sugars extracted from the stromata of Cytarria sp., we searched for the genes that may suggest adaptation of novel Hanseniaspora species to fermenting communities. The SSU1-like gene encoding a sulfite efflux pump, which, among Hanseniaspora, is present only in close relatives to the new species, was detected and analyzed, suggesting that this gene might be one factor that characterizes this novel species. We also discuss several candidate genes that likely underlie the physiological traits used for traditional taxonomic identification. Based on these results, a novel yeast species with the name Hanseniaspora gamundiae sp. nov. is proposed with CRUB 1928T (ex-types: ZIM 2545T = NRRL Y-63793T = PYCC 7262T; MycoBank number MB 824091) as the type strain. Furthermore, we propose the transfer of the Kloeckera species, K. hatyaiensis, K. lindneri and K. taiwanica to the genus Hanseniaspora as Hanseniaspora hatyaiensis comb. nov. (MB 828569), Hanseniaspora lindneri comb. nov. (MB 828566) and Hanseniaspora taiwanica comb. nov. (MB 828567)., Competing Interests: The authors have declared that no competing interests exist.

Budding yeasts (subphylum Saccharomycotina) are found in every biome and are as genetically diverse as plants or animals. To understand budding yeast evolution, we analyzed the genomes of 332 yeast species, including 220 newly sequenced ones, which represent nearly one-third of all known budding yeast diversity. Here, we establish a robust genus-level phylogeny comprising 12 major clades, infer the timescale of diversification from the Devonian period to the present, quantify horizontal gene transfer (HGT), and reconstruct the evolution of 45 metabolic traits and the metabolic toolkit of the budding yeast common ancestor (BYCA). We infer that BYCA was metabolically complex and chronicle the tempo and mode of genomic and phenotypic evolution across the subphylum, which is characterized by very low HGT levels and widespread losses of traits and the genes that control them. More generally, our results argue that reductive evolution is a major mode of evolutionary diversification., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Six yeast strains isolated from olive oil sediments and spoiled olive oils originating from Slovenia and Portugal, respectively, proved to represent an undescribed yeast species based on DNA sequence comparisons. The analysis of gene sequences for internal transcribed spacer regions and the large subunit rRNA gene D1/D2 domain placed the novel species in the genus Kuraishia in a subclade containing Kuraishiacapsulata, the type species of the genus. Although the novel species is well separated genetically from the recognized species of the genus, only a minor phenotypic difference differentiating it from Kuraishia capsulata and K. molischiana was observed. Relevant to its isolation source, no lipolytic activity was detected in the strains of the novel species. To accommodate the above-noted strains, Kuraishia mediterranea sp. nov. (holotype: ZIM 2473 T ; isotype: CBS 15107 T ; MycoBank no.: MB 822817) is proposed.

Two yeast strains representing a hitherto undescribed yeast species were isolated from olive oil and spoiled olive oil originating from Spain and Israel, respectively. Both strains are strong acetic acid producers, equipped with considerable tolerance to acetic acid. The cultures are not short-lived. Cellobiose is fermented as well as several other sugars. The sequences of their large subunit (LSU) rRNA gene D1/D2 domain are very divergent from the sequences available in the GenBank. They differ from the closest hit, Brettanomyces naardenensis by about 27%, mainly substitutions. Sequence analyses of the concatenated dataset from genes of the small subunit (SSU) rRNA, LSU rRNA and translation elongation factor-1α (EF-1α) placed the two strains as an early diverging member of the Brettanomyces/Dekkera clade with high bootstrap support. Sexual reproduction was not observed. The name Brettanomyces acidodurans sp. nov. (holotype: NCAIM Y.02178 T ; isotypes: CBS 14519 T  = NRRL Y-63865 T  = ZIM 2626 T , MycoBank no.: MB 819608) is proposed for this highly divergent new yeast species.

Artisanal white pickled cheese of Western Serbia is a product of complex microbial community which detection by culture-dependent method only is hampered by its limitations. Thus, in the present study, we used a culture-independent, semi-quantitative technique based on construction of an internal transcribed spacer (ITS)-clone library from metagenomic DNA. This approach, based on direct DNA extraction followed by amplification of fungal internal transcribed regions (ITS) cloned into plasmid and restricted by endonucleases, revealed greater species richness in analysed cheeses and their by-products (17 species in total) compared to the more commonly used techniques of the culture-dependent method (8 species) and LSU-DGGE (10 species). The most frequently occurring yeast species which are commonly associated with cheeses production were Debaryomyces hansenii, Kluyveromyces lactis and Candida zeylanoides. On the other hand, Yarrowia lipolytica and Galactomyces geotrichum were detected only in one cheese sample. Moreover, some species, mainly moulds (Filobasidium globisporum, Cladosporium sp., Aspergillus sp. or Alternaria sp.) were identified only by culture-independent methods. The discrepancies between the techniques were confirmed by low correlation factor and by different indices of general biodiversity and dominance of species. The ITS-clone library approach provides the opportunity to analyse complex fungal communities associated with food products.

Campylobacteriosis is the leading zoonosis in the European Union with the majority of cases attributed to Campylobacter jejuni. Although the disease is usually self-limiting, some severe cases need to be treated with antibiotics, primarily macrolides and quinolones. However, the resistance to the latter is reaching alarming levels in most of the EU countries. To shed light on the expansion of antibiotic resistance in central Europe, we have investigated genetic similarity across 178 ciprofloxacin-resistant C. jejuni mostly isolated in Slovenia, Austria and Germany. We performed comparative genetic similarity analyses using allelic types of seven multilocus sequence typing housekeeping genes, and single nucleotide polymorphisms of a quinolone resistance determining region located within the DNA gyrase subunit A gene. This analysis revealed high genetic similarity of isolates from clonal complex ST-21 that carry gyrA allelic type 1 in all three of these central-European countries, suggesting these ciprofloxacin resistant isolates arose from a recent common ancestor and are spread clonally.

Five yeast strains representing a hitherto undescribed yeast species were isolated from bee bread and honey in Hungary. They are obligate osmophilic, i.e. they are unable to grow in/on high water activity culture media. Following isogamous conjugation, they form 1-4 spheroid or subspheroid ascospores in persistent asci. The analysis of the sequences of their large subunit rRNA gene D1/D2 domain placed the new species in the Zygosaccharomyces clade. In terms of pairwise sequence similarity, Zygosaccharomyces gambellarensis is the most closely related species. Comparisons of D1/D2, internal transcribed spacer and translation elongation factor-1α (EF-1α) gene sequences of the five strains with that of the type strain of Z. gambellarensis revealed that they represent a new yeast species. The name Zygosaccharomyces favi sp. nov. (type strain: NCAIM Y.01994(T) = CBS 13653(T) = NRRL Y-63719(T) = ZIM 2551(T)) is proposed for this new yeast species, which based on phenotype can be distinguished from related Zygosaccharomyces species by its obligate osmophilic nature. Some intragenomic sequence variability, mainly indels, was detected among the ITS copies of the strains of the new species.

Aim: The aim of this study was to investigate the in vitro probiotic potential of dairy yeast isolates from artisanal cheeses manufactured in Serbia and Croatia., Materials and Methods: Twelve yeast strains isolated from artisanal fresh soft and white brined cheeses manufactured in Serbia and Croatia were used in the study. Survival in chemically-simulated gastrointestinal conditions, adherence to epithelial intestinal cells and proliferation of gut-associated lymphoid tissue (GALT) cells were evaluated., Results: The results revealed that two strains of Kluyvereomyces lactis ZIM 2408 and ZIM 2453 grew above one log unit (Δ log CFU/ml) in the complex colonic medium during 24 h of cultivation, while Torulaspora delbrueckii ZIM 2460 was the most resistant isolate in chemically-simulated conditions of gastric juice and upper intestinal tract. It was demonstrated that the strains K. lactis ZIM 2408 and ZIM2441 and Saccharomyces cerevisiae ZIM 2415 were highly adhesive to Caco-2 cells, while strains K. lactis ZIM 2408 and Debaryomyces hansenii ZIM 2415 exhibit the highest adhesion percentage to HT29-MTX cells. All strains significantly (P < 0.0001) decreased the proliferation of GALT cells, suggesting the possible strain-specific immunomodulatory potential of the isolates., Conclusion: The dairy yeast isolates exhibit strain-specific probiotic properties, particularly the strain K. lactis ZIM 2408, which appears to be the best probiotic candidate in terms of all three criteria. Taking into account their immunomodulatory potential, the yeast isolates could be further tested for specific probiotic applications and eventually included in functional food formulated for patients suffering from diseases associated with an increased inflammatory status.

Seven apiculate yeast strains that were isolated from the flowers of Syphocampylus corymbiferus Pohl in Brazil are genetically, morphologically and phenotypically distinct from recognized species of the genera Hanseniaspora and Kloeckera. Genetic discontinuities between the novel strains and their closest relatives were found using a networking approach based on the concatenated sequences of the rRNA gene (internal transcribed spacer and D1/D2 of the LSU), and the protein-coding genes for actin and translation elongation factor-1α. Phylogenetic analysis based on the rRNA and the actin gene placed the novel species represented by the strains in close relationship to Hanseniaspora meyeri and Hanseniaspora clermontiae. PCR fingerprinting with microsatellite primers confirmed the genetic heterogeneity of the novel species. The name Hanseniaspora nectarophila sp. nov. is proposed, with UFMG POG a.1(T) ( = ZIM 2311(T)  = CBS 13383(T)) as the type strain; MycoBank no. MB807210. As the current description of the genus does not allow the presence of multilateral budding, an emended diagnosis of the genus Hanseniaspora Zikes is proposed., (© 2014 IUMS.)

Nine methanol-assimilating yeast strains isolated from olive oil sediments in Slovenia, extra virgin olive oil from Italy and rotten wood collected in Hungary were found to form three genetically separated groups, distinct from the currently recognized yeast species. Sequence analysis from genes of the small subunit (SSU) rRNA, internal transcribed spacer region/5.8S rRNA, large subunit (LSU) rRNA D1/D2 domains and translational elongation factor-1α (EF-1α) revealed that the three closely related groups represent three different undescribed yeast species. Sequence analysis of the LSU rRNA gene D1/D2 domains placed the novel species in the Ogataea clade. The three novel species are designated as Ogataea kolombanensis sp. nov. (type strain: ZIM 2322(T) = CBS 12778(T) = NRRL Y-63657(T)), Ogataea histrianica sp. nov. (type strain: ZIM 2463(T) = CBS 12779(T) = NRRL Y-63658(T)) and Ogataea deakii sp. nov. (type strain: NCAIM Y.01896(T) = CBS 12735(T) = NRRL Y-63656(T)).

Thirteen strains isolated from virgin olive oil or its by-products in several Mediterranean countries were found to be phenotypically and genetically divergent from currently recognized yeast species. Sequence analysis of the large subunit (LSU) rDNA D1/D2 domain and internal transcribed spacer regions/5.8S rDNA revealed that the strains represented two novel species described as Candida adriatica sp. nov. (type strain ZIM 2334(T) = CBS 12504(T) = NCAIM Y.02001(T)) and Candida molendinolei sp. nov. (type strain DBVPG 5508(T) = CBS 12508(T) = NCAIM Y.02000(T)). Phylogenetic analysis based on concatenated sequences of the small subunit rRNA gene, the D1/D2 region of the LSU rDNA and the translation elongation factor-1α gene suggested that C. adriatica sp. nov. and C. molendinolei sp. nov. should be placed within the Lindnera and Nakazawaea clades, respectively.