Genome-scale phylogeny and comparative genomics of the fungal order Sordariales.

The order Sordariales is taxonomically diverse, and harbours many species with different lifestyles and large economic importance. Despite its importance, a robust genome-scale phylogeny, and associated comparative genomic analysis of the order is lacking. In this study, we examined whole-genome data from 99 Sordariales, including 52 newly sequenced genomes, and seven outgroup taxa. We inferred a comprehensive phylogeny that resolved several contentious relationships amongst families in the order, and cleared-up intrafamily relationships within the Podosporaceae. Extensive comparative genomics showed that genomes from the three largest families in the dataset (Chaetomiaceae, Podosporaceae and Sordariaceae) differ greatly in GC content, genome size, gene number, repeat percentage, evolutionary rate, and genome content affected by repeat-induced point mutations (RIP). All genomic traits showed phylogenetic signal, and ancestral state reconstruction revealed that the variation of the properties stems primarily from within-family evolution. Together, the results provide a thorough framework for understanding genome evolution in this important group of fungi.

Diverse members of the Xylariales lack canonical mating-type regions.

A survey of genomes reported here for 10 isolates of Monosporascus species and an additional 25 genomes from other members of the Xylariales (representing 15 genera) available in public databases indicated that genes typically associated with MAT1-1 (mat A) or MAT1-2 (mat a) mating types are absent or have diverged greatly relative to counterparts in other Pezizomycotina. This was particularly surprising for isolates known to be homothallic, given that homothallic members of the Pezizomycotina typically possess a MAT1-1-1 (mat A-1) gene and one or both of two other closely-linked mating-type genes, MAT1-1-2 (mat A-2) and MAT1-1-3 (mat A-3), in addition to MAT1-2-1 (mat a-1). We failed to detect candidate genes for either MAT1-1-1 or MAT1-1-2 in any member of the Xylariales. Genes related to MAT1-2-1 and MAT1-1-3 are present in the genomes examined, but most appear to be orthologs of MATA_HMG (high-mobility group) genes with non-mating-type functions rather than orthologs of mating-type genes. Several MATA_HMG genes were found in genome positions that suggest they are derived from mating-type genes, but these genes are highly divergent relative to known MAT1-2-1 and MAT1-1-3 genes. The genomes examined represent substantial diversity within the order and include M. cannonballus, M. ibericus, Xylaria hypoxylon, X. striata, Daldinia eschscholzii, Eutypa lata, Rosellinia necatrix, Microdochium bolleyi and several others. We employed a number of avenues to search for homologs, including multiple BLAST approaches and examination of annotated genes adjacent to genes known to flank mating regions in other members of the Ascomycota. The results suggest that the mating regions have been lost from, or altered dramatically in, the Xylariales genomes examined and that mating and sexual development in these fungi are controlled differently than has been reported for members of the Pezizomycotina studied to date.

Experimental drought reduces genetic diversity in the grassland foundation species Bouteloua eriopoda.

Understanding the resistance and resilience of foundation plant species to climate change is a critical issue because the loss of these species would fundamentally reshape communities and ecosystem processes. High levels of population genetic diversity may buffer foundation species against climate disruptions, but the strong selective pressures associated with climatic shifts may also rapidly reduce such diversity. We characterized genetic diversity and its responsiveness to experimental drought in the foundation plant, black grama grass (Bouteloua eriopoda), which dominates many western North American grasslands and shrublands. Previous studies suggested that in arid ecosystems, black grama reproduces largely asexually via stolons, and thus is likely to have low genetic variability, which might limit its potential to respond to climate disruptions. Using genotyping-by-sequencing, we demonstrated unexpectedly high genetic variability among black grama plants in a 1 ha site within the Sevilleta National Wildlife Refuge in central New Mexico, suggesting some level of sexual reproduction. Three years of experimental, growing season drought reduced black grama survival and biomass (the latter by 96%), with clear genetic differentiation (higher FST) between plants succumbing to drought and those remaining alive. Reduced genetic variability in the surviving plants in drought plots indicated that the experimental drought had forced black grama populations through selection bottlenecks. These results suggest that foundation grass species, such as black grama, may experience rapid evolutionary change if future climates include more severe droughts.

Genetics of mating in members of the Chaetomiaceae as revealed by experimental and genomic characterization of reproduction in Myceliophthora heterothallica.

Members of the Chaetomiaceae are among the most studied fungi in industry and among the most reported in investigations of biomass degradation in both natural and laboratory settings. The family is recognized for production of carbohydrate-active enzymes and antibiotics. Thermophilic species are of special interest for their abilities to produce thermally stable enzymes and to be grown under conditions that are unsuitable for potential contaminant microorganisms. Such interests led to the recent acquisition of genome sequences from several members of the family, including thermophilic species, several of which are reported here for the first time. To date, however, thermophilic fungi in industry have served primarily as parts reservoirs and there has been no good genetic model for species in the family Chaetomiaceae or for thermophiles in general. We report here on the reproductive biology of the thermophile Myceliophthora heterothallica, which is heterothallic, unlike most described species in the family. We confirmed heterothallism genetically by following the segregation of mating type idiomorphs and other markers. We have expanded the number of known sexually-compatible individuals from the original isolates from Indiana and Germany to include several isolates from New Mexico. An interesting aspect of development in M. heterothallica is that ascocarp formation is optimal at approximately 30 °C, whereas vegetative growth is optimal at 45 °C. Genome sequences obtained from several strains, including isolates of each mating type, revealed mating-type regions whose genes are organized similarly to those of other members of the Sordariales, except for the presence of a truncated version of the mat A-1 (MAT1-1-1) gene in mating-type a (MAT1-2) strains. In M. heterothallica and other Chaetomiaceae, mating-type A (MAT1-1) strains have the full-length version of mat A-1 that is typical of mating-type A strains of diverse Ascomycota, whereas a strains have only the truncated version. This truncated mat A-1 has an intact open reading frame and a derived start codon that is not present in mat A-1 from A strains. The predicted protein contains a region that is conserved across diverse mat A-1 genes, but it lacks the major alpha1 domain, which characterizes proteins in this family and is known to be required for fertility in A strains from other Ascomycota. Finally, we have used genes from M. heterothallica to probe for mating genes in other homothallic and heterothallic members of the Chaetomiaceae. The majority of homothallic species examined have a typical mat A-1,2,3 (MAT1-1-1,2,3) region in addition to an unlinked mat a-1 (MAT1-2-1) gene, reflecting one type of homothallism commonly observed in diverse Ascomycota.

Lignin-modifying processes in the rhizosphere of arid land grasses.

Genes associated with elevated oxidative enzyme activities in arid systems have not been well characterized. To link measured oxidative activities with specific enzymes, we assembled protein-coding reads from the rhizospheres (RHZ) of two arid land grasses. Targeted gene scans for open reading frames, encoding genes potentially involved in lignin modification, resulted in 127 distinct assembly products. The putative genes included those significantly similar to Class II secretory fungal peroxidases. These genes are expressed at sufficiently high levels for assembly, annotation and differentiation across experimental conditions, and they demonstrate the interplay of root systems, environment and plant microbiomes. The genes assembled also included copper-dependent lytic polysaccharide monooxygenases. We detail the enzymes in the host grass RHZs and present a preliminary taxonomic microhabitat characterization. Our findings provide support for biologically mediated Fenton chemistry in the root zones of desert grasses, and provide insight into arid land carbon flow. These results also demonstrate a hyperdiverse microbial community. Both ribosomal RNA and messenger RNA sequences were dominated by bacteria, followed by fungal sequence abundance. Among the notable fungal sequences were those from the members of the arbuscular mycorrhizal fungi (Glomeromycota), which though abundant in this study, we rarely observed in previous PCR-based surveys.

Mycothermus thermophilus gen. et comb. nov., a new home for the itinerant thermophile Scytalidium thermophilum (Torula thermophila).

Thermophilic fungi have received substantial attention in industry for their potential to produce thermostable enzymes and as production platforms tolerant of high temperature. Studies exploring the ecology and biosystematics of thermophilic fungi have lagged behind studies in applied biology. The species commonly known as Scytalidium thermophilum (Chaetomiaceae) is one of the most frequently encountered organisms in surveys of thermophilic fungi. There is evidence that it is ecologically and economically important, for example in the context of commercial mushroom growing. As described here, this species should not be placed in the genus Scytalidium or any other existing genus. We propose a new genus and combination, Mycothermus thermophilus.

Insights into evolution of multicellular fungi from the assembled chromosomes of the mushroom Coprinopsis cinerea (Coprinus cinereus).

The mushroom Coprinopsis cinerea is a classic experimental model for multicellular development in fungi because it grows on defined media, completes its life cycle in 2 weeks, produces some 10(8) synchronized meiocytes, and can be manipulated at all stages in development by mutation and transformation. The 37-megabase genome of C. cinerea was sequenced and assembled into 13 chromosomes. Meiotic recombination rates vary greatly along the chromosomes, and retrotransposons are absent in large regions of the genome with low levels of meiotic recombination. Single-copy genes with identifiable orthologs in other basidiomycetes are predominant in low-recombination regions of the chromosome. In contrast, paralogous multicopy genes are found in the highly recombining regions, including a large family of protein kinases (FunK1) unique to multicellular fungi. Analyses of P450 and hydrophobin gene families confirmed that local gene duplications drive the expansions of paralogous copies and the expansions occur in independent lineages of Agaricomycotina fungi. Gene-expression patterns from microarrays were used to dissect the transcriptional program of dikaryon formation (mating). Several members of the FunK1 kinase family are differentially regulated during sexual morphogenesis, and coordinate regulation of adjacent duplications is rare. The genomes of C. cinerea and Laccaria bicolor, a symbiotic basidiomycete, share extensive regions of synteny. The largest syntenic blocks occur in regions with low meiotic recombination rates, no transposable elements, and tight gene spacing, where orthologous single-copy genes are overrepresented. The chromosome assembly of C. cinerea is an essential resource in understanding the evolution of multicellularity in the fungi.

Thermophilic fungi in an aridland ecosystem.

We report a comprehensive multi-year study of thermophilic fungi at the Sevilleta National Wildlife Refuge in central New Mexico. Recovery of thermophilic fungi from soils showed seasonal fluctuations, with greater abundance correlating with spring and summer precipitation peaks. In addition to grassland soils, we obtained and characterized isolates from grassland and riparian litter, herbivore dung and biological soil crusts. All strains belonged to either the Eurotiales or Sordariales (Chaetomiaceae). No particular substrate or microhabitat associations were detected. Molecular typing of strains revealed substantial phylogenetic diversity, eight ad hoc phylogroups across the two orders were identified and genetic diversity was present within each phylogroup. Growth tests over a range of temperatures showed substantial variation in maximum growth rates among strains and across phylogroups but consistency within phylogroups. Results demonstrated that 45-50 C represents the optimal temperature for growth of most isolates, with a dramatic decline at 60 C. Most strains grew at 60 C, albeit slowly, whereas none grew at 65 C, providing empirical confirmation that 60 C presents an evolutionary threshold for fungal growth. Our results support the hypothesis that fungal thermophily is an adaptation to transient seasonal and diurnal high temperatures, rather than simply an adaptation to specialized high-temperature environments. We note that the diversity observed among strains and the frequently confused taxonomy within these groups highlight the need for comprehensive biosystematic revision of thermophilic taxa in both orders.

Breathing can be dangerous: Opportunistic fungal pathogens and the diverse community of the small mammal lung mycobiome.

Human lung mycobiome studies typically sample bronchoalveolar lavage or sputum, potentially overlooking fungi embedded in tissues. Employing ultra-frozen lung tissues from biorepositories, we obtained fungal ribosomal RNA ITS2 sequences from 199 small mammals across 39 species. We documented diverse fungi, including common environmental fungi such as Penicillium and Aspergillus, associates of the human mycobiome such as Malassezia and Candida, and others specifically adapted for lungs (Coccidioides, Blastomyces, and Pneumocystis). Pneumocystis sequences were detected in 83% of the samples and generally exhibited phylogenetic congruence with hosts. Among sequences from diverse opportunistic pathogens in the Onygenales, species of Coccidioides occurred in 12% of samples and species of Blastomyces in 85% of samples. Coccidioides sequences occurred in 14 mammalian species. The presence of neither Coccidioides nor Aspergillus fumigatus correlated with substantial shifts in the overall mycobiome, although there was some indication that fungal communities might be influenced by high levels of A. fumigatus. Although members of the Onygenales were common in lung samples (92%), they are not common in environmental surveys. Our results indicate that Pneumocystis and certain Onygenales are common commensal members of the lung mycobiome. These results provide new insights into the biology of lung-inhabiting fungi and flag small mammals as potential reservoirs for emerging fungal pathogens.

Diversity and distribution of soil fungal communities in a semiarid grassland.

The fungal loop model of semiarid ecosystems integrates microtopographic structures and pulse dynamics with key microbial processes. However limited data exist about the composition and structure of fungal communities in these ecosystems. The goal of this study was to characterize diversity and structure of soil fungal communities in a semiarid grassland. The effect of long-term nitrogen fertilization on fungi also was evaluated. Samples of rhizosphere (soil surrounding plant roots) and biological soil crust (BSC) were collected in central New Mexico, USA. DNA was amplified from the samples with fungal specific primers. Twelve clone libraries were generated with a total of 307 (78 operational taxonomic units, OTUs) and 324 sequences (67 OTUs) for BSC and rhizosphere respectively. Approximately 40% of soil OTUs were considered novel (less than 97% identity when compared to other sequences in NCBI using BLAST). The dominant organisms were dark-septate (melanized fungi) ascomycetes belonging to Pleosporales. Effects of N enrichment on fungi were not evident at the community level; however the abundance of unique sequences, sampling intensity and temporal variations may be uncovering the effect of N in composition and diversity of fungal communities. The fungal communities of rhizosphere soil and BSC overlapped substantially in composition, with a Jaccard abundance similarity index of 0.75. Further analyses are required to explore possible functions of the dominant species colonizing zones of semiarid grassland soils.

Shifting fungal endophyte communities colonize Bouteloua gracilis: effect of host tissue and geographical distribution.

Communities of root-associated fungi (RAF) commonly have been studied under the auspices of arbuscular mycorrhizal fungi (AMF) or ectomycorrhizal fungi. However many studies now indicate that other groups of endophytic RAF, including dark septate endophytes (DSE) are more abundant in some plants and environments. The common forage grass, Bouteloua gracilis, was used as a model to examine whether RAF also colonize different organs within the same plant and to compare RAF communities from sites across North America, spanning the latitudinal range of B. gracilis (from Canada to Mexico). We compared the RAF communities of organs within individual plants at one site and within plant roots among six sites. With the possible exception of one group related to genus Paraphaeosphaeria there was little evidence that RAF colonized vertically beyond the crowns. Furthermore, although there was some variation in the constitution of rare members of the RAF communities, several taxonomically related groups dominated the RAF community at all sites. These dominant taxa included members in the Pleosporales (related to the DSE, Paraphaeosphaeria spp.), Agaricales (related to Moniliophthora spp., or Campanella spp.) and Hypocreales (related to Fusarium spp.). AMF were notable by their near absence. Similar phylotypes from the dominant groups clustered around adjacent sites so that similarity of the RAF communities was negatively correlated to site inter-distance and the RAF communities appeared to group by country. These results increase the possibility that at least some of these common and widely distributed core members of the RAF community form important, intimate and long lasting relationships with grasses.

Genomic Analysis of Diverse Members of the Fungal Genus Monosporascus Reveals Novel Lineages, Unique Genome Content and a Potential Bacterial Associate.

The genus Monosporascus represents an enigmatic group of fungi important in agriculture and widely distributed in natural arid ecosystems. Of the nine described species, two (M. cannonballus and M. eutypoides) are important pathogens on the roots of members of Cucurbitaceae in agricultural settings. The remaining seven species are capable of colonizing roots from a diverse host range without causing obvious disease symptoms. Recent molecular and culture studies have shown that members of the genus are nearly ubiquitous as root endophytes in arid environments of the Southwestern United States. Isolates have been obtained from apparently healthy roots of grasses, shrubs and herbaceous plants located in central New Mexico and other regions of the Southwest. Phylogenetic and genomic analyses reveal substantial diversity in these isolates. The New Mexico isolates include close relatives of M. cannonballus and M. ibericus, as well as isolates that represent previously unrecognized lineages. To explore evolutionary relationships within the genus and gain insights into potential ecological functions, we sequenced and assembled the genomes of three M. cannonballus isolates, one M. ibericus isolate, and six diverse New Mexico isolates. The assembled genomes were significantly larger than what is typical for the Sordariomycetes despite having predicted gene numbers similar to other members of the class. Differences in predicted genome content and organization were observed between endophytic and pathogenic lineages of Monosporascus Several Monosporascus isolates appear to form associations with members of the bacterial genus Ralstonia (Burkholdariaceae).

First Analysis of Human Coccidioides Isolates from New Mexico and the Southwest Four Corners Region: Implications for the Distributions of C. posadasii and C. immitis and Human Groups at Risk.

Coccidioidomycosis (Valley Fever) is a disease caused by species of Coccidioides. The disease is endemic to arid regions of the Southwestern US and while most common in CA and AZ is also present in NM. We present the first genetic analysis of clinical isolates from NM. Travel and demographic information was available for a number of patients, which included individuals from NM and the Southwestern US Four Corners region. Multi-gene phylogenetic analyses revealed the presence of both C. posadasii and C. immitis. While NM is predicted to be within the endemic range for C. posadasii, our results expand the known range of C. immitis, often considered to be the "California species". Five of eight infections for which patient ethnicity existed occurred in Native Americans, and two occurred in African Americans. Several isolates came from the northwestern part of NM-outside the predicted "highly-endemic" region. Our study suggests Native Americans represent an unrecognized at-risk group, and it provides a foundation for better defining the geographic distribution of the Coccidioides species and for preventing exposure among populations at risk. In the course of this study, we developed a reliable PCR-based method to distinguish species targeting regions of the mitochondrial genome.

Diversity of thermophilic and thermotolerant fungi in corn grain.

Corn bins in the midwestern United States can reach temperatures up to 52 C. High temperatures combined with sufficient moisture and humidity in bins provide the perfect environment to promote the growth of thermophilic and thermotolerant fungi. In this article, we characterize for the first time thermophilic and thermotolerant fungi in corn grain bins using culture-based methods and pyrosequencing techniques. Corn samples were collected from local farms in western Illinois. Samples were plated and incubated at 50 C using a variety of approaches. Of several hundred kernels examined, more than 90% showed colonization. Species identified using culture methods included Thermomyces lanuginosus, Thermomyces dupontii, Aspergillus fumigatus, Thermoascus crustaceus, and Rhizomucor pusillus. Pyrosequencing was also performed directly on corn grain using fungal-specific primers to determine whether thermophilic fungi could be detected using this technique. Sequences were dominated by pathogenic fungi, and thermophiles were represented by less than 2% of the sequences despite being isolated from 90% of the grain samples using culturing techniques. The high abundance of previously undocumented viable fungi in corn could have negative implications for grain quality and pose a potential risk for workers and consumers of corn-derived products in the food industry. Members of the Sordariales were absent among thermophile isolates and were not represented in nuc rDNA internal transcribed spacer (ITS) sequences. This is in striking contrast with results obtained with other substrates such as litter, dung, and soils, where mesophilic and thermophilic members of the Sordariaceae and Chaetomiaceae are common. This absence appears to reflect an important difference between the ecology of Sordariales and other orders within the Ascomycota in terms of their ability to compete in microhabitats rich in sugars and living tissues.

Novel root fungal consortium associated with a dominant desert grass.

The broad distribution and high colonization rates of plant roots by a variety of endophytic fungi suggest that these symbionts have an important role in the function of ecosystems. Semiarid and arid lands cover more than one-third of the terrestrial ecosystems on Earth. However, a limited number of studies have been conducted to characterize root-associated fungal communities in semiarid grasslands. We conducted a study of the fungal community associated with the roots of a dominant grass, Bouteloua gracilis, at the Sevilleta National Wildlife Refuge in New Mexico. Internal transcribed spacer ribosomal DNA sequences from roots collected in May 2005, October 2005, and January 2006 were amplified using fungal-specific primers, and a total of 630 sequences were obtained, 69% of which were novel (less than 97% similarity with respect to sequences in the NCBI database). B. gracilis roots were colonized by at least 10 different orders, including endophytic, coprophilous, mycorrhizal, saprophytic, and plant pathogenic fungi. A total of 51 operational taxonomic units (OTUs) were found, and diversity estimators did not show saturation. Despite the high diversity found within B. gracilis roots, the root-associated fungal community is dominated by a novel group of dark septate fungi (DSF) within the order Pleosporales. Microscopic analysis confirmed that B. gracilis roots are highly colonized by DSF. Other common orders colonizing the roots included Sordariales, Xylariales, and Agaricales. By contributing to drought tolerance and nutrient acquisition, DSF may be integral to the function of arid ecosystems.

Regulation and oxidation of two large monofunctional catalases.

The two Neurospora crassa catalase genes cat-1 and cat-3 were shown to encode Cat-1 and Cat-3 large monofunctional catalases. cat-1 and cat-3 genes are regulated differentially during the asexual life cycle and under stress conditions. A stepwise increase in catalase activity occurs during conidiation. Conidia have 60 times more catalase activity than exponentially growing hyphae. Cat-1 activity was predominant in conidia, during germination and early exponential growth. It was induced during prestationary growth and by ethanol or heat shock. Cat-3 activity was predominant during late exponential growth and at the start of the conidiation process. It was induced under stress conditions, such as H(2)O(2), paraquat, cadmium, heat shock, uric acid, and nitrate treatment. In general, Cat-1 activity was associated with nongrowing cells and Cat-3 activity with growing cells. The Cat-3 N-terminus sequence indicates that this catalase is processed and presumably secreted. Paraquat caused modification and degradation of Cat-1. Under heat shock both Cat-1 and Cat-3 were modified and degraded and Cat-1 was resynthesized. Paraquat and heat shock effects were observed only in the presence of air and are probably related to in vivo generation of singlet oxygen. Purified Cat-3 was modified with a photosensitizing reaction in which singlet oxygen is produced.

Variation among natural isolates of Neurospora on small spatial scales.

Although species of Neurospora are among the most studied model organisms in genetics and biochemistry, basic questions remain with respect to their ecology and population biology. In this study, we sought to clarify relationships among individuals over a small spatial scale, toward assessing both local variation and mode of colonization. Isolates of Neurospora were collected after fires in the Florida Everglades (May 1999), where abundant colonies appeared on diverse plants, including grasses and woody shrubs. Colonies were sampled in a linear fashion from two adjacent scorched sugarcane stems at one site and from a burned woody shrub at a distant second site. Species and mating types were assigned based on crossing behavior. Variation at two loci, het-c and frq, was determined by direct sequencing of PCR products. The results demonstrated substantial within- and among-species variation on a small scale, with up to three species and six different haplotypes occurring on a single stem. In total, four species and more than 10 genetically distinct individuals (haplotypes) were present across the three stems, often with multiple individuals occupying the same position. A permutation analysis revealed that individuals were not distributed randomly and that adjacent nodes on cane stems were more likely than chance to be colonized by the same haplotype. This suggests that visible eruptions of conidia on burned plants reflect substantial vegetative mycelial spread through subsurface tissues after primary colonization. Results also revealed that adjacent isolates from a single plant can possess different functional alleles at het-c, an observation meaningful in the context of the proposed role of het-c in self recognition.

Neurospora in temperate forests of western North America.

The fungal genus Neurospora has a distinguished history as a laboratory model in genetics and biochemistry. The most recent milestone in this history has been the sequencing of the genome of the best known species, N. crassa. The hope and promise of a complete genome sequence is a full understanding of the biology of the organism. Full understanding cannot be achieved, however, in the absence of fundamental knowledge of natural history. We report that species of Neurospora, heretofore thought to occur mainly in moist tropical and subtropical regions, are common primary colonizers of trees and shrubs killed by forest fires in western North America, in regions that are often cold and dry. Surveys in 36 forest-fire sites from New Mexico to Alaska yielded more than 500 cultures, 95% of which were the rarely collected N. discreta. Initial characterization of genotypes both within a site and on a single tree showed diversity consistent with sexual reproduction of N. discreta. These discoveries fill important gaps in knowledge of the distribution of members of the genus on both large and small spatial scales and provide the framework for future studies in new regions and microhabitats. The overall result is that population biology and genetics now can be combined, placing the genus Neurospora in a unique position to expand its role in experimental biology as a useful model organism for ecology, population genetics and evolution.

Antimicrobial activity of cationic conjugated polyelectrolytes and oligomers against Saccharomyces cerevisiae vegetative cells and ascospores.

The antifungal activities of poly(phenylene ethynylene) (PPE)-based cationic conjugated polyelectrolytes (CPEs) and oligo-phenylene ethynylenes (OPEs) were investigated using Saccharomyces cerevisiae (S. cerevisiae) as a model pathogen. The effect of the CPE and OPE materials on the vegetative cells and ascospores were tested in the dark or with UV-irradiation. A number of the tested polymers and oligomers significantly reduced the viability of the vegetative yeast cells in the dark, with activities exceeding the commonly used antibiotic Amphotericin B. With UV-irradiation, all of the tested CPEs and OPEs exhibited potent antifungal activities and completely inactivated the yeast cells. In particular, the oligomeric EO-OPE-1(Th, C2) strongly inactivates ascospores with UV-light at a dose level lower than sporicidal agents reported in the literature. Under conditions that promote spore germination, the CPEs and OPEs show efficient activities against the germinated spores. The protein-enriched outer envelope of yeast cells and germinated ascospores appears to serve as a main target for the CPE and OPE antimicrobial materials.