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Arthrobotrys flagrans, a nematode‐eating fungus, is an effective component of animal parasitic nematode biocontrol agents. In the dried formulation, the majority of spores are in an endogenous dormant state. This study focuses on dormant chlamydospore and nondormant chlamydospore of A. flagrans to investigate the differences in cyclic adenosine monophosphate (cAMP) and protein content between the two types of spores. cAMP and soluble proteins were extracted from the nondormant chlamydospore and dormant chlamydospore of two isolates of A. flagrans. The cAMP Direct Immunoassay Kit and Bradford protein concentration assay kit (Coomassie brilliant blue method) were used to detect the cAMP and protein content in two types of spores. Results showed that the content of cAMP in dormant spores of both isolates was significantly higher than that in nondormant spores (p < 0.05). The protein content of dormant spores in DH055 bacteria was significantly higher than that of nondormant spores (p < 0.05). In addition, the protein content of dormant spores of the SDH035 strain was slightly higher than that of nondormant spores, but the difference was not significant (p > 0.05). The results obtained in this study provide evidence for the biochemical mechanism of chlamydospore dormancy or the germination of the nematophagous fungus A. flagrans. [ABSTRACT FROM AUTHOR]

Aims Chlamydospores are a special, differentiated type with high environmental resistance. Consequently, the chlamydospores of Trichoderma harzianum T4 can used to industrialize the latter. This study aimed to investigate the key factors affecting the sporulation type of T. harzianum T4 and the mechanisms underlying this effect. Methods and results In the liquid fermentation of T. harzianum T4, ammonium sulfate (AS) inhibited conidia formation and chlamydospore production. Fermentation tests revealed that acid stress induced sporulation type alteration. Transcriptomic analysis was used to evaluate the adaptation strategy and mechanism underlying spore type alteration under acid stress. The fermentation experiments involving the addition of amino acids revealed that branched-chain amino acids benefited conidia production, whereas β-alanine benefited chlamydospore production. Confocal microscope fluorescence imaging and chloroquine intervention demonstrated that vacuole function was closely related to chlamydospore production. Conclusion The sporulation type of T. harzianum T4 can be controlled by adjusting the fermentation pH. T. harzianum T4 cells employ various self-protection measures against strong acid stress, including regulating their metabolism to produce a large number of chlamydospores for survival. [ABSTRACT FROM AUTHOR]

ABSTRACT Arthrobotrys flagrans (Duddingtonia flagrans) is a typical nematode-trapping fungus which has been used for nematode biocontrol. The global regulator LaeA is widely distributed in filamentous fungi and plays a crucial role in secondary metabolism and development in addition to pathogenicity in fungal pathogens. In this study, the chromosome-level genome of A. flagrans CBS 565.50 was sequenced and homologous sequences of LaeA were identified in A. flagrans. A. flagrans LaeA (AfLaeA) knockout resulted in slower hyphal growth and a smoother hyphal surface. Importantly, deletion of AfLaeA resulted in the absence of chlamydospores and attenuated glycogen and lipid accumulation in hyphae. Similarly, disruption of the AfLaeA gene led to fewer traps and electron-dense bodies, lower protease activity, and a delay in capturing nematodes. The AfLaeA gene had a large effect on the secondary metabolism of A. flagrans, and both the deletion and overexpression of AfLaeA could yield new compounds, whereas some compounds were lost due to the absence of the AfLaeA. Protein-protein interactions between AfLaeA and another eight proteins were detected. Furthermore, transcriptome data analysis showed that 17.77% and 35.51% of the genes were influenced by the AfLaeA gene on days 3 and 7, respectively. AfLaeA gene deletion resulted in the higher expression level of the artA gene cluster, and multiple differentially expressed genes involved in glycogen and lipid synthesis and metabolism showed opposite expression patterns in wild-type and ΔAfLaeA strains. In summary, our results provide novel insights into the functions of AfLaeA in mycelial growth, chlamydospore production, pathogenicity, secondary metabolism, and energy metabolism in A. flagrans. IMPORTANCE The regulation of biological functions, such as the secondary metabolism, development, and pathogenicity of LaeA, has been reported in multiple fungi. But to date, no study on LaeA in nematode-trapping fungi has been reported. Moreover, it has not been investigated whether or not LaeA is involved in energy metabolism and chlamydospore formation has not been investigated. Especially in the formation mechanism of chlamydospores, several transcription factors and signaling pathways are involved in the production of chlamydospores, but the mechanism of chlamydospore formation from an epigenetic perspective has not been revealed. Concurrently, an understanding of protein-protein interactions will provide a broader perspective on the regulatory mechanism of AfLaeA in A. flagrans. This finding is critical for understanding the regulatory role of AfLaeA in the biocontrol fungus A. flagrans and establishes a foundation for developing high-efficiency nematode biocontrol agents.

Candidiasis now represents the fourth most frequent nosocomial infection both in the USA and worldwide. Candida albicans is an increasingly common threat to human health as a consequence of AIDS, steroid therapy, organ and tissue transplantation, cancer therapy, broad-spectrum antibiotics, and other immune defects. Unfortunately, these infections carry unacceptably high morbidity, mortality rates and important economic repercussions (estimated total direct cost of approximately 2 billion dollars in 1998 in US hospitals alone). This pathogen can grow both in yeast and filamentous forms and the pathogenic potential of C. albicans is intimately related to certain key processes including filamentation. Chlamydospores are considered to be a dormant form of C. albicans that remain understudied. Chlamydospores have been widely used as a diagnostic tool to separate C. albicans and C. dubliniensis from other Candida species. More recently, media have been developed that use chlamydopsore formation to separate C. albicans and C. dubliniensis from each other. Chlamydospore formation can be stimulated by hypoxic conditions but only on limited specific media types. Here, we show that anaerobic conditions are enough to drive chlamydospore formation in C. albicans on the surface of nutrient-rich agar. [ABSTRACT FROM AUTHOR]

Global banana production is affected by Fusarium wilt, a devastating disease caused by the soilborne root‐infecting fungus, Fusarium oxysporum f. sp. cubense (Foc). Fusarium wilt is notoriously difficult to manage because infection arises through complex below‐ground interactions between Foc, the plant, and the soil microbiome in the root–soil interface, defined as the rhizosphere. Interactions in the rhizosphere play a pivotal role in processes associated with pathogen development and plant health. Modulation of these processes through manipulation and management of the banana rhizosphere provides an auspicious prospect for management of Fusarium wilt. Yet, a fundamental understanding of interactions in the banana rhizosphere is still lacking. The objective of this review is to discuss the state‐of‐the‐art of the relatively scant data available on banana below‐ground interactions in relation to Fusarium wilt and, as a result, to highlight key research gaps. Specifically, we seek to understand (a) the biology of Foc and its interaction with banana; (b) the ecology of Foc, including the role of root‐exuded metabolites in rhizosphere interactions; and (c) soil management practices and how they modulate Fusarium wilt. A better understanding of molecular and ecological factors influencing banana below‐ground interactions has implications for the development of targeted interventions in the management of Fusarium wilt through manipulation of the banana rhizosphere. [ABSTRACT FROM AUTHOR]

Abstract Autophagy is an evolutionarily conserved degradation process that degrades damaged proteins to maintain homeostasis and to protect cells against stress. In this study, we identified and characterized a critical autophagy-related protein, UvAtg14, in Ustilaginoidea virens, which is the ortholog of MoAtg14 in rice blast fungus Magnaporthe oryzea. UvAtg14 is co-localized with UvAtg8 (an autophagy marker protein) and is highly expressed at 1–3 days post-inoculation. Deletion of the UvATG14 gene blocked GFP-UvAtg8 trafficking and autophagic digestion and significantly reduced mycelial growth, asexual reproduction, and virulence of U. virens. UvATG14 deletion mutants also exhibited increased sensitivity to various abiotic stresses. Our findings indicate that UvAtg14 is a key autophagic protein and contributes to mycelial growth, conidia production, and pathogenicity in U. virens.

Trichoderma strains have been successfully used in plant disease control. However, the poor stress resistance of mycelia and conidia makes processing and storage difficult. Furthermore, they cannot produce chlamydospores in large quantities during fermentation, which limits the industrialization process of chlamydospore preparation. It is important to explore an efficient liquid fermentation strategy for ensuring chlamydospore production in Trichoderma harzianum. We found that the addition of mannitol, glycine betaine, and N-acetylglucosamine (N-A-G) during liquid fermentation effectively increases the yield of chlamydospores. Furthermore, we provided evidence that chlamydospores have stronger tolerance to high temperature, ultraviolet, and hypertonic stress after the addition of mannitol and trehalose. Lipids are an important component of microbial cells and impact the stress resistance of microorganisms. We studied the internal relationship between lipid metabolism and the stress resistance of chlamydospores by detecting changes in the lipid content and gene expression. Our results showed that mannitol and trehalose cause lipid accumulation in chlamydospores and increase the unsaturated fatty acid content. In conclusion, we verified that these exogenous regulators increase the production of chlamydospores and enhance their stress resistance by regulating lipid metabolism. In addition, we believe that lipid metabolism is an important part of the chlamydospore production process and impacts the stress resistance of chlamydospores. Our findings provide clues for studying the differentiation pathway of chlamydospores in filamentous fungi and a basis for the industrial production of chlamydospores. [ABSTRACT FROM AUTHOR]

Trichoderma strains have been successfully used in plant disease control. However, the poor stress resistance of mycelia and conidia makes processing and storage difficult. Furthermore, they cannot produce chlamydospores in large quantities during fermentation, which limits the industrialization process of chlamydospore preparation. It is important to explore an efficient liquid fermentation strategy for ensuring chlamydospore production in Trichoderma harzianum. We found that the addition of mannitol, glycine betaine, and N-acetylglucosamine (N-A-G) during liquid fermentation effectively increases the yield of chlamydospores. Furthermore, we provided evidence that chlamydospores have stronger tolerance to high temperature, ultraviolet, and hypertonic stress after the addition of mannitol and trehalose. Lipids are an important component of microbial cells and impact the stress resistance of microorganisms. We studied the internal relationship between lipid metabolism and the stress resistance of chlamydospores by detecting changes in the lipid content and gene expression. Our results showed that mannitol and trehalose cause lipid accumulation in chlamydospores and increase the unsaturated fatty acid content. In conclusion, we verified that these exogenous regulators increase the production of chlamydospores and enhance their stress resistance by regulating lipid metabolism. In addition, we believe that lipid metabolism is an important part of the chlamydospore production process and impacts the stress resistance of chlamydospores. Our findings provide clues for studying the differentiation pathway of chlamydospores in filamentous fungi and a basis for the industrial production of chlamydospores.

Rice false smut caused by Villosiclava virens is a devastating disease. The smut balls contain chlamydospores, which fall onto paddy soils to become the primary inoculum. After transplanting, the chlamydospores subsequently germinate and infect rice roots. The application of a CaO‐containing fertilizer to paddy soils can inhibit the development of rice false smut disease; however, the underlying mechanism is unknown. In this study, we evaluated the suppression of chlamydospore behaviour due to CaO. Specifically, we clarified the effects of the following on chlamydospore morphology and germination: (a) pH, (b) calcium (Ca) concentration, (c) Ca concentration (pH adjusted to 6.5), and (d) CaO‐added soil solution. Germination was suppressed at pH 4 and 10, in contrast with the normal germination at pH 6, 7, and 8. Treatments with more than 10 mg/L Ca melted the outer layer of chlamydospores and suppressed germination regardless of whether the pH was adjusted to 6.5. A saturated CaO solution induced bursting of chlamydospores. Suppressed germination and a melted outer chlamydospore layer were also observed, even though the soil buffering effect initially prevented the CaO‐mediated pH increase. Furthermore, the chlamydospores within 15 mm from the CaO small lump exhibited suppressed germination in soil. In addition, there was no effect of CaO treatment on chlamydospore attachment to rice roots and hyphal invasion of rice roots in in vitro inoculation tests. These results suggest that Ca concentration is an important factor for inhibiting the occurrence of rice false smut disease. [ABSTRACT FROM AUTHOR]

Abstract Background During current submerged fermentation for microbial lipid production, the large-scale reactor operations inevitably consume substantial amounts of water and electricity for aeration, stirring, and temperature control and result in the operational costs almost exceeding the biodiesel value produced. Thus, developing a novel low-cost cultivation strategy is urgently needed by microbial lipid industry. Results The filamentous fungus Phanerochaete chrysosporium can synthesize and accumulate lipids via static solid cultivation. The conversion efficiency of substrates to lipids reaches 0.277 g/g substrate after optimization of the following cultivation factors: humidity, solid medium thickness, temperature, and rotary speed. The lipids obtained by static solid cultivation differ in component and relative content from those achieved by submerged cultivation. Laser scanning confocal microscopy reveals that numerous chlamydospores filled with lipids appear during static solid cultivation, and the fungal morphological change explains why static solid cultivation is superior in lipid yield compared with submerged fermentation. The genes coding the enzymes related to fatty acid elongation and degradation are differently expressed during static solid cultivation, which presents an answer to the appearance of abundant saturated long-chain fatty acids (93.6% in total fatty acids) in chlamydospores. In addition, engineering viability and cost–benefit analysis show that the conversion of wheat bran and glucose to lipid by the fungus is efficient. More importantly, the solid cultivation incurs only a small reactor operational cost because neither cooling water nor electrical equipment, including aerator, stirrer, and the temperature control system, is used. Conclusions This study developed a robust and cost-saving solid fermentation method without an aerator, stirrer, and temperature control system to produce microbial lipids using the chlamydospores of P. chrysosporium. Compared with conventional submerged fermentation, the solid cultivation strategy is promising because it diminishes most of the reactor operational costs, including water and power expenses.

Phanerochaete chrysosporium is a white rot fungus naturally isolated from hardwoods and widely used in environmental pollution control because it produces extracellular peroxidases. It forms chlamydospores during nitrogen starvation, which naturally occurs in the habitat of P. chrysosporium. Chlamydospores protect fungi against many stresses; the molecular basis underlying chlamydospore formation in basidiomycetes is poorly explored. Chlamydospores in P. chrysosporium have a different cell wall compared with hyphae, as confirmed by cell wall digestion and microscopy. Furthermore, this study investigated the transcriptome of P. chrysosporium in different life stages, including conidium, hypha, and chlamydospore formation, through RNA sequencing. A total of 2215 differentially expressed genes were identified during these processes. The expression patterns of genes involved in several molecular events critical for chlamydospore formation, including starch and sucrose metabolism, phosphatase and kinase, and transcription factors, were determined. This study serves as a basis for further investigating the function of chlamydospore formation in the biotechnologically relevant fungus P. chrysosporium.

Phytophthora infestans causes late blight of potato and tomato. In this study, two distinct groups of P. infestans isolates are reported based on morphological and molecular characters. The isolates were recovered from 300 single lesion leaf samples collected from potato in western and southern Ethiopia. The pathogen DNA was isolated from the single lesion dry leaves while live cultures were isolated from actively growing lesions of 100 leaves. Mitochondrial DNA (mtDNA) analysis clearly separated the isolates into two distinct groups. One of the groups corresponds to a known P. infestans mtDNA haplotype but the other is unique with a distinct Ic mtDNA haplotype and atypical morphological characters. DNA sequencing of the mtDNA confirmed that the isolates represented a previously unknown variant of P. infestans attacking Solanum tuberosum. In addition, the Ic mtDNA haplotype isolates produced papillate sporangia and chlamydospores that distinguished them from typical P. infestans isolates. All examined isolates were heterothalic and compatibility mating type A1. The novel group of the Ic mtDNA isolates constituted a single clonal population that had identical DNA fingerprint with a dominant lineage of the Ia mtDNA haplotype of P. infestans across nine microsatellite markers. This study provided new insight into a previously unknown variability within P. infestans in a region of the world where the pathogen population has rarely been studied. Further work is needed to understand the origins and significance of this finding.

The banana is one of Colombia's main export products. However, production is seriously affected by Fusarium wilt of banana, which is the most destructive disease caused by the fungus Fusarium oxysporum f. sp. cubense tropical race 4 ( Foc TR4). Currently, management strategies focus on containment and biosecurity protocols to prevent its spread to territories that are free of this disease. This study aimed to evaluate nine quaternary ammonium-based disinfectants (i.e., quaternary ammonium compounds [QACs]) in vitro in Colombia on reproductive (microconidia and macroconidia) and resistance structures (chlamydospores) of Foc race 1 (R1) and tropical race 4 (TR4), with and without soil, to determine the influence of organic matter and soil texture on the action of QACs. A method for inhibiting the action of QACs was standardized and evaluated at 1,200 ppm with a contact time of ≤30 s while evaluating the soil-inoculum and soil-disinfectant interactions. In the soil-inoculum interaction, the efficacy of QACs was 100% in the reproductive and resistance structures of Foc R1 and TR4 without soil. However, in the soil-disinfectant interaction, only QAC4 controlled the pathogen at 100%. The presence of organic matter influenced the biocidal action of the QACs, and fine textures had a greater reducing effect on the concentration. The soil decreased the efficacy of the QACs and, therefore, must be removed from contaminated boots before treatments are applied., Competing Interests: The author(s) declare no conflict of interest.

Phanerochaete chrysosporium is a white rot fungus naturally isolated from hardwoods and widely used in environmental pollution control because it produces extracellular peroxidases. It forms chlamydospores during nitrogen starvation, which naturally occurs in the habitat of P. chrysosporium. Chlamydospores protect fungi against many stresses; the molecular basis underlying chlamydospore formation in basidiomycetes is poorly explored. Chlamydospores in P. chrysosporium have a different cell wall compared with hyphae, as confirmed by cell wall digestion and microscopy. Furthermore, this study investigated the transcriptome of P. chrysosporium in different life stages, including conidium, hypha, and chlamydospore formation, through RNA sequencing. A total of 2215 differentially expressed genes were identified during these processes. The expression patterns of genes involved in several molecular events critical for chlamydospore formation, including starch and sucrose metabolism, phosphatase and kinase, and transcription factors, were determined. This study serves as a basis for further investigating the function of chlamydospore formation in the biotechnologically relevant fungus P. chrysosporium. [ABSTRACT FROM AUTHOR]

The success of Candida albicans as a pathogen relies on its ability to adapt and proliferate in different environmental niches. Pathways regulated by mitogen-activated protein kinases (MAPKs) are involved in sensing environmental conditions and developing an accurate adaptive response. Given the frequent cooperative roles of these routes in cellular functions, we have generated mutants defective in all combinations of the four described MAPKs in C. albicans and characterized its phenotype regarding sensitiveness to specific drugs, morphogenesis and interaction with host immune cells. We demonstrate that all MAPKs are dispensable in this yeast as a mutant defective in Cek1, Cek2, Mkc1 and Hog1 is viable although highly sensitive to oxidative and osmotic stress, displaying a specific pattern of sensitivity to antifungals. By comparing its phenotype with single, double and triple combinations of MAPK-deletion mutants we were able to unveil a Cek1-independent mechanism for Hog1 resistance to Congo red, and confirm the predominant effect of Hog1 on oxidative and osmotic adaptation. The quadruple mutant produces filaments under non-inducing conditions, but is unable to develop chlamydospores. Furthermore, cek1 cek2 mkc1 hog1 cells switch to the opaque state at high frequency, which is blocked by the ectopic expression of HOG1 suggesting a role of this kinase for phenotypic switching. [ABSTRACT FROM AUTHOR]

Sparassis latifolia is a valuable edible fungus cultivated in East Asia that is rich in β-glucans. Understanding the mating system and sexual life cycle is important not only for breeding programs to improve strains but also for studies on speciation and population structures. In the present study, mating experiments using monokaryons derived from two different parental strains were performed. Chi-squared test indicated satisfied Mendel segregation, which supported a tetrapolar mating system. A search in the genome for homologs to the well-defined homeodomain and pheromone/receptors, as well as frequently found flanking genes, resulted in the identification of known mating-type loci previously identified in tetrapolar basidiomycetes, each represented by two idiomorphic alleles on separate contigs. Deficiency of the β-flanking protein in S. latifolia and S. crispa around the MAT-A locus may be explained by the locus being rich in transposable elements adjacent to HD genes. Monokaryotic mycelia are characterized by a slower growth rate and a relative lack of aerial mycelia compared with the parental strain. Chlamydospores can be produced in both monokaryotic and dikaryotic mycelial stages. We provide genetic and molecular evidence for the mating system of S. latifolia , a finding that will be helpful for the cross-breeding of this mushroom. • Both genetic and molecular evidence supports the tetrapolar system of Sparassis latifolia. • β-Flanking protein is absent around the MAT-A locus in S. latifolia and Sparassis crispa. • Three transposable elements are adjacent to HD genes in S. latifolia and S. crispa. [ABSTRACT FROM AUTHOR]

Fusarium wilt of tomato caused by the ascomycetous fungus Fusarium oxysporum f. sp. lycopersici (Fol) is widespread in most tomato planting areas. Calcineurin is a heterodimeric calcium/calmodulin-dependent protein phosphatase comprised of catalytic (Cna1) and regulatory (Cnb1) subunits. Calcineurin has been studied extensively in human fungal pathogens, but less is known about its roles in plant fungal pathogens. It is known that calcineurin regulates fungal calcium signaling, growth, drug tolerance, and virulence. However, the roles of calcineurin in Fol have not yet been characterized. In this study, we deleted calcineurin CNA1 and CNB1 genes to characterize their roles in conidiation, chlamydospore formation and virulence in Fol. Our results revealed that both cna1 and cnb1 mutants show defects in calcineurin phosphatase activity, vegetative growth and conidiation as compared to the wild type. Furthermore, calcineurin mutants exhibited blunted and swollen hyphae as observed by scanning electron microscopy. Interestingly, we found that Fol calcineurin is critical for chlamydospore formation, a function of calcineurin previously undocumented in the fungal kingdom. According to transcriptome analysis, the expression of 323 and 414 genes was up- and down-regulated, respectively, in both cna1 and cnb1 mutants. Based on the pathogen infection assay, tomato plants inoculated with cna1 or cnb1 mutant have a dramatic reduction in disease severity, indicating that calcineurin has a vital role in Fol virulence. In conclusion, our findings suggest that Fol calcineurin is required, at least in part, for phosphatase activity, vegetative growth, conidiation, chlamydospore formation, and virulence.

Fusarium wilt of tomato caused by the ascomycetous fungus Fusarium oxysporum f. sp. lycopersici (Fol) is widespread in most tomato planting areas. Calcineurin is a heterodimeric calcium/calmodulin-dependent protein phosphatase comprised of catalytic (Cna1) and regulatory (Cnb1) subunits. Calcineurin has been studied extensively in human fungal pathogens, but less is known about its roles in plant fungal pathogens. It is known that calcineurin regulates fungal calcium signaling, growth, drug tolerance, and virulence. However, the roles of calcineurin in Fol have not yet been characterized. In this study, we deleted calcineurin CNA1 and CNB1 genes to characterize their roles in conidiation, chlamydospore formation and virulence in Fol. Our results revealed that both cna1 and cnb1 mutants show defects in calcineurin phosphatase activity, vegetative growth and conidiation as compared to the wild type. Furthermore, calcineurin mutants exhibited blunted and swollen hyphae as observed by scanning electron microscopy. Interestingly, we found that Fol calcineurin is critical for chlamydospore formation, a function of calcineurin previously undocumented in the fungal kingdom. According to transcriptome analysis, the expression of 323 and 414 genes was up- and down-regulated, respectively, in both cna1 and cnb1 mutants. Based on the pathogen infection assay, tomato plants inoculated with cna1 or cnb1 mutant have a dramatic reduction in disease severity, indicating that calcineurin has a vital role in Fol virulence. In conclusion, our findings suggest that Fol calcineurin is required, at least in part, for phosphatase activity, vegetative growth, conidiation, chlamydospore formation, and virulence. [ABSTRACT FROM AUTHOR]

Species of Endogonaceae (Endogonales, Mucoromycotina) are characterized by the formation of relatively large sporocarps and zygosporangia. Numerous species in this family remain undescribed or have unclear phylogenetic positions. In Asia specifically, the species diversity of this family is almost completely unknown. However, many mycobionts of bryophytes belonging to several novel clades in Endogonaceae have recently been identified phylogenetically. Therefore, establishing a robust taxonomic system for this family is essential. We obtained numerous sporocarps of undescribed Endogonaceae-like species from the Japanese islands. Morphological observation and multilocus phylogenetic analysis of nuc 18S rDNA (18S), nuc 28S rDNA (28S), and portions of two nuclear protein-coding regions—translation elongation factor 1-alpha (tef1) and RNA polymerase II large subunit (rpb1)—from these species resulted in the description of one new species each of Endogone and Jimgerdemannia and two new species of Vinositunica, gen. nov. Because Vinositunica is characterized by purplish sporocarps and red-wine-colored chlamydospores up to 700 μm in diameter, we emended the definition of Endogonaceae. [ABSTRACT FROM AUTHOR]

In order to develop a simple method for crossing two transformants, we first attempted to elucidate the fusion type (self-compatibility or -incompatible) of Phanerochaete sordida YK-624. Two transformants expressing green or red fluorescent protein derived from an auxotrophic mutant were constructed. Each recombinant protein fluoresced by expression as a fused protein with glyceraldehyde-3-phosphate dehydrogenase. On co-culture of both transformants, a number of sequential hyphal cells emitting dual fluorescence were formed at the contact areas of both hyphae. Some of the single cells isolated as protoplasts and chlamydospore from the co-cultures also expressed these fluorescent proteins. These results suggest that P. sordida YK-624 possesses a self-compatible fusion system. In addition, transformant strains with different fluorescence derived from this fungus can readily undergo self-fusion and nuclear interchange events by confrontational and mixed cultivation, and we developed a simple method that allows fused cells to be isolated as chlamydospores. [ABSTRACT FROM AUTHOR]

Bioversity of fungal antagonist, Trichoderma from different locations of Nilgiri district of Tamil Nadu, India, were characterized through molecular methods. Thirty four isolates were tentatively identified as Trichoderma and confirmed upto species level through molecular tools. PCR amplification of the 18s-28s rRNA gene region revealed that all thirty four isolates produced amplicon size of 600bp and were further confirmed through sequencing. The sequences of various Trichoderma spp. were compared with both NCBI and TrichOKEY database to validate their molecular identity. Among 34 isolates, 31 isolates were identified as T. asperellum (KT462693, KU361372, KX533978 to KX533999, KX523262 to KX523264, KX555650, KX147092 to KX147094, KX5334000), 2 isolates as T. harzianum (KX533989, KX533990) and 1 isolate as T. virens (KU666466) through NCBI data base. However, all the T. asperellum isolates identified through NCBI database were identified as T. koningiopsis using TricHOKEY data base. Identity of T. harzianum isolates (TRI 35 and TRI 36) and T. virens isolate (TRI 37) were same in both NCBI and TricHOKEY database. Antagonistic assay with diverse species of Trichoderma revealed that T. virens (TRI 37) was effective in inhibiting the radial growth of Pythium aphanidermatum (87.78%) followed by T. harzianum (TRI 35), (TRI 36) and T. asperellum (TRI 9) in vitro. The effective isolates T. virens (TRI 37), T. harzianum (TRI 35, TRI 36) and T. asperellum (TRI 9) were compatible with each other. Biopriming of cucumber seeds with talc based formulation of the consortia comprising of T. virens isolate ( TRI 37), T. harzianum isolates (TRI 35 and TRI 36) and T. asperellum TRI 9 @ 108 cfu/g and soil application suppressed damping off to an extent of 76.82% over untreated control.

Rice false smut fungus (teleomorph: Villosiclava virens; anamorph: Ustilaginoidea virens) can generate chlamydospores and survive winter under field conditions. The chlamydospore is considered as an important infection source of the disease. However, little is known about the regulatory mechanism of the chlamydospore production. In this study, we identified a defective homeobox transcription factor (designated as UvHOX2) gene in a U. virens random insertional mutant B-766 that could not form chlamydospores. To confirm the regulatory function of UvHOX2, an Agrobacterium tumefaciens mediated transformation- and CRISPR/Cas9- based targeted gene replacement method was developed. The UvHox2 deletion mutants completely failed to produce chlamydospores, showed reduced conidia production and decreased virulence, and was hyper-sensitive to oxidative, osmotic, and cell wall stresses. We confirmed that UvHOX2 is located in the nuclei of U. virens, and the expression of UvHox2 was the strongest during the early stage of chlamydospore and conidium formation. Global transcription pattern of UvHOX2 was also determined by RNA-seq in this study, and several genes that might be down-stream of UvHOX2 regulation were identified. The results will better our understanding of the molecular mechanism of chlamydospore formation in U. virens as a model fungus.

Rice false smut fungus (teleomorph: Villosiclava virens ; anamorph: Ustilaginoidea virens) can generate chlamydospores and survive winter under field conditions. The chlamydospore is considered as an important infection source of the disease. However, little is known about the regulatory mechanism of the chlamydospore production. In this study, we identified a defective homeobox transcription factor (designated as UvHOX2) gene in a U. virens random insertional mutant B-766 that could not form chlamydospores. To confirm the regulatory function of UvHOX2, an Agrobacterium tumefaciens mediated transformation- and CRISPR/Cas9- based targeted gene replacement method was developed. The UvHox2 deletion mutants completely failed to produce chlamydospores, showed reduced conidia production and decreased virulence, and was hyper-sensitive to oxidative, osmotic, and cell wall stresses. We confirmed that UvHOX2 is located in the nuclei of U. virens , and the expression of UvHox2 was the strongest during the early stage of chlamydospore and conidium formation. Global transcription pattern of UvHOX2 was also determined by RNA-seq in this study, and several genes that might be down-stream of UvHOX2 regulation were identified. The results will better our understanding of the molecular mechanism of chlamydospore formation in U. virens as a model fungus. [ABSTRACT FROM AUTHOR]

Context: Candida, leukoplakia and oral squamous cell carcinoma. Aims: The aim of the present study has assessed the association of Candida albicans with normal control group, leukoplakia and oral squamous cell carcinoma lesions of the oral cavity by using cornmeal broth +5% milk and milk serum liquid culture media. Settings and Design: Thepresent study comprised of total 80 patients,which included, 30 patients of Leukoplakia, 30 patients of oral squamous cell carcinoma and normal control group comprised of 20 healthy individuals who were not having any relevant medical, dental and habit history. Subjects and Methods: Saliva and Biopsy was taken from clinically suspected leukoplakia and oral squamous cell carcinoma lesions for the confirmation of histopathological diagnosis. Saliva samples were inoculated for fungal growth in Sabouraud Dextrose Agar, and culture-positive samples had undergone for the germ tube test. Germ tube-positive samples were further taken for chlamydospore production in milk serum and cornmeal broth +5% milk media separately at 8 and 16 h. Statistical Analysis Used: Chi-square test, Fischer extract test. Results: In the normal control group, no fungus growth was found; however, leukoplakia and oral squamous cell carcinoma showed fungus growth with positive germ tube test and chlamydospore formation; the result also showed rapid and quantitatively more chlamydospore formation in cornmeal broth +5% milk in comparison to serum milk culture media. There was no growth of Candida in mild and moderate form of leukoplakia. Whereas in a severe form of leukoplakia, there was more quantitative chlamydospore growth in cornmeal broth +5% milk liquid media. Conclusions: In this study, we have tried to compare the efficacy of cornmeal broth +5% milk and milk serum for the identification of C. albicans. Both the culture media were able to promote the growth of chlamydospore in C. albicans. Among different grades of leukoplakia, the growth of C. albicans was seen in severe dysplastic patient only while mild and moderate dysplasia showed no Candidal growth. [ABSTRACT FROM AUTHOR]

The success of Candida albicans as a pathogen relies on its ability to adapt and proliferate in different environmental niches. Pathways regulated by mitogen-activated protein kinases (MAPKs) are involved in sensing environmental conditions and developing an accurate adaptive response. Given the frequent cooperative roles of these routes in cellular functions, we have generated mutants defective in all combinations of the four described MAPKs in C. albicans and characterized its phenotype regarding sensitiveness to specific drugs, morphogenesis and interaction with host immune cells. We demonstrate that all MAPKs are dispensable in this yeast as a mutant defective in Cek1, Cek2, Mkc1 and Hog1 is viable although highly sensitive to oxidative and osmotic stress, displaying a specific pattern of sensitivity to antifungals. By comparing its phenotype with single, double and triple combinations of MAPK-deletion mutants we were able to unveil a Cek1-independent mechanism for Hog1 resistance to Congo red, and confirm the predominant effect of Hog1 on oxidative and osmotic adaptation. The quadruple mutant produces filaments under non-inducing conditions, but is unable to develop chlamydospores. Furthermore, cek1 cek2 mkc1 hog1 cells switch to the opaque state at high frequency, which is blocked by the ectopic expression of HOG1 suggesting a role of this kinase for phenotypic switching.

Arthrobotrys flagrans ( Duddingtonia flagrans ) is a typical nematode-trapping fungus which has been used for nematode biocontrol. The global regulator LaeA is widely distributed in filamentous fungi and plays a crucial role in secondary metabolism and development in addition to pathogenicity in fungal pathogens. In this study, the chromosome-level genome of A. flagrans CBS 565.50 was sequenced and homologous sequences of LaeA were identified in A. flagrans . A. flagrans LaeA ( AfLaeA ) knockout resulted in slower hyphal growth and a smoother hyphal surface. Importantly, deletion of AfLaeA resulted in the absence of chlamydospores and attenuated glycogen and lipid accumulation in hyphae. Similarly, disruption of the AfLaeA gene led to fewer traps and electron-dense bodies, lower protease activity, and a delay in capturing nematodes. The AfLaeA gene had a large effect on the secondary metabolism of A. flagrans , and both the deletion and overexpression of AfLaeA could yield new compounds, whereas some compounds were lost due to the absence of the AfLaeA . Protein-protein interactions between AfLaeA and another eight proteins were detected. Furthermore, transcriptome data analysis showed that 17.77% and 35.51% of the genes were influenced by the AfLaeA gene on days 3 and 7, respectively. AfLaeA gene deletion resulted in the higher expression level of the artA gene cluster, and multiple differentially expressed genes involved in glycogen and lipid synthesis and metabolism showed opposite expression patterns in wild-type and Δ AfLaeA strains. In summary, our results provide novel insights into the functions of AfLaeA in mycelial growth, chlamydospore production, pathogenicity, secondary metabolism, and energy metabolism in A. flagrans . IMPORTANCE The regulation of biological functions, such as the secondary metabolism, development, and pathogenicity of LaeA, has been reported in multiple fungi. But to date, no study on LaeA in nematode-trapping fungi has been reported. Moreover, it has not been investigated whether or not LaeA is involved in energy metabolism and chlamydospore formation has not been investigated. Especially in the formation mechanism of chlamydospores, several transcription factors and signaling pathways are involved in the production of chlamydospores, but the mechanism of chlamydospore formation from an epigenetic perspective has not been revealed. Concurrently, an understanding of protein-protein interactions will provide a broader perspective on the regulatory mechanism of AfLaeA in A. flagrans . This finding is critical for understanding the regulatory role of AfLaeA in the biocontrol fungus A. flagrans and establishes a foundation for developing high-efficiency nematode biocontrol agents., Competing Interests: The authors declare no conflict of interest.

Various types of other fungi colonize glomeromycotinan (Mucoromycota) spores in the Early Devonian Rhynie chert. However, relatively few of these associations have been described and evaluated in detail. One particular type of glomoid spore located in degrading land plant axes from the Rhynie chert provides evidence of (simultaneous) interaction with three different fungi. Massive callosities occur around the intrusion filaments of a chytrid-like parasite with epibiotic sporangia, while the hyphae of a delicate mycelial fungus extend into the spore lumen without triggering a recognizable host response. Several spores show large numbers of inwardly directed projections, which are regularly distributed and consist of a short hyphal branch encased in host wall material. The projections represent the penetration sites of a distinctive, mycelial fungus that forms a mantle-like hyphal sheath around the spores. This type of fungal interaction with glomeromycotinan spores has not previously been reported, and thus expands our knowledge of the numerous interfungal relationships that existed in early continental ecosystems. [ABSTRACT FROM AUTHOR]

Bioversity of fungal antagonist, Trichoderma from different locations of Nilgiri district of Tamil Nadu, India, were characterized through molecular methods. Thirty four isolates were tentatively identified as Trichoderma and confirmed upto species level through molecular tools. PCR amplification of the 18s-28s rRNA gene region revealed that all thirty four isolates produced amplicon size of 600bp and were further confirmed through sequencing. The sequences of various Trichoderma spp. were compared with both NCBI and TrichOKEY database to validate their molecular identity. Among 34 isolates, 31 isolates were identified as T. asperellum (KT462693, KU361372, KX533978 to KX533999, KX523262 to KX523264, KX555650, KX147092 to KX147094, KX5334000), 2 isolates as T. harzianum (KX533989, KX533990) and 1 isolate as T. virens (KU666466) through NCBI data base. However, all the T. asperellum isolates identified through NCBI database were identified as T. koningiopsis using TricHOKEY data base. Identity of T. harzianum isolates (TRI 35 and TRI 36) and T. virens isolate (TRI 37) were same in both NCBI and TricHOKEY database. Antagonistic assay with diverse species of Trichoderma revealed that T. virens (TRI 37) was effective in inhibiting the radial growth of Pythium aphanidermatum (87.78%) followed by T. harzianum (TRI 35), (TRI 36) and T. asperellum (TRI 9) in vitro. The effective isolates T. virens (TRI 37), T. harzianum (TRI 35, TRI 36) and T. asperellum (TRI 9) were compatible with each other. Biopriming of cucumber seeds with talc based formulation of the consortia comprising of T. virens isolate ( TRI 37), T. harzianum isolates (TRI 35 and TRI 36) and T. asperellum TRI 9 @ 108 cfu/g and soil application suppressed damping off to an extent of 76.82% over untreated control. [ABSTRACT FROM AUTHOR]

Background and Objective: The present study evaluates the association of Candida albicans with normal control group, potentially malignant and malignant lesions of oral cavity by using two different liquid culture media. Materials and Methods: Saliva was collected and biopsy was taken only from those clinically suspected potentially malignant and malignant lesions for histopathological diagnosis. Saliva samples were inoculated for fungal growth in Sabouraud′s dextrose agar and culture-positive samples had undergone for Germ tube test. Germ tube-positive samples were further taken for quantification of chlamydospore production in liquid media at 8 and 16 hours. Results: In normal control groups no fungus growth was found; however, potentially malignant and malignant cases showed fungus growth, positive germ tube test and chlamydospore formation. The result also showed rapid and quantitatively more chlamydospore formation in corn meal broth + 5% milk in comparison to serum milk culture media. Conclusion: The oral mucosa is compromised in potentially malignant lesions, it can be argued that this species may be involved in carcinogenesis by elaborating the nitrosamine compounds which either act directly on oral mucosa or interact with other chemical carcinogens to activate specific proto-oncogenes and thereby initiate oral neoplasia.

This study builds on previous investigations of paleomycological diversity within permineralized plants of a significant Eocene paleobotanical locality, the Princeton Chert. The fungal body fossils described here occur in decayed rhizomes of the extinct semi-aquatic fern Dennstaedtiopsis aerenchymata. Fungi include vegetative hyphae throughout the plant tissue, as well as a dense assemblage of .100 dematiaceous spores. The spores occur in a discrete zone surrounding two extraneous rootlets of other plants, which penetrated the fern tissue post-mortem. Spores are obovoid and muriform, composed of 8-12 cells with constricted septa and produced from hyaline or slightly pigmented hyphae. The spores are morphologically similar to both asexual reproductive dictyospores of phylogenetically disparate microfungi attributed to the morphogenus Monodictys and perennating dictyochlamydospores that occur in the anamorph genus Phoma. In addition to expanding the early Eocene fossil record for Ascomycota, these specimens also provide new insight into the rapidity of initial phases of the fossilization process in this important paleobotanical locality. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Zhejiang University: Science B is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A total of 9 strains consisting of both V. volvacea (5 cultivated strains viz., CBE TNAU 1401 to 1405; 2 wild strains viz., CBE TNAU 1505 and 1516) and V. bombycina (one cultivated strain CBE TNAU 1406 and one wild strain CBE TNAU 1504) were evaluated to ascertain the variation in their morphological, cultural and molecular characters. Among strains tested, CBE TNAU 1505 was the best strain, which showed earliness in spawn run, more biomass production in unit time and more chlamydospores production with high density. In the trials conducted with partially decomposed paddy straw, the highest yield of 1041.2 g per 5 kg of substrate with an average biological efficiency of 20.8 per cent was recorded with CBE TNAU 1505. Molecular detection of Volvariella strains through 5.8S rDNA regions showed that ITS primers had amplified a product size between 700 and 740 bp. RAPD - PCR phylogenetic analyses revealed 2 major clusters. V. volvacea strains showed approximately 13 per cent genetic similarities with the strains of V. bombycina. [ABSTRACT FROM AUTHOR]

Ustilaginoidea virens is the causal agent of a serious disease of rice. To reveal the relationship between germination and the 3'-5'-cyclic adenosine monophosphate (cAMP) content from the dormant (black or green-black) and non-dormant (yellow) chlamydospore in Ustiloginoidea virens,this study adopts ultrasonic-bath method and high-performance liquid chromatography (HPLC) method, for extraction cAMP content of the different color chlamydospore. The results demonstrated that, as for the freshly chlamydospores collected from the false smut balls during their germination, cAMP content of yellow chlamydospore appeared a slight growth during 0-12 h, and showed a rapid declining as the germination time extended (12-48 h) . Above all, in yellow chlamydospores, the germination rate and the content of cAMP presented a very notably negative correlation (|r|=0.861 9>r0.01=0.834), but the correlation between germination rate and content of cAMP was not obvious in black chlamydospores. The germination rate and the content of cAMP presented a notably positive correlation under different storage period (0, 2, 4, 6, 8, 10 months) of the two color chlamydospores (the yellow of chlamydospore: |r| = 0.785 1 > r0.05 = 0.707; the black of chlamy-dospore: |r| = 0.957 9 > r0.05 = 0.707). [ABSTRACT FROM AUTHOR]

Polymorphic yeast, Candida albicans, forms thick-walled structures called chlamydospores in order to survive under adverse conditions. We present proteomic profile changes occurring during chlamydospore formation. Chlamydospores were induced by inoculating C. albicans cells (grown for 48 h) on rice extract and semisolid agar containing tween 80 (1%), and were overlaid by a polyethene sheet to induce microaerophilic conditions at 30 °C. Proteins extracted from chlamydospores and hyphae (producing chlamydospores) were identified by LC-MS/MS analysis. Present datasets include proteomic data (Swath spectral libraries) of chlamydospores and yeast phase cells, as well as methodologies and tools used for the data generation. Further analysis is expected to provide an opportunity to understand modulations in metabolic processes, molecular architecture (i.e., cell wall, membrane, and cytoskeleton) and stress response pathways leading to chlamydospore formation and thus facilitating survival of C. albicans under adverse conditions.

A mycoparasite, Scytalidium parasiticum sp. nov., isolated from the basidiomata of Ganoderma boninense causing basal stem rot of oil palm in Johor, Malaysia, is described and illustrated. It is distinct from other Scytalidium species in having smaller asci and ascospores (teleomorphic stage), longer arthroconidia (anamorphic stage), hyaline to yellowish chlamydospores, and producing a fluorescent pigment. The phylogenetic position of S. parasiticum was determined by sequence analyses of the internal transcribed spacers and the small-subunit ribosomal RNA gene regions. A key to identify Scytalidium species with teleomorphic stage is provided. [ABSTRACT FROM AUTHOR]

Trichophyton tonsurans is known to be the causative agent of a worldwide epidemic of dermatophytoses among contact sports practitioners, and is spreading among the general population of Japan. Prompt and simple identification of T. tonsurans in diagnostic laboratories is crucial to control infection. The present study evaluated the availability of observation of chlamydospore-like structures grown in culture media as a characteristic for identification of T. tonsurans. Twenty-five strains of T. tonsurans and five strains each of Trichophyton verrucosum, Trichophyton rubrum and Trichophyton mentagrophytes were inoculated on Mycosel agar plates and inoculated Petri dishes were observed by light microscopy from the reverse side. Twenty-three of 25 T. tonsurans strains showed chlamydospore-like structures within 5 days, and all strains at day 8. The numbers of chlamydospore-like structures were very abundant in most strains. The majority of strains of other species showed no chlamydospore-like structures, or very few when present. Positive for chlamydospore-like structures among 15 strains other than T. tonsurans was one strain at day 5 and six strains at day 8. As for the identification of T. tonsurans, presence of chlamydospore-like structures showed 92.0% sensitivity (23/25) and 93.3% specificity (14/15) at day 5, and 100% sensitivity (25/25) and 60.0% specificity (9/15) at day 8. Electron microscopic findings suggest chlamydospore-like structures are not true chlamydospores but are produced by inflation of actively growing hyphae by developing vacuoles in cells. In conclusion, observation of development of chlamydospore-like structures in culture media is the simplest method for identification of T. tonsurans. [ABSTRACT FROM AUTHOR]

• UvATG7 , the ortholog of autophagy related gene ATG7 in baker's yeast, was identified in rice false smut fungus U. virens. • The subcellular location of some UvAtg7 protein is overlapped with ortholog of Atg8 in U. virens. • Disruption of UvAtg7 totally blocks the autophagic degradation in U. virens. • UvAtg7 is important for full virulence and capacity of conidium and chlamydospore production in U. virens. Autophagy is a conserved mechanism for nutrient and cytoplasmic components recycling in eukaryotic cell, in which E1-like enzyme Atg7 activates ubiquitin-like conjugation in the autophagy pathway. In plant pathogenic fungi Ustilaginoidea virens , UvAtg7, an ortholog of AAtg7 in baker's yeast was identified and functionally investigated. UvAtg7 was confirmed to be essential for autophagy, because the disruption of UvATG7 gene in U. virens completely blocked the fusion of autophagosome-like into vacuoles and catalytic degradation of GFP-UvAtg8 under N-starving condition. The fluorescent signal indicated UvAtg7 protein was dispersed in cytoplasma, but spatially coordinated with core autophagy protein UvAtg8 on occasion. Interestingly, disruption of UvATG7 in U. virens caused slightly reduction in mycelial growth, but resulted in a considerable decrease in virulence, conidia production in YT broth and chlamydospore formation on rice false smut balls. Moreover, the UvATG7 deletion mutants exhibited increased sensitivity to cell wall integrity stress caused by congo red and calcofluor white, meanwhile the UvATG7 deletion mutants showed decreased sensitivity to osmotic stress, cell membrane stress and reactive oxygen stress caused by sorbitol, sodium dodecyl sulfate and H 2 O 2 , respectively. All of these defects in UvATG7 deletion mutants could be partially or completely restored by gene complementation. In general, our study indicates that UvAtg7 is essential in autophagy pathway and contributes to mycelial growth, virulence, asexual reproduction and cell stress response in U. virens. [ABSTRACT FROM AUTHOR]

Hyphae are usually the only fungal elements found in tissue of mucormycosis, and other fungal elements are quite rarely encountered. We found chlamydospores in bronchial lumina in autopsied tissue of pulmonary mucormycosis of a diabetic patient. Chlamydospores are thick -walled, asexually produced spores arising from the modification of a hyphal segment. This is the first histologic demonstration of chlamydospores in mucormycosis in which the causative fungus is culturally identified to species level. Rhizopus microsporus var. rhizopodiformis was isolated from the present autopsied pulmonary tissue. A literature review of human infection by this fungus found 27 cases with histopathologic evidence. [ABSTRACT FROM AUTHOR]

Plant pathogens, especially Phytophthora and bacterial species, in re-circulated irrigation water present a significant health risk to nursery and greenhouse crops. Heat treatment at 95°C for 30 s is one of the most reliable technologies for irrigation water decontamination. The primary objective here was to examine whether the water temperature required to inactivate major pathogens in re-circulated irrigation water can be lowered from 95°C to conserve energy and improve horticultural profitability while reducing environmental footprint. Specifically, we investigated the effect of water temperature on Phytophthora nicotianae zoospore survival in the laboratory and on annual vinca under greenhouse conditions. We also assessed the effect of water temperature on survival of chlamydospores of P. nicotianae, oospores of P. pini, six plant pathogenic bacterial species and Escherichia coli. The zoospores of P. nicotianae did not survive and cause any disease on annual vinca when exposed to 42°C for 12 h or 48°C for 6 h. No chlamydospores of P. nicotianae survived 42°C for 24 h or 48°C for 6 h, nor did the oospores of P. pini at 42°C for 12 h or 48°C for 6 h. In addition, none of the seven bacterial species survived 48°C for 24 h. These results indicate that the required water temperature to eliminate Phytophthora and bacterial species may be lowered substantially from 95°C by longer exposure time, improving the economics and environmental footprint, without sacrificing efficacy of heat treatment. [ABSTRACT FROM AUTHOR]

Abstract: In the present paper, a novel method to accelerate sludge granulation is presented. Inoculation with chlamydospores of Phanerochaete sp. HSD accelerated sludge granulation during the treatment process of phenol wastewater, and the sludge granulation rate reached 66±2% on day 7, 32 days earlier than that of the control inoculated with activated sludge only. Aerobic granule in R1 (AGR1) showed an annual ring-like multilayer structure and a primary core also existed in the nuclear area of the granule. The mechanism of rapid granulation revealed that the chlamydospore could survive in phenol wastewater and form the primary matrix on which aerobic granule was developed layer by layer. In addition, AGR1 developed in a phenol uptake system to counteract the adverse effects of phenol inhibition. Higher tolerance toward wastewater with high phenol strength was exhibited, and the maximum specific phenol degradation rate reached 1.54gphenolg−1 VSSday−1. [Copyright &y& Elsevier]

Copyright of Journal of Medical Mycology / Journal de Mycologie Médicale is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Candida africana differs from the common strains of C. albicans and C. dubliniensis morphologically, physiologically, genetically, and, in particular, clinically. This fungal pathogen is primarily recovered from genital specimens, especially in vaginal specimens. In this investigation, we reexamined 195 vaginal C. albicans isolates for the presence of C. africana and C. dubliniensis by using hyphal wall protein 1 ( HWP1) gene polymorphisms. All study isolates were confirmed to be C. albicans, and none were verified as either C. africana or C. dubliniensis. In conclusion, the HWP1 gene polymorphisms offer a useful tool in the discrimination of C. africana, C. albicans, and C. dubliniensis. Further studies may highlight the pathogenesis and importance of this yeast in vulvovaginal candidiasis. [ABSTRACT FROM AUTHOR]