Growth, morphology, and formation of cinnabarin in Pycnoporus cinnabarinus in relation to different irradiation spectra.

BACKGROUND: The demand for natural pigments in general, and for fungi-derived pigments in particular, is constantly rising. Wood-decomposing fungi represent a promising source for natural pigments and they are usually easy to cultivate in pure culture. One of them, i.e., Pycnoporus cinnabarinus, offers a highly interesting spectrum of bioactivity, partly due to the formation of the orange-red pigment cinnabarin. However, apart from a few studies addressing its diverse potential biotechnological applications, there is still a large gap of knowledge concerning the influence of light on the formation of cinnabarin. The aim of this work was to investigate the effect of different irradiations on the cinnabarin content, the growth, and the morphology of three different P. cinnabarinus strains. We used highly standardized irradiation conditions and cultivation techniques in combination with newly developed methods for the extraction and direct quantification of cinnabarin. RESULTS: Red, green, blue, and UV-A irradiation (mean irradiance Ee = 1.5 ± 0.18 W m-2) had considerable effects on the growth and colony appearance of all three P. cinnabarinus strains tested. The cinnabarin content determined was, thus, dependent on the irradiation wavelength applied, allowing strain-specific thresholds to be defined. Irradiation with wavelengths below this strain-specific threshold corresponded to a lower cinnabarin content, at least at the intensity applied. The orange-red pigment appeared by light microscopy as incrusted extracellular plaques present on the hyphal walls. Highly efficient vegetative propagation occurred by arthroconidia, and we observed the tendency that this asexual reproduction was (i) most frequent in the dark but (ii) never occurred under UV-A exposure. CONCLUSION:  This study highlights a differential photo-dependence of growth, morphology, and cinnabarin formation in P. cinnabarinus. This confirms that it is advisable to consider the wavelength of the light used in future biotechnological productions of natural pigments.

Risk of Exposure to Coccidioides spp. in the Temblor Special Recreation Management Area (SRMA), Kern County, CA.

The Temblor Mountain Special Recreation Area (SRMA) on the western flank of the San Joaquin Valley, CA, is located in the endemic area of Coccidioides, a fungal pathogen responsible for the increasing incidence of coccidioidomycosis (Valley fever). Recreationists in the SRMA, such as off-highway vehicle (OHV) drivers and mountain bikers who disturb the soils, are at risk of being exposed to airborne arthroconidia (asexual spores) of the pathogen. To reduce the risk of pathogen exposure for visitors, the Bureau of Land Management (BLM) plans to limit recreational activities to areas with a reduced pathogen presence. They envision an official OHV park in the future, by also restricting access to areas with ongoing restoration efforts and by limiting soil erosion in sensitive areas. To investigate which soils in the Temblor SRMA are most likely to support the growth of Coccidioides spp., soil samples were collected over a 3-year period from dominant soil types in a northern and a southern sampling area and analyzed for the pathogen using a culture-independent PCR-based method. In addition, soil pH and electrical conductivity were determined. The results of this study revealed slight genetic variance in the Coccidioides sequences obtained from the soils of the Temblor SRMA. An analysis of variance (ANOVA) could not confirm differences in soil pH and electrical conductivity (EC) between the different soil types investigated and between sites where the pathogen was detected compared to sites where it could not be found. However, the year of sampling appeared to have an influence on observed soil pH and EC, and the presence of the pathogen. Of all dominant soil types investigated, those belonging to the Littlesignal-Cochora association were the least likely to contain the pathogen, whereas soils of the Beam-Panoza-Hillbrick association appeared more supportive. In addition to pointing out OHV areas with lower pathogen exposure risk in the Temblor SRMA, recommendations were made to educate visitors and BLM workers about the risk of contracting Valley fever.

Valley Fever: Pathogenesis and Evolving Treatment Options.

Coccidioidomycosis, also termed Valley fever, is a fungal infection caused by the inhalation of Coccidioides endospores. Once inhaled by a human host, the arthroconidia endospores travel to the lungs' alveoli to transform into spherules that grow and rupture to release more endospores. In the host immune response, macrophages, neutrophils, and dendritic cells will recognize the fungal antigen, producing pro-inflammatory cytokine. Th2 lymphocytes (type 2 helper T cells) are theorized to be the main human defense against Coccidioides given that Th2 deficiency is seen in patients with disseminated forms of the disease. A common triad of symptoms of coccidioidomycosis, also called "desert rheumatism," include fever, erythema nodosum, and arthralgia, often accompanied by a respiratory problem. In a clinical setting, along with the evaluation of symptoms, a medical provider may also test the patient's blood using antibody tests or perform microscopy to directly detect the presence of Coccidioides in a patient tissue sample for confirmation of a diagnosis. Imaging modalities may also be used to determine lung involvement and assess disease progression. A majority of coccidioidomycosis cases do not require specific treatment and will resolve on their own, so an approach with symptomatic treatment in mind is appropriate. If symptoms do not resolve, azoles or amphotericin B may be used, with the standard drug of choice being fluconazole (Diflucan, Pfizer, New York, New York, United States). Treatment varies depending on the immunocompetency of the patient. To name a few, pregnant patients and those with history of human immunodeficiency virus (HIV) or transplantation require special considerations.

Efficacy of common disinfection processes against infective spores (arthroconidia) and mycelia of Microsporum gallinae causing avian dermatophytosis.

Background and Aim: Microsporum gallinae is the major dermatophyte species that causes avian dermatophytosis. Disinfection plays an important role in controlling and preventing dermatophytosis; however, information about the effect of common disinfection processes on M. gallinae is limited. This study aimed to investigate the disinfection efficacy of ultraviolet (UV) irradiation, heat treatment, detergents, and germicides against infective spores (arthroconidia) and vegetative mycelia of M. gallinae. Materials and Methods: The minimum inhibitory and minimum fungicidal concentrations of benzalkonium chloride, chlorhexidine, ethanol, formaldehyde, glutaraldehyde, hydrogen peroxide, phenol, povidone-iodine, and sodium hypochlorite germicides against arthroconidia and mycelia of M. gallinae American type culture collection (ATCC) 90749 were determined by broth microdilution. Time-kill assays were used to determine the fungicidal efficacy of moist heat treatment, UV irradiation, commercially available detergents, and germicides. Results: There were no significant differences between the arthroconidia and mycelia growth stages of M. gallinae ATCC 90749 in the magnitude of the log10 cell reductions in the number of viable fungal cells induced by the disinfection treatments (all p > 0.05). Moist heat treatment at 40°C did not reduce the number of viable fungal cells at any time (1-60 min); however, treatment at 50°C for 25 min and either 60°C or 80°C for 5 min eliminated > 99.999% of viable fungal cells. Irradiation of fungal cultures with UVC and UVB at doses higher than or equal to 0.4 and 0.8 J/cm2, respectively, resulted in a 5-log10 reduction in the number of viable fungal cells, whereas UVA only reduced the number of viable fungal cells by < 2-log10 up to a dose of 1.6 J/cm2. All the tested detergents demonstrated minimal fungicidal effects with < 1-log10 reductions in the number of viable fungal cells at concentrations up to 8% w/v. All of the tested germicides eradicated the fungus after treatment for 1 min at 1-1000× minimum inhibitory concentration (MIC), except for hydrogen peroxide, which was not fungicidal after treatment for 20 min at 100× MIC. Conclusion: Moist heat treatment at temperatures greater than or equal to 50°C, UVC and UVB irradiation at doses higher than or equal to 0.4 and 0.8 J/cm2, respectively, and treatment with all tested germicides except hydrogen peroxide can be considered effective processes for disinfecting the fungus M. gallinae from the equipment employed in poultry farming. In contrast, commercially available detergents are not suitable for use as M. gallinae disinfectants.

Description of a new species of Gerhardtia (Lyophyllaceae, Agaricales) from Japan based on morphological and molecular phylogenetic analyses and live culture characteristics.

We describe a new species of Gerhardtia from Japan based on basidiomata morphology, live culture characteristics, and molecular phylogenetic analyses. Gerhardtia venosolamellata is found on broad-leaf litter, and is characterized by tricholomatoid to marasmioid basidiomata, an off-white to pale salmon-pink pileus surface with faint marginal striae, subdistant lamellae with lateral veins, a tomentose to strigose stipe base with hyphal strands generating arthroconidia measuring 4-7 × 2-3 µm, cyanophilic, elongate-ellipsoid to cylindrical, slightly verrucose or undulate basidiospores measuring 4.5-6 × 2.5-3 µm, and cyanophilic basidia measuring 25-35 × 5-6 µm and containing siderophilous granules. Phylogenetic analyses based on the internal transcribed spacer and large subunit regions of the fungal nrDNA indicates that G. venosolamellata is related to G. sinensis and G. highlandensis, but differs from the former with respect to basidiomata color, basidiospore shape, and habitat. An isotype specimen of G. highlandensis exhibited relatively close lamellae without veins, and slightly larger basidiospores (4.5-6.5 × 2.5-3 µm). Cultured mycelia of G. venosolamellata produced arthroconidia measuring 4.5-8.5 × 2.5-3 µm with both schizolytic and rhexolytic secession on MA and PDA media, and chlamydospores occasionally covered with crystals on MA and MYG media.

Towards a Standardized Procedure for the Production of Infective Spores to Study the Pathogenesis of Dermatophytosis.

Dermatophytoses are superficial infections of human and animal keratinized tissues caused by filamentous fungi named dermatophytes. Because of a high and increasing incidence, as well as the emergence of antifungal resistance, a better understanding of mechanisms involved in adhesion and invasion by dermatophytes is required for the further development of new therapeutic strategies. In the last years, several in vitro and in vivo models have emerged to study dermatophytosis pathogenesis. However, the procedures used for the growth of fungi are quite different, leading to a highly variable composition of inoculum for these models (microconidia, arthroconidia, hyphae), thus rendering difficult the global interpretation of observations. We hereby optimized growth conditions, including medium, temperature, atmosphere, and duration of culture, to improve the sporulation and viability and to favour the production of arthroconidia of several dermatophyte species, including Trichophyton rubrum and Trichophyton benhamiae. The resulting suspensions were then used as inoculum to infect reconstructed human epidermis in order to validate their ability to adhere to and to invade host tissues. By this way, this paper provides recommendations for dermatophytes culture and paves the way towards a standardized procedure for the production of infective spores usable in in vitro and in vivo experimental models.

Dimorphism in Neopseudocercosporella capsellae, an Emerging Pathogen Causing White Leaf Spot Disease of Brassicas.

White leaf spot pathogen: Neopseudocercosporella capsellae causes significant damage to many economically important Brassicaceae crops, including oilseed rape through foliar, stem, and pod lesions under cool and wet conditions. A lack of information on critical aspects of the pathogen's life cycle limits the development of effective control measures. The presence of single-celled spores along with multi-celled conidia on cotyledons inoculated with multi-celled conidia suggested that the multi-celled conidia were able to form single-celled spores on the host surface. This study was designed to demonstrate N. capsellae morphological plasticity, which allows the shift between a yeast-like single-celled phase and the multi-celled hyphal phase. Separate experiments were designed to illustrate the pathogen's morphological transformation to single-celled yeast phase from multi-celled hyphae or multi-celled macroconidia in-vitro and in-planta. Results confirmed the ability of N. capsellae to switch between two morphologies (septate hyphae and single-celled yeast phase) on a range of artificial culture media (in-vitro) or in-planta on the host surface before infection occurs. The hyphae-to-yeast transformation occurred through the production of two morphologically distinguishable blastospore (blastoconidia) types (meso-blastospores and micro-blastospores), and arthrospores (arthroconidia).

Role of arthroconidia in biofilm formation by Trichosporon asahii.

BACKGROUND: Trichosporon asahii is the major causative agent of disseminated and deep-seated trichosporonosis. It is capable of forming biofilms on surfaces, leading to medical device-related infection.Trichosporon asahii may be present as yeast form, hyphae and/or arthroconidia; however, the relationship between its biofilm-forming ability and its morphological transition is unclear. OBJECTIVES: We investigated whether the T. asahii morphological transition contributes to its biofilm formation. We also determined the conditions required to induce each of the morphologies. METHODS: Three high- and three low-biofilm-producing strains (HBS and LBS, respectively) were selected using a biofilm formation assay, and the cell surface hydrophobicity of these six strains was measured. For each strain, the morphology was observed and the number of each morphological form (yeast form, hypha and arthroconidium) was counted to calculate the ratio. Finally, the ability of cells each morphological type to adhere to the polystyrene substrate was evaluated. RESULTS: The HBS exhibited abundant arthroconidia and hyphae; in contrast, the LBS produced mainly hyphae with few or no arthroconidia. The production of hyphae was increased by nitrogen-containing medium, and the production of arthroconidia was increased by nitrogen-deficient medium. Cells incubated under nitrogen-deficient conditions showed higher adherence to a polystyrene surface than those incubated in the presence of nitrogen. CONCLUSION: Arthroconidia of T. asahii play a key role in biofilm formation by promoting cellular adhesion.

Systemic coccidioidomycosis in a dog in Northeastern Brazil / Coccidioidomicose sistêmica em um cão no Nordeste do Brasil

ABSTRACT: We described a case of systemic infection by Coccidioides sp. in a dog. An adult, mixed breed, free-ranging male dog presented with clinical signs that included apathy, cachexia, anorexia, limited mobility with sternal recumbency, bilateral mucopurulent ocular discharge, dyspnoea, pulmonary crepitation, erosive and nodular lesions on the skin, and swelling and stiffness of the left tibiotarsal joint. The dog was submitted to a postmortem examination. Grossly, there were multiple yellow to white nodules in various organs. Histologically, the lesions were characterized as pyogranulomatous inflammation associated with fungal spherules morphologically consistent with Coccidioides sp. The dog was concomitantly diagnosed with undifferentiated sarcoma affecting the skin, lymph nodes, liver, and testicles. The diagnosis of coccidioidomycosis was made based on the histologic changes associated with morphotintorial features and positive immunolabeling of organisms with anti-Coccidioides immunohistochemistry. This case demonstrated that Coccidioides sp. can infect dogs that inhabit urban centers in the semiarid region of Northeastern Brazil, likely due to exposure to dust from contaminated environments.

RESUMO: Descreve-se um caso de infecção sistêmica por Coccidioides em um cão. Um cão adulto, sem raça definida e errante, atendido com sinais clínicos que incluíram apatia, caquexia, anorexia, dificuldade de locomoção com decúbito esternal, secreção ocular bilateral mucopurulenta, dispneia, crepitação pulmonar, lesões erosivas e nodulares na pele, aumento de volume e rigidez na articulação tibiotársica do membro pélvico esquerdo. O cão foi submetido a um exame post-mortem. Macroscopicamente, haviam múltiplos nódulos amarelo-brancacentos em vários órgãos. Histologicamente, as lesões foram caracterizadas por inflamação piogranulomatosa associada a esférulas fúngicas morfologicamente consistentes com Coccidioides sp. O cão foi diagnosticado concomitantemente com sarcoma indiferenciado afetando a pele, linfonodos, fígado e testículos. O diagnóstico de coccidioidomicose foi realizado com base nas alterações histológicas associadas as características morfotintoriais e imunomarcação positiva dos organismos com anti-Coccidioides na imuno-histoquímica. Esse caso demonstra que Coccidioides sp. pode infectar cães que habitam centros urbanos no semiárido do Nordeste do Brasil, provavelmente devido à exposição a poeira de ambientes contaminados.

Proper Care and Feeding of Coccidioides: A Laboratorian's Guide to Cultivating the Dimorphic Stages of C. immitis and C. posadasii.

Coccidioidomycosis ("Valley fever") is caused by Coccidioides immitis and C. posadasii. These fungi are thermally dimorphic, cycling between mycelia and arthroconidia in the environment and converting into spherules and endospores within a host. Coccidioides can cause a broad spectrum of disease that can be difficult to treat. There has been a steady increase in disease, with an estimated 350,000 new infections per year in the United States. With the increase in disease and difficulty in treatment, there is an unmet need to increase research in basic biology and identify new treatments, diagnostics, and vaccine candidates. Here, we describe protocols required in any Coccidioides laboratory, such as growing, harvesting, and storing the different stages of this dimorphic fungal pathogen. © 2020 Wiley Periodicals LLC. Basic Protocol 1: Growth and harvest of liquid mycelia cultures for extractions Alternate Protocol 1: Large-volume growth and harvest of liquid mycelia cultures Basic Protocol 2: Mycelial growth on solid medium Alternate Protocol 2: Maintaining mycelial growth on solid medium Basic Protocol 3: Harvesting and quantification of arthroconidia Alternate Protocol 3: Long-term storage of arthroconidia Basic Protocol 4: Parasitic spherule growth and harvest Alternate Protocol 4: Obtaining endospores from spherules Basic Protocol 5: Intranasal infection of murine models.

The best type of inoculum for testing the antifungal drug susceptibility of Microsporum canis: In vivo and in vitro results.

BACKGROUND: Data correlating in vitro drug susceptibility of Microsporum canis with clinical outcomes of its infections are lacking as well as the most suitable inoculum and incubation time in broth microdilution assays. OBJECTIVES AND METHODS: Microsporum canis strains were collected from animal hosts that tested positive (Group I; n = 13) and negative (Group II; n = 14) to this pathogen following itraconazole (ITC) therapy. In vitro ITC susceptibility was assessed according to the Clinical Laboratory Standards Institute (CLSI M38-A2) methodology using conidia, hypha-conidia and arthroconidia at 3 and 7 days of incubation in order to assess the most suitable inoculum and incubation time. Successively, ketoconazole (KTC), voriconazole (VRC), terbinafine (TRB), posaconazole (PSZ), fluconazole (FLC) and griseofulvin (GRI) susceptibilities were assessed using the chosen inoculum. RESULTS: The MIC values of ITC after three-day incubation were equal than those recorded after 7-day incubation. Itraconazole MICs were ≤1 µg/mL for strains from Group II and >1 µg/mL for those of Group II only when conidia were used. All strains showed high susceptibility to VRC, POS, TEB and low susceptibility to ITC, KTC, GRI and FLC regardless of the source and incubation time. CONCLUSIONS AND CLINICAL IMPORTANCE: Results suggest that correlation between the in vitro results and clinical outcome was observed only by incubating conidia for 3 days at 30 ± 2°C. These conditions might be most suitable to assess in vitro susceptibility of M. canis and assist in determining the occurrence of drug resistance and cross-resistance phenomena.

Agrobacterium-mediated transformation of arthroconidia obtained from the edible mushroom Hypsizygus marmoreus.

Using the carboxin resistance gene from Pleurotus eryngii as a selective marker, we introduced foreign DNA into the arthroconidia of Hypsizygus marmoreus through Agrobacterium-mediated transformation. The function of the exogenous GUS (ß-glucuronidase) gene driven by the CaMV35S promoter was detected in the transformants.

The detection of Coccidioides from ambient air in Phoenix, Arizona: Evidence of uneven distribution and seasonality.

Coccidioidomycosis is a debilitating fungal disease caused by inhalation of arthroconidia. We developed a novel approach for detection of airborne Coccidioides and used it to investigate the distribution of arthroconidia across the Phoenix, Arizona, metropolitan area. Air filters were collected daily from 21 stationary air-sampling units across the area: the first set collected before, during and after a large dust storm on August 25, 2015, and the second over the 45-day period September 25-November 8, 2016. Analysis of DNA extracted from the filters demonstrated that the day of the dust storm was not associated with increase of Coccidioides in air samples, although evidence of the low-level polymerase chain reaction (PCR) inhibition was observed in DNA extracted from samples collected on the day of the dust storm. Testing over 45 days identified uneven geographic distribution suggesting Coccidioides hot spots. In 2016, highest daily concentration of arthroconidia was observed between September 25-October 20, and only sporadic low levels were detected after that. These results provide evidence of seasonality and uneven spatial distribution of Coccidioides in the air. Our results demonstrate that routine air monitoring for arthroconidia is possible and provides an important tool for Coccidioides surveillance, which can address important questions about environmental exposure and human infection.

High pullulan biosynthesis from high concentration of glucose by a hyperosmotic resistant, yeast-like fungal strain isolated from a natural comb-honey.

A novel, yeast-like fungal strain, Aureobasidium melanogenum TN3-1, that was isolated from natural honey can actively transform 140.0 g/L of glucose into 110.29 ±â€¯2.17 g/L of pullulan during fermentation, whereas A. melanogenum P16 and TN1-2 converted 140.0 g/L of glucose into only 45.81 ±â€¯1.7 g/L and 48.7 ±â€¯2.6 g/L of pullulan, respectively. It was noted that most of the cells in the culture of the strain TN3-1 were arthroconidia, while all of the yeast-like fungal cells of A. melanogenum P16 cultivated under the same conditions were blastoconidia. The cell sizes, cell walls and the number of small vacuoles of A. melanogenum TN3-1 were also much larger, thicker and higher, respectively, than those of A. melanogenum P16. The glycerol, trehalose and glycogen content in the A. melanogenum TN3-1 cells was higher than that of the A. melanogenum P16 and TN1-2 cells.

Arthroconidia in lung tissue: an unusual histopathological finding in pulmonary coccidioidomycosis.

Coccidioides immitis/posadasii presents in mycelial form with branching hyphae and arthroconidia when cultured in the laboratory. On histopathology, the presence of endospore-containing spherules is considered diagnostic of coccidioidomycosis. Here we report an unusual case of coccidioidomycosis with hyphae and arthroconidia in pulmonary tissue sections. A 49-year-old male patient with intermittently treated pulmonary coccidioidomycosis sought treatment for residual pulmonary complaints. A cavity in the left upper lobe was seen on computed tomographic scan. Due to minimal improvement of symptoms despite treatment with fluconazole, a left upper lobectomy was ultimately performed. Coccidioides mimmitis/posadasii was identified by culture and DNA probe from the lobectomy specimen. The histopathology showed a fibro-cavitary lesion, with arthroconidia and hyphal structures, but no typical endospore-forming spherules. While uncommon, C. immitis/posadasii may present with hyphae and arthroconidia on histopathology. Pathologists should be aware of this unusual presentation; culture remains the most reliable method for definitive diagnosis.

Vanillin Promotes the Germination of Antrodia camphorata Arthroconidia through PKA and MAPK Signaling Pathways.

Wild fruiting bodies of medicinal mushroom Antrodia camphorata are only found on the endemic species bull camphor tree, Cinnamomum kanehirae, in Taiwan. Despite the evident importance of the host components in promoting the growth of A. camphorata, insights into the underlying mechanisms are still lacking. Here, we first evaluated effects of the compounds from C. kanehirai, C. camphora, and A. camphorata, and their structural analogs on the germination rate of A. camphorata arthroconidia. Among the 54 tested compounds, vanillin (4-hydroxy-3-methoxybenzaldehyde) was determined as the optimum germination promoter, while o-vanillin and 1-octen-3-ol as major negative regulators of arthroconidia germination. Second, the protein patterns of arthroconidia after 24 h of incubation in the presence or absence of vanillin were compared via isobaric tags for relative and absolute quantitation (iTRAQ)-based proteomics. Via bioinformatic analysis, it was found that 61 proteins might relate to the germination of arthroconidia, in which 16 proteins might involve in two potential protein kinase A (PKA) and mitogen-activated protein kinase (MAPK) signaling pathways in the vanillin-promoted germination of A. camphorata arthroconidia. Last, the mRNA expression levels of the 16 germination-related genes in the potential PKA and MAPK signaling pathways were analyzed by quantitative real time PCR. Together, our results are beneficial for the elucidation of molecular mechanisms underlying the germination of A. camphorata arthroconidia.

The Neurospora crassa PP2A Regulatory Subunits RGB1 and B56 Are Required for Proper Growth and Development and Interact with the NDR Kinase COT1.

COT1 is the founding member of the highly conserved nuclear Dbf2-related (NDR) Ser/Thr kinase family and plays a role in the regulation of polar growth and development in Neurospora crassa and other fungi. Changes in COT1 phosphorylation state have been shown to affect hyphal elongation, branching, and conidiation. The function of NDR protein kinases has been shown to be regulated by type 2A protein phosphatases (PP2As). PP2As are heterotrimers comprised of a catalytic and scaffolding protein along with an interchangeable regulatory subunit involved in determining substrate specificity. Inactivation of the N. crassa PP2A regulatory subunits rgb-1 and b56 conferred severe hyphal growth defects. Partial suppression of defects observed in the rgb-1RIP strain (but not in the Δb56 mutant) was observed in cot-1 phosphomimetic mutants, demonstrating that altering COT1 phosphorylation state can bypass, at least in part, the requirement of a functional RGB1 subunit. The functional fusion proteins RGB1::GFP and B56::GFP predominantly localized to hyphal tips and septa, respectively, indicating that their primary activity is in different cellular locations. COT1 protein forms exhibited a hyperphosphorylated gel migration pattern in an rgb-1RIP mutant background, similar to that observed when the fungus was cultured in the presence of the PP2A inhibitor cantharidin. COT1 was hypophosphorylated in a Δb56 mutant background, suggesting that this regulatory subunit may be involved in determining COT1 phosphorylation state, yet in an indirect manner. Reciprocal co-immunoprecipitation analyses, using tagged COT1, PPH1, RGB1, and B56 subunits established that these proteins physically interact. Taken together, our data determine the presence of a functional and physical link between PP2A and COT1 and show that two of the PP2A regulatory subunits interact with the kinase and determine COT1 phosphorylation state.

Nannizziopsis guarroi infection in 2 Inland Bearded Dragons (Pogona vitticeps): clinical, cytologic, histologic, and ultrastructural aspects.

Chrysosporium-related infections have been increasingly reported in reptiles over the last 2 decades. In this report, we describe clinical, cytologic, histopathologic, and ultrastructural aspects of Chrysosporium-related infection in 2 Inland Bearded Dragons (Pogona vitticeps). Case 1 was presented for an enlarging raised lesion over the left eye and multiple additional masses over the dorsum. Case 2 was submitted to necropsy by the referring veterinarian for suspected yellow fungus disease. Impression smears of the nodules in case 1 revealed granulomatous to pyogranulomatous inflammation and many septate, variably long, 4-10 µm wide, often undulated hyphae, and very rare conidia. Postmortem impression smears of the superficial lesions of case 2 contained large numbers of solitary conidia and arthroconidia and low numbers of hyphae with similar morphology to case 1. Histopathology of the 2 cases revealed severe, multifocal, chronic, ulcerative, nodular pyogranulomatous dermatitis, with myriad intralesional septate hyphae, and arthroconidia. Fungal culture and molecular sequencing in both cases indicated infection with Nannizziopsis guarroi.