Molecular identification, phylogenetic analysis and antifungal susceptibility patterns of Aspergillusnidulans complex and Aspergillusterreus complex isolated from clinical specimens.

OBJECTIVE: Aspergillus sections Terrei and Nidulantes are the less common causes of invasive aspergillosis and pulmonary aspergillosis (PA) in immunocompromised patients when compared to A. fumigatus and A. flavus. Identifying these fungi as the infectious agent is crucial because of the resistance to amphotericin B (AMB) and increased lethality. The aim of this study was to identify the molecular status, evaluate the genetic diversity and examine the antifungal susceptibility profile of the uncommon Aspergillus species. Forty-five uncommon Aspergillus species were identified based on the microscopic and macroscopic criteria. Then, the molecular identification was performed using the sequencing beta tubulin (benA) gene. In vitro antifungal susceptibility to amphotericin B (AMB), itraconazole (ITC), ravuconazole (RAV), voriconazole (VRC), caspofungin (CFG) isavuconazole (ISA) and posaconazole (POS) test was performed according to the CLSI M38-A2 guidelines. RESULTS: A. terreus was the most species detected, followed by A. nidulans, A. latus, A.ochraceus, and A. citrinoterreus, respectively. The analysis of the benA gene showed the presence of 12 distinct genotypes among the A. terreus isolates. The other species did not show any intraspecies variation. CFG exhibited the lowest MEC50/MIC50 (0.007µg/mL), followed by POS (0.125µg/mL), VRC, ITC, ISA (0.25µg/mL), RAV (0.5µg/mL), and AMB (8µg/mL). Among all the isolates, only 15.5% (7/45) were susceptible to AMB. CONCLUSION: Antifungal susceptibility pattern of the uncommon Aspergillus species is useful to improve patient management and increase knowledge concerning the local epidemiology. Moreover, this information is necessary when an outbreak dealing with drug-resistant infections occurs.

Simultaneous detection of Aspergillus nidulans, Aspergillus luchuensis and Lichtheimia sp. in a bovine abortion.

Abortion in dairy cattle may be caused by infectious (viruses, fungi and protozoa) and non-infectious causes mostly related to bad management practices and genetic factors. Recently, the significant contribution of mycotic infection to bovine abortion has been recognized. This report describes an abortion case in a Chianina cow due to Aspergillus nidulans, Aspergillus luchuensis and Lichtheimia sp. diagnosed by histology, cytology, culture and molecular assays. A mixed infection due to more than one fungus in abortion is rarely demonstrated. To our knowledge, this is the first case of bovine abortion caused by co-infection with three different moulds.

Genetic diversity and antifungal susceptibility patterns of Aspergillus nidulans complex obtained from clinical and environmental sources.

The molecular epidemiology and antifungal susceptibility of Aspergillus nidulans species complex has not been well studied. To evaluate the genetic diversity and antifungal susceptibility patterns of clinical and environmental isolates of A. nidulans complex. Sixty clinical and environmental isolates of Aspergillus section Nidulantes were collected from five countries (Iran, The Netherlands, Spain, Portugal and Greece). The species were molecularly identified by sequencing of ß-tubulin gene. The genetic diversity of A nidulans complex isolates (n = 54) was determined with a microsatellite genotyping assay. Antifungal susceptibility profile was determined using EUCAST method. The isolates were classified as A nidulans (46.7%), A spinulosporus (26.6%), A quadrilineatus (10%), A pachycristatus (3.3%), A rugulosus (3.3%), A unguis (5%), A creber, (1.7%), A olivicola (1.7%) and A sydowii (1.7%). Thirty-four sequence types (STs) were identified among the 54 A nidulans complex isolates. A high level of genetic diversity was found among A nidulans sensu stricto strains but low diversity was found among A spinulosporus strains. Amphotericin B showed high MICs to all species. The most active azole was posaconazole (GM = 0.64 mg/L), while itraconazole showed the highest MICs among azoles (GM = 2.95 mg/L). A spinulosporus showed higher MICs than A nidulans sensu stricto for all antifungals except for micafungin and anidulafungin. Interspecies variations may result in differences in antifungal susceptibility patterns and challenge antifungal therapy in infections caused by A nidulans. Differences in the distribution of STs or persistence of multiple STs might be related to the sources of isolation and niche specialisation.

Sequence analysis of isolates of Aspergillus from patients with chronic and allergic aspergillosis reveals a spectrum of cryptic species.

AIM: To establish the prevalence and antifungal susceptibilities of Aspergillus cryptic species from respiratory samples. Methods: Retrospective susceptibility data on Aspergillus species cultured between 2015 and 2017 by 'high volume culture' (HVC) versus 'conventional' culture techniques. RESULTS: Fifty-six (2.5%) isolates were identified as Aspergillus cryptic species by sequencing of ITS, BenA and CalM gene loci. Recovery was higher in HVCs compared to conventional cultures. Common cryptic species were Aspergillus montevidensis (n = 15), A. creber (n = 11), A. sydowii (n = 5) and A. calidoustus (n = 4). Eighteen (32.1%) isolates had minimum inhibitory concentration (MIC) values ≥4 mg/l to amphotericin B, and 19.1-60.1% had MIC values ≥8 mg/l to the triazoles. CONCLUSION: HVC increases the likelihood of recovery of cryptic species. MIC values to antifungals were high.

Fungal osteomyelitis in a patient with chronic granulomatous disease: Case report and review of the literature.

Chronic granulomatous disease (CGD) is the most common of the primary immunodeficiency in children. It is caused by single gene defect resulting in dysfunctional nicotinamide adenine dineucleotide phosphate (NADPH) oxidase complex causing recurrent bacterial and fungal infections. Here we present the case of a 9 year old boy who was a known case of CGD since three years of age. He presented with recent history of fever, left sided pain in the scapular region and difficulty in breathing. Chest imaging revealed developing left upper lobe consolidation and erosion of the 3rd posterior rib. The child underwent video assisted thoracoscopic surgery (VATS) and biopsy of the lesion. Histopathology revealed fungal hyphae which were confirmed to be Aspergillus nidulans on staining. He was successfully treated with voriconazole therapy. We will also review the literature on fungal osteomyelitis in CGD patients.

In Vitro Combination of Isavuconazole with Echinocandins against Azole-Susceptible and -Resistant Aspergillus spp.

In vitro combinations of isavuconazole with echinocandins were evaluated against 30 Aspergillus strains with a two-dimensional checkerboard microdilution method and an agar-based diffusion method. With the checkerboard method, the three combinations showed indifferent interactions for all strains. With the agar-based method, indifferent interactions were found for all strains for isavuconazole-micafungin and isavuconazole-anidulafungin. For the isavuconazole-caspofungin combination, indifference was found in 24/30 strains, synergism in 4/30 strains, and antagonism in 2/30 strains.

The first case of fungal endophthalmitis caused by Emericella nidulans after cataract surgery.

Emericella nidulans is a species that has only rarely been implicated in human disease after cataract surgery. Here, we report the first postoperative case in the literature, as far as we know. The patient was a 50-year-old patient presented with mild anterior uveitis one week after cataract surgery, and hypopion developed over the next two days. First microbiological evaluation and the results of direct microscopy and cultures of the anterior chamber and vitreous samples were found to be negative. Despite vigorous topical and intravitreal (vancomycin and amikacin) therapy, the endophthalmitis did not improve. Anterior chamber paracentesis, vitreous tap and finally complete vitrectomy with removal of the capsular bag including the intraocular lens (IOL) were performed. The anterior chamber, vitreous fluid samples and IOL were submitted to the microbiology laboratory: the culture yielded E. nidulans growth. Ocular inflammation resolved and vision improved on intravenous, subconjunctival and long-term oral voriconazole treatment. E. nidulans can be an important cause of ocular fungal infections including endophthalmitis, and voriconazole seems to be effective for the treatment of E. nidulans endophthalmitis.

Mecanismos y regulación de la hidrólisis enzimática de celulosa en hongos filamentosos: casos clásicos y nuevos modelos / Mechanisms and regulation of enzymatic hydrolysis of cellulose in filamentous fungi: classical cases and new models

La celulosa es la fuente de carbono renovable más abundante de la Tierra. Sin embargo, la estructura de este polímero constituye una barrera física y química para acceder al carbono, lo que ha limitado el aprovechamiento del mismo. En la naturaleza, un pequeño porcentaje de microorganismos pueden degradarla a través de la expresión de celulasas. Dentro de estos microorganismos, uno de los grupos más activos y eficientes son los hongos filamentosos. Esta revisión describe las similitudes y diferencias de los mecanismos de acción de las celulasas y los mecanismos de regulación de su expresión para 3 de los modelos de hongos filamentosos celulolíticos más estudiados: Trichoderma reesei, Aspergillus niger y Aspergillus nidulans, y para un modelo recientemente descrito, Neurospora crassa. Se encontró que los mecanismos de acción enzimática son muy similares en todos los modelos estudiados, no así los mecanismos de regulación génica. Entender las particularidades de cada sistema es fundamental en el desarrollo de estrategias para la mejora de la producción de celulasas, ya sea proporcionando el ambiente óptimo (condiciones de fermentación) o aumentando la expresión en estos microorganismos mediante ingeniería genética (AU)

Cellulose is the most abundant renewable carbon source on earth. However, this polymer structure comprises a physical and chemical barrier for carbon access, which has limited its exploitation. In nature, only a few percentage of microorganisms may degrade this polymer by cellulase expression. Filamentous fungi are one of the most active and efficient groups among these microorganisms. This review describes similarities and differences between cellulase activity mechanisms and regulatory mechanisms controlling gene expression for 3 of the most studied cellulolytic filamentous fungi models: Trichoderma reesei, Aspergillus niger and Aspergillus nidulans, and the recently described model Neurospora crassa. Unlike gene expression mechanisms, it was found that enzymatic activity mechanisms are similar for all the studied models. Understanding the distinctive elements of each system is essential for the development of strategies for the improvement of cellulase production, either by providing the optimum environment (fermentation conditions) or increasing gene expression in these microorganisms by genetic engineering (AU)

Avaliação da mutagenicidade de Piper methysticum L. f. no sistema methG1 em Aspergillus nidulans / Mutagenic evaluation of Piper methysticum L. f. in Aspergillus nidulans methG1 system

O extrato seco da raiz de Piper methysticum L. f. Forster (PIPERACEAE), a kava-kava, é usado no tratamento de diversos problemas envolvendo ansiedade como um dos sintomas. Por não causar dependência, sedação e ter ação ansiolítica, muitas pessoas têm recorrido a kava-kava para auxiliá-las no emagrecimento. Isto pode levar ao consumo indiscriminado da planta e acarretar riscos, pois todo medicamento fitoterápico deve respeitar limites de doses. Um risco na utilização de plantas medicinais é a toxicidade e, dentro deste, a mutagenicidade. Como a mutagenicidade está relacionada com a carcinogenicidade torna-se importante testar este potencial na kava-kava. Assim, o objetivo deste trabalho foi avaliar o potencial mutagênico do extrato seco da raiz de P. methysticum no sistema methG1 em Aspergillus nidulans. A linhagem utilizada foi a biA1methG1, auxotrófica para biotina e metionina. Conídios dormentes de colônias crescidas por cinco dias foram tratados com soluções da kava-kava nas concentrações de 0,35 mg mL-1 e 3,5 mg mL-1, e depois de 24h, semeados em meio seletivo contendo metionina, para análise dos sobreviventes, e sem metionina, para a análise dos mutantes. Os números de sobreviventes e mutantes dos tratamentos foram comparados aos do controle. Os resultados indicaram que o extrato da raiz da kava-kava é mutagênica, pois a freqüência de mutação dos tratamentos foi maior que da mutação espontânea, porém não ocorrendo diferença significativa entre as doses.

The dry root extract of Piper methysticum L. f. Forster (Piperaceae), kava-kava, is used as to treat several health problems involving anxiety symptoms. As it causes no addiction, it can be applied as a sedative and anxiolytic. Many people have been relying on kava-kava as an auxiliary treatment. This can lead to an indiscriminate plant consumption and lead to risks, because all phytotherapic medications must observe dosage limits. One risk in the folk medicinal plant use is toxicity, and within it, mutagenicity. As mutagenicity is closely related to carcinogenicity, it is important to test the kava-kava mutagenicity potential. Thus, the purpose of this work was to test the mutagenicity of the dry root extract of P. methysticum in the methG1 system of Aspergillus nidulans. The bia1methG1 lineage, which is auxotrophic for biotine and methione, was used. Conidia from five-day-old colonies were collected and treated with kava-kava solutions at 0.35 mg mL-1 and 3.5 mg mL-1 concentrations and, after 24h, they were planted in selective growth medium with and without methione, in order to analyze the survivors and mutants, respectively. The number of survivors and mutants analyzed under effect of the treatments was compared with the control. The results indicated that the kava-kava dry root extract is mutagenic, since the mutation frequency of the treatments was higher than spontaneous mutation, however, there were no differences between the doses tested.

Two rare cases of central nervous system opportunistic mycoses.

This article presents two cases of opportunistic mycoses (OMs) of the central nervous system (CNS) caused by Cryptococcus neoformans and Aspergillus nidulans, respectively. The patients were hospitalised in local hospitals between 2009 and 2011 because of unspecific symptoms (fever, headache, and/or weight lost). Duration of symptoms varied from 4 days to over 2 weeks. The patients were treated with antibiotics and symptomatically. OM was not suspected in any of them. The patients became critically ill with symptoms of CNS involvement and were transferred to the Intensive Care Unit (ICU) of the University Hospital for Infectious diseases (UHID) in Zagreb. None of the patients belonged to the high-risk population for developing OMs. They were not HIV-infected, had no transplantation of bone marrow or solid organ, and were not on severe immunosuppressive chemotherapy. Fungi were isolated from cerebrospinal fluid (CSF) samples and, in one patient, from aspirate of cerebral abscess. Isolation and mycological identification of all fungal isolates and in vitro antifungal susceptibility testing of these isolates were done at the Reference Centre for Mycological Diagnostics of Systemic and Disseminated Infections (RCMDSDI) in Zagreb. The patient with cryptococcal meningitis was treated with amphotericin B and fluconazole and the patient with cerebral aspergilloma with voriconazole.

Chronic granulomatous disease of childhood: an unusual cause of recurrent uncommon infections in a 61-year-old man.

Chronic granulomatous disease (CGD) is a rare congenital immunodeficiency that affects 1 : 250,000 of the population, which is characterized by recurrent bacterial and fungal infections and by granuloma formation. We investigated a 61-year-old man presented with a 20-year history of a relapsing skin rash appearing as mildly pruritic and erythematous plaques affecting various body regions. Cutaneous biopsies were taken and sent for histology and tissue culture. Leucocyte function was assessed by determining the generation of reactive oxygen species. Bactericidal activity was assessed in the presence of autologous and homologous sera. Western blotting was performed for protein analysis of the reduced nicotinamide adenine dinucleotide phosphate oxidase system, and mutation screening was carried out using PCR amplification and sequence analysis. Examination of biopsies obtained from lesional skin indicated a suppurative granulomatous process. Tissue cultures grew Aspergillus nidulans and Aspergillus fumigatus (confirmed by PCR). A. nidulans has often been associated with CGD, and the leucocyte function tests supported this diagnosis. Direct DNA sequencing led to the identification of a hemizygous missense novel mutation in CYBB (c.907C>T), which predicts a p.His303Tyr amino-acid substitution in gp91-phox, thus confirming the diagnosis of CGD. In conclusion, we report a case of a rare inherited immunodeficiency, CGD, in a 61-year-old man, and describe the novel hemizygous missense mutation underlying the condition. Mild forms of usually fatal immunodeficiencies should be considered when assessing the occurrence of unusual infectious diseases in apparently healthy people.

Cytological characterization of an Aspergillus nidulans mutant from a strain with chromosomic duplication

A development mutant, named V103, was obtained spontaneously from the A strain of A. nidulans. The A strain contains a duplicated segment of chromosome I that has undergone translocation to chromosome II (I ¨ II). It is mitotically unstable and generates phenotypically deteriorated types, some with enhanced stability. The deteriorated variants of A. nidulans show abnormal development, exhibiting slower colony growth, variations in colony pigmentation and changes in conidiophore structure. The alterations observed in the conidiophore include fewer metulae and phialides, further elongation and ramification of these structures, delayed nuclear migration and the presence of secondary conidiophores.

Formate-nitrite transporters: optimisation of expression, purification and analysis of prokaryotic and eukaryotic representatives.

The formate-nitrite transporter family is composed of integral membrane proteins that possess six to eight alpha-helical transmembrane domains. Genes encoding these proteins are observed widely in prokaryotic genomes as well as certain groups of lower eukaryotes. Thus far, no structural information is available for this transporter family. Towards this aim, and to provide protein for biophysical studies, overexpression of a prokaryotic (TpNirC, from the hyperthermophilic archaebacterium Thermofilum pendens) and an eukaryotic (AnNitA, from the fungus Aspergillus nidulans) representative was achieved in Escherichia coli and Pichia pastoris hosts, respectively. The proteins were purified to >95% homogeneity yielding quantities sufficient for crystallisation trials and were shown by Circular Dichroism (CD) spectroscopy to have a highly alpha-helical content as expected from in silico predictions. Preliminary investigations by size exclusion chromatography of the oligomeric state of the purified AnNitA protein suggested that it most likely exists as a tetramer.

First case of extensive spinal cord infection with Aspergillus nidulans in a child with chronic granulomatous disease.

Chronic granulomatous disease (CGD) is characterized by a defect in phagocytic cells that lead to recurrent bacterial and fungal infections. The etiology of most common fungal infections in CGD are Aspergillus species. Aspergillus nidulans is one of several species of Aspergillus with low pathogenicity. However, it was reported to cause fatal invasive Aspergillosis in patients with CGD. Here we report the first cured invasive Aspergillus nidulans infection with extensive involvement of the spinal cord in a five-year-old child with CGD.