RESUMO
Caves are unique environments characterized by spatial limitations, partial or total absence of direct light, and scarcity of organic carbon and nutrients. Caves are shelters for a variety of adapted animals and microorganisms such as fungi, many of which are still unknown. Amphichorda is a fungal genus belonging to the family Bionectriaceae, which includes cave-dwelling and entomopathogenic species with biotechnological applications. In this study, a new fungal species was identified using morphological and multi-locus phylogenetic analyses of the ITS, LSU, and TEF loci, in the Gruta Velha Nova limestone cave located in the Southern Espinhaço Range, Monjolos, Minas Gerais, Brazil. During the exposure of potato dextrose agar plates to the cave environment, an insect from the family Rhaphidophoridae passed by and fed on the culture medium, resulting in three fungal isolates. Phylogenetic analyses showed that these isolates formed a clade distinct from all known species, leading us to introduce a new species, Amphichorda monjolensis, which may be associated with this insect. Here, we also proposed two new combinations for species of acremonium-like fungi in the Bionectriaceae: Bulbithecium globosisporum (synonym: Acremonium globosisporum) and Hapsidospora curva (synonym: Acremonium curvum). The discovery of A. monjolensis highlights the potential of caves as shelters for new species with significant biotechnological importance.
Assuntos
Cavernas , DNA Fúngico , Filogenia , Cavernas/microbiologia , Brasil , DNA Fúngico/genética , Animais , Carbonato de Cálcio , Acremonium/genética , Acremonium/classificação , Acremonium/isolamento & purificaçãoRESUMO
Changes in the spectrum of clinically important fungal infection have been observed in recent years. Acremonium species has been responsible for eumycotic mycetomas but has also been increasingly implicated in systemic fungal diseases. A case of Acremonium kiliense fungemia with proven involvement of the lungs in an allogeneic hematopoietic stem cell patient is reported. A high-resolution computed tomography scan of the lungs showed nodules in both lungs. Multiple cultures of blood demonstrated narrow septate hyphae, cylindrical conidia, and solitary tapering phialides and microconidia that remained grouped in slimy heads. The isolate was identified as A. kiliense based on its morphological characteristics and DNA sequence analysis. Susceptibility testing of the clinical isolate was performed to four antifungal agents. Amphotericin B, fluconazole and itraconazole were found to be inactive in vitro against the isolate; however, it was found to be sensitive to voriconazole. This last drug was indicated, and a high-resolution computed tomography scan of the lungs was normal after 10 days. One year later, the patient was free of symptoms and her blood culture was negative for fungi. Thus, voriconazole was effective in treatment for life-threatening A. kiliense infections. In this work, we performed an overview of worldwide clinical infections caused by A. kiliense.
Assuntos
Acremonium/isolamento & purificação , Fungemia/diagnóstico , Fungemia/microbiologia , Pneumopatias Fúngicas/diagnóstico , Pneumopatias Fúngicas/microbiologia , Acremonium/classificação , Acremonium/citologia , Adulto , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , DNA Fúngico/química , DNA Fúngico/genética , DNA Ribossômico/química , DNA Ribossômico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Feminino , Fungemia/complicações , Transplante de Células-Tronco Hematopoéticas , Humanos , Hospedeiro Imunocomprometido , Pulmão/patologia , Pneumopatias Fúngicas/complicações , Técnicas Microbiológicas , Microscopia , RNA Ribossômico 5,8S/genética , Radiografia Torácica , Análise de Sequência de DNA , Tomografia Computadorizada por Raios X , Transplante , Transplante HomólogoRESUMO
The objective of the present study was to evaluate the production of cellulolytic enzymes by Acremonium strictum isolated from Brazilian Biome using different substrates. Fermentations were initially carried out using commercial substrates, including microcrystalline cellulose (AVICEL® and SERVACEL®) and carboxymethylcellulose (CMC). This was followed by fermentations performed using lignocellulosic biomass: sugarcane bagasse pretreated at different intensities. The fermentations were carried out in shakers at 150 rpm, 30 °C for 240 h. Four enzyme activities were determined: CMCase, FPase, cellobiase and ß-glucosidase. Among the substrates used, results showed that the sugarcane bagasse submitted to mild pretreatment was that which induced the microorganism to produce greater cellulolytic activities. This substrate was employed in the optimization study of cellulase production by A. strictum.
Assuntos
Acremonium/enzimologia , Acremonium/isolamento & purificação , Celulase/química , Celulase/metabolismo , Acremonium/classificação , Brasil , Celulase/isolamento & purificação , Ativação Enzimática , Estabilidade Enzimática , Especificidade da Espécie , Especificidade por SubstratoRESUMO
En este estudio se realizaron los primeros aislamientos del estado asexual del patógeno Neonectria fuckeliana asociado a cancros o ®revirado del pino¼ en plantaciones de Pinus radiata. Se caracterizaron morfológicamente las cepas del sinanamorfo semejante a Verticillium (Acremonium), obtenidas en cultivo in vitro a partir de peritecios. El material para los aislamientos consistió en trozos de corteza de P. radiata con presencia de peritecios, colectados en Toltén, región de La Araucanía, lugar donde se realizó el primer reporte de N. fuckeliana en Chile. Se utilizaron diez cepas del semejante a Acremonium para la caracterización morfológica, mediciones de estructuras fúngicas, ritmo de crecimiento in vitro y morfología de las colonias. Las colonias presentaron un micelio flocoso y ralo de bordes blanquecinos e irregulares, destacándose tres tipos de colonias, blancas, naranjo oscura y naranjo claro. Taxonómicamente, las cepas coinciden con las estructuras mencionadas en la literatura, caracterizándose por la presencia de glioconidios. Las fialides midieron entre 7 78,4 x 1,4 - 4,9 ìm. Los conidios, de formas ovoides y algunas bicelulares, midieron entre 4,2 - 8,4 x 2,6 - 3,5 ìm. El ritmo de crecimiento in vitro fue lento, completando su desarrollo a los 19 días con un promedio de 71 +/- 0,3 mm de diámetro, a una tasa de crecimiento diario de 3,8 mm. Los resultados obtenidos hacen necesario futuros estudios de carácter molecular para analizar la variabilidad genética poblacional que puede presentarse en Chile.
First Neonectria fuckeliana isolates in Chile. Strains of Acremonium obtained from in vitro peritecia culture were morphologically characterized. The samples were collected in Toltén, La Araucanía region, were Neonectria fuckeliana was first reported in Chile. The material used for the isolation came from pieces of Pinus radiata bark with peritecia. Ten Acremonium-like strains were used for characterization of fungal structures, in vitro growth and strains morphology. The colonies were a floccose mycelium and thin edges whitish and irregular, varying color highlighting three types of strains, white, dark orange and pale orange. Taxonomically, the strains match the structures referred in the literature, characterized by the presence of gliospores. The phialides dimensions ranged from 7 to 7.8 ìm long and 1.4 to 4.9 ìm wide. The conidio of ovoid shapes and some bicelular measured between 4.2 to 8.4 ìm in length and width 2.6 and 3.5 ìm. In vitro growth rates were slow, the complete development take19 days with a daily growth average of 71 +/-3 mm in diameter, at a rate of 3.8 mm. It is necessary future molecular studies to analyze the population genetic variation that may occur in Chile.
Assuntos
Acremonium/isolamento & purificação , Acremonium/classificação , Acremonium/crescimento & desenvolvimento , Acremonium/patogenicidade , Fungos/crescimento & desenvolvimento , Pinus/crescimento & desenvolvimento , Pinus/microbiologia , ChileRESUMO
Hydrolytic enzymes secreted by fungi play an important role in the pathogenesis of infection. With the aim of evaluating the enzymatic activity, 31 isolates of Acremonium stored in the University of Recife Mycology (URM) Culture Collection were tested. Culture fragments were transferred to glycoside broth for reactivation and further growth in potato dextrose agar medium in order to investigate viability and purity and to confirm the taxonomy through observing the macroscopic and microscopic characteristics. To detect enzymes, milk casein and gelatin were used as substrates for proteinase, starch for amylase and soy lecithin for phospholipase. Among the 31 cultures, 26 (83.9%) remained viable and 24 (92.3%) were confirmed taxonomically. Out of these 24 cultures, 12 (50%) presented proteinase activity, of which two (16.7%) were on milk casein, one (8.3%) on gelatin and nine (75%) on both substrates; 16 (66.7%) degraded starch. None of the cultures presented phospholipase activity. It was concluded that Acremonium species are able to produce enzymes that are involved in the pathogenicity of fungal infections.
Assuntos
Acremonium/enzimologia , Amilases/biossíntese , Peptídeo Hidrolases/biossíntese , Fosfolipases/biossíntese , Acremonium/classificação , Acremonium/crescimento & desenvolvimento , Óleo Mineral , Preservação Biológica/métodosRESUMO
Enzimas hidrolíticas secretadas por fungos têm um papel importante na patogenicidade das infecções. Objetivando avaliar a atividade enzimática foram testados 31 isolados de Acremonium mantidos na Coleção de Culturas University Recife Mycology. Fragmentos das culturas foram transferidos para caldo glicosado para reativação e posterior crescimento em meio ágar batata dextrose, para verificar viabilidade, pureza e confirmação taxonômica pela observação das características macroscópicas e microscópicas. Para detecção enzimática foram utilizados substratos de caseína do leite e gelatina para protease, amido para amilase e lecitina de soja para fosfolipase. Das 31 culturas, 26 (83,9 por cento) mantiveram-se viáveis e 24 (92,3 por cento) foram confirmadas taxonomicamente. Das 24 culturas, 12 (50 por cento) apresentaram atividade proteásica, duas (16,7 por cento) em caseína do leite, uma (8,3 por cento) em gelatina e nove (75 por cento) em ambos os substratos; 16 (66,7 por cento) degradaram amido. Nenhuma cultura apresentou atividade fosfolipásica. Conclui-se que espécies de Acremonium são capazes de produzir enzimas envolvidas na patogenicidade das infecções fúngicas.
Hydrolytic enzymes secreted by fungi play an important role in the pathogenesis of infection. With the aim of evaluating the enzymatic activity, 31 isolates of Acremonium stored in the University of Recife Mycology (URM) Culture Collection were tested. Culture fragments were transferred to glycoside broth for reactivation and further growth in potato dextrose agar medium in order to investigate viability and purity and to confirm the taxonomy through observing the macroscopic and microscopic characteristics. To detect enzymes, milk casein and gelatin were used as substrates for proteinase, starch for amylase and soy lecithin for phospholipase. Among the 31 cultures, 26 (83.9 percent) remained viable and 24 (92.3 percent) were confirmed taxonomically. Out of these 24 cultures, 12 (50 percent) presented proteinase activity, of which two (16.7 percent) were on milk casein, one (8.3 percent) on gelatin and nine (75 percent) on both substrates; 16 (66.7 percent) degraded starch. None of the cultures presented phospholipase activity. It was concluded that Acremonium species are able to produce enzymes that are involved in the pathogenicity of fungal infections.
Assuntos
Acremonium/enzimologia , Amilases/biossíntese , Peptídeo Hidrolases/biossíntese , Fosfolipases/biossíntese , Acremonium/classificação , Acremonium/crescimento & desenvolvimento , Óleo Mineral , Preservação Biológica/métodosRESUMO
Brachiaria, predominantly an African genus, contains species, such as B. brizantha, an apomictic C4 grass, that are commercially important forage grasses in tropical America, where they now cover about 55 million hectares. From B. brizantha accession CIAT 6780, we isolated an endophytic fungus that may be economically significant. The fungus was identified as Acremonium implicatum (J. Gilman & E.V. Abott). 18S rDNA and ITS rDNA sequences were used to characterize isolates of the endophyte, and showed that they belonged to the Acremonium genus, being close to A. strictum and A. kiliense. Using the random amplified polymorphic DNA (RAPD) technique, involving arbitrary primers of 10 bases, we showed that the isolates were highly similar to each other. Antiserum produced from a monoconidial culture of A. implicatum isolated from B. brizantha 6780, differentiated the isolates consistently in line with the DNA data. When we compared endophyte-free with endophyte-infected B. brizantha CIAT 6780 plants, both artificially inoculated with the pathogenic Drechslera fungus, we found that the endophyte-infected plants had fewer and smaller lesions than did the endophyte-free plants. Sporulation of Drechslera sp. on artificially inoculated leaf sheath tissues was also much less on tissue infected with the endophyte.
Assuntos
Acremonium/classificação , Acremonium/isolamento & purificação , Brachiaria/microbiologia , Acremonium/fisiologia , Antibiose , Ascomicetos/crescimento & desenvolvimento , Ascomicetos/patogenicidade , Impressões Digitais de DNA , DNA Fúngico/química , DNA Fúngico/isolamento & purificação , DNA Ribossômico/química , DNA Ribossômico/isolamento & purificação , Filogenia , Doenças das Plantas/microbiologia , Folhas de Planta/microbiologia , Polimorfismo Genético , RNA Ribossômico 18S/genética , Técnica de Amplificação ao Acaso de DNA Polimórfico , Análise de Sequência de DNA , Sorotipagem , SimbioseRESUMO
Os autores registram caso de hialo-hifomicose subcutanea por Acremonium recifei em paciente branca, imunocompetente, natural da Bahia, com historia de traumatismo no dorso da mao direita. A lesao era indolor, com edema, inflamacao, presenca de fistulas, secrecao seropulenta, e ausencia de graos. O exame histopatologico mostrou hifas septadas hialinas pela hematoxilina-eosina...