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1.
An Acad Bras Cienc ; 96(2): e20230826, 2024.
Article in English | MEDLINE | ID: mdl-38747791

ABSTRACT

This study evaluated the nutritional and productive performance of Nellore purebred heifers and crossbred Brangus x Nellore (BGNE) and Braford x Nellore (BFNE) in a feedlot system. Thirty heifers (10 of each genetic group) with an average age of 18 months and an initial body weight of 261 kg were used. The experiment was structured and conducted according to a completely randomized design, with three treatments. Heifers received two diets (60 days each) during the experimental period. The experiment lasted 120 days with four experimental periods. Nellore heifers had a lower intake than crossbred heifers (P <0.05). There were no differences between BGNE and BFNE heifers, which had higher final body weight, average daily gain, feed efficiency, hot carcass weight and carcass length than NE heifers. Crossed heifers presented better fat cover than NE heifers. However, NE heifers had higher carcass dressing Despite presenting lower carcass yields than Nellore heifers, crossed heifers are more efficient and have higher performance and better fat cover on the carcass than purebred Nellore heifers. Crossbreeding synthetic breeds, such as Brangus and Braford breeds, with the Nellore breed is an effective way to increase the productivity and efficiency of feedlot heifers in tropical regions.


Subject(s)
Animal Feed , Animal Nutritional Physiological Phenomena , Animals , Cattle/genetics , Female , Weight Gain/physiology , Body Composition
2.
Cell Rep Med ; 5(5): 101523, 2024 May 21.
Article in English | MEDLINE | ID: mdl-38670098

ABSTRACT

Peritoneal metastases (PMs) from colorectal cancer (CRC) respond poorly to treatment and are associated with unfavorable prognosis. For example, the addition of hyperthermic intraperitoneal chemotherapy (HIPEC) to cytoreductive surgery in resectable patients shows limited benefit, and novel treatments are urgently needed. The majority of CRC-PMs represent the CMS4 molecular subtype of CRC, and here we queried the vulnerabilities of this subtype in pharmacogenomic databases to identify novel therapies. This reveals the copper ionophore elesclomol (ES) as highly effective against CRC-PMs. ES exhibits rapid cytotoxicity against CMS4 cells by targeting mitochondria. We find that a markedly reduced mitochondrial content in CMS4 cells explains their vulnerability to ES. ES demonstrates efficacy in preclinical models of PMs, including CRC-PMs and ovarian cancer organoids, mouse models, and a HIPEC rat model of PMs. The above proposes ES as a promising candidate for the local treatment of CRC-PMs, with broader implications for other PM-prone cancers.


Subject(s)
Colorectal Neoplasms , Mitochondria , Peritoneal Neoplasms , Colorectal Neoplasms/pathology , Colorectal Neoplasms/drug therapy , Peritoneal Neoplasms/secondary , Peritoneal Neoplasms/drug therapy , Peritoneal Neoplasms/therapy , Animals , Humans , Mitochondria/metabolism , Mitochondria/drug effects , Mice , Cell Line, Tumor , Rats , Female , Hyperthermic Intraperitoneal Chemotherapy/methods
3.
IMA Fungus ; 14(1): 20, 2023 Oct 04.
Article in English | MEDLINE | ID: mdl-37794500

ABSTRACT

Sugarcane (Saccharum officinarum, Poaceae) is cultivated on a large scale in (sub)tropical regions such as Brazil and has considerable economic value for sugar and biofuel production. The plant is a rich substrate for endo- and epiphytic fungi. Black yeasts in the family Herpotrichiellaceae (Chaetothyriales) are colonizers of human-dominated habitats, particularly those rich in toxins and hydrocarbon pollutants, and may cause severe infections in susceptible human hosts. The present study assessed the diversity of Herpotrichiellaceae associated with sugarcane, using in silico identification and selective isolation. Using metagenomics, we identified 5833 fungal sequences, while 639 black yeast-like isolates were recovered in vitro. In both strategies, the latter fungi were identified as members of the genera Cladophialophora, Exophiala, and Rhinocladiella (Herpotrichiellaceae), Cyphellophora (Cyphellophoraceae), and Knufia (Trichomeriaceae). In addition, we discovered new species of Cladophialophora and Exophiala from sugarcane and its rhizosphere. The first environmental isolation of Cladophialophora bantiana is particularly noteworthy, because this species up to now is exclusively known from the human host where it mostly causes fatal brain disease in otherwise healthy patients.

4.
STAR Protoc ; 4(4): 102588, 2023 Dec 15.
Article in English | MEDLINE | ID: mdl-37773752

ABSTRACT

Long non-coding RNAs (lncRNAs) are emerging as key regulators in the initiation, growth, and progression of cancer. High-throughput CRISPR-based techniques systematically assess the function of genes or regulatory elements present in the human genome. Here, we present a protocol for identifying essential lncRNAs in cancer using CRISPRi-based dropout screens. We describe steps to select target sites, design guide RNAs, and generate CRISPRi cell lines. We then detail the execution and analysis of CRISPRi-based dropout screens.


Subject(s)
Neoplasms , RNA, Long Noncoding , Humans , CRISPR-Cas Systems/genetics , RNA, Guide, CRISPR-Cas Systems , RNA, Long Noncoding/genetics , Neoplasms/diagnosis , Neoplasms/genetics , Genome, Human
5.
Int J Cancer ; 152(3): 511-523, 2023 02 01.
Article in English | MEDLINE | ID: mdl-36069222

ABSTRACT

Pancreatic ductal adenocarcinoma (PDAC) is characterized by abundant stroma, the main cellular constituents of which are cancer-associated fibroblasts (CAFs). Stroma-targeting agents have been proposed to improve the poor outcome of current treatments. However, clinical trials using these agents showed disappointing results. Heterogeneity in the PDAC CAF population was recently delineated demonstrating that both tumor-promoting and tumor-suppressive activities co-exist in the stroma. Here, we aimed to identify biomarkers for the CAF population that contribute to a favorable outcome. RNA-sequencing reads from patient-derived xenografts (PDXs) were mapped to the human and mouse genome to allocate the expression of genes to the tumor or stroma. Survival meta-analysis for stromal genes was performed and applied to human protein atlas data to identify circulating biomarkers. The candidate protein was perturbed in co-cultures and assessed in existing and novel single-cell gene expression analysis from control, pancreatitis, pancreatitis-recovered and PDAC mouse models. Serum levels of the candidate biomarker were measured in two independent cohorts totaling 148 PDAC patients and related them to overall survival. Osteoglycin (OGN) was identified as a candidate serum prognostic marker. Single-cell analysis indicated that Ogn is derived from a subgroup of inflammatory CAFs. Ogn-expressing fibroblasts are distinct from resident healthy pancreatic stellate cells and arise during pancreatitis. Serum OGN levels were prognostic for favorable overall survival in two independent PDAC cohorts (HR = 0.47, P = .042 and HR = 0.53, P = .006). Altogether, we conclude that high circulating OGN levels inform on a previously unrecognized subgroup of CAFs and predict favorable outcomes in resectable PDAC.


Subject(s)
Cancer-Associated Fibroblasts , Carcinoma, Pancreatic Ductal , Pancreatic Neoplasms , Pancreatitis , Humans , Mice , Animals , Pancreatic Neoplasms/drug therapy , Pancreatic Neoplasms/genetics , Pancreatic Neoplasms/metabolism , Carcinoma, Pancreatic Ductal/drug therapy , Carcinoma, Pancreatic Ductal/genetics , Carcinoma, Pancreatic Ductal/metabolism , Cancer-Associated Fibroblasts/metabolism , Pancreatitis/pathology , Tumor Microenvironment , Pancreatic Neoplasms
6.
Nat Commun ; 13(1): 4443, 2022 08 04.
Article in English | MEDLINE | ID: mdl-35927254

ABSTRACT

A significant proportion of colorectal cancer (CRC) patients develop peritoneal metastases (PM) in the course of their disease. PMs are associated with a poor quality of life, significant morbidity and dismal disease outcome. To improve care for this patient group, a better understanding of the molecular characteristics of CRC-PM is required. Here we present a comprehensive molecular characterization of a cohort of 52 patients. This reveals that CRC-PM represent a distinct CRC molecular subtype, CMS4, but can be further divided in three separate categories, each presenting with unique features. We uncover that the CMS4-associated structural protein Moesin plays a key role in peritoneal dissemination. Finally, we define specific evolutionary features of CRC-PM which indicate that polyclonal metastatic seeding underlies these lesions. Together our results suggest that CRC-PM should be perceived as a distinct disease entity.


Subject(s)
Colorectal Neoplasms , Neoplasms, Second Primary , Peritoneal Neoplasms , Colorectal Neoplasms/pathology , Humans , Peritoneal Neoplasms/genetics , Peritoneal Neoplasms/secondary , Peritoneum/metabolism , Quality of Life
7.
Mol Oncol ; 16(14): 2693-2709, 2022 07.
Article in English | MEDLINE | ID: mdl-35298091

ABSTRACT

Previously, colorectal cancer (CRC) has been classified into four distinct molecular subtypes based on transcriptome data. These consensus molecular subtypes (CMSs) have implications for our understanding of tumor heterogeneity and the prognosis of patients. So far, this classification has been based on the use of messenger RNAs (mRNAs), although microRNAs (miRNAs) have also been shown to play a role in tumor heterogeneity and biological differences between CMSs. In contrast to mRNAs, miRNAs have a smaller size and increased stability, facilitating their detection. Therefore, we built a miRNA-based CMS classifier by converting the existing mRNA-based CMS classification using machine learning (training dataset of n = 271). The performance of this miRNA-assigned CMS classifier (CMS-miRaCl) was evaluated in several datasets, achieving an overall accuracy of ~ 0.72 (0.6329-0.7987) in the largest dataset (n = 158). To gain insight into the biological relevance of CMS-miRaCl, we evaluated the most important features in the classifier. We found that miRNAs previously reported to be relevant in microsatellite-instable CRCs or Wnt signaling were important features for CMS-miRaCl. Following further studies to validate its robustness, this miRNA-based alternative might simplify the implementation of CMS classification in clinical workflows.


Subject(s)
Colorectal Neoplasms , MicroRNAs , Biomarkers, Tumor/genetics , Colorectal Neoplasms/diagnosis , Colorectal Neoplasms/genetics , Colorectal Neoplasms/pathology , Gene Expression Profiling , Humans , MicroRNAs/genetics , Microsatellite Instability , RNA, Messenger/genetics , Transcriptome
8.
Microbes Infect ; 24(4): 104932, 2022 06.
Article in English | MEDLINE | ID: mdl-35032673

ABSTRACT

Subcutaneous phaeohyphomycosis is an implantation disease caused by melanized fungi and affect both immunocompetent as well as immunocompromised individuals. Diagnosis and treatment require proper isolation and accurate identification of the causative pathogen. We isolated a novel fungus from a case of subcutaneous phaeohyphomycosis in an immunocompetent patient. The 56-year-old patient suffered from a slowly progressive swelling on the metatarsophalangeal join of the left food. The isolated fungus lacked sporulation and sequences of the ribosomal operon did not match with any known species. In a multi-locus phylogenetic analysis involving five markers, the fungus formed a unique lineage in the order Pleosporales, family Trematosphaeriaceae. A new genus, Meanderella and a new species, Meanderella rijsii are here proposed to accommodate the clinical isolate. Whole genome analysis of M. rijsii revealed a number of genes that can be linked to pathogenicity and virulence. Further studies are however needed to understand the role of each gene in the pathogenic process and to determine the origin of pathogenicity in the family of Trematosphaeriaceae.


Subject(s)
Ascomycota , Phaeohyphomycosis , Ascomycota/genetics , Humans , Middle Aged , Phaeohyphomycosis/diagnosis , Phaeohyphomycosis/microbiology , Phaeohyphomycosis/pathology , Phylogeny
9.
Braz. arch. biol. technol ; 65: e22210097, 2022. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1364469

ABSTRACT

Abstract: Cerrado is the second largest biome in Brazil and majorly contributes to the country's grain production. Previous studies on soil metagenomics from the Cerrado revealed an outstanding microbial diversity. In this study, the abundance of pathogenic fungi was analyzed using metagenomic sequences of the Cerrado soils under native vegetation, and under agriculture with no-tillage and conventional tillage. In total, 128,627 sequences of fungi were identified, with 43,439 representing pathogenic fungi and were distributed as follows: native 17,301 (40%), no-tillage 13,780 (32%), and conventional tillage 12,358 (28%). We identified 41 pathogenic fungal species associated with human and animal infections. The data analysis revealed that the native soils had a higher relative abundance of fungal sequences, similar to pathogenic species sequences, in relation to the total eukaryotic sequences, than the conventional tillage and no-tillage treatments, which observed a reduction in fungal abundance because of anthropogenic activities.

10.
Cell Stem Cell ; 28(11): 2009-2019.e4, 2021 11 04.
Article in English | MEDLINE | ID: mdl-34358441

ABSTRACT

The tissue dynamics that govern maintenance and regeneration of the pancreas remain largely unknown. In particular, the presence and nature of a cellular hierarchy remains a topic of debate. Previous lineage tracing strategies in the pancreas relied on specific marker genes for clonal labeling, which left other populations untested and failed to account for potential widespread phenotypical plasticity. Here we employed a tracing system that depends on replication-induced clonal marks. We found that, in homeostasis, steady acinar replacement events characterize tissue dynamics, to which all acinar cells have an equal ability to contribute. Similarly, regeneration following pancreatitis was best characterized by an acinar self-replication model because no evidence of a cellular hierarchy was detected. In particular, rapid regeneration in the pancreas was found to be driven by an accelerated rate of acinar fission-like events. These results provide a comprehensive and quantitative model of cell dynamics in the exocrine pancreas.


Subject(s)
Pancreas, Exocrine , Pancreatitis , Acinar Cells , Homeostasis , Humans , Pancreas
11.
Med Oncol ; 38(9): 105, 2021 Jul 31.
Article in English | MEDLINE | ID: mdl-34331598

ABSTRACT

Renal cell carcinoma (RCC) accounts for over 400,000 new cases and 175,000 deaths annually. Diagnostic RCC biomarkers may prevent overtreatment in patients with early disease. Extracellular vesicles (EVs) are a promising source of RCC biomarkers because EVs carry proteins and messenger RNA (mRNA) among other biomolecules. We aimed to identify biomarkers and assess biological functions of EV cargo from clear cell RCC (ccRCC), papillary RCC (pRCC), and benign kidney cell lines. EVs were enriched from conditioned cell media by size exclusion chromatography. The EV proteome was assessed using Tandem Mass Tag mass spectrometry (TMT-MS) and NanoString nCounter technology was used to profile 770 cancer-related mRNA present in EVs. The heterogeneity of protein and mRNA abundance and identification highlighted the heterogeneity of EV cargo, even between cell lines of a similar pathological group (e.g., ccRCC or pRCC). Overall, 1726 proteins were quantified across all EV samples, including 181 proteins that were detected in all samples. In the targeted profiling of mRNA by NanoString, 461 mRNAs were detected in EVs from at least one cell line, including 159 that were present in EVs from all cell lines. In addition to a shared EV cargo signature, pRCC, ccRCC, and/or benign renal cell lines also showed unique signatures. Using this multi-omics approach, we identified 34 protein candidate pRCC EV biomarkers and 20 protein and 8 mRNA candidate ccRCC EV biomarkers for clinical validation.


Subject(s)
Carcinoma, Papillary/diagnosis , Carcinoma, Renal Cell/diagnosis , Extracellular Vesicles/metabolism , Kidney Neoplasms/diagnosis , Kidney/pathology , Proteome/metabolism , Transcriptome , Apoptosis , Biomarkers, Tumor/genetics , Biomarkers, Tumor/metabolism , Carcinoma, Papillary/genetics , Carcinoma, Papillary/metabolism , Carcinoma, Renal Cell/genetics , Carcinoma, Renal Cell/metabolism , Cell Proliferation , Diagnosis, Differential , Extracellular Vesicles/genetics , Gene Expression Regulation, Neoplastic , Humans , In Vitro Techniques , Kidney/metabolism , Kidney Neoplasms/genetics , Kidney Neoplasms/metabolism , Proteome/analysis , RNA, Messenger/genetics , RNA, Messenger/metabolism , Tumor Cells, Cultured
12.
Nature ; 594(7863): 436-441, 2021 06.
Article in English | MEDLINE | ID: mdl-34079128

ABSTRACT

A delicate equilibrium of WNT agonists and antagonists in the intestinal stem cell (ISC) niche is critical to maintaining the ISC compartment, as it accommodates the rapid renewal of the gut lining. Disruption of this balance by mutations in the tumour suppressor gene APC, which are found in approximately 80% of all human colon cancers, leads to unrestrained activation of the WNT pathway1,2. It has previously been established that Apc-mutant cells have a competitive advantage over wild-type ISCs3. Consequently, Apc-mutant ISCs frequently outcompete all wild-type stem cells within a crypt, thereby reaching clonal fixation in the tissue and initiating cancer formation. However, whether the increased relative fitness of Apc-mutant ISCs involves only cell-intrinsic features or whether Apc mutants are actively involved in the elimination of their wild-type neighbours remains unresolved. Here we show that Apc-mutant ISCs function as bona fide supercompetitors by secreting WNT antagonists, thereby inducing differentiation of neighbouring wild-type ISCs. Lithium chloride prevented the expansion of Apc-mutant clones and the formation of adenomas by rendering wild-type ISCs insensitive to WNT antagonists through downstream activation of WNT by inhibition of GSK3ß. Our work suggests that boosting the fitness of healthy cells to limit the expansion of pre-malignant clones may be a powerful strategy to limit the formation of cancers in high-risk individuals.


Subject(s)
Adenomatous Polyposis Coli Protein/genetics , Cell Competition , Genes, APC , Intestinal Neoplasms/genetics , Intestinal Neoplasms/pathology , Mutation , Adenoma/genetics , Adenoma/metabolism , Adenoma/pathology , Adenomatous Polyposis Coli Protein/deficiency , Animals , Cell Differentiation/genetics , Female , Glycogen Synthase Kinase 3 beta/antagonists & inhibitors , Humans , Intestinal Neoplasms/metabolism , Lithium Chloride/pharmacology , Male , Mice , Organoids/cytology , Organoids/metabolism , Organoids/pathology , Wnt Proteins/antagonists & inhibitors , Wnt Proteins/metabolism
13.
J Fungi (Basel) ; 7(2)2021 Jan 29.
Article in English | MEDLINE | ID: mdl-33572699

ABSTRACT

Chromoblastomycosis is a chronic severely mutilating disease caused by fungi of the order Chaetothyriales. Classically, Phialophora verrucosa has been listed among these etiologic agents. This species is known to occur in the environment and has been found to cause other infections like phaeohyphomycosis, while reported cases of chromoblastomycosis are scant. Phialophora is phylogenetically diverse, and thus retrospective confirmation of etiology is necessary. We studied ten proven cases of chromoblastomycosis from Mexico and further analyzed the population genetics and genomics of the Phialophora species to understand their pathogenicity and predilection. The clinical strains were molecularly identified as Phialophora americana (n = 4), Phialophorachinensis (n = 4), and Phialophora macrospora (n = 2). No genetic distinction between clinical and environmental strains was possible. Further analysis of strains from diverse origins are needed to address eventual differences in virulence and niche predilection between the species.

14.
Front Genet ; 11: 822, 2020.
Article in English | MEDLINE | ID: mdl-32849816

ABSTRACT

Among agents of chromoblastomycosis, Fonsecaea pugnacius presents a unique type of infection because of its secondary neurotropic dissemination from a chronic cutaneous case in an immunocompetent patient. Neurotropism occurs with remarkable frequency in the fungal family Herpotrichiellaceae, possibly associated with the ability of some species to metabolize aromatic hydrocarbons. In an attempt to understand this new disease pattern, were conducted genomic analysis of Fonsecaea pugnacius (CBS 139214) performed with de novo assembly, gene prediction, annotation and mitochondrial genome assembly, supplemented with animal infection models performed with Tenebrio molitor in Mus musculus lineages BALB/c and C57BL/6. The genome draft of 34.8 Mb was assembled with a total of 12,217 protein-coding genes. Several proteins, enzymes and metabolic pathways related to extremotolerance and virulence were recognized. The enzyme profiles of black fungi involved in chromoblastomycosis and brain infection were analyzed with the Carbohydrate-Active Enzymes (CAZY) and peptidases database (MEROPS). The capacity of the fungus to survive inside Tenebrio molitor animal model was confirmed by histopathological analysis and by presence of melanin and hyphae in host tissue. Although F. pugnacius was isolated from brain in a murine model following intraperitoneal infection, cytokine levels were not statistically significant, indicating a profile of an opportunistic agent. A dual ecological ability can be concluded from presence of metabolic pathways for nutrient scavenging and extremotolerance, combined with a capacity to infect human hosts.

15.
Sci Rep ; 10(1): 14229, 2020 08 26.
Article in English | MEDLINE | ID: mdl-32848176

ABSTRACT

Melanized fungi and black yeasts in the family Herpotrichiellaceae (order Chaetothyriales) are important agents of human and animal infectious diseases such as chromoblastomycosis and phaeohyphomycosis. The oligotrophic nature of these fungi enables them to survive in adverse environments where common saprobes are absent. Due to their slow growth, they lose competition with common saprobes, and therefore isolation studies yielded low frequencies of clinically relevant species in environmental habitats from which humans are thought to be infected. This problem can be solved with metagenomic techniques which allow recognition of microorganisms independent from culture. The present study aimed to identify species of the family Herpotrichiellaceae that are known to occur in Brazil by the use of molecular markers to screen public environmental metagenomic datasets from Brazil available in the Sequence Read Archive (SRA). Species characterization was performed with the BLAST comparison of previously described barcodes and padlock probe sequences. A total of 18,329 sequences was collected comprising the genera Cladophialophora, Exophiala, Fonsecaea, Rhinocladiella and Veronaea, with a focus on species related to the chromoblastomycosis. The data obtained in this study demonstrated presence of these opportunists in the investigated datasets. The used techniques contribute to our understanding of environmental occurrence and epidemiology of black fungi.


Subject(s)
Ascomycota/isolation & purification , Chromoblastomycosis/microbiology , Ascomycota/genetics , Brazil , Datasets as Topic , Environmental Monitoring/methods , Humans , Metagenomics
16.
Front Microbiol ; 11: 586, 2020.
Article in English | MEDLINE | ID: mdl-32373085

ABSTRACT

The two black yeasts Exophiala dermatitidis and Exophiala spinifera that are clinically considered as the most virulent species potentially causing disseminated infections are both producing extracellular capsule-like material, are compared. In this study, 10 genomes of E. spinifera and E. dermatitidis strains, including both clinical and environmental isolates, were selected based on phylogenetic analysis, physiology tests and virulence tests, sequenced on the Illumina MiSeq sequencer and annotated. Comparison of genome data were performed between intraspecific and interspecific strains. We found capsule-associated genes were however not consistently present in both species by the comparative genomics. The prevalent clinical species, E. dermatitidis, has small genomes containing significantly less virulence-associated genes than E. spinifera, and also than saprobic relatives. Gene OG0012246 and Myb-like DNA-binding domain and SANT/Myb domain, restricted to two strains from human brain, was shared with the neurotropic species Rhinocladiella mackenziei. This study indicated that different virulence profiles existed in the two capsule-producing black yeasts, and the absence of consistent virulence-associated profiles supports the hypothesis that black yeasts are opportunists rather than primary pathogens. The results also provide the key virulence genes and drive the continuing research forward pathogen-host interactions to explore the pathogenesis.

17.
G3 (Bethesda) ; 10(6): 1817-1821, 2020 06 01.
Article in English | MEDLINE | ID: mdl-32238422

ABSTRACT

The black yeast-like fungus Arthrocladium fulminans is known from strains that cause severe and eventually fatal disseminated infections in immunocompromised patients. Given the dramatic outcome of this clinical case, it is essential to understand the virulence potential of this species. The fungus is a member of the family Trichomeriaceae, at some phylogenetic distance from the Herpotrichiellaceae where most infectious fungi in the order Chaetothyriales are located. Main ecological preferences among Trichomeriaceae include colonization of exposed inert surfaces. Currently, black yeasts genomes that are available in public databases cover members of the families Herpotrichiellaceae and Cyphellophoraceae In the present report, we sequenced the genome of the first member and only clinical representative of the family Trichomeriaceae.


Subject(s)
Ascomycota , Ascomycota/genetics , Humans , Phylogeny
18.
Fungal Biol ; 124(3-4): 194-204, 2020.
Article in English | MEDLINE | ID: mdl-32220380

ABSTRACT

Chromoblastomycosis is a neglected disease characterized by cutaneous, subcutaneous or disseminated lesions. It is considered an occupational infectious disease that affects mostly rural workers exposed to contaminated soil and vegetal matter. Lesions mostly arise after a traumatic inoculation of herpotrichiellaceous fungi from the Chaetothyriales order. However, the environmental niche of the agents of the disease remains obscure. Its association with insects has been predicted in a few studies. Therefore, the present work aimed to analyze if social insects, specifically ants, bees, and termites, provide a suitable habitat for the fungi concerned. The mineral oil flotation method was used to isolate the microorganisms. Nine isolates were recovered and phylogenetic analysis identified two strains as potential agents of chromoblastomycosis, i.e., Fonsecaea pedrosoi CMRP 3076, obtained from a termite nest (n = 1) and Rhinocladiella similis CMRP 3079 from an ant exoskeleton (n = 1). In addition, we also identified Fonsecaea brasiliensis CMRP 3445 from termites (n = 1), Exophiala xenobiotica CMRP 3077 from ant exoskeleton (n = 1), Cyphellophoraceae CMRP 3103 from bees (n = 1), Cladosporium sp. CMRP 3119 from bees (n = 1), Hawksworthiomyces sp. CMRP 3102 from termites (n = 1), and Cryptendoxyla sp. from termites (n = 2). The environmental isolate of F. pedrosoi CMRP 3076 was tested in two animal models, Tenebrio molitor and Wistar rat, for its pathogenic potential with fungal retention in T. molitor tissue. In the Wistar rat, the cells resembling muriform cells were observed 30 d after inoculation.


Subject(s)
Ascomycota , Chromoblastomycosis/microbiology , Disease Reservoirs/microbiology , Animals , Ants/microbiology , Ascomycota/genetics , Ascomycota/isolation & purification , Bees/microbiology , Cladosporium/genetics , Cladosporium/isolation & purification , Fonsecaea/genetics , Fonsecaea/isolation & purification , Genes, Fungal , Humans , Insecta , Isoptera/microbiology , Models, Animal , Pathology, Molecular , Phylogeny , Rats , Rats, Wistar/microbiology , Soil Microbiology , Tenebrio/microbiology
19.
Fungal Genet Biol ; 138: 103351, 2020 05.
Article in English | MEDLINE | ID: mdl-32028048

ABSTRACT

Modern genome analysis and phylogenomic methods have increased the number of fungal species, as well as enhanced appreciation of the degree of diversity within the fungal kingdom. In this context, we describe a new Parengyodontium species, P. americanum, which is phylogenetically related to the opportunistic human fungal pathogen P. album. Five unusual fungal isolates were recovered from five unique and confirmed coccidioidomycosis patients, and these isolates were subsequently submitted to detailed molecular and morphological identification procedures to determine identity. Molecular and morphological diagnostic analyses showed that the isolates belong to the Cordycipitaceae. Subsequently, three representative genomes were sequenced and annotated, and a new species, P. americanum, was identified. Using various genomic analyses, gene family expansions related to novel compounds and potential for ability to grow in diverse habitats are predicted. A general description of the genomic composition of this newly described species and comparison of genome content with Beauveria bassiana, Isaria fumosorosea and Cordyceps militaris shows a shared core genome of 6371 genes, and 148 genes that appear to be specific for P. americanum. This work provides the framework for future investigations of this interesting fungal species.


Subject(s)
Coccidioidomycosis/microbiology , Hypocreales , Beauveria/genetics , Cordyceps/genetics , Fungal Proteins/genetics , Genome, Fungal , Humans , Hypocreales/classification , Hypocreales/cytology , Hypocreales/genetics , Hypocreales/isolation & purification , Opportunistic Infections/microbiology , Phylogeny , Proteomics
20.
BMC Genomics ; 21(1): 134, 2020 Feb 10.
Article in English | MEDLINE | ID: mdl-32039705

ABSTRACT

BACKGROUND: Herbaspirillum seropedicae is a diazotrophic bacterium from the ß-proteobacteria class that colonizes endophytically important gramineous species, promotes their growth through phytohormone-dependent stimulation and can express nif genes and fix nitrogen inside plant tissues. Due to these properties this bacterium has great potential as a commercial inoculant for agriculture. The H. seropedicae SmR1 genome is completely sequenced and annotated but despite the availability of diverse structural and functional analysis of this genome, studies involving small non-coding RNAs (sRNAs) has not yet been done. We have conducted computational prediction and RNA-seq analysis to select and confirm the expression of sRNA genes in the H. seropedicae SmR1 genome, in the presence of two nitrogen independent sources and in presence of naringenin, a flavonoid secreted by some plants. RESULTS: This approach resulted in a set of 117 sRNAs distributed in riboswitch, cis-encoded and trans-encoded categories and among them 20 have Rfam homologs. The housekeeping sRNAs tmRNA, ssrS and 4.5S were found and we observed that a large number of sRNAs are more expressed in the nitrate condition rather than the control condition and in the presence of naringenin. Some sRNAs expression were confirmed in vitro and this work contributes to better understand the post transcriptional regulation in this bacterium. CONCLUSIONS: H. seropedicae SmR1 express sRNAs in the presence of two nitrogen sources and/or in the presence of naringenin. The functions of most of these sRNAs remains unknown but their existence in this bacterium confirms the evidence that sRNAs are involved in many different cellular activities to adapt to nutritional and environmental changes.


Subject(s)
Gene Expression Regulation, Bacterial , Herbaspirillum/genetics , Nitrates/metabolism , Nitrogen Fixation/genetics , RNA, Bacterial/genetics , RNA, Small Untranslated/genetics , Computer Simulation , Flavanones/metabolism , Flavanones/pharmacology , Herbaspirillum/drug effects , Nitrates/pharmacology , Riboswitch
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