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Molecules (Basel, Switzerland) Jun 2021Redox-active drugs are the mainstay of parasite chemotherapy. To assess their repurposing potential for eumycetoma, we have tested a set of nitroheterocycles and...
Redox-active drugs are the mainstay of parasite chemotherapy. To assess their repurposing potential for eumycetoma, we have tested a set of nitroheterocycles and peroxides in vitro against two isolates of , the main causative agent of eumycetoma in Sudan. All the tested compounds were inactive except for niclosamide, which had minimal inhibitory concentrations of around 1 µg/mL. Further tests with niclosamide and niclosamide ethanolamine demonstrated in vitro activity not only against but also against spp., causative agents of actinomycetoma, with minimal inhibitory concentrations below 1 µg/mL. The experimental compound MMV665807, a related salicylanilide without a nitro group, was as active as niclosamide, indicating that the antimycetomal action of niclosamide is independent of its redox chemistry (which is in agreement with the complete lack of activity in all other nitroheterocyclic drugs tested). Based on these results, we propose to further evaluate the salicylanilides, niclosamidein particular, as drug repurposing candidates for mycetoma.
Topics: Actinomadura; Animals; Humans; Madurella; Mycetoma; Niclosamide
PubMed: 34209118
DOI: 10.3390/molecules26134005 -
Frontiers in Microbiology 2021, an important Chinese medicinal herb, can be mainly cultivated in two planting patterns, cropland planting (DT) and understory planting (LX). We speculate that the...
, an important Chinese medicinal herb, can be mainly cultivated in two planting patterns, cropland planting (DT) and understory planting (LX). We speculate that the rhizosphere microbiome may vary in DT and LX and may play an important role in promoting the growth and health of . In the present study, culture-independent Illumina HiSeq was employed to investigate the rhizosphere bacteria and fungi under DT and LX planting patterns. Predominant phyla include , , , , and in the two planting patterns. DT has higher alpha diversity index than LX. The predominant LX-core genera include , , and the predominant DT-core genera include , , and . Total relative abundance of the disease-suppression phylum (, , and ) and the potential plant growth-promoting rhizobacteria (PGPR) were both significantly higher in LX than in DT. We also identified over-presented microbial functional traits mediating plant-microbe and microbe-microbe interactions, nutrition acquisition, and plant growth promotion in rhizosphere. Our findings provide a valuable reference for studying beneficial microbes and pathogens of planted in DT and LX.
PubMed: 34177857
DOI: 10.3389/fmicb.2021.673512 -
Ecotoxicology and Environmental Safety Sep 2021Aerobic composting is commonly used to dispose livestock manure and is an efficient way to reduce antibiotic resistance genes (ARGs). Here, the effects of different...
Aerobic composting is commonly used to dispose livestock manure and is an efficient way to reduce antibiotic resistance genes (ARGs). Here, the effects of different quality substrates on the fate of ARGs were assessed during manure composting. Results showed that the total relative abundances of ARGs and intI1 in additive treatments were lower than that in control, and high quality treatment with low C/N ratio and lignin significantly decreased the relative abundance of tetW, ermB, ermC, sul1 and sul2 at the end of composting. Additionally, higher quality treatment reduced the relative abundances of some pathogens such as Actinomadura and Pusillimonas, and some thermotolerant degrading-related bacteria comprising Pseudogracilibacillus and Sinibacillus on day 42, probably owing to the change of composting properties in piles. Structural equation models (SEMs) further verified that the physiochemical properties of composting were the dominant contributor to the variations in ARGs and they could also indirectly impact ARGs by influencing bacterial community and the abundance of intI1. Overall, these findings indicated that additives with high quality reduced the reservoir of antibiotic resistance genes of livestock manure compost.
Topics: Animals; Bacteria; Carbon; Chickens; Composting; Drug Resistance, Microbial; Genes, Bacterial; Lignin; Manure; Microbiota; Nitrogen
PubMed: 34139628
DOI: 10.1016/j.ecoenv.2021.112413 -
Indian Dermatology Online Journal 2021Mycetoma is a chronic, granulomatous disease caused by fungi (eumycetoma) or aerobic filamentous actinomycetes (actinomycetoma). is one of the most frequent...
CONTEXT
Mycetoma is a chronic, granulomatous disease caused by fungi (eumycetoma) or aerobic filamentous actinomycetes (actinomycetoma). is one of the most frequent actinomycetes.
AIM
The study aims to provide an update on clinical, diagnostic, therapeutic, and outcome data for patients with actinomycetoma in a single center in Mexico.
SETTINGS AND DESIGN
This was a retrospective study of 47 cases diagnosed with actinomycetoma.
SUBJECTS AND METHODS
The cases were selected from a total of 536 mycetoma obtained during 35 years (from 1985 to 2019). Clinical data were retrieved from the clinical records of our department. Microbiological data were obtained from our Mycology laboratory.
STATISTICAL ANALYSIS
Frequencies and percentages were used for categorical variables. Normality was determined with the Kolmogorov-Smirnov test. We used means and medians to describe the variables.
RESULTS
Forty-seven patients with actinomycetoma were included; female:male ratio 1.9:1; median age 38 years. The foot was the most affected region in 76.5% of cases. The bone invasion was observed in 89%. The time between symptoms onset and diagnosis was 5.5 years. Grain detection by direct examination was positive in 95% of cases. The most commonly used, as well as the most effective treatment scheme was streptomycin + sulfamethoxazole-trimethoprim with dapsone. Sixty-three percent (30 patients) achieved clinical and mycological cure, and 10.6% (5 patients) had treatment failure.
CONCLUSIONS
We highlight the importance of designing therapeutic strategies to standardize treatments and gain more experience to improve the care of these patients.
PubMed: 33959526
DOI: 10.4103/idoj.IDOJ_474_20 -
MSphere Mar 2021, one of the largest bacterial phyla, are ubiquitous in many of Earth's ecosystems and often act as defensive symbionts with animal hosts. Members of the phylum have...
, one of the largest bacterial phyla, are ubiquitous in many of Earth's ecosystems and often act as defensive symbionts with animal hosts. Members of the phylum have repeatedly been isolated from basidiomycete-cultivating fungus-farming termites that maintain a monoculture fungus crop on macerated dead plant substrate. The proclivity for antimicrobial and enzyme production of make them likely contributors to plant decomposition and defense in the symbiosis. To test this, we analyzed the prophylactic (biosynthetic gene cluster [BGC]) and metabolic (carbohydrate-active enzyme [CAZy]) potential in 16 (10 existing and six new genomes) termite-associated and compared these to the soil-dwelling close relatives. Using antiSMASH, we identified 435 BGCs, of which 329 (65 unique) were similar to known compound gene clusters, while 106 were putatively novel, suggesting ample prospects for novel compound discovery. BGCs were identified among all major compound categories, including 26 encoding the production of known antimicrobial compounds, which ranged in activity (antibacterial being most prevalent) and modes of action that might suggest broad defensive potential. Peptide pattern recognition analysis revealed 823 (43 unique) CAZymes coding for enzymes that target key plant and fungal cell wall components (predominantly chitin, cellulose, and hemicellulose), confirming a substantial degradative potential of these bacteria. Comparison of termite-associated and soil-dwelling bacteria indicated no significant difference in either BGC or CAZy potential, suggesting that the farming termite hosts may have coopted these soil-dwelling bacteria due to their metabolic potential but that they have not been subject to genome change associated with symbiosis. have repeatedly been isolated in fungus-farming termites, and our genome analyses provide insights into the potential roles they may serve in defense and for plant biomass breakdown. These insights, combined with their relatively higher abundances in fungus combs than in termite gut, suggest that they are more likely to play roles in fungus combs than in termite guts. Up to 25% of the BGCs we identify have no similarity to known clusters, indicating a large potential for novel chemistry to be discovered. Similarities in metabolic potential of soil-dwelling and termite-associated bacteria suggest that they have environmental origins, but their consistent presence with the termite system suggests their importance for the symbiosis.
Topics: Actinobacteria; Animals; Fungi; Genome, Bacterial; Genomics; Isoptera; Multigene Family; Phylogeny; Symbiosis
PubMed: 33658277
DOI: 10.1128/mSphere.01233-20 -
Microorganisms Nov 2020The diversity of cultural in two types of Algerian Sahara environments, including saline environments and date palms rhizosphere, was investigated. In this study, a...
The diversity of cultural in two types of Algerian Sahara environments, including saline environments and date palms rhizosphere, was investigated. In this study, a total of 40 strains of actinomycetes was isolated from different soil samples, using a rehydration and centrifugation method. Molecular identification, based on 16S rRNA gene sequence analysis, revealed that these isolates were affiliated to six clusters corresponding to eight genera, including , and . A taxonomic analysis, based on the morphological, physiological, biochemical, and molecular investigation, of selected strains, which belong to the rare , was undertaken. Four strains (CG3, A111, A93, and A79) were found to form distinct phyletic lines and represent new actinobacterial taxa. An assessment of antimicrobial proprieties of the 40 obtained actinomycetes strains, showed moderate to strong antimicrobial activities against fungi and bacteria. This study demonstrated the richness of Algerian Sahara with rare , which can provide novel bioactive metabolites, to solving some of the most challenging problems of the day, such as multi-drug resistance.
PubMed: 33255541
DOI: 10.3390/microorganisms8121853 -
BMC Infectious Diseases Nov 2020Mycetoma is a chronic granulomatous subcutaneous infection caused by anaerobic pseudofilamentous bacteria or fungi. It is commonly prevalent in tropical and subtropical...
BACKGROUND
Mycetoma is a chronic granulomatous subcutaneous infection caused by anaerobic pseudofilamentous bacteria or fungi. It is commonly prevalent in tropical and subtropical countries. Men are more susceptible to the disease due to greater participation in agricultural works. Mycetoma commonly involves lower extremities, wherein untreated cases lead to aggressive therapeutic choices, such as amputation of the affected body organs and consequently lifelong disability.
CASE PRESENTATION
In this report, we present the rare case of a 58-year-old man, originally from Algeria with a left foot chronic tumefaction of 5 years. In the initial clinical examination, mycetoma was diagnosed based on tumefaction and the presence of multiple sinuses with the emission of white grains. The latter was observed via direct examination. The histopathological analysis demonstrated an actinomycetoma caused by bacteria, as the etiological agent. Imaging showed a bone involvement with osteolysis at the levels of 2nd to 4th metatarsal diaphysis. The mycological and bacterial cultures were both negative. For an accurate diagnosis, the obtained grains were subjected to molecular analysis, targeting the 16S-rDNA gene. Molecular identification yielded Actinomadura madurae as the causal agent, and 800/160 mg of trimethoprim/sulfamethoxazole was prescribed twice a day for 1 year, as a treatment.
CONCLUSION
Considering low information about this disease, especially in non-endemic areas, it is of high importance to enhance the knowledge and awareness of clinicians and healthcare providers, in particular in the countries with immigration issues.
Topics: Actinobacteria; Actinomadura; Algeria; Anti-Bacterial Agents; DNA, Ribosomal; Emigrants and Immigrants; Foot; Humans; Male; Middle Aged; Mycetoma; Paris; Treatment Outcome; Trimethoprim, Sulfamethoxazole Drug Combination
PubMed: 33176717
DOI: 10.1186/s12879-020-05552-z -
Microorganisms Oct 2020Natural compounds have had increasing applications in the biotechnological sector, with a large fraction of these substances being channeled to the pharmaceutical...
Natural compounds have had increasing applications in the biotechnological sector, with a large fraction of these substances being channeled to the pharmaceutical industry due to their important pharmacological properties. The discovery of new bioactive molecules with novel mechanisms of action constitutes a promising solution for the design of alternative therapeutic solutions. Actinobacteria are a large group of morphologically and physiologically diverse bacteria well known for their production of biotechnologically relevant compounds. The Portuguese coast is scantly explored in terms of Actinobacteria diversity and respective bioactive potential, offering a good opportunity to find new Actinobacteria taxa and bioactive natural products. In this study, we investigated the Actinobacteria diversity associated with a sediment sample collected from the intertidal zone of a beach in northern Portugal, through a cultivation-dependent approach, and screened its antimicrobial and cytotoxic potential. A total of 52 Actinobacteria strains were recovered from the marine sediment, with the largest fraction of the isolates belonging to the genus . Bioactivity screening assays identified crude extracts of six strains active against , exhibiting minimum inhibition concentration (MIC) values in the range of 3.90-125 μg mL. Twenty-five Actinobacteria crude extracts (obtained from strains of the genera , and ) exhibited significant effects on the viability of at least one tested cancer cell line (breast ductal carcinoma T-47D and liver hepatocellular carcinoma HepG2). The Actinobacteria extracts demonstrating activity in the antimicrobial and/or cytotoxic assays were subjected to metabolomic analysis (Mass spectrometry (MS)-based dereplication and molecular networking analyses), indicating the presence of four clusters that may represent new natural products. The results obtained demonstrate the importance of bioprospecting underexplored environments, like the Portuguese coast, for enhancing the discovery of new natural products, and call attention to the relevance of preserving the natural genetic diversity of coastal environments.
PubMed: 33143202
DOI: 10.3390/microorganisms8111691 -
Journal of Family Medicine and Primary... Jul 2020Mycetoma is disorder of subcutaneous tissue, skin, and bones, mainly the feet. Etiologically divided in Eumycetoma and actinomycetoma, since the treatment of both is...
Mycetoma is disorder of subcutaneous tissue, skin, and bones, mainly the feet. Etiologically divided in Eumycetoma and actinomycetoma, since the treatment of both is different, the diagnosis is mandatory. This is the case of 35-year-old lady with swelling in left foot with multiple discharging sinuses for 5 years that was none responding to antifungal treatment. Change of treatment after the culture confirmation of species improves patient condition drastically.
PubMed: 33102362
DOI: 10.4103/jfmpc.jfmpc_481_20 -
AMB Express Oct 2020Fusarium wilt (FW) caused by Fusarium oxysporum f. sp. niveum (FON) is a soil-borne disease that seriously limits watermelon production. In the present study,...
Fusarium wilt (FW) caused by Fusarium oxysporum f. sp. niveum (FON) is a soil-borne disease that seriously limits watermelon production. In the present study, Trichoderma asperellum (T. asperellum) M45a was shown to be an effective biocontrol agent against FW. In a pot experiment, the application of 10 cfu/g of T. asperellum M45a granules had an improved control effect on FW during the blooming period (up to 67.44%) in soils subjected to five years of continuous cropping with watermelon, while the average length of watermelon vines was also significantly improved (P < 0.05). Additionally, the acid phosphatase (ACP), cellulase (CL), catalase (CAT), and sucrase (SC) activities in the M45a-inoculation group were significantly higher than those in the control (CK) group, and transformation of the soil nutrients (total N, NO3-N, and available P) was significantly increased. Moreover, T. asperellum M45a inoculation reduced fungal diversity, increased bacterial diversity and especially enhanced the relative abundance of plant growth-promoting rhizobacteria (PGPR), such as Trichoderma, Sphingomonas, Pseudomonas, Actinomadura, and Rhodanobacter. Through functional prediction, the relative abundance of ectomycorrhiza, endophytes, animal pathotrophs, and saprotrophs in the fungal community was determined to be significantly lower than that observed in the M45a-treated soil. Correlation analysis revealed that Sphingomonas, Pseudomonas, and Trichoderma had the most differences in terms of microorganism abundance, and these differences were positively correlated with ACP, CL, CAT, and SC. These findings provide guidance for the use of fungicides to achieve microecological control of FW in continuously cropped watermelon plots.
PubMed: 33095335
DOI: 10.1186/s13568-020-01126-z