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Molecules (Basel, Switzerland) Nov 2022Large scale cultivation and chemical investigation of an extract obtained from sp. resulted in the identification of six previously undescribed spirotetronates...
Large scale cultivation and chemical investigation of an extract obtained from sp. resulted in the identification of six previously undescribed spirotetronates (pyrrolosporin B and decatromicins C-G; -), along with six known congeners, namely decatromicins A-B (-), BE-45722B-D (-), and pyrrolosporin A (). The chemical structures of compounds - were characterized via comparison with previously reported data and analysis of 1D/2D NMR and MS data. The structures of all new compounds were highly related to the spirotetronate type compounds, decatromicin and pyrrolosporin, with variations in the substituents on the pyrrole and aglycone moieties. All compounds were evaluated for antibacterial activity against the Gram-negative bacteria, and Gram-positive bacteria, and were investigated for their cytotoxicity against the human cancer cell line A549. Of these, decatromicin B (), BE-45722B (), and pyrrolosporin B () exhibited potent antibacterial activities against both Gram-positive (MIC between 1-3 μM) and Gram-negative bacteria (MIC values ranging from 12-36 μM) with weak or no cytotoxic activity against A549 cells.
Topics: Humans; Polyketides; Actinomadura; Anti-Bacterial Agents; Gram-Negative Bacteria; Gram-Positive Bacteria; Microbial Sensitivity Tests
PubMed: 36500287
DOI: 10.3390/molecules27238196 -
Applied and Environmental Microbiology May 2022Nonheme iron- and α-ketoglutarate (αKG)-dependent halogenases (NHFeHals), which catalyze the regio- and stereoselective halogenation of the unactivated C()-H bonds,...
Nonheme iron- and α-ketoglutarate (αKG)-dependent halogenases (NHFeHals), which catalyze the regio- and stereoselective halogenation of the unactivated C()-H bonds, exhibit tremendous potential in the challenging asymmetric halogenation. AdeV from Actinomadura sp. ATCC 39365 is the first identified carrier protein-free NHFeHal that catalyzes the chlorination of nucleotide 2'-deoxyadenosine-5'-monophosphate (2'-dAMP) to afford 2'-chloro-2'-deoxyadenosine-5'-monophosphate. Here, we determined the complex crystal structures of AdeV/Fe/Cl and AdeV/Fe/Cl/αKG at resolutions of 1.76 and 1.74 Å, respectively. AdeV possesses a typical β-sandwich topology with H194, H252, αKG, chloride, and one water molecule coordinating Fe in the active site. Molecular docking, mutagenesis, and biochemical analyses reveal that the hydrophobic interactions and hydrogen bond network between the substrate-binding pocket and the adenine, deoxyribose, and phosphate moieties of 2'-dAMP are essential for substrate recognition. Residues H111, R177, and H192 might play important roles in the second-sphere interactions that control reaction partitioning. This study provides valuable insights into the catalytic selectivity of AdeV and will facilitate the rational engineering of AdeV and other NHFeHals for synthesis of halogenated nucleotides. Halogenated nucleotides are a group of important antibiotics and are clinically used as antiviral and anticancer drugs. AdeV is the first carrier protein-independent nonheme iron- and α-ketoglutarate (αKG)-dependent halogenase (NHFeHal) that can selectively halogenate nucleotides and exhibits restricted substrate specificity toward several 2'-dAMP analogues. Here, we determined the complex crystal structures of AdeV/Fe/Cl and AdeV/Fe/Cl/αKG. Molecular docking, mutagenesis, and biochemical analyses provide important insights into the catalytic selectivity of AdeV. This study will facilitate the rational engineering of AdeV and other carrier protein-independent NHFeHals for synthesis of halogenated nucleotides.
Topics: Carrier Proteins; Ferrous Compounds; Halogenation; Halogens; Iron; Ketoglutaric Acids; Molecular Docking Simulation; Nucleotides
PubMed: 35435717
DOI: 10.1128/aem.02497-21 -
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 -
Indian Journal of Dermatology,... 2022Background Mycetoma is widespread in Yemen; however, there are only a few documented reports on the entity from this geographical area. Methods A prospective study of...
Background Mycetoma is widespread in Yemen; however, there are only a few documented reports on the entity from this geographical area. Methods A prospective study of 184 cases of mycetoma (male 145 and female 39) from different regions of north-western Yemen was conducted between July 2000 and May 2014. Clinical profile was recorded in a standardized protocol. The diagnosis was based on clinical features, X-ray studies, examination of grains, and histopathology. Results Eumycetoma was diagnosed in 129, caused by Madurella mycetomatis in 124, Leptosphaeria senegalensis in one and pale grain fungus in four, whereas actinomycetoma occurred in 55, caused by Streptomyces somaliensis in 29, Actinomadura madurai in nine, Actinomadura pelletieri in one, and Nocardia in sixteen. Eumycetoma cases were treated with prolonged course of antifungal drugs, mostly ketoconazole, with itraconazole being used in four patients, along with excision or debulking. Results were better when antifungal drugs were given two to three months before surgery and in those who received itraconazole. Actinomycetoma cases were initially treated with co-trimoxazole monotherapy; later streptomycin was added in 30 cases. Six patients who did not show adequate improvement and two others from the start were treated with modified Welsh regimen and with good results. Limitations Identification of different causative agents was done by histopathology and could not be reconfirmed by culture. Conclusion Mycetoma is widespread in north-western Yemen with a higher incidence of eumycetoma and a majority of the cases were caused by Madurella mycetomatis. Modified Welsh regimen in actinomycetoma and itraconazole with excision in eumycetoma showed the best results.
Topics: Antifungal Agents; Female; Humans; India; Itraconazole; Madurella; Male; Mycetoma; Prospective Studies; Yemen
PubMed: 35389029
DOI: 10.25259/IJDVL_500_2021 -
Brazilian Journal of Microbiology :... 2018To mitigate the deleterious effects of abiotic stress, the use of plant growth-promoting bacteria along with diazotrophic bacteria has been increasing. The objectives of...
To mitigate the deleterious effects of abiotic stress, the use of plant growth-promoting bacteria along with diazotrophic bacteria has been increasing. The objectives of this study were to investigate the key enzymes related to nitrogen and carbon metabolism in the biological nitrogen fixation process and to elucidate the activities of these enzymes by the synergistic interaction between Bradyrhizobium and plant growth-promoting bacteria in the absence and presence of salt stress. Cowpea plants were cultivated under axenic conditions, inoculated with Bradyrhizobium and co-inoculated with Bradyrhizobium sp. and Actinomadura sp., Bradyrhizobium sp. and Bacillus sp., Bradyrhizobium sp. and Paenibacillus graminis, and Bradyrhizobium sp. and Streptomycessp.; the plants were also maintained in the absence (control) and presence of salt stress (50mmolL NaCl). Salinity reduced the amino acids, free ammonia, ureides, proteins and total nitrogen content in nodules and increased the levels of sucrose and soluble sugars. The co-inoculations responded differently to the activity of glutamine synthetase enzymes under salt stress, as well as glutamate synthase, glutamate dehydrogenase aminating, and acid invertase in the control and salt stress. Considering the development conditions of this experiment, co-inoculation with Bradyrhizobium sp. and Bacillus sp. in cowpea provided better symbiotic performance, mitigating the deleterious effects of salt stress.
Topics: Actinobacteria; Agricultural Inoculants; Amino Acids; Bradyrhizobium; Carbon; Nitrogen; Nitrogen Fixation; Plant Roots; Salt Stress; Sodium Chloride; Soil Microbiology; Vigna
PubMed: 29703526
DOI: 10.1016/j.bjm.2018.01.007 -
Mycopathologia Dec 2018Mycetoma is a chronic inflammatory process caused either by fungi (eumycetoma) or bacteria (actinomycetoma). In this retrospective study, we report epidemiologic and...
BACKGROUND
Mycetoma is a chronic inflammatory process caused either by fungi (eumycetoma) or bacteria (actinomycetoma). In this retrospective study, we report epidemiologic and histopathological data of mycetoma observed in the Lome Hospital, Togo in a 25-year period (1992-2016).
METHODOLOGY
This is a retrospective study, over a period of 25 years, to analyze epidemiological and etiological findings of mycetomas seen in the single laboratory of pathological anatomy of the Lomé, Togo.
RESULTS
A total of 61 cases were retrieved from which only 33 cases were included which where clinically and microbiologically confirmed. The mean age of the patients was 29.7 ± 1.34 and a sex ratio (M/F) of 1.5. The majority of patients were farmers (n = 23 cases; 69.7%). Diagnosed etiologic agents were fungal in 24 cases (72.7%) and actinomycotic cases in 9 cases (27.3%). The fungal mycetomas consisted of Madurella mycetomatis (black grains) and Falcifomispora senegaliensis (black grains). The actinomycotic agents were represented by Actinomadura madurae (white grains), Actinomadurae pelletieri (red grains) and Nocardia sp. (yellow grains).
CONCLUSION
This report represents a single-center study which provides epidemiologic and histopathological data of mycetoma cases in Togo.
Topics: Actinobacteria; Adolescent; Adult; Aged; Child; Cross-Sectional Studies; Female; Fungi; Histocytochemistry; Hospitals; Humans; Male; Middle Aged; Mycetoma; Retrospective Studies; Togo; Young Adult
PubMed: 29557534
DOI: 10.1007/s11046-018-0260-y -
PLoS Neglected Tropical Diseases Nov 2013Mycetoma is a chronic infectious disease of the subcutaneous tissue with a high morbidity. This disease has been reported from countries between 30°N and 15°S since... (Meta-Analysis)
Meta-Analysis Review
Mycetoma is a chronic infectious disease of the subcutaneous tissue with a high morbidity. This disease has been reported from countries between 30°N and 15°S since 1840 but the exact burden of disease is not known. It is currently unknown what the incidence, prevalence and the number of reported cases per year per country is. In order to estimate what the global burden of mycetoma is, a meta-analysis was performed. In total 50 studies were included, which resulted in a total of 8763 mycetoma cases. Most cases were found in men between 11 and 40 years of age. The foot was most commonly affected. Most cases were reported from Mexico, Sudan and India. Madurella mycetomatis was the most prevalent causative agent world-wide, followed by Actinomadura madurae, Streptomyces somaliensis, Actinomadura pelletieri, Nocardia brasiliensis and Nocardia asteroides. Although this study represents a first indication of the global burden on mycetoma, the actual burden is probably much higher. In this study only cases reported to literature could be used and most of these cases were found by searching archives from a single hospital in a single city of that country. By erecting (inter)national surveillance programs a more accurate estimation of the global burden on mycetoma can be obtained.
Topics: Adolescent; Adult; Child; Global Health; Humans; Mycetoma; Young Adult
PubMed: 24244780
DOI: 10.1371/journal.pntd.0002550 -
Saudi Journal of Biological Sciences Jun 2022Fungi colonizing fruits in the field and post-harvest constitute a major threat to the global food sector. This study focuses on the biocontrol of (aflatoxin-producing...
Fungi colonizing fruits in the field and post-harvest constitute a major threat to the global food sector. This study focuses on the biocontrol of (aflatoxin-producing mold considered carcinogenic by IARC) and f. sp. albedinis (FOA) (phytopathogenic agent, causal of El Bayoud in the Algerian and Moroccan Sahara). These molds have a significant economic impact and pose a serious human health problem. The aim of this work is to study the antifungal activity of two rare actinomycetes strains; sp. COL22 and sp. COL08 strains against toxinogenic and . f. sp. albedinis. The strains are isolated from rhizosphere on different media: ISP2, GLM, TSA, Starch-casein-agar and WYE and with different treatments of the samples (physical, chemical treatment and enrichment). The antifungal tests against the pathogenic microorganisms were performed on ISP2, GLM and TSA medium by means of the agar cylinders method. The kinetics of antibiotic production were performed on ISP medium over 16 days. The characterization of the antimicrobial compounds by LC-ESI/MS-MS showed that the bacterial extracts contain Antibiotic SF 2738C, Tetrodecamycin and Aplysillamide B. The phenotypic and molecular studies showed that sp. COL22 is closely related to the strain type and that sp. COL08 is closely related to the strain type. The two strains are rare and showed an interesting activity against toxinogenic and f. sp. albedinis.
PubMed: 35574281
DOI: 10.1016/j.sjbs.2022.103288 -
Antioxidant response of cowpea co-inoculated with plant growth-promoting bacteria under salt stress.Brazilian Journal of Microbiology :... 2018Soil salinity is an important abiotic stress worldwide, and salt-induced oxidative stress can have detrimental effects on the biological nitrogen fixation. We...
Soil salinity is an important abiotic stress worldwide, and salt-induced oxidative stress can have detrimental effects on the biological nitrogen fixation. We hypothesized that co-inoculation of cowpea plants with Bradyrhizobium and plant growth-promoting bacteria would minimize the deleterious effects of salt stress via the induction of enzymatic and non-enzymatic antioxidative protection. To test our hypothesis, cowpea seeds were inoculated with Bradyrhizobium or co-inoculated with Bradyrhizobium and plant growth-promoting bacteria and then submitted to salt stress. Afterward, the cowpea nodules were collected, and the levels of hydrogen peroxide; lipid peroxidation; total, reduced and oxidized forms of ascorbate and glutathione; and superoxide dismutase, catalase and phenol peroxidase activities were evaluated. The sodium and potassium ion concentrations were measured in shoot samples. Cowpea plants did not present significant differences in sodium and potassium levels when grown under non-saline conditions, but sodium content was strongly increased under salt stress conditions. Under non-saline and salt stress conditions, plants co-inoculated with Bradyrhizobium and Actinomadura or co-inoculated with Bradyrhizobium and Paenibacillus graminis showed lower hydrogen peroxide content in their nodules, whereas lipid peroxidation was increased by 31% in plants that were subjected to salt stress. Furthermore, cowpea nodules co-inoculated with Bradyrhizobium and plant growth-promoting bacteria and exposed to salt stress displayed significant alterations in the total, reduced and oxidized forms of ascorbate and glutathione. Inoculation with Bradyrhizobium and plant growth-promoting bacteria induced increased superoxide dismutase, catalase and phenol peroxidase activities in the nodules of cowpea plants exposed to salt stress. The catalase activity in plants co-inoculated with Bradyrhizobium and Streptomyces was 55% greater than in plants inoculated with Bradyrhizobium alone, and this value was remarkably greater than that in the other treatments. These results reinforce the beneficial effects of plant growth-promoting bacteria on the antioxidant system that detoxifies reactive oxygen species. We concluded that the combination of Bradyrhizobium and plant growth-promoting bacteria induces positive responses for coping with salt-induced oxidative stress in cowpea nodules, mainly in plants co-inoculated with Bradyrhizobium and P. graminis or co-inoculated with Bradyrhizobium and Bacillus.
Topics: Agricultural Inoculants; Antioxidants; Bradyrhizobium; Catalase; Glutathione; Lipid Peroxidation; Oxidative Stress; Peroxidase; Plant Proteins; Salinity; Sodium Chloride; Stress, Physiological; Superoxide Dismutase; Vigna
PubMed: 29482998
DOI: 10.1016/j.bjm.2017.12.003 -
Applied Microbiology Jul 1969Thirteen red strains of Actinomadura (Nocardia) pelletieri and three of A. madurae were shown to produce prodigiosin-like pigments. Both of the two major pigments which...
Thirteen red strains of Actinomadura (Nocardia) pelletieri and three of A. madurae were shown to produce prodigiosin-like pigments. Both of the two major pigments which were observed on thin-layer chromatograms had R(F) values significantly greater than prodigiosin. The main pigment from A. madurae 953 was shown by mass and nuclear magnetic resonance spectroscopies to be nonylprodigiosin. The major pigment from A. pellitieri had a C(11)H(22) side chain in a ring form, but it was distinctly different from metacycloprodigiosin. "Prodiginine" was proposed as a name for the invariant aromatic portion of the prodigiosin structure.
Topics: Anti-Bacterial Agents; Chromatography; Chromatography, Thin Layer; Magnetic Resonance Spectroscopy; Nocardia; Pigments, Biological; Prodigiosin; Pyrroles; Spectrum Analysis
PubMed: 5803627
DOI: 10.1128/am.18.1.1-3.1969