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Scientific Reports Jul 2021Streptomyces smyrnaeus UKAQ_23, isolated from the mangrove-sediment, collected from Jubail,Saudi Arabia, exhibited substantial antimicrobial activity against...
Isolation, characterization, anti-MRSA evaluation, and in-silico multi-target anti-microbial validations of actinomycin X and actinomycin D produced by novel Streptomyces smyrnaeus UKAQ_23.
Streptomyces smyrnaeus UKAQ_23, isolated from the mangrove-sediment, collected from Jubail,Saudi Arabia, exhibited substantial antimicrobial activity against methicillin-resistant Staphylococcus aureus (MRSA), including non-MRSA Gram-positive test bacteria. The novel isolate, under laboratory-scale conditions, produced the highest yield (561.3 ± 0.3 mg/kg fermented agar) of antimicrobial compounds in modified ISP-4 agar at pH 6.5, temperature 35 °C, inoculum 5% v/w, agar 1.5% w/v, and an incubation period of 7 days. The two major compounds, K and K, were isolated from fermented medium and identified as Actinomycin X and Actinomycin D, respectively, based on their structural analysis. The antimicrobial screening showed that Actinomycin X had the highest antimicrobial activity compared to Actinomycin D, and the actinomycins-mixture (X:D, 1:1, w/w) against MRSA and non-MRSA Gram-positive test bacteria, at 5 µg/disc concentrations. The MIC of Actinomycin X ranged from 1.56-12.5 µg/ml for non-MRSA and 3.125-12.5 µg/ml for MRSA test bacteria. An in-silico molecular docking demonstrated isoleucyl tRNA synthetase as the most-favored antimicrobial protein target for both actinomycins, X and D, while the penicillin-binding protein-1a, was the least-favorable target-protein. In conclusion, Streptomyces smyrnaeus UKAQ_23 emerged as a promising source of Actinomycin X with the potential to be scaled up for industrial production, which could benefit the pharmaceutical industry.
Topics: Anti-Bacterial Agents; Computer Simulation; Culture Media; Dactinomycin; Drug Evaluation, Preclinical; Fermentation; Magnetic Resonance Spectroscopy; Mass Spectrometry; Methicillin-Resistant Staphylococcus aureus; Molecular Docking Simulation; Molecular Structure; Phylogeny; Streptomyces
PubMed: 34267232
DOI: 10.1038/s41598-021-93285-7 -
Proceedings of the National Academy of... Nov 1970We have investigated the nature of the RNA that moves from cytoplasm to nucleus against a concentration gradient in Amoeba proteus. We find that: In the presence of...
We have investigated the nature of the RNA that moves from cytoplasm to nucleus against a concentration gradient in Amoeba proteus. We find that: In the presence of actinomycin D an unlabeled nucleus grafted into a [(3)H]RNA cytoplasm acquires RNAs with sedimentation constants 30 S, 19 S, and 4-6S that are not related to the general population of cytoplasmic ribosomal and transfer RNAs. RNAs of sedimentation constants 39 S and 16 S may also enter the nucleus from the cytoplasm, but not in the presence of actinomycin D. Nuclei were transplanted from [(3)H]RNA cells through several unlabeled cytoplasms to dilute out migrating [(3)H]RNA. This resulted in the 4-6 S [(3)H]RNA being retained as the predominant labeled material of the nucleus and establishes that a substantial portion of 4-6S nuclear RNA does not leave the interphase nucleus. We conclude that nuclear RNAs may be classified in a new way: (1) RNA that is to become cytoplasmic RNA and presumably moves only from nucleus to cytoplasm; (2) RNA that migrates back and forth between nucleus and cytoplasm; and (3) RNA that does not leave the nucleus during interphase.
Topics: Amoeba; Animals; Cell Nucleus; Centrifugation, Density Gradient; Cytoplasm; Dactinomycin; Mitosis; RNA; Tritium
PubMed: 5274464
DOI: 10.1073/pnas.67.3.1367 -
BMC Microbiology Feb 2019The increased rate of resistance among two highly concerned pathogens i.e. methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus (VRE)...
Purification and characterization of actinomycins from Streptomyces strain M7 active against methicillin resistant Staphylococcus aureus and vancomycin resistant Enterococcus.
BACKGROUND
The increased rate of resistance among two highly concerned pathogens i.e. methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus (VRE) necessitates the discovery of novel anti-MRSA and anti-VRE compounds. In microbial drug discovery, Streptomyces are well known source of two-thirds of natural antibiotics used clinically. Hence, screening of new strains of streptomycetes is the key step to get novel bioactive compounds with antimicrobial activity against drug resistant bacteria.
RESULTS
In the present study, Streptomyces antibioticus strain M7, possessing potent antibacterial activity against different pathogenic bacteria, was isolated from rhizospheric soil of Stevia rebudiana. 16S rRNA sequence of M7 (1418 bp) showed 96.47-100% similarity with different Streptomyces spp. and the maximum similarity (100%) was observed with Streptomyces antibioticus NBRC 12838 (AB184184). Phylogenetic analysis using neighbor joining method further validated its similarity with Streptomyces antibioticus NBRC 12838 T (AB184184) as it formed clade with the latter and showed high boot strap value (99%). Antibacterial metabolites isolated from the fermentation broth were characterized using NMR, FT-IR and LC-MS as actinomycins V, X and D. The purified actinomycins exhibited potent antibacterial activities against test bacteria viz. B. subtilis, K. pneumoniae sub sp. pneumoniae, S. aureus, S. epidermidis, S. typhi, E. coli, MRSA and VRE. Among these actinomycins, actinomycin X was more effective as compared to actinomycins D and V. The minimum inhibitory concentration values of purified compounds against a set of test bacterial organisms viz. VRE, MRSA, E. coli (S1-LF), K. pneumoniae sub sp. pneumoniae and B. subtilis ranged between 1.95 and 31.25 μg/ml.
CONCLUSIONS
This study demonstrates that actinomycins V, X and D produced by S. antibioticus strain M7 hold the potential to be used against multidrug resistant bacteria, particularly VRE and MRSA.
Topics: Anti-Bacterial Agents; Dactinomycin; Drug Discovery; Drug Resistance, Multiple, Bacterial; Methicillin-Resistant Staphylococcus aureus; Microbial Sensitivity Tests; Phylogeny; RNA, Ribosomal, 16S; Rhizosphere; Soil Microbiology; Stevia; Streptomyces; Vancomycin-Resistant Enterococci
PubMed: 30782119
DOI: 10.1186/s12866-019-1405-y -
British Medical Journal Apr 1972
Topics: Dactinomycin; Glucagon; Humans; Injections, Intravenous; Osteitis Deformans; Plicamycin
PubMed: 4259415
DOI: 10.1136/bmj.2.5804.47-a -
Cellular Physiology and Biochemistry :... 2009We investigated the effect of resveratrol on proliferation and induction of apoptosis of INS-1E rat insulinoma cells by cell counting, crystal violet staining, flow...
We investigated the effect of resveratrol on proliferation and induction of apoptosis of INS-1E rat insulinoma cells by cell counting, crystal violet staining, flow cytometry and immunoblotting. Resveratrol treatment of INS-1E cells at concentrations > or =50 microM resulted in a dose-dependent inhibition of cell proliferation, accumulation of the cells in the S and G0/G1 phase and a significant increase of the percentage of apoptotic cells. This was paralleled by an increase of cell granularity, apoptotic volume decrease (AVD), exposure of phosphatidylserine at the outer leaflet of the plasma membrane, an increase of the 7-AAD signal and caspase activation. The AMP-kinase (AMPK) inhibitor compound C (10 microM) significantly inhibited cell proliferation and induced caspase activation within 48 hours but this effect was not modified by resveratrol suggesting that AMPK is not a major target involved in mediating the proapoptotic effect of resveratrol in INS-1E cells. Immunoblotting revealed a significant inhibition of Akt (PKB) phosphorylation by 100 muM resveratrol within 1 hour. Addition of insulin (10 microM) to the culture medium strongly enhanced basal Akt phosphorylation. This enhancement was significantly attenuated by 50 and 100 microM resveratrol. We conclude that the antiproliferative/proapoptotic effect of resveratrol on INS-1E cells is due to negative interference with Akt signaling and most likely disruption of auto/paracrine insulin signaling.
Topics: Animals; Apoptosis; Caspases; Cell Cycle; Cell Line, Tumor; Dactinomycin; Insulin; Insulin-Secreting Cells; Insulinoma; Pancreatic Neoplasms; Phosphatidylserines; Phosphorylation; Proto-Oncogene Proteins c-akt; Rats; Resveratrol; Signal Transduction; Stilbenes; Time Factors
PubMed: 19471092
DOI: 10.1159/000218171 -
Marine Drugs Dec 2021Actinomycins as clinical medicine have been extensively studied, while few investigations were conducted to discover the feasibility of actinomycins as antimicrobial...
Actinomycins as clinical medicine have been extensively studied, while few investigations were conducted to discover the feasibility of actinomycins as antimicrobial natural dye contributing to the medical value of the functional fabrics. This study was focused on the application of actinomycin X2 (Ac.X2), a peptide pigment cultured from marine-derived , in the dyeing and finishing of silk fabric. The dyeing potential of Ac.X2 with silk vs. cotton fabrics was assessed. As a result, the silk fabric exhibited greater uptake and color fastness with Ac.X2. Through Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and X-ray diffraction (XRD) analyses, some changes of chemical property for the dyed fabric and Ac.X2 were studied. The silk fabric dyed with Ac.X2 exhibited good UV protection ability. The antibacterial properties of dyed and finished silk were also evaluated, which exhibited over 90% antibacterial activity even after 20 washing cycles. In addition, the brine shrimp assay was conducted to evaluate the general toxicity of the tested fabric, and the results indicated that the dyed silk fabrics had a good biological safety property.
Topics: Animals; Anti-Bacterial Agents; Aquatic Organisms; Artemia; Coloring Agents; Dactinomycin; Microbial Sensitivity Tests; Microscopy, Electron, Scanning; Silk; Spectroscopy, Fourier Transform Infrared; Staphylococcus aureus; Streptomyces
PubMed: 35049871
DOI: 10.3390/md20010016 -
The Journal of Biological Chemistry May 1967
Topics: Blood Platelets; Blood Proteins; Carbon Isotopes; Chromatography, Paper; Dactinomycin; Humans; In Vitro Techniques; Leucine; Puromycin
PubMed: 6022853
DOI: No ID Found -
Proceedings of the National Academy of... Jan 1963
Topics: Chromosomes; Dactinomycin; Gene Expression; Research Design; Tissue Culture Techniques
PubMed: 14025352
DOI: 10.1073/pnas.49.1.53 -
Neuro-oncology Sep 2020
Topics: Dactinomycin; Glioblastoma; Humans; SOXB1 Transcription Factors
PubMed: 32678904
DOI: 10.1093/neuonc/noaa172 -
The American Journal of Pathology Apr 1999Human islet amyloid polypeptide (hIAPP) is co-secreted with insulin from pancreatic islet beta cells. This peptide spontaneously aggregates in the form of fibrils, and...
Human islet amyloid polypeptide (hIAPP) is co-secreted with insulin from pancreatic islet beta cells. This peptide spontaneously aggregates in the form of fibrils, and amyloid deposits are associated with dead or degenerating beta cells, a hallmark of noninsulin-dependent diabetes mellitus. We demonstrated that COS-1 cells transfected with vectors expressing hIAPP exhibited intracellular amyloid deposits that were associated with cell death (O'Brien, Butler, Kreutter, Kane, Eberhardt, Am J Pathol 1995, 147:609-616). To establish the mechanism of cell death, we transfected COS-1 cells with vectors expressing amyloidogenic hIAPP or nonamyloidogenic rat IAPP and mutant hIAPP constructs and assayed them for markers characteristic of apoptosis and necrosis by fluorescence-activated cell sorting analysis. Amyloidogenic hIAPP-transfected COS cells contained up to threefold more apoptotic cells present at 96 hours after transfection compared with the nonamyloidogenic vector controls. The hIAPP-induced apoptosis was negligible at 24 and 48 hours after transfection and was maximal at 96 hours which parallels the time course of amyloidogenesis. Immunohistochemical staining and confocal microscopy showed that hIAPP is localized with distinct clustering in the endoplasmic reticulum and Golgi apparatus with no discernable extracellular staining. These experiments provide direct evidence that intracellular hIAPP amyloid causes cell death by triggering apoptotic pathways.
Topics: Amyloid; Animals; Annexin A5; Apoptosis; COS Cells; Cell Death; Cell Survival; Dactinomycin; Flow Cytometry; Humans; Immunohistochemistry; In Situ Nick-End Labeling; Intracellular Fluid; Islet Amyloid Polypeptide; Microscopy, Confocal; Rats; Time Factors; Transfection
PubMed: 10233846
DOI: 10.1016/S0002-9440(10)65360-6