-
Natural Products and Bioprospecting Oct 2023Microbes well-adapted to the Arctic Ocean are promising for producing novel compounds, due to their fancy strategies for adaptation and being under-investigated. Two new...
Microbes well-adapted to the Arctic Ocean are promising for producing novel compounds, due to their fancy strategies for adaptation and being under-investigated. Two new phenazine alkaloids (1 and 2) and one new phenoxazine (3) were isolated from Nocardiopsis dassonvillei 502F, a strain originally isolated from Arctic deep-sea sediments. AntiSMASH analysis of the genome of Nocardiopsis dassonvillei 502F revealed the presence of 16 putative biosynthetic gene clusters (BGCs), including a phenazine BGC. Most of the isolated compounds were evaluated for their antibacterial, antiallergic, and cytotoxic activities. Among them, compounds 4 and 5 exhibited potent in vitro cytotoxic activities against osteosarcoma cell line 143B with IC values 0.16 and 20.0 μM, respectively. Besides, the results of antiallergic activities of compounds 6-8 exhibited inhibitory activities with IC values of 10.88 ± 3.05, 38.88 ± 3.29, and 2.44 ± 0.17 μg/mL, respectively (IC 91.6 μM for the positive control loratadine).
PubMed: 37848577
DOI: 10.1007/s13659-023-00408-w -
Saudi Journal of Biological Sciences Mar 2020The sediment marine samples were obtained from several places along the coastline of the Tuticorin shoreline, Tamil Nadu, India were separated for the presence of...
The sediment marine samples were obtained from several places along the coastline of the Tuticorin shoreline, Tamil Nadu, India were separated for the presence of bioactive compound producing actinobacteria. The actinobacterial strain was subjected to 16Sr RNA sequence cluster analysis and identified as DS013 NCBI accession number: KM098151. Bacterial mediated synthesis of nanoparticles gaining research attention owing its wide applications in nonmedical biotechnology. In the current study, a single step eco-friendly silver nanoparticles (AgNPs) were synthesized from novel actinobacteria DS013 has been attempted. The actinobacterial mediated silver nanoparticles were characterized by TEM, UV-Visible, XRD, FT-IR spectroscopy. The initial detection of AgNPs was identified using UV-Vis spectrum and confirmed by the appearance of absorbance peak at 408 nm. A Fourier transform infrared spectroscopy (FT-IR) result reveals the presence of protein component in the culture supernatant may act as protecting agents. The XRD pattern indicated that the typical peaks reveal the presence of nanoparticles. The TEM morphology confirms the formation of circular and non uniform distributions of AgNPs with the size range from 30 to 80 nm. The antibacterial activity of both isolated actinobacterial (IA) and silver nanoparticles mediated actinobacterial (SNA) of DS013 were done by well diffusion method against selected clinical isolates of bacteria, namely sp. sp. sp. sp. sp. and sp. When compared to isolated actinobacteria, the SNA shows the better antibacterial activity against clinical isolates.
PubMed: 32127778
DOI: 10.1016/j.sjbs.2020.01.003 -
Frontiers in Microbiology 2021Nanoparticles have recently emerged as a popular research topic. Because of their potential applications in therapeutic applications, biosynthesized silver nanoparticles...
Nanoparticles have recently emerged as a popular research topic. Because of their potential applications in therapeutic applications, biosynthesized silver nanoparticles (Bio-AgNPs) have gained much attention in recent years. Cell-free extracts (CFE) from a marine culture of actinobacteria and silver nitrate were used to reduce Ag ions and create Bio-AgNPs. KY772427, a new silver-tolerant actinomycete strain, was isolated from marine water and used to synthesize AgNPs. In order to characterize Bio-AgNPs, UV-Vis spectral analysis, Fourier transform infrared (FTIR), transmission electron microscopy (TEM), and dynamic light scattering spectroscopy (DLS) were all utilized. Using UV-Vis spectroscopy, a peak in the surface plasmon resonance (SPR) spectrum at 430 nm revealed the presence of Bio-AgNPs. The TEM revealed spherical AgNPs with a diameter of 29.28 nm. DLS determined that Bio-AgNPs have a diameter of 56.1 nm and a negative surface charge (-1.46 mV). The minimum inhibitory concentration (MIC) of Bio-AgNPs was determined against microbial strains. Using resazurin-based microtiter dilution, the synergistic effect of Bio-AgNPs with antimicrobials was investigated. had the lowest MIC of Bio-AgNPs (4 μg/ml). Surprisingly, the combination of antimicrobials and Bio-AgNPs had a significant synergistic effect on the tested strains. The insecticidal activity of Bio-AgNPs (200 μg/ml) against was found to be maximal after 36 h. Additionally, Bio-AgNPs demonstrated significant scavenging activity against 2,2'-diphenyl-1-picrylhydrazyl (DPPH) and hydroxyl (OH ) radicals, with values of 4.08 and 8.9 g/ml, respectively. studies using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay revealed a concentration-dependent decrease in cell viability when CaCo2 cells were exposed to Bio-AgNPs. With the decrease in cell viability, lactate dehydrogenase leakage (LDH) increased. The findings of this study open up a new avenue for the use of marine to produce Bio-AgNPs, which have significant antimicrobial, antioxidant, insecticidal, and anticancer potential.
PubMed: 35211096
DOI: 10.3389/fmicb.2021.705673 -
Scientific Reports May 2021Recent advancements in DNA-based approaches have led to the identification of uncommon and rare bacterial pathogens. In this study, by utilizing a DNA-based approach, a...
Recent advancements in DNA-based approaches have led to the identification of uncommon and rare bacterial pathogens. In this study, by utilizing a DNA-based approach, a total of 1043 clinical specimens were processed for the identification of actinobacteria targeting the 16S rRNA and gyrB genes. Drug susceptibility testing was also conducted using micro-broth dilution and PCR. Two isolates of Nocardia flavorosea and Rhodococcus erythropolis were reported for the first time in Iran. Also, Nocardiopsis dassonvillei, Streptomyces olivaceus, and Streptomyces griseus were reported for the first time in Asia. Infections caused by Nocardia caishijiensis and Prauserella muralis have also been reported in this study. The first Asian case of pulmonary infection caused by Nocardia ignorata and the first global case of brain abscess caused by Nocardia ninae and Nocardia neocaledoniensis have been reported in this study. Overall 30 isolates belonging to 6 genera (Nocardia, Streptomyces, Rodoccoccus, Nocardiopsis, Rothia, and Prauserella) were detected in 30 patients. All 30 isolates were susceptible to amikacin and linezolid. Three isolates including Nocardia otitidiscaviarum (n = 2) and Nocardia flavorosea (n = 1) were resistant to trimethoprim-sulfamethoxazole which were the first trimethoprim-sulfamethoxazole resistant clinical actinomycetes in Iran. Isolation of rare species of actinomycetes particularly Nocardia spp. requires urgent action before they spread clinically particularly among immunocompromised patients.
Topics: Actinomyces; Adult; Aged; Bacterial Infections; Case-Control Studies; Cross-Sectional Studies; DNA Gyrase; DNA, Bacterial; DNA, Ribosomal; Drug Resistance, Bacterial; Female; Humans; Immunocompromised Host; Iran; Male; Microbial Sensitivity Tests; Middle Aged; RNA, Ribosomal, 16S; Sequence Analysis, DNA; Trimethoprim, Sulfamethoxazole Drug Combination
PubMed: 34031507
DOI: 10.1038/s41598-021-90269-5 -
Asian Pacific Journal of Tropical... Jun 2012To isolate and identify Nocardia spp. from soil in different regions of Isfahan province in the center of Iran.
OBJECTIVE
To isolate and identify Nocardia spp. from soil in different regions of Isfahan province in the center of Iran.
METHODS
This study was conducted in 32 districts (16 cities and 16 villages) in Isfahan province during two years. A total of 800 soil samples from these regions were studied by using kanamycin. The isolated Nocardia species were examined by gram and acid-fast staining and were identified biochemically and morphologically. The frequency and distribution of Nocardia spp. were determined in relation to different factors such as soil pH and temperate climate.
RESULTS
From 153 (19.1%) Nocardia isolates identified, Nocardia asteroids (N. asteroids) complex (45.5%) and Nocardia brasiliensis (N. brasiliensis) (24.7%) were the most frequently isolated species, followed by Nocardia otitidiscaviarum (2.2%), Nocardiopsis dassonvillei, Actinomadura actinomadura (each 1.7%) and Nocardia transvalensis (1.1%) and also unknown spp. (23.0%). In this study, most species (54.4%) of Nocardia, especially N. asteroides complex were isolated from soils with pH: 7.01-8, whereas in pH: 8.01-9 more N. brasiliensis was isolated. The most Nocardia spp. was detected from regions with semi-nomadic and temperate climate (41.1%).
CONCLUSIONS
N. asteroids complex is more prevalent in Isfahan province and soil can be a potential source of nocardiosis infections. It is to be considering that climate and soil pH are involved in the frequency and diversity of aerobic Actinomycetes.
Topics: Bacteriological Techniques; Biodiversity; Hydrogen-Ion Concentration; Iran; Nocardia; Soil; Soil Microbiology; Temperature
PubMed: 23569953
DOI: 10.1016/S2221-1691(12)60079-3 -
Microbiology Resource Announcements Oct 2022The genome sequence (7,057,619 bp; GC content, 72.07%) of a tropical marine isolate, Nocardiopsis dassonvillei NCIM 5124, containing the biomedically and...
The genome sequence (7,057,619 bp; GC content, 72.07%) of a tropical marine isolate, Nocardiopsis dassonvillei NCIM 5124, containing the biomedically and biotechnologically important gene cluster is reported here.
PubMed: 36154194
DOI: 10.1128/mra.00435-22 -
Microorganisms Oct 2023The emergence of multidrug-resistant pathogens creates public health challenges, prompting a continuous search for effective novel antimicrobials. This study aimed to...
The emergence of multidrug-resistant pathogens creates public health challenges, prompting a continuous search for effective novel antimicrobials. This study aimed to isolate marine actinomycetes from South Africa, evaluate their in vitro antimicrobial activity against and Shiga toxin-producing , and characterize their mechanisms of action. Marine actinomycetes were isolated and identified by 16S rRNA sequencing. Gas chromatography-mass spectrometry (GC-MS) was used to identify the chemical constituents of bioactive actinomycetes' secondary metabolites. Antibacterial activity of the secondary metabolites was assessed by the broth microdilution method, and their mode of actions were predicted using computational docking. While five strains showed antibacterial activity during primary screening, only strain SOD(B)ST2SA2 exhibited activity during secondary screening for antibacterial activity. GC-MS identified five major bioactive compounds: 1-octadecene, diethyl phthalate, pentadecanoic acid, 6-octadecenoic acid, and trifluoroacetoxy hexadecane. SOD(B)ST2SA2's extract demonstrated minimum inhibitory concentration and minimum bactericidal concentration, ranging from 0.78-25 mg/mL and 3.13 to > 25 mg/mL, respectively. Diethyl phthalate displayed the lowest bacterial protein-binding energies (kcal/mol): -7.2, dihydrofolate reductase; -6.0, DNA gyrase B; and -5.8, D-alanine:D-alanine ligase. Thus, marine SOD(B)ST2SA2 is a potentially good source of antibacterial compounds that can be used to control STEC and .
PubMed: 37894198
DOI: 10.3390/microorganisms11102539 -
BioMed Research International 2017Next-generation DNA sequencing (NGS) has made it feasible to sequence large number of microbial genomes and advancements in computational biology have opened enormous...
Next-generation DNA sequencing (NGS) has made it feasible to sequence large number of microbial genomes and advancements in computational biology have opened enormous opportunities to mine genome sequence data for novel genes and enzymes or their sources. In the present communication in silico mining of microbial genomes has been carried out to find novel sources of nitrilases. The sequences selected were analyzed for homology and considered for designing motifs. The manually designed motifs based on amino acid sequences of nitrilases were used to screen 2000 microbial genomes (translated to proteomes). This resulted in identification of one hundred thirty-eight putative/hypothetical sequences which could potentially code for nitrilase activity. In vitro validation of nine predicted sources of nitrilases was done for nitrile/cyanide hydrolyzing activity. Out of nine predicted nitrilases, , , , and were specific for aliphatic nitriles, whereas nitrilases from , , , and possessed activity for aromatic nitriles. was specific towards potassium cyanide (KCN) which revealed the presence of nitrilase homolog, that is, cyanide dihydratase with no activity for either aliphatic, aromatic, or aryl nitriles. The present study reports the novel sources of nitrilases and cyanide dihydratase which were not reported hitherto by in silico or in vitro studies.
Topics: Aminohydrolases; Bacteria; Bacterial Proteins; Genome, Bacterial; High-Throughput Nucleotide Sequencing; Sequence Analysis, DNA
PubMed: 28497061
DOI: 10.1155/2017/7039245 -
Standards in Genomic Sciences Nov 2010Nocardiopsis dassonvillei (Brocq-Rousseau 1904) Meyer 1976 is the type species of the genus Nocardiopsis, which in turn is the type genus of the family Nocardiopsaceae....
Nocardiopsis dassonvillei (Brocq-Rousseau 1904) Meyer 1976 is the type species of the genus Nocardiopsis, which in turn is the type genus of the family Nocardiopsaceae. This species is of interest because of its ecological versatility. Members of N. dassonvillei have been isolated from a large variety of natural habitats such as soil and marine sediments, from different plant and animal materials as well as from human patients. Moreover, representatives of the genus Nocardiopsis participate actively in biopolymer degradation. This is the first complete genome sequence in the family Nocardiopsaceae. Here we describe the features of this organism, together with the complete genome sequence and annotation. The 6,543,312 bp long genome consist of a 5.77 Mbp chromosome and a 0.78 Mbp plasmid and with its 5,570 protein-coding and 77 RNA genes is a part of the Genomic Encyclopedia of Bacteria and Archaea project.
PubMed: 21304737
DOI: 10.4056/sigs.1363462 -
Microbiological Research Dec 2012A marine actinomycete, designated strain BM-17, was isolated from a sediment sample collected in the Arctic Ocean. The strain was identified as Nocardia dassonvillei...
A marine actinomycete, designated strain BM-17, was isolated from a sediment sample collected in the Arctic Ocean. The strain was identified as Nocardia dassonvillei based on morphological, cultural, physiological, biochemical characteristics, along with the cell wall analysis and 16S rDNA gene sequence analysis. A new secondary metabolite (1), N-(2-hydroxyphenyl)-2-phenazinamine (NHP), and six known antibiotics (2-7) have been isolated from the saline culture broth of the stain by sequentially purification over macroporous resin D101, silica gel, Sephadex LH-20 column chromatography and preparative HPLC after the stain was incubated in soy bean media at 28°C for 7 days. The chemical structures of the compounds were elucidated on the basis of spectroscopic analysis, including two-dimensional (2D) NMR and HR-ESI-MS data. The new compound showed significant antifungal activity against Candida albicans, with a MIC of 64 μg/ml and high cancer cell cytotoxicity against HepG2, A549, HCT-116 and COC1 cells.
Topics: Actinobacteria; Anti-Bacterial Agents; Antifungal Agents; Antineoplastic Agents; Arctic Regions; Biological Products; Candida albicans; Marine Biology; Nocardia; Oceans and Seas; Phenazines
PubMed: 22494896
DOI: 10.1016/j.micres.2012.02.008