Biogenic selenium nanoparticles and selenium/chitosan-Nanoconjugate biosynthesized by Streptomyces parvulus MAR4 with antimicrobial and anticancer potential.

BACKGROUND: As antibiotics and chemotherapeutics are no longer as efficient as they once were, multidrug resistant (MDR) pathogens and cancer are presently considered as two of the most dangerous threats to human life. In this study, Selenium nanoparticles (SeNPs) biosynthesized by Streptomyces parvulus MAR4, nano-chitosan (NCh), and their nanoconjugate (Se/Ch-nanoconjugate) were suggested to be efficacious antimicrobial and anticancer agents. RESULTS: SeNPs biosynthesized by Streptomyces parvulus MAR4 and NCh were successfully achieved and conjugated. The biosynthesized SeNPs were spherical with a mean diameter of 94.2 nm and high stability. Yet, Se/Ch-nanoconjugate was semispherical with a 74.9 nm mean diameter and much higher stability. The SeNPs, NCh, and Se/Ch-nanoconjugate showed significant antimicrobial activity against various microbial pathogens with strong inhibitory effect on their tested metabolic key enzymes [phosphoglucose isomerase (PGI), pyruvate dehydrogenase (PDH), glucose-6-phosphate dehydrogenase (G6PDH) and nitrate reductase (NR)]; Se/Ch-nanoconjugate was the most powerful agent. Furthermore, SeNPs revealed strong cytotoxicity against HepG2 (IC50 = 13.04 µg/ml) and moderate toxicity against Caki-1 (HTB-46) tumor cell lines (IC50 = 21.35 µg/ml) but low cytotoxicity against WI-38 normal cell line (IC50 = 85.69 µg/ml). Nevertheless, Se/Ch-nanoconjugate displayed substantial cytotoxicity against HepG2 and Caki-1 (HTB-46) with IC50 values of 11.82 and 7.83 µg/ml, respectively. Consequently, Se/Ch-nanoconjugate may be more easily absorbed by both tumor cell lines. However, it exhibited very low cytotoxicity on WI-38 with IC50 of 153.3 µg/ml. Therefore, Se/Ch-nanoconjugate presented the most anticancer activity. CONCLUSION: The biosynthesized SeNPs and Se/Ch-nanoconjugate are convincingly recommended to be used in biomedical applications as versatile and potent antimicrobial and anticancer agents ensuring notable levels of biosafety, environmental compatibility, and efficacy.

Antibacterial and biofilm disruptive nonribosomal lipopeptides from Streptomyces parvulus against multidrug-resistant bacterial infections.

BACKGROUND: In recent years, new drugs for the treatment of various diseases, thereby the emergence of antimicrobial resistance tremendously increased because of the increased consumption rate of various drugs. However, the irrational use of antibiotics increases the microbial resistance along with that the frequency of mortality associated with infections is higher. Broad-spectrum antibiotics were effectively against various bacteria and the unrestricted application of antibiotics lead to the emergence of drug resistance. The present study was aimed to detect the antibacterial properties of lipopeptide novel drug producing Streptomyces parvulus. METHODS: A lipopeptide-producing S. parvulus was isolated from the soil sample. The inhibitory effect of lipopeptide was detected against Gram-positive and Gram-negative bacteria. Bactericidal activity and minimum inhibitory concentration (MIC) were assayed. The IC50 value was analysed against ovarian and human melanoma cell lines. The experimental mouse model was infected withKlebsiella pneumoniae and treated with lipopeptide and bactericidal activity was determined. RESULTS: The results indicated that the antibacterial activity of lipopeptide ranges from 13 ± 1 mm to 32 ± 2 mm against Gram-positive and Gram-negative strains. The lowest MIC value was noted as 1.5 ± 0.1 µg/mL against K. pneumoniae and the highest against E. aerogenes (7.5 ± 0.2 µg/mL). The IC50 value was considerably high for the ovarian cell lines and human melanoma cell lines (426 µg/mL and 503 µg/mL). At 25 µg/mL concentration of lipopeptide, only 16.4% inhibition was observed in the ovarian cell line whereas 20.2% inhibition was achieved at this concentration in the human melanoma cell line. Lipopeptide inhibited bacterial growth and was completely inhibited at a concentration of 20 µg/mL. Lipopeptide reduced bacterial load in experimental mice compared to control (p < 0.05). CONCLUSION: Lipopeptide activity and its non-toxic nature reveal that it may serve as a lead molecule in the development of a novel drug.

Genome-Guided Investigation Provides New Insights into Secondary Metabolites of Streptomyces parvulus SX6 from Aegiceras corniculatum.

Whole-genome sequencing and genome mining are recently considered an efficient approach to shine more light on the underlying secondary metabolites of Streptomyces. The present study unearths the biosynthetic potential of endophytic SX6 as a promising source of biologically active substances and plant-derived compounds for the first time. Out of 38 isolates associated with Aegiceras corniculatum (L.) Blanco, Streptomyces parvulus SX6 was highly active against Pseudomonas aeruginosa ATCC® 9027™ and methicillin-resistant Staphylococcus epidermidis (MRSE) ATCC® 35984™. Additionally, S. parvulus SX6 culture extract showed strong cytotoxicity against Hep3B, MCF-7, and A549 cell lines at a concentration of 30 µg/ml, but not in non-cancerous HEK-293 cells. The genome contained 7.69 Mb in size with an average G + C content of 72.8% and consisted of 6,779 protein-coding genes. AntiSMASH analysis resulted in the identification of 29 biosynthetic gene clusters (BGCs) for secondary metabolites. Among them, 4 BGCs showed low similarity (28-67% of genes show similarity) to actinomycin, streptovaricin, and polyoxypeptin gene clusters, possibly attributed to antibacterial and anticancer activities observed. In addition, the complete biosynthetic pathways of plant-derived compounds, including daidzein and genistein were identified using genome mining and HPLC-DAD-MS analysis. These findings portray an exciting avenue for future characterization of promising secondary metabolites from mangrove endophytic S. parvulus.

Molecular Details of Actinomycin D-Treated MRSA Revealed via High-Dimensional Data.

Methicillin-resistant Staphylococcus aureus (MRSA) is highly concerning as a principal infection pathogen. The investigation of higher effective natural anti-MRSA agents from marine Streptomyces parvulus has led to the isolation of actinomycin D, that showed potential anti-MRSA activity with MIC and MBC values of 1 and 8 µg/mL, respectively. Proteomics-metabolomics analysis further demonstrated a total of 261 differential proteins and 144 differential metabolites induced by actinomycin D in MRSA, and the co-mapped correlation network of omics, indicated that actinomycin D induced the metabolism pathway of producing the antibiotic sensitivity in MRSA. Furthermore, the mRNA expression levels of the genes acnA, ebpS, clfA, icd, and gpmA related to the key differential proteins were down-regulated measured by qRT-PCR. Molecular docking predicted that actinomycin D was bound to the targets of the two key differential proteins AcnA and Icd by hydrogen bonds and interacted with multiple amino acid residues of the proteins. Thus, these findings will provide a basic understanding to further investigation of actinomycin D as a potential anti-MRSA agent.

Multi-Omics Analysis Reveals Anti-Staphylococcus aureus Activity of Actinomycin D Originating from Streptomyces parvulus.

Staphylococcus aureus (S. aureus) is a common pathogen that causes various serious diseases, including chronic infections. Discovering new antibacterial agents is an important aspect of the pharmaceutical field because of the lack of effective antibacterial drugs. In our research, we found that one anti-S. aureus substance is actinomycin D, originating from Streptomyces parvulus (S. parvulus); then, we further focused on the anti-S. aureus ability and the omics profile of S. aureus in response to actinomycin D. The results revealed that actinomycin D had a significant inhibitory activity on S. aureus with a minimum inhibitory concentration (MIC) of 2 µg/mL and a minimum bactericidal concentration (MBC) of 64 µg/mL. Bacterial reactive oxygen species (ROS) increased 3.5-fold upon treatment with actinomycin D, as was measured with the oxidation-sensitive fluorescent probe DCFH-DA, and H2O2 increased 3.5 times with treatment by actinomycin D. Proteomics and metabolomics, respectively, identified differentially expressed proteins in control and treatment groups, and the co-mapped correlation network of proteomics and metabolomics annotated five major pathways that were potentially related to disrupting the energy metabolism and oxidative stress of S. aureus. All findings contributed to providing new insight into the mechanisms of the anti-S. aureus effects of actinomycin D originating from S. parvulus.

Actinomycin-Producing Endophytic Streptomyces parvulus Associated with Root of Aloe vera and Optimization of Conditions for Antibiotic Production.

Endophytic actinomycetes are a rich source of novel antimicrobial compounds. The aim of this study was to evaluate the production of antimicrobial compound by endophytic Streptomyces sp. Av-R5 associated with root of Aloe vera against multidrug-resistant human pathogens. The 16S rRNA sequence of the isolate Av-R5 has been identified as Streptomyces parvulus NBRC 13193T (AB184326) and the sequence was submitted to the National Center for Biotechnology Information (NCBI) GenBank database (accession number KY771080). Streptomyces parvulus Av-R5 grown under submerged fermentation condition optimized by central composite design (glucose 11.16 g/L, soybean meal 10.25 g/L, sodium chloride 11.18 g/L, calcium carbonate 1.32 g/L at pH 7.19 at 31.42 °C with 6.04% seed inoculum for 10 days of incubation) exhibited the highest activity against multidrug-resistant Staphylococcus aureus JNMC-3, Staphylococcus epidermidis JNMC-4, Klebsiella pneumoniae MTCC-3384, Klebsiella pneumoniae JNMC-6, Pseudomonas aeruginosa MTCC-741, Proteus vulgaris JNMC-7, Candida albicans MTCC-183, and Aspergillus niger MTCC-872. The structures of the active compounds were elucidated by UV-Vis spectroscopy, 1H and 13C NMR, FT-IR, and ESIMS. Actinomycin D and actinomycin X0ß were detected in crude extracts and major components were eluted by HPLC at 10.96 and 6.81 min, respectively. In this case, a high yield of actinomycin D and actinomycin X0ß (400 mg/L) was achieved with Streptomyces parvulus Av-R5, fermented in glucose soybean meal broth media, which can be used in industrial fermentation process to obtain high yields.

Produção e caracterização de protease fibrinolítica de Streptomyces parvulus DPUA 1573 / Production and characterization of fibrinolytic protease from Streptomyces parvulus DPUA 1573

As proteases fibrinolíticas são capazes de degradar coágulos de fibrina formados dentro dos vasos sanguíneos, evitando a trombose intravascular. Em animais, a tromboflebite, que acomete frequentemente os equinos, ocasiona, em seus casos graves, a obstrução jugular e também um edema de laringe, derivando a obstrução das vias aéreas, o que possibilita um edema cerebral, ocorrendo o óbito do animal. Devido ao fato de o tratamento ser de custo elevado, faz-se necessária a investigação de outras fontesde proteases fibrinolíticas com custos menores e com menos efeitos colaterais. Diante disso, este estudo tem como objetivo produzir e caracterizar proteases fibrinolíticas obtidas de Streptomyces parvulus DPUA 1573. Para produção da enzima, foi utilizado um planejamento fatorial 24 avaliando a concentração da farinha de soja (0,5, 1,0 e 1,5%) e da glicose (0, 0,5 e 1,0g/L), temperatura (28, 32 e 37ºC) e agitação (150, 200 e 250rpm) sobre a biomassa e a atividade fibrinolítica. Pode-se verificar que a protease fibrinolítica apresentou atividade máxima (835U/mL) nas condições de concentração de 1,5% de soja, 1g/L de glicose, 28°C e 150rpm com 48 horas de fermentação. A protease fibrinolítica obtida teve temperatura e pH ótimos de 55°C e pH 9,0, respectivamente. A atividade enzimática foi inibida pelo EDTA, pelo íon Fe2+ e pelo SDS, o que indicou a enzima ser uma metaloprotease. A linhagem Streptomyces parvulus DPUA 1573 foi capaz de produzir protease fibrinolítica, possuindo características bioquímicas favoráveis à aplicação na medicina veterinária e possivelmente humana.(AU)

Fibrinolytic proteases are able to degrade fibrin clot formed in the blood vessel, avoiding intravascular thrombosis. In animals, thrombophlebitis often affects horses, and in severe cases causes obstruction of the jugular and laryngeal edema leading to airway obstruction allowing cerebral edema resulting in the death of the animal. Since treatment is costly, the investigation of other sources of fibrinolytic proteases at lower cost and with fewer side effects is needed. Thus, this study aims to produce and characterize fibrinolytic proteases from Streptomyces parvulus DPUA 1573. For enzyme production, a factorial design was performed to evaluate 24 soybean flour concentration (0.5, 1.0 and 1.5%) and glucose (0, 0.5 and 1.0g/L), temperature (28, 32 and 37°C) and agitation (150, 200 and 250rpm) on biomass and fibrinolytic activity. Fibrinolytic protease showed maximum activity (835 U/mL) under these conditions: 1.5% soybean flour, 1g/L glucose, 28°C, and 150rpm 48 hours of fermentation. The optimal temperature was 55°C and optimal pH was 9.0. Fibrinolytic protease activity was inhibited by EDTA, the ion Fe2+, and by SDS, which indicated that the enzyme is a metallo-protease. The strain Streptomyces parvulus DPUA 1573 was able to produce fibrinolytic protease with biochemical characteristics favorable for application in veterinary and human medicine.(AU)

Optimization of desferrioxamine E production by Streptomyces parvulus.

Siderophores are produced by a number of microbes to capture iron with outstandingly high affinity, which property also generates biomedical and industrial interests. Desferrioxamine E (DFO-E) secreted by streptomycetes bacteria can be an ideal candidate for iron chelation therapy, which necessitates its cost-effective production for in vitro and animal studies. This study focused on the optimization of DFO-E production by Streptomyces parvulus CBS548.68. Different combinations of various carbon and nitrogen sources as well as the addition of 3-morpholinopropane-1-sulfonic acid (MOPS) markedly affected DFO-E yields, which were attributed, at least in part, to the higher biomass productions found in MOPS-supplemented cultures. In MOPS-supplemented glucose and sodium glutamate medium, DFO-E productions as high as 2,009 ± 90 mg/l of culture medium were reached. High-performance liquid chromatography analysis demonstrated that a simple two-step purification process yielded DFO-E preparations with purities of ∼97%. Matrix assisted laser desorption ionization-time of flight mass spectrometry analysis showed that purified DFO-E always contained traces of desferrioxamine D2.

Atividade antimicrobiana de moléculas bioativas produzidas por Streptomyces parvulus DPUA 1573 frente a Staphylococcus spp. multirresistentes de mastite bubalina / Antimicrobial activity of bioactive molecules produced by Streptomyces parvulus DPUA 1573 against Staphylococcus spp. multi-drug resistant isolates from mastitis buffalo

A mastite é uma inflamação na glândula mamária que pode acarretar perdas na produção e na qualidade do leite, gerando prejuízos econômicos para a pecuária leiteira. O tratamento é baseado na utilização de antibióticos, sendo, em muitos casos, ineficazes devido à resistência bacteriana já conhecida para esta doença. O objetivo deste trabalho foi selecionar linhagens de Streptomyces spp. produtoras de biocompostos com atividade antimicrobiana frente a isolados do gênero Staphylococcus multirresistentes de búfalas com mastite. Bem como, determinar os melhores parâmetros de produção, e avaliar a produção simultânea de ácido clavulânico. A seleção de Streptomyces spp. com capacidade de produzir compostos com atividade antimicrobiana foi realizada através da técnica bloco de gelose. Dentre as 30 espécies de Streptomyces spp. testadas, o micro-organismo Streptomyces parvulus DPUA 1573 apresentou melhores resultados, sendo capaz de inibir o crescimento de 7 isolados Staphylococcus spp. multirresistentes. Posteriormente, a espécie selecionada Streptomyces parvulus DPUA 1573 foi cultivada em diferentes condições pré-determinadas pelo planejamento fatorial 24, onde as variáveis independentes foram: concentração de soja (0,5; 1,0; 1,5%), glicose (0; 0,5; 1g/L), agitação (150; 200; 250rpm) e temperatura (28; 32; 37°C) e todos os ensaios do planejamento foram monitorados até 120 horas de cultivo. Todas as variáveis independentes influenciaram positivamente no crescimento celular, enquanto que para atividade antimicrobiana apenas as variáveis temperatura e agitação apresentaram efeitos significativos positivos. O líquido metabólito produzido por Streptomyces parvulus DPUA 1573 foi capaz de inibir o crescimento de sete Staphylococcus spp. multirresistentes. As melhores condições de cultivo para a produção de moléculas bioativas por este micro-organismo foi a 37?C, com 250rpm de agitação por período de 72 horas. Nos ensaios que apresentaram atividade antimicrobiana, foi avaliada a produção de ácido clavulânico ao longo do cultivo. A maior concentração de ácido clavulânico foi de 269,84g/L obtidas nas condições de 1,5% de farinha de soja em ausência de glicose no tempo de 96 horas. A linhagem Streptomyces parvulus DPUA 1573 foi eficiente contra Staphylococcus spp. multirresistentes isolados de mastite em búfalas, ainda apresentando concomitantemente produção de ácido clavulânico com o potencial uso farmacêutico.(AU)

Mastitis is an inflammation in one or more mammary glands which can lead to reduction in production and quality of milk causing economic losses to dairy farming. The use of antibiotics is the key for the treatment of this disease, but in many cases ineffective due to bacterial resistance already known for this condition. The aim of this study was to select strains of Streptomyces spp. producing biomolecules with antimicrobial activity against multidrug-resistant Staphylococcus isolated from buffaloes with mastitis, as well as to determine the best production parameters to the evaluation of simultaneous production of clavulanic acid. Thirty species of Streptomyces spp. were used to selecting the greatest producer spectrum of antimicrobial activity (agar block technique), with selection of Streptomyces parvulus DPUA 1573, and 7 multidrug-resistant Staphylococcus spp. sensitive to its biocompounds. The selected strain of Streptomyces parvulus DPUA 1573 was cultured in different conditions predetermined by the factorial design 24, where the independent variables were: soybean concentration (0.5, 1.0, 1.5%), glucose (0, 0.5, 1g/L), agitation (150, 200, 250rpm) and temperature (28, 32, 37°C); all the tests were monitored up to 120 hours of cultivation. All independent variables influenced positively the cell growth, while for antimicrobial activity only the variables temperature and agitation showed positive effects. The antimicrobial bio compounds showed activity against seven multidrug-resistant Staphylococcus spp under the conditions: temperature 37°C, agitation 250rpm, with 72 hours of production process. In the tests which showed antimicrobial activity, was also assessed the production of clavulanic acid along with the cultivation. The highest concentration of clavulanic acid was 269.84g/L obtained under the conditions of 1.5% of soybean flour and absence of glucose in 96 hours. The strain Streptomyces parvulus DPUA 1573 was effective against multidrug-resistant strains of Staphylococcus spp. of mastitis from buffaloes, still showing concomitantly production of clavulanic acid for pharmaceutical use.(AU)

Antimicrobial Activity and Phylogenetic Analysis of Streptomyces Parvulus Dosmb-D105 Isolated from the Mangrove Sediments of Andaman Islands.

Actinomycetes, especially species of Streptomyces are prolific producers of pharmacologically significant compounds accounting for about 70% of the naturally derived antibiotics that are presently in clinical use. In this study, we used five solvents to extract the secondary metabolites from marine Streptomyces parvulus DOSMB-D105, which was isolated from the mangrove sediments of the South Andaman Islands. Among them, ethyl acetate crude extract showed maximum activity against 11 pathogenic bacteria and six fungi. Presence of bioactive compounds in the ethyl acetate extract was determined using GC-MS and the compounds detected in the ethyl acetate extract were matched with the National Institute of Standards and Technology (NIST) library. Totally eight compounds were identified and the prevalent compounds were 2 steroids, 2 alkaloids, 2 plasticizers, 1 phenolic and 1 alkane. Present study revealed that S. parvulus DOSMB-D105 is a promising species for the isolation of valuable bioactive compounds to combat pathogenic microbes.

Antimicrobial, Antioxidant and Cytotoxic Activity of Marine Streptomyces parvulus VITJS11 Crude Extract

The main aim of the study was to evaluate the bioactive properties of ethyl acetate crude extract of Streptomyces parvulus VITJS11 with a view to assess their therapeutic potential. The biological activity of ethyl acetate extract was tested against fungal and bacterial pathogens. The free radical scavenging potential of the crude extract was determined by DPPH assay. The chemo preventive properties of S. parvulus VITJS11 ethyl acetate extract was examined by MTT assay on HepG2 cells. The morphological, physiological and the biochemical properties of the strain S. parvulus VITJS11 was confirmed by conventional methods. Genotypic characterization was done using 16S r-DNA partial gene amplification and sequencing. The authenticity of the crude chemical constitutes were determined by the GC-MS. The ethyl acetate extract of VITJS11 showed maximum antifungal activity against three Aspergillus species and prominent antibacterial activity against two Gram positive and Gram negative bacteria at 20 mg/mL. The antioxidant potential of the crude extract exhibited strong reducing power activity at 5mg/ mL with 85% inhibition and the cytotoxic effect was found with IC50 of 500µg/ mL on HepG2 cell lines. The GC-MS analysis and the chromatogram patterns revealed 16 peaks, indicating the presence of bioactive constituents, which included several important organic compounds, namely 9-(2',2'-dimethylpropanoilhydrazono)-3,6-dichloro-2,7-Bis-[2-(diethylamino)-ethoxy]fluorine (23.1) Dotriacontylpentafluoropropionate,(25.0) Octadecanoic acid, (20.0); Trans-2-methyl-4-n-butylthiane, S, S-dioxide.(19.0). The results showed the benefit of ethyl acetate extract from S. parvulus VITJS11 in treating microbial infections and indicated their broad spectrum of activity with beneficial virtues for therapeutic use.

Production and Characterization of Protein Encapsulated Silver Nanoparticles by Marine Isolate Streptomyces parvulus SSNP11.

Production of protein encapsulated silver nanoparticles (AgNPs) assisted by marine actinomycetes strain has been investigated. The selective isolate was identified as Streptomyces parvulus SSNP11 based on chemotaxonomic and 16S rRNA analysis. Maximum AgNPs production was observed within 24 h incubation time. The produced AgNPs are spherical in shape with monodispersive and crystalline in nature. The particle size distribution ranges from 1.66 to 11.68 nm with a mean size of 2.1 nm. The biosynthesized AgNPs revealed stretching vibrations of primary and secondary amines along with C-H and C-N, suggesting that metabolically produced proteins are involved in size regulation of reduced AgNPs. These particles possess an average negative zeta potential value of 81.5 mV with an electrophoretic mobility of 0.000628 cm(2)/Vs. The biosynthesized nanoparticles revealed antimicrobial property against gram negative as well as gram positive bacterial strains.

Production of polypeptide antibiotic from Streptomyces parvulus and its antibacterial activity.

A highly potent secondary metabolite producing actinomycetes strain is isolated from marine soil sediments of Visakhapatnam sea coast, Bay of Bengal. Over all ten strains are isolated from the collected soil sediments. Among the ten actinomycetes strains the broad spectrum strain RSPSN2 was selected for molecular characterization, antibiotic production and its purification. The nucleotide sequence of the 1 rRNA gene (1261 base pairs) of the most potent strain evidenced a 96% similarity with Streptomyces parvulus 1044 strain, Streptomyces parvulus NBRC 13193 and Streptomyces parvulus BY-F. From the taxonomic features, the actinomycetes isolate RSPSN2 matches with Streptomyces parvulus in the morphological, physiological and biochemical characters. Thus, it was given the suggested name Streptomyces parvulus RSPSN2. The active metabolite was extracted using ethyl acetate (1:3, v/v) at pH 7.0. The separation of active ingredient and its purification was performed by using both thin layer chromatography (TLC) and column chromatography (CC) techniques. Spectrometric studies such as UV-visible, FTIR, and NMR and mass were performed. The antibacterial activity of pure compound was performed by cup plate method against some pathogenic bacteria including of streptomycin resistant bacteria like (Pseudomonas mirabilis, Pseudomonas putida and Bacillus cereus). In conclusion, the collected data emphasized the fact that a polypeptide antibiotic (Actinomycin D) was produced by Streptomyces parvulus RSPSN2.

Production of polypeptide antibiotic from Streptomyces parvulus and its antibacterial activity

A highly potent secondary metabolite producing actinomycetes strain is isolated from marine soil sediments of Visakhapatnam sea coast, Bay of Bengal. Over all ten strains are isolated from the collected soil sediments. Among the ten actinomycetes strains the broad spectrum strain RSPSN2 was selected for molecular characterization, antibiotic production and its purification. The nucleotide sequence of the 1 rRNA gene (1261 base pairs) of the most potent strain evidenced a 96% similarity with Streptomyces parvulus 1044 strain, Streptomyces parvulus NBRC 13193 and Streptomyces parvulus BY-F. From the taxonomic features, the actinomycetes isolate RSPSN2 matches with Streptomyces parvulus in the morphological, physiological and biochemical characters. Thus, it was given the suggested name Streptomyces parvulus RSPSN2. The active metabolite was extracted using ethyl acetate (1:3, v/v) at pH 7.0. The separation of active ingredient and its purification was performed by using both thin layer chromatography (TLC) and column chromatography (CC) techniques. Spectrometric studies such as UV-visible, FTIR, and NMR and mass were performed. The antibacterial activity of pure compound was performed by cup plate method against some pathogenic bacteria including of streptomycin resistant bacteria like (Pseudomonas mirabilis. Pseudomonas putida and Bacillus cereus). In conclusion, the collected data emphasized the fact that a polypeptide antibiotic (Actinomycin D) was produced by Streptomyces parvulus RSPSN2.