Nocathiacin I, a glycosylated thiopeptide antibiotic, displays excellent antibacterial activities against multidrug resistant bacterial pathogens. Previously, a novel nocathiacin I formulation for intravenous administration has been successfully developed and its aqueous solubility is greatly enhanced for clinical application. The purpose of the present study was to increase the fermentation titer of nocathiacin I and reduce or eliminate analogous impurities by screening the medium ingredients using response surface methodology. After a sysmatic optimization, a water-soluble medium containing quality-controllable components was developed and validated, resulting in an increase in the production of nocathiacin I from 150 to 405.8 mg·L at 150-L scale. Meanwhile, the analogous impurities existed in reported processes were greatly reduced or eliminated. Using optimized medium for fermentation, nocathiacin I with pharmaceutically acceptable quality was easily obtained with a recovery of 67%. In conclusion, the results from the present study offer a practical and efficient fermentation process for the production of nocathiacin I as a therapeutic agent.
Actinobacteria ; growth & development ; metabolism ; Anti-Bacterial Agents ; biosynthesis ; chemistry ; Bioreactors ; Culture Media ; Fermentation ; Intercellular Signaling Peptides and Proteins ; Peptides ; chemistry ; metabolism ; Quality Improvement

In this paper, actinomycetes were isolated from vermicompost by tablet coating method. Antimicrobial activities of actinomycetes were measured by the agar block method. Strains with high activity were identified based on morphology and biochemical characteristics, as well as 16S rDNA gene sequence analysis. The results showed that 26 strains of actinomycetes were isolated, 16 of them had antimicrobial activities to the test strains which accounts for 61.54% of all strains. Among the 16 strains, the strain QYF12 and QYF22 had higher antimicrobial activity to Micrococcus luteus, with a formed inhibition zone of 27 mm and 31 mm, respectively. While the strain QYF26 had higher antimicrobial activity to Bacillus subtilis, and the inhibition zone diameter was 21 mm. Based on the identification of strains with high activity, the strain QYF12 was identified as Streptomyces chartreusis, the strain QYF22 was S. ossamyceticus and the strain QYF26 was S. gancidicus. This study provided a theoretical basis for further separate antibacterial product used for biological control.
Actinobacteria ; chemistry ; classification ; genetics ; isolation & purification ; Animals ; Anti-Bacterial Agents ; isolation & purification ; metabolism ; Bacteria ; drug effects ; Feces ; microbiology ; Molecular Sequence Data ; Oligochaeta ; Phylogeny ; Quality Control

Three new compounds, namely siderochelins D (2), E (3), and F (4), together with one known siderochelin A (1), were isolated from Amycolatopsis sp. LZ149 and elucidated by spectroscopic analyses including1D- and 2D-NMR and X-ray single crystal diffraction. Compounds 1-3 showed antibacterial activity against Mycobacterium smegmatis.
Actinobacteria ; chemistry ; Anti-Infective Agents ; pharmacology ; Dihydropyridines ; isolation & purification ; Magnetic Resonance Spectroscopy ; Microbial Sensitivity Tests ; Molecular Structure ; Mycobacterium smegmatis ; drug effects

The present study was designed to determine the taxonomic diversity and metabolic activity of the actinomycetes community, including 13 traditional medicinal plants collected in Sichuan province, China, using multiple approaches such as morphological and molecular identification methods, bioactivity assays, and PCR screening for genes involved in antibiotics biosynthesis. 119 endophytic actinomycetes were recovered; 80 representative strains were chosen for 16S rRNA gene partial sequence analyses, with 66 of them being affiliated to genus Streptomyces and the remaining 14 strains being rare actinomycetes. Antimicrobial tests showed that 12 (15%) of the 80 endophytic actinomycetes displayed inhibitory effects against at least one indicator pathogens, which were all assigned to the genus Streptomyces. In addition, 87.5% and 58.8% of the isolates showed anticancer and anti-diabetic activities, respectively. Meanwhile, the anticancer activities of the isolates negatively correlated with their anti-diabetic activities. Based on the results of PCR screening, five genes, PKS-I, PKS-II, NRPS, ANSA, and oxyB, were detected in 55.0%, 58.8%, 90.0%, 18.8% and 8.8% of the 80 actinomycetes, respectively. In conclusion, the PCR screening method employed in the present study was conducive for screening and selection of potential actinomycetes and predicting potential secondary metabolites, which could overcome the limitations of traditional activity screening models.
Actinobacteria ; chemistry ; classification ; isolation & purification ; metabolism ; Biodiversity ; China ; Endophytes ; chemistry ; classification ; isolation & purification ; metabolism ; Molecular Sequence Data ; Phylogeny ; Plants, Medicinal ; classification ; microbiology ; Secondary Metabolism

To reveal the effect of rotation cropping and bacterial manure on the growth of Chrysanthemum morifolium and screen the beneficial endophytic, the diversity of endophytic and dominant genera of different treatment groups were analyzed. Four different treatments were continuous cropping, rotation, self-made organic fertilizer and commercially available fertilizer, respectively. Endophytic bacterial diversity and dominant genera in different organs were examined using Terminal Restriction Fragment Length Polymorphism (T-RFLP). The results showed that enzyme Hae III was more appropriate than enzyme Hinfl because the number of TRFs digested by enzyme Hae III was more than that of enzyme Hinfl. In comparison of diversity, the endophytic bacterial communities' diversity index in group of cropping rotation and fertilizer was higher than that of continuous cropping which indicated that the addition of exogenous microorganism in soil could increase the diversity of plant endophyte. 18 dominant species were selected, including 3 kinds of Firmicutes, 4 kinds of Actinomycetes and 11 kinds of Proteobacteria. The results of dominant species comparison showed that the number of dominant species in continuous cropping of Ch. morifolium was significantly less than that of the rotation group. Some dominant bacteria in rotation group and fertilizer group such as Arthrobacter, Streptomyces, Streptomyces, Flavobacterium and Mycobacterium were not found in the continuous cropping of Ch. mortfolium group. Dominant species of fertilizer treatment group was similar with the rotation group, and the continuous cropping group's dominant species was more abundant. It indicates that these bacteria may be able to mitigate hindrance in continuous cropping, especially the Flavobacterium which can decompose the pathogenic fungi is worthy of further attention. Compared with leaves, there are more dominant species in roots and stems. The diversity of edophytic bacterial communities in continuous cropping of Ch. morifolium stays below than that in the rotation of Ch. morifolium, and fertilizer treatment can increase the diversity of continuous cropping so that it could mitigate hindrance in continuous cropping.
Actinobacteria ; physiology ; Agriculture ; Biodiversity ; Chrysanthemum ; growth & development ; microbiology ; Deoxyribonucleases, Type II Site-Specific ; Endophytes ; Fertilizers ; Gram-Positive Bacteria ; physiology ; Phylogeny ; Plant Leaves ; Plant Roots ; microbiology ; Polymorphism, Restriction Fragment Length ; Proteobacteria ; physiology ; RNA, Ribosomal, 16S ; chemistry ; genetics ; Soil ; Soil Microbiology

No abstract available.
Actinobacteria/genetics/*isolation & purification ; Bacteremia/*diagnosis/microbiology ; Humans ; Male ; Middle Aged ; Polymerase Chain Reaction ; RNA, Ribosomal, 16S/chemistry/genetics ; Republic of Korea ; Sequence Analysis, RNA ; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization

In the last decade, along with the development of taxonomy research in marine-derived actinobacteria, more and more halogenated natural products were discovered from marine actinobacteria. Most of them showed good biological activity and unique structure compared to those from land. The special halogenation mechanism in some compounds' biosynthesis has drawn great attention. So in this review, we focus on the halogenated natural products from marine actinobacteria and their halogenation mechanisms.
Actinobacteria ; chemistry ; Anti-Bacterial Agents ; chemistry ; isolation & purification ; pharmacology ; Antineoplastic Agents ; chemistry ; isolation & purification ; pharmacology ; Biological Products ; chemistry ; isolation & purification ; pharmacology ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Halogenation ; Humans ; Marine Biology ; Molecular Structure

OBJECTIVETo isolate novel actinomycetes and to evaluate their antibacterial activity.

METHODSThree soil samples were collected from Vengodu (village) in Kanchipuram district, Tamil Nadu, India. Actinomycetes were isolated using serial dilution and plating method on actinomycetes isolation agar.

RESULTSTotally 35 isolates were obtained on the basis of colony characteristics on actinomycetes isolation agar. All the isolates were screened for antibacterial activity by cross streak method. Medium and optimization of day were done for the potent strains using Nathan's agar well diffusion method. Isolation of bioactive compounds from significant active isolates was done by using different media. The most active isolate VAS 10 was identified as Actinobacterium Loyola PBT VAS 10 (accession No. JF501398) using 16s rRNA sequence method. The hexane, ethyl acetate, dichloromethane and butanol extracts of VAS 10 were tested against bacteria. The maximum antibacterial activity was observed in dichloromethane and ethyl acetate; maximum zones of inhibition were observed against Enterococcus durans. The rRNA secondary structure and the restriction sites of Actinobacterium Loyola VAS 10 were predicted using Genebee and NEBCutter online tools respectively.

CONCLUSIONSThe present study showed that among the isolated actinomycetes, Actinobacterium Loyola PBT VAS 10 (accession No. JF501398) showed good antibacterial activity against the tested bacteria.

Actinobacteria ; chemistry ; isolation & purification ; physiology ; Animals ; Anti-Bacterial Agents ; pharmacology ; Antibiosis ; physiology ; Bacillus subtilis ; drug effects ; Enterobacter aerogenes ; drug effects ; Escherichia coli ; drug effects ; India ; Microbial Sensitivity Tests ; Phylogeny ; RNA, Ribosomal, 16S ; genetics ; Soil Microbiology ; Species Specificity ; Vibrio parahaemolyticus ; drug effects

OBJECTIVETo isolate and indentify the promising antimicrobial metabolite producing Streptomyces strains from marine sediment samples from Andrapradesh coast of India.

METHODSAntagonistic actinomycetes were isolated by starch casein agar medium and modified nutrient agar medium with 1% glucose used as a base for primary screening. Significant antimicrobial metabolite producing strains were selected and identified by using biochemical and 16S rDNA level. Minimum inhibitory concentrations of the organic extracts were done by using broth micro dilution method.

RESULTSAmong the 210 actinomycetes, 64.3% exhibited activity against Gram positive bacteria, 48.5 % showed activity towards Gram negative bacteria, 38.8% exhibited both Gram positive and negative bacteria and 80.85 % isolates revealed significant antifungal activity. However, five isolates AP-5, AP-18, AP-41 and AP-70 showed significant antimicrobial activity. The analysis of cell wall hydrolysates showed the presence of LL-diaminopimelic acid and glycine in all the isolates. Sequencing analysis indicated that the isolates shared 98.5%-99.8% sequence identity to the 16S rDNA gene sequences of the Streptomyces taxons. The antimicrobial substances were extracted using hexane and ethyl acetate from spent medium in which strains were cultivated at 30°Cfor five days. The antimicrobial activity was assessed using broth micro dilution technique. Each of the culture extracts from these five strains showed a typical polyene-like property. The lowest minimum inhibitory concentrations of ethyl acetate extracts against Escherichia coli and Curvularia lunata were 67.5 and 125.0 µg/mL, respectively.

CONCLUSIONSIt can be concluded that hexane and ethyl acetate soluble extracellular products of novel isolates are effective against pathogenic bacteria and fungi.

Actinobacteria ; chemistry ; classification ; genetics ; isolation & purification ; Anti-Bacterial Agents ; chemistry ; pharmacology ; Anti-Infective Agents ; chemistry ; pharmacology ; Antifungal Agents ; chemistry ; pharmacology ; Bays ; Complex Mixtures ; chemistry ; pharmacology ; Geologic Sediments ; microbiology ; India ; Microbial Sensitivity Tests ; Molecular Sequence Data ; Phylogeny ; Polyenes ; chemistry ; pharmacology ; RNA, Ribosomal, 16S ; genetics

OBJECTIVETo investigate the antibacterial activity of marine actinobacteria against multidrug resistance Staphylococcus aureus (MDRSA).

METHODSFifty one actinobacterial strains were isolated from salt pans soil, costal area in Kothapattanam, Ongole, Andhra Pradesh. Primary screening was done using cross-streak method against MDRSA. The bioactive compounds are extracted from efficient actinobacteria using solvent extraction. The antimicrobial activity of crude and solvent extracts was performed using Kirby-Bauer method. MIC for ethyl acetate extract was determined by modified agar well diffusion method. The potent actinobacteria are identified using Nonomura key, Shirling and Gottlieb 1966 with Bergey's manual of determinative bacteriology.

RESULTSAmong the fifty one isolates screened for antibacterial activity, SRB25 were found efficient against MDRSA. The ethyl acetate extracts showed high inhibition against test organism. MIC test was performed with the ethyl acetate extract against MDRSA and found to be 1 000 µg/mL. The isolated actinobacteria are identified as Streptomyces sp with the help of Nonomura key.

CONCLUSIONSThe current investigation reveals that the marine actinobacteria from salt pan environment can be able to produce new drug molecules against drug resistant microorganisms.

Actinobacteria ; chemistry ; isolation & purification ; Anti-Infective Agents ; chemistry ; pharmacology ; Complex Mixtures ; chemistry ; pharmacology ; Drug Resistance, Multiple, Bacterial ; Geologic Sediments ; microbiology ; Microbial Sensitivity Tests ; Staphylococcus aureus ; drug effects