Protein is the executor of physiological function, and direct embodiment of the life phenomena. Proteomics aims to systematically clarify all or parts of proteins' role and function in life movement. In post genome era, proteomics began to play more important role in life science field. Actinobacteria are closely linked to human production and life, which have produced many clinically important secondary metabolites, including antibiotics, antitumorals and enzymes. Actinobacterial systematics and its model organism Streptomyces coelicolor in 2001 genome sequence laid the foundation for further functional genomic studies. Actinobacterial proteomics was more directly and exactly to interpret the activity of life than genomics and transcriptomics, which grew much faster and received so much attention from scientists in the near years. Complex morphological differention, stronge environment adaptiveness, nitrogen-fixing capacity, metabolic mechanism, pathogenicity and natural produces' discovery were systematically reviewed in this study, which was expected to be the basis for promoting Actinobacterial proteomics study in the near future.
Actinobacteria ; genetics ; metabolism ; Genomics ; Proteomics ; Streptomyces coelicolor ; genetics ; metabolism

Cyclodipeptide (CDP) composed of two amino acids is the simplest cyclic peptide. These two amino acids form a typical diketopiperazine (DKP) ring by linking each other with peptide bonds. This characteristic stable ring skeleton is the foundation of CDP to display extensive and excellent bioactivities, which is beneficial for CDPs' pharmaceutical research and development. The natural CDP products are well isolated from actinomycetes. These bacteria can synthesize DKP backbones with nonribosomal peptide synthetase (NRPS) or cyclodipeptide synthase (CDPS). Moreover, actinomycetes could produce a variety of CDPs through different enzymatic modification. The presence of these abundant and diversified catalysis indicates that actinomycetes are promising microbial resource for exploring CDPs. This review summarized the pathways for DKP backbones biosynthesis and their post-modification mechanism in actinomycetes. The aim of this review was to accelerate the genome mining of CDPs and their isolation, purification and structure identification, and to facilitate revealing the biosynthesis mechanism of novel CDPs as well as their synthetic biology design.
Actinobacteria/metabolism* ; Actinomyces/metabolism* ; Biological Products/metabolism* ; Bacteria/metabolism* ; Diketopiperazines/metabolism* ; Amino Acids

One strain F05 which had better antagonism for American ginseng rust rot was obtained from continuous cropping ground, and its fermentation had been preliminarily studied, more over the research can further determine the optimum composition. The single factor and uniform design were used to optimize the formulation medium. The identified formulation was powder of cornstalks 3.7206%, (NH4)2HPO4 0.5312%, MgSO4 0.0355%, K2HPO4 0.0400%. The bacteria number was 1.57 x 10(9) per milliliter culture solution.
Actinobacteria ; chemistry ; isolation & purification ; metabolism ; Culture Media ; chemistry ; metabolism ; Fermentation ; Panax ; microbiology ; Plant Diseases ; microbiology

Ribosomal engineering is a technique that can improve the biosynthesis of secondary metabolites in the antibiotics-resistant mutants by attacking the bacterial RNA polymerase or ribosome units using the corresponding antibiotics. Ribosomal engineering can be used to discover and increase the production of valuable bioactive secondary metabolites from almost all actinomycetes strains regardless of their genetic accessibility. As a consequence, ribosomal engineering has been widely applied to genome mining and production optimization of secondary metabolites in actinomycetes. To date, more than a dozen of new molecules were discovered and production of approximately 30 secondary metabolites were enhanced using actinomycetes mutant strains generated by ribosomal engineering. This review summarized the mechanism, development, and protocol of ribosomal engineering, highlighting the application of ribosomal engineering in actinomycetes, with the aim to facilitate future development of ribosomal engineering and discovery of actinomycetes secondary metabolites.
Actinobacteria/metabolism* ; Actinomyces/genetics* ; Anti-Bacterial Agents/metabolism* ; Multigene Family ; Ribosomes/genetics*

To explore the effect of coculturing actinomycetes with Bacillus subtilis on the production of bioactive secondary metabolites, we studied the difference between fermentation products of monocultures and the corresponding cocultures of 22 actinomycetes by antimicrobial assay and HPLC-PDA analysis. We selected Streptomyces strain FXJ2.014 with high bioactivity for further analysis and found additional metabolites in fermentation extracts of cocultures of strains FXJ2.014, FXJ1.296 and AS 4.1252 respectively with B. subtilis. Quinomycin A was the main bioactive metabolite produced by the monoculture of strain FXJ2.014, while a new quinomycin-like component named FXJ2.014-HB was produced when strain FXJ2.014 was cocultured with B. subtilis. Further tests of antimicrobial and antitumor activities indicated that FXJ2.014-HB and Quinomycin A had significant differences in terms of bioactivity. Moreover, the inhibitory activity of FXJ2.014-HB to a variety of tumor cell lines was weaker than the highly toxic Quinomycin A, indicating its potential to be an antibiotic with low cell toxicity. In conclusion, coculture can be used as a promising approach to discover bioactive secondary metabolites from actinomycetes.
Actinobacteria ; growth & development ; metabolism ; Anti-Bacterial Agents ; biosynthesis ; Bacillus subtilis ; growth & development ; metabolism ; Coculture Techniques ; Streptomyces ; growth & development ; metabolism

OBJECTIVETo study the characteristics of soil microbial variation during Salvia miltiorrhiza crop rotation.

METHODthe conventional cultivating microbial method was used to study the microbial number and communities structure and soil microbial biomass phosphorus (SMBP) was determined by chloroform vapor extraction method. The data was then analyzed by SPSS software.

RESULTWith the increase of the crop rotation years, the numbers of bacteria and actinomycetes in soil also, but the fungi and SMBP decreased.

CONCLUSIONMicrobial mechanism of crop rotation of the planting S. miltiorrhiza is the regulation of microbial number and bacteria physiological communities, the process rebuilds the soil ecological system balance. Microbial communities in soil need at lest 2 years to get to restore, after planting S. miltiorrhiza, which consisting with traditional planting experience.

Actinobacteria ; isolation & purification ; Bacteria ; isolation & purification ; Plants, Medicinal ; growth & development ; metabolism ; microbiology ; Salvia miltiorrhiza ; growth & development ; metabolism ; microbiology ; Soil Microbiology

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

The isoflavonol glycoside Talosin A, genistein (GT)-7-alpha-L-6-deoxy talopyranose (GT-Tal), was first isolated from the culture broth of Kitasatospora kifunensis MJM341. The aim of the present study was to evaluate the oral absorption and metabolism of the newly isolated isoflavonol glycoside, GT-Tal compared to genistin (GT-7-O-beta-D-glucopyranoside; GT-Glu). Free GT-Glu and GT-Tal could not be detected prior to enzymatic hydrolysis of the corresponding conjugates in rat plasma. Following oral administration of GT-Tal (15 min), GT-Tal was rapidly absorbed through the gastrointestinal tract and metabolized into GT-Tal conjugates with a mean Cmax of 2.74 microg/mL. GT-Tal was further metabolized to its aglycone, free GT and conjugated GT. After oral administration, GT-Glu was absorbed after being convereted to its aglycone and then further metabolized into its conjugate metabolites (free GT with a mean Cmax of 0.24 mg/mL at 1.25 h; conjugated GT with a mean Cmax of 1.31 mg/mL at 2.00 h). Significant differences in absorption and metabolism of GT-Tal and GT-Glu were observed. GT-Tal was metabolized into its corresponding conjugates or underwent deglycosylation to form GT, whereas GT-Glu was metabolized into its aglycone, GT.
Actinobacteria/*chemistry ; Administration, Oral ; Animals ; Area Under Curve ; Glycosides/administration & dosage/*metabolism/pharmacokinetics ; Hydrolysis ; Intestinal Absorption ; Isoflavones/administration & dosage/*metabolism/pharmacokinetics ; Male ; Random Allocation ; Rats ; Rats, Sprague-Dawley

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