Toyocamycin exhibits effective biological activities for use against plant pathogenic fungi thanks to its structural similarity to nucleoside. It has been recognized as a promising agricultural antibiotic utilized in controlling the occurrence of plant diseases. In our previous study, a strain that was isolated was identified and designated as Streptomyces diastatochromogenes whose major secondary metabolite was toyocamycin, but the production was largely limited. Protoplast transformation is a useful technique in the improvement of streptomycete. In this study, we optimized some key factors necessary for protoplast formation, regeneration, and transformation of S. diastatochromogenes. When mycelium was cultivated in CP medium with 1 % glycine, harvested at 48 h old, and then treated with 3 mg lysozyme/mL in P buffer for 1 h, the greatest regeneration frequency (42.5 %) of protoplasts was obtained. By using 1 × 10(9)/mL protoplasts with polyethylene glycol 1000 at a concentration of 30 % (w/v), the best performance of protoplast transformation efficiency was 4.8 × 10(3)/μg DNA transformants.
Streptomycetes, soil-dwelling mycelial bacteria, can colonise surface of organic soil debris and soil particles. We analysed the effects of two different inert surfaces, glass and zirconia/silica, on the growth and antibiotic production in Streptomyces granaticolor. The surfaces used were in the form of microbeads and were surrounded by liquid growth media. Following the production of the antibiotic granaticin, more biomass was formed as well as a greater amount of antibiotic per milligram of protein on the glass beads than on the zirconia/silica beads. Comparison of young mycelium (6 h) proteomes, obtained from the cultures attached to the glass and zirconia/silica beads, revealed three proteins with altered expression levels (dihydrolipoamide dehydrogenase, amidophosphoribosyltransferase and cystathionine beta-synthase) and one unique protein (glyceraldehyde-3-phosphate dehydrogenase) that was present only in cells grown on glass beads. All of the identified proteins function primarily as cytoplasmic enzymes involved in different parts of metabolism; however, in several microorganisms, they are exposed on the cell surface and have been shown to be involved in adhesion or biofilm formation.
- MeSH
- antibakteriální látky metabolismus MeSH
- bakteriální adheze * MeSH
- bakteriální proteiny biosyntéza MeSH
- biomasa MeSH
- exprese genu MeSH
- hydrofobní a hydrofilní interakce * MeSH
- imobilizované buňky chemie metabolismus fyziologie MeSH
- naftochinony metabolismus MeSH
- povrchové vlastnosti * MeSH
- Streptomyces chemie růst a vývoj fyziologie MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
