A group of antibiotic substances produced by Streptomyces variants. They are composed of an aminosugar and different polypeptide chains and may have broad spectrum antimicrobial and some antiviral properties. Streptothricin antibiotic Nourseothricin (NTC) is used for a broad spectrum of viruses, bacteria and other unicellular or complex organisms. Preferred selection antibiotic for genetically modified Gram-positive and Gram-negative bacteria, yeast, filamentous fungi, protozoa, plants and many more. Selection of recombinant strains is based on inactivation of NTC by monoacetylation of ß-amino group of the ß-lysine by Nouresothricin N-acetyltransferase the product of the sat1 gene.||Applications:|Suitable for use in selection of recombinant Leishmania strains.||Recommended Dilutions: |Add to growth medium to a final concentration of 100ug/ml.|Optimal dilutions to be determined by the researcher.||PubChem Chemical ID:|Streptothricin D: 202550, Streptothricin F: 197034||Table 1:|* MIC: Minimal inhibitory concentration|** IC50: Concentration inhibiting growth by 50%||Group Species MIC* Selection conc. | ug/ml ug/ml|Gram-negative bacteria |Escherichia coli 2-12 50|Francisella tularensis - 5|Pseudomonas aeruginosa 50 100|Gram-positive bacteria |Bacillus subtilis 5 50|Enterococcus faecium 8-256 500|Staphylococcus aureus -12 50|Streptomycetes |Streptomyces lividans 6 100|Yeast |Candida albicans 200 250-450|Cryptococcus neoformans - 100|Hansenula polymorpha - 100|Pichia pastoris - 100|Saccharomyces cerevisiae 25 100|Filamentous fungi |Acremonium chrysogenum - 25|Sordaria macrospora - 50|Ustilago maydis - 75|Protozoa Leishmania tarentolae - 100|Phytomonas serpens - 100|Plasmodium falciparum 75* -|Toxoplasma gondii - 500|Plants |Arabidopsis thaliana 20 200|Oryza sativa 20 200||Storage and Stability:|May be stored at 4°C for short-term only. Aliquot to avoid repeated freezing and thawing. Store at -20°C. Stable for 6 months after receipt.. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap