| Popis: |
Streptomyces antibioticus synthesizes several new actinomycins when dl-pipecolic acid is provided in the culture medium. Three of the compounds (Pip 2, Pip 1α, and Pip 1β) were isolated, purified, and characterized. Amino acid hydrolysates revealed that these antibiotics contain threonine, valine, sarcosine, and N-methylvaline but differ from actinomycins normally synthesized in the imino acid site of the molecule. The data reveal that: actinomycin Pip 2 contains 2 residues of pipecolic acid, actinomycin Pip 1β possesses 1 residue each of pipecolic acid and proline, and actinomycin Pip 1α contains pipecolic acid and 4-oxopipecolic acid per mole of actinomycin. 4-Oxopipecolic acid is a normal constituent of a number of peptide antibiotics, e.g. ostreogrycin, vernamycin Bα, and staphylomycin. |
