Yemenimycin

Yemenimycin (I) (0.0012-0.12 μg/ml) isolated from cultures of Streptomyces AS-Y-52 inhibited the incorporation of phosphorus-32 [14596-37-3] into DNA and RNA, but stimulated the incorporation of labeled supplement into the TCA soluble fraction and phospholipids of Candida albicans cells.Glycolysis and aerobic respiration were less sensitive to the antibiotic than the synthesis of nucleic acids and proteins.I inhibited the incorporation of 14C-labeled thymidine [50-89-5] and to a lesser extent that of 14C-labeled uridine [58-96-8] into DNA and RNA of Bacillus subtilis cells; the incorporation of 3H-labeled lysine [56-87-1] into cellular protein was the most resistant to I.I inhibited protein synthesis in rabbit reticulocytes.

A new antibiotic, named yemenimycin (I), was isolated from the broth and mycelial pellets of Streptomyces AS-Y-52.I inhibited the growth of gram-pos. bacteria and fungi, but had little activity against gram-neg. bacteria.The min. inhibitory concentration was 0.006-0.78 μg/ml.Candida, Trichophyton, and microsporum were highly sensitive; also Staphylococcus and Bacillus.I is a polypeptide, soluble in most organic solvents, but not in H2O and petroleum ether.In shaken cultures in a starch-salts medium at 28°, maximum yield was obtained after 6 days.I was isolated as pale yellowish-buff minute needles, m.p. 212-14°, very soluble in CHCl3, Me2O, EtOAc, and BuOAc, and moderately soluble in MeOH, EtOH, and BuOH.Ir and uv spectra, paper chromatog., and chem. reactions and composition were described.