A novel series of milbemycin antibiotics from Streptomyces strain E225. II. Isolation, characterization, structure elucidation and solution conformations.

A novel series of milbemycin antibiotics were isolated from the fermentation broth of a Streptomyces species designated E225. The structures of the four main metabolites VM 44857 (1), VM 44864 (2), VM 44865 (3) and VM 44866 (4) were determined by NMR techniques. In addition we describe the solution conformations of the major metabolite VM 44857 (1).

A novel series of milbemycin antibiotics from Streptomyces strain E225. I. Discovery, fermentation and anthelmintic activity.

A novel series of milbemycin antibiotics were produced by soil isolate, strain E225 which was shown to be a Streptomyces species. The antibiotics displayed anthelmintic activity against Trichostrongylus colubriformis in the gerbil. Two of the compounds, VM 44857 and VM 44866 were shown to be potent anthelmintics against mixed nematode infections in sheep.

Some characteristics of mycoplasma virus Hr 1, isolated from and infecting Mycoplasma hyorhinis. Brief report.

Mycoplasma virus Hr 1 is a short tailed bacteriophage with a polyhedral head about 34 nm across and a tail about 14 nm long. It produces plaques on some strains of Mycoplasma hyorhinis.