316
MAURICE WELSCH
derivative of cycloheximide, antibiotic E-73, is an antitumor agent produced by S. albulus. It is highly toxic, but potentially useful derivatives
are being studied (280). Inactone is a biologically inactive 1,6-dehydrocycloheximide produced by S. griseus. The equally inactive actiphenol,
a closely related compound in which the cyclohexyl moiety is replaced
by an aromatic ring (CXXI), was isolated from the cultures of a
Streptomyces sp. The antifungal niromycin A and B, from S. albus, and
Streptimidone
(CXXII)
possibly fermicidin, from S. griseolus, belong in the same family.
Streptimidone (CXXII), an antibiotic from S. rimosus f. paromomycinus,
active against fungi and protozoa and weakly active against a few
bacteria, should be mentioned here since it comprises a glutarimide
moiety linked to a methylated 9-carbon unsaturated straight chain. It
has also the unexpected property of being herbicidal.
Cycloheximide, at the minimal growth-inhibitory level, completely
prevents protein and DNA synthesis in Aspergillus nidulans (281) and
Saccharomyces carlsbergensis; slightly higher concentrations also block
RNA synthesis (282).
According to Greig and collaborators (283), it inhibits fermentation
by Saccharomyces cerevisiae, an effect which is not observed on cell-free
extracts and is therefore attributed to an action at the cell surface.
MAURICE WELSCH
derivative of cycloheximide, antibiotic E-73, is an antitumor agent produced by S. albulus. It is highly toxic, but potentially useful derivatives
are being studied (280). Inactone is a biologically inactive 1,6-dehydrocycloheximide produced by S. griseus. The equally inactive actiphenol,
a closely related compound in which the cyclohexyl moiety is replaced
by an aromatic ring (CXXI), was isolated from the cultures of a
Streptomyces sp. The antifungal niromycin A and B, from S. albus, and
Streptimidone
(CXXII)
possibly fermicidin, from S. griseolus, belong in the same family.
Streptimidone (CXXII), an antibiotic from S. rimosus f. paromomycinus,
active against fungi and protozoa and weakly active against a few
bacteria, should be mentioned here since it comprises a glutarimide
moiety linked to a methylated 9-carbon unsaturated straight chain. It
has also the unexpected property of being herbicidal.
Cycloheximide, at the minimal growth-inhibitory level, completely
prevents protein and DNA synthesis in Aspergillus nidulans (281) and
Saccharomyces carlsbergensis; slightly higher concentrations also block
RNA synthesis (282).
According to Greig and collaborators (283), it inhibits fermentation
by Saccharomyces cerevisiae, an effect which is not observed on cell-free
extracts and is therefore attributed to an action at the cell surface.