The discovery of new antibiotics reached its peak during the golden era of antibiotics in the mid 20th century and continued to thrive until the 1980s. However, after more than 50 years of fruitful exploration and exploitation of microbial natural products the discovery rate of new antibiotics has dropped drastically...
Pactamycin, a potent antitumor antibiotic produced by the soil bacterium Streptomycespactum, is a structurally unique aminocyclopentitol-containing natural product. Itconsists of a highly functionalized cyclopentitol core unit, two aromatic rings [3-aminoacetophenone (3AAP) and 6-methylsalicylic acid (6MSA)], and a 1,1-dimethylurea moiety. Despite its potent biological activity, the development of thisantibiotic was hampered...
Among the myriad of naturally occurring bioactive compounds are the aminocyclopentitol-containing natural products that represent a family of sugar-derived microbial secondary metabolites, such as the antibiotics pactamycin, allosamidin, and trehazolin. Pactamycin, a structurally unique aminocyclitol antibiotic isolated from Streptomyces pactum, consists of a 5-membered ring aminocyclitol (cyclopentitol) unit, two aromatic...
A modified agar overlay technique for the preliminary screening
of antibiotic producing Streptomyces spp. has been developed and
compared to the routinely used shake flask method and the
unmodified agar overlay technique. The percentage of isolates
exhibiting antimicrobial activities was found to be greater in the
modified overlay technique.
Three...