Actinomycetes are well known soil bacteria that were once believed to occur in the ocean only when washed in from land. Today, it is clear that unique populations of marine actinomycetes reside in ocean sediments and that these bacteria are fundamentally different from those on land. Although terrestrial actinomycetes have been the source of many of today's more than 120 drugs, marine actinomycetes have only recently been incorporated into the discovery process. These bacteria are now proving to be a particularly rich source of unique natural products, many of which display potent biological activities.

An issued patent includes:

• Broad claim for cyclic polyene-polyols, which are strengthened by exact specification of six compositions of matter.
• Broad claims for methods of use as antitumor and antibiotic drugs.

• Novel class of molecules may provide antibiotics against MDR-bacteria in humans as well as domestic and farm animals.
• Compositions may provide new drugs for single or combination therapy versus various cancers.

Researchers at the Scripps Institution of Oceanography have discovered a new group of marine actinomycetes that have tentatively been called MAR2. These bacteria produce unique, polyketide-derived macrolides including a series of compounds called marinomycins A-D, which were discovered from the MAR2 strain CNQ-140 (Kwon et al., 2006). These compounds possess potent antibiotic and antitumor properties.