Drugs developed from natural products (NP’s - most commonly secondary metabolites) to combat widespread illnesses are common place; almost half of all anticancer drugs originate from NP’s. Microbial targets have contributed heavily to this stock of NP’s but traditionally only terrestrial microbes have been exploited extensively. NP discovery rates have been falling since the mid 70’s and now investigations into marine microbe natural products (MMNP’s) are being stepped up as the increase in antibiotic resistant pathogens, or ‘superbugs’, is causing growing concerns for public health.
MMNP’s are already undergoing clinical/pre-clinical trials, many providing promising treatments for many types of cancers but there is still a global deficit of new drug development from NP’s. The largely untapped reservoir of candidate marine microbes presents a large scale source of potential MMNP’s to combat persistent drug-resistant pathogens such as the Gram-positive methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant S. aureus (VRSA) to new emerging threats such as Gram-negative New Delhi metallo-beta-lactmase (NMD-1) bacteria.
Marine microbes are notoriously difficult to culture, so new and innovative culture methodologies are paving the way to larger scale exploitation and production of candidate MMNP’s. A recent review by Xiong et al., (2013) discusses this topic as it currently stands and outlines new pretreatment strategies for physical isolation of specific microbes along with refined culture mediums and alterations of ‘classical’ culture approaches. These advances have allowed the culture of previously uncultivated microbes e.g., the SAR11 marine bacterioplankton clade (Xiong et al. 2013: 702-704) but future investments in isolation and cultivation techniques will be vital to fully exploit the potential pool of microorganisms suitable for MMNP production. Xiong et al., (2013) also provides a valuable overview of innovative screening strategies being implemented to aid the discovery and development of MMNP’s. These valuable products have proven to be indispensable in past medical history so in order to generate and maintain an increasing NP discovery curve, efforts such as those outlined in the review by Xiong et al. (2013) will be critical to the future of NP’s and MMNP’s in industrial scale applications.
Xiong, Z.Q., Wang J.F., Hao Y.Y. and Wang Y. (2013). Recent Advances in the Discovery and Development of Marine Microbial Natural Products. Marine Drugs 11, 700-717.