Scientists have found that a marine sulfur-loving microbe discovered recently near Chilean coastal fault line can produce a new 18-membered macrolide antibiotic, macplocimine A.

“The search for new drugs takes many forms and routes, but one that often has success is the search for microbes,” explained Dr Nathan Magarvey from the Michael G. DeGroote Institute for Infectious Disease Research, who is a senior author of the study published in the Journal of Antibiotics.

“The fascination of finding drugs from natural sources has long been guided by serendipity alone, but now researchers are defining genomic and metabolomic patterns that illustrate where new drugs may be found and how these drugs are made and change.”

Dr Magarvey with colleagues isolated a previously unknown species of sulfur-oxidizing Thioploca bacteria from the benthic microbial ecosystem on the continental shelf off the coast of Chile.

They then determined the potential of this bacterium to generate significant natural products. A small molecule, named macplocimine A, was isolated and structurally defined.

According to the team, macplocimine A is a pale yellow solid, with the molecular formula C 27 H 36 O 9 N 2 .

Dr Magarvey’s team also unveiled principles of how microbes are generating natural bioactive small molecules and creating new ones. Using a combination of genetic and chemical approaches, the new findings ultimately lead to a better appreciation of how good nature is at making diverse drugs.

“In other words, we captured and honed-in on some previously unexplored terrestrial and marine bugs and uncloaked the process by which they make drugs scaffolds,” Dr Magarvey said.

“This is another example of the power of the microbe to create fascinating chemicals that we can exploit to treat human disease,” he concluded.

______

Bibliographic information: Xiang Li et al. 2013. Macplocimine A, a new 18-membered macrolide isolated from the filamentous sulfur bacteria Thioploca sp. The Journal of Antibiotics 66, pp. 443–446; doi: 10.1038/ja.2013.52