A compound extracted from a deep-water marine sponge could end up helping develop antibacterial solutions against a drug-resistant “super bacteria.”
The sponge, discovered near the Bahamas, has shown promise in fighting methicillin-resistant Staphylococcus aureus (MRSA), which is resistant to all beta-lactam antibiotics and can be fatal.
Researchers at Florida Atlantic University’s Harbor Branch Oceanographic Institute were able to demonstrate the isolation, structure elucidation and biological activity of the new indole alkaloid isolated dubbed dragmacidin G from a marine sponge.
Amy Wright, Ph.D., lead author and a research professor at FAU’s Harbor Branch who directs the Institute’s drug discovery program, explained that the compound has a broad spectrum of biological activity including inhibition of MRSA as well as a panel of pancreatic cancer cell lines.
“Sponges of the genus Spongosorites, have been a source of a number of biologically active bis-indole alkaloids that are reported to have a variety of activities including antibacterial, antiviral, antifungal, antiplasmodial, cytotoxic as well as anti-inflammatory activities,” Wright said in a statement. “We found substantial antibacterial activity for dragmacidin G.
“It is greater than 10-fold more potent than other members of the bis-indole alkaloids while retaining selectivity towards bacterial over mammalian cells.”
According to the study, the deep-water sponge is of the genus Spongosorites, which has been the source of a number of biologically active bis-indole alkaloids, including the topsentins, nortopsentins, hamacanthins and dragmacidins.
The researchers screened the compound in a number of assays, including growth inhibition of MRSA, while also testing the growth inhibition of the causative agent for tuberculosis and the parasite Plasmodium falciparum, one of the causes of malaria in humans.
The highly enriched fraction containing the compound showed activity in all three assays and was then purified to obtain pure dragmacidin G, which enabled its structure elucidation and biological testing.
According to the Centers for Disease Control and Prevention, more than 80,000 invasive MRSA infections and 11,285 related deaths occur every year.
The discovery is part of an ongoing effort by scientists at FAU’s Harbor Branch to collect unusual marine organisms to aid in drug discovery.
The results of the recent study are considered preliminary.