Biotechnology and Bioinformatics (1+1)

5.1.6. Marine sponges

The wider biosynthetic capability of sponges could be attributed to their biological association with other symbionts.

• About 38% of the sponge body comprises of microorganisms.
• A wide variety of secondary metabolites were isolated from sponges and these have been associated with antibacterial, antimicrobial, antiviral, antifouling, HIV-protease inhibitory, HIV reverse transcriptase inhibitory, immuno-suppressent and cytotoxic activities.
• In addition to potential anticancer applications, the bioactive compounds of sponges have a myriad of activities ranging from antibiotic activity including anticoagulant, antithrombin, anti-inflammatory, as well as imunomodulatory activities.
• Chemicals found in sponges may be used to treat yeast and fungi.
• The fact that the psammaplins have been isolated from a diversity of sponge “sources” and that brominated aromatic amino acid derivatives are common in marine bacteria suggests that these metabolites may actually derive from biosynthetic pathways of microorganisms living in association with sponges.

Presence of specific symbiont morphologies of bacteria within specific sponges has been reported. These specific bacteria, which live symbiotically with sponges, passed through their feeding chambers without being digested. This suggested some sort of encapsulation or recognition process.

• In the demosponge, Halichondria panicea, an association with the microbe Pseudomonas insolita was suggested to be lectin-based. In the case of halichondrin, the exciting anticancer potential of this “sponge” metabolite has fueled an innovative chemical synthesis approach.
• Marine animals have yielded cardiovascular-active substances, and these include histamine and N-methylated histamines of sponges, viz. Verongia fistularis; asystolic nucleosides from the sponge, Dasychalina cyathina; and the nucleoside, spongosine, isolated from Cryptotethya crypta.