Unveiling the Chemical Diversity of the Deep-Sea Sponge Characella pachastrelloides

Abstract

Sponges are at the forefront of marine natural product research. In the deep sea, extreme conditions have driven secondary metabolite pathway evolution such that we might expect deep-sea sponges to yield a broad range of unique natural products. Here, we investigate the chemodiversity of a deep-sea tetractinellid sponge, Characella pachastrelloides, collected from ~800 m depth in Irish waters. First, we analyzed the MS/MS data obtained from fractions of this sponge on the GNPS public online platform to guide our exploration of its chemodiversity. Novel glycolipopeptides named characellides were previously isolated from the sponge and herein cyanocobalamin, a manufactured form of vitamin B12, not previously found in nature, was isolated in a large amount. We also identified several poecillastrins from the molecular network, a class of polyketide known to exhibit cytotoxicity. Light sensitivity prevented the isolation and characterization of these polyketides, but their presence was confirmed by characteristic NMR and MS signals. Finally, we isolated the new betaine 6-methylhercynine, which contains a unique methylation at C-2 of the imidazole ring. This compound showed potent cytotoxicity towards against HeLa (cervical cancer) cells.

Metabolomic comparison usingStreptomycesspp. as a factory of secondary metabolites

“…Aplysiatoxins from marine cyanobacteria were described with potential new analogs. Another study of MS/MS data obtained from fractions on the public GNPS platform suc-ceeded in dereplicating new glycolipopeptides called characellides, cyanocobalamin and poecillastrins of a deep-sea tetractinellid sponge, Characella pachastrelloides [24,25]. Initial chemical investigation of the extract obtained from Streptomyces spp.…”

Marine natural products

“…In addition, an unusual and weakly cytotoxic amino acid, 6-methylhercynine 968 was isolated during the same study. 382 …”

“…In addition, an unusual and weakly cytotoxic amino acid, 6-methylhercynine 968 was isolated during the same study. 382 Sponge-derived alkaloids include haliclorensin D 969 and two haliclonacyclamines 970 and 971 from a Neopetrosia and a Callyspongia, respectively, 383,384 while related zamamiphidin alkaloids 972 and 973 were isolated from a Japanese Amphimedon sponge. 385 An N-oxide congener of manzamine A 974 has been isolated from Neopetrosia proxima, 386 while N. chaliniformis yielded four indole-C-mannopyranosides, neopetrosins A-D 975-978, most of which have weak hepatoprotective activity.…”

Metabolomic Comparison Using Streptomyces spp as a Factory of Secondary Metabolites

“…Aplysiatoxins from marine cyanobacteria were described with potential new analogs. Another study of MS/MS data obtained from fractions on the public GNPS platform succeeded in dereplicating new glycolipopeptides called characellides, cyanocobalamin and poecillastrins of a deep-sea tetractinellid sponge, Characella pachastrelloides [24,25]. Initial chemical investigation of the extract obtained from Streptomyces spp.…”