The colourful chemistry of South African latrunculid sponges

Abstract

Marine sponges – in common with many other sessile marine invertebrates seemingly devoid of obvious physical forms of defence against predators, e.g. spines or shells – are the sources of a diverse array of organic chemical compounds known as marine natural products or secondary metabolites. Recent research has indicated that the production of natural products via cellular secondary metabolic pathways in some sponge species may not occur within the sponge cells themselves, but rather in microbial endosymbionts which inhabit the surface and interstitial spaces within the sponge tissue. Regardless of their biosynthetic origin, the bioactivity, e.g. toxicity, of many of these marine natural products may be utilised by sponges as chemical feeding deterrents to discourage predation or to provide a chemical anti-fouling competitive edge in the intense competition for living space amongst filter-feeders on space-limited benthic reefs. Paradoxically, a small number of sponge natural products have serendipitously shown potential as new pharmaceuticals, e.g. novel anti-cancer drugs. Marine biodiscovery (or bioprospecting) is the search for new pharmaceuticals from marine organisms. Exploration of the taxonomy, natural products chemistry and biomedicinal potential of the rich diversity of South African latrunculid sponges (family Latrunculiidae), at Rhodes University, the South African Department of Environmental Affairs and the University of the Western Cape has continued unabated for over a quarter of a century as part of a collaborative marine biodiscovery programme. A short review of this multidisciplinary latrunculid sponge research is presented here.

Chemistry, Chemotaxonomy and Biological Activity of the Latrunculid Sponges (Order Poecilosclerida, Family Latrunculiidae)

“…biannulata Topsent, 1892 [ 130 ] and S . insignis Topsent, 1890 [ 131 ], all from the Atlantic Ocean, specifically Floridian waters, and the Azores archipelago [ 25 , 132 ]. Sceptrella was compared to the monospecific Aleutian Islands genus, Latrunculava Kelly, Reiswig & Samaai, 2016, also with a second spicule form, the “sceptre”, in addition to the anisodiscorhabd first recorded from the Oamaru Diatomite (Eocene) of New Zealand [ 21 ].…”

“…Sceptrella was compared to the monospecific Aleutian Islands genus, Latrunculava Kelly, Reiswig & Samaai, 2016, also with a second spicule form, the “sceptre”, in addition to the anisodiscorhabd first recorded from the Oamaru Diatomite (Eocene) of New Zealand [ 21 ]. Species of Sceptrella are morphologically similar to Latrunculia and Strongylodesma species, with a cakey, dense and compressible texture, and a hemispherical or spherical body shape [ 132 ]. Sceptrella species are deep-sea organisms, having been recorded from a depth of 2460 m in some regions (e.g., the north coast of Norway) [ 25 ].…”

The 15th Frank Warren Organic Chemistry Conference

“…In 1949 the university became the University of Natal until 2004, when a merger formed the current University of KwaZulu‐Natal. It was here where Frank Warren began his work on pyrrolizidine alkaloids, and in the following years, his contribution to alkaloid chemistry, particularly those related to livestock losses, earned him local and international recognition, including a DSc from his alma mater . When Frank Warren retired from the University of Natal in 1965 to start a post as the first permanent Dean of Science at the University of Cape Town, he had supervised 62 of the 102 MSc and PhD students who had graduated from the department since his arrival .…”

“…The Frank Warren lecture is an exclusive invitation extended to an organic chemist currently practicing in South Africa, who has made an outstanding contribution to the field. The first Frank Warren lecture was given by Prof. Doug Rivett (Rhodes University), and has since become a list of the most distinguished organic chemists in the country.…”

Antimicrobial Potential and Phytochemical Screening of Clathria sp. 1 and Tedania (Tedania) stylonychaeta Sponge Crude Extracts Obtained from the South East Coast of South Africa

“…The first marine biodiscovery program was centred at a South African university. This program, a scuba collection of approximately a dozen marine sponges, was initiated by a Rhodes University ichthyologist team from a subtidal reef in the Tsitsikamma National Park, situated on the Southern Cape coast of South Africa during the spring of 1990 [ 6 ]. It was observed that sponge metabolites' primary biological activities were to kill or prevent the growth of microbial pathogens [ 7 ].…”