The unique and enigmatic spirochete symbiont of latrunculid sponges.

Bacterial symbionts are critical members of many marine sponge holobionts. Some sponge-associated bacterial lineages, such as Poribacteria, sponge-associated unclassified lineage (SAUL), and Tethybacterales, appear to have broad-host ranges and associate with a diversity of sponge species, while others are more species-specific, having adapted to the niche environment of their host. Host-associated spirochete symbionts that are numerically dominant have been documented in several invertebrates including termites, starfish, and corals.

A Quarter Century of Marine Biodiscovery in Algoa Bay, South Africa.

Algoa Bay, the largest crenulate bay on the southeastern coast of South Africa, is currently one of the most well-studied marine ecosystems in southern Africa. A plethora of endemic marine invertebrates inhabits the benthic reefs on the western edge of the Bay in close proximity to South Africa's sixth largest city. Over the past 25 years, South African marine natural products chemists, together with international collaborators from the US National Cancer Institute and other US institutions, have focused their attention on Algoa Bay's benthic marine invertebrates as a potential source of new anticancer compounds.

Managing human-mediated range shifts: understanding spatial, temporal and genetic variation in marine non-native species.

The use of molecular tools to manage natural resources is increasingly common. However, DNA-based methods are seldom used to understand the spatial and temporal dynamics of species' range shifts. This is important when managing range shifting species such as non-native species (NNS), which can have negative impacts on biotic communities.

Comparative Genomics Provides Insight into the Function of Broad-Host Range Sponge Symbionts.

The fossil record indicates that the earliest evidence of extant marine sponges (phylum Porifera) existed during the Cambrian explosion and that their symbiosis with microbes may have begun in their extinct ancestors during the Precambrian period. Many symbionts have adapted to their sponge host, where they perform specific, specialized functions. There are also widely distributed bacterial taxa such as , , and that are found in a broad range of invertebrate hosts.

New species in the sponge genus (Poecilosclerida, Latrunculiidae) from South Africa.

The genus Samaai & Kelly, 2002 is to date exclusively reported from South Africa. Three species are known from the southern coast: Samaai & Kelly, 2002, from the Garden Route National Park Tsitsikamma Marine Protected Area (MPA) and Algoa Bay; Samaai, Gibbons, Kelly and Davies-Coleman, 2003, collected from Cape Recife in St. Francis Bay, and Samaai, Gibbons, Kelly and Davies-Coleman, 2003, collected from a wreck site in a small bay west of Hout Bay on the west coast of South Africa.

Purification and biochemical characterisation of a putative sodium channel agonist secreted from the South African Knobbly sea anemone Bunodosoma capense.

Voltage gated ion channels have become a subject of investigation as possible pharmaceutical targets. Research has linked the activity of ion channels directly to anti-inflammatory pathways, energy homeostasis, cancer proliferation and painful diabetic neuropathy. Sea anemones secrete a diverse array of bioactive compounds including potassium and sodium channel toxins.

Molecular Networking Reveals Two Distinct Chemotypes in Pyrroloiminoquinone-Producing Tsitsikamma favus Sponges.

The temperate marine sponge, , produces pyrroloiminoquinone alkaloids with potential as anticancer drug leads. We profiled the secondary metabolite reservoir of sponges using HR-ESI-LC-MS/MS-based molecular networking analysis followed by preparative purification efforts to map the diversity of new and known pyrroloiminoquinones and related compounds in extracts of seven specimens. Molecular taxonomic identification confirmed all sponges as and five specimens (chemotype I) were found to produce mainly discorhabdins and tsitsikammamines.

A Place to Call Home: An Analysis of the Bacterial Communities in Two Tethya rubra Samaai and Gibbons 2005 Populations in Algoa Bay, South Africa.

Sponges are important sources of bioactive secondary metabolites. These compounds are frequently synthesized by bacterial symbionts, which may be recruited from the surrounding seawater or transferred to the sponge progeny by the parent. In this study, we investigated the bacterial communities associated with the sponge Samaai and Gibbons 2005.

Antibacterial Activities of Bacteria Isolated from the Marine Sponges Isodictya compressa and Higginsia bidentifera Collected from Algoa Bay, South Africa.

Due to the rise in multi-drug resistant pathogens and other diseases, there is renewed interest in marine sponge endosymbionts as a rich source of natural products (NPs). The South African marine environment is rich in marine biota that remains largely unexplored and may represent an important source for the discovery of novel NPs. We first investigated the bacterial diversity associated with five South African marine sponges, whose microbial populations had not previously been investigated, and select the two sponges (Isodictya compressa and Higginsia bidentifera) with highest species richness to culture bacteria.

Micromonohalimanes A and B: Antibacterial Halimane-Type Diterpenoids from a Marine Micromonospora Species.

Despite the fact that actinomycetes harbor the genetic potential to produce terpenes, terpenoid natural products tend to be a rare occurrence in fermentation broths. Here we report two new halimane-type diterpenoids, micromonohalimanes A (1) and B (2), that were isolated from a Micromonospora sp. cultivated from the marine ascidian Symplegma brakenhielmi.

Keeping it in the family: Coevolution of latrunculid sponges and their dominant bacterial symbionts.

The Latrunculiidae are a family of cold water sponges known for their production of bioactive pyrroloiminoquinone alkaloids. Previously it was shown that the bacterial community associated with a Tsitsikamma sponge species comprises unusual bacterial taxa and is dominated by a novel Betaproteobacterium. Here, we have characterized the bacterial communities associated with six latrunculid species representing three genera (Tsitsikamma, Cyclacanthia, and Latrunculia) as well as a Mycale species, collected from Algoa Bay on the South African southeast coast.

New polyhydroxylated sterols from Palythoa tuberculosa and their apoptotic activity in cancer cells.

The chemical study on the total extract of the zoanthid Palythoa tuberculosa, collected from the Red Sea, resulted in the isolation of seven polyhydroxylated sterols (1-7), six of which, palysterols A-F (2-7), are new. Their chemical structures were elucidated on the basis of extensive analysis of their 1-, 2D NMR and MS spectroscopic data. This is the first chemical investigation on the species collected from Red Sea.

Antimicrobial rubrolides from a South African species of Synoicum tunicate.

The CH₂Cl₂-MeOH extract of a South African tunicate described as the new Synoicum globosum Parker-Nance sp. nov. (Ascidiacea, Aplousobranchia) was subjected to ¹H NMR-guided fractionation.

Mandelalides A-D, cytotoxic macrolides from a new Lissoclinum species of South African tunicate.

Mandelalides A-D are variously glycosylated, unusual polyketide macrolides isolated from a new species of Lissoclinum ascidian collected from South Africa, Algoa Bay near Port Elizabeth and the surrounding Nelson Mandela Metropole. Their planar structures were elucidated on submilligram samples by comprehensive analysis of 1D and 2D NMR data, supported by mass spectrometry. The assignment of relative configuration was accomplished by consideration of homonuclear and heteronuclear coupling constants in tandem with ROESY data.