Aplysinella rhax

Four minor metabolites, psammaplins B-D (503-505) and presammaplin A (506) were isolated from Psammaplysilla purpurea, in addition to psammaplin A (500). Psammaplin B (503) is a thiocyanate bromotyrosine derivative, while psammaplin C (502) is a sulfanamide. Psammaplin D (505) displayed antimicrobial activity and mild tyrosine kinase inhibition [429]. The psammaplins Ai (507) and A2 (508) and aplysinellins A (509) and B (510) were isolated from Aplysinella rhax from both Pohnpei and Palau. These compounds inhibit famesyl protein transferase and leucine aminopeptidase [430]. Another sample of A. rhax from the Great Barrier Reef, Australia contained psammaplin A 11 -sulfate (511) and bisaprasin ll -sulfate (512), both of which inhibited [3H]-l,3-dipropyl-8-cyclopentylxanthine binding to rat brain adenosine Ai receptors [431]. 

Pham NB, Butler MS, Quinn RJ (2000) Isolation of Psammaplin A 11 -Sulfate and Bisaprasin 11 -Sulfate from the Marine Sponge Aplysinella rhax. J Nat Prod 63 393... 

Tabudravu JN, Eijsink VGH, Gooday GW, Jaspars M, Komander D, Legg M, Synstad B, van Aalten DMF (2002) Psammaplin A, a Chitinase Inhibitor Isolated from the Fijian Marine Sponge Aplysinella rhax. Bioorg Med Chem 10 1123... 

A second example of an activated chemical defense concerns the Indo Pacific sponge Aplysinella rhax, in which tissue damage results in the rapid enzymatic transformation of psammaplin A sulfate 63 into psammaplin A 64 exposure of 63 to tissue from other sponges does not result in any conversion. Compound 63 deters feeding by reef fish, but when offered a choice between psammaplin A and its sulfate, both foods were avoided. In aquarium assays with C. solandri, extracts of damaged tissue were more deterrent than extracts from intact tissue, but both treatments were less palatable than control foods. In choice experiments, C. solandri preferred food treated with 63 over 64.104... 

Thorectopsamma xana Poecillastra sp. / Jaspis sp. association Aplysinella rhax Pseudoceratina purpurea... 

Borbone, N., De Marino, S., lorizzi, M., Zollo, F., Debitus, C., lanaro, A., and Pisano, B. (2001) New glycosphingolipids from the marine sponge Aplysinella rhax and their potential as nitric oxide release inhibitors. Eur. J. Org. Chem., 4651-4656. 

Pham, N.B., Butler, M.S., and Quinn, R.J. (2000) Isolation of psammaplin A 112-sulfate and bisaprasin ll-suFate from the marine sponge Aplysinella rhax. J. Nat. Prod., 63, 393-395. 

Hada, N., Nakashima, T., Shrestha, S.P., Masui, R., Narukawa, Y, Tani, K., and Takeda, T. (2007) Synthesis and biological activities of glycosphingolipid analogues from marine sponge Aplysinella rhax. Bioorg. Med. Chem. Lett., 17, 5912—5915. 

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