Sea pens

Anthozoa. Anthozoans are plant-shaped polyps, either solitary or colonial, completely lacking the medusoid stage. They are found along coastal waters and include the luminescent genera Renilla (the sea pansies), Cavernularia (the sea cactuses), and Ptilosarcus and Pennatula (the sea pens). Bioluminescent anthozoans emit light by a luciferin-luciferase reaction that involves coelenterazine as the... 

Fig. 4.6.1 Two examples of luminous anthozoans the sea pansy Renilla reniformis (left) and the sea pen Ptilosarcus gmneyi (right).

Soon after the hypothetical structure was published, coelenterazine was isolated as an actual substance from the liver of the luminous squid Watasenia scintillans, and it was chemically synthesized (Inoue et al., 1975). The availability of synthetic coelenterazine led to the important discovery that the treatment of the luminescence product of aequorin with coelenterazine results in the regeneration of active aequorin (Shimomura and Johnson, 1975c), which consequently confirmed the presence of a coelenterazine moiety in the aequorin molecule. During the same period, it became increasingly evident that coelenterazine is involved as a luciferin in various bioluminescent organisms, such as the sea cactus Cavernularia, the sea pen Ptilosarcus, and the sea pansy Renilla (Shimomura and Johnson, 1975b). 

This luminous brittle star has been briefly studied recently (Mallefet and Shimomura, 2004, unpublished). The animal contained a high level of coelenterazine luciferase activity (4 x 1012 photons s-1g 1), which is comparable to those in the luminous antho-zoans such as the sea pansy Renilla and sea pen Ptilosarcus (Shimomura and Johnson, 1979b). There is no evidence for the presence of a photoprotein in this brittle star. Thus, the luminescence system of Amphiura filiformis is considered to be a coelenterazine-luciferase system, differing from that of Ophiopsila californica. The luciferase has a molecular weight of 23,000 on the basis of gel filtration on Superdex 200 Prep, and catalyzes the luminescence reaction of coelenterazine in the presence of oxygen the light emission (A.max 475 nm) is optimum at pH 7.2. 

Peniagone, 301, 337 Pennatula (Sea pens), 91, 334 Peridinium, 333 Periphylla, 179, 334 Peripbylla bioluminescence, 140-147 inhibitors, 144... 

The sub-phyllum Anthozoa (6,500 species) contains the classes Alcyonaria (soft corals, sea fans, sea pens, sea pansies), Zoantharia (sea anemones and true corals), and Ceriantipatharia. The Scleroactinia (Madreporaria-true or stony corals) build the massive coral reefs and atolls which occur in tropical waters. According to Hashimoto (75), toxicity to humans is mainly found in the fire or stinging corals (Millepora sp.) and, to a lesser extent, in the stony corals (Goniopora sp.). 

Soft parts Reared in sea pens with tributyltin-coated netting for 3 weeks Total tin ... 

Short, J.W. and F.P. Thrower. 1986. Accumulation of butyltins in muscle tissue of chinook salmon reared in sea pens treated with tri- -butyltin. Mar. Pollut. Bull. 17 542-545. 

Some time ago, we initiated a study of the coelenterate Briareum polvanthes to ascertain whether there was a chemotaxonomic basis for the species distinction between the Briareum found in Bermuda and the more common fl,. asbestinum found throughout the Caribbean. We have found a series of new diterpenes, 9-13, with the briaran skeleton (17.22.2T). It has been implied (24.2 5) that this class of compounds serves as a chemical defense against predation in the soft corals and sea pens which produce them, but this has not yet been demonstrated by bioassay. 

Ptilosarcone (157) is a toxin which was isolated from the sea pen, Ptilosarcus gurneyi. Its structure was assigned by comparison of its n.m.r. spectrum with that of... 

Fig. 3.9 Pteroeides sp., a sea pen from Flores, Indonesia, that contains the novel diterpenes 586 and 587 (Photo J. Tanaka)...

Next, Schmitz and colleagues116 reported the isolation and characterization of malayenolides AD, series of novel diterpenes from the Indonesian sea pen Veretillum malayense. The structures were elucidated using proton-detected 2D-NMR methods in conjunction with the use of 3 mm NMR probe technology. The structure of malayenolide-A (53) is shown. 

Unusual 20-epicholanic acid derivatives (68,69) were isolated from the sea pen, Ptilosarcus gumeyi [76]. A characteristic property of these compounds is the shorter... 

Sidelnikov V, Partrushev Y Short JW and Thrower FP (1986) Accumulation of butyltin in muscle tissue of Chinook salmon reared in sea pens treated with tri-n-butyltin. Ocean s 86 Conference Proceedings Organotin Symposium 4 1177— 1181. 

Marine organisms have again continued to provide some-very unusual diterpenoids. The sea-pen, Stylatula sp., was the source of the compounds (72) and (73). X-Ray analysis has shown that cleomeolide, from Cleome icosandra, has the structure (74). A further diterpenoid related to eunicellin, ophirin (75), has been obtained from a Muricella sp. A full paper on the ether dictyoxide (76) has appeared. ... 

Several 5a,8a-epidioxy sterols (3-12, 14-16, 454) have been isolated from the common pillar coral, Dendrogyra cylindrus (67) and (3-5, 6 and/or 7, 8-10) from the sea pen, Virgularia sp. 386). The probable biological significance of these epidioxy sterols has been discussed by Gunatilaka et al. 67) with special reference to sterol biosynthesis. A soft coral of the genus Sinularia contained a series of sterols... 

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