Hydroids

First, mention should be made of the metathetical reaction, replacing an anion of a pyrylium salt by another-, when the solubility of the latter salt is lower than that of the former, the conversion is easy. In the opposite case, one has to find a solvent in which the solubilities are reversed (perchlorates are less soluble in water than chloroferrates or iodides, but in concentrated hydrochloric or hydroidic acids, respectively, the situation is reversed For preparing chlorides which are usually readily soluble salts, one can treat the less soluble chloroferrates with hydrogen sulfide or hydroxylamine. Another method is to obtain the pseudo base in an organic solvent and to treat it with an anhydrous acid. 

Bondar, V. S., Vysotskii, E. S., Gamalei, I. A., and Kaulin, A. B. (1991). Isolation, properties, and application of calcium activated photoprotein from the hydroid polyp Obelia longissima. Tsitologiya 33 50-59. 

Campbell, A. K. (1974). Extraction, partial purification and properties of obelin, the calcium-activated luminescent protein from the hydroid Obelia geniculata. Biochem. J. 143 411—418. 

Hastings, J. W., and Morin, J. G. (1968). Calcium activated bioluminescent protein from ctenophores (Mnemiopsis) and colonial hydroids (Obelia). Biol. Bull. 135 422. 

Illarionov, B. A., et al. (1992). Cloning and expression of cDNA coding for the calcium-activated photoprotein obelin from the hydroid polyp Obelia longissima. Dokl. Akad. Nauk SSSR 326 911-913. 

Letunov, V. N., and Vysotski, E. S. (1988). Bioluminescence activity and content of calcium-dependent photoprotein in Obelia longissima (Pallas) hydroid colonies. Zh. Obshch. Biol. 49 381-387. 

Markova, S. V., et al. (2002). Obelin from the bioluminescent marine hydroid Obelia geniculata cloning, expression, and comparison of some properties with those of other Ca2+-regulated photoproteins. Biochemistry 41 2227-2236. 

Vysotski, E. S., etal. (1999). Preparation and preliminary study of crystals of the recombinant calcium-regulated photoprotein obelin from the biolu-minescent hydroid Obelia longissima. Acta Cryst. D55 1965-1966. 

Marine fouling, namely, the attachment of such marine organisms as barnacles, algae, tubeworms, hydroids, and sponges to a surface im-... 

Marine hydroids are commonly defended from predation by nematocysts that are capable of penetrating the tissue of predators, and injecting proteinaceous venom. However, lipophilic secondary metabolites also protect many hydroid species. The hydroid Tridentata marginata is chemically defended by tridentatols A-D (85-88), of which tridentatol A (85) is a potent deterrent to fish predation (Scheme 22) [160]. 

Scheme 22 Wound-activated tridentatol-release by the hydroid Tridentata marginata...

Hydroid, Campanularia flexuosa 1.0 100% growth inhibition in 11 days 3... 

Specimens from Radio Is., North Carolina (not a true tropical system, see text for details) Pachydictyol A inhibits the sea urchin A. punctulata and dictyol A acetate inhibits this sea urchin species, the amphipod Ampithoe longimana, and the pinlish /,. rhomboides (Bolser and Hay 1996). Pachydictyol A, dictyol B acetate, dictyol E, and dictyodial, also obtained from the same specimens, cause larval mortality, abnormal development, and reduced growth in bryozoans and hydroid species (Schmitt et al. 1998)... 

Harder T, Dobretsov S, Qian PY (2004) Waterborne polar macromolecules act as algal antifou-lants in the seaweed Ulva reticulata. Mar Ecol Prog Ser 274 133-141 Harder T, Qian PY (2000) Waterborne compounds from the green seaweed Ulva reticulata as inhibitive cues for larval attachment and metamorphosis in the polychaete Hydroides elegans. Biofouling 16 205-214... 

The marine hydroid Tridentata marginata contained the aromatic alkaloids tridentatols A-C (186-188). Tridentatol A (186) inhibited feeding by the planehead filefish. The structure of tridentatol C (188) was elucidated by a single crystal X-ray diffraction study [179]. 

Volutamides A-E (143-147), halogenated alkaloids of amino acid origin, have been isolated from the Atlantic bryozoan Amathia convoluta. Several of the volutamides deter feeding by potential predators and are toxic toward larvae of the co-occurring hydroid Eudendrium carneum, suggesting that these metabolites form the basis of an effective chemical defense. [114]. 

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