Ophiopsila californica

Fig. 10.1.3 Fluorescence excitation and emission spectra (solid lines) and H2O2-triggered luminescence spectrum (dashed line) of Ophiopsila photoprotein (Shimomura, 1986b, revised). The dotted line indicates the in vivo bioluminescence spectrum of Ophiopsila californica plotted from the data reported by Brehm and Morin (1977).

This luminous brittle star has been briefly studied recently (Mallefet and Shimomura, 2004, unpublished).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. 

Brehm, P., and Morin, J. G. (1977). Localization and characterization of luminescent cells in Ophiopsila californica and Amphipholis squamata (Echinodermata Ophiuroidea). Biol. Bull. 152 12-25. 

Shimomura, O. (1986b). Bioluminescence of the brittle star Ophiopsila californica. Photochem. Photobiol. 44 671-674. 

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