Pyrocystis lunula

Pyrocystis lunula (clone T37) can be grown under light-dark cycles as well as under continuous illumination at 20 2°C, in f/2 medium (Guillard and Ryther, 1962) with 0.5% soil extract instead of silicate (Guillard, 1974). The growth is somewhat slower and harvesting may be carried out about 40 days after inoculation, at a cell density of 15,000-20,000 cells/ml. 

Molecular characteristics of luciferase. A molecule of the luciferase of G. polyedra comprises three homologous domains (Li et al., 1997 Li and Hastings, 1998). The full-length luciferase (135 kDa) and each of the individual domains are most active at pH 6.3, and they show very little activity at pH 8.0. Morishita et al. (2002) prepared a recombinant Pyrocystis lunula luciferase consisting of mainly the third domain. This recombinant enzyme catalyzed the light emission of luciferin (luminescence A.max 474 nm) and the enzyme was active at pH 8.0. The recombinant enzyme of the third domain of G. polyedra luciferase was crystallized and its X-ray structure was determined (Schultz et al., 2005). A -barrel pocket putatively for substrate binding and catalysis was identified in the structure, and... 

The luciferins of all species of dinoflagellate are believed to be identical or very similar to each other (Hastings and Bode, 1961 Hamman and Seliger, 1972). However, the light yield of bioluminescence per cell differs significantly by the species, and certain species, such as Pyrocystis lunula, contain much more luciferin than other species, such as G. polyedra (Seliger et al., 1969 Swift and Meunier, 1976 Schmitter et al., 1976). Based on the luciferin content, P. lunula was chosen as the source of luciferin. 

Morishita, H., et al. (2002). Cloning and characterization of an active fragment of luciferase from a luminescent marine alga, Pyrocystis lunula. Photochem. Photobiol. 75 311-315. 

Seliger, H. H., Biggley, W. H., and Swift, E. (1969). Absolute values of photon emission from the marine dinoflagellates Pyrodinium bahamense, Gonyaulax polyedra and Pyrocystis lunula. Photochem. Photobiol. 10 227-232. 

Figure 3. Alignments in the region of the conserved histidines of the three domains of the seven luciferases. PI, Pyrocystis lunula Pn, P. noctiluca Pf, P. fusiformis At, Alexandrium tamarense Aa. A. affine Pr Protoceratium reticulatum.

Swift, E., and Meunier, V. (1976). Effects of light intensity on division rate, stimulable bioluminescence and cell size of the oceanic dinoflagellates Dissodinium lunula, Pyrocystis fusiformis and P. noctiluca. ]. Pbycol. 12 14-22. 

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