The Luminous Flying Squid Symplectoteuthis luminosa Suji-ika

3 The luminous Flying Squid Symplectoteuthis luminosa (Suji-ika) 

Extraction and partial purification of photoprotein. The solubility and general luminescence characteristics of the S. luminosa photoprotein are similar to those reported for the S. oualaniensis photoprotein the protein is soluble in buffer solutions containing 0.6-1.0 M salt but not in solutions containing 0.1-0.2 M salt, and the luminescence is pH-dependent. In the extraction of S. oualaniensis, 

Assay of photoprotein. The activity of the photoprotein was measured in 1ml of 20 mM Tris-HCl buffer, pH 8.0, containing 0.6 M NaCl at room temperature. The intensity and total amount of light emitted were recorded. The luminescence intensity is markedly intensified by adding 5 il of catalase solution (crystalline bovine liver catalase 1.5 mg/ml) and 10 pi of 3% H2O2. 

Pretreatment of Sample and Treatment Time (min) Reagents Added and Reaction Time (min) Initial Intensity (LU/s)b Total Light Emitted (LU)b 

In vivo luminescence of the Symplectoteutbis species. The live specimens of both S. oualaniensis and S. luminosa emit bright flashes 

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