Ptychodera flava

Dure and Cormier (1961) demonstrated a luciferin-luciferase reaction for the first time in the extracts of the acorn worm Balanoglossus biminiensis, and also discovered that the luminescence reaction is stimulated by H2O2, of which the details are described below. Recently, Kanakubo and Isobe (2005) reported the chemical structure of a probable luciferin of another acorn worm Ptychodera flava. 

Fig. 10.4.3 Left panel Bioluminescence spectrum of the acorn worm Ptychodera flava stimulated with H2O2. Right panel (a) The spectrum of the chemiluminescence emitted when 70% dioxane containing 1.7% H2C>2 (5 ml) was added to a mixture of a solution of 2,3,5,6-tetrabromohydroquinone (TBHQ) in ethyl acetate (2.5 ml), 50 mM glycine buffer (pH 12.0 2.5 ml), and riboflavin (b) when riboflavin was omitted and (c) when TBHQ was omitted. Dioxane was included to solubilize the ethyl acetate solution containing TBHQ. From Kanakubo et al., 2005, with permission from Elsevier.

Kanakubo, A., and Isobe, M. (2005). Isolation of brominated quinones showing chemiluminescence activity from luminous acorn worm, Ptychodera flava. Bioorg. Med. Chem. 13 2741-2747. 

During the last thirty-five years, a variety of biologically active substances bearing a novel carbon skeleton have been found in marine organisms. Of them, a number of highly brominated diphenyl ethers with antibacterial and antitumor activities were isolated from Dysidea herbaceae and Ptychodera flava laysanica. These metabolites are regarded as a self-defensive substance. In order to synthesize these metabolites, electrochemical oxidation of bromophenols has been carried out °. Some typical examples are shown here. 

CHEMICAL STUDIES ON BIOLUMINESCENCE OF ACORN WORM, PTYCHODERA FLAVA ISOLATION AND CHARACTERIZATION OF LUMINOUS SUBSTANCES... 

Ptychodera flava (P. flava), smaller acom worm, was found in Kattore bay, Kohama Island, Okinawa by Higa. " Only the fact that P. flava emitted light by H2O2 was known. For the understanding of the molecular mechanism of bioluminescence, we determined the structures of luminous compounds and a possible light emitter. 

Akira Kanakubo (Laboratory of Organic Chemistry, School of Bioagricultural Sciences, Nagoya Univeristy, Nagoya, Japan) Chemical studies on bioluminescence of Acorn worm, Ptychodera flava Isolation and characterization of luminous substances... 

Higa, T. and Scheuer, P.J., 1977. Constituents of the hemichordate Ptychodera flava laysanica. In D.J. Faulkner and W.H. Fenical (Editors), Marine Natural Products Chemistry. Plenum Press, London, pp. 34—43. 

Peterson, K.J., Cameron, R.A., Tagawa, K., Satoh, N., and Davidson, E.H., A comparative molecular approach to mesodermal patterning in basal deuterostomes the expression pattern of Brachyury in the enteropneust hemichordate Ptychodera flava. Development, 126, 85-95, 1999. 

The bioltiminescence of some enteropneusts is due to a series of bromohydroquinones and bromoquinones which have been isolated from Ptychodera flava of Japanese origin. The major bioluminescent substance is 2,3,5,6-tetrabromohydroquinone (TetraBHQ), which emits radiation at 528 nm in the presence of riboflavin (Kanakubo and Isobe, 2005). 

Bioluminescent bromohydroquinones and quinones from Ptychodera flava. 

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