Stereostructure and Biological Activity of 42-Hydroxy-palytoxin: A New Palytoxin Analogue from Hawaiian Palythoa Subspecies

Abstract

This paper reports on the analysis of the toxin content from Palythoa tuberculosa and Palythoa toxica samples collected off of the Hawaiian coast. Our work, based on in-depth high-resolution liquid chromatography-mass spectrometry analysis along with extensive NMR study, led us to structurally characterize 42-hydroxy-palytoxin, a new palytoxin congener. This toxin and palytoxin itself appeared to be the major components of toxic extract from a P. tuberculosa sample, while 42-hydroxy-palytoxin was proven by far to be the main palytoxin derivative in P. toxica. Functional studies on this new palytoxin-like compound suggest that the new palytoxin analogue and palytoxin itself present similar biological activities.

High Resolution LC-MSn Fragmentation Pattern of Palytoxin as Template to Gain New Insights into Ovatoxin-a Structure. The Key Role of Calcium in MS Behavior of Palytoxins

“…Summing-up, on the basis of the above results, ovatoxina, compared with palytoxin, (1) lacks three hydroxyl groups, one at C-17, one at C-44 or C-45, and one in the region C-53 to C-78, respectively; (2) presents an additional hydroxyl group at C-42, similarly to 42-hydroxy palytoxin and ostreocin-D [6,7]; (3) presents the same structural features as palytoxin in the regions ranging from the A-side terminal to C-16, from C-18 to C-41, from C-46 to C-52, and from C-79 to the B-side terminal.…”

“…A number of palytoxin analogues have been so far isolated either from soft corals (Palythoa genus) or dinoflagellates (Ostreopsis spp. ): homo, bishomo-, neo-, and 73-deoxy-palytoxin [5], ostreocin-D (namely 42-hydroxy-3,26-didemethyl-19,44-dideoxypalytoxin) [6], and 42-hydroxy-palytoxin [7]. Structure elucidation of these compounds was carried out by extensive NMR analyses and in most cases through the use of degradation/derivatization reactions [1,5,8].…”

Sanitary problems related to the presence of Ostreopsis spp. in the Mediterranean Sea: a multidisciplinary scientific approach

“…As mentioned above, PLTX is known to impair the activity of the Na + /K + pump, with dramatic consequences on cellular ionic homeostasis [36][37][38][39]50]. As well as high toxicity, quite common to all the cells models tested so far [74], PLTXs triggered an uncontrolled intracellular calcium ([Ca 2+ ] i ) increase [72,73] and morphological alterations [73]. These events seemed to be strictly related to the development of the toxic insult [73].…”

“…The toxicity was initially evaluated, within 24 h after the administration, on the parent compound PLTX and it was found to be strictly dose-related [70]. Later, the study was repeated on 42-hydroxy-PLTX [71], chemically characterized in 2009 [72] (Figure 2). Similar in structure, PLTX and 42-hydroxy-PLTX also resulted in similar toxicity and symptoms.…”

Warm Seawater Microalgae: Growth and Toxic Profile of Ostreopsis Spp. from European Coasts

“…The PLTX-group of toxins includes complex polyhydroxylated compounds with a lipophilic and a hydrophilic area. Different molecules related with the PLYX structure ( Figure 1) have been described: palytoxin-b, homopalytoxin, bishomopalytoxin, neopalytoxin, deoxypalytoxin, 42-hydroxypalytoxin, ostreocin-d, ovatoxin-a, -b,-c,-d, -e and -f and mascarenotoxin-a, -b and -c. However only the chemical structures of PLTX, ostreocin-d, ovatoxin-a and 42-hydroxypalytoxin have been characterized [4][5][6][7][8][9][10][11]. PLTX is a large molecule, with a molecular weight of 2659-2680 daltons depending on the origin [12,13].…”