title: Endogenous regulation of the functional duality of pahutoxin, a marine trunkfish surfactant.
abstract: Pahutoxin (PHN) is a long chain detergent-like quaternary ammonium cationic substance derived from defensive skin secretions of trunkfish. A recent study has revealed that PHN's ichthyotoxicity and its phospholipid membrane disruption effect are produced by two separate mechanisms, which presumably represent two separate physicochemical domains in the PHN molecule [Kalmanzon, E., Rahamim, Y., Barenholz, Y., Carmeli, S., Zlotkin, E., 2003. Receptor-mediated toxicity of pahutoxin, a marine trunkfish surfactant. Toxicon 42, 63-71]. Here we report on the occurrence of a natural endogenous mechanism, which regulates the above PHN's functional duality. The regulation is performed by the aid of two separates constituents of the trunkfish secretion, which either selectively amplify PHN's ichthyotoxicity (factor I) or suppress its phospholipids permeabilization effect (factor II). The ecological significance of such endogenous regulation is discussed.
authors.affiliation: Department of Animal and Cell Biology, Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem 91904, Israel.
authors.forename: Eliahu
authors.initials: E
authors.lastname: Kalmanzon
authors.forename: Yocheved
authors.initials: Y
authors.lastname: Rahamim
authors.forename: Shmuel
authors.initials: S
authors.lastname: Carmeli
authors.forename: Yechezkel
authors.initials: Y
authors.lastname: Barenholz
authors.forename: Eliahu
authors.initials: E
authors.lastname: Zlotkin
mesh_terms: D000818:Animals; D002794:Choline / Q000031:analogs & derivatives* / Q000737:chemistry / Q000378:metabolism* / Q000633:toxicity*; D008081:Liposomes / Q000737:chemistry; D008387:Marine Toxins / Q000737:chemistry / Q000378:metabolism* / Q000633:toxicity*; D010539:Permeability / Q000187:drug effects; D021541:Sea Bream; D012867:Skin / Q000378:metabolism; D013501:Surface-Active Agents / Q000737:chemistry / Q000378:metabolism / Q000633:toxicity*; D023721:Tetraodontiformes / Q000378:metabolism*; D013997:Time Factors
chemical_list: D008081:Liposomes; D008387:Marine Toxins; D013501:Surface-Active Agents; C052962:pahutoxin; D002794:Choline