title: Effects of Hemagglutination Activity in the Serum of a Deep-Sea Vent Endemic Crab, Shinkaia Crosnieri, on Non-Symbiotic and Symbiotic Bacteria.
abstract: In deep-sea hydrothermal environments, most invertebrates associate with dense populations of symbiotic microorganisms in order to obtain nutrition. The molecular interactions between deep-sea animals and environmental microbes, including their symbionts, have not yet been elucidated in detail. Hemagglutinins/lectins, which are carbohydrate-binding proteins, have recently been reported to play important roles in a wide array of biological processes, including the recognition and control of non-self materials. We herein assessed hemagglutination activity in the serum of a deep-sea vent endemic crab, Shinkaia crosnieri, which harbors chemosynthetic epibionts on its plumose setae. Horse and rabbit erythrocytes were agglutinated using this serum (opt. pH 7.5 and opt. temperature 15°C). Agglutinating activity was inhibited by eight kinds of sugars and several divalent cations, did not require any divalent metal ions, and remained detectable even after heating the serum at 100°C for 30 min. By using fluorescently labeled serum, we demonstrated that deep-sea crab serum components bound to the epibionts even in the presence of sugars. This study represents the first immunological assessment of a deep-sea vent endemic crab and demonstrated the possibility of a non-lectin-mediated symbiont-host interaction.
authors.affiliation: Laboratory of Marine Environmental Microbiology, Graduate School of Agriculture, Kyoto University.
authors.forename: So
authors.initials: S
authors.lastname: Fujiyoshi
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Tateno
authors.forename: Tomoo
authors.initials: T
authors.lastname: Watsuji
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Yamaguchi
authors.forename: Daisuke
authors.initials: D
authors.lastname: Fukushima
authors.forename: Sayaka
authors.initials: S
authors.lastname: Mino
authors.forename: Makoto
authors.initials: M
authors.lastname: Sugimura
authors.forename: Tomoo
authors.initials: T
authors.lastname: Sawabe
authors.forename: Ken
authors.initials: K
authors.lastname: Takai
authors.forename: Shigeki
authors.initials: S
authors.lastname: Sawayama
authors.forename: Satoshi
authors.initials: S
authors.lastname: Nakagawa
mesh_terms: D000818:Animals; D001419:Bacteria / Q000254:growth & development; D018407:Bacterial Physiological Phenomena; D033364:Decapoda / Q000382:microbiology*; D004912:Erythrocytes / Q000276:immunology; D006384:Hemagglutination; D006736:Horses; D060086:Hydrothermal Vents; D011817:Rabbits; D044967:Serum / Q000737:chemistry*; D013559:Symbiosis