title: Cellular origin of dysiherbaine, an excitatory amino acid derived from a marine sponge.
abstract: The cellular origin of dysiherbaine, a marine-sponge toxin, was investigated immunohistochemically by using an anti-dysiherbaine antibody. Dysiherbaine-like immunoreactivity was found to be localized in spherical cells harbored in the sponge mesohyl. A combination of ribosomal RNA gene (rDNA) analysis and cell-morphology analysis revealed that the spherical cells were Synechocystis cyanobacteria. However, the sponge, identified as Lendenfeldia chondrodes on the basis of its rDNA sequence, appeared to contain two different chemotypes--dysiherbaine-producing (DH+) and nondysiherbaine-producing (DH-)--both of which inhabited the same region. Synechocystis cells in the DH- sponge were not labeled with antibody, although the 16S rDNA gene profile of the cyanobacteria in the DH- sponge was indistinguishable from that of the cyanobacteria in the DH+ sponge. On the basis of these results, we hypothesize that dysiherbaine is a metabolite of certain varieties of endosymbiotic Synechocystis sp.
authors.affiliation: Kitasato University, School of Fisheries Sciences, Sanriku-cho, Ofunato, Iwate 022-0101, Japan. r.sakai@kitasato-u.ac.jp
authors.forename: Ryuichi
authors.initials: R
authors.lastname: Sakai
authors.forename: Kazufumi
authors.initials: K
authors.lastname: Yoshida
authors.forename: Atsuko
authors.initials: A
authors.lastname: Kimura
authors.forename: Kanae
authors.initials: K
authors.lastname: Koike
authors.forename: Mitsuru
authors.initials: M
authors.lastname: Jimbo
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Koike
authors.forename: Atsushi
authors.initials: A
authors.lastname: Kobiyama
authors.forename: Hisao
authors.initials: H
authors.lastname: Kamiya
mesh_terms: D000409:Alanine / Q000031:analogs & derivatives* / Q000737:chemistry / Q000378:metabolism; D000818:Animals; D019086:Bridged Bicyclo Compounds, Heterocyclic / Q000737:chemistry* / Q000378:metabolism*; D000458:Cyanobacteria / Q000502:physiology; D004275:DNA, Ribosomal / Q000737:chemistry; D018846:Excitatory Amino Acids / Q000737:chemistry* / Q000378:metabolism*; D007150:Immunohistochemistry; D013058:Mass Spectrometry; D046529:Microscopy, Electron, Transmission; D016253:Microscopy, Immunoelectron; D015394:Molecular Structure; D009792:Oceans and Seas; D010802:Phylogeny; D011161:Porifera / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism* / Q000648:ultrastructure; D013559:Symbiosis
chemical_list: D019086:Bridged Bicyclo Compounds, Heterocyclic; D004275:DNA, Ribosomal; D018846:Excitatory Amino Acids; C121741:dysiherbaine; D000409:Alanine