Association of various types of epi-bacteria with Halicryptus spinulosus (Priapulida)

Abstract

The priapulid worm Halicryptus spinulosus von Siebold, from a sulfide-rich braclush water habitat, is associated with various types of epibacteria. TEM observations reveal bacteria morphologically similar to Thiobacillus and Leucothrix/Thiothrix. The Thiobacillus-type is the dominant organism; it occurs in microcolonies throughout the bacterial layer and frequently contains carboxysomes, which are indicative of chemoautotrophic activity. Analyses of ribulose-1,5-bisphosphate carboxylase, X-ray microanalysis, and the ratio of stable 13C/"C and ' 5~/ ' 4~ isotopes do not indicate a participation of chemoautotrophic bacteria in the nutrition of the worm. It is concluded that the epibacteria might be able to detoxify the hydrogen sulflde to some degree, provided oxygen or nitrate is available, and that the worms must rely on their own metabolism of hydrogen sulfide detoxification whenever their environment becomes anoxic.

Symbiosis of epi- and endocuticular bacteria with Helicoradomenia spp. (Mollusca, Aplacophora, Solenogastres) from deep-sea hydrothermal vents

“…1 were not associated with a specific region of the host bodies. Similar to the shallow-water priapulid Halicryptus spinulosus von Siebold, 1849 multi-partner association (Oeschger & Schmaljohann 1988) a morphologically diverse microbial community was found on the entire cuticle of H. cf. acredema and Helicoradomenia sp.…”

“…2h) are outstanding. According to Oeschger & Schmaljohann (1988) the rippled appearance of the cell surface results from an undulating cell wall; however, it is also possible that this is a fixation artifact. The internal membranes of these bacteria point to the occurrence of type II methanotrophs, which are characterized by intracytoplasmic membranes arranged in concentric rings at the periphery of the cytoplasm (Nelson & Fisher 1995).…”

Physiology of sulfide detoxification in the isopod Saduria (Mesidotea) entomon

“…Thus a high tolerance to hydrogen sulfide in fauna from sulfide-rich environments has been shown by e.g. Jacubowa & Malm (1931), Theede et al (1969), Oertzen & Schlungbaum (1972), Degn & Kristensen (1981), Oeschger & Schmaljohann (1988), Bagarinao & Vetter (1989), Oeschger & Storey (1990), and Vismann (1990). Sulfide catalysis has been demonstrated in a number of sediment-dwelling species (Pate1 & Spencer 1963, Powell et al 1979, Powell & Somero 1985, 1986, Anderson et al 1987, Vetter et al 1987, Powell & Arp 1989, Vismann 1990).…”

Attachment mechanism in a highly specific association between ectosymbiotic bacteria and marine nematodes

“…Representatives are Kentrophoros spp. (Karyorelictea, Ciliophora;Fenchel & Finley 1989), Zoothamnium niveum (Oligohymenophora, Ciliophora; Bauer- Nebelsick et al 1996a,b, Ott et al 1998, Stilbonematinae (Desmodoridae, Nematoda; Ott & Novak 1989, Ott et al 1991, Alvinella pompejana (Alvinellidae, Polychaeta; Cary & Stein 1998), Halicryptus spinulosus (Priapulida; Oeschger & Schmaljohann 1988) and Rimicaris exoculata (Bresiliidae, Crustacea; Polz & Cavanaugh 1995). Except for Z. niveum, none of the thiotrophic ectosymbioses could be cultivated so far.…”