Effect of cobalt ions on the metabolism of some volatile and polar compounds in the marine invertebrates Mytilus galloprovincialis and Actinia equina

The compositions of the volatile and polar fractions from two coexisting Black Sea invertebrates, the mussel Mytilus galloprovincialis and the beadlet anemone Actinia equina, were established. The main metabolites in the volatile fraction from the investigated animals appeared to be methyl esters of fatty acids and fatty aldehydes. In the polar fraction from both animals low concentrations of free acids and nitrogen-containing compounds were obtained. Free carbohydrates were in much higher concentrations in M. galloprovincialis than in A. equina. Some sterols, probably as polar conjugates, were identified mainly in A. equina. Significant changes among all compounds appeared after treatment of both invertebrates with two different concentrations of cobalt ions. The variety of changes in each invertebrate could be due to their different evolutionary status. The effect of cobalt ions was often stronger at medium cobalt-ion concentrations.     

Experimental habituation of aggression in the sea anemone Actinia equina

Behavioural plasticity in Actinia equina (L.) was examined in experimental contests using a range of pedal disc colour phenotypes, which characterize 3 known, ecologically distinct morphs. With repeated pairing of individuals in auto-phenotypic encounters, habituation was easily induced in the 2 mid-shore morphs, but was not obvious in the less aggressive, low-shore form. Subsequent pairing with a different partner revealed that anemones remained aggressive towards a novel opponent. Following novel contact, repairing of the dark red pedal phenotype with the original partner provided some evidence of retention of habituation to a previous opponent, and thus of a specific inducible memory.     

The fine structure of granular amoebocytes from the gonads of the sea anemoneActinia fragacea (Cnidaria: Anthozoa)

Summary The structure of granular amoebocytes of the intertidal sea anemoneActinia fragacea (Cnidaria: Anthozoa) has been investigated using the electron microscope. Cells from the gonads of large, intact individuals were studied in most detail, but other regions of the anemone were also examined. The amoebocytes are cells of variable appearance which are widely distributed both in the mesogloea and in the epithelial cell layers. They contain numbers of characteristic dense granules, which may enclose spherical cores of greater or lesser electron density. They also contain rough endoplasmic reticulum, Golgi apparatus and a range of inclusions, some of which may have lysosomal origins. They may contain extensive deposits of glycogen, and usually smaller quantities of lipid droplets. They may take on a variety of forms, depending partly on their location within the various types of mesogloea and epithelia. The amoebocytes appear to be motile and phagocytic, and may also be involved in the storage and transport of glycogen. They are involved with gametogenesis, both during the development of the oocytes and spermatogenic cysts and during the resorption of degenerating gametes. Their possible role in the secretion or maintenance of the mesogloea remains uncertain. No evidence of amoebocytes differentiating into other cell types was obtained.     

Action de pesticides chez des insectes en fonction de leur etat physiologique: Etude de 2 insecticides et d'un melange d'herbicides chez les larves aquatiques de cloeon. (Ephemeropteres).

For the larvae of the ephemeron Cloeon, our studies of acute toxicity show that the degradation products of fenthion are more toxic than the insecticide itself.Doses of fenthion and lindane, responsible of a hight mortality, lead to a decrease in the moulting frequency of these larvae. A mixture of herbicides and degradation products of fenthion gave different results.

     

Kunitz-type protease inhibitors from acrorhagi of three species of sea anemones

Sea anemones are rich in biologically active polypeptides such as toxins and protease inhibitors. These polypeptides have so far been isolated from whole bodies, tentacles or secreted mucus. Recently, two novel peptide toxins with crab lethality have been isolated from acrorhagi (specialized aggressive organs elaborated by only certain species of sea anemones belonging to the family Actiniidae) of Actinia equina. This prompted us to survey biologically active polypeptides in the acrorhagi of two species of sea anemones, Anthopleura aff. xanthogrammica and Anthopleura fuscoviridis. No potent crab lethality was displayed by the acrorhagial extracts of both species. However, significantly high protease inhibitory activity was instead detected in the acrorhagial extracts of the two species and also in that of A. equina. From the acrorhagi of A. equina, A. aff. xanthogrammica and A. fuscoviridis, one (AEAPI), one (AXAPI) and two (AFAPI-I and AFAPI-III) protease inhibitors were isolated, respectively. The complete amino acid sequences of the four inhibitors were elucidated by N-terminal sequencing and sequencing of the C-terminal peptide fragment produced upon asparaginylendopeptidase digestion. The determined amino acid sequences revealed that all the four inhibitors are new members of the Kunitz-type protease inhibitor family.     

The ultrastructure of the swimbladder of the toadfish,Opsanus tau L.

Summary The anterior chamber of the swimbladder of the toadfish Opsanus tau L. is lined by a single layer of columnar gas gland cells, cuboidal cells that resemble gas gland cells but are located outside of the gas gland region, and squamous cells. Multilamellar bodies are numerous in the gas gland cells and the cuboidal cells and are present in smaller numbers in the squamous cells. Capillaries lie in the lamina propria directly below the epithelial lining. A thick continuous muscularis mucosae and a submucosa consisting of tightly packed cells, cell processes, and connective tissue may contribute to the impermeability to gases of the wall of the anterior chamber.The posterior chamber of the swimbladder is lined by a single type of squamous epithelial cell. Multilamellar bodies were occasionally observed in these cells also. Other types of cells frequently form a partial second layer between the epithelial lining and the basement lamina. A thin muscularis mucosae lies directly below the basement lamina and the capillaries of the posterior chamber are located in the submucosa. The tunica externa is a layer of dense connective tissue that surrounds both the anterior and posterior chambers. Collagen fibrils in the form of tactoids are present in this layer.Part of this work was submitted by S.M.M. in partial fulfillment of the requirements for the degree of Doctor of Philosophy, Biology Department, Boston University. S.M.M. is grateful for a National Science Foundation Traineeship.     

Secretory tapetum of Brassica oleracea L.: polarity and ultrastructural features

Summary The ultrastructure of the secretory, binucleate tapetum of Brassica oleracea in the micro spore mother cell (MMC) stage through to the mature pollen stage is reported. The tapetal cells differentiate as highly specialized cells whose development is involved in lipid accumulation in their final stage. They start breaking down just before anther dehiscence. Nuclei with dispersed chromatin, large nucleoli and many ribosomes in the cytoplasm characterize the tapetal cells. The wall-bearing tapetum phase ends at the tetrade stage. The dissolution of tapetal walls begins from the inner tangential wall oriented towards the loculus and proceeds gradually along the radial walls to the outer tangential one. The plasmodesmata transversing the radial walls between tapetal cells persist until the mature microspore, long after loss of the inner tangential wall. After wall dissolution, the tapetal protoplasts retain their integrity and position within the anther locule. The tapetal cell membrane is in direct contact with the exine of the microspores/pollen grains and forms tubular evaginations that increase its surface area and appear to be involved in the translocation of solutes from the tapetal cells to the microspores/ pollen grains. The tapetal cells exhibit a polarity expressed by spatial differentiation in the radial direction.     

Pore formation by the sea anemone cytolysin equinatoxin II in red blood cells and model lipid membranes

Summary The interaction ofActinia equina equinatoxin II (EqT-II) with human red blood cells (HRBC) and with model lipid membranes was studied. It was found that HRBC hemolysis by EqT-II is the result of a colloid-osmotic shock caused by the opening of toxin-induced ionic pores. In fact, hemolysis can be prevented by osmotic protectants of adequate size. The functional radius of the lesion was estimated to be about 1.1 nm. EqT-II increased also the permeability of calcein-loaded lipid vesicles comprised of different phospholipids. The rate of permeabilization rised when sphingomyelin was introduced into the vesicles, but it was also a function of the pH of the medium, optimum activity being between pH 8 and 9; at pH 10 the toxin became markedly less potent. From the dose-dependence of the permeabilization it was inferred that EqT-II increases membrane permeability by forming oligomeric channels comprising several copies of the cytolysin monomer. The existence of such oligomers was directly demonstrated by chemical cross-linking. Addition of EqT-II to one side of a planar lipid membrane (PLM) increases the conductivity of the film in discrete steps of defined amplitude indicating the formation of cation-selective channels. The conductance of the channel is consistent with the estimated size of the lesion formed in HRBC. High pH and sphingomyelin promoted the interaction even in this system. Chemical modification of lysine residues or carboxyl groups of this protein changed the conductance, the ion selectivity and the current-voltage characteristic of the pore, suggesting that both these groups were present in its lumen.     

On the egg investments and fertilization reaction inPomatoceros triqueter L.

Summary After a specific time of glutaraldehyde-acrolein fixation, microtubule walls appear to be composed of single 6.5–7.5 nm diameter osmiophilic subunits. Variations in the duration of glutaraldehyde-acrolein and also glutaraldehyde-osmium fixation reveal a two layered wall containing osmiophilic subunits, 4.0–4.5 nm in diameter, arranged radially, in tandem. The double-layered wall is demonstrated by microdensitometer traces. These observations are discussed in relation to previously proposed models of microtubule substructure.     

Cytotoxicity of equinatoxin II from the sea anemoneActinia equina involves ion channel formation and an increase in intracellular calcium activity

Summary Equinatoxin Il is a 20-kDa basic protein isolated from the sea anemoneActinia equina. The aim of our work was to investigate the primary molecular basis for the cytotoxic effects of equinatoxin II in two model systems: single bovine lactotrophs and planar lipid bilayers. Previous work has shown that equinatoxin II produces rapid changes in cell morphology, which are dependent on external calcium. It has also been reported that addition of equinatoxin II increases membrane electrical conductance, which suggests that the cytotoxic action of equinatoxin II involves an increase in the permeability of membranes to Ca²⁺. Extensive changes in cytosolic Ca²⁺ activity are thought to invoke irreversible changes in cell physiology and morphology. In this paper, we show that morphological changes brought about by equinatoxin II in bovine lactotrophs are associated with a rapid rise in cytosolic Ca²⁺ activity, monitored with a fura-2 video imaging apparatus. Moreover, incorporation of equinatoxin II into planar lipid bilayers produces Ca²⁺ permeable ion channels. This suggests that the mode of equinatoxin II cytotoxicity involves the formation of cation (Ca²⁺) permeable channels in cell membranes.     

Funktionsmorphologie des Exkretionsorgans des Spulwurms Ascaris lumbricoides L.

Zusammenfassung Das Seitenkanalsystem von Ascaris lumbricoides wurde elektronenmikroskopisch untersucht. Beim erwachsenen Tier erstreckt sich das in den lateralen Epidermisleisten eingebettete einzellige Organ vom Nervenring bis etwa zur Körpermitte. Im 2. Körperviertel besitzt es kein durchgehendes Kanallumen und erscheint degeneriert. In allen übrigen Bereichen (mit Ausnahme des Ausführungskanals) besitzt es den gleichen Aufbau aus zwei Schichten. Die das Kanallumen begrenzende innere Schicht enthält zahlreiche extraplasmatische Räume, von denen zumindest die am weitesten innen liegenden mit dem Kanallumen kommunizieren. Die äußere Zellmembran besitzt viele Einfaltungen, von denen einige weit in das Cytoplasma hineinragen. Der Gewebeanteil der lateralen Epidermisleisten, der dem Seitenkanalsystem unmittelbar anliegt, enthält sehr viele Interzellularräume, die ein zusammenhängendes Drainage-System bilden. Zur histochemischen Lokalisation von ATP-ase-Aktivität wurden Experimente durchgeführt. Die möglichen Mechanismen der Bildung der Exkretflüssigkeit werden diskutiert unter Berücksichtigung bereits veröffentlichter physiologischer Befunde.

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Ultrastructure and function of the excretory organ of Ascaris lumbricoides L. (Nematoda)

Summary The Excretory organ (H-system) of Ascaris lumbricoides has been investigated electronmicroscopically. In adult animals this single-cell-organ embedded in the lateral lines extends from the nerve ring to approximately the middle of the body.In the second quarter of the body it lacks a continuous canal lumen, and it seems to be degenerated. In all of the other regions (except the stem leading to the excretory pore) it consists of two zones. The inner zone lining the canal lumen contains several extraplasmatic spaces; at least those placed the farthest inside communicate with the canal lumen. The outer cell membrane shows many infoldings, some of which extend deeply into the cytoplasm. The tissue of the lateral line adjacent to the canal system contains very many intercellular spaces which build a coherent intracellular rainage-system. Experiments have been performed in order to localize the ATPase activity histochemically. Possible mechanisms for the forming of the excretory fluid are discussed under consideration of physiological results already published.

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Abkürzungen Ak Ausführungskanal - Bm Basalmembran - Cp Cytoplasmaplatten - lE linke Epidermisleiste - rE rechte Epidermisleiste - Ef Einfaltungen der äußeren Zellmembran - Fb Fibrillenbündel - Go Go Golgiapparat - Hg Hüllgewebe - Is lamelläre Interzellularsubstanz - Iz Interzellularraum - Kl Kanallumen - K Kutikula - Lh Leibeshöhle - Mu Muskelzelle - Mi Mitochondrien - Ms mittlerer Gewebestreifen (= Mittelstreifen) der Epidermisleiste - Mt Mikrotubuli - N Zellkern - No Nucleolus - Ne Nervenring - eP elektronendichte Partikel - sP sphärische Partikel - P Kernpore - Q Querbalken - epR extraplasmatischer Raum - Lho Längsholm - Mf Membranfusion - äS äußere Schicht des Seitenkanalsystems - iS innere Schicht der Längsholme - Sy syncytiale Cytoplasmamasse ohne Interzellularen - V Verzweigungskanal - iZ innere Zone um einen Verzweigungskanal Inauguraldissertation der Mathematisch-Naturwissenschaftlichen Fakultät der Freien Universität Berlin (gekürzt). Herrn Prof. Dr. G. Kümmel danke ich für die Anregung zu diesem Thema und für sein ständiges kritisches Interesse der Untersuchung, Frau C. S. Friedemann für die Anfertigung der Zeichnungen und Fräulein H. Schmidt für technische Assistenz.     

Observations on the ultrastructure ofFrankia sp. in root nodules ofDatisca cannabina L.

Summary The fine structures of the microsymbiont inside the root nodules ofDatisca cannabina have been studied by light, by transmission- and by scanning-electron microscopy. The endophyte is prokaryotic and actinomycetal in nature. The hyphae are septate and branched, diameter 0.3–0.5 m. The tips of hyphae are swollen to form electron-dense, clubshaped to filamentous vesicles, ranging in diameter: 0.4–1.4 m. The endophyte penetrates through walls of the cortial cells. The infected zone is kidney shaped and confined to one side of the acentric stele. The orientation of infection is reversed from other actinorhizae exceptCoriaria. The hyphae are near the host cell wall and vesicles are directed towards the central vacuole. Vesicles are aseptate and no collapsing of the vesicle cell wall (void area) has been observed. Vesicle clusters structures are globular with an opening at one side of the cluster. The host cell is multinucleate or contains a lobed nucleus. Groups of mitochondria are located in between the hyphae, suggesting a strong association between the host and the endophyte for energy supply and amino acid production. The consequences of the inability to separate the mitochondria from the vesicle clusters in nodule homogenates in physiological studies have been discussed.Isolated vesicles clusters showed dehydrogenase activity, indicated by the presence of formazan crystals, after incubation with NADH and NBT. Strongest reducing activity was found within the vesicles. The possible role of filamentous vesicles in nitrogen fixation has been discussed.     

The fine structure of the tarsal glands of the honeybee Apis mellifera L. (Hymenoptera)

Summary Tarsal glands are located in the 6th tarsomere of adult honeybee queens, workers and drones. Their structural features are not cast or sex specific. The glandular epithelium is lined by a thin endocuticular layer. A cuticular pocket is formed from a postimaginal delamination of the cuticle secreted by the glandular epithelium. The apical plasma membrane of the glandular cells shows numerous cristae and microvilli lining large crypts that communicate with the subcuticular space. Pinocytotic vesicles, multivesicular bodies and residual dense bodies are present in the apical part of the glandular cells. The RER is well developed in perinuclear and basal parts of the glandular cells, but the Golgi apparatus is a discrete organelle without secretory granules. No exocytotic secretory structures were observed. To reach the glandular pocket, the non-proteinaceous secretory product must pass across the subcuticular space, the cuticular intima, the space between the intima and the cuticular wall, and the cuticular wall of the glandular pocket.     

Catalase-like crystals in parathyroid gland cells of Rana temporaria L.

Summary Crystalline inclusions in parathyroid gland cell nuclei of Rana temporaria were studied by electron microscopy using a specimen tilting stage. Images were analysed by optical diffraction. Results were compared with X-ray and electron microscopic data of trigonal bovine liver catalase to which a striking resemblance of the inclusions was found.We are grateful to Professor R. Mosebach (Giessen) for discussions, to the Deutsche Forschungsgemeinschaft for a grant (La 229/4) and instruments and to Messrs. Spindler & Hoyer, Göttingen and Messrs. Rank Precision Instruments, Nürnberg for putting apparatus at our disposal and performing diffraction photographs.     

Metabolism of P-particles (polysaccharide particles) in mature pollen grains ofEryngium campestre L. (Apiaceae)

Summary The metabolism of P-particles (polysaccharide particles) was investigated in mature pollen grains ofEryngium campestre L. Numerous P-particles, originating from dictyosome activity, are found to be accumulated near the apertures, followed by mitochondria. A single layer of ER profiles seems to prevent the fusion of the P-particles with the intine. Instead of this, they fuse with each other forming nonmembrane-bounded polysaccharide-aggregates, which subsequently change their granulated structure to an amorphous. Mitochondria together with small vesicles are involved in the conversion-process. The so formed wall precursors pass through the ER and fuse into the intine.     

Fine structure of the terminal organ of the house fly larva,Musca domestica L.

Summary The terminal organs of the cephalic lobes of the house fly larva, Musca domestica L., were studied by scanning and transmission electron microscopy. Six different types of sensilla were found: (1) papilla sensillum, (2) pit sensillum, (3) spot sensillum, (4) modified papilla sensillum, (5) knob sensillum, and (6) scolopidium. The papilla, pit, spot, and modified papilla sensilla have the essential structure of contact chemoreceptors, i.e., the unbranched dendritic tips are exposed externally through a single opening. However, a tubular body, which is a characteristic structure of tactile setae, is also present in some of the dendritic tips. We assume these sensilla serve a dual function—contact chemo- and mechanoreception. The role of the knob sensilla is obscure. The scolopidia present in the dorsal and the terminal organ are probably stress detectors. Two basal bodies occur in the dendritic ciliary region of all sensilla. Both of the basal bodies (except in the scolopidia) give rise to the distal ciliary microtubules as well as the proximal rootlets.This research was supported in part by the Office of Naval Research, PHS Research Grant EC-246 and NIH Training Grant ES-00069. Paper No. 3608 of the North Carolina State University Agricultural Experiment Station journal series. The advise of R. A. Steinbrecht is gratefully acknowledged.     

Morphological aspects of the galactomannan formation in the endosperm ofTrigonella foenum-graecum L. (Leguminosae)

The mode of deposition (secretion) of galactomannan in the cells of the seed endosperm ofTrigonella foenum-graecum has been studied by electron microscopy. In cells which are just beginning to secrete galactomannan there are stacks of rough endoplasmic reticulum (ER). The intracisternal space (containing the enchylema) of the rough ER then swells, becomes vacuolated and forms a voluminous network, with pockets of cytoplasm entrapped within poculiform rough ER. The enchylema contains material which reacts with periodate-thiocarbohydrazidesilver proteinate in a very similar manner to the galactomannan already deposited in the cell wall. It appears that the galactomannan is formed in the intracisternal space of the rough endoplasmic reticulum and then expelled outside the plasmalemma. This mode of deposition contrasts with that of other plant cell wall polysaccharides whose secretion is mediated by Golgi vesicles.Abbreviation ER endoplasmic reticulum This is part six in a series of papers dealing with galactomannan metabolism. Part five: Planta133, 219–222 (1977)     

The First Finding of the Actinia Synandwakia hozawai in the Sea of Okhotsk

The finding of the actinia Synandwakia hozawai in the coastal waters of northern Sakhalin (Sea of Okhotsk) suggests a wider range of this species, which was previously only known to inhabit the coastal waters of eastern Japan. Data are presented on the morphology of the S. hozawai specimen from the Sea of Okhotsk and the types of its nematocysts.