Biochemical sex dimorphism in Lineus lacteus

Egg-specific and sperm-specific proteins fromLineus lacteus females and males were investigated byanalytical electrophoreses. These major sex-specificproteins define the sexual dimorphism of biochemicalmetabolism and are useful for studying vitellogenesisand spermatogenesis. The major yolk proteins in theeggs of the nemertean, Lineus lacteus, wereidentified by gradient gel electrophoresis. The 2vitellin proteins were designated vitellin V1 (460 kDa) andvitellin V2 (260 kDa). The vitellins wereidentified as lipoglycoproteins by selective staining.Three major vitellin subunits (75, 41 and 40 kDa) werefound in oocytes of L. lacteus byelectrophoresis under denaturing conditions(SDS-PAGE). Polyclonal antibodies were raised to eachvitellin subunit. The binding of these rabbitantibodies to vitellins V1 and V2 showed that vitellinV1 contained a single major 75 kDa polypeptide, whilevitellin V2 had two major polypeptides (41 and 40 kDa).Five male-specific proteins (52, 50, 41, 35 and 32 kDa) wereidentified in the sperm of Lineuslacteus by gradient gel electrophoresis. Four lowmolecular weight proteins (18–13 kDa) can also be usedas molecular markers of male sexual maturation. Theseproteins were nucleosomal core histones. The chromatinof L. lacteus sperm contained onlyhistones as no protamines or protamine-like proteinswere detected. But the sperm nucleosomal protein maynot be entirely somatic-histones, as a sperm-specifichistone (Sp H) was also found.     

Species-specific oocyte proteins as molecular markers for Lineus taxonomy

The yolk proteins from the eggs of five species of thenemertean genus Lineus were analysed and theresulting data were used to define L. longissimus, L. sanguineus, L. lacteus, L. ruber, and L. viridis as distinct taxa (species to date). All fivespecies have at least one large (80–60 kDa) and onemedium sized (45–30 kDa) vitellin subunit, but thereare significant differences in the number and sizes ofthe molecular subunits. The large and medium sizedvitellin components of all the species areglycosylated, except for the 145 kDa protein of L. sanguineus. Rabbit antibodies to the L. lacteus vitellin subunits cross-reacted withthe vitellin subunits in the eggs of the otherspecies. The vitellin components of these five speciesof nemertean are very similar. Two species, L.ruber and L. viridis, lay their eggsin gelatinous masses, and the electrophoretic patternsof the jelly proteins show that the physicalconsistency of the jelly depends on molecular weightsof the components. The egg mass of L. viridis contains smaller proteins than the egg massof L. ruber. The repeatablespecies-specific patterns of vitellin componentsprovide a useful complement to the usual taxonomiccriteria.     

Species-specific oocyte proteins as molecular markers for Lineus taxonomy

The yolk proteins from the eggs of five species of thenemertean genus Lineus were analysed and theresulting data were used to define L. longissimus, L. sanguineus, L. lacteus, L. ruber, and L. viridis as distinct taxa (species to date). All fivespecies have at least one large (80–60 kDa) and onemedium sized (45–30 kDa) vitellin subunit, but thereare significant differences in the number and sizes ofthe molecular subunits. The large and medium sizedvitellin components of all the species areglycosylated, except for the 145 kDa protein of L. sanguineus. Rabbit antibodies to the L. lacteus vitellin subunits cross-reacted withthe vitellin subunits in the eggs of the otherspecies. The vitellin components of these five speciesof nemertean are very similar. Two species, L.ruber and L. viridis, lay their eggsin gelatinous masses, and the electrophoretic patternsof the jelly proteins show that the physicalconsistency of the jelly depends on molecular weightsof the components. The egg mass of L. viridis contains smaller proteins than the egg massof L. ruber. The repeatablespecies-specific patterns of vitellin componentsprovide a useful complement to the usual taxonomiccriteria.     

A taxonomic catalogue of Japanese nemerteans (phylum Nemertea)

A literature-based taxonomic catalogue of the nemertean species (Phylum Nemertea) reported from Japanese waters is provided, listing 19 families, 45 genera, and 120 species as valid. Applications of the following species names to forms previously recorded from Japanese waters are regarded as uncertain: Amphiporus cervicalis, Amphiporus depressus, Amphiporus lactifloreus, Cephalothrix filiformis, Cephalothrix linearis, Cerebratulus fuscus, Lineus vegetus, Lineus bilineatus, Lineus gesserensis, Lineus grubei, Lineus longifissus, Lineus mcintoshii, Nipponnemertes pulchra, Oerstedia venusta, Prostoma graecense, and Prostoma grande. The identities of the taxa referred to by the following four nominal species require clarification through future investigations: Cosmocephala japonica, Dicelis rubra, Dichilus obscurus, and Nareda serpentina. The nominal species established from Japanese waters are tabulated. In addition, a brief history of taxonomic research on Japanese nemerteans is reviewed.     

The nucleotide sequences of 5S rRNAs from two ribbon worms: Emplectonema gracile contains two 5S rRNA species differing considerably in their sequences.

The nucleotide sequences of 5S rRNAs from two nemerteans (ribbon worms), Lineus geniculatus and Emplectonema gracile have been determined. Emplectonema has two 5S rRNA species that are composed of 119 and 120 nucleotides, respectively. The sequences of these two 5S rRNAs differ at 22 positions. On the other hand, only a single 5S rRNA species was found in Lineus. The sequence similarity percents are 88% (Lineus/Emplectonema longer 5S rRNA), 82% (Emplectonema longer/Emplectonema shorter) and 80% (Lineus/Emplectonema shorter). The comparisons of these sequences with those of other organisms suggest that the phylum Nemertinea is most related to the Mollusca (91%) and the Rotifera (89%), but not to fresh-water planarias (72%).     

Fortgesetzte Studien Über die Regeneration der Nemertinen

Ohne Zusammenfassung Wir bezeichnen diesen Abschnitt unsrer fortgesetzten Studien über die Regeneration der Nemertinen betreffendLineus lacteus Rathke mit II, da der erste Abschnitt sich aufLineus ruber Müll, bezog (vgl. das Literaturverzeichnis Nr. 8–10, 13 u. 14).     

Irpex hydnoides, sp. nov. is new to science, based on morphological, cultural and molecular characters

Irpex, one of the most common polypore genera, is easily identified by macro- and microscopic characters. During field trips to Korea's Kangwon Province, some Irpex specimens with conspicuous morphological differences from I. lacteus were collected. Cultural characters and molecular evidence differentiated this new strain from I. lacteus, and this taxon is proposed as I. hydnoides sp. nov.     

Isoenzyme differences between three closely related species of Lineus (Heteronemertea)

Starch-gel electrophoresis was employed to compare six enzymes in three closely related species of nemertean worms, Lineus ruber (Müller, 1774), Lineus sanguineus (Rathke, 1799), and Linens viridis (Müller, 1774). Differences in mobility recorded for most of the enzyme loci examined support the hypothesis that these nemerteans are distinct taxa.     

Biodegradation of endocrine-disrupting bisphenol A by white rot fungus Irpex lacteus

Biodegradation of endocrine-disrupting bisphenol A was investigated with several white rot fungi (Irpex lacteus, Trametes versicolor, Ganoderma lucidum, Polyporellus brumalis, Pleurotus eryngii, Schizophyllum commune) isolated in Korea and two transformants of T versicolor (strains MrP 1 and MrP 13). I. lacteus degraded 99.4% of 50 mg/l bisphenol A in 3 h incubation and 100% in 12 h incubation. which was the highest degradation rate among the fungal strains tested. T. versicolor degraded 98.2% of 50 mg/l bisphenol A in 12 h incubation. Unexpectedly, the transformant of the Mn-repressed peroxidase gene of T. versicolor, strain MrP 1, degraded 76.5% of 50 mg/l bisphenol A in 12 h incubation, which was a lower degradation rate than wild-type T. versicolor. The removal of bisphenol A by I. lacteus occurred mainly by biodegradation rather than adsorption. Optimum carbon sources for biodegradation of bisphenol A by I. lacteus were glucose and starch, and optimum nitrogen sources were yeast extract and tryptone in a minimal salts medium; however, bisphenol A degradation was higher in nutrient-rich YMG medium than that in a minimal salts medium. The initial degradation of endocrine disruptors was accompanied by the activities of manganese peroxidase and laccase in the culture     

Conversion of a postocellar into an ocellar region as a transdetermination event occurring in adult ribbonworms

Transections and grafting experiments performed in Lineus ruber rostral ends allowed us to generate ribbonworms with a duplication of the postocellar region combined with a deletion of the ocellar region. In such homeotically reconstructed animals, the syngeneic postocellar region transdifferentiated into an ocellar region with functional eyes while the allogeneic postocellar region underwent no transformation. In this case, transdifferentiation is a morphogenetic process leading to the restoration of the normal antero-posterior (A-P) axis pattern in adult worms. This regulative conversion of one adult body region into another, which so far has not been described in any bilaterian animal, is comparable with transdetermination of larval imaginal discs in Drosophila. Under certain conditions, Drosophila, wing imaginal disc cells express the eyeless master control gene and give rise to eyes. Here, we show in Lineus that the transposition of postocellar tissue into the ocellar location causes expression of the eyeless ortholog LsPax-6 and results in eye development. Our results in Lineus clearly suggest that transdifferentiation of adult body regions moved to a different position along the A-P axis is similar to transdetermination of the larval imaginal disc cells which are determined, but not yet differentiated.     

Antarctic nemerteans: Heteronemertea– descriptions of new taxa, reappraisals of the systematic status of existing species and a key to the heteronemerteans recorded south of latitude 50oS

Twenty-three species representative of 15 heteronemertean genera are recorded from Antarctic and Subantarctic waters south oflatitude 50^oS. Five new genera are established and seven new species are fully described and illustrated. These are Cephalurichus antarcticus gen. et sp. nov., Dokonemertes magellanensis gen. et sp. nov., Dokonemertes macquariensis sp. nov., Micrellides multiperula gen. et sp. nov., Paramicrurinella falklandica gen. et sp. nov., Parborlasia landrumae sp. nov. and Zodionemertes chilensis gen. et sp. nov. Baseodiscus antarcticus Baylis, Antarctolineus scotti (Baylis), Lineus longifissus (Hubrecht) and Parborlasia fueguina Serna de Esteban & Moretto are redescribed and illustrated and the nature of rhynchodaeal pouches protruding into the cephalic blood lacunae of Parborlasia corrugatus (Mcintosh) is reexamined and discussed. The main anatomical characters of the remaining 11 species are recorded and it is concluded that of these only Parapolia grytvikenensis Wheeler, Cerebratulus malvini Wheeler, Chilineus glandulosa (Burger), Huilkia ushuaiensis Serna de Esteban & Moretto, Micrura pacifica Friedrich and Wiolkenia friedrichi Serna de Esteban & Moretto can at present be accepted as valid, although incompletely described, taxa. Cerebratulus larseni Wheeler, Cerebratulus validus Bürger, Lineus autrani Joubin and Lineus turqueli Joubin are so poorly and inadequately described that their taxonomic status cannot be verified, and the recorded occurrence of Lineus nigricans Burger in southern latitudes cannot be substantiated on the available evidence. Maps showing the recorded distribution of all the species are included and a key to the 18 validated species is provided.     

Weitere Studien über die Regeneration der Nemertinen

Ohne ZusammenfassungDie drei ersten Teile dieser Studien, welche I. Technisch-methodische Vorbemerkungen, Beobachtungen am Lebenden usw., II. Manche Strukturunterschiede zwischen der breiten und dünnen Form desLineus ruber Müll. usw., und III. Die inneren Vorgänge bei der Regeneration der Vorderteile (Kopfabschnitte) desLineus ruber — enthielten, wurden in diesem Archiv, Bd. XXX (Festband I), 1910 veröffentlicht.     

The nemerteans (Nemertea) of Rottnest Island, Western Australia

Seventeen species of marine nemerteans are reported from Rottnest Island, Western Australia. Eight new species and four new genera are described and illustrated; these are the heteronemerteans Kohnia rottnestensis gen. et sp. n., Lineus bioculatus sp. n., Lineus gilviceps sp. n., Micrura callima sp. n. and Uricholemma nigricans gen. et sp. n., and the monostiliferous hoplonemerteans Aenigmanemertes norenburgi gen. et spn. n., Crybelonemertes arenicolus gen. et sp. n. and Tetrastemma tristibruna sp. n. A key for the field identification of the nemerteans of Rottnest Island is provided.     

Impact of the nemertean Lineus viridis on its polychaete prey on an intertidal sandflat

Interactions of the predator Lineus viridis (O. F. Muller 1774) with infaunal polychaetes were investigated in the German Wadden Sea. L. viridis is the dominant heteronemertean in this intertidal area with a mean abundance of 14 individuals per square meter. Predator enclosure experiments in the field revealed that L. viridis preyed on predatory polychaetes. The preferred prey species was Nereis diversicolor; others were Anaitides maculata. Nephtys hombergii and Harmothoe sarsi. These results were supported by a series of feeding experiments in the laboratory. The rate of consumption was estimated by laboratory and field experiments. The feeding rate of Lineus viridis was estimated by laboratory enclosure experiments to 5.6 g ashfree dry weight (AFDW) per square meter annually.     

Cloning and expression in Pichia pastoris of an Irpex lacteus rhamnogalacturonan hydrolase tolerant to acetylated rhamnogalacturonan

In order to produce a recombinant rhamnogalacturonase from the basidiomycete Irpex lacteus using a molecular approach, PCR primers were designed based on a sequence alignment of four known ascomycete rhamnogalacturonases. Using 5' and 3' rapid amplification of cDNA ends (RACE) experiments, a 1,437-bp full-length cDNA containing an open reading frame of 1,329 bp was isolated. The corresponding putative protein sequence is of 443 amino acids and contains a secretion signal sequence of 22 amino acids. The theoretical mass of this protein is 44.6 kDa with a theoretical isoelectric point of 6.2. The amino acid sequence shared not only significant identities with ascomycete and basidiomycete putative rhamnogalacturonases but also complete similarity with peptides obtained from a recently purified rhamnogalacturonase from I. lacteus. The recombinant protein was successfully expressed in active form in Pichia pastoris. SDS-PAGE assay demonstrated that the recombinant enzyme was secreted in the culture medium and had a molar mass of 56 kDa. This recombinant rhamnogalacturonan hydrolase exhibited a pH optimum between 4.5 and 5 and a temperature optimum between 40°C and 50°C, which correspond to that of the native rhamnogalacturonase from I. lacteus. The study of its specificity through reaction products analysis showed that it was highly tolerant to the presence of acetyl groups on its substrate, even more than the native enzyme.     

Life history of Lineus viridis (Müller, 1774) (Heteronemertea, Nemertea)

Lineus viridis is a common nemertean species of North-Atlantic intertidal sand flats. Its mating behaviour is peculiar insofar as this species is reported to be polyandric. However, detailed information on this topic is lacking. In order to get more data on the reproduction, oogenesis and life history of this species, a population in the Wadden Sea on the Isle of Sylt (North Sea) was studied between 2005 and 2011. We conducted regular surveys, during which we sampled, measured and recorded the sex status of 25–100 individuals at each sampling event; at least three individuals were fixed for histological studies at each sampling date. In addition, animals were kept in the laboratory for 3?years to complement field data on sexual identity. Lineus viridis was found to reproduce annually in several successive year; the females are significantly larger than the males. Oogenesis starts in spring, shortly after the preceding reproductive period, and continues until the end of December. Spermiogenesis starts in late autumn and also ends late in December. During mating, several males are generally found crawling on a single female, which forms a cocoon that encloses both the female and the associated males. Fertilization is internal. While females discharge all of their eggs during a single mating event and lose more than 40% of their wet weight, males only empty a few of their gonads, and are thus able to fertilize more than one female. Our study clearly shows that Lineus viridis is a perennial, iteroparous species with a pronounced sexual size dimorphism. During this long-term study, no evidence for sequential hermaphroditism has been found. The observed polyandric mating system in this species raises further questions regarding mate and sperm competition that deserve additional research.     

Monoamine- and peptide-containing elements in the body wall and nervous trunks of nemerteans

Localization and morphological peculiarities of cateholamine-containing (CA-C), serotonin-(5HTIR), neurotensin-(NT-IR) and FMRFamide-immunoreactive (FMRFa-Ir) cells and processes in the body wall and lateral nervous trunks of nemerteans were investigated. The following nemertean species from three orders occurring in the White Sea were studied by fluorescent histochemistry and by immunohistochemistry: Lineus viridis, Lineus ruber and Cerebratulus sp. (Heteronemertini), Cephalothrix linearis (Palaeonemertini), and Amphiporus lactifloreus (Hoplonemertini). The similarity and characteristics of morphological types of monoamine-and peptide-containing elements, their distribution and possible participation in regulation of some functions in different nemertean species and in other invertebrates are discussed. We suggest that 5HT-IR and CA-C bi-and multipolar intra-and subepidermal open-type cells prevailing in the body wall perform a receptive function, while the FMRFa-Ir and NT-IR neurons of the nerve trunks and body wall are responsible for efferent innervation of musculature and connections within the nervous system.     

一株产木质素降解酶真菌的分离与鉴定

从自然界中分离到一株产木质素降解酶真菌.平板显色反应显示,该菌株具有产多种木质素降解酶的能力,并通过酶活力测定得到证实.为确定该菌株的分类地位,对其ITS序列进行了扩增并测序,并利用MEGA4.0生物学软件计算其与同属其它菌株的遗传距离并构建系统发育树,在分子水平上确定它们之间的亲缘关系.试验结果表明,该菌株的ITS序列与Irpex lacteus乳白耙菌序列相似度达99%,且与Irpex lacteus XSD-2亲缘关系最近.     

Lineus as a model for studying developmental processes in animals reconstructed from adult pieces

The difficulties that prevent reconstruction of animals by piecing together body fragments from several adults are overcome by using nemerteans of the genus Lineus. For 25 years I have managed to make viable composite worms by grafting body parts cut out of Lineus specimens either from the same clonal strain (syngeneically reconstructed worms) or from the same species (allogeneically reconstructed worms) or else from different species (xenogeneically reconstructed worms). Body reconstruction has usually been carried out orthotopically, i.e., the components of composite animals have been selected so as to be anatomically complementary. However, reconstruction has been made heterotopically when it was essential to obtain morphogenetic events in the adults. Here, I shall review some of the developmental processes that took place in such reconstructed animals. First, I shall report immune responses in composite worms derived from various combinations of body pieces grafted together. Second, I shall study sex differentiation during gonad development in growing or regenerating chimeric worms made by the grafting of male and female components. I shall refer also to gonadogenesis in the asexual progeny of bipartite chimeras derived from lateral body halves of both sexes fused together (clones of bilaterally allophenic worms). Third, I shall analyze regulative processes (regeneration, transgeneration) during localized morphogenesis occurring in heterotopically reconstructed worms. The data show how reconstructed Lineus may be exploited to increase our knowledge of developmental mechanisms, especially in the misunderstood field of organismal pattern homeostasis.     

糖脂类生物表面活性剂的特性及其对白腐真菌降解蒽的强化作用

【目的】对铜绿假单胞菌(Pseudomonas aeruginosa)所产生物表面活性剂的稳定性进行分析,考察该生物表面活性剂对乳白耙齿菌F17(Irpex lacteus F17)降解蒽的强化作用。【方法】采用三氯甲烷萃取的方法从铜绿假单胞菌的发酵液中提取生物表面活性剂,采用表/界面张力仪测定该生物表面活性剂在不同条件下的表面张力值,对其进行稳定性研究。在乳白耙齿菌F17降解蒽的过程中加入适量的生物表面活性剂,测定蒽的降解率,探讨其对蒽生物降解的强化作用。【结果】铜绿假单胞菌所产生物表面活性剂的临界胶束浓度为40 mg/L,在15-150°C及pH 6.0-13.0范围内表现出优良的稳定性,对盐浓度的耐受性也很高。在蒽的生物降解过程中,生物表面活性剂能极大地促进蒽的降解,在生物表面活性剂浓度为50 mg/L时,第15天蒽的降解率达到了82.9%。生物表面活性剂在接种乳白耙齿菌F17前1天加入培养基中,能更好地促进蒽的降解。与化学表面活性剂相比,生物表面活性剂对蒽降解的强化作用更显著。【结论】该生物表面活性剂性能优良、稳定性好,能够显著强化乳白耙齿菌F17对蒽的降解,具有良好的应用前景。