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1.
Three species of gorgonians (Primnoa pacifica, Calcigorgia japonica, and Thouarella superba) are reported as new records for the northwestern Sea of Japan; one of them (Calcigorgia japonica sp. n.) has been described as a new species. Variations of colony morphology in some species are described; the taxonomical value of specific characters is discussed. The geographical range of Primnoa pacifica in the northwestern Pacific is shown to be wider than was considered earlier. Variations of sclerite morphology (number of marginal plates, presence of additional basal plates, and number of marginal spines on the basal plate) are regarded as intracolonial or intraspecific variability. The distribution range of Thouarella superba described earlier from the Aleutian Islands (Nutting, 1912) was shown to extend into the low-boreal part of the boreal Pacific. An examined specimen of Paragorgia sp. differed from all known species and appeared similar only to P. regalis Nutting, 1912 reported from the eastern coast of Japan. The most distinctive characters of Calcigorgia japonica sp. n. were the shape of polyp, with a thin lower part looking like folded podia (in fixed specimens) and the presence of two types of clubs scattered among the sclerites of the polyp.  相似文献   

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Mirabilicoxa kussakini sp. nov. is described from the bathyal of the northwestern Sea of Japan. This is the first record of the genus Mirabilicoxa Hessler, 1970 in the Sea of Japan. The new species is most similar to M. similis (Hansen, 1916), M. plana Hessler, 1970 and M. minuta Hessler, 1970 from the Northwest Atlantic. It differs from them in having a more elongated body (4.1–4.5 times as long as wide) and antenna 1 with the terminal article 5 shorter than article 4.  相似文献   

4.
Alaimella cincta Cobb 1920 and Alaimella macramphis sp. n. are described and illustrated. Both the species were first recorded for the White Sea in northern Russia. A. cincta occurs in the shells of the agglutinated foraminiferan Reophax curtus, as well as freely in bottom sediments. A. macramphis sp. n. is described from a single male sampled from bottom sediments. A. macramphis sp. n. is distinguished from two previously known species of Alaimella (A. cincta Cobb 1920 and A. truncate Cobb 1920) by having a longer body, longer cephalic setae, and a wide amphid equal to the respective body diameter. The new species also differs from A. truncate by the distinct striation of the cuticular annulations. The Alaimella species are additionally characterized by having a posterior glandular widening of the esophagus. An emended diagnosis of the genus Alaimella Cobb 1920 and a key for species identification are provided.  相似文献   

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Studies of Marenzelleria species were often hampered by identification uncertainties when using morphological characters only. A newly developed PCR/RFLP protocol allows a more efficient discrimination of the three species Marenzelleria viridis, Marenzelleria neglecta and Marenzelleria arctia currently known for the Baltic Sea. The protocol is based on PCR amplification of two mitochondrial DNA gene segments (16S, COI) followed by digestion with restriction enzymes. As it is faster and cheaper than PCR/sequencing protocols used so far, the protocol is recommended for large-scale analyses. The markers allow an undoubted determination of species irrespective of life stage or condition of the worms in the samples. The protocol was validated on about 950 specimens sampled at more than 30 sites of the Baltic and the North Sea, and on specimens from populations of the North American east coast. Besides this test we used mitochondrial DNA sequences (16S, COI, Cytb) and starch gel electrophoresis to further investigate the distribution of the three Marenzelleria species in the Baltic Sea. The results show that M. viridis (formerly genetic type I or M. cf. wireni) occurred in the Öresund area, in the south western as well as in the eastern Baltic Sea, where it is found sympatric with M. neglecta. Allozyme electrophoresis indicated an introduction by range expansion from the North Sea. The second species, M. arctia, was only found in the northern Baltic Sea, where it sometimes occurred sympatric with M. neglecta or M. viridis. For Baltic M. arctia, the most probable way of introduction is by ship ballast water from the European Arctic. There is an urgent need for a new genetic analysis of all Marenzelleria populations of the Baltic Sea to unravel the current distribution of the three species.  相似文献   

7.
The development of Fusarium culmorum and Pseudomonas fluorescens in soil, and the relations between them, were studied using membrane filters containing the fungus, the bacterium, or both microorganisms; the filters were incubated in soil. F. culmorum was identified by indirect immunofluorescence; the GUS-labeled strain was used to visualize P. fluorescens. It was found that F. culmorum introduced in soil can develop as a saprotroph, with the formation of mycelium, macroconidia, and a small amount of chlamydospores. Introduction of glucose and cellulose resulted in increased density of the F. culmorum mycelium and macroconidia. P. fluorescens suppressed the development of the F. culmorum mycelium in soil, but stimulated chlamydospore formation. Decreased mycelial density in the presence of P. fluorescens was more pronounced in soil without additions and less pronounced in the case of introduction of glucose or cellulose. F. culmorum had no effect on P. fluorescens growth in soil.  相似文献   

8.
The taxonomic composition of marine mycelial fungi was determined in the interstitial habitats of the Vostok Bay littoral (Peter the Great Bay, the Sea of Japan). A total of 39 species of ascomycetes and anamorphic fungi were detected and identified. The predominant species of the intertidal zone were Corollospora maritima, C. lacera, Carbosphaerella leptosphaerioides, Arenariomyces trifurcatus (Ascomycota), Alternaria alternata, Scolecobasidium arenarium, and Zalerion maritimum (anamorphic fungi). The complete list of species of obligately marine ascomycetes and anamorphic fungi from the interstitial habitats of the Vostok Bay littoral is presented for the first time  相似文献   

9.
Morphological and quantitative characteristics of the growth variability of two Parvancorina species were analyzed based on new abundant material from the Vendian of the White Sea. Growth variability in this problematic taxon appears to be wider than previously suggested. We found allometric growth in the White Sea population of P. minchami Glaessner, 1958, in contrast to isometric growth in Australian representatives of the species. Another White Sea species, P. sagitta Ivantsov, 2004, shows gradual formation of anchor-shaped structure in juveniles. Based on Australian material, it was previously believed that this structure did not change during ontogeny. These two distinctive features together with a strong variability of age-related measurements distinguish Parvancorina from other early arthropods (Scania, Primicaris), and cast doubt on the growth pattern as an argument in favor of the arthropodan nature of Parvancorina.  相似文献   

10.
The prevalence of antibodies to morbilliviruses, Brucella and Toxoplasma was studied in the Black Sea bottlenose dolphin Tursiops truncatus ponticus maintained in captivity. Serum from 59 dolphins was tested, and in most cases the tests were repeated 2–4 years later. Antibodies to the tested pathogens were detected in 69% of the dolphins. Sixteen Black Sea bottlenose dolphin maintained in captivity (27%) had antibodies to two, or even three, of the pathogens. No apparent signs of infection were found in the dolphins; however, the high prevalence of antibodies to the morbilliviruses, Brucella, and Toxoplasma may indicate an important role of dolphins in the ecology of these pathogens.  相似文献   

11.
The byssus production of the blue mussel Mytilus edulis L. was studied in the laboratory in the presence of the metabolites of the following animals: a predator (a starfish Asterias rubens L.) and several species competing with the mussel in White Sea fouling communities (a bivalve Hiatella arctica L. and a solitary ascidian Styela rustica L.). The byssus threads and attachment plaques produced by each mussel per day were counted. The number of byssus threads and plaques was smallest in pure sea water and in the presence of metabolites produced by conspecific individuals.  相似文献   

12.
Horizontal and vertical distribution of algae in Ahnfeltia tobuchiensis beds was studied in the area of Mt. Stolovaya in Amursky Bay, Sea of Japan. Thirty-four species of macroalgae (2 species of Chlorophyta, 26 Rhodophyta, and 6 Ochrophyta) were found in the area of study. Two fields of the unattached alga Ahnfeltia were located opposite Mt. Stolovaya; they differed in area, macrophyte stock, number and biomass of attendant species, hydrochemical and light conditions. A monodominant Ahnfeltia tobuchiensis community formed in the southern field and a bidominant community of Ahnfeltia tobuchiensis + Ahnfeltiopsis flabelliformis developed in the northern field. It is suggested that the horizontal distribution of common macrophyte species in the Ahnfeltia beds at Mt. Stolovaya is conditioned by the amount of photosynthetically active radiation (PAR) reaching the surface of the algal bed. Differences in tolerance of Ahnfeltia and attendant species to shadowing and in light conditions across the alga stratum define the vertical distribution of algae within the bed. Chondrus armatus and Ptilota filicina were found mainly in the upper layer of the algal bed. A. tobuchiensis, A. flabelliformis, Chaetomorpha linum, and Coccotylus orientalis extended across the entire thickness of the bed.  相似文献   

13.
The mutual effects of several fouling species (the bivalves Mytilus edulis and Hiatella arctica and a solitary ascidian Styela rustica) on their growth rate and mortality were studied through field experiments. The interactions between S. rustica and H. arctica appeared to be the least antagonistic. In contrast, the mussel was the most “aggressive” species with regard to both competitors. It was observed that the ascidians died, because they were intensively braided and gummed up with the byssus threads of the mussels. However, in some cases the intraspecific competition was stronger than the interspecific one.  相似文献   

14.
Bioenergetics of the aerobic bacteriochlorophyll a-containing (BCl a) bacterium (ABC bacterium) Roseinatronobacter thiooxidans is a combination of photosynthesis, oxygen respiration, and oxidation of sulfur compounds under alkaliphilic conditions. The photosynthetic activity of Rna. thiooxidans cells was established by the photoinhibition of cell respiration and reversible photobleaching discoloration of the BCl a of reaction centers (RC), connected by the chain of electron transfer with cytochrome c 551 oxidation. The species under study, like many purple bacteria and some of the known ABC bacteria, possesses a light-harvesting pigment-protein (LHI) complex with the average number of 30 molecules of antenna BCl a per one photosynthetic RC. Under microaerobic growth conditions, the cells contained bc 1 complex and two terminal oxidases: cbb 3-cytochrome oxidase and the alternative cytochrome oxidase of the a 3 type. Besides, Rna. thiooxidans was shown to have several different soluble low- and high-potential cytochromes c, probably associated with the ability of utilizing sulfur compounds as additional electron donors.  相似文献   

15.
The yeasts of the Malassezia genus are opportunistic microorganisms and can cause human and animal infections. They are commonly isolated from the skin and auricular canal of mammalians, mainly dogs and cats. The present study was aimed to isolate Malassezia spp. from the acoustic meatus of bats (Molossus molossus) in the Montenegro region, “Rondônia”, Brazil. From a total of 30 bats studied Malassezia spp. were isolated in 24 (80%) animals, the breakdown by species being as follows (one Malassezia sp. per bat, N = 24): 15 (62.5%) M. pachydermatis, 5 (20.8%) M. furfur, 3 (12.5%) M. globosa and 1 (4.2%) M. sympodialis. This study establishes a new host and anatomic place for Malassezia spp., as it presents the first report ever of the isolation of this genus of yeasts in the acoustic meatus of bats.  相似文献   

16.
Across Western Europe and North America, many bumblebee species are currently undergoing drastic declines in their abundance and ranges, primarily as a result of habitat fragmentation. In contrast, a smaller number of species are seemingly unaffected by this and remain common. The UK Biodiversity Action Plan-designated Bombus ruderatus belongs to the former group while B. hortorum belongs to the latter. These two species are sympatric and remarkably similar in morphology. There are no diagnostic characters for workers and male genitalia are illustrated with the same diagram in standard keys. Isolated records of putative B. ruderatus occur amongst a mass of records for B. hortorum. This raises two important issues: first, are B. ruderatus and B. hortorum ‘good’ species? Second, if they are, can the uncertainty over their identification be resolved? We present COII and cytochrome b mtDNA sequence data from these and other Bombus species. Molecular data and coat colour characters are in concordance and confirm that B. ruderatus and B. hortorum should be regarded as separate species (although coat colour alone is an unreliable diagnostic character for many individuals). Confirmation of the specific status of B. ruderatus allows the work on the conservation of this species to continue.  相似文献   

17.
The T7 antirestriction protein Ocr, encoded by 0.3 (ocr), specifically inhibits ATP-dependent type I restriction-modification systems. T7 0.3 (ocr) was cloned in pUC18. Ocr inhibited both restriction and modification activities of the type I restriction-modification system (EcoKI) in Escherichia coli K12. The Ocr F53D A57E mutant was obtained and proved to inhibit only restriction activity of EcoKI. The 0.3 (ocr) and Photorhabdus luminescens luxCDABE genes were cloned in pZ-series vectors with the P ltetO-1 promoter, strongly controlled by the TetR repressor. The bioluminescence intensity and luciferase content varied up to 5000-fold in E. coli K12 MG1655Z1 tetR+ (pZE21-luxCDABE) cells, depending on the environmental concentration of the inductor anhydrotetracycline. The antirestriction activity of Ocr and Ocr F53D A57E was studied as a function of their concentration in the cell. The dissociation constant K d, characterizing the binding with EcoKI, differed 1000-fold between Ocr and Ocr F53D A57E (10?10 M versus 10?7 M).  相似文献   

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19.
The patterns of the growth and oxidation of different types of natural pyrites were studied for the three microbial species adapted to these substrates and belonging to phylogenetically remote groups: gram-negative bacterium Acidithiobacillus ferrooxidans, gram-positive bacterium Sulfobacillus thermotolerans, and the archaeon Ferroplasma acidiphilum. For both A. ferrooxidans strains, TFV-1 and TFBk, pyrite 4 appeared to be the most difficult to oxidize and grow; pyrite 5 was oxidized by both strains at an average rate, and pyrite 3 was the most readily oxidized. On each of the three pyrites, growth and oxidation by TFBk were more active than by TFV-1. The effectiveness of the adaptation of S. thermotolerans Kr1T was low compared to the A. ferrooxidans strains; however, the adapted strain Kr1T showed the highest growth rate on pyrite 3 among all the cultures studied. No adaptation of strain Kr1T to pyrite 5 was observed; the rates of growth and pyrite oxidation in the third transfer were lower than in the first transfer. The strain F. acidiphilum YT was not adapted to pyrites 3 and 5; the rates of growth and pyrite oxidation were the same in the first five transfers. The strains of three species of the microorganisms studied, A. ferrooxidans, S. thermotolerans, and F. acidiphilum, grew on pyrite 3 (holetype (p) conductivity) and oxidized it better than pyrite 5 (mixed-type (n-p) conductivity). The most readily oxidized were the pyrites with a density of 5.6–5.7 g/cm3 and high resistance values (ln R = 8.8). The pyrite oxidation rate did not depend on the type of conductivity. Changes in the chromosomal DNA structure were revealed in strain TFBk on adaptation to pyrites 3 and 4 and in the TFV-1 plasmid profile on adaptation to pyrite 3. Correlation between genetic variability and adaptive capabilities was shown for A. ferrooxidans. No changes in the chromosomal DNA structure were found in S. thermotolerans Kr1T and F. acidiphilum YT on adaptation to pyrites 3 and 5. Plasmids were absent in the cells of these cultures.  相似文献   

20.
L-Lactate cytochrome c oxidoreductase (flavocytochrome b 2, FC b 2) from the thermotolerant methylotrophic yeast Hansenula polymorpha (Pichia angusta) is, unlike the enzyme form baker’s yeast, a thermostable enzyme potentially important for bioanalytical technologies for highly selective assays of L-lactate in biological fluids and foods. This paper describes the construction of flavocytochrome b 2 producers with over-expression of the H. polymorpha CYB2 gene, encoding FC b 2. The HpCYB2 gene under the control of the strong H. polymorpha alcohol oxidase promoter in a plasmid for multicopy integration was transformed into the recipient strain H. polymorpha C-105 (grc1 catX), impaired in glucose repression and devoid of catalase activity. A method was developed for preliminary screening of the transformants with increased FC b 2 activity in permeabilized yeast cells. The optimal cultivation conditions providing for the maximal yield of the target enzyme were found. The constructed strain is a promising FC b 2 producer characterized by a sixfold increased (to 3 μmol min?1 mg?1 protein in cell-free extract) activity of the enzyme.  相似文献   

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