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1.
Twenty-two zoosporic fungi were recovered from soil samples collected in Tunisia and in the Seychelles Islands in the Indian Ocean. One, Phlyctochytrium chandlerii is described as new. Most of the others are referred, sometimes tentatively, to existing species or genera.  相似文献   

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3.
Macvicaria obovata (Molin) n. comb. is redescribed from Sparus aurata off the Mediterranean coast of France and a neotype is designated. Specimens from Oblada melanura off Israel may belong to the same species. It is mainly characterized by the uterine extension between the ovary and the anterior testis and the lack of a vitelline confluence in the forebody. M. maillardi n. sp. is also described from Sparus aurata off the southern coast of France. Its uterus does not pass between ovary and testes and the vitelline fields are confluent in the forebody. M. crassigula (Linton) n. comb. is redescribed from Diplodus annularis, D. sargus, D. vulgaris, Pagellus erythrinus and Sparus pagrus off Corsica, Calamus bajonado off Bermuda, Spicara smaris, D. annularis off Yugoslavia, D. sargus off Israel, and D. cervinus, Sparodon durbanensis and Cheilodactylus fasciatus in the SW Indian Ocean. It is similar to M. maillardi, but differs in being smaller, having a greater sucker ratio and a larger pharynx. It may well be a species-complex. M. dubia (Stossich) n. comb. is redescribed from Oblada melanura off Corsica and Yugoslavia. It is similar to M. maillardi and M. crassigula, but has a more anteriorly situated genital pore.  相似文献   

4.
A Gram-positive, rod-shaped bacterium, designated strain SCSIO N0306T, was isolated from an abyssal sediment sample collected from the Indian Ocean. The isolate was found to grow optimally at 0–2 % (w/v) NaCl, pH 7.0 and 30 °C. Comparative analysis of the 16S rRNA gene sequence showed that the isolate SCSIO N0306T belongs phylogenetically to the genus Paenibacillus, and to be most closely related to P. algorifonticola XJ259T (with 95.47 % sequence similarity), sharing less than 95.0 % sequence similarity with all other taxa of this genus. Chemotaxonomic analysis revealed MK-7 as the major isoprenoid quinone, the DNA G+C content was determined to be 45.5 mol%, and anteiso-C15:0, C16:0, and iso-C15:0 were identified as the major fatty acids. On the basis of this polyphasic taxonomic data, isolate SCSIO N0306T is considered to represent a novel species of the genus Paenibacillus, for which the name Paenibacillus abyssi sp. nov. is proposed. The type strain is SCSIO N0306T (= DSM 26238T = CGMCC 1.12987T).  相似文献   

5.
Between 1966 and 1978 SCUBA investigations were carried out in French Polynesia, the Red Sea, and the Caribbean, at depths down to 70 m. Although there are fewer coral species in the Caribbean, the abundance of Scleractinia in deep-water associations below 20 m almost equals that in the Indian and Pacific Oceans. The assemblages of corals living there are described and defined as deep-water coral associations. They are characterized by large, flattened growth forms. Only 6 to 7 % of the species occur exclusively below 20 m. More than 90 % of the corals recorded in deep waters also live in shallow regions. Depth-related illumination is not responsible for depth differentiations of coral associations, but very likely, a complex of mechanical factors, such as hydrodynamic conditions, substrate conditions, sedimentation etc. However, light intensity determines the general distribution of hermatypic Scleractinia in their bathymetric range as well as the platelike shape of coral colonies characteristic for deep water associations. Depending on mechanical factors,Leptoseris, Montipora, Porites andPachyseris dominate as characteristic genera in the Central Pacific Ocean,Podabacia, Leptoseris, Pachyseris andCoscinarea in the Red Sea,Agaricia andLeptoseris in the tropical western Atlantic Ocean.  相似文献   

6.
The caprellid Caprella scaura, native to the western Indian Ocean, is one striking example of a successful invader. It was first recorded in the Iberian Peninsula in Gerona (north-eastern coast of Spain), in 2005, and has recently been reported throughout the Mediterranean and Atlantic coasts of this region. The most likely vector of introduction and distribution is within the hull-fouling community on recreational craft. However, beyond the dates of detection, the introduction history of C. scaura remains unclear. Direct sequencing of mitochondrial DNA (cytochrome c oxidase subunit I) was used to compare genetic composition in native and introduced populations in order to infer the invasion history of this species. In addition, 18S rDNA sequences were used to resolve phylogenetic relationships within this species and with the morphologically closest species Caprella californica and Caprella scauroides. The high genetic divergence and population subdivision found between non-native Iberian populations together with a high level of genetic diversity in some populations indicate multiple geographical sources and introduction points for this caprellid. Our data suggest that Iberian populations may derive from at least two sources: (1) Pacific Australian, and (2) Indian Ocean, either directly, or, more likely, through stepping-stone events from central Mediterranean population(s). Atlantic Iberian populations seem to be the most recently established populations. On the other hand, this is the first study providing molecular evidence confirming C. scaura, C. californica and C. scauroides as distinct species. It also provides strong molecular evidence that C. scaura typica and C. scaura scaura correspond to the same subspecies, and the Japanese C. scaura diceros and the Chilean C. scaura spinirostris could merit specific rank.  相似文献   

7.
A Gram-stain negative, oval-shaped, aerobic, catalase and oxidase-positive bacterium, designated JLT2014T, was isolated from a deep-seawater sample (obtained at a 2,000 m depth) of the Southeastern Pacific Ocean. The dominant fatty acids were identified as C18:1ω7c/C18:1ω6c, C16:0 and C10:0 3-OH, which altogether represented 60.1 % of the total. The predominant respiratory quinone was identified as Q-10. The G+C content of genomic DNA was determined to be 66.4 mol %. The major polar lipids were identified as phosphatidylethanolamine and diphosphatidylglycerol. Phylogenetic analysis based on the 16S rRNA gene sequence revealed that the novel isolate can be affiliated with the Roseobacter clade within the family Rhodobacteraceae. Strain JLT2014T exhibited highest 16S rRNA gene sequence similarity value to Pelagibaca bermudensis HTCC2601T (sequence similarity value: 97.6 %). The DNA–DNA relatedness value between strain JLT2014T and P. bermudensis HTCC2601T was 46.9 ± 2 %. Based on phenotypic properties and phylogenetic analysis, the name Pelagibaca abyssi sp. nov. is proposed, with JLT2014T(=LMG 27363T=CGMCC 1.12376T) as the type strain.  相似文献   

8.
The OsGS3 gene plays a principal role in controlling grain weight and grain length in rice. However, the function of an orthologous gene TaGS in wheat has not been analyzed to date. In the present study, we cloned the gDNA of TaGS gene, designated TaGS-D1, with four exons and three introns on chromosome 7DS by a comparative genomics approach. The cDNA of TaGS-D1 is 255 bp, and it encodes 85 amino acids. We also found a plant-specific organ size regulation domain in the deduced polypeptide, indicating that TaGS-D1, like OsGS3, does not belong to the PEBP family. DNA sequencing of the TaGS-D1 locus revealed no diversity in the coding sequence of exons, but there was a single nucleotide polymorphism (SNP) in the first intron, and 30 SNPs, a 40-bp InDel and a 3-bp InDel were found in the second intron between genotypes with higher and lower thousand grain weights (TGW). Based on the 40-bp InDel, a co-dominant STS marker, designated GS7D, was developed to discriminate the two alleles. GS7D was 8.0 cM from Xbarc184 located on chromosome 7DS by linkage mapping. A QTL for TGW and grain length at GS7D locus explained up to 16.3 and 7.7 %, respectively, of the phenotypic variances in a RIL population derived from Doumai/Shi 4185 grown in Shijiazhuang and Beijing. One hundred and seventy-five Chinese wheat cultivars were genotyped with GS7D, indicating that TaGS-D1 was significantly associated with grain weight. The allelic distribution at the TaGS-D1 locus showed that the frequencies of TaGS-D1a were high in cultivars from Serbia, Japan, Australia, Canada, and the Northeastern Spring Wheat and Northern Winter Wheat Regions of China.  相似文献   

9.
Tick-borne encephalitis virus (TBEV) (Flaviviridae, Flavivirus) is an arthropod-borne virus, an etiologic agent of tick-borne encephalitis (TBE), a human infection involving the central nervous system. The disease is endemic in a large region in Eurasia, where it is transmitted mainly by Ixodes ricinus and Ixodes persulcatus ticks. It is known that also Dermacentor reticulatus is involved in circulation of TBEV. However, the current knowledge of D. reticulatus importance in TBE epidemiology is still insufficient. A total of 471 adult D. reticulatus ticks were collected by flagging vegetation in the Bia?owie?a Primeval Forest, Biebrza National Park, Masurian Landscape Park (North-Eastern Poland) and in the city of Warsaw in the years 2007–2010. All collected ticks were examined individually for the presence of RNA of TBEV using nested RT-PCR assay. Positive results were noted in all investigated localities with the infection rate ranging from 0.99 to 12.5 % with a total mean of 2.12 %. The difference in the percentage of infective males and females was not statistically significant.  相似文献   

10.
The remains of carbonized plants recovered from sites destroyed by Mount Vesuvius in A.D. 79 furnish valuable historical evidence on many staple food plants used by the ancient Campanians of the 1st century A.D. Carbonized seeds,grains, nuts, and fruits of 24 species identified from documented materials at Pompeii, Herculaneum, and the Roman villa at Torre Annunziata include: filbert, Corylus avellana;broadbean, Vicia fabavar. minor;bittervetch. Vicia ervilia;chickpea, Cicer arietinum;carob, Ceratonia siliqua;lentil, Lens culinaris;European chestnut, Castanea sativa;English or Persian walnut, Juglans regia;common onion, Allium cepa;garlic, Allium sativum;fig, Ficus carica;olive, Olea europaea;date, Phoenix dactylifera;stone pine, Pinus pinea;six-rowed barley, Hordeum vulgare;emmer wheat, Triticum dicoccon;common millet, Panicum miliaceum;Italian millet, Setaria italica;oat, Avena sativa;almond, Prunus dulcis;sour cherry, Prunus cerasus;pear, Pyrus communis;crabapple, Malussp.;and grape, Vitis vinifera.  相似文献   

11.
Dendropoma maximum is a vermetid gastropod (a sessile tube-forming snail) commonly associated with living corals throughout shallow-water reefs of the Indo-Pacific. Recent work suggests that, once established, this species can adversely affect growth and survival of corals. Here, we test the hypotheses that disturbances to live coral substrates (e.g., creation of bare patches) facilitate successful larval settlement and subsequent population growth of D. maximum, and conversely, that live coral inhibits D. maximum settlement. In the shallow lagoon of Moorea, French Polynesia, we selected patch reefs where D. maximum was either present or absent (to evaluate potential effects of resident adult conspecifics on recruitment) and established focal quadrats on each reef. In each quadrat, we either experimentally removed 50 % of live coral cover or left the quadrat with 100 % live coral cover. In addition, we deployed units of bare substrate (coral rubble) to each reef. We conducted a census of deployed substrates and quadrats after 6 months and found that D. maximum settled irrespective of resident vermetid populations, and only onto nonliving surfaces (i.e., cleared patches in quadrats, coral rubble, and marine epoxy). In laboratory experiments, we exposed larvae of D. maximum to live coral and found species-specific effects on survival of D. maximum larvae. Porites lobata and Pocillopora sp. killed larvae of D. maximum, Porites rus caused weaker mortality, and Millepora sp. had no effect on larval survival. Collectively, these results suggest that D. maximum requires disturbances that create bare patches to successfully settle onto reefs, and that a high cover of living corals contributes resilience to reefs by limiting settlement opportunities of a species known to reduce coral growth and survival.  相似文献   

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13.
Ralstonia paucula strain RA4T, a gram negative, non-spore forming, motile bacterium having positive catalase and oxidase test, was isolated from surface soil. Twin arginine translocation protein type D (TatD) is shown to be located in cytoplasm and exhibits magnesium-dependent DNase. A tatD DNase gene was isolated and cloned from Ralstonia paucula RA4T genome. Nucleotide sequence analysis of the gene revealed 813 nucleotides encoding a protein of 270 amino acid residues. The tatD gene showed a high similarity to homolog gene from Ralstonia pickettii strain 12D. The deduced polypeptide sequence of TatD DNase from R. paucula RA4T had a typical catalytic site, HHPLDEHRHDP, and its calculated molecular mass and predicted isoelectric point were 29616 Da and 5.33, respectively. The deduced amino acid sequence showed a high degree of similarity to TatD DNase isoforms from Ralstonia genus and other sources. Predicted three-dimensional structure of TatD confirmed the presence of active site and theoretical function as DNase.  相似文献   

14.
Argininosuccinate synthase (Ass) and argininosuccinate lyase (Asl) are involved in arginine synthesis for various purposes. The complete cDNA coding sequences of ass and asl from the liver of Protopterus annectens consisted of 1,296 and 1,398 bp, respectively. Phylogenetic analyses revealed that the deduced Ass and Asl of P. annectens had close relationship with that of the cartilaginous fish Callorhinchus milii. Besides being strongly expressed in the liver, ass and asl expression were detectable in many tissues/organs. In the liver, mRNA expression levels of ass and asl increased significantly during the induction phase of aestivation, probably to increase arginine production to support increased urea synthesis. The increases in ass and asl mRNA expression levels during the prolonged maintenance phase and early arousal phase of aestivation could reflect increased demand on arginine for nitric oxide (NO) production in the liver. In the kidney, there was a significant decrease in ass mRNA expression level after 6 months of aestivation, indicating possible decreases in the synthesis and supply of arginine to other tissues/organs. In the brain, changes in ass and asl mRNA expression levels during the three phases of aestivation could be related to the supply of arginine for NO synthesis in response to conditions that resemble ischaemia and ischaemia–reperfusion during the maintenance and arousal phase of aestivation, respectively. The decrease in ass mRNA expression level, accompanied with decreases in the concentrations of arginine and NO, in the skeletal muscle of aestivating P. annectens might ameliorate the potential of disuse muscle atrophy.  相似文献   

15.
Increased atmospheric CO2 will have a twofold impact on future marine ecosystems, increasing global sea surface temperatures and uptake of CO2 (Ocean Acidification). Many experiments focus on the investigation of one of these stressors, but under realistic future climate predictions, these stressors may have interactive effects on individuals. Here, we investigate the effect of warming and acidification in combination. We test for interactive effects of potential near-future (2100) temperature (+2 to 3 °C) and pCO2 (~860–940 μAtm) levels on the physiology of the tropical echinoid Echinometra sp. A. The greatest reduction in growth was under simultaneous temperature and pH/pCO2 stress (marginally significant temperature × pH/pCO2 interaction). This was mirrored by the physiological data, with highest metabolic activity (measured as respiration and ammonium excretion) occurring at the increased temperature and pCO2 treatment, although this was not significant for excretion. The perivisceral coelomic fluid pH was ~7.5–7.6, as typical for echinoids, and showed no significant changes between treatments. Indicative of active calcification, internal magnesium and calcium concentrations were reduced compared to the external medium, but were not different between treatments. Gonad weight was lower at the higher temperature, and this difference was more distinct and statistically significant for males. The condition of the gonads assessed by histology declined in increased temperature and low pH treatments. The Echinometra grew in all treatments indicating active calcification of their magnesium calcite tests even as carbonate mineral saturation decreased. Our results indicate that the interactive temperature and pH effects are more important for adult echinoids than individual stressors. Although adult specimens grow and survive in near-future conditions, higher energy demands may influence gonad development and thus population maintenance.  相似文献   

16.
RelA and SpoT synthesize ppGpp, a key effector molecule that facilitates the adaptation of bacteria to nutrient starvation and other stresses, known as the stringent response. To investigate the role of Rsh Bant , a putative RelA/SpoT homolog (encoded by BAS4302) in Bacillus anthracis, we examined the alteration of the secretome profiles after the overexpression of a functional His-Rsh Bant protein in the B. anthracis strain Sterne at the stationary growth phase. In the ppGpp-deficient E. coli mutant strain CF1693, overexpression of Rsh Bant restored a ppGpp-dependent growth defect on minimal glucose media. The secretome profiles obtained using a two-dimensional electrophoresis (2-DE) analysis were altered by overexpression of Rsh Bant in B. anthracis. Among the 66 protein spots differentially expressed >1.5-fold, the 29 proteins were abundant for further identification using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). Functional categorization of those proteins implicated their involvement in various biological activities. Taken together, our results imply that overexpression of a functional His-Rsh Bant can lead to the increased levels of intracellular ppGpp in B. anthracis, resulting in the significant changes in its secretome profiling. The stringent response-controlled proteins identified are likely useful as potential targets for serodiagnostic applications.  相似文献   

17.
Buller’s Albatross, Thalassarche bulleri, is a New Zealand breeding endemic that is frequently observed in the subtropical and sub-Antarctic South Pacific Ocean between Australia and Peru. However, in the South Atlantic Ocean, it is a vagrant, as information on its presence in this region is limited to only a few sightings. Here, we report a new record of T. bulleri in the south-western Atlantic Ocean off Argentina (55°06′13″S, 66°06′44″W) while investigating interactions between commercial fisheries and seabirds. This record provides new information about the distribution of this albatross species and its relation with fisheries outside of its regular range.  相似文献   

18.
A taxonomic study was carried out on strain 13D2W-2T, which was isolated from a sulphur-oxidizing bacterial consortium, enriched by the deep-sea sediment of the Atlantic Ocean. The isolate was observed to be Gram-negative, oxidase- and catalase-positive, short rod-shaped and motile by means of a flagellum. Growth was observed at salinities from 0.5 to 12 % and at temperatures from 4 to 41 °C, and the strain found to be able to reduce nitrate but not degrade gelatin. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain 13D2W-2T belongs to the genus Thioclava, with highest sequence similarity of 97.8 % to Thioclava dalianensis DLFJ1-1T, followed by Thioclava pacifica TL 2T (97.7 %), while the sequence similarities to other members of the genus were all below 97.0 %. The digital DNA:DNA hybridization estimated values between strain 13D2W-2T and, respectively, T. dalianensis DLFJ1-1T and T. pacifica TL 2T were 22.6 ± 2.4 and 25.6 ± 2.4 %. The ANI values between strain 13D2W-2T and T. dalianensis DLFJ1-1T and T. pacifica TL 2T were 78.49 and 81.91 % respectively. The principal fatty acid identified was Summed Feature 8 (C18:1 ω7c/ω6c) (74.38 %). The isoprenoid quinone of strain 13D2W-2T was identified as Q10 (100 %). The major polar lipids of strain 13D2W-2T were found to be comprised of phosphatidylethanolamine, phosphatidylglycerol, an aminophospholipid, a glycolipid and three unknown phospholipids. The G+C content of the chromosomal DNA was determined to be 65.3 mol%. The combined genotypic and phenotypic data show that strain 13D2W-2T represents a novel species of the genus Thioclava, for which the name Thioclava atlantica sp. nov. is proposed, with the type strain 13D2W-2T ( = MCCC 1A02612T = LMG 27145T).  相似文献   

19.
In this paper, we present the results of a comparative genetic and ultrastructural study of three clones of the microalga Porphyridium purpureum (Rhodophyta) from the culture collection of marine microalgae of the Zhirmunsky Institute of Marine Biology. All clones, which have different geographical origins, showed a high similarity in terms of the ultramicroscopic structure and the nucleotide sequences of the nuclear ribosomal DNA genes (18S rDNA, ITS1-5.8S rDNA-ITS2, D1-D2 region of 28S rDNA). The obtained data are very helpful for the certification of two strains of P. purpureum that were isolated for the first time in the practice of Russian algological research.  相似文献   

20.
The zona pellucida 3 (ZP3) plays a crucial role in reproductive immunology. We obtained a full-length cDNA encoding Chinese zokor ZP3, using rapid amplification of cDNA ends-polymerase chain reaction (RACE-PCR). The cDNA contains an open reading frame of 1269 nucleotides encoding a polypeptide of 422 amino acid residues. The amino acid sequence has a high degree of homology with those of hamster (78%), mouse (76%), and rat (74%). XhoI and SacI sites after restriction give an1158 bp fragment of zokor ZP3 cDNA, excluding the signal sequence and transmembrane-like domain, which was cloned under the phage T7 promoter-lac operator control in the pET-28a(+) vector. Recombinant pET-zokorZP3(r-ZP3) was expressed as a poly-histidine fusion protein in E. coli strain BL21 (DE3). Optimum expression of r-ZP3 was observed at 28°C, 1 mM IPTG and 2 h of inducing. The purified protein was tested by Western blot.  相似文献   

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