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1.
Previous analysis of the Continuous Plankton Recorder (CPR) long-term data set for the presence of ‘coelenterate’ tissue revealed changes in the frequency of jellyfish occurrence in the North Atlantic Ocean and North Sea; however, the identities of the jellyfish were unknown, causing uncertainty in interpreting these findings. To improve the utility of the ‘coelenterate’ data from the CPR, 62 CPR samples were selected for re-analysis from an area where the widespread occurrence of the holoplanktonic scyphomedusan, Pelagia noctiluca (Forsskål, 1775), was previously documented from net tows to test if the CPR sampled P. noctiluca. Examination of the samples revealed smears (<1 mm) of golden gelatinous tissue on the sampling mesh. Subsequent microscopic examination and measurement of nematocysts identified most of the smears as P. noctiluca. Indeed, P. noctiluca was identified on 53% of the CPR samples from the area that best coincided with the documented bloom area. Although hydrozoans were also identified in the samples, the characteristic golden colour of P. noctiluca and its distinct suite of nematocysts allowed identification to species level. The identification of other jellyfish may be more complicated due to the labour-intensive examination of samples and unclear delineation of nematocyst types when multiple similar species are present. Nevertheless, re-analysis of CPR samples holds great promise for identifying the underlying reason for increases in jellyfish occurrence in the CPR records.  相似文献   

2.
Although many fish species are known to feed on jellyfish, only a few quantitative studies on this subject have been conducted in the field or laboratory. We combined field observations and feeding experiments to quantitatively evaluate the potential feeding capability of the black scraper Thamnaconus modestus on giant jellyfish Nemopilema nomurai in a jellyfish-abundant area. Underwater observations revealed that shoals of T. modestus fed voraciously on jellyfish when the jellyfish were close to the fish’s seaweed habitat. Gut contents of field-collected T. modestus almost exclusively consisted of jellyfish. In tank trials, feeding activity of black scraper was high when light intensity was between about 1.1 lx and 50 × 103 lx. The estimated feeding speed of T. modestus on the jellyfish in the Sea of Japan when the jellyfish bloom occurred was 10.0 ± 2.0 times fish body weight per day. The results support the prediction that T. modestus and probably other coastal medusivorous fishes have a substantial capability to eliminate jellyfish blooms. Considering that they are highly dependent on seaweed bed, protection of such habitats for these medusivores may be the most cost-efficient control method for jellyfish blooms.  相似文献   

3.
Myzus persicae (Sulzer) is a polyphagous aphid that causes chlorosis, necrosis, stunting, and reduce growth rate of the host plants. In this research, the effects of Zinc sulfate and vermicompost (30%), Bacillus subtilis, Pseudomonas fluorescens, Glomus intraradices, G. intraradices × B. subtilis, and G. intraradices × P. fluorescens compared to control was investigated on the growth characters of Capsicum annuum L. and biological parameters of M. persicae. Different fertilizers caused a significant effect on growth characters of C. annuum and biological parameters of M. persicae. The highest plant growth was observed on Zinc sulfate and B. subtilis treated plants, and the lowest was on control. Increase in the amount of specific leaf area (SLA) (0.502 mm2 mg?1) was significantly higher in the B. subtilis than other fertilizer treatments. The longest (10.3 days) and the shortest (5.3 days) developmental times of M. persicae nymphs were observed on 30% vermicompost and Zinc sulfate treatments, respectively. The lowest adult longevity periods of M. persicae (11.2 and 11.3 days) were observed on G. intraradices × B. subtilis and 30% vermicompost treatments, respectively, and the longest ones (16.4 days) on Zinc sulfate. The highest rate of nymphal mortality and the lowest amount of nymphal growth index (NGI) were recorded on 30% vermicompost. The nymphs reared on Zinc sulfate treatment had the lowest rate of nymphal mortality and the highest amount of NGI. Thus, amending the soil with 30% vermicompost had a significantly negative effect on the biological parameters of M. persicae that can be used as an ecological control tactic for this pest.  相似文献   

4.
Trace elements such as Zinc and Iron are essential components of metalloproteins and serve as cofactors or structural elements for enzymes involved in several important biological processes in almost all organisms. Because either excess or insufficient levels of Zn and Fe can be harmful for the cells, the homeostatic levels of these trace minerals must be tightly regulated. The Zinc regulated transporter, Iron regulated transporter-like Proteins (ZIP) comprise a diverse family, with several paralogues in diverse organisms and are considered essential for the Zn and Fe uptake and homeostasis. Zn and Fe has been shown to regulate expression of proteins involved in metabolism and pathogenicity mechanisms in the protozoan pathogen Trichomonas vaginalis, in contrast high concentrations of these elements were also found to be toxic for T. vaginalis trophozoites. Nevertheless, Zn and Fe uptake and homeostasis mechanisms is not yet clear in this parasite. We performed a genome-wide analysis and localized the 8 members of the ZIP gene family in T. vaginalis (TvZIP1-8). The bioinformatic programs predicted that the TvZIP proteins are highly conserved and show similar properties to the reported in other ZIP orthologues. The expression patterns of TvZIP1, 3, 5 and 7 were diminished in presence of Zinc, while the rest of the TvZIP genes showed an unchanged profile in this condition. In addition, TvZIP2 and TvZIP4 showed a differential expression pattern in trophozoites growth under different Iron conditions. These results suggest that TvZIP genes encode membrane transporters that may be responsible for the Zn and Fe acquisition in T. vaginalis.  相似文献   

5.
Prevotella is part of the oral bacterial community implicated in periodontitis. Pan genome analyses of eight oral Prevotella species, P. dentalis, P. enoeca, P. fusca, P. melaninogenica, P. denticola, P. intermedia 17, P. intermedia 17-2 and P. sp. oral taxon 299 are presented in this study. Analysis of the Prevotella pan genome revealed features such as secretion systems, resistance to oxidative stress and clustered regularly interspaced short palindromic repeat (CRISPR)-Cas systems that enable the bacteria to adapt to the oral environment. We identified the presence of type VI secretion system (T6SS) in P. fusca and P. intermedia strains. For some VgrG and Hcp proteins which were not part of the core T6SS loci, we used gene neighborhood analysis and identified putative effector proteins and putative polyimmunity loci in P. fusca and polymorphic toxin systems in P. intermedia strains. Earlier studies have identified the presence of Por secretion system (PorSS) in P. gingivalis, P. melaninogenica and P. intermedia. We noted the presence of their homologs in six other oral Prevotella studied here. We suggest that in Prevotella, PorSS is used to secrete cysteine proteases such as interpain and C-terminal domain containing proteins with a “Por_secre_tail” domain. We identified subtype I-B CRISPR-Cas system in P. enoeca. Putative CRISPR-Cas system subtypes for 37 oral Prevotella and 30 non-oral Prevotella species were also predicted. Further, we performed a BLASTp search of the Prevotella proteins which are also conserved in the red-complex pathogens, against the human proteome to identify potential broad-spectrum drug targets. In summary, the use of a pan genome approach enabled identification of secretion systems and defense mechanisms in Prevotella that confer adaptation to the oral cavity.  相似文献   

6.
In vitro growth, development, total soluble proteins and peroxidase profiles of Salvadora oleoides and Salvadora persica under NaCl stress were analysed in the present investigation. The plants are evergreen haloxeric tree species of family Salvadoraceae. Shoot apex from natural plants were initially used for screening of NaCl tolerance on MS culture medium. Shoot apex of S. oleoides and S. persica could survive optimally up to 200 and 100 mM NaCl. Axillary buds from nodal shoot segments of S. oleoides and S. persica were activated on 6 and 4 μM BAP, and were used further for extraction of total soluble proteins and peroxidases. Total soluble proteins were increased up to 150 mM NaCl in S. oleoides, but decline above 50 mM NaCl in S. persica. Peroxidase activity remained almost constant in S. oleoides at all the concentrations and duration of NaCl, but increased at 100 mM NaCl during fourth week of treatment in S. persica. Eleven peroxidase isozymes were observed in zymogram of S. oleoides. Isozymes P1, P2, P3, and P4 were slightly appeared, but P6 isozyme was lacking in S. persica. The P5 isozyme was more prominent in S. persica than S. oleoides. Isozyme P9 of S. persica was visible during the first week of NaCl treatment, but disappeared in the fourth week. Molecular biology of these plants can be useful further for the understanding of stress tolerance mechanisms for prospects.  相似文献   

7.
8.
A comparative proteomic approach was performed to analyze the differential accumulation of leaf proteins in response to the symbiosis between Solanum lycopersicum and the arbuscular mycorrhizal fungus (AMF) Rhizophagus irregularis. Protein profiling was examined in leaves from tomato plants colonized with AMF (M), as well as non-colonized plants fertilized with low phosphate (20 μM P; NM-LP) and non-colonized plants fertilized with regular phosphate Hoagland’s solution (200 μM P; NM-RP). Comparisons were made between these groups, and 2D-SDS-PAGE revealed that 27 spots were differentially accumulated in M vs. NM-LP. Twenty-three out of the 27 spots were successfully identified by mass spectrometry. Two of these proteins, 2-methylene-furan-3-one reductase and auxin-binding protein ABP19a, were up-accumulated in M plants. The down-accumulated proteins in M plants were associated mainly with photosynthesis, redox, and other molecular functions. Superoxide dismutase, harpin binding protein, and thioredoxin peroxidase were down-accumulated in leaves of M tomato plants when compared to NM-LP and NM-RP, indicating that these proteins are responsive to AMF colonization independently of the phosphate regime under which they were grown. 14-3-3 protein was up-accumulated in NM-RP vs. NM-LP plants, whereas it was down-accumulated in M vs. NM-LP and M vs. NM-RP, regardless of their phosphate nutrition. This suggests a possible regulation by P nutrition and AMF colonization. Our results demonstrate AMF-induced systemic changes in the expression of tomato leaf proteins, including the down-accumulation of proteins related to photosynthesis and redox function.  相似文献   

9.
In coastal areas with a high intensity of human activities, expansion of artificial structures may enhance Aurelia spp. blooms because these constructions may provide additional substrates for the settlement and proliferation of the polyps. In the present study, the possible occurrence and distribution of Aurelia coerulea ephyrae and polyps were investigated in sea cucumber (Apostichopus japonicus) culture ponds that contain huge amounts of artificial structures. Our results showed that A. coerulea ephyrae were widely distributed in the A. japonicus culture ponds along the Bohai and Yellow Seas. Furthermore, underwater photography revealed that polyps of A. coerulea mainly occurred on the undersides of the artificial reefs made by plastic sunshade nets, tiles and substrate cages. The artificial reefs may decrease the time A. coerulea planulae spend settling, provide more hidden, calm and shady places for the settlement and proliferation of A. coerulea planulae, and thus were suitable substrates for the moon jellyfish A. coerulea. Our study suggests that the A. japonicus culture ponds may act as nursery grounds for the jellyfish A. coerulea and may potentially enhance the blooms of this species in the coastal waters along the Bohai and Yellow Seas.  相似文献   

10.
11.

Background

Post-translational modifications (PTMs) constitute a huge group of chemical modifications increasing the complexity of the proteomes of living beings. PTMs have been discussed as potential anti-malarial drug targets due to their involvement in many cell processes. O-GlcNAcylation is a widespread PTM found in different organisms including Plasmodium falciparum. The aim of this study was to identify O-GlcNAcylated proteins of P. falciparum, to learn more about the modification process and to understand its eventual functions in the Apicomplexans.

Methods

The P. falciparum strain 3D7 was amplified in erythrocytes and purified. The proteome was checked for O-GlcNAcylation using different methods. The level of UDP-GlcNAc, the donor of the sugar moiety for O-GlcNAcylation processes, was measured using high-pH anion exchange chromatography. O-GlcNAcylated proteins were enriched and purified utilizing either click chemistry labelling or adsorption on succinyl-wheat germ agglutinin beads. Proteins were then identified by mass-spectrometry (nano-LC MS/MS).

Results

While low when compared to MRC5 control cells, P. falciparum disposes of its own pool of UDP-GlcNAc. By using proteomics methods, 13 O-GlcNAcylated proteins were unambiguously identified (11 by click-chemistry and 6 by sWGA-beads enrichment; 4 being identified by the 2 approaches) in late trophozoites. These proteins are all part of pathways, functions and structures important for the parasite survival. By probing clicked-proteins with specific antibodies, Hsp70 and α-tubulin were identified as P. falciparum O-GlcNAc-bearing proteins.

Conclusions

This study is the first report on the identity of P. falciparum O-GlcNAcylated proteins. While the parasite O-GlcNAcome seems close to those of other species, the structural differences exhibited by the proteomes provides a glimpse of innovative therapeutic paths to fight malaria. Blocking biosynthesis of UDP-GlcNAc in the parasites is another promising option to reduce Plasmodium life cycle.
  相似文献   

12.
Prunus fruticosa is a rare shrub occurring in Eurasian thermophilous forest-steppe alliances. The species frequently hybridizes with cultivated Prunus species in Europe (allochthonous tetraploid P. cerasus and partly indigenous diploid P. avium). Propidium iodide flow cytometry, distance-based morphometrics, elliptic Fourier analysis and embryology were employed to evaluate the extent of hybridization in six Slovak populations. Flow cytometric analyses revealed three ploidy levels: diploid (P. avium), triploid (P. × mohacsyana) and tetraploid (P. fruticosa, P. × eminens and P. cerasus). In addition, P. fruticosa and P. cerasus, at the tetraploid level, were found to differ in absolute genome size. An embryological evaluation suggested the existence of a triploid block in P. × mohacsyana and significant potential for hybridization among tetraploid taxa (indicated also by a continuous distribution of genome size data and further mirrored by morphometrics). Although hybrids significantly differ in ploidy level and embryological characteristics, they are almost indistinguishable using morphological characters. Hybridization with P. cerasus thus turns out to be a significant threat to wild populations of P. fruticosa compared to the relatively weak influence of P. avium.  相似文献   

13.
Although the Arctic cod (Boreogadus saida) has a pan-Arctic distribution, little is known about its occurrence in near-shore waters where this species is the principal prey for seabirds, marine mammals and other fish. Published research describes the scyphomedusa Cyanea capillata as an Arctic cod predator, and this paper presents observations from long-term investigations using active hydroacoustics that suggest the Arctic cod avoided C. capillata in two small bays of Cornwallis Island (Canadian High Arctic archipelago). Distribution patterns in echograms suggested that features such as boundary layer fronts restricted jellyfish movements and Arctic cod were often abundant on the side of fronts where C. capillata were absent. Thus, habitat partitioning allowed Arctic cod to share habitat with its predator, albeit exceptions to this sharing occurred when jellyfish abundance was high and Arctic cod were displaced. Thus, if a warmer Arctic triggers an increase in C. capillata abundance, it is possible that small-scale aspects of Arctic cod distribution could be affected. This in turn could have significant ripple effects within the Arctic food web, an additional and previously unrecognized consequence of climate change.  相似文献   

14.
Growth traits are complex quantitative traits controlled by numerous candidate genes, and they can be well-evaluated using body measurement traits. As the members of the nicotinamide adenine dinucleotide-dependent family of histone deacetylases, class I sirtuin genes (including SIRT1, SIRT2 and SIRT3) play crucial roles in regulating lipid metabolism, cellular growth and metabolism, suggesting that they are potential candidate genes affecting body measurement traits in animals. Hence, the objective of this work aimed to detect novel insertions/deletions (indels) of SIRT1, SIRT2 and SIRT3 genes in 955 cattle belonging to five breeds, as well as to evaluate their effects on body measurement traits. Herein, the novel 12-bp indel of SIRT1 gene, the 7-bp indel of SIRT2 gene and the 26-bp indel of SIRT3 gene were firstly reported, respectively. The association analysis indicated that the indels within SIRT1 and SIRT2 genes were significantly associated with body measurement traits such as body weight, chest circumference, height at hip cross, hip width, body height, etc. (P?<?0.05 or P?<?0.01). Therefore, based on these findings, the two novel indel variants within bovine SIRT1 and SIRT2 genes could be considered as potential molecular markers for growth traits in cattle selection practices and breeding.  相似文献   

15.

Objective

To construct efficient transformation and expression system and further improve desulfurizing activity of cells through expression of Vitreoscilla hemoglobin (VHb) in haloalkaliphilic Thialkalivibrio versutus SOB306.

Results

We transferred plasmids pKT230 and pBBR-smr into T. versutus SOB306 via a conjugation method. We identified four promoters from among several predicted promoters by scoring for streptomycin resistance, and finally selected tac and p3 based on the efficiency of expression of red fluorescent protein (RFP). Expression of RFP when regulated by tac was more than three times that of p3 in SOB306. Further, we expressed VHb under the control of tac promoter in SOB306. Expression of VHb was verified using CO-difference spectra. The results showed that VHb expression can boost sulfur metabolism, as evidenced by an increase of about 11.7 ± 1.8% in the average rate of thiosulfate removal in the presence of VHb.

Conclusion

A conjugation transfer and an expression system for Thialkalivibrio, has been developed for the first time and used for expression of VHb to improve desulfurizing activity.
  相似文献   

16.
Thaumatin-like proteins (TLPs) are pathogenesis-related proteins, which are involved in plant defense responses to pathogen infection. Expression of the Pinus sylvestris L. TLP gene is up-regulated by methyl jasmonate treatment and inoculation with Heterobasidion annosum. A full-length Pinus taeda TLP gene sequence was used to design PCR primers for amplification of the full-length TLP gene from P. sylvestris. A putative 705-bp open reading frame of TLP gene was cloned into Escherichia coli cells, and then subcloned into the overexpression vector pET100 using BL21 Star expression bacteria. Optimization of the expression of recombinant TLP was achieved by decreasing both expression temperature and IPTG concentration. The purified 24.6-kDa TLP shows antimicrobial activity against 12 fungal species.  相似文献   

17.
Stress-associated proteins (SAPs) are a novel class of zinc finger proteins that extensively participate in abiotic stress responses. To date, no overall analysis and expression profiling of SAP genes in woody plants have been reported. Populus euphratica is distributed in desert regions and is extraordinarily adaptable to abiotic stresses. Thus, it is regarded as a promising candidate for studying abiotic stress resistance mechanisms of woody plants. In this study, 18 non-redundant SAP genes were identified from the genome of P. euphratica using basic local alignment search tool algorithms and functional domain verification. Among these 18 PeuSAP genes, 15 were intronless. To investigate the evolutionary relationships of SAP genes in P. euphratica and other Salicaceae plants, phylogenetic analyses were performed. Subsequently, the expression profiles of the 18 PeuSAP genes were analyzed in different tissues and under various stresses (drought, salt, heat, cold, and abscisic acid (ABA) treatment) using quantitative real-time PCR. Tissue expression analysis indicated that PeuSAPs showed no tissue specificity. PeuSAPs were induced by multiple abiotic stresses, especially drought, salt, and heat stresses, perhaps because of abundant cis-acting heat shock elements and drought-inducible elements in the promoter regions of the PeuSAPs. Moreover, single nucleotide polymorphisms (SNPs) variant analysis revealed many synonymous and non-synonymous SNPs in PeuSAP genes, but the zinc finger structure was conserved during evolution. These results provide an overview of the SAP gene family in P. euphratica and a reference for further functional research on PeuSAP genes.  相似文献   

18.
The vulnerability of gastropods to their predators varies with life history traits such as morphology, body size, behavior, and growth rates as well as predator size. A recent study suggested that the invasive apple snail, Pomacea maculata, was considerably more vulnerable to crayfish predators than the native Florida apple snail, P. paludosa. The difference was hypothesized to be caused by the relatively small hatchling size of P. maculata. To test this hypothesis, we conducted a series of feeding assays designed to quantify maximum feeding rates and selective foraging of crayfish on apple snails. The rate at which crayfish killed individual P. maculata (i.e., kill rates) decreased with snail size, and kill rates on both species increased with crayfish size. Kill rates on juvenile P. maculata were higher than kill rates on size-matched hatchling P. paludosa, and crayfish fed selectively on P. maculata when offered mixed groups of size-matched snails. Further analyses revealed that hatchling P. paludosa possess shells 1.8× heavier than size-matched P. maculata suggesting differences in vulnerability to crayfish were consistent with interspecific differences in shell defenses. Differences in hatchling size and defensive traits in combination make crayfish kill rates on hatchling P. maculata approximately 15.4× faster than on hatchling P. paludosa, but the relative contribution of hatchling size to differences in apple snail vulnerability was >3× greater than the contribution of defensive traits.  相似文献   

19.
Phytocyanins (PCs) are ancient blue copper-binding proteins in plants that bind to single type I copper atoms and function as electron transporters. PCs play an important role in plant development and stress resistance. Many PCs are considered to be chimeric arabinogalactan proteins (AGPs). Previously, 38, 62, and 84 PC genes were identified in Arabidopsis thaliana, Oryza sativa, and Brassica rapa, respectively. In this study, we identified 30 putative PC genes in the orchid Phalaenopsis equestris through comprehensive bioinformatics analysis. Based on phylogeny and motif constitution, the P. equestris phytocyanins (PePCs) were divided into five subclasses: 10 early nodulin-like proteins, 10 uclacyanin-like proteins, five stellacyanin-like proteins, four plantacyanin-like proteins, and one unknown protein. Structural and glycosylation predictions suggested that 16 PePCs were glycosylphosphatidylinositol-anchored proteins localized to the plasma membrane, 22 PePCs contain N-glycosylation sites, and 14 are chimeric AGPs. Phylogenetic analysis indicated that each subfamily was derived from a common ancestor before the divergence of monocot and dicot lineages and that the expansion of the PC subfamilies occurred after the divergence of orchids and Arabidopsis. The number of exons in PC genes was conserved. Expression analysis in four tissues revealed that nine PC genes were highly expressed in flowers, stems, and roots, suggesting that these genes play important roles in growth and development in P. equestris. The results of this study lay the foundation for further analysis of the functions of this gene family in plants.  相似文献   

20.
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