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1.
Six new species Tagonoides belousovi sp. n., T. yunnana sp. n., Gnaptorina australis sp. n., Agnaptoria elongata sp. n. (Yunnan), A. lecta sp. n., and A. ruida sp. n. (Sichuan), and a new subspecies Gnaptorina potanini minxiana subsp. n. are described from China. Morphological adaptations of tenebrionids of the tribe Blaptini associated with phytophagous habit are discussed.  相似文献   

2.
In recent years, some marine microbes have been used to degrade diesel oil. However, the exact mechanisms underlying the biodegradation are still poorly understood. In this study, a hypothermophilous marine strain, which can degrade diesel oil in cold seawater was isolated from Antarctic floe-ice and identified and named as Rhodococcus sp. LH. To clarify the biodegradation mechanisms, a gas chromatography-mass spectrometry (GC-MS)-based metabolomics strategy was performed to determine the diesel biodegradation process-associated intracellular biochemical changes in Rhodococcus sp. LH cells. With the aid of partial least squares-discriminant analysis (PLS-DA), 17 differential metabolites with variable importance in the projection (VIP) value greater than 1 were identified. Results indicated that the biodegradation of diesel oil by Rhodococcus sp. LH was affected by many different factors. Rhodococcus sp. LH could degrade diesel oil through terminal or sub-terminal oxidation reactions, and might also possess the ability to degrade aromatic hydrocarbons. In addition, some surfactants, especially fatty acids, which were secreted by Rhodococcus into medium could also assist the strain in dispersing and absorbing diesel oil. Lack of nitrogen in the seawater would lead to nitrogen starvation, thereby restraining the amino acid circulation in Rhodococcus sp. LH. Moreover, nitrogen starvation could also promote the conversation of relative excess carbon source to storage materials, such as 1-monolinoleoylglycerol. These results would provide a comprehensive understanding about the complex mechanisms of diesel oil biodegradation by Rhodococcus sp. LH at the systematic level.  相似文献   

3.
Morphological investigations of motile cells and cysts of a small dinoflagellate (strain CCMP 2088) isolated from Canadian Arctic waters were carried out under both light and scanning electron microscopy. This species strongly resembled Polarella glacialis (strain CCMP 1383), which up to now was known only from Antarctic sea ice. The photosynthetic pigment composition of strain CCMP 2088 is typical of dinoflagellates, with peridinin as a major accessory pigment. Phylogenetic relationships between the two strains and other dinoflagellate species were inferred from SSU nrDNA using Neighbour Joining and weighted parsimony analyses. Our results showed that strain CCMP 2088 and P. glacialis (strain CCMP 1383) grouped in the same clade (Suessiales clade), showing high similarity values (0.99%). Morphological and molecular data support the assignment of the Arctic strain to P. glacialis. The free-living Gymnodinium simplex and the two P. glacialis strains have a basal position in the Suessiales clade, as compared to Symbiodinium spp.  相似文献   

4.
The bacterial diversity of the outflows of Polichnitos (Lesvos, Greece) hot spring has been investigated. Cyanobacteria showing high sequence homologies with Phormidium sp. and Cyanobacterium aponinum were found. Members of the Alphaproteobacteria closely related to Rhodobium sp. Albidovulum sp., Rhodobacter sp., Microvigra sp., Nitratireductor sp. and Phaeobacter sp. Gammaproteobacteria, Betaproteobacteria and Firmicutes were represented by members of Idiomarina sp., Marinobacter sp., Shinella sp., Bacillus sp. and Clostridium sp. with sequence homologies ranging from 92% to 100%. Members of the Bacteroidetes and Planctomycetes were represented by sequences of novel phylogenetic linkages exhibiting 87–90% sequence homology with type strains. When the hot spring consortium was cultivated in bioreactor repeated batch culture under photo-autotrophic growth conditions at temperature < 30 °C, Cyanobacterium sp. dominated over Phormidium sp. Cyanobacterium sp. seems to have biotechnological potential since its extracellular broth exhibited a strong insecticidal activity against larvae of Aedes aegypti (a vector of important human diseases) and significant anti-cancer activity against the PC3 human prostate cancer cell line, while its toxicity against human endothelial cells was relatively low.  相似文献   

5.
A strain of Bacillus amyloliquefaciens (VCRC B483) exhibiting mosquito pupicidal, keratinase and antimicrobial activities was isolated from mangrove forest ecosystem of Andaman and Nicobar Islands. Molecular characterization of the strain showed the presence of lipopeptide encoding bmyC gene. Phylogenetic tree based on protein sequence of this gene exhibited homology with mycosubtilin synthetase of Bacilus atropheus and Iturin synthetase of Bacillus subtilis and B. amyloliquefaciens. This is the first report on the evolutionary conservation of amino acids concerned with the function and structure of bmyC protein of B. amyloliquefaciens. The presence of valine at the 1197th position in our strain was found to be unique and different from the existing strains of B. subtilis and B. amyloliquefaciens. Molecular modelling studies revealed significant changes in the structure of epimerization domain of the bmyC protein with A1197V variation. Crude metabolite of this strain exhibited antifungal activity against Fusarium sp. and Carvularia sp.  相似文献   

6.
The resinous part called agarwood of genus Aquilaria Lam has been exploited as a source of incense by mankind since time immemorial besides its medicinal properties. In global market purest oud/agarwood oil enjoys an exorbitant price tag owing to its mystical fragrance. This has led to over-exploitation of Aquilaria sp. at worldwide level. All the Aquilaria sp. are protected under CITES since 2002. Agarwood production is considered to have a pathological relation, secreted actively in response to foreign body infection as a means of defense mechanism in Aquilaria sp. In order to fulfill the demand for sustainable production of agarwood, chemical, physical and biological methods of inducing artificial infection for agarwood enhancement/production have been formulated. In addition, artificial inoculation of fungi has been used to induce agarwood in Aquilaria trees. In this review, we have discussed the success and limitations of various methods employed for agarwood stimulation and provided the analysis of investigation conducted by various researchers to ascertain the contributory role of fungi (endophytic–pathogenic–epiphytic) on agar formation and chemical composition of oil from artificially infected agarwood. Based on available literature, Xylaria sp., Lasiodiplodia sp., Colletotrichum sp. and Botryosphaeria sp. are promising fungal isolates which deserved to be further studied and scaled up to a commercial level for production of agarwood oil.  相似文献   

7.
Paracoccidioidomycosis ceti is a cutaneous disease of cetaceans caused by uncultivated Paracoccidioides brasiliensis or Paracoccidioides spp. Serological cross-reactions between paracoccidioidomycosis ceti and paracoccidioidomycosis, paracoccidioidomycosis and histoplasmosis, and paracoccidioidomycosis and coccidioidomycosis have been reported before. The present study aimed to detect immunohistochemical cross-reaction between antibodies to Paracoccidioides sp. and Histoplasma capsulatum, and vice versa. Thirty murine sera, obtained from experimental infections of 6 isolates of H. capsulatum, were reacted with paraffin-embedded yeast-form cells of Paracoccidioides sp. derived from a case of paracoccidioidomycosis ceti in Japan. The murine sera were also reacted with human isolates of H. capsulatum yeast cells, with P. brasiliensis yeast cells, and with fungal cells of Coccidioides posadasii. Three dolphins’ sera from cases of paracoccidioidomycosis ceti, two human sera from patients with paracoccidioidomycosis, and a serum from a healthy person with a history of coccidioidomycosis were used in order to determine that the tested fungal cells reacted properly. Sera derived from mice infected with an isolate of H. capsulatum reacted positively against yeast cells of Paracoccidioides sp., yeast cells of P. brasiliensis, and fungal cells of C. posadasii, while those derived from other strains were negative. The present study recorded for the first time the cross-reaction between the yeast cells of H. capsulatum and antibodies against Paracoccidioides spp., the yeast cells of Paracoccidioides sp. and antibodies against H. capsulatum, the yeast cells of Paracoccidioides sp. and antibodies against Coccidioides sp., and fungal cells of C. posadasii and antibodies against Paracoccidioides spp.  相似文献   

8.
Pseudomonas sp., which occupy a variety of ecological niches, have been widely studied for their versatile metabolic capacity to promote plant growth, suppress microbial pathogens, and induce systemic resistance in plants. In this study, a Pseudomonas sp. strain p21, which was isolated from tomato root endophytes, was identified as having antagonism against Aspergillus niger. Further analysis showed that this strain had the ability to biosynthesise siderophores and was less effective in inhibiting the growth of A. niger with the supplementation of Fe3+ in the agar medium. Genomic sequencing and the secondary metabolite cluster analysis demonstrated that Pseudomonas sp. p21 harboured 2 pyoverdine biosynthetic gene clusters, which encode compounds with predicted core structures and two variable tetra-peptide or eleven-peptide chains. The results indicated that siderophore-mediated competition for iron might be an important mechanism in Pseudomonas suppression of the fungal pathogen A. niger and in microbe-pathogen-plant interactions.  相似文献   

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12.
A rust fungus was found on the leaves of Euphorbia helioscopia during a field study in Pakistan. Previously, Melampsora euphorbiae, M. euphorbiae-gerardianae and M. helioscopiae have been reported on E. helioscopia, the first two of which are also known from Pakistan. Morphological observations of the newly collected rust samples detected some differences from the previously described Melampsora species on E. helioscopia. The molecular analysis of the ITS and LSU sequences also detected that the rust is different from the previously reported rusts described from E. helioscopia. Based on both morphological comparisons and sequence analysis, the rust is described here as M. pakistanica sp. nov. This species could have potential as a bio-control agent against its host plant—E. helioscopia—which is a weed of wheat fields in Pakistan and elsewhere in the world.  相似文献   

13.
A new psyllid species, Cacopsylla biwa Inoue, sp. nov., is described from Tokushima Prefecture, Shikoku, Japan. This new species develops only on Eriobotrya japonica (Thunb.) Lindl. (Rosaceae), causing severe damage to its fruits and flowers. It is strongly suspected that C. biwa is an alien species. Morphological similarities and host-plant relationships indicate that C. biwa is most closely related to Cacopsylla eriobotryae (Yang) comb. nov. (transferred from Edentatipsylla Li), which occurs in Taiwan and feeds on Eriobotrya deflexa (Hemsl.) Nakai. Morphological diagnostic characteristics of C. biwa and differences from the other congeners are discussed. Information is provided on the biology and life cycle of the new species.  相似文献   

14.
A new strain of Chlorella sp. (Chlorella-Arc), isolated from Arctic glacier melt water, was found to have high specific growth rates (μ) between 3 and 27 °C, with a maximum specific growth rate of 0.85 day?1 at 15 °C, indicating that this strain was a eurythermal strain with a broad temperature tolerance range. To understand its acclimation strategies to low and high temperatures, the physiological and biochemical responses of the Chlorella-Arc to temperature were studied and compared with those of a temperate Chlorella pyrenoidosa strain (Chlorella-Temp). As indicated by declining F v/F m, photoinhibition occurred in Chlorella-Arc at low temperature. However, Chlorella-Arc reduced the size of the light-harvesting complex (LHC) to alleviate photoinhibition, as indicated by an increasing Chl a/b ratio with decreasing temperatures. Interestingly, Chlorella-Arc tended to secrete soluble sugar into the culture medium with increasing temperature, while its intracellular soluble sugar content did not vary with temperature changes, indicating that the algal cells might suffer from osmotic stress at high temperature, which could be adjusted by excretion of soluble sugar. Chlorella-Arc accumulated protein and lipids under lower temperatures (<15 °C), and its metabolism switched to synthesis of soluble sugar as temperatures rose. This reflects a flexible ability of Chlorella-Arc to regulate carbon and energy distribution when exposed to wide temperature shifts. More saturated fatty acids (SFA) in Chlorella-Arc than Chlorella-Temp also might serve as the energy source for growth in the cold and contribute to its cold tolerance.  相似文献   

15.
This study evaluated rickettsial infection in ticks collected on toads from the northern Brazilian Amazon (Amapá state), where to our knowledge there are neither records of ticks from amphibians nor rickettsial infections in ticks. During 2016–2017, a total of 22 free-living toads were captured and identified as Rhinella marina. Overall, 12 (54.5%) toads were parasitized by a total of 97 ticks (6 males, 39 females, 31 nymphs, 21 larvae), giving a mean intensity of 8.1 ticks per infested toad. Two tick species were morphologically identified: Amblyomma rotundatum Koch (31 females, 14 nymphs), and Amblyomma dissimile Koch (6 males, 8 females, 17 nymphs). The 21 larvae were morphologically denoted as Amblyomma sp. Five toads were co-infested by A. rotundatum and A. dissimile. Morphological identifications were confirmed by nucleotide sequencing of fragments of the mitochondrial genes 16S rDNA, 12S rDNA and/or COX1. A total of 54 ticks were analyzed for the presence of rickettsial DNA. Eleven (9 females and 2 nymphs) out of 14 A. rotundatum ticks contained Rickettsia bellii. None of the 25 specimens of A. dissimile (6 males, 6 females, 13 nymphs) contained amplifiable rickettsial DNA. From 15 Amblyomma sp. larvae, a pool of 10 individuals contained Rickettsia sp. strain Colombianensi. Sequencing of the 16S rDNA amplicon derived from the positive pool yielded a sequence of A. dissimile. We detected Rickettsia sp. strain Colombianensi for the first time in Brazil. Prior records of this agent were restricted to Colombia and Honduras. In addition, we report the presence of A. rotundatum for the first time in the state of Amapá, where the only other record of A. dissimile was registered over 20 years ago.  相似文献   

16.
Helicobacter (H.) pylori infection is an important risk factor for gastric cancer that causes gastric inflammation. Inflammatory chemokines such as interleukin (IL)-8 and regulated on activation normal T cell expressed and secreted (RANTES) are elevated in the gastric mucosa by H. pylori. This study aimed to investigate the effects of Lactobacillus paracasei strain 06TCa19, a probiotic strain, on IL-8 and RANTES expression and production induced by H. pylori using human gastric epithelial cell lines. Strain 06TCa19 was shown to suppress H. pylori-mediated elevation of gene expression related to these chemokines in MKN45 cells. The strain also suppressed the increase in IL-8 and RANTES products induced by H. pylori in AGS cells as well as in MKN45 cells. In MKN45 cells inoculated with H. pylori, strain 06TCa19 was shown to downregulate the activation of NF-κB and p38 MAPK signaling pathways. Additionally, the level of the CagA virulence protein of H. pylori in the MKN45 cells and the number of viable H. pylori adhering to MKN45 cells decreased with the addition of strain 06TCa19. Moreover, the strain 06TCa19 notably increased lactic acid in the supernatant of MKN45 cells. Thus, lactic acid released from strain 06TCa19 might have inhibited the adhesion of H. pylori to MKN45 cells and prevented the insertion of H. pylori CagA into the cells, and elevation of IL-8 and RANTES genes and proteins might be suppressed by downregulating the NF-κB and p38 MAPK pathways. Therefore, use of strain 06TCa19 may prevent H. pylori-associated gastric inflammation.  相似文献   

17.
Examination of three species of batfishes (Teleostei: Epphippidae) from off Lizard and Heron Islands on the Great Barrier Reef led to the discovery of specimens of the trematode genus Paradiscogaster Yamaguti, 1934 (Digenea: Faustulidae). Morphological analysis demonstrated that the new specimens represented four morphotypes which we interpret to be new species: Paradiscogaster martini n. sp., P. vichovae n. sp. and P. brayi n. sp. from Platax orbicularis (Forsskål) and P. pinnatus (Linnaeus) off Lizard Island, and P. nitschkei n. sp. from P. teira (Forsskål) off Heron Island. Published material was re-examined and the specimens identified as P. chaetodontis okinawensis Yamaguti, 1971 from P. pinnatus from Okinawa, Japan, actually represent the new species P. brayi n. sp., demonstrating that some species of Paradiscogaster have wide geographical distributions. ITS2 rDNA data for the four morphotypes differ by 4–39 base pairs confirming the delineation of the four species proposed. A feature of this study is the recognition of Platax spp. as an important host group for Paradiscogaster, with the new species placing them as the second richest host group for these parasites after the Chaetodontidae.  相似文献   

18.
The genus Praepedaliodes Forster, 1964, the only representative of the mega-diverse mostly Andean Pedaliodes complex lineage in the Brazilian Atlantic Forest, is revised. Prior to this study, four species were known, P. phanias (Hewitson, 1862), P. granulata (Butler, 1868), P. amussis (Thieme, 1905) and P. exul (Thieme, 1905). Here, a further six are described, all from SE Brazil, expanding to 10 the number of species in this genus. Lectotypes are designated for P. phanias, P. granulata and P. amussis. The genus is most diverse in the Serra da Mantiqueira (São Paulo, Rio de Janeiro, Minas Gerais) and in the Serra Geral (Paraná, Santa Catarina) with seven species occurring in both ranges. Praepedaliodes phanias is the most widespread species and the only one found in the western part of the Atlantic Forest; only this species and P. duartei Dias, Dolibaina & Pyrcz n. sp. occurring to near sea level. Other species, P. zaccae Dolibaina, Dias & Pyrcz n. sp., P. francinii Freitas & Pyrcz n. sp., P. sequeirae Pyrcz, Dias & Dolbaina n. sp., P. landryi Pyrcz & Freitas n. sp. and P. pawlaki Pyrcz & Boyer n. sp. are strictly montane and the highest species richness is reached at 1400–1800 m. One species, P. sequeirae n. sp., is a narrow endemic found only at timberline in the Agulhas Negras massif above 2300 m. Immature stages are described for two species, P. phanias and P. landryi n. sp. Molecular data (barcode region of cytochrome oxidase, subunit I) and adult morphology, including male and female genitalia, support the genus as monophyletic, belonging to a predominantly Andean clade of the Pedaliodes Butler, 1867 complex. Morphological evidences, in particular female genitalia comparative analysis, indicate the genera Physcopedaliodes Forster, 1964 and Panyapedaliodes Forster, 1964 as possibly the closest relatives to Praepedaliodes. Molecular data are inconclusive in this respect.  相似文献   

19.
A Bacillus sp. strain named BRC1 is capable of producing 2,3-butanediol (2,3-BD) using hydrolysates of the Jerusalem artichoke tuber (JAT), a rich source of the fructose polymer inulin. To enhance 2,3-BD production, we undertook an extensive analysis of the Bacillus sp. BRC1 genome, identifying a putative gene (sacC) encoding a fructan hydrolysis enzyme and characterizing the activity of the resulting recombinant protein expressed in and purified from Escherichia coli. Introduction of the sacC gene into Bacillus sp. BRC1 using an expression vector increased enzymatic activity more than twofold. Consistent with this increased enzyme expression, 2,3-BD production from JAT was also increased from 3.98 to 8.10 g L?1. Fed-batch fermentation of the recombinant strain produced a maximal level of 2,3-BD production of 28.6 g L?1, showing a high theoretical yield of 92.3%.  相似文献   

20.
Infections by non-albicans Candida species are a life-threatening condition, and formation of biofilms can lead to treatment failure in a clinical setting. This study was aimed to demonstrate the in vitro antibiofilm activity of fluconazole (FLU) and voriconazole (VOR) against C. glabrata, C. parapsilosis and C. rugosa with diverse antifungal susceptibilities to FLU and VOR. The antibiofilm activities of FLU and VOR in the form of suspension as well as pre-coatings were assessed by XTT [2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide] reduction assay. Morphological and intracellular changes exerted by the antifungal drugs on Candida cells were examined by scanning electron microscope (SEM) and transmission electron microscope (TEM). The results of the antibiofilm activities showed that FLU drug suspension was capable of killing C. parapsilosis and C. rugosa at minimum inhibitory concentrations (MICs) of 4× MIC FLU and 256× MIC FLU, respectively. While VOR MICs ranging from 2× to 32× were capable of killing the biofilms of all Candida spp tested. The antibiofilm activities of pre-coated FLU were able to kill the biofilms at ¼× MIC FLU and ½× MIC FLU for C. parapsilosis and C. rugosa strains, respectively. While pre-coated VOR was able to kill the biofilms, all three Candida sp at ½× MIC VOR. SEM and TEM examinations showed that FLU and VOR treatments exerted significant impact on Candida cell with various degrees of morphological changes. In conclusion, a fourfold reduction in MIC50 of FLU and VOR towards ATCC strains of C. glabrata, C. rugosa and C. rugosa clinical strain was observed in this study.  相似文献   

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