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A search for the organisms responsible for anaerobic betaine degradation in soda lakes resulted in isolation of a novel bacterial strain, designated Z-7014T. The cells were Gram-stain-negative, non-endospore-forming rods. Growth occurred at 8–52 °C (optimum 40–45 °C), pH 7.1–10.1 (optimum pH 8.1–8.8) and 1.0–3.5 M Na+ (optimum 1.8 M), i.e. it can be regarded as a haloalkaliphile. The strain utilized a limited range of substrates, mostly peptonaceous but not amino acids, and was able to degrade betaine. Growth on betaine occurred only in the presence of peptonaceous substances which could not be replaced by vitamins. The G + C content of the genomic DNA of strain Z-7014T was 36.1 mol%. The major cellular fatty acids (>5% of the total) were C16:0 DMA, C18: 0 DMA, C16:1ω8, C16:0, C18:1 DMA, C16:1 DMA, C18:1ω9, and C18:0. Phylogenetic analysis of the 16S rRNA gene sequence revealed that strain Z-7014T formed a distinct evolutionary lineage in the order Halanaerobiales with the highest similarity to Halarsenitibacter silvermanii SLAS-1T (83.6%), Halothermothrix orenii H168T (85.6%), and Halocella cellulosilytica DSM 7362T (85.6%). AAI and POCP values between strain Z-7014T and type strains of the order Halanaerobiales were 51.7–57.8%, and 33.8–58.3%, respectively. Based on polyphasic results including phylogenomic data, the novel strain could be distinguished from other genera, which suggests that strain Z-7014T represents a novel species of a new genus, for which the name Halonatronomonas betaini gen. nov., sp. nov. is proposed. The type strain is Z-7014T (=KCTC 25237T = VKM B-3506T). On the basis of phylogenomic data, it is also proposed to evolve two novel families Halarsenitibacteraceae fam. nov. and Halothermotrichaceae fam. nov. within the current order Halanaerobiales.  相似文献   

3.
Nine bacterial strains designated MT3-5-12T, MT3-5-27, MTV1-9, S-DT1-15T, S-DT1-34, MTV5-3T, MTV4-17, MTV5-12 and MTV5-13 were isolated from the upper layer (1–5 cm in depth) of tidal flat sediment in Quanzhou Bay, China. The 16S rRNA gene of these strains shared maximum sequence similarities with Aestuariivivens insulae KCTC 42350T of 94.9–97.1%. Phylogenetic analyses based on 16S rRNA gene sequences and 120 conserved concatenated proteins placed these strains in three novel phylogenetic clades affiliated to the genus Aestuariivivens of the family Flavobacteriaceae. Strains MT3-5-12T, MT3-5-27 and MTV1-9 were phylogenetically close to A. insulae KCTC 42350T. The average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between strains MT3-5-12Tand MTV1-9 and A. insulae KCTC 42350T were estimated to be 78.5-78.7% and 22.5%, respectively. Strains S-DT1-15T and S-DT1-34 formed a distinctly separated clade from A. insulae KCTC 42350T. The ANI and dDDH values between strains S-DT1-15T and S-DT1-34 and A. insulae KCTC 42350T were 76.3–76.4% and 20.4–20.5%, respectively. The other four strains MTV5-3T, MTV4-17, MTV5-12 and MTV5-13, formed a third novel clade, distinctly separated from A. insulae KCTC 42350T. The ANI and dDDH values between strains MTV5-3T and MTV4-17 and A. insulae KCTC 42350T were 74.7% and 19.1–19.2%, respectively. The phylogenetic analyses and whole genomic comparisons, combined with phenotypic and chemotaxonomic features, strongly supported the nine strains could be classified as three novel species within the genus Aestuariivivens, for which the names Aestuariivivens marinum sp. nov. MT3-5-12T, Aestuariivivens sediminis sp. nov. S-DT1-15T, and Aestuariivivens sediminicola sp. nov. MTV5-3T are proposed.  相似文献   

4.
A spiral-shaped, highly motile bacterium was isolated from freshwater sulfidic sediment. Strain J10T is a facultative autotroph utilizing sulfide, thiosulfate, and sulfur as the electron donors in microoxic conditions. Despite high 16S rRNA gene sequence sequence identity to Magnetospirillum gryphiswaldense MSR-1 T (99.6 %), digital DNA-DNA hybridisation homology and average nucleotide identity between the two strains was of the different species level (25 % and 83 %, respectively). Strain J10T is not magnetotactic. The DNA G + C content of strain J10T is 61.9 %. The predominant phospholipid ester-linked fatty acids are C18:1ω7, C16:1ω7, and C16:0. Strain J10T (=DSM 23205 T = VKM B-3486 T) is the first strain of the genus Magnetospirillum showing lithoautotrophic growth and is proposed here as a novel species, Magnetospirillum sulfuroxidans sp. nov. In addition, we propose to establish a framework for distinguishing genera and families within the order Rhodospirillales based on phylogenomic analysis using the threshold values for average amino acid identity at ̴ 72 % for genera and ̴ 60 % for families. According to this, we propose to divide the existing genus Magnetospirillum into three genera: Magnetospirillum, Paramagnetospirillum, and Phaeospirillum, constituting a separate family Magnetospirillaceae fam. nov. in the order Rhodospirillales. Furthermore, phylogenomic data suggest that this order should accomodate six more new family level groups including Magnetospiraceae fam. nov., Magnetovibrionaceae fam. nov., Dongiaceae fam. nov., Niveispirillaceae fam. nov., Fodinicurvataceae fam. nov., and Oceanibaculaceae fam. nov.  相似文献   

5.
Bacteria within the phylum Planctomycetota are biologically relevant due to unique characteristics among prokaryotes. Members of the genus Rhodopirellula can be abundant in marine habitats, however, only six species are currently validly described. In this study, we expand the explored genus diversity by formally describing a novel species. The pink-coloured strain ICT_H3.1T was isolated from brackish sediments collected in the Tagus estuary (Portugal) and a 16S rRNA gene sequence-based analysis placed this strain into the genus Rhodopirellula (family Pirellulaceae). The closest type strain is Rhodopirellula rubra LF2T, suggested by a similarity of 98.4% of the 16S rRNA gene sequence. Strain ICT_H3.1T is heterotrophic, aerobic and able to grow under microaerobic conditions. The strain grows between 15 and 37 °C, over a range of pH 6.5 to 11.0 and from 1 to 8% (w/v) NaCl. Several nitrogen and carbon sources were utilized by the novel isolate. Cells have an elongated pear-shape with 2.0 ± 0.3 × 0.9 ± 0.2 µm in size. Cells of strain ICT_H3.1T cluster in rosettes through a holdfast structure and divide by budding. Younger cells are motile. Ultrathin cell sections show cytoplasmic membrane invaginations and polar fimbriae. The genome size is 9,072,081 base pairs with a DNA G + C content of 56.1 mol%. Genomic, physiological and morphological comparison of strain ICT_H3.1T with its relatives suggest that it belongs to a novel species within the genus Rhodopirellula. Hence, we propose the name Rhodopirellula aestuarii sp. nov., represented by ICT_H3.1T (=CECT30431T = LMG32464T) as the type strain of this novel species.16S rRNA gene accession number: GenBank = OK001858.Genome accession number: The Whole Genome Shotgun project has been deposited at DDBJ/ENA/GenBank under the accession JAMQBK000000000. The version described in this paper is version JAMQBK010000000.  相似文献   

6.
Strain LMG 31809 T was isolated from a top soil sample of a temperate, mixed deciduous forest in Belgium. Comparison of its 16S rRNA gene sequence with that of type strains of bacteria with validly published names positioned it in the class Alphaproteobacteria and highlighted a major evolutionary divergence from its near neighbor species which represented species of the orders Emcibacterales and Sphingomonadales. 16S rRNA amplicon sequencing of the same soil sample revealed a highly diverse community in which Acidobacteria and Alphaproteobacteria predominated, but failed to yield amplicon sequence variants highly similar to that of strain LMG 31809 T. There were no metagenome assembled genomes that corresponded to the same species and a comprehensive analysis of public 16S rRNA amplicon sequencing data sets demonstrated that strain LMG 31809 T represents a rare biosphere bacterium that occurs at very low abundances in multiple soil and water-related ecosystems. The genome analysis suggested that this strain is a strictly aerobic heterotroph that is asaccharolytic and uses organic acids and possibly aromatic compounds as growth substrates. We propose to classify LMG 31809 T as a novel species within a novel genus, Govania unica gen. nov., sp. nov, within the novel family Govaniaceae of the class Alphaproteobacteria. Its type strain is LMG 31809 T (=CECT 30155 T). The whole-genome sequence of strain LMG 31809 T has a size of 3.21 Mbp. The G + C content is 58.99 mol%. The 16S rRNA gene and whole-genome sequences of strain LMG 31809 T are publicly available under accession numbers OQ161091 and JANWOI000000000, respectively.  相似文献   

7.
The strains designed PP-18T, JC-4 and JC-7 isolated from soils, were Gram-stain-positive rods, facultative anaerobe, endospore-forming bacteria. The strains produced l-lactic acid from glucose. They showed positive for catalase but negative for oxidase, nitrate reduction and arginine hydrolysis. Strains P-18T, JC-4 and JC-7 were closely related to Weizmannia coagulans LMG 6326T (97.27–97.64%) and W. acidiproducens KCTC 13078T (96.46–96.74%) based on 16S rRNA gene sequence similarity, respectively. They contained meso-diaminopimelic acid in cell wall peptidoglycan and had seven isoprene units (MK-7) as the predominant menaquinone. The major cellular fatty acids of strain PP-18T were iso-C15:0, anteiso-C17:0, iso-C16:0 and anteiso-C15:0. The ANIb and ANIm values among the genomes of strains PP-18T, JC-4 and JC-7 are above 99.4% while their ANIb and ANIm values among them and W. coagulans LMG 6326T and W. acidiproducens KCTC 13078T were ranged from 76.61 to 79.59%. These 3 strains showed the digital DNA-DNA hybridization (dDDH) values of 20.7–23.6% when compared with W. coagulans LMG 6326T and W. acidiproducens DSM 23148T. The DNA G + C contents of strains PP-18T, JC-4 and JC-7 were 45.82%, 45.86% and 45.86%, respectively. The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol and phosphoglycolipids. The results of phenotypic and chemotaxonomic characteristics and whole-genome analysis indicated that the strains PP-18T, JC-4 and JC-7 should be represented as a novel species within the genus Weizmannia for which the name Weizmannia acidilactici sp. nov. is proposed. The type strain is PP-18T (=KCTC 33974T = NBRC 113028T = TISTR 2515T).  相似文献   

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Marine sponges represent a rich source of uncharacterized microbial diversity, and many are host to microorganisms that produce biologically active specialized metabolites. Here, a polyphasic approach was used to characterize two Actinobacteria strains, P01-B04T and P01-F02, that were isolated from the marine sponges Geodia barretti (Bowerbank, 1858) and Antho dichotoma (Esper, 1794), respectively. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strains P01-B04T and P01-F02 are closely related to Streptomyces beijiangensis DSM 41794T, Streptomyces laculatispora NRRL B-24909T, and Streptomyces brevispora NRRL B-24910T. The two strains showed nearly identical 16S rRNA gene sequences (99.93%), and the average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) relatedness values were 99.96% and 99.6%, respectively, suggesting that these strains are affiliated with the same species. Chemotaxonomic and culture characteristics of both strains were also consistent with the genus Streptomyces, while phenotypic properties, genome-based comparisons, and phylogenomic analyses distinguished strains P01-B04T and P01-F02 from their closest phylogenetic relatives. In silico analysis predicted that the 8.9 Mb genome of P01-B04T contains at least 41 biosynthetic gene clusters (BGCs) encoding secondary metabolites, indicating that this strain could express diverse bioactive metabolites; in support of this prediction, this strain expressed antibacterial activity against Gram-positive bacteria including a clinical isolate of methicillin-resistant Staphylococcus aureus (MRSA) EAMC30. Based on these results, the marine sponge-associated isolates represent a novel species of the genus Streptomyces, for which the name Streptomyces poriferorum sp. nov. is proposed, with P01-B04T (=DSM 111306T = CCM 9048T) as the type strain.  相似文献   

10.
This current study presents, for the first time, the complete chloroplast genome of two Cleomaceae species: Dipterygium glaucum and Cleome chrysantha in order to evaluate the evolutionary relationship. The cp genome is 158,576 bp in length with 35.74% GC content in D. glaucum and 158,111 bp with 35.96% GC in C. chrysantha. Inverted repeats IR 26,209 bp, 26,251 bp each, LSC of 87,738 bp, 87,184 bp and SSC of 18,420 bp, 18,425 bp respectively. There are 136 genes in the genome, which includes 80 protein coding genes, 31 tRNA genes and four rRNA genes were observed in both chloroplast genomes. 117 genes are unique while the remaining 19 genes are duplicated in IR regions. The analysis of repeats shows that the cp genome includes all types of repeats with more frequent occurrences of palindromic; Also, this analysis indicates that the total number of simple sequence repeats (SSR) were 323 in D. glaucum, and 313 in C. chrysantha, of which the majority of the SSRs in these plastid genomes were mononucleotide repeats A/T which are located in the intergenic spacer. Moreover, the comparative analysis of the four cp sequences revealed four hotspot genes (atpF, rpoC2, rps19, and ycf1), these variable regions could be used as molecular makers for the species authentication as well as resources for inferring phylogenetic relationships of the species. All the relationships in the phylogenetic tree are with high support, this indicate that the complete chloroplast genome is a useful data for inferring phylogenetic relationship within the Cleomaceae and other families. The simple sequence repeats identified will be useful for identification, genetic diversity, and other evolutionary studies of the species. This study reported the first cp genome of the genus Dipterygium and Cleome. The finding of this study will be beneficial for biological disciplines such as evolutionary and genetic diversity studies of the species within the core Cleomaceae.  相似文献   

11.
Trichuridae family has a genetic and morphological variability between species affecting rodents, but it is considerably hard to morphologically diagnose species within the genus of Trichuris and the individuals of these species are identified according to their host, as it is known that Trichuris spp. is strictly host-specific. However, some species lack host specificity. So, it is necessary to use molecular data in order to well identify the Trichuris spp. in Egyptian rodents. The host examined in the current research is Psammomys obesus and the molecularly identified species from its cecum is Trichuris arvicolae. In addition, Trichuris arvicolae was subjected to in vitro treatment with Androctonus crassicauda Crude Venom as a model of natural alternative treatment for gastrointestinal nematodes that increasingly develop anthelmintic drug resistance. The changes in Trichuris arvicolae were monitored using scanning electron microscopy, Androctonus crassicauda Crude Venom made a significant ultrastructural surface changes in Trichuris arvicolae, including marked cuticular sloughing, disintegrated bacillary glands, bursting of vulva and edema of anal region. This study was done for closer identification of Trichuris spp. infecting rodents in Egypt and evaluating the efficacy of Androctonus crassicauda Crude Venom in vitro.  相似文献   

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Two Gram-stain-negative, strictly aerobic, moderately halophilic, non-spore-forming and rod-shaped bacteria, designated M5N1S17T and M5N1S15, were isolated from saline soil in Baotou, China. A phylogenetic analysis based on 16S rRNA gene sequences showed that the two strains clustered closely with Halomonas montanilacus PYC7WT and shared 99.1 and 99.3% sequence similarities, respectively. The average nucleotide identity based on BLAST (ANIb) and MUMmer (ANIm) values of the two strains with each other were 95.5% and 96.7%, respectively, while the ANIb and ANIm values between the two strains and 15 closer Halomonas species were 74.8–91.3% and 84.1–92.6%, respectively. The major polar lipids of M5N1S17T are diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylinositol, and an unidentified phospholipid. The major polar lipids of M5N1S15 are diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylinositol, two unidentified phospholipids, and an unidentified lipid. The predominant ubiquinone in the two strains is Q-9. The major fatty acids of the two strains are C18:1 ω6c and/or C18:1 ω7c, C16:0, and C16:1 ω7c and/or C16:1 ω6c. Based on phylogenetic, phenotypic, and physiological results, strains M5N1S17T and M5N1S15 should be identified as a novel species of the genus Halomonas, for which Halomonas alkalisoli sp. nov. is proposed. The type strain is M5N1S17T (= CGMCC 1.19023T = KCTC 92130T). The phylogenetic trees showed that Halomonas daqingensis CGMCC 1.6443T clustered tightly with Halomonas desiderata FB2T, and the two strains shared >98.0% of ANI values with each other. Therefore, we propose the reclassification of H. daqingensis Wu et al. 2008 as a later heterotypic synonym of H. desiderata Berendes et al. 1996.  相似文献   

14.
Sunflower occupies the fourth position among oilseed crops the around the world. Eceriferum (CER) is an important gene family that plays critical role in very-long-chain fatty acids elongation and biosynthesis of epicuticular waxes under both biotic and abiotic stress conditions. The aim of present study was to investigate the effect of sunflower CER genes during drought stress condition. Thus, comparative analysis was undertaken for sunflower CER genes with Arabidopsis genome to determine phylogenetic relationship, chromosomal mapping, gene structures, gene ontology and conserved motifs. Furthermore, we subjected the sunflower cultivars under drought stress and used qRT-PCR analysis to explore the expression pattern of CER genes during drought conditions. We identified thirty-seven unevenly distributed CER genes in the sunflower genome. The phylogenetic analysis revealed that CER genes were grouped into seven clades in Arabidopsis, Helianthus annuus, and Gossypium hirsutum. Expression analysis showed that genes CER10 and CER60 were upregulated in sunflower during drought conditions, indicating that these genes are activated during drought stress. The results obtained will serve to characterize the CER gene family in sunflower and exploit the role of these genes in wax biosynthesis under limited water conditions.Key messageCuticular waxes protect the plants from drought stress, so we observed the expression of wax bio synthesis genes in recently sequences genome of Helianthus annuus. We observed that expression of wax biosynthesis genes CER10 and CER60 was upregulated when the plants were subjected to drought stress.  相似文献   

15.
A polyphasic taxonomic approach was used to characterize the four strains P2653T, P2652, P2498, and P2647, isolated from Antarctic regolith samples. Initial genotype screening performed by PCR fingerprinting based on repetitive sequences showed that the isolates studied formed a coherent cluster separated from the other Pseudomonas species. Identification results based on 16S rRNA gene sequences showed the highest sequence similarity with Pseudomonas graminis (99.7%), which was confirmed by multilocus sequence analysis using the rpoB, rpoD, and gyrB genes. Genome sequence comparison of P2653T with the most related P. graminis type strain DSM 11363T revealed an average nucleotide identity of 92.1% and a digital DNA-DNA hybridization value of 46.6%. The major fatty acids for all Antarctic strains were C16:0, Summed Feature 3 (C16:1 ω7c/C16:1 ω6c) and Summed Feature 8 (C18:1 ω7c/C18:1 ω6c). The predominant respiratory quinone was Q-9, and the major polar lipids were phosphatidylethanolamine, diphosphatidylglycerol, and phosphatidylglycerol. The regolith strains could be differentiated from related species by the absence of arginine dihydrolase, ornithine and lysine decarboxylase and by negative tyrosine hydrolysis. The results of this polyphasic study allowed the genotypic and phenotypic differentiation of four analysed strains from the closest related species, which confirmed that the strains represent a novel species within the genus Pseudomonas, for which the name Pseudomonas petrae sp. nov. is proposed with P2653T (CCM 8850T = DSM 112068T = LMG 30619T) as the type strain.  相似文献   

16.
Lactobacilli are dominant in zha-chili. This study provides a taxonomic characterization of five bacterial strains isolated from zha-chili in China. The cells were Gram-positive, facultative anaerobic, non-spore-forming, flagella-free, catalase-negative, heterofermentative, pentose-fermenting, and gamma-aminobutyric acid (GABA)-producing rods. For HBUAS51241T, HBUAS51329, and HBUAS51416, C16:0, C18:1 ω9c and C19:0 iso were the predominant cellular fatty acids; diphosphatidylglycerol (DPG), phosphatidylglycerol (DP), glycolipids (GL), and glycolipids (AL) were the major phospholipids. While for HBUAS51383T and HBUAS58055, C16:0, C18:1 ω9c, C19:0 cyclo ω8c were the predominant cellular fatty acids; DPG, DP, GL, and AL were the major phospholipids. Strains HBUAS51241T, HBUAS51329, and HBUAS51416 showed 98.1–99.1% 16S rRNA gene sequence similarity, 80.2–81.4% ANI, 87.7–90.0% AAI, and 23.8–32.8% digital DDH to their closest related type strains Levilactobacillus hammesii DSM 16381T, Levilactobacillus parabrevis ATCC 53295T, and Levilactobacillus fuyuanensis 244-4T. Strains HBUAS51383T and HBUAS58055 showed 98.7–99.5% 16S rRNA gene sequence similarity, 75.4–81.4% ANI, 75.5–89.1% AAI, and 19.7–24.0% digital DDH to their closest related type strains Secundilactobacillus silagincola IWT5T, Secundilactobacillus silagei JCM 19001T, Secundilactobacillus pentosiphilus IWT25T, Secundilactobacillus mixtipabuli IWT30T, Secundilactobacillus odoratitofui DSM 19909T, and Secundilactobacillus similis DSM 23365T. The central carbon metabolism pathways for the five strains were summarizeded. Based on the phenotypic, chemotaxonomic, and genomic data, we propose two novel species Levilactobacillus tujiorum sp. nov. whose type strain is HBUAS51241T (=GDMCC 1.3022T = JCM 35241T), and Secundilactobacillus angelensis sp. nov. whose type strain is HBUAS51383T (=GDMCC 1.3021T = JCM 35209T).  相似文献   

17.
《Journal of Asia》2023,26(1):102023
Endosymbionts have gained prominence as a potential tool for biological control strategies in reducing vector-borne diseases. This study aimed to evaluate the presence of Arsenophonus, Spiroplasma, and Rickettsia endosymbionts in wild specimens of phlebotomine sand flies, as well as in culicids collected in different regions of Colombia. Analyses were conducted through conventional PCR, Sanger sequencing of the 16S rRNA gene, and phylogenetic analyses. Individuals from among 946 phlebotomine sand flies and 143 mosquitoes were selected for taxonomic identification confirmed through the analysis of the cytochrome oxidase subunit I gene sequences. Results showed the presence of Arsenophonus bacteria in samples of Lutzomyia longipalpis, Psychodopygus panamensis, and Pintomyia evansi. Arsenophonus sequences associated with Lu. longipalpis and Ps. panamensis are phylogenetically located near to sequences of louse flies, with K2P genetic distances of 0.006. In contrast, sequences obtained from Pi. evansi are phylogenetically located near Arsenophonus nasoniae (K2P 0.001–0.014). Other sequences of endosymbionts similar to Arsenophonus with high K2P genetic distances (0.056–0.097), when compared to different reference strains of this endosymbiont, were also found in other samples of Lu. longipalpis and Ae. aegypti. To the best of our knowledge, this is the first successful attempt to detect and elucidate the phylogenetic relationship of Arsenophonus in phlebotomine sand flies, yet its role within these insect vectors remains to be fully determined; therefore, the importance of entomological surveys that help better understand its behavior and potential use as a control agent is required to enable the proactive reduction of sand fly populations.  相似文献   

18.
In two previous studies, we identified compound 1 as a moderate GroEL/ES inhibitor with weak to moderate antibacterial activity against Gram-positive and Gram-negative bacteria including Bacillus subtilis, methicillin-resistant Staphylococcus aureus, Klebsiella pneumonia, Acinetobacter baumannii, and SM101 Escherichia coli (which has a compromised lipopolysaccharide biosynthetic pathway making bacteria more permeable to drugs). Extending from those studies, we developed two series of analogs with key substructures resembling those of known antibacterials, nitroxoline (hydroxyquinoline moiety) and nifuroxazide/nitrofurantoin (bis-cyclic-N-acylhydrazone scaffolds). Through biochemical and cell-based assays, we identified potent GroEL/ES inhibitors that selectively blocked E. faecium, S. aureus, and E. coli proliferation with low cytotoxicity to human colon and intestine cells in vitro. Initially, only the hydroxyquinoline-bearing analogs were found to be potent inhibitors in our GroEL/ES-mediated substrate refolding assays; however, subsequent testing in the presence of an E. coli nitroreductase (NfsB) in situ indicated that metabolites of the nitrofuran-bearing analogs were potent GroEL/ES inhibitor pro-drugs. Consequently, this study has identified a new target of nitrofuran-containing drugs, and is the first reported instance of such a unique class of GroEL/ES chaperonin inhibitors. The intriguing results presented herein provide impetus for expanded studies to validate inhibitor mechanisms and optimize this antibacterial class using the respective GroEL/ES chaperonin systems and nitroreductases from E. coli and the ESKAPE bacteria.  相似文献   

19.
Mexico hosts the highest species richness of pines (Pinus, Pinaceae) worldwide; however, the priority areas for their conservation in the country are unknown. In this study, the ecological niche of the 50 native pine species was modeled. Then, through a multi-criteria analysis, the priority areas for the conservation of the genus Pinus were identified according to the spatial patterns of richness, geographic rareness, irreplaceability, the level of vulnerability of their habitat and the status of legal protection. The results revealed that the regions with high species richness differed from those with high endemism. Also, most pine species have undergone processes of habitat degradation, having been the endemic species the most affected. The priority areas covered regions with high species richness, high endemism, and highly degraded forests, located at mountainous portions of the Baja California Peninsula, the Sierra Madre Occidental, the Sierra Madre Oriental, the Trans-Mexican Volcanic Belt, and the Sierra Madre del Sur. A low proportion of priority areas overlapped with protected areas or terrestrial regions considered priorities for biological conservation. These results suggest that conservation efforts for this genus should be focused beyond regions with high species richness and current protected areas. Besides, the priority areas identified in this study can be the basis to create biological corridors and new protected areas, which could contribute significantly to the conservation of this genus in Mexico.  相似文献   

20.
Trypanosoma cruzi is the agent of Chagas disease, an infection that affects around 8 million people worldwide. The search for new anti-T. cruzi drugs are relevant, mainly because the treatment of this disease is limited to two drugs. The objective of this study was to investigate the trypanocidal and cytotoxic activity and elucidate the chemical profile of extracts from the roots of the Lonchocarpus cultratus. Roots from L. cultratus were submitted to successive extractions with hexane, dichloromethane, and methanol, resulting in LCH, LCD, and LCM extracts, respectively. Characterization of extracts was done using 1H-RMN, 13C-RMN, CC and TLC. Treatment of T. cruzi forms (epimastigotes, trypomastigotes, and amastigotes) with crescent concentrations of LCH, LCD, and LCM was done for 72, 48, and 48 h, respectively. After this, the percentage of inhibition and IC50/LC50 were calculated. Benznidazole was used as a positive control. Murine macrophages were treated with different concentrations of both extracts for 48 h, and after, the cellular viability was determined by the MTT method and CC50 was calculated. The chalcones derricin and lonchocarpine were identified in the hexane extract, and for the first time in the genus Lonchocarpus, the presence of a dihydrolonchocarpine derivative was observed. Other chalcones such as isocordoin and erioschalcone B were detected in the dichloromethane extract. The dichloromethane extract showed higher activity against all tested forms of T. cruzi than the other two extracts, with IC50 values of 10.98, 2.42, and 0.83 µg/mL, respectively; these values are very close to those of benznidazole. Although the dichloromethane extract presented a cytotoxic effect against mammalian cells, it showed selectivity against amastigotes. The methanolic extract showed the lowest anti-T. cruzi activity but was non-toxic to peritoneal murine macrophages. Thus, the genus Lonchocarpus had demonstrated in the past action against epimastigotes forms of T. cruzi but is the first time that the activity against infective forms is showed, which leading to further studies with in vivo tests.  相似文献   

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