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1.
Molecules ; 25(23)2020 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-33260521

RESUMO

Cryptocarya alba (Peumo; CA) and Laurelia sempervirens (Laurel; LS) are herbs native to the Chilean highlands and have historically been used for medicinal purposes by the Huilliches people. In this work, the essential oils were extracted using hydrodistillation in Clevenger apparatus and analyzed by GC-MS to determine their composition. The antioxidant capacity (AC) was evaluated in vitro. The cytotoxicity was determined using cell line cultures both non tumoral and tumoral. The toxicity was determined using the nematode Caenorhabditis elegans. The antimicrobial activity was evaluated against 52 bacteria using the agar disc diffusion method and the minimum inhibitory concentrations (MICs) were determined. The principal compounds found in C. alba essential oil (CA_EO) were α-terpineol (24.96%) and eucalyptol (21.63%) and were isazafrol (91.9%) in L. sempervirens essential oil (LS_EO). Both EOs showed antioxidant capacity in vitro. Both EO showed antibacterial activity against bacteria using. LS_EO showed more inhibitory effect on these cell lines respect to CA_EO. Both EOs showed toxicity against the nematode C.elegans at 3.12-50 mg/mL. The essential oils of CA and LS have an important bioactive potential in their antioxidant, antibacterial and cytotoxicity activity. Both essential oils could possibly be used in the field of natural medicine, natural food preservation, cosmetics, sanitation and plaguicides among others.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Antineoplásicos/farmacologia , Antioxidantes/farmacologia , Cryptocarya/química , Óleos Voláteis/farmacologia , Extratos Vegetais/farmacologia , Animais , Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Caenorhabditis elegans/efeitos dos fármacos , Caenorhabditis elegans/crescimento & desenvolvimento , Proliferação de Células , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Células Tumorais Cultivadas
2.
Int J Mol Sci ; 20(11)2019 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-31185635

RESUMO

Small regulatory RNAs (sRNAs) are molecules that play an important role in the regulation of gene expression. sRNAs in bacteria can affect important processes, such as metabolism and virulence. Previous studies showed a significant role of sRNAs in the Vibrio species, but knowledge about Vibrio parahaemolyticus is limited. Here, we examined the conservation of sRNAs between V. parahaemolyticus and other human Vibrio species, in addition to investigating the conservation between V. parahaemolyticus strains differing in pandemic origin. Our results showed that only 7% of sRNAs were conserved between V. parahaemolyticus and other species, but 88% of sRNAs were highly conserved within species. Nonetheless, two sRNAs coding to RNA-OUT, a component of the Tn10/IS10 system, were exclusively present in pandemic strains. Subsequent analysis showed that both RNA-OUT were located in pathogenicity island-7 and would interact with transposase VPA1379, according to the model of pairing of IS10-encoded antisense RNAs. According to the location of RNA-OUT/VPA1379, we also investigated if they were expressed during infection. We observed that the transcriptional level of VPA1379 was significantly increased, while RNA-OUT was decreased at three hours post-infection. We suggest that IS10 transcription increases in pandemic strains during infection, probably to favor IS10 transposition and improve their fitness when they are facing adverse conditions.


Assuntos
Ilhas Genômicas , RNA não Traduzido/genética , Vibrio parahaemolyticus/genética , Células CACO-2 , Sequência Conservada , Humanos , Transposases/genética , Transposases/metabolismo , Vibrio parahaemolyticus/patogenicidade
3.
Rev Med Chil ; 142(5): 593-8, 2014 May.
Artigo em Espanhol | MEDLINE | ID: mdl-25427016

RESUMO

Obesity is a risk factor for cancer. Epidemiological evidences associate ovarian cancer with obesity. Epithelial ovarian cancer (EOC) is the most common type of ovarian cancer and accounts for a high rate of mortality. The association between ovarian cancer and obesity could be explained by molecular factors secreted by adipose tissue such as leptin. In EOC, leptin increases cell proliferation and inhibits apoptosis. Additionally, adipose tissue synthesizes endogenous estrogens, which increase cell proliferation of epithelial ovarian cells. Also, obesity associated hyperinsulinism could increase ovarian estrogen secretion.


Assuntos
Obesidade/complicações , Neoplasias Ovarianas/etiologia , Feminino , Humanos , Obesidade/metabolismo , Neoplasias Ovarianas/metabolismo
4.
Microorganisms ; 12(4)2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38674757

RESUMO

Vibrio parahaemolyticus is an important human pathogen that is currently the leading cause of shellfish-borne gastroenteritis in the world. Particularly, the pandemic strain has the capacity to induce cytotoxicity and enterotoxicity through its Type 3 Secretion System (T3SS2) that leads to massive cell death. However, the specific mechanism by which the T3SS2 induces cell death remains unclear and its contribution to mitochondrial stress is not fully understood. In this work, we evaluated the contribution of the T3SS2 of V. parahaemolyticus in generating mitochondrial stress during infection in human intestinal HT-29 cells. To evaluate the contribution of the T3SS2 of V. parahaemolyticus in mitochondrial stress, infection assays were carried out to evaluate mitochondrial transition pore opening, mitochondrial fragmentation, ATP quantification, and cell viability during infection. Our results showed that the Δvscn1 (T3SS2+) mutant strain contributes to generating the sustained opening of the mitochondrial transition pore. Furthermore, it generates perturbations in the ATP production in infected cells, leading to a significant decrease in cell viability and loss of membrane integrity. Our results suggest that the T3SS2 from V. parahaemolyticus plays a role in generating mitochondrial stress that leads to cell death in human intestinal HT-29 cells. It is important to highlight that this study represents the first report indicating the possible role of the V. parahaemolyticus T3SS2 and its effector proteins involvement in generating mitochondrial stress, its impact on the mitochondrial pore, and its effect on ATP production in human cells.

5.
Microorganisms ; 12(3)2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38543555

RESUMO

In recent studies, emphasis has been placed on the zonula occludens toxin (Zot) from the non-toxigenic Vibrio parahaemolyticus strain PMC53.7 as an agent inducing alterations in the actin cytoskeleton of infected Caco-2 cells and which appears as a relevant virulence factor. Universal zot primers were designed by the alignment of different types of zot gene and identification of conserved sequences to investigate the presence in diverse environmental and clinical V. parahaemolyticus isolates, in co-occurrence with virulence factors, such a hemolysins and secretion systems. The study screened a total of 390 isolates from environmental sources from Chile and Italy and 95 Chilean clinical isolates. The results revealed that around 37.2% of Chilean environmental strains and 25.9% of Italian strains, and 24.2% of clinical isolates carried the zot gene. The Zot-C2 cluster was present in 71.4% of Chilean environmental strains but absent in clinical isolates, while the Zot-C4 cluster was identified in 28.6% of environmental and 100% of clinical isolates. Understanding the role of zot in V. parahaemolyticus virulence is crucial, especially considering the risk associated with consuming diverse isolates from bivalves and the co-occurrence with virulence factors such as TDH, TRH or T3SS2.

6.
Microorganisms ; 12(3)2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38543581

RESUMO

In this study, bacterial isolates C1-4-7, D2-4-6, and M1-4-11 from Antarctic soil were phenotypically and genotypically characterized, and their antibacterial spectrum and that of cell-free culture supernatant were investigated. Finally, the effect of temperature and culture medium on the production of antimicrobial compounds was investigated. The three bacteria were identified as different strains of the genus Pseudomonas. The three bacteria were multi-drug resistant to antibiotics. They exhibited different patterns of growth inhibition of pathogenic bacteria. M1-4-11 was remarkable for inhibiting the entire set of pathogenic bacteria tested. All three bacteria demonstrated optimal production of antimicrobial compounds at 15 °C and 18 °C. Among the culture media studied, Nutrient broth would be the most suitable to promote the production of antimicrobial compounds. The thermostability exhibited by the antimicrobial molecules secreted, their size of less than 10 kDa, and their protein nature would indicate that these molecules are bacteriocin-like compounds.

7.
Foods ; 12(24)2023 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-38137300

RESUMO

Low fermentation temperatures are usually employed to obtain high-quality wines. This is especially interesting for white wine production since it prevents the loss of volatile compounds and a browning appearance; however, available fermentative yeasts do not usually tolerate low temperatures. Therefore, an interesting place to find new yeasts with cryotolerance is the Antarctic continent. From soil samples collected in Antarctica, 125 yeasts were isolated, of which 25 exhibited fermentative activity at 10 °C. After a fingerprinting assay, we classified the candidates into nine isotypes and sequenced internal transcribed spacer regions for their identification. These yeasts were identified as part of the Mrakia genus. Sugar and alcohol tolerance tests showed that some of these Antarctic soil yeasts were able to grow up to 9% alcohol, and 25% sugar was reached; however, they exhibited longer latency periods compared to the control Saccharomyces cerevisiae. The optimal growing temperature for the isolated Antarctic yeasts was between 10 °C and 15 °C. A comprehensive analysis of the results obtained showed that the isolates 10M3-1, 4M3-6, and 4B1-35 could be good candidates for fermentation purposes due to their alcohol, sugar tolerance, and growth features. Our results prove that it is possible to isolate fermentative yeasts from Antarctic soil with promising characteristics for their potential use in the wine production industry.

8.
Neurotox Res ; 42(1): 4, 2023 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-38103074

RESUMO

The gut-brain axis is an essential communication pathway between the central nervous system (CNS) and the gastrointestinal tract. The human microbiota is composed of a diverse and abundant microbial community that compasses more than 100 trillion microorganisms that participate in relevant physiological functions such as host nutrient metabolism, structural integrity, maintenance of the gut mucosal barrier, and immunomodulation. Recent evidence in animal models has been instrumental in demonstrating the possible role of the microbiota in neurodevelopment, neuroinflammation, and behavior. Furthermore, clinical studies suggested that adverse changes in the microbiota can be considered a susceptibility factor for neurological disorders (NDs), such as Alzheimer's disease (AD), Parkinson's disease (PD), Huntington's disease (HD), and amyotrophic lateral sclerosis (ALS). In this review, we will discuss evidence describing the role of gut microbes in health and disease as a relevant risk factor in the pathogenesis of neurodegenerative disorders, including AD, PD, HD, and ALS.


Assuntos
Doença de Alzheimer , Esclerose Lateral Amiotrófica , Microbioma Gastrointestinal , Doença de Huntington , Doenças Neurodegenerativas , Doença de Parkinson , Animais , Humanos , Eixo Encéfalo-Intestino , Microbioma Gastrointestinal/fisiologia , Doenças Neurodegenerativas/patologia , Sistema Nervoso Central , Doença de Parkinson/patologia , Doença de Huntington/patologia
9.
Acta Crystallogr C ; 67(Pt 11): m342-5, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22051949

RESUMO

In the title polymeric compound, [Cu(C(9)H(6)O(4))(C(3)H(4)N(2))(2)](n), the copper(II) cation occupies an N(2)O(3) coordination sphere defined by two 1H-imidazole (imid) ligands in trans positions and three carboxylate O atoms from three different 2-(carboxylatomethyl)benzoate (hpt(2-)) dianions. The geometry is that of a square pyramid with one of the O atoms at the apex, bridging neighbouring metal centres into an [-ON(2)CuO(2)CuN(2)O-] dinuclear unit. These units are in turn connected by hpt anions into a reticular mesh topologically characterized by two types of loops, viz. a four-membered Cu(2)O(2) diamond motif and a 32-membered Cu(4)O(8)C(20) ring. The imid groups do not take part in the formation of the two-dimensional structure, but take part in the N-H···O interactions. These arise only within individual planes, interplanar interactions being only of the van der Waals type.


Assuntos
Ânions/química , Metais/química , Compostos Organometálicos/química , Cristalografia por Raios X , Ligação de Hidrogênio , Ligantes , Modelos Moleculares
10.
Acta Crystallogr C ; 67(Pt 11): m367-70, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22051955

RESUMO

The title polymeric compound, {(C(13)H(16)N(2))[Co(C(10)H(3)O(8))(C(13)H(14)N(2))(H(2)O)(2)](2)·5H(2)O}(n), is an ionic structure comprising an anionic two-dimensional mesh characterized by a {[Co(Hbtc)(bpp)(H(2)O)(2)](-)}(2) motif [Hbtc is 5-carboxybenzene-1,2,4-tricarboxylate and bpp is 1,3-bis(4-pyridyl)propane], with interspersed 4,4'-(propane-1,3-diyl)dipyridinium cations, denoted (H(2)bpp)(2+), and water molecules providing the charge balance and structure stabilization. The reticular mesh consists of two independent types of [Co(H(2)O)(2)](2+) cationic nodes (lying on inversion centres), interconnected in the [101] direction by two independent sets of neutral bridging bpp ligands, both types of ligands being split by non-equivalent twofold axes. One set is formed by genuinely symmetric moieties, while those in the second set are only symmetric by disorder in the central propane bridge. These chains contain only one type of Co(II) centre and one type of bpp ligand; the metal cations therein are laterally bridged by Hbtc anions, thus forming transverse chains of alternating types of Co(II) cations. The elemental motif of the resulting grid is a highly distorted parallelogram, with metal-metal distances of 13.5242 (14) Å in the bpp direction and 9.105 (2) Å in the Hbtc direction, and a large internal angle of 138.42 (18)°. These two-dimensional structures have a profusion of hydrogen-bonding interactions with each other, either directly (with the aqua molecules as donors and the Hbtc anions as acceptors) or mediated by the unbound (H(2)bpp)(2+) cations and water molecules of hydration. These interactions generate a very complex hydrogen-bonding scheme involving all of the available N-H and O-H groups and which links these two-dimensional grids into a three-dimensional network.


Assuntos
Ânions/química , Compostos Organometálicos/química , Cristalografia por Raios X , Ligantes , Estrutura Molecular
11.
Acta Crystallogr C ; 67(Pt 5): m169-72, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21540537

RESUMO

The two isomorphous title compounds, [M(C(5)H(7)N(6))(2)(C(9)H(6)O(4))(2)(H(2)O)(2)]·4H(2)O or M(2+)(Hdap(+))(2)(hpt(2-))(2)(H(2)O)(2)·4H(2)O {where dap is 2,6-diaminopurine, H(2)hpt is homophthalic acid [2-(2-carboxyphenyl)acetic acid] and M is Ni(II) or Co(II)}, consist of neutral M(2+)(Hdap(+))(2)(hpt(2-))(2)(H(2)O)(2) monomers, where the M(II) cation lies on an inversion centre and its MN(2)O(4) octahedral environment is defined by one N atom (from Hdap(+)), two O atoms (from one hpt(2-) dianion and one water molecule) and their inversion images. The structures are unusual in that the Hdap(+) cation occurs in an uncommon protonated state (as 2,6-diamino-7H-purin-1-ium) and both ligands bind in an unprecedented monodentate fashion. The existence of a large number of donors and acceptors for hydrogen bonding, together with π-π interactions, leads to a rather complex three-dimensional structure.


Assuntos
2-Aminopurina/análogos & derivados , Cobalto/química , Complexos de Coordenação/química , Níquel/química , Compostos Organometálicos/química , Elementos de Transição/química , 2-Aminopurina/química , Cristalografia por Raios X , Ligação de Hidrogênio , Ligantes , Conformação Molecular , Estrutura Molecular
12.
Microorganisms ; 9(12)2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34946021

RESUMO

Carotenoids are highly important in pigmentation, and its content in farmed crustaceans and fish correlates to their market value. These pigments also have a nutritional role in aquaculture where they are routinely added as a marine animal food supplement to ensure fish development and health. However, there is little information about carotenoids obtained from Antarctic bacteria and its use for pigmentation improvement and flesh quality in aquaculture. This study identified carotenoids produced by Antarctic soil bacteria. The pigmented strain (CN7) was isolated on modified Luria-Bertani (LB) media and incubated at 4 °C. This Gram-negative bacillus was identified by 16S rRNA analysis as Flavobacterium segetis. Pigment extract characterization was performed through high-performance liquid chromatography (HPLC) and identification with liquid chromatography-mass spectrometry (LC-MS). HPLC analyses revealed that this bacterium produces several pigments in the carotenoid absorption range (six peaks). LC-MS confirms the presence of one main peak corresponding to lutein or zeaxanthin (an isomer of lutein) and several other carotenoid pigments and intermediaries in a lower quantity. Therefore, we propose CN7 strain as an alternative model to produce beneficial carotenoid pigments with potential nutritional applications in aquaculture.

13.
Genes (Basel) ; 11(10)2020 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-33092062

RESUMO

Ceriporiopsis subvermispora is a white-rot fungus with a high specificity towards lignin mineralization when colonizing dead wood or lignocellulosic compounds. Its lignocellulose degrading system is formed by cellulose hydrolytic enzymes, manganese peroxidases, and laccases that catalyze the efficient depolymerization and mineralization of lignocellulose. To determine if this metabolic specialization has modified codon usage of the lignocellulolytic system, improving its adaptation to the fungal translational machine, we analyzed the adaptation to host codon usage (CAI), tRNA pool (tAI, and AAtAI), codon pair bias (CPB), and the number of effective codons (Nc). These indexes were correlated with gene expression of C. subvermispora, in the presence of glucose and Aspen wood. General gene expression was not correlated with the index values. However, in media containing Aspen wood, the induction of expression of lignocellulose-degrading genes, showed significantly (p < 0.001) higher values of CAI, AAtAI, CPB, tAI, and lower values of Nc than non-induced genes. Cellulose-binding proteins and manganese peroxidases presented the highest adaptation values. We also identified an expansion of genes encoding glycine and glutamic acid tRNAs. Our results suggest that the metabolic specialization to use wood as the sole carbon source has introduced a bias in the codon usage of genes involved in lignocellulose degradation. This bias reduces codon diversity and increases codon usage adaptation to the tRNA pool available in C. subvermispora. To our knowledge, this is the first study showing that codon usage is modified to improve the translation efficiency of a group of genes involved in a particular metabolic process.


Assuntos
Uso do Códon , Lacase/metabolismo , Lignina/metabolismo , Peroxidases/metabolismo , Polyporales/metabolismo , RNA de Transferência/genética , Catálise , Hidrólise , Lacase/genética , Peroxidases/genética , Filogenia , Polyporales/genética , Polyporales/crescimento & desenvolvimento
14.
PLoS One ; 15(1): e0228178, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31978153

RESUMO

In recent years, multidrug resistance of Shigella strains associated with genetic elements like pathogenicity islands, have become a public health problem. The Shigella resistance locus pathogenicity island (SRL PAI) of S. flexneri 2a harbors a 16Kbp region that contributes to the multidrug resistance phenotype. However, there is not much information about other functions such as metabolic, physiologic or ecological ones. For that, wild type S. flexneri YSH6000 strain, and its spontaneous SRL PAI mutant, 1363, were used to study the contribution of the island in different growth conditions. Interestingly, when both strains were compared by the Phenotype Microarrays, the ability to metabolize D-aspartic acid as a carbon source was detected in the wild type strain but not in the mutant. When D-aspartate was added to minimal medium with other carbon sources such as mannose or mannitol, the SRL PAI-positive strain was able to metabolize it, while the SRL PAI-negative strain did not. In order to identify the genetic elements responsible for this phenotype, a bioinformatic analysis was performed and two genes belonging to SRL PAI were found: orf8, coding for a putative aspartate racemase, and orf9, coding for a transporter. Thus, it was possible to measure, by an indirect analysis of racemization activity in minimal medium supplemented only with D-aspartate, that YSH6000 strain was able to transform the D-form into L-, while the mutant was impaired to do it. When the orf8-orf9 region from SRL island was transformed into S. flexneri and S. sonnei SRL PAI-negative strains, the phenotype was restored. Although, when single genes were cloned into plasmids, no complementation was observed. Our results strongly suggest that the aspartate racemase and the transporter encoded in the SRL pathogenicity island are important for bacterial survival in environments rich in D-aspartate.


Assuntos
Isomerases de Aminoácido/metabolismo , Ácido D-Aspártico/metabolismo , Farmacorresistência Bacteriana Múltipla/genética , Ilhas Genômicas , Shigella flexneri/genética , Isomerases de Aminoácido/genética , Proteínas de Bactérias/metabolismo , Ácido D-Aspártico/análise , Genes Bacterianos , Manose/metabolismo , Fases de Leitura Aberta/genética , Fenótipo , Shigella flexneri/enzimologia , Shigella flexneri/crescimento & desenvolvimento , Shigella sonnei/genética
15.
Microbiol Resour Announc ; 9(21)2020 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-32439667

RESUMO

Here, we announce the draft genome sequence of Pseudomonas sp. strain AN3A02, isolated from the rhizosphere of one of the only two species of vascular plants existing in the Antarctic continent, Deschampsia antarctica Desv. This isolate, which inhibited the mycelial growth of Botrytis cinerea in dual culture, has a genome sequence of 6,778,644 bp, with a G+C content of 60.4%. These draft genome sequence data provide insight into the genetics underpinning the antifungal activity of this strain.

16.
Artigo em Inglês | MEDLINE | ID: mdl-33072618

RESUMO

Vibrio parahaemolyticus non-toxigenic strains are responsible for about 10% of acute gastroenteritis associated with this species, suggesting they harbor unique virulence factors. Zonula occludens toxin (Zot), firstly described in Vibrio cholerae, is a secreted toxin that increases intestinal permeability. Recently, we identified Zot-encoding genes in the genomes of highly cytotoxic Chilean V. parahaemolyticus strains, including the non-toxigenic clinical strain PMC53.7. To gain insights into a possible role of Zot in V. parahaemolyticus, we analyzed whether it could be responsible for cytotoxicity. However, we observed a barely positive correlation between Caco-2 cell membrane damage and Zot mRNA expression during PMC53.7 infection and non-cytotoxicity induction in response to purified PMC53.7-Zot. Unusually, we observed a particular actin disturbance on cells infected with PMC53.7. Based on this observation, we decided to compare the sequence of PMC53.7-Zot with Zot of human pathogenic species such as V. cholerae, Campylobacter concisus, Neisseria meningitidis, and other V. parahaemolyticus strains, using computational tools. The PMC53.7-Zot was compared with other toxins and identified as an endotoxin with conserved motifs in the N-terminus and a variable C-terminal region and without FCIGRL peptide. Notably, the C-terminal diversity among Zots meant that not all of them could be identified as toxins. Structurally, PMC53.7-Zot was modeled as a transmembrane protein. Our results suggested that it has partial 3D structure similarity with V. cholerae-Zot. Probably, the PMC53.7-Zot would affect the actin cytoskeletal, but, in the absence of FCIGRL, the mechanisms of actions must be elucidated.


Assuntos
Toxina da Cólera , Vibrio parahaemolyticus , Células CACO-2 , Campylobacter , Chile , Endotoxinas , Humanos , Vibrio parahaemolyticus/genética
17.
Acta Crystallogr C ; 65(Pt 1): m24-7, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19129593

RESUMO

The two isomorphous title structures, formulated as {[Co(C(10)H(4)O(8))(C(12)H(10)N(2))(H(2)O)(2)].C(12)H(10)N(2)}(n), (I), and {[Co(C(10)H(4)O(8))(C(12)H(12)N(2))(H(2)O)(2)].C(12)H(12)N(2)}(n), (II), respectively, are reported. They crystallize in the space group P\overline{1} with only one formula unit in the asymmetric unit, so that the organic ligands lie about inversion centres and the Co atom lies on an inversion centre. The Co atoms are octahedrally coordinated by a carboxylate O atom from 2,5-dicarboxybenzene-1,4-dicarboxylate (H(2)btc), one N atom from 1,2-di-4-pyridylethene (L) in (I) or from 1,2-di-4-pyridylethane (L) in (II), and one coordinated water molecule, plus their inversion-related species. This particular coordination results in a two-dimensional array, with an elemental unit in the shape of a parallelogram having the Co(II) cations at the corners, linked in one direction by L bridges and in the opposite direction by H(2)btc groups. The L solvent molecules act as pillars between parallel planes, linking them by strong hydrogen bonds where the H atoms lie midway between the formal donor/acceptor atoms in a ;shared' mode. Comparison is made with structures presenting the same structural motif, strongly suggesting that the two-dimensional arrangement reported here might be a very stable robust building block for molecular engineering purposes.


Assuntos
Cobalto/química , Compostos Organometálicos/química , Piridinas/química , Cristalografia , Estrutura Molecular
18.
Acta Crystallogr C ; 65(Pt 7): m241-5, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19578254

RESUMO

catena-Poly[[tetraaquabis(1H-pyrazole-kappaN(2))nickel(II)] [[diaquabis(1H-pyrazole-kappaN(2))nickel(II)]-mu-benzene-1,2,4,5-tetracarboxylato-kappa(2)O(1):O(4)] tetrahydrate], {[Ni(C(3)H(4)N(2))(2)(H(2)O)(4)][Ni(C(10)H(2)O(8))(C(3)H(4)N(2))(2)(H(2)O)(2)].4H(2)O}(n), (I), and poly[[(mu(4)-benzene-1,2,4,5-tetracarboxylato-kappa(4)O(1):O(2):O(4):O(5))octakis(1H-pyrazole-kappaN(2))dicobalt(II)] tetrahydrate], {[Co(2)(C(10)H(2)O(8))(C(3)H(4)N(2))(8)].4H(2)O}(n), (II), are polymeric compounds crystallizing in the space group P1, with two independent metallic cations and one benzene-1,2,4,5-tetracarboxylate (btc) anion, each lying on symmetry centres. Individual coordination polyhedra are regular and the main differences are in the way the btc anion binds [mu(2) in (I) and mu(4) in (II)], promoting a 'chain-like' one-dimensional structure in (I) and a 'sieve-like' two-dimensional motif in (II).


Assuntos
Benzoatos/química , Compostos Organometálicos/química , Polímeros/química , Cristalografia por Raios X , Ligantes , Modelos Moleculares , Níquel/química
19.
Acta Crystallogr C ; 65(Pt 7): m250-4, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19578256

RESUMO

(Mu-benzene-1,2,4,5-tetracarboxylato-kappa(2)O(1):O(4))bis[aquabis(2,2-methylpropane-1,3-diamine-kappa(2)N,N')nickel(II)] methanol disolvate tetrahydrate, [Ni(2)(C(10)H(2)O(8))(C(5)H(14)N(2))(4)(H(2)O)(2)].2CH(4)O.4H(2)O, (I), is dinuclear, with elemental units built up around an inversion centre halving the benzene-1,2,4,5-tetracarboxylate (btc) anion, which bridges two symmetry-related Ni(II) cations. The octahedral Ni polyhedron is completed by two chelating 2,2-methylpropane-1,3-diamine (dmpda) groups and a terminal aqua ligand. Two methanol and four water solvent molecules are involved in a number of N-H...O and O-H...O hydrogen bonds which define a strongly bound two-dimensional supramolecular structure. The structure of catena-poly[[[bis(2,2-methylpropane-1,3-diamine-kappa(2)N,N')nickel(II)]-mu-pyridine-2,5-dicarboxylato-kappa(3)O(5):N,O(2)-[(2,2-methylpropane-1,3-diamine-kappa(2)N,N')nickel(II)]-mu-pyridine-2,5-dicarboxylato-kappa(3)N,O(2):O(5)] octahydrate], {[Ni(2)(C(7)H(3)NO(4))(2)(C(5)H(14)N(2))(3)].8H(2)O}(n), (II), is polymeric, forming twisted chains around three independent Ni centres, two of which lie on inversion centres and the third in a general position. There are three chelating dmpda ligands (one disordered over two equally populated positions), which are each attached to a different cation, and two pyridine-2,5-dicarboxylate (pdc) anions, both chelating the Ni centre in general positions through an -O-C-C-N- loop, while acting as bridges to the remaining two centrosymmetric Ni atoms. There are, in addition, eight noncoordinated water molecules in the structure, some of which are disordered.


Assuntos
Benzoatos/química , Hidrocarbonetos Clorados/química , Níquel/química , Polímeros/química , Piridinas/química , Cristalografia por Raios X , Ligação de Hidrogênio , Ligantes , Estrutura Molecular
20.
Microbiol Resour Announc ; 8(22)2019 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31147434

RESUMO

We announce the draft genome sequence of Pseudomonas sp. strain M7D1, isolated from the rhizosphere of a plant in the Atacama Desert bloom event. The genome sequence had 6,170,633 bp with a G+C content of 59.9%. This draft genome sequence gives information about the presence of genes related to iron acquisition, alleviation of abiotic stress, and other essential traits of plant growth-promoting rhizobacteria.

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