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1.
Mol Plant Microbe Interact ; 34(1): 62-74, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33021883

RESUMEN

Ciboria shiraiana causes hypertrophy sorosis scleroteniosis in mulberry trees, resulting in huge economic losses, and exploring its pathogenic mechanism at a genomic level is important for developing new control methods. Here, genome sequencing of C. shiraiana based on PacBio RSII and Illumina HiSeq 2500 platform as well as manual gap filling was performed. Synteny analysis with Sclerotinia sclerotiorum revealed 16 putative chromosomes corresponding to 16 chromosomes of C. shiraiana. Screening of rapid-evolution genes revealed that 97 and 2.4% of genes had undergone purifying selection and positive selection, respectively. When compared with S. sclerotiorum, fewer secreted effector proteins were found in C. shiraiana. The number of genes involved in pathogenicity, including secondary metabolites, carbohydrate active enzymes, and P450s, in the C. shiraiana genome was comparable with that of other necrotrophs but higher than that of biotrophs and saprotrophs. The growth-related genes and plant cell-wall-degradation-related genes in C. shiraiana were expressed in different developmental and infection stages, and may be potential targets for prevention and control of this pathogen. These results provide new insights into C. shiraiana pathogenic mechanisms, especially host range and necrotrophy features, and lay the foundation for further study of the underlying molecular mechanisms.[Formula: see text] The author(s) have dedicated the work to the public domain under the Creative Commons CC0 "No Rights Reserved" license by waiving all of his or her rights to the work worldwide under copyright law, including all related and neighboring rights, to the extent allowed by law.


Asunto(s)
Ascomicetos , Genoma Fúngico , Enfermedades de las Plantas , Ascomicetos/genética , Genoma Fúngico/genética , Hipertrofia/microbiología , Morus/microbiología , Enfermedades de las Plantas/genética
2.
Hum Genomics ; 11(1): 4, 2017 03 16.
Artículo en Inglés | MEDLINE | ID: mdl-28302172

RESUMEN

BACKGROUND: A growing number of severe Mycoplasma pneumoniae pneumonia (MPP) cases have been reported recently. However, the pathogenesis of severe MPP is not clear. In the current study, transcriptome sequencing was used to identify gene expression and alternative splicing profiles to provide insights into the pathogenesis of severe MPP. METHODS: RNAs of bronchoalveolar lavage fluid (BALF) samples from three severe MPP children and three mild MPP children were analyzed respectively by deep sequencing followed by computational annotation and quantification. RESULTS: The gene expression analysis revealed 14 up-regulated and 34 down-regulated genes in severe MPP children comparing to mild MPP children. The top 10 most up-regulated genes were IGHV1-69, CH17-472G23.1, ATP1B2, FCER2, MUC21, IL13, FCRLB, CLEC5A, FAM124A, and INHBA. The top 10 most down-regulated genes were OSTN-AS1, IL22RA2, COL3A1, C1orf141, IGKV2-29, RP11-731F5.2, IGHV4-4, KIRREL, DNASE1L3, and COL6A2. Clustering analysis revealed similar expression pattern of CLEC5A, IL13, FCER2, and FLT1. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses revealed changes related to primary immunodeficiency in severe MPP children comparing to mild MPP children; the pathway involves CD19, TNFRSF13C, CD79A, and AICDA genes. Among the differentially expressed genes, significant alternative splicing events were found in FCER2 and FCRLA. CONCLUSIONS: The current study on RNA sequencing provides novel insights into the pathogenesis of severe MPP in terms of gene expression and alternative splicing. The up-regulation of IL13, FCER2, FLT1, and CLEC5A and the down-regulation of CD79A, AICDA, CD19, and TNFRSF13C may contribute to the pathogenesis of severe MPP. The differential expressions of FCER2 and FCRLA could be due to their alternative splicing.


Asunto(s)
Líquido del Lavado Bronquioalveolar/química , Mycoplasma pneumoniae/fisiología , Neumonía por Mycoplasma/genética , Neumonía por Mycoplasma/inmunología , Transcriptoma , Empalme Alternativo , Femenino , Perfilación de la Expresión Génica , Regulación de la Expresión Génica , Humanos , Masculino , Neumonía por Mycoplasma/microbiología
3.
Wei Sheng Wu Xue Bao ; 57(3): 388-98, 2017 Mar 04.
Artículo en Zh | MEDLINE | ID: mdl-29756437

RESUMEN

Objective: We studied the biological and the epidemiological characteristics of the pathogen of hypertrophy sorosis scleroteniosis, which is a devastating fungal disease of mulberry. Methods: We studied the asexual and sexual reproductive phase stages of C. shiraiana, including the infection ability of hyphal, dormancy of sclerotia, the structures, release, number and germination of ascospores from apothecia, as well as the phenology of sclerotial germination. Results: In C. shiraiana, hyphae had no infection ability toward the female flowers of mulberry. Sclerotia of C. shiraiana must undergo cold treatment above 6 weeks, then the dormancy-breaking sclerotia could germinate to apothecia. One to fifteen apothecia were germinated from one sclerotium, and the number of ascospores in a 1.5 cm diameter apothecia could contain up to (5.6-6.3)×107. Ascospore C. shiraiana had significantly higher germination rates in acid than in neutral and alkaline environments. From late January to middle April, sclerotia germinated to apothecia, and got the highest value in the middle of March. Conclusion: C. shiraiana is a formidable pathogen to cause epidemic disease and damage in mulberry.


Asunto(s)
Ascomicetos/crecimiento & desarrollo , Morus/microbiología , Enfermedades de las Plantas/microbiología , Ascomicetos/clasificación , Ascomicetos/genética , Ascomicetos/aislamiento & purificación , Hifa/clasificación , Hifa/genética , Hifa/crecimiento & desarrollo , Hifa/aislamiento & purificación , Esporas Fúngicas/clasificación , Esporas Fúngicas/genética , Esporas Fúngicas/crecimiento & desarrollo , Esporas Fúngicas/aislamiento & purificación
4.
Sheng Wu Gong Cheng Xue Bao ; 38(1): 386-395, 2022 Jan 25.
Artículo en Zh | MEDLINE | ID: mdl-35142144

RESUMEN

Cutinase can degrade aliphatic and aromatic polyesters, as well as polyethylene terephthalate. Lack of commercially available cutinase calls for development of cost-effective production of efficient cutinase. In this study, eight cutinase genes were cloned from Sclerotinia sclerotiorum. The most active gene SsCut-52 was obtained by PCR combined with RT-PCR, expressed in Escherichia coli BL21 and purified by Ni-NTA affinity chromatography to study its characteristics and pathogenicity. Sscut-52 had a total length of 768 bp and 17 signal peptides at the N terminals. Phylogenetic analysis showed that its amino acid sequence had the highest homology with Botrytis keratinase cutinase and was closely related to Rutstroemia cutinase. Sscut-52 was highly expressed during the process of infecting plants by Sclerotinia sclerotiorum. Moreover, the expression level of Sscut-52 was higher than those of other cutinase genes in the process of sclerotia formation from mycelium. The heterologously expressed cutinase existed in the form of inclusion body. The renatured SsCut-52 was active at pH 4.0-10.0, and mostly active at pH 6.0, with a specific activity of 3.45 U/mg achieved. The optimum temperature of SsCut-52 was 20-30 ℃, and less than 60% of the activity could be retained at temperatures higher than 50 ℃. Plant leaf infection showed that SsCut-52 may promote the infection of Banlangen leaves by Sclerotinia sclerotiorum.


Asunto(s)
Ascomicetos , Ascomicetos/genética , Hidrolasas de Éster Carboxílico , Clonación Molecular , Filogenia
5.
Bioorg Med Chem Lett ; 21(4): 1113-7, 2011 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-21273073

RESUMEN

The host-guest inclusion system of ethyl substituted ß-cyclodextrin (DE-ß-CD) with mangiferin (MA) was investigated by fluorescence spectra in solution. The results showed that the MA was encapsulated in the DE-ß-CD's cavity to form a 2:1 stoichiometry host-guest inclusion complex (DE-ß-CD/MA) and the inclusion constant (K=3.04×10(6)L(2)/mol(2)) was confirmed by the typical double reciprocal plots. Furthermore, several experimental conditions were optimized in order to obtain the maximum fluorescence signal. In addition, the thermodynamic parameters, Gibbs free energy (ΔG°), enthalpy change (ΔH°) and entropy change (ΔS°) of DE-ß-CD/MA were obtained by the Van't Hoff equation. A spectrofluorimetric method for the determination of MA in solution in the presence of DE-ß-CD was developed based on the remarkable enhancement of the fluorescence intensity of MA. The linear range was 2.00×10(-8)-7.00×10(-6)mol/L and the detection limit was 4.05×10(-9)mol/L. The proposed method was successfully applied to the analysis of MA in serum with the satisfactory result.


Asunto(s)
beta-Ciclodextrinas/química , Humanos , Concentración de Iones de Hidrógeno , Conformación Molecular , Espectrometría de Fluorescencia , Termodinámica , Xantonas/análisis , Xantonas/química , beta-Ciclodextrinas/síntesis química , beta-Ciclodextrinas/farmacología
6.
Front Immunol ; 9: 1403, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29967623

RESUMEN

BACKGROUND: Mycoplasma pneumoniae pneumonia (MPP) is one of the most common community-acquired pneumonia; this study is to explore the immune-pathogenesis of children MPP. METHODS: Next-generation transcriptome sequencing was performed on the bronchoalveolar lavage fluid cells from six children with MPP and three children with foreign body aspiration as control. Some of the results had been validated by quantitative real-time PCR in an expanded group of children. RESULTS: Results revealed 810 differentially expressed genes in MPP group comparing to control group, of which 412 genes including RLTPR, CARD11 and RASAL3 were upregulated. These upregulated genes were mainly enriched in mononuclear cell proliferation and signaling biological processes. Kyoto encyclopedia of genes and genomes pathway analysis revealed that hematopoietic cell linage pathway, natural killer cell-mediated cytotoxicity pathway, and T cell receptor signaling pathway were significantly upregulated in MPP children. In addition, significant alternative splicing events were found in GNLY and SLC11A1 genes, which may cause the differential expressions of these genes. CONCLUSION: Our results suggest that NK and CD8+ T cells are over activated and proliferated in MPP children; the upregulated IFNγ, PRF1, GZMB, FASL, and GNLY may play important roles in the pathogenesis of children MPP.

7.
Sci Rep ; 7(1): 12934, 2017 10 11.
Artículo en Inglés | MEDLINE | ID: mdl-29021577

RESUMEN

Early distinction between severe Mycoplasma pneumoniae pneumonia (MPP) and mild MPP is still difficult. The aim of this study was to analyze cytokines in bronchoalveolar lavage fluid (BALF) and explore predicting factors of severe MPP in children. Retrospective analysis was performed on 150 children with MPP or bronchial foreign body (FB) admitted in our hospital. The mRNA levels of IL17A were found significantly lower in severe MPP group comparing with mild MPP group or FB group. However, no significant difference was found in the levels of IL4, IL10 or interferon beta1 (IFNß1) between the two groups. Receiver operator characteristic (ROC) curve analysis showed that IL17A can be used to distinguish severe MPP from mild MPP. These results were confirmed in a validation cohort including 40 MPP children from another hospital. IL17A levels were correlated with some clinical characters, such as refractoriness and pleural effusion. Lower IL17A levels were more likely to be found in refractory MPP children or in MPP children with pleural effusion. Moreover, the protein levels of IL17A in BALF were also found greatly decreased in children with severe MPP. Thus, decreased IL17A levels in BALF may be a valuable biomarker to identify severe MPP in children.


Asunto(s)
Interleucina-17/metabolismo , Mycoplasma pneumoniae/fisiología , Neumonía por Mycoplasma/metabolismo , Neumonía por Mycoplasma/microbiología , Índice de Severidad de la Enfermedad , Líquido del Lavado Bronquioalveolar , Niño , Preescolar , Citocinas/genética , Citocinas/metabolismo , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Neumonía por Mycoplasma/patología , Valor Predictivo de las Pruebas , Pronóstico , ARN Mensajero/genética , ARN Mensajero/metabolismo , Curva ROC
8.
PLoS One ; 11(6): e0157414, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27276057

RESUMEN

[This corrects the article DOI: 10.1371/journal.pone.0155814.].

9.
PLoS One ; 11(5): e0155814, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27213624

RESUMEN

A small, multigene family encodes 4-coumarate:CoA ligases (4CLs) that catalyze the ligation of CoA to hydroxycinnamic acids, a branch point directing metabolites to flavonoid or monolignol pathways. In this study, we characterized four 4CL genes from M. notabilis Genome Database, and cloned four Ma4CL genes from M. atropurpurea cv. Jialing No.40. A tissue-specific expression analysis indicated that Ma4CL3 was expressed at higher levels than the other genes, and that Ma4CL3 was strongly expressed in root bark, stem bark, and old leaves. Additionally, the expression pattern of Ma4CL3 was similar to the trend of the total flavonoid content throughout fruit development. A phylogenetic analysis suggested that Mn4CL1, Mn4CL2, and Mn4CL4 belong to class I 4CLs, and Mn4CL3 belongs to class II 4CLs. Ma4CL genes responded differently to a series of stresses. Ma4CL3 expression was higher than that of the other Ma4CL genes following wounding, salicylic acid, and ultraviolet treatments. An in vitro enzyme assay indicated that 4-coumarate acid was the best substrate among cinnamic acid, 4-coumarate acid, and caffeate acid, but no catalytic activity to sinapate acid and ferulate acid. The results of subcellular localization experiments showed that Ma4CL3 localized to the cytomembrane, where it activated transcription. We used different vectors and strategies to fuse Ma4CL3 with stilbene synthase (STS) to construct four Ma4CL-MaSTS co-expression systems to generate resveratrol. The results indicated that only a transcriptional fusion vector, pET-Ma4CL3-T-MaSTS, which utilized a T7 promoter and lac operator for the expression of MaSTS, could synthesize resveratrol.


Asunto(s)
Clonación Molecular/efectos de los fármacos , Coenzima A Ligasas/genética , Coenzima A Ligasas/metabolismo , Morus/enzimología , Ácidos Cumáricos/metabolismo , Regulación de la Expresión Génica de las Plantas , Morus/genética , Familia de Multigenes , Filogenia , Corteza de la Planta/metabolismo , Hojas de la Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Tallos de la Planta/metabolismo , Propionatos , Especificidad por Sustrato
10.
PLoS One ; 10(3): e0122081, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25822202

RESUMEN

Although ethylene is well known as an essential regulator of fruit development, little work has examined the role ethylene plays in the development and maturation of mulberry (Morus L.) fruit. To study the mechanism of ethylene action during fruit development in this species, we measured the ethylene production, fruit firmness, and soluble solids content (SSC) during fruit development and harvest. By comparing the results with those from other climacteric fruit, we concluded that Morus fruit are probably climacteric. Genes associated with the ethylene signal transduction pathway of Morus were characterized from M. notabilis Genome Database, including four ethylene receptor genes, a EIN2-like gene, a CTR1-like gene, four EIN3-like genes, and a RTE1-like gene. The expression patterns of these genes were analyzed in the fruit of M. atropurpurea cv. Jialing No.40. During fruit development, transcript levels of MaETR2, MaERS, MaEIN4, MaRTE, and MaCTR1 were lower at the early stages and higher after 26 days after full bloom (DAF), while MaETR1, MaEIL1, MaEIL2, and MaEIL3 remained constant. In ripening fruit, the transcripts of MaACO1 and MaACS3 increased, while MaACS1 and MaACO2 decreased after harvest. The transcripts of MaACO1, MaACO2, and MaACS3 were inhibited by ethylene, and 1-MCP (1-methylcyclopropene) upregulated MaACS3. The transcripts of the MaETR-like genes, MaRTE, and MaCTR1 were inhibited by ethylene and 1-MCP, suggesting that ethylene may accelerate the decline of MaETRs transcripts. No significant changes in the expression of MaEIN2, MaEIL1, and MaEIL3 were observed during ripening or in response to ethylene, while the expressions of MaEIL2 and MaEIL4 increased rapidly after 24 h after harvest (HAH) and were upregulated by ethylene. The present study provides insights into ethylene biosynthesis and signal transduction in Morus plants and lays a foundation for the further understanding of the mechanisms underlying Morus fruit development and ripening.


Asunto(s)
Etilenos/biosíntesis , Morus/fisiología , Proteínas de Plantas/genética , Frutas/crecimiento & desarrollo , Frutas/metabolismo , Perfilación de la Expresión Génica , Regulación del Desarrollo de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Morus/metabolismo , Transducción de Señal
11.
Gene ; 565(2): 221-7, 2015 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-25865297

RESUMEN

A cellulase gene (KJ700939, CsCelA) from Ciboria shiraiana that is highly expressed during the infection of mulberry fruit was screened by quantitative real-time PCR (qRT-PCR). Using cDNA isolated from infected mulberry fruits as template, the full-length 1170-bp sequence of CsCelA was obtained, which encodes a 390-amino acid protein with a putative signal peptide of 24 amino acids. The 998-bp fragment encoding the mature peptide of CsCelA was cloned into the multiple cloning site of the pPIC9K vector and overexpressed as an active protein of 55.3kDa in the methylotrophic yeast Pichia pastoris. The specific activity of induced supernatants of the recombinant cellulase (CsCelA) was 17.44U/ml and 135U/g for freeze-dried powder. The Kmax and Vmax of CsCelA for sodium carboxymethylcellulose (CMC) were 4.6mg/ml and 107.2U/mg, respectively. The supernatant and freeze-dried powder of the recombinant cellulase exhibited stable activity from pH4.0 to 9.0, and at temperatures ranging from 30°C to 55°C. Finally, the activity of the recombinant cellulase was assessed by enzymatic hydrolysis of the cell walls of mulberry leaves. CsCelA showed an endo-cellulase mode of cleavage, as assessed by thin layer chromatography (TLC).


Asunto(s)
Celulasa/genética , Hipertrofia/genética , Secuencia de Aminoácidos , Secuencia de Bases , Pared Celular/genética , Clonación Molecular , ADN Complementario/genética , Hidrólisis , Morus/genética , Pichia/genética , Hojas de la Planta/genética
12.
J Zhejiang Univ Sci B ; 15(7): 611-23, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25001221

RESUMEN

1-Aminocyclopropane-1-carboxylic acid synthase (ACS) and 1-aminocyclopropane-1-carboxylic acid oxidase (ACO) are encoded by multigene families and are involved in fruit ripening by catalyzing the production of ethylene throughout the development of fruit. However, there are no reports on ACS or ACO genes in mulberry, partly because of the limited molecular research background. In this study, we have obtained five ACS gene sequences and two ACO gene sequences from Morus Genome Database. Sequence alignment and phylogenetic analysis of MaACO1 and MaACO2 showed that their amino acids are conserved compared with ACO proteins from other species. MaACS1 and MaACS2 are type I, MaACS3 and MaACS4 are type II, and MaACS5 is type III, with different C-terminal sequences. Quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) expression analysis showed that the transcripts of MaACS genes were strongly expressed in fruit, and more weakly in other tissues. The expression of MaACO1 and MaACO2 showed different patterns in various mulberry tissues. MaACS and MaACO genes demonstrated two patterns throughout the development of mulberry fruit, and both of them were strongly up-regulated by abscisic acid (ABA) and ethephon.


Asunto(s)
Aminoácido Oxidorreductasas/genética , Liasas/genética , Morus/enzimología , Aminoácido Oxidorreductasas/química , Secuencia de Aminoácidos , Liasas/química , Datos de Secuencia Molecular , Filogenia , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Alineación de Secuencia
13.
Artículo en Inglés | MEDLINE | ID: mdl-21339082

RESUMEN

The supramolecular interaction of MAH-ß-cyclodextrin (MAH-ß-CD, a modified ß-cyclodextrin carrying seven vinyl carboxylic acid groups) and meferamic acid (MF) has been studied by spectrofluorimetry. The results showed that MAH-ß-CD reacted with MF to form a host-guest complex (MAH-ß-CD-MF) with stoichiometry (1:1) and the inclusion constant (K=7.15×10(2) L/mol) was ascertained by the typical double reciprocal plots. From the phase-solubility diagram, an increase in the water solubility of the drug was observed and the apparent stability constant (K(1:1)) was calculated to be 8.62×10(2) L/mol. Furthermore, the thermodynamic parameters (ΔG°, ΔH° and ΔS°) of MAH-ß-CD-MF were obtained and the inclusion mechanism was also preliminarily discussed. In order to further confirm the experimental results, investigation on the molecular modeling was performed. On the basis of the significant enhancement of the fluorescence intensity of MF, a spectrofluorimetric method for MF determination in bulk aqueous solution in the presence of MAH-ß-CD was developed. The linear range was 2.00×10(-8)-9.00×10(-5) mol/L and the detection limit was 3.36×10(-9) mol/L. The proposed method was successfully applied to determine MF in tablets, serum and urine with the satisfactory result.


Asunto(s)
Espectrometría de Fluorescencia/métodos , beta-Ciclodextrinas/análisis , beta-Ciclodextrinas/química , Ácidos/sangre , Ácidos/química , Ácidos/orina , Tampones (Química) , Humanos , Concentración de Iones de Hidrógeno , Cinética , Modelos Moleculares , Solubilidad , Soluciones , Comprimidos , Termodinámica , Factores de Tiempo
14.
Spectrochim Acta A Mol Biomol Spectrosc ; 81(1): 397-403, 2011 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-21757399

RESUMEN

An inclusion complex between the agrochemical chloropropham (CIPC) and ß-cyclodextrin (ß-CD) was prepared. A 2:1 host-guest stoichiometry was conformed by elemental analysis. From the phase solubility studies, the calculated stepwise stability constants were K(1)=224.6L/mol and K(2)=939.2L/mol, respectively. FT-IR, thermoanalysis and (1)H NMR spectra were applied to characterize the complex. It was speculated that the inclusion mode was two ß-CD cavities included the chlorophenyl and the isopropyl moiety of one CIPC molecule, which was in agreement with the most predominant configuration optimized by molecular modeling. By complexation with ß-CD, the water solubility and the thermal stability of CIPC were prominently improved.


Asunto(s)
Clorprofam/química , Sustancias Macromoleculares/química , Sustancias Macromoleculares/síntesis química , Modelos Moleculares , beta-Ciclodextrinas/química , Precipitación Química , Clorprofam/metabolismo , Simulación por Computador , Interacciones Farmacológicas , Herbicidas/química , Herbicidas/metabolismo , Espectroscopía de Resonancia Magnética , Modelos Biológicos , Transición de Fase , Solubilidad , Espectroscopía Infrarroja por Transformada de Fourier , Termogravimetría , beta-Ciclodextrinas/metabolismo
15.
J Comput Chem ; 23(16): 1642-55, 2002 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-12395430

RESUMEN

The GeH(n) (n = 0-4) and Ge(2)H(n) (n = 0-6) systems have been studied systematically by five different density functional methods. The basis sets employed are of double-zeta plus polarization quality with additional s- and p-type diffuse functions, labeled DZP++. For each compound plausible energetically low-lying structures were optimized. The methods used have been calibrated against a comprehensive tabulation of experimental electron affinities (Chemical Reviews 102, 231, 2002). The geometries predicted in this work include yet unknown anionic species, such as Ge(2)H(-), Ge(2)H(2)(-), Ge(2)H(3)(-), Ge(2)H(4)(-), and Ge(2)H(5)(-). In general, the BHLYP method predicts the geometries closest to the few available experimental structures. A number of structures rather different from the analogous well-characterized hydrocarbon radicals and anions are predicted. For example, a vinylidene-like GeGeH(2) (-) structure is the global minimum of Ge(2)H(2) (-). For neutral Ge(2)H(4), a methylcarbene-like HGë-GeH(3) is neally degenerate with the trans-bent H(2)Ge=GeH(2) structure. For the Ge(2)H(4) (-) anion, the methylcarbene-like system is the global minimum. The three different neutral-anion energy differences reported in this research are: the adiabatic electron affinity (EA(ad)), the vertical electron affinity (EA(vert)), and the vertical detachment energy (VDE). For this family of molecules the B3LYP method appears to predict the most reliable electron affinities. The adiabatic electron affinities after the ZPVE correction are predicted to be 2.02 (Ge(2)), 2.05 (Ge(2)H), 1.25 (Ge(2)H(2)), 2.09 (Ge(2)H(3)), 1.71 (Ge(2)H(4)), 2.17 (Ge(2)H(5)), and -0.02 (Ge(2)H(6)) eV. We also reported the dissociation energies for the GeH(n) (n = 1-4) and Ge(2)H(n) (n = 1-6) systems, as well as those for their anionic counterparts. Our theoretical predictions provide strong motivation for the further experimental study of these important germanium hydrides.

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