Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 66
Filtrar
Más filtros

Bases de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Plant J ; 115(6): 1599-1618, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37277961

RESUMEN

Wounding stress leads to leaf senescence. However, the underlying molecular mechanism has not been elucidated. In this study, we investigated the role of the MdVQ10-MdWRKY75 module in wound-induced leaf senescence. MdWRKY75 was identified as a key positive modulator of wound-induced leaf senescence by activating the expression of the senescence-associated genes MdSAG12 and MdSAG18. MdVQ10 interacted with MdWRKY75 to enhance MdWRKY75-activated transcription of MdSAG12 and MdSAG18, thereby promoting leaf senescence triggered by wounding. In addition, the calmodulin-like protein MdCML15 promoted MdVQ10-mediated leaf senescence by stimulating the interaction between MdVQ10 and MdWRKY75. Moreover, the jasmonic acid signaling repressors MdJAZ12 and MdJAZ14 antagonized MdVQ10-mediated leaf senescence by weakening the MdVQ10-MdWRKY75 interaction. Our results demonstrate that the MdVQ10-MdWRKY75 module is a key modulator of wound-induced leaf senescence and provides insights into the mechanism of leaf senescence caused by wounding.


Asunto(s)
Malus , Malus/genética , Senescencia de la Planta , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Hojas de la Planta/genética , Hojas de la Planta/metabolismo , Regulación de la Expresión Génica de las Plantas
2.
New Phytol ; 243(3): 997-1016, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38849319

RESUMEN

Jasmonic acid (JA) and gibberellin (GA) coordinately regulate plant developmental programs and environmental cue responses. However, the fine regulatory network of the cross-interaction between JA and GA remains largely elusive. In this study, we demonstrate that MdNAC72 together with MdABI5 positively regulates anthocyanin biosynthesis through an exquisite MdNAC72-MdABI5-MdbHLH3 transcriptional cascade in apple. MdNAC72 interacts with MdABI5 to promote the transcriptional activation of MdABI5 on its target gene MdbHLH3 and directly activates the transcription of MdABI5. The MdNAC72-MdABI5 module regulates the integration of JA and GA signals in anthocyanin biosynthesis by combining with JA repressor MdJAZ2 and GA repressor MdRGL2a. MdJAZ2 disrupts the MdNAC72-MdABI5 interaction and attenuates the transcriptional activation of MdABI5 by MdNAC72. MdRGL2a sequesters MdJAZ2 from the MdJAZ2-MdNAC72 protein complex, leading to the release of MdNAC72. The E3 ubiquitin ligase MdSINA2 is responsive to JA and GA signals and promotes ubiquitination-dependent degradation of MdNAC72. The MdNAC72-MdABI5 interface fine-regulates the integration of JA and GA signals at the transcriptional and posttranslational levels by combining MdJAZ2, MdRGL2a, and MdSINA2. In summary, our findings elucidate the fine regulatory network connecting JA and GA signals with MdNAC72-MdABI5 as the core in apple.


Asunto(s)
Ciclopentanos , Regulación de la Expresión Génica de las Plantas , Giberelinas , Malus , Oxilipinas , Proteínas de Plantas , Transducción de Señal , Ubiquitinación , Oxilipinas/metabolismo , Malus/genética , Malus/metabolismo , Ciclopentanos/metabolismo , Ubiquitinación/efectos de los fármacos , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Giberelinas/metabolismo , Proteolisis/efectos de los fármacos , Antocianinas/metabolismo , Unión Proteica/efectos de los fármacos , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitina-Proteína Ligasas/genética , Modelos Biológicos
3.
J Integr Plant Biol ; 66(2): 265-284, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38284786

RESUMEN

Anthocyanins are secondary metabolites induced by environmental stimuli and developmental signals. The positive regulators of anthocyanin biosynthesis have been reported, whereas the anthocyanin repressors have been neglected. Although the signal transduction pathways of gibberellin (GA) and jasmonic acid (JA) and their regulation of anthocyanin biosynthesis have been investigated, the cross-talk between GA and JA and the antagonistic mechanism of regulating anthocyanin biosynthesis remain to be investigated. In this study, we identified the anthocyanin repressor MdbHLH162 in apple and revealed its molecular mechanism of regulating anthocyanin biosynthesis by integrating the GA and JA signals. MdbHLH162 exerted passive repression by interacting with MdbHLH3 and MdbHLH33, which are two recognized positive regulators of anthocyanin biosynthesis. MdbHLH162 negatively regulated anthocyanin biosynthesis by disrupting the formation of the anthocyanin-activated MdMYB1-MdbHLH3/33 complexes and weakening transcriptional activation of the anthocyanin biosynthetic genes MdDFR and MdUF3GT by MdbHLH3 and MdbHLH33. The GA repressor MdRGL2a antagonized MdbHLH162-mediated inhibition of anthocyanins by sequestering MdbHLH162 from the MdbHLH162-MdbHLH3/33 complex. The JA repressors MdJAZ1 and MdJAZ2 interfered with the antagonistic regulation of MdbHLH162 by MdRGL2a by titrating the formation of the MdRGL2a-MdbHLH162 complex. Our findings reveal that MdbHLH162 integrates the GA and JA signals to negatively regulate anthocyanin biosynthesis. This study provides new information for discovering more anthocyanin biosynthesis repressors and explores the cross-talk between hormone signals.


Asunto(s)
Ciclopentanos , Malus , Oxilipinas , Malus/genética , Malus/metabolismo , Antocianinas/metabolismo , Giberelinas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulación de la Expresión Génica de las Plantas
4.
Phys Rev Lett ; 131(20): 202502, 2023 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-38039451

RESUMEN

Traditional photonuclear reactions primarily excite giant dipole resonances, making the measurement of isovector giant resonances with higher multipolarities a great challenge. In this Letter, the manipulation of collective excitations of different multipole transitions in even-even nuclei via vortex γ photons is investigated. We develop the calculation method for photonuclear cross sections induced by the vortex γ photon beam using the fully self-consistent random-phase approximation plus particle-vibration coupling (RPA+PVC) model based on Skyrme density functional. We find that the electromagnetic transitions with multipolarity J<|m_{γ}| are forbidden for vortex γ photons due to the angular momentum conservation, with m_{γ} being the projection of total angular momentum of γ photon on its propagation direction. For instance, this allows for probing the isovector giant quadrupole resonance without interference from dipole transitions using vortex γ photons with m_{γ}=2. Furthermore, the electromagnetic transition with J=|m_{γ}|+1 vanishes at a specific polar angle. Therefore, the giant resonances with specific multipolarity can be extracted via vortex γ photons. Moreover, the vortex properties of γ photons can be meticulously diagnosed by measuring the nuclear photon-absorption cross section. Our method opens new avenues for photonuclear excitations, generation of coherent γ photon laser and precise detection of vortex particles, and consequently, has significant impact on nuclear physics, nuclear astrophysics and strong laser physics.

5.
Mediators Inflamm ; 2023: 2546278, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37396299

RESUMEN

Methods: Using a CRISPR/Cas9 gene-editing system, EFTUD2 single allele knockout HepG2.2.15 cells were constructed. Subsequently, the HBV biomarkers in EFTUD2+/- HepG2.2.15 cells and wild-type (WT) cells with or without IFN-α treatment were detected. And the EFTUD2-regulated genes were then identified using mRNA sequence. Selected gene mRNA variants and their proteins were examined by qRT-PCR and Western blotting. To confirm the effects of EFTUD2 on HBV replication and IFN-stimulated gene (ISG) expression, a rescue experiment in EFTUD2+/- HepG2.2.15 cells was performed by EFTUD2 overexpression. Results: IFN-induced anti-HBV activity was found to be restricted in EFTUD2+/- HepG2.2.15 cells. The mRNA sequence showed that EFTUD2 could regulate classical IFN and virus response genes. Mechanistically, EFTUD2 single allele knockout decreased the expression of ISG-encoded proteins, comprising Mx1, OAS1, and PKR (EIF2AK2), through mediated gene splicing. However, EFTUD2 did not affect the expression of Jak-STAT pathway genes. Furthermore, EFTUD2 overexpression could restore the attenuation of IFN anti-HBV activity and the reduction of ISG resulting from EFTUD2 single allele knockout. Conclusion: EFTUD2, the spliceosome factor, is not IFN-inducible but is an IFN effector gene. EFTUD2 mediates IFN anti-HBV effect through regulation of gene splicing for certain ISGs, including Mx1, OAS1, and PKR. EFTUD2 does not affect IFN receptors or canonical signal transduction components. Therefore, it can be concluded that EFTUD2 regulates ISGs using a novel, nonclassical mechanism.


Asunto(s)
Quinasas Janus , Empalmosomas , Humanos , Células Hep G2 , Virus de la Hepatitis B/genética , ARN Mensajero/genética , Transducción de Señal , Factores de Transcripción STAT , Replicación Viral
6.
J Ind Microbiol Biotechnol ; 50(1)2023 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-37327079

RESUMEN

The chemo-enzymatic and enzymatic synthesis of heparan sulfate and heparin are considered as an attractive alternative to the extraction of heparin from animal tissues. Sulfation of the hydroxyl group at position 2 of the deacetylated glucosamine is a prerequisite for subsequent enzymatic modifications. In this study, multiple strategies, including truncation mutagenesis based on B-factor values, site-directed mutagenesis guided by multiple sequence alignment, and structural analysis were performed to improve the stability and activity of human N-sulfotransferase. Eventually, a combined variant Mut02 (MBP-hNST-NΔ599-602/S637P/S741P/E839P/L842P/K779N/R782V) was successfully constructed, whose half-life at 37°C and catalytic activity were increased by 105-fold and 1.35-fold, respectively. After efficient overexpression using the Escherichia coli expression system, the variant Mut02 was applied to N-sulfation of the chemically deacetylated heparosan. The N-sulfation content reached around 82.87% which was nearly 1.88-fold higher than that of the wild-type. The variant Mut02 with high stability and catalytic efficiency has great potential for heparin biomanufacturing.


Asunto(s)
Sulfatos , Sulfotransferasas , Animales , Humanos , Sulfotransferasas/genética , Sulfotransferasas/química , Sulfotransferasas/metabolismo , Heparina
7.
Plant J ; 106(5): 1414-1430, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33759251

RESUMEN

Jasmonate (JA) induces the biosynthesis of anthocyanin and proanthocyanidin. MdMYB9 is essential for modulating the accumulation of both anthocyanin and proanthocyanidin in apple, but the molecular mechanism for induction of anthocyanin and proanthocyanidin biosynthesis by JA is unclear. In this study, we discovered an apple telomere-binding protein (MdTRB1) to be the interacting protein of MdMYB9. A series of biological assays showed that MdTRB1 acted as a positive modulator of anthocyanin and proanthocyanidin accumulation, and is dependent on MdMYB9. MdTRB1 interacted with MdMYB9 and enhanced the activation activity of MdMYB9 to its downstream genes. In addition, we found that the JA signaling repressor MdJAZ1 interacted with MdTRB1 and interfered with the interaction between MdTRB1 and MdMYB9, therefore negatively modulating MdTRB1-promoted biosynthesis of anthocyanin and proanthocyanidin. These results show that the JAZ1-TRB1-MYB9 module dynamically modulates JA-mediated accumulation of anthocyanin and proanthocyanidin. Taken together, our data further expand the functional study of TRB1 and provide insights for further studies of the modulation of anthocyanin and proanthocyanidin biosynthesis by JA.


Asunto(s)
Acetatos/farmacología , Antocianinas/metabolismo , Ciclopentanos/farmacología , Malus/genética , Oxilipinas/farmacología , Reguladores del Crecimiento de las Plantas/farmacología , Proantocianidinas/metabolismo , Proteínas de Unión a Telómeros/metabolismo , Secuencia de Aminoácidos , Regulación de la Expresión Génica de las Plantas , Malus/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente , Alineación de Secuencia , Proteínas de Unión a Telómeros/genética
8.
J Exp Bot ; 73(3): 980-997, 2022 01 27.
Artículo en Inglés | MEDLINE | ID: mdl-34555166

RESUMEN

Abscisic acid is involved in the regulation of cold stress response, but its molecular mechanism remains to be elucidated. In this study, we demonstrated that the APETALA2/ethylene responsive factor (AP2/ERF) family protein MdABI4 positively regulates abscisic acid-mediated cold tolerance in apple. We found that MdABI4 interacts with MdICE1, a key regulatory protein involved in the cold stress response, and enhances the transcriptional regulatory function of MdICE1 on its downstream target gene MdCBF1, thus improving abscisic acid-mediated cold tolerance. The jasmonate-ZIM domain (JAZ) proteins MdJAZ1 and MdJAZ2 negatively modulate MdABI4-improved cold tolerance in apple by interacting with the MdABI4 protein. Further investigation showed that MdJAZ1 and MdJAZ2 interfere with the interaction between the MdABI4 and MdICE1 proteins. Together, our data revealed that MdABI4 integrates jasmonic acid and abscisic acid signals to precisely modulate cold tolerance in apple through the JAZ-ABI4-ICE1-CBF regulatory cascade. These findings provide insights into the crosstalk between jasmonic acid and abscisic acid signals in response to cold stress.


Asunto(s)
Malus , Proteínas de Plantas , Factores de Transcripción , Ácido Abscísico/metabolismo , Regulación de la Expresión Génica de las Plantas , Malus/genética , Malus/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Transducción de Señal/genética , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
9.
Immunol Invest ; 51(5): 1485-1497, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34436958

RESUMEN

BACKGROUND: The elongation factor Tu GTP-binding domain-containing 2 gene (EFTUD2) participates in antiviral immune responses. However, the association between genetic polymorphisms of EFTUD2 and hepatitis B virus (HBV) infection susceptibility has not been well-studied. We analyzed the relationship between single nucleotide polymorphisms (SNPs) of EFTUD2 and HBV infection susceptibility and clarified the potential function. METHODS: In total, 448 control subjects and 379 patients with chronic HBV infection from Zhangjiagang First People's Hospital (Jiangsu, China) were enrolled. Sequenom iPLEX assay was used to detect genotypes of four SNPs (rs1071682, rs2277617, rs2289674, and rs3809756). Dual-luciferase reporter vectors with wild-type A and mutant-type C alleles of EFTUD2 rs3809756 were transfected into HepG2 cells to explore effects on transcription activity. RESULTS: Only rs3809756 was significantly associated with HBV infection susceptibility (P < .05). The risk of HBV infection was higher in individuals carrying the rs3809756-CC genotype than in those carrying the rs3809756-AA genotype (odds ratio [OR] = 1.945, 95% confidence interval [CI] = 1.129-3.351, P = .017). Subgroup analysis based on the dominant model revealed that rs3809756-AC and rs3809756-CC carriers had a significantly higher risk of HBV infection than rs3809756-AA carriers among patients who were male (OR = 1.732, 95% CI = 1.218-2.464, P = .002), were aged ≥47 years (OR = 1.502, 95% CI = 1.050-2.148, P = .026), or without liver cirrhosis (OR = 1.407, 95% CI = 1.077-1.838, P = .012). In the dual-luciferase reporter assay, the relative luciferase activity of rs3809756-C was significantly lower than that of rs3809756-A (P < .05). CONCLUSION: EFTUD2 rs3809756A>C was associated with HBV infection susceptibility and might be involved in the downregulation of promoter activity.


Asunto(s)
Hepatitis B Crónica , Hepatitis B , Alelos , Estudios de Casos y Controles , Femenino , Frecuencia de los Genes , Predisposición Genética a la Enfermedad , Genotipo , Guanosina Trifosfato , Hepatitis B/genética , Virus de la Hepatitis B , Hepatitis B Crónica/complicaciones , Hepatitis B Crónica/genética , Humanos , Masculino , Factor Tu de Elongación Peptídica/genética , Factores de Elongación de Péptidos/genética , Polimorfismo de Nucleótido Simple , Ribonucleoproteína Nuclear Pequeña U5/genética
10.
Zhongguo Zhong Yao Za Zhi ; 47(9): 2449-2456, 2022 May.
Artículo en Zh | MEDLINE | ID: mdl-35531692

RESUMEN

The optimal prescription of tanshinone Ⅱ_A(TSN)-glycyrrhetinic acid(GA) solid lipid nanoparticles(GT-SLNs) was explored and evaluated in vivo and in vitro, and its effect on acne after oral administration was investigated. The preparation processing and prescription were optimized and verified by single factor and response surface methodology. The in vitro release of GA and TSN in GT-SLNs was determined by ultra-performance liquid chromatography(UPLC). The effect of GT-SLNs on acne was investigated by the levels of sex hormones in mice, ear swelling model, and tissue changes in sebaceous glands, and the pharmacokinetics was evaluated. The 24-hour cumulative release rates of GA and TSN in SLNs were 65.87%±5.63% and 36.13%±2.31% respectively. After oral administration of GT-SLNs and the mixture of GA and TSN(GT-Mix), the AUC_(0-t) and AUC_(0-∞) of TSN in GT-SLNs were 1.98 times and 4.77 times those in the GT-Mix group, respectively, and the peak concentration of TSN in the GT-SLNs group was 17.2 times that in the GT-Mix group. After intragastric administration of GT-SLNs, the serum levels of testosterone(T) and the ratio of testosterone to estradiol(T/E2) in the GT-SLNs group significantly declined, and the sebaceous glands of mice were atrophied to a certain extent. The results demonstrated that obtained GT-SLNs with good encapsulation efficiency and uniform particle size could promote the release of GA and TSN. GT-SLNs displayed therapeutic efficacy on acne manifested by androgen increase, abnormal sebaceous gland secretion, and inflammatory damage.


Asunto(s)
Acné Vulgar , Ácido Glicirretínico , Nanopartículas , Abietanos , Acné Vulgar/tratamiento farmacológico , Animales , Portadores de Fármacos , Liposomas , Ratones , Tamaño de la Partícula , Testosterona
11.
Psychosom Med ; 83(9): 995-1003, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34420000

RESUMEN

OBJECTIVE: This study aimed to examine the association of subjective and objective sleep quality with subsequent peptic ulcer rebleeding among older patients. METHODS: Of 1196 older patients with peptic ulcer bleeding (PUB) recruited from 12 grade A hospitals in the People's Republic of China, 1106 achieved full recovery from PUB, and they were followed up for up to 30 days. Using multiple measures at 1-week intervals, patients who presented PUB symptoms were invited to have an esophagogastroduodenoscopy examination. Subjective sleep quality was measured using the Pittsburgh Sleep Quality Index. Objective sleep quality domains were measured using an accelerometer, including sleep onset latency, sleep efficiency, total sleep time, and the number of awakenings. RESULTS: This study documented a 30-day cumulative ulcer rebleeding rate of 15.3%. Multivariate analyses showed that longer sleep onset latency (hazard ratio [HR] = 2.136 [1.336-2.558]) and more nighttime awakenings (HR = 1.698 [1.169-2.666]) increased the risk of ulcer rebleeding. However, a longer total sleep time (HR = 0.768 [0.698-0.887]) and better sleep efficiency (HR = 0.795 [0.682-0.975]) protected against ulcer rebleeding. Older patients who perceived poorer sleep quality were also more likely to experience ulcer rebleeding (HR = 2.295 [1.352-3.925]). CONCLUSIONS: The present results highlight the importance of proper treatment and prevention of sleep problems in older adults after successful PUB treatment. Our results, if replicable in future studies with more rigorous design and representative samples, might shed light on the etiology of ulcer rebleeding and suggest new pathways for preventing this disease.


Asunto(s)
Úlcera Péptica , Calidad del Sueño , Anciano , Humanos , Úlcera Péptica/complicaciones , Úlcera Péptica/epidemiología , Úlcera Péptica Hemorrágica/etiología , Úlcera Péptica Hemorrágica/terapia , Recurrencia , Factores de Riesgo
12.
Virol J ; 18(1): 105, 2021 05 29.
Artículo en Inglés | MEDLINE | ID: mdl-34051803

RESUMEN

BACKGROUND: Hepatitis B virus (HBV) is a DNA virus belonging to the Hepadnaviridae family that has limited tissue and species specificity. Due to the persistence of HBV covalently closed circular DNA (cccDNA) in host cells after HBV infection, current antiviral drugs cannot eradicate HBV. Therefore, the development of an active cell culture system supporting HBV infection has become the key to studying HBV and developing effective therapeutic drugs. MAIN BODY: This review summarizes the significant research achievements in HBV cell culture systems in vitro, including embryonic hepatocytes and primary hepatocytes, which support the virus infection process most similar to that in the body and various liver tumor cells. The discovery of the bile-acid pump sodium-taurocholate co-transporting polypeptide (NTCP) as the receptor of HBV has advanced our understanding of HBV biology. Subsequently, various liver cancer cells overexpressing NTCP that support HBV infection have been established, opening a new door for studying HBV infection. The fact that induced pluripotent stem cells that differentiate into hepatocyte-like cells support HBV infection provides a novel idea for the establishment of an HBV cell culture system. CONCLUSION: Because of the host and tissue specificity of HBV, a suitable in vitro HBV infection system is critical for the study of HBV pathogenesis. Nevertheless, recent advances regarding HBV infection in vitro offer hope for better studying the biological characteristics of HBV, the pathogenesis of hepatitis B, the screening of anti-HBV drugs and the mechanism of carcinogenesis.


Asunto(s)
Virus de la Hepatitis B , Hepatitis B , Replicación Viral , Células Hep G2 , Hepatitis B/tratamiento farmacológico , Virus de la Hepatitis B/fisiología , Hepatocitos/virología , Humanos
13.
Psychosom Med ; 82(2): 197-207, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31794441

RESUMEN

OBJECTIVE: This study aimed to examine the association between social isolation, change in severity of depression, and subsequent recurrence of peptic ulcer disease (PUD) in older adults with mild cognitive impairment. METHODS: Older adults (≥55 years) with mild cognitive impairment and Helicobacter pylori-infected PUD (N = 2208) were recruited between 2010 and 2014 from 12 hospitals in the People's Republic of China. H. pylori was eradicated and PUD was cleared in 2015 participants by the end of 2014; 1900 of these were followed up for up to 36 months. The Kaplan-Meier method was used to assess how PUD recurrence varied with social engagement levels and changes in depression severity. Multivariate Cox proportional hazard models were used to examine associations between social isolation, changes in depression severity, and PUD recurrence. RESULTS: PUD recurrence was more prevalent in socially isolated (10.8%) than in socially engaged participants (5.5%). However, the rates of PUD were lower in socially isolated individuals without (absence of) depression (7.2%) and those with decreased depression (8.2%), whereas socially isolated individuals with unchanged and increased depression had substantially higher rates of PUD (16.3% and 17.8%, respectively; the social isolation by depression group for PUD recurrence was significant (p < .001). Specifically, although social isolation was associated with PUD recurrence during the 36-month follow-up period (hazard ratio [HR] = 2.665 [1.602-4.518]), it did not increase PUD recurrence risk in participants without depression or with reduced depression. However, in participants with unchanged or increased depression, PUD recurrence was more likely to occur in socially isolated (HR = 1.587 [1.125-2.588]; HR = 1.886 [1.012, 3.522] respectively) than in socially engaged participants. CONCLUSIONS: Social isolation is associated with a greater risk of PUD recurrence; however, the absence of or decreased severity of depression may alter this relationship.


Asunto(s)
Envejecimiento/psicología , Disfunción Cognitiva/fisiopatología , Depresión/fisiopatología , Úlcera Péptica/fisiopatología , Aislamiento Social/psicología , Anciano , Anciano de 80 o más Años , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Recurrencia , Riesgo , Índice de Severidad de la Enfermedad
14.
Microb Pathog ; 145: 104186, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32272213

RESUMEN

BACKGROUND: Lactobacillus brevis is a major contaminant of spoiled beer. And it was able to enter VBNC state and cause false negative detection, which poses a major challenge to the brewing industry. METHODS: The genomic DNA of L. brevis BM-LB13908 was extracted and purified to form a sequencing library that meets the quality requirements and was sequenced. The sequencing results were then screened and assembled to obtain the entire genome sequence of L. brevis. Predicted genes were annotated by GO database, KEGG pathway database and COG functional classification system. RESULTS: The final assembly yielded 275 scaffolds of a total length of 2 840 080 bp with a G + C content of 53.35%. There were 2357, 701, 1519 predicted genes with corresponding GO functional, COG functional, and KEGG biological pathway annotations, respectively. The genome of L. brevis BM-LB13908 contains hop resistance gene horA and multiple genes related to the formation of VBNC state. CONCLUSIONS: This report describes the draft genome sequence of L. brevis BM-LB13908, a spoilage strain isolated from finished beer sample. This study may support further study on L. brevis and other beer spoilage bacteria, and prevent and control beer spoilage caused by microorganisms.


Asunto(s)
Levilactobacillus brevis , Bacterias , Cerveza , Microbiología de Alimentos , Genómica , Levilactobacillus brevis/genética
15.
Angew Chem Int Ed Engl ; 59(49): 21959-21964, 2020 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-32797653

RESUMEN

A ruthenium-catalyzed formal anti-Markovnikov hydroamination of allylic alcohols for the synthesis of chiral γ-amino alcohols is presented. Proceeding via an asymmetric hydrogen-borrowing process, the catalysis allows racemic secondary allylic alcohols to react with various amines, affording enantiomerically enriched chiral γ-amino alcohols with broad substrate scope and excellent enantioselectivities (68 examples, up to >99 % ee).

16.
Angew Chem Int Ed Engl ; 58(31): 10528-10536, 2019 07 29.
Artículo en Inglés | MEDLINE | ID: mdl-31162782

RESUMEN

A practical method for the synthesis of α-chiral amines by alkylation of amines with alcohols in the absence of any transition-metal catalysts has been developed. Under the co-catalysis of a ketone and NaOH, racemic secondary alcohols reacted with Ellman's chiral tert-butanesulfinamide by a hydrogen autotransfer process to afford chiral amines with high diastereoselectivities (up to >99:1). Broad substrate scope and up to a 10 gram scale production of chiral amines were demonstrated. The method was applied to the synthesis of chiral deuterium-labelled amines with high deuterium incorporation and optical purity, including examples of chiral deuterated drugs. The configuration of amine products is found to be determined solely by the configuration of the chiral tert-butanesulfinamide regardless of that of alcohols, and this is corroborated by DFT calculations. Further mechanistic studies showed that the reaction is initiated by the ketone catalyst and involves a transition state similar to that proposed for the Meerwein-Ponndorf-Verley (MPV) reduction, and importantly, it is the interaction of the sodium cation of the base with both the nitrogen and oxygen atoms of the sulfinamide moiety that makes feasible, and determines the diastereoselectivity of, the reaction.

17.
Plant Cell Environ ; 41(11): 2678-2692, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-29940702

RESUMEN

Phytohormone abscisic acid (ABA) induces anthocyanin biosynthesis; however, the underlying molecular mechanism is less known. In this study, we found that the apple MYB transcription factor MdMYB1 activated anthocyanin biosynthesis in response to ABA. Using a yeast screening technique, we isolated MdbZIP44, an ABA-induced bZIP transcription factor in apple, as a co-partner with MdMYB1. MdbZIP44 promoted anthocyanin accumulation in response to ABA by enhancing the binding of MdMYB1 to the promoters of downstream target genes. Furthermore, we identified MdBT2, a BTB protein, as an MdbZIP44-interacting protein. A series of molecular, biochemical, and genetic analysis suggested that MdBT2 degraded MdbZIP44 protein through the Ubiquitin-26S proteasome system, thus inhibiting MdbZIP44-modulated anthocyanin biosynthesis. Taken together, we reveal a novel working mechanism of MdbZIP44-mediated anthocyanin biosynthesis in response to ABA.


Asunto(s)
Ácido Abscísico/fisiología , Antocianinas/metabolismo , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/metabolismo , Malus/metabolismo , Reguladores del Crecimiento de las Plantas/fisiología , Proteínas de Plantas/metabolismo , Ácido Abscísico/metabolismo , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/genética , Ensayo de Cambio de Movilidad Electroforética , Malus/genética , Filogenia , Reguladores del Crecimiento de las Plantas/metabolismo , Proteínas de Plantas/genética , Plantas Modificadas Genéticamente , Alineación de Secuencia , Transcriptoma , Técnicas del Sistema de Dos Híbridos
18.
Microb Pathog ; 115: 154-158, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29278782

RESUMEN

OBJECTIVE: This study aimed to investigate correlation and in vitro mechanism of bactericidal activity on E. coli with whey protein isolate (WPI) during ultrasonic treatment. METHODS: The structural changes of WPI under ultrasonic field were studied by amino-acid analyzer, circular dichroism, SDS-PAGE, and spectrophotometer. RESULTS: With the increasing of WPI concentration added during ultrasonic treatment, the survival rate of E. coli increased. The influence of WPI on bactericidal activity under ultrasonic treatment might due to the change of tertiary and higher level structures, not by the primary structure, and had little relation with secondary structure. CONCLUSION: The influence of WPI on bactericidal activity during ultrasonic treatment might due to the change of the tertiary structure and higher level structures.


Asunto(s)
Antibacterianos/farmacología , Escherichia coli/efectos de los fármacos , Ondas Ultrasónicas , Proteína de Suero de Leche/farmacología , Secuencia de Aminoácidos , Estructura Secundaria de Proteína
19.
Microb Pathog ; 120: 213-218, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29730518

RESUMEN

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). This article has been retracted at the request of the authors. There is significant discrepancy in the genomic characteristics between the currently and previously dominant GBS (2018) and previously dominant GBS (2013-2014). The dramatically rapid and unexpected evolution of GBS strains has led to the significant discrepancy from recent findings which makes all the authors strongly concerned that this will influence the accuracy and validity of GBS treatment and therapy if based on the current manuscript. For example, the genomic difference between the currently prevalent type (II and III) and previously prevalent type (III) is considerably diverse, for which the pathogenic and virulent characteristics of the strains are very different. As all authors have a strong sense of responsibility and expertise in clinical microbiology, agreed by all authors, on behalf of all authors of this manuscript, the authors consequently request for article withdrawal for this manuscript.


Asunto(s)
Genotipo , Serogrupo , Infecciones Estreptocócicas/epidemiología , Infecciones Estreptocócicas/microbiología , Streptococcus agalactiae/genética , Streptococcus agalactiae/aislamiento & purificación , Streptococcus agalactiae/patogenicidad , China/epidemiología , Humanos , Lactante , Recién Nacido , Meningitis/epidemiología , Meningitis/microbiología , Tipificación de Secuencias Multilocus , Reacción en Cadena de la Polimerasa Multiplex , Neumonía/epidemiología , Neumonía/microbiología , Prevalencia , Sepsis/epidemiología , Sepsis/microbiología
20.
Physiol Plant ; 164(3): 279-289, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29527680

RESUMEN

It is known that ethylene signaling is involved in the regulation of the salt stress response. However, the molecular mechanism of ethylene-regulated salt stress tolerance remains largely unclear. In this study, an apple NAM ATAF CUC transcription factor, MdNAC047, was isolated and functionally characterized to be involved in ethylene-modulated salt tolerance. MdNAC047 gene was significantly induced by salt treatment and its overexpression conferred increased tolerance to salt stress and facilitated the release of ethylene. Quantitative real-time-PCR analysis demonstrated that overexpression of MdNAC047 increased the expression of ethylene-responsive genes. Electrophoretic mobility shift assay, yeast one-hybrid and dual-luciferase assays suggested that MdNAC047 directly binds to the MdERF3 (ETHYLENE RESPONSE FACTOR) promoter and activates its transcription. In addition, genetic analysis assays indicated that MdNAC047 regulates ethylene production at least partially in an MdERF3-dependent pathway. Overall, we found a novel 'MdNAC047-MdERF3-ethylene-salt tolerance' regulatory pathway, which provide new insight into the link between ethylene and salt stress.


Asunto(s)
Etilenos/metabolismo , Malus/metabolismo , Proteínas de Plantas/metabolismo , Ensayo de Cambio de Movilidad Electroforética , Regulación de la Expresión Génica de las Plantas/genética , Regulación de la Expresión Génica de las Plantas/fisiología , Malus/efectos de los fármacos , Malus/genética , Proteínas de Plantas/genética , Tolerancia a la Sal , Estrés Fisiológico/efectos de los fármacos , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA