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1.
Artículo en Inglés | MEDLINE | ID: mdl-38863365

RESUMEN

OBJECTIVES: Pseudomonas aeruginosa and Acinetobacter baumannii are ranked as top-priority organisms by WHO. Antimicrobial peptides (AMPs) are promising antimicrobial agents that are highly effective against serious bacterial infections. METHODS: In our previous study, a series of α-helical AMPs were screened using a novel multiple-descriptor strategy. The current research suggested that S24 exhibited strong antimicrobial activity against major pathogenic bacteria, and displayed minimal haemolysis, good serum stability and maintained salt resistance. RESULTS: We found that S24 exerted an antimicrobial effect by destroying outer membrane permeability and producing a strong binding effect on bacterial genomic DNA that inhibits genomic DNA migration. Furthermore, S24 exerted a strong ability to promote healing in wound infected by P. aeruginosa, A. baumannii and mixed strains in a mouse model. CONCLUSIONS: Overall, S24 showed good stability under physiological conditions and excellent antimicrobial activity, suggesting it may be a potential candidate for the development of serious bacterial infection treatment.

2.
Crit Rev Microbiol ; : 1-14, 2023 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-37074732

RESUMEN

Live biotherapeutic product (LBP), a type of biological product, holds promise for the prevention or treatment of metabolic disease and pathogenic infection. Probiotics are live microorganisms that improve the intestinal microbial balance and beneficially affect the health of the host when ingested in sufficient numbers. These biological products possess the advantages of inhibition of pathogens, degradation of toxins, and modulation of immunity. The application of LBP and probiotic delivery systems has attracted great interest to researchers. The initial used technologies for LBP and probiotic encapsulation are traditional capsules and microcapsules. However, the stability and targeted delivery capability require further improved. The specific sensitive materials can greatly improve the delivery efficiency of LBPs and probiotics. The specific sensitive delivery systems show advantages over traditional ones due to their better properties of biocompatibility, biodegradability, innocuousness, and stability. Moreover, some new technologies, including layer-by-layer encapsulation, polyelectrolyte complexation, and electrohydrodynamic technology, show great potential in LBP and probiotic delivery. In this review, novel delivery systems and new technologies of LBPs and probiotics were presented, and the challenges and prospects were explored in specific sensitive materials for LBP and probiotic delivery.

3.
Environ Res ; 211: 112984, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35245534

RESUMEN

The Coronavirus Disease 2019 (COVID-19) lockdown policy reduced anthropogenic emissions and impacted the atmospheric chemical characteristics in Chinese urban cities. However, rare studies were conducted at the high mountain site. In this work, in-situ measurements of light absorption by carbonaceous aerosols and carbon dioxide (CO2) concentrations were conducted at Waliguan (WLG) over the northeastern Tibetan Plateau of China from January 3 to March 30, 2020. The data was employed to explore the influence of the COVID-19 lockdown on atmospheric chemistry in the background-free troposphere. During the sampling period, the light absorption near-infrared (>470 nm) was mainly contributed by BC (>72%), however, BC and brown carbon (BrC) contributed equally to light absorption in the short wavelength (∼350 nm). The average BC concentrations in the pre-, during and post-lockdown were 0.28 ±â€¯0.25, 0.18 ±â€¯0.16, and 0.28 ±â€¯0.20 µg m-3, respectively, which decreased by approximately 35% during the lockdown period. Meanwhile, CO2 also showed slight decreases during the lockdown period. The declined BC was profoundly attributed to the reduced emissions (∼86%), especially for the combustion of fossil fuels. Moreover, the declined light absorption of BC, primary and secondary BrC decreased the solar energy absorbance by 35, 15, and 14%, respectively. The concentration weighted trajectories (CWT) analysis suggested that the decreased BC and CO2 at WLG were exclusively associated with the emission reduction in the eastern region of WLG. Our results highlighted that the reduced anthropogenic emissions attributed to the lockdown in the urban cities did impact the atmospheric chemistry in the free troposphere of the Tibetan Plateau.


Asunto(s)
Contaminantes Atmosféricos , COVID-19 , Aerosoles/análisis , Contaminantes Atmosféricos/análisis , COVID-19/epidemiología , COVID-19/prevención & control , Dióxido de Carbono/análisis , China/epidemiología , Control de Enfermedades Transmisibles , Monitoreo del Ambiente , Humanos , Material Particulado/análisis , Hollín/análisis
4.
Appl Opt ; 60(20): 5900-5905, 2021 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-34263811

RESUMEN

A high-power continuous-wave (CW) ultraviolet (UV) laser at 378 nm from an intracavity frequency-doubled Alexandrite laser has been demonstrated with 638 nm fiber-coupled laser diodes as the pump source. A maximum output power of 2.55 W was obtained, which is the highest power for CW frequency-doubled Alexandrite lasers, to the best of our knowledge, corresponding to the optical-to-optical conversion efficiency of 7.9% from 638 nm pump laser to 378 nm UV laser. The beam quality factors M2 were measured to be 2.19 and 2.47 in x and y directions at UV output power of 1 W, respectively.

5.
Appl Environ Microbiol ; 86(20)2020 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-32801183

RESUMEN

Inthomycins belong to a growing family of oxazole-containing polyketides and exhibit a broad spectrum of anti-oomycete and herbicidal activities. In this study, we purified inthomycins A and B from the metabolites of Streptomyces sp. strain SYP-A7193 and determined their chemical structures. Genome sequencing, comparative genomic analysis, and gene disruption of Streptomyces sp. SYP-A7193 showed that the inthomycin biosynthetic gene cluster (itm) belonged to the hybrid polyketide synthase (PKS)/nonribosomal peptide synthetase (NRPS) system. Functional domain comparison and disruption/complementation experiments of itm12 resulted in the complete loss of inthomycins A and B and the subsequent restoration of their production, confirming that itm12 encodes a discrete acyltransferase (AT), and hence, itm was considered to belong to the trans-AT type I PKS system. Moreover, the disruption/complementation experiments of itm15 also resulted in the loss and restoration of inthomycin A and B formation. Further gene cloning, expression, purification, and activity verification of itm15 revealed that Itm15 is a cyclodehydratase that catalyzes a straight-chain dehydration reaction to form an oxazole ring for the biosynthesis of inthomycins A and B. Thus, we discovered a novel enzyme that catalyzes oxazole ring formation and elucidated the complete biosynthetic pathway of inthomycins.IMPORTANCEStreptomyces species produce numerous secondary metabolites with diverse structures and pharmacological activities that are beneficial for human health and have several applications in agriculture. In this study, hybrid nonribosomal peptide synthetase/polyketide synthase metabolites inthomycins A and B were isolated from after fermenting Streptomyces sp. SYP-A7193. Genome sequencing, gene disruption, gene complementation, heterologous expression, and activity assay revealed that the biosynthesis gene assembly line of inthomycins A and B was a 95.3-kb trans-AT type I PKS system in the strain SYP-A7193. More importantly, Itm15, a cyclodehydratase, was identified to be an oxazole ring formation enzyme required for the biosynthesis of inthomycins A and B; it is significant to discover this catalyzation reaction in the PKS/NRPS system in the field of microbiology. Our findings could provide further insights into the diversity of trans-AT type I PKS systems and the mechanism of oxazole cyclization involved in the biosynthesis of natural products.


Asunto(s)
Ácidos Grasos Insaturados/química , Genes Bacterianos , Familia de Multigenes , Oxazoles/metabolismo , Streptomyces/genética , Ácidos Grasos Insaturados/aislamiento & purificación , Oxazoles/química , Oxazoles/aislamiento & purificación , Streptomyces/química , Streptomyces/metabolismo
6.
BMC Microbiol ; 20(1): 143, 2020 06 03.
Artículo en Inglés | MEDLINE | ID: mdl-32493249

RESUMEN

BACKGROUND: Streptomycetes from the rhizospheric soils are a rich resource of novel secondary metabolites with various biological activities. However, there is still little information related to the isolation, antimicrobial activity and biosynthetic potential for polyketide and non-ribosomal peptide discovery associated with the rhizospheric streptomycetes of Panax notoginseng. Thus, the aims of the present study are to (i) identify culturable streptomycetes from the rhizospheric soil of P. notoginseng by 16S rRNA gene, (ii) evaluate the antimicrobial activities of isolates and analyze the biosynthetic gene encoding polyketide synthases (PKSs) and nonribosomal peptide synthetases (NRPSs) of isolates, (iii) detect the bioactive secondary metabolites from selected streptomycetes, (iv) study the influence of the selected isolate on the growth of P. notoginseng in the continuous cropping field. This study would provide a preliminary basis for the further discovery of the secondary metabolites from streptomycetes isolated from the rhizospheric soil of P. notoginseng and their further utilization for biocontrol of plants. RESULTS: A total of 42 strains representing 42 species of the genus Streptomyces were isolated from 12 rhizospheric soil samples in the cultivation field of P. notoginseng and were analyzed by 16S rRNA gene sequencing. Overall, 40 crude cell extracts out of 42 under two culture conditions showed antibacterial and antifungal activities. Also, the presence of biosynthesis genes encoding type I and II polyketide synthase (PKS I and PKS II) and nonribosomal peptide synthetases (NRPSs) in 42 strains were established. Based on characteristic chemical profiles screening by High Performance Liquid Chromatography-Diode Array Detector (HPLC-DAD), the secondary metabolite profiles of strain SYP-A7257 were evaluated by High Performance Liquid Chromatography-High Resolution Mass Spectrometry (HPLC-HRMS). Finally, four compounds actinomycin X2 (F1), fungichromin (F2), thailandin B (F7) and antifungalmycin (F8) were isolated from strain SYP-A7257 by using chromatography techniques, UV, HR-ESI-MS and NMR, and their antimicrobial activities against the test bacteria and fungus were also evaluated. In the farm experiments, Streptomyces sp. SYP-A7257 showed healthy growth promotion and survival rate improvement of P. notoginseng in the continuous cropping field. CONCLUSIONS: We demonstrated the P. notoginseng rhizospheric soil-derived Streptomyces spp. distribution and diversity with respect to their metabolic potential for polyketides and non-ribosomal peptides, as well as the presence of biosynthesis genes PKS I, PKS II and NRPSs. Our results showed that cultivatable Streptomyces isolates from the rhizospheric soils of P. notoginseng have the ability to produce bioactive secondary metabolites. The farm experiments suggested that the rhizospheric soil Streptomyces sp. SYP-A7257 may be a potential biological control agent for healthy growth promotion and survival rate improvement of P. notoginseng in the continuous cropping field.


Asunto(s)
Panax notoginseng/microbiología , Péptido Sintasas/genética , Sintasas Poliquetidas/genética , Streptomyces/clasificación , Proteínas Bacterianas/genética , Cromatografía Líquida de Alta Presión , ADN Bacteriano/genética , ADN Ribosómico/genética , Dactinomicina/análogos & derivados , Dactinomicina/aislamiento & purificación , Farmacorresistencia Bacteriana , Macrólidos/aislamiento & purificación , Filogenia , Polienos/aislamiento & purificación , ARN Ribosómico 16S/genética , Rizosfera , Metabolismo Secundario , Microbiología del Suelo , Streptomyces/genética , Streptomyces/aislamiento & purificación
7.
Opt Lett ; 45(16): 4389-4392, 2020 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-32796965

RESUMEN

A stable, 22.9 W, 671 nm single-frequency laser using a type II noncritically phase-matched external-cavity frequency doubling is demonstrated. The output power of the fundamental laser is 32.1 W; the corresponding conversion efficiency of frequency doubling from 1342 to 671 nm is calculated to be 71.3%. The M2 factors are measured to be 1.10 and 1.08 in the x and y directions, respectively. To the best of our knowledge, 22.9 W is the highest power obtained for a 671 nm single-frequency laser.

8.
Int J Syst Evol Microbiol ; 70(5): 3162-3166, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32250241

RESUMEN

An endophytic member of the genus Trichoderma was isolated from the root of a healthy 3-year-old Panax notoginseng in Yunnan province, PR China. The results of phylogenetic analyses based on a combined of ITS, tef1 and rpb2 indicated that this isolate was distinct from other species of the genus Trichoderma and closely related to Trichoderma songyi. It can be distinguished from T. songyi by its slower growth rates on PDA and colony morphology. The novel isolate formed conidia in thick white pustules scattered mostly at the margin. Its conidiophores tended to be regularly verticillium-like, little branched, sometimes substituted by phialides singly or in whorls. Conidia are smooth, mostly broadly subglobose to ellipsoidal. In combination with the genotypic and phenotypic characteristics, all data demonstrated that the fungus studied represented a unique and distinguishable novel species of the genus Trichoderma, for which the name Trichoderma panacis sp. nov. is proposed.


Asunto(s)
Panax notoginseng/microbiología , Filogenia , Trichoderma/clasificación , China , ADN de Hongos/genética , Endófitos/clasificación , Endófitos/aislamiento & purificación , Técnicas de Tipificación Micológica , Raíces de Plantas/microbiología , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Esporas Fúngicas/crecimiento & desarrollo , Trichoderma/aislamiento & purificación
9.
Acta Pharmacol Sin ; 41(5): 661-669, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-31932644

RESUMEN

Chronic tissue injury with fibrosis results in the disruption of tissue architecture, organ dysfunction, and eventual organ failure. Therefore, the development of effective antifibrotic drugs is urgently required. IMB-S7 is novel biphenyl compound derived from bifendate (biphenyldicarboxylate) that is used for the treatment of chronic hepatitis in China. In the current study we investigated the potential of IMB-S7 as an antihepatic fibrosis agent. In bile duct ligation (BDL) rat model, oral administration of IMB-S7 (400 mg· kg-1· d-1, for 14 days) significantly ameliorated BDL-induced liver necrosis, bile duct proliferation, and collagen accumulation. We then showed that IMB-S7 treatment markedly suppressed the TGF-ß/Smad pathway in human hepatic stellate cell line LX2 and mouse primary HSCs, as well as in liver samples of BDL rats, thus inhibiting the transcription of most fibrogenesis-associated genes, including TGF-ß1, COL1A1, and ACTA2. Furthermore, IMB-S7 treatment significantly suppressed the expression of integrin αv at the mRNA and protein levels in TGF-ß-treated LX2 cells and liver samples of BDL rats. Using integrin αv overexpression and silencing, we demonstrated that integrin αv activity correlated positively with the activation of TGF-ß/Smad pathway. Based on dual luciferase assay and DNA affinity precipitation assay, we revealed that IMB-S7 inactivated integrin αv through competitively inhibiting the binding of Sp1, a transcription factor, to the integrin αv (ITGAV) promoter (-173/-163 bp). These results suggest that IMB-S7 inhibits HSCs activation and liver fibrosis through Sp1-integrin αv signaling, and IMB-S7 may be a promising candidate to combat hepatic fibrosis in the future.


Asunto(s)
Compuestos de Bifenilo/farmacología , Integrina alfaV/genética , Cirrosis Hepática/tratamiento farmacológico , Factor de Transcripción Sp1/antagonistas & inhibidores , Animales , Conductos Biliares/cirugía , Compuestos de Bifenilo/síntesis química , Compuestos de Bifenilo/química , Células Cultivadas , Relación Dosis-Respuesta a Droga , Humanos , Integrina alfaV/metabolismo , Cirrosis Hepática/metabolismo , Cirrosis Hepática/cirugía , Estructura Molecular , Ratas , Factor de Transcripción Sp1/metabolismo , Relación Estructura-Actividad
10.
Int J Hyperthermia ; 37(1): 688-695, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32558602

RESUMEN

Objective: Hepatocellular carcinoma (HCC) is a notable threat to the longevity of elderly people. However, there is no trial to study the prognosis of these elderly patients after microwave ablation (MWA) treatment. This study investigated whether elderly patients with HCC benefit from MWA similar to younger patients.Materials and methods: Patients who underwent ultrasound-guided percutaneous MWA were included and divided into four age groups and the prognosis was compared. The senior group (Group S, ≥75 years) was then compared with the younger group (Group Y, <75 years) after a 1:1 propensity score matching was applied. The prognostic outcomes were evaluated and Cox analysis was performed to determine the factors associated with survival.Results: The four age groups showed a statistically different distribution in terms of sex, size of liver nodules, and the Charlson comorbidity index. Although Group S had a higher Charlson comorbidity index, no significant differences were found between Group S and Group Y in the rates of complete ablation and major complications as well as overall survival and progression-free survival after matching. Cox analysis demonstrated that the size of tumors and Child Pugh grade rather than age or Charlson comorbidity index were significant prognostic factors for overall survival.Conclusion: The elderly patients with HCC, even though associated with more comorbidities, may achieve acceptable prognostic outcomes following MWA, which are not worse than their younger counterparts.


Asunto(s)
Carcinoma Hepatocelular , Ablación por Catéter , Neoplasias Hepáticas , Anciano , Carcinoma Hepatocelular/diagnóstico por imagen , Carcinoma Hepatocelular/cirugía , Humanos , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/cirugía , Microondas , Pronóstico , Resultado del Tratamiento
11.
Biochem Biophys Res Commun ; 516(3): 673-679, 2019 08 27.
Artículo en Inglés | MEDLINE | ID: mdl-31248595

RESUMEN

Induced pluripotent stem cells (iPSCs) show huge variations in their differentiation potential, even in the same condition. However, methods for predicting these differentiation tendencies, especially in the early stage of differentiation, are still scarce. This study aimed to establish a simple and practical system to predict the differentiation tendency of iPSC lines using embryoid bodies (EBs) with identified parameters in the early stage. We compared four human iPSC lines in terms of the morphology and maintenance of EBs and their gene expression levels of specific markers for three germ-layers. Furthermore, the differentiation potentials of these iPSC lines into melanocytes, which are ectoderm-derived cells, were also compared and correlated with the above parameters. The results showed that iPSC lines forming regular, smooth, and not cystic EBs, which could be maintained in culture for a relatively longer time, also expressed higher levels of ectoderm-specific markers and lower levels of mesoderm/endoderm markers. Additionally, these iPSC lines showed greater potential in melanocyte differentiation using EB-based protocol, and the induced melanocytes expressed melanocytic markers and presented characteristics that were similar to those of normal human melanocytes. By contrast, iPSC lines that formed cystic EBs with bright or dark cavities and expressed relatively lower levels of ectoderm-specific markers failed in the melanocyte differentiation. Collectively, the differentiation tendency of human iPSC lines may be predicted by specific parameters in the EB stage. The formation and maintenance of optimal EBs and the expression of germ layer-specific markers are particularly important and practical for the prediction assay in the early stage.


Asunto(s)
Diferenciación Celular/genética , Cuerpos Embrioides/metabolismo , Células Madre Embrionarias/metabolismo , Células Madre Pluripotentes Inducidas/metabolismo , Melanocitos/metabolismo , Animales , Línea Celular , Células Cultivadas , Cuerpos Embrioides/citología , Células Madre Embrionarias/citología , Regulación del Desarrollo de la Expresión Génica , Estratos Germinativos/citología , Estratos Germinativos/metabolismo , Humanos , Células Madre Pluripotentes Inducidas/citología , Masculino , Melanocitos/citología , Ratones Endogámicos NOD , Ratones SCID , Proteína Homeótica Nanog/genética , Proteína Homeótica Nanog/metabolismo , Factor 3 de Transcripción de Unión a Octámeros/genética , Factor 3 de Transcripción de Unión a Octámeros/metabolismo , Factores de Transcripción SOXB1/genética , Factores de Transcripción SOXB1/metabolismo
12.
Acta Pharmacol Sin ; 40(7): 895-907, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30573812

RESUMEN

The manipulation of bile acid (BA) homeostasis by blocking the ileal apical Na+-dependent bile salt transporter (ASBT/SLC10A2) may have therapeutic effects in nonalcoholic fatty liver disease. We developed a novel ASBT inhibitor, an N-(3,4-o-dichlorophenyl)-2-(3-trifluoromethoxy) benzamide derivative referred to as IMB17-15, and investigated its therapeutic effects and the molecular mechanisms underlying the effects. Syrian golden hamsters were challenged with high-fat diet (HFD) to induce NAFLD and were subsequently administered 400 mg/kg IMB17-15 by gavage daily for 21 days. Serum, liver, and fecal samples were collected for further analysis. Plasma concentration-time profiles of IMB17-15 were also constructed. The human hepatocyte cell line HL-7702 was treated with Oleic acid (OA) with or without IMB17-15. Western blotting and real-time PCR were used to study the molecular mechanisms of IMB17-15. We found that IMB17-15 inhibited ASBT and subsequently suppressed ileal farnesoid X receptor (FXR) and FXR-activated fibroblast growth factor15/19 (FGF15/19) expression, which reduced the hepatic phosphorylated extracellular regulated protein kinase (ERK) and c-Jun N-terminal kinase (JNK) levels and upregulated the cholesterol 7α-hydroxylase (CYP7A1) activity. Additionally, IMB17-15 stimulated adenosine monophosphate (AMP)-activated protein kinase (AMPKα) phosphorylation and enhanced peroxisome proliferator activated receptor α (PPARα) expression and thus promoted triglyceride (TG) oxidation and high-density lipoprotein cholesterol (HDL-c) metabolism through an ASBT-independent mechanism. In conclusion, a novel ASBT inhibitor known as IMB17-15 protected hamsters against HFD-induced NFALD by manipulating BA and lipid homeostasis. IMB17-15 also reduced lipid deposition in human hepatic cell lines, indicating that it may be useful as a therapy for NAFLD patients.


Asunto(s)
Benzamidas/uso terapéutico , Enfermedad del Hígado Graso no Alcohólico/prevención & control , Transportadores de Anión Orgánico Sodio-Dependiente/antagonistas & inhibidores , Sulfonamidas/uso terapéutico , Simportadores/antagonistas & inhibidores , Animales , Benzamidas/farmacocinética , Benzamidas/toxicidad , Línea Celular , Citocinas/metabolismo , Dieta Alta en Grasa , Femenino , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Hígado/patología , Masculino , Mesocricetus , Ratones , Enfermedad del Hígado Graso no Alcohólico/genética , Enfermedad del Hígado Graso no Alcohólico/patología , Sulfonamidas/farmacocinética , Sulfonamidas/toxicidad
13.
Int J Syst Evol Microbiol ; 68(10): 3255-3259, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30113296

RESUMEN

An endophytic strain (designated as strain SYPF 8335T) was isolated from a root of Panax notoginseng in Wenshan district, Yunnan province of China. Strain SYPF 8335T grew very slowly and formed white colonies. Phylogenetic analysis of four loci indicated that strain SYPF 8335T was placed in the Drechmeria clade with Drechmeria campanulata as its closest phylogenetic neighbour. The nucleotide differences between strain SYPF 8335T and D. campanulata are 30 substitutions in the internal transcriber region region. A key morphological feature that differentiates the two fungi is that D. campanulata produces campanulate conidia. Combined with the morphology and molecular analyses, a new species named Drechmeria panacis sp. nov., is proposed.


Asunto(s)
Hypocreales/clasificación , Panax notoginseng/microbiología , Filogenia , Raíces de Plantas/microbiología , China , ADN de Hongos , Endófitos/clasificación , Endófitos/genética , Endófitos/aislamiento & purificación , Hypocreales/genética , Hypocreales/aislamiento & purificación , Técnicas de Tipificación Micológica , Análisis de Secuencia de ADN
14.
Int J Syst Evol Microbiol ; 68(8): 2499-2503, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29923818

RESUMEN

An endophytic strain (designated as strain SYPF 8337T) was isolated from the root of 3-year-old Panax notoginseng in Yunnan province of China. Strain SYPF 8337T grew slowly and formed pale brown to brown colonies. Phylogenetic analyses indicated that strain SYPF 8337T was placed in the Verruconis clade. Different from other Verruconis species, strain SYPF 8337T produced four-cell conidia. Furthermore, strain SYPF 8337T is the first fungus isolated as an endophyte of P. notoginseng in the genus Verruconis. Combined with the morphology and molecular analyses, a new species named Verruconis panacis sp. nov. is proposed.


Asunto(s)
Ascomicetos/clasificación , Panax notoginseng/microbiología , Filogenia , Ascomicetos/genética , Ascomicetos/aislamiento & purificación , China , ADN de Hongos/genética , Endófitos/aislamiento & purificación , Técnicas de Tipificación Micológica , Raíces de Plantas/microbiología , Análisis de Secuencia de ADN
15.
Int J Syst Evol Microbiol ; 68(8): 2468-2472, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29927367

RESUMEN

A strain (SYPF 7183T) was isolated from rhizosphere soil of Panax notoginseng in southwest China. Phylogenetic analyses indicated that strain SYPF 7183T was distinct from the other Absidia species with well-supported values. Strain SYPF 7183T produced spherical or subpyriform sporangia and short cylindrical sporangiospores. The azygospores were globose to oval. Based on morphological and phylogenetic evidence, the novel strain Absidia panacisoli sp. nov. is proposed.


Asunto(s)
Absidia/clasificación , Panax notoginseng/microbiología , Filogenia , Rizosfera , Microbiología del Suelo , Absidia/genética , Absidia/aislamiento & purificación , China , ADN de Hongos/genética , ADN Espaciador Ribosómico/genética , Técnicas de Tipificación Micológica , Análisis de Secuencia de ADN
16.
Int J Syst Evol Microbiol ; 68(5): 1509-1513, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29547095

RESUMEN

A Gram-stain-negative, strictly aerobic, yellow-coloured, motile by gliding and elongated rod-shaped bacterial strain, designated SYP-B1015T, was isolated from the rhizosphere of Artemisia annua L. Phylogenetic analyses based on 16S rRNA gene sequences indicated that strain SYP-B1015T belonged to the genus Flavobacterium and had highest 16S rRNA gene sequence similarity to Flavobacterium compostarboris JCM 16527T (98.1 %) and Flavobacterium procerum JCM 30113T (97.2 %). The predominant respiratory quinone for the strain was MK-6, and the major cellular fatty acids were iso-C15 : 0, iso-C15 : 0 3-OH and iso-C17 : 0 3-OH. The polar lipid profile contained phosphatidylethanolamine as a major compound. The DNA G+C content of strain SYP-B1015T was 33.5 mol%. The DNA-DNA relatedness values between strain SYP-B1015T and F. compostarboris JCM 16527T and F. procerum JCM 30113T were 56.5±0.4 and 48.9±1.2 %, respectively. Combining the data from morphological, physiological, biochemical and chemotaxonomic characterizations presented in this study, strain SYP-B1015T represents a novel species of the genus Flavobacterium, for which the name Flavobacterium artemisiae sp. nov. is proposed. The type strain is SYP-B1015T (=CGMCC 1.16115T=KCTC 62025T).


Asunto(s)
Artemisia annua/microbiología , Flavobacterium/clasificación , Filogenia , Rizosfera , Técnicas de Tipificación Bacteriana , Composición de Base , China , ADN Bacteriano/genética , Ácidos Grasos/química , Flavobacterium/genética , Flavobacterium/aislamiento & purificación , Fosfatidiletanolaminas/química , Pigmentación , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Vitamina K 2/análogos & derivados , Vitamina K 2/química
17.
Microb Cell Fact ; 17(1): 81, 2018 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-29778095

RESUMEN

BACKGROUND: 2-Keto-L-gulonic acid (2-KGA), the precursor of vitamin C, is currently produced by two-step fermentation. In the second step, L-sorbose is transformed into 2-KGA by the symbiosis system composed of Ketogulonicigenium vulgare and Bacillus megaterium. Due to the different nutrient requirements and the uncertain ratio of the two strains, the symbiosis system significantly limits strain improvement and fermentation optimization. RESULTS: In this study, Ketogulonicigenium robustum SPU_B003 was reported for its capability to grow well independently and to produce more 2-KGA than that of K. vulgare in a mono-culture system. The complete genome of K. robustum SPU_B003 was sequenced, and the metabolic characteristics were analyzed. Compared to the four reported K. vulgare genomes, K. robustum SPU_B003 contained more tRNAs, rRNAs, NAD and NADP biosynthetic genes, as well as regulation- and cell signaling-related genes. Moreover, the amino acid biosynthesis pathways were more complete. Two species-specific internal promoters, P1 (orf_01408 promoter) and P2 (orf_02221 promoter), were predicted and validated by detecting their initiation activity. To efficiently produce 2-KGA with decreased CO2 release, an innovative acetyl-CoA biosynthetic pathway (XFP-PTA pathway) was introduced into K. robustum SPU_B003 by expressing heterologous phosphoketolase (xfp) and phosphotransacetylase (pta) initiated by internal promoters. After gene optimization, the recombinant strain K. robustum/pBBR-P1_xfp2502-P2_pta2145 enhanced acetyl-CoA approximately 2.4-fold and increased 2-KGA production by 22.27% compared to the control strain K. robustum/pBBR1MCS-2. Accordingly, the transcriptional level of the 6-phosphogluconate dehydrogenase (pgd) and pyruvate dehydrogenase genes (pdh) decreased by 24.33 ± 6.67 and 8.67 ± 5.51%, respectively. The key genes responsible for 2-KGA biosynthesis, sorbose dehydrogenase gene (sdh) and sorbosone dehydrogenase gene (sndh), were up-regulated to different degrees in the recombinant strain. CONCLUSIONS: The genome-based functional analysis of K. robustum SPU_B003 provided a new understanding of the specific metabolic characteristics. The new XFP-PTA pathway was an efficient route to enhance acetyl-CoA levels and to therefore promote 2-KGA production.


Asunto(s)
Proteínas Bacterianas/metabolismo , Metabolismo de los Hidratos de Carbono/fisiología , Ingeniería Metabólica/métodos , Rhodobacteraceae/metabolismo , Sorbosa/metabolismo , Sorbosa/análogos & derivados
18.
Bioorg Chem ; 81: 350-355, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30193143

RESUMEN

Eighteen secondary metabolites were isolated from the fermentation broth of the endophytic fungus Xylaria sp. SYPF 8246, including four new compounds, xylarianins A-D (1-4), three new natural products, 6-methoxycarbonyl-2'-methyl-3,5,4',6'-tetramethoxy-diphenyl ether (5), 2-chlor-6-methoxycarbonyl-2'-rnethyl-3,5,4',6'-tetramethoxy-diphenyl ether (6), and 2-chlor-4'-hydroxy-6-methoxy carbonyl-2'-methyl-3,5,6'-trimethoxy-diphenyl ether (7), and eleven known compounds (8-18). Their structural elucidations were conducted by using 1D and 2D NMR, HRESIMS, and Rh2(OCOCF3)4-induced electronic circular dichroism (ECD) spectra analyses. The integrated 1H and 13C NMR data of three new natural products 5-7 were reported for the first time. All the isolated compounds were assayed for their inhibitory activities against human carboxylesterase 2 (hCE 2). Compounds 1, 5-9, and 18 displayed significant inhibitory activities against hCE 2 with IC50 values of 10.43 ±â€¯0.51, 6.69 ±â€¯0.85, 12.36 ±â€¯1.27, 18.25 ±â€¯1.78, 29.78 ±â€¯0.48, 18.86 ±â€¯1.87, and 20.72 ±â€¯1.51 µM, respectively. The interactions between compounds 1 and 5 with hCE 2 were anaylzed by molecular docking.


Asunto(s)
Benzofenonas/química , Carboxilesterasa/antagonistas & inhibidores , Succinatos/química , Xylariales/química , Benzofenonas/aislamiento & purificación , Carboxilesterasa/química , Dominio Catalítico , Humanos , Cinética , Simulación del Acoplamiento Molecular , Metabolismo Secundario , Succinatos/aislamiento & purificación , Xylariales/metabolismo
19.
Bioorg Chem ; 79: 250-256, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29775950

RESUMEN

A novel 1(2), 2(18)-diseco indole diterpenoid, drechmerin H (1), was isolated from the fermentation broth of Drechmeria sp. together with a new indole diterpenoid, 2'-epi terpendole A (3), and a known analogue, terpendole A (2). Their structures were determined by HRESIMS, 1D and 2D NMR, ECD, and X-ray single crystal diffraction analyses as well as quantum chemical calculation. The abosulte configuration of terpendole A (2) was determined for the first time. Compound 1 displayed the significant agonistic effect on pregnane X receptor (PXR) with EC50 value of 134.91 ±â€¯2.01 nM, and its interaction with PXR was investigated by molecular docking. Meantime, a plausible biosynthetic pathway for compounds 1-3 is also discussed in the present work.


Asunto(s)
Productos Biológicos/farmacología , Diterpenos/farmacología , Hypocreales/química , Indoles/farmacología , Receptor X de Pregnano/agonistas , Productos Biológicos/química , Productos Biológicos/aislamiento & purificación , Diterpenos/química , Diterpenos/aislamiento & purificación , Relación Dosis-Respuesta a Droga , Células Hep G2 , Humanos , Indoles/química , Indoles/aislamiento & purificación , Estructura Molecular , Relación Estructura-Actividad
20.
Acta Pharmacol Sin ; 39(2): 213-221, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28748913

RESUMEN

Cholestatic liver diseases are important causes of liver cirrhosis and liver transplantation, but few drugs are available for treatment. D-chiro-inositol (DCI), an isomer of inositol found in many Leguminosae plants and in animal viscera, is used clinically for the treatment of polycystic ovary syndrome (PCOS) and diabetes mellitus. In this study, we investigated whether DCI exerted an anti-cholestatic effect and its underlying mechanisms. A cholestatic rat model was established via bile duct ligation (BDL). After the surgery, the rats were given DCI (150 mg·kg-1·d-1) in drinking water for 2 weeks. Oral administration of DCI significantly decreased the serum levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST), and attenuated bile duct proliferation, parenchymal necrosis and fibrosis in BDL rats. Furthermore, DCI treatment significantly increased the serum and bile levels of total bile acid (TBA), and decreased TBA levels in the liver. Moreover, DCI treatment significantly increased expression of the genes encoding bile acid transporters BSEP (Abcb11) and MRP2 (Abcc2) in liver tissues. DCI treatment also markedly decreased hepatic CD68 and NF-kappaB (NF-κB) levels, significantly decreased the serum and hepatic MDA levels, markedly increased superoxide dismutase activity in both serum and liver tissues. Using whole-genome oligonucleotide microarray, we revealed that DCI treatment altered the expression profiles of oxidation reduction-related genes in liver tissues. Collectively, DCI effectively attenuates BDL-induced hepatic bile acid accumulation and decreases the severity of injury and fibrosis by improving bile acid secretion, repressing inflammation and decreasing oxidative stress. The results suggest that DCI might be beneficial for patients with cholestatic disorders.


Asunto(s)
Ácidos y Sales Biliares/metabolismo , Colestasis/prevención & control , Inositol/uso terapéutico , Estrés Oxidativo/efectos de los fármacos , Sustancias Protectoras/uso terapéutico , Miembro 11 de la Subfamilia B de Transportador de Casetes de Unión al ATP/genética , Miembro 11 de la Subfamilia B de Transportador de Casetes de Unión al ATP/metabolismo , Transportadoras de Casetes de Unión a ATP/genética , Transportadoras de Casetes de Unión a ATP/metabolismo , Alanina Transaminasa/sangre , Animales , Antígenos CD/metabolismo , Antígenos de Diferenciación Mielomonocítica/metabolismo , Aspartato Aminotransferasas/sangre , Conductos Biliares/cirugía , Modelos Animales de Enfermedad , Expresión Génica/efectos de los fármacos , Inositol/administración & dosificación , Ligadura , Hígado/patología , Cirrosis Hepática/prevención & control , Masculino , FN-kappa B/metabolismo , Sustancias Protectoras/administración & dosificación , Ratas Sprague-Dawley , Estereoisomerismo , Superóxido Dismutasa/metabolismo
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