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1.
Mol Biol Rep ; 51(1): 774, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38904794

RESUMEN

BACKGROUND: Olive is an evergreen tree of Oleaceae Olea with numerous bioactive components. While the anti-inflammatory properties of olive oil and the derivatives are well-documented, there remains a dearth of in-depth researches on the immunosuppressive effects of olive fruit water extract. This study aimed to elucidate the dose-effect relationship and underlying molecular mechanisms of olive fruit extract in mediating anti-inflammatory responses. METHODS AND RESULTS: The impacts of olive fruit extract on the release of nitric oxide (NO), tumor necrosis factor (TNF-α), interleukins-6 (IL-6) and reactive oxygen species (ROS) were assessed in RAW264.7 cells induced by lipopolysaccharide (LPS). For deeper understanding, the expression of genes encoding inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), TNF-α and IL-6 was quantitatively tested. Additionally, the expression patterns of MAPK and NF-κB pathways were further observed to analyze the action mechanisms. Results suggested that olive fruit extract (200, 500, 1000 µg/mL) markedly exhibited a dose-dependent reduction in the generation of NO, TNF-α, IL-6 and ROS, as well as the expression of correlative genes studied. The activation of ERK, JNK, p38, IκB-α and p65 were all suppressed when p65 nuclear translocation was further restricted by olive fruit extract in NF-κB and MAPK signal pathways. CONCLUSIONS: Olive fruit extract targeted imposing restrictions on the signal transduction of key proteins in NF-κB and MAPK pathways, and thereby lowered the level of inflammatory mediators, which put an enormous hindrance to inflammatory development. Accordingly, it is reasonable to consider olive fruit as a potent ingredient in immunomodulatory products.


Asunto(s)
Antiinflamatorios , Frutas , Lipopolisacáridos , FN-kappa B , Óxido Nítrico , Olea , Extractos Vegetales , Especies Reactivas de Oxígeno , Transducción de Señal , Animales , Olea/química , Ratones , Células RAW 264.7 , Extractos Vegetales/farmacología , Antiinflamatorios/farmacología , Lipopolisacáridos/farmacología , FN-kappa B/metabolismo , Frutas/química , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal/efectos de los fármacos , Óxido Nítrico/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Interleucina-6/metabolismo , Interleucina-6/genética , Óxido Nítrico Sintasa de Tipo II/metabolismo , Óxido Nítrico Sintasa de Tipo II/genética , Ciclooxigenasa 2/metabolismo , Ciclooxigenasa 2/genética , Supervivencia Celular/efectos de los fármacos , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo
2.
Anal Bioanal Chem ; 2024 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-38704473

RESUMEN

Nanoceria have demonstrated a wide array of catalytic activity similar to natural enzymes, holding considerable significance in the colorimetric detection of alkaline phosphatase (ALP), which is a biomarker of various biological disorders. However, the issues of physiological stability and formation of protein corona, which are strongly related to their surface chemistry, limit their practical application. In this work, CeO2 nanoparticles characterized by enhanced dimensional uniformity and specific surface area were synthesized, followed by encapsulation with various polymers to further increase catalytic activity and physiological stability. Notably, the CeO2 nanoparticles encapsulated within each polymer exhibited improved catalytic characteristics, with PAA-capped CeO2 exhibiting the highest performance. We further demonstrated that the PAA-CeO2 obtained with enhanced catalytic activity was attributed to an increase in surface negative charge. PAA-CeO2 enabled the quantitative assessment of AA activity within a wide concentration range of 10 to 60 µM, with a detection limit of 0.111 µM. Similarly, it allowed for the evaluation of alkaline phosphatase activity throughout a broad range of 10 to 80 U/L, with a detection limit of 0.12 U/L. These detection limits provided adequate sensitivity for the practical detection of ALP in human serum.

3.
Ann Hematol ; 102(9): 2435-2444, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37162517

RESUMEN

PD-L1+ exosome have been reported to be a promising prognostic biomarker in various cancers. However, its clinical value in diffuse large B cell lymphoma (DLBCL) has not been defined yet. In this study, a total of 165 plasma samples from 78 patients with DLBCL undergoing standard first-line R-CHOP regimens were collected at three different time points (pretreatment, and after 3 and 6 cycles of R-CHOP) to determine the proportions of PD-L1+ exosomes by flow cytometry. We found that high pretreatment plasma PD-L1+ exosome correlated with indicators of poor clinical outcome that included high Ki-67 expression (P = 0.02), double expressor lymphoma (P = 0.005), immunohistochemical PD-L1+ tumor tissue (P = 0.006), and the baseline maximal standardized uptake values (P = 0.0003). Pretreatment plasma PD-L1+ exosome was an independent factor by multivariate analysis with logistic regression (P = 0.0301). Moreover, the pretreatment PD-L1+ exosome was a strong predictor of final treatment responses of either CR or non-CR by ROC analysis (P < 0.001). PD-L1+ exosome level declined significantly in patients who experienced CR (pretreatment vs. after 3 cycles/after 6 cycles, P < 0.05), but not in the non-CR group. Intriguingly, plasma PD-L1+ exosome after 3 cycles (AUC = 0.857; 95%CI: 0.728-0.939) might represent a more sensitive indicator than radiographic assessment after 3 cycles (AUC = 0.626; 95%CI: 0.477-0.758) for evaluating the therapeutic response of DLBCL patients (P = 0.0136). Our results suggest that plasma PD-L1+ exosomes may represent a new biomarker for the dynamic monitoring of treatment response.


Asunto(s)
Antígeno B7-H1 , Exosomas , Linfoma de Células B Grandes Difuso , Humanos , Biomarcadores de Tumor/metabolismo , Relevancia Clínica , Exosomas/metabolismo , Exosomas/patología , Linfoma de Células B Grandes Difuso/tratamiento farmacológico , Linfoma de Células B Grandes Difuso/metabolismo , Pronóstico
4.
Biomacromolecules ; 24(11): 5381-5393, 2023 11 13.
Artículo en Inglés | MEDLINE | ID: mdl-37908117

RESUMEN

A major challenge to make use of lignin as an antimicrobial material is the weak antimicrobial activity of industrial lignin. Inspired by the antimicrobial mechanism of actions of antimicrobial peptides, alkyldiamines were employed as lysine mimics for lignin modifications. Accordingly, aminoalkyl-modified lignins with different degrees of substitution of amino groups and different hydrophobicity were synthesized. The chemical structure, properties, and antimicrobial activities of the as-prepared aminoalkyl lignins were thoroughly characterized with state-of-the-art technologies. The results indicated that aminobutyl lignin showed enhanced antimicrobial activity against S. aureus and E. coli and performed even better than copper ions. The antimicrobial mechanism of action of the as-prepared aminobutyl lignin was similar to that of polylysine, which damaged the cell membrane, leading to the leakage of intracellular molecules and death of the cell. This study provides a feasible approach to afford modified lignin with enhanced antimicrobial performance, which would facilitate the high-value valorization of lignin as biological materials.


Asunto(s)
Péptidos Antimicrobianos , Lignina , Lignina/farmacología , Lignina/química , Escherichia coli , Staphylococcus aureus
5.
Antonie Van Leeuwenhoek ; 116(11): 1185-1195, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37704902

RESUMEN

A Gram-positive, facultatively anaerobic, oval beaded-shape, oxidase-negative, and non-motile bacterium designated DM20194951T was isolated from a spoiled eye mask obtained from Guangdong, China. Based on the 16S rRNA gene sequence, phylogenetic analysis indicated that strain DM20194951T showed the highest sequence similarity (95.8%) to Fundicoccus ignavus WS4937T. Meanwhile, strain DM20194951T could be distinguished from the type strains in the genus Fundicoccus by distinct phenotypic and genotypic traits. Strain DM20194951T grew variably with 1-2% (w/v) NaCl and tolerated pH 6.0-10.0. Growth was observed from 28 to 37 °C. The diagnostic diamino acids in the cell-wall peptidoglycan consisted of aspartic and glutamic acids as well as alanine. The predominant fatty acids were C18:1 ω9c, C16:0, and C16:1 ω9c. In the polar lipid profile, two glycolipids, three phospholipids, one phosphatidylglycerol, and one diphosphatidylglycerol were found. No respiratory quinones were detected. The DM20194951T genome is 3.2 Mb in size and contains a G + C content of 38.1%. A gene cluster for lactococcin 972 family bacteriocin production was found in the DM20194951T genome. Based on morphological, genotypic, and phylogenetic data, strain DM20194951T should be considered to represent a novel species in the genus Fundicoccus, for which the name Fundicoccus culcitae sp. nov. is proposed with the type strain DM20194951T (= KCTC 43472T = GDMCC 1.3614T).

6.
J Nanobiotechnology ; 20(1): 492, 2022 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-36424663

RESUMEN

BACKGROUND: Pathogenic microorganism pollution has been a challenging public safety issue, attracting considerable scientific interest. A more problematic aspect of this phenomenon is that planktonic bacteria exacerbate biofilm formation. There is an overwhelming demand for developing ultra-efficient, anti-drug resistance, and biocompatibility alternatives to eliminate stubborn pathogenic strains and biofilms. RESULTS: The present work aims to construct a visible light-induced anti-pathogen agents to ablate biofilms using the complementary merits of ROS and cationic polymers. The photosensitizer chlorin e6-loaded polyethyleneimine-based micelle (Ce6-TPP-PEI) was constructed by an amphiphilic dendritic polymer (TPP-PEI) and physically loaded with photosensitizer chlorin e6. Cationic polymers can promote the interaction between photosensitizer and Gram-negative bacteria, resulting in enhanced targeting of PS and lethality of photodynamic therapy, and remain active for a longer duration to prevent bacterial re-growth when the light is turned off. As expected, an eminent antibacterial effect was observed on the Gram-negative Escherichia coli, which is usually insensitive to photosensitizers. Surprisingly, the cationic polymer and photodynamic combination also exert significant inhibitory and ablative effects on fungi and biofilms. Subsequently, cell hemolysis assessments suggested its good biocompatibility. CONCLUSIONS: Given the above results, the platform developed in this work is an efficient and safe tool for public healthcare and environmental remediation.


Asunto(s)
Fotoquimioterapia , Fármacos Fotosensibilizantes , Fármacos Fotosensibilizantes/farmacología , Polímeros/farmacología , Fotoquimioterapia/métodos , Biopelículas , Luz , Cationes/farmacología
7.
World J Microbiol Biotechnol ; 39(1): 15, 2022 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-36401137

RESUMEN

Bacterial outer membrane proteins (Omps) are essential for environmental sensing, stress responses, and substance transport. Our previous study discovered that OmpA contributes to planktonic growth, biocide resistance, biofilm formation, and swimming motility in Citrobacter werkmanii, whereas the molecular functions of OmpF in this strain are largely unknown. Thus, in this study, the ompF gene was firstly knocked out from the genome of C. werkmanii using a homologous recombination method, and its phenotypical alternations of ∆ompF were then thoroughly characterized using biochemical and molecular approaches with the parental wild type (WT) and complementary (∆ompF-com) strains. The results demonstrated that the swimming ability of ∆ompF on semi-solid plates was reduced compared to WT due to the down-regulation of flgC, flgH, fliK, and fliF. Meanwhile, ompF deletion reduces biofilm formation on both glass and polystyrene surfaces due to decreased cell aggregation. Furthermore, ompF inactivation induced different osmotic stress (carbon sources and metal ions) responses in its biofilms when compared to WT and ∆ompF-com. Finally, a total of 6 maltose metabolic genes of lamB, malE, malK, malG, malM, and malF were all up-regulated in ∆ompF. The gene knockout and HPLC results revealed that the MalEFGK2 cluster was primarily responsible for maltose transport in C. werkmanii. Furthermore, we discovered for the first time that the upstream promoter of OmpF and its transcription can be combined with and negatively regulated by MalT. Overall, OmpF plays a role in a variety of biochemical processes and molecular functions in C. werkmanii, and it may even act as a targeted site to inhibit biofilm formation.


Asunto(s)
Maltosa , Natación , Osmorregulación , Proteínas de la Membrana Bacteriana Externa/genética , Biopelículas
8.
Bioorg Chem ; 115: 105270, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34467939

RESUMEN

A series of 1,2,4-triazole-norfloxacin hybrids was designed, synthesized, and evaluated for in vitro antibacterial activity against common pathogens. All the newly synthesized compounds were characterized by Fourier-transform infrared spectrophotometry, proton and carbon nuclear magnetic resonance, and electrospray ionization-mass spectrometry. Representative compounds from each step of the synthesis were further characterized by X-ray crystallography. Many of the compounds synthesized exhibited antibacterial activity superior to that of norfloxacin toward both, gram-positive and gram-negative bacteria. The toxicity of the 1,2,4-triazole-norfloxacin hybrids toward bacterial cells was 32-512 times higher than that toward mouse fibroblast cells. Moreover, hemolysis was not observed at concentrations of 64 µg/mL, suggesting good biocompatibility. Molecular docking showed a least binding energy of -9.4 to -9.7 kcal/mol, and all compounds were predicted to show remarkable affinity for the bacterial topoisomerase IV.


Asunto(s)
Antibacterianos/farmacología , Relación Dosis-Respuesta a Droga , Simulación del Acoplamiento Molecular , Norfloxacino/farmacología , Triazoles/farmacología , Antibacterianos/síntesis química , Antibacterianos/química , Cristalografía por Rayos X , Escherichia coli/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Norfloxacino/síntesis química , Norfloxacino/química , Pseudomonas aeruginosa/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , Relación Estructura-Actividad , Triazoles/síntesis química , Triazoles/química
9.
Appl Microbiol Biotechnol ; 105(7): 2841-2854, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33763710

RESUMEN

The genus Citrobacter is commonly found in environmental and industrial settings, some members of which have been used for bioremediation of heavy metals owing to the absorption ability of their biofilms. Although our previous studies have found that the outer membrane protein A (OmpA) contributes to the process of Citrobacter werkmanii biofilm formation, the underlying mechanisms remain elusive. Therefore, we deleted ompA from the genome of C. werkmanii and investigated its phenotypes in comparison to the wild type strain (WT) and the complementary strain using biochemical and molecular techniques including RNA-Seq. Our results demonstrated that the deletion of ompA led to an increase in biofilm formation on both polystyrene and glass surfaces due to upregulation of some biofilm formation related genes. Meanwhile, swimming ability, which is mediated by activation of flagellar assembly genes, was increased on semi-solid plates in the ∆ompA strain when compared with WT. Additionally, inactivation of ompA also caused increased 1,2-benzisothiazolin-3-one (BIT) resistance, differential responses to Ca2+ stress, curli protein expression and cellulose production. Finally, ∆ompA caused differential expression of a total of 1470 genes when compared with WT, of which 146 were upregulated and 1324 were downregulated. These genes were classified into different Gene Ontology (GO) and KEGG pathways. In summary, ompA in C. werkmanii contributes to a variety of biological functions and may act as a target site to modulate biofilm formation. KEY POINTS: • ompA is a negative regulator for biofilm formation by C. werkmanii. • ompA inhibits swimming motility of C. werkmanii. • ompA deletion causes different expression profiles in C. werkmanii.


Asunto(s)
Desinfectantes , Proteínas Bacterianas/genética , Biopelículas , Citrobacter/genética , Regulación Bacteriana de la Expresión Génica , Natación
10.
Int J Mol Sci ; 22(18)2021 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-34575861

RESUMEN

Heavy metal pollution is widespread and persistent, and causes serious harm to the environment. Pseudomonas putida, a representative environmental microorganism, has strong resistance to heavy metals due to its multiple efflux systems. Although the functions of many efflux systems have been well-studied, the relationship between them remains unclear. Here, the relationship between the Czc and Cad systems that are predominantly responsible for cadmium efflux in P. putida KT2440 is identified. The results demonstrated that CzcR3, the response regulator of two-component system CzcRS3 in the Czc system, activates the expression of efflux pump genes czcCBA1 and czcCBA2 by directly binding to their promoters, thereby helping the strain resist cadmium stress. CzcR3 can also bind to its own promoter, but it has only a weak regulatory effect. The high-level expression of czcRS3 needs to be induced by Cd2+, and this relies on the regulation of CadR, a key regulator in the Cad system, which showed affinity to czcRS3 promoter. Our study indicates that the Cad system is involved in the regulation of the Czc system, and this relationship is important for maintaining the considerable resistance to cadmium in P. putida.


Asunto(s)
Cadmio/química , Farmacorresistencia Fúngica , Regulación Fúngica de la Expresión Génica , Pseudomonas putida/efectos de los fármacos , Proteínas Bacterianas/metabolismo , Citoplasma/metabolismo , Desoxirribonucleasa I/metabolismo , Colorantes Fluorescentes/farmacología , Regulación Bacteriana de la Expresión Génica/efectos de los fármacos , Genes Bacterianos , Plomo/química , Metales , Metales Pesados/metabolismo , Regiones Promotoras Genéticas/efectos de los fármacos , Unión Proteica , Especificidad de la Especie , Zinc/química , beta-Galactosidasa/metabolismo
11.
Mol Ther ; 27(3): 542-558, 2019 03 06.
Artículo en Inglés | MEDLINE | ID: mdl-30799283

RESUMEN

Erbin has been shown to have significant effects on the development of solid tumors. However, little is known about its function and regulatory mechanism in hematological malignancies. The biological function of Erbin on cell proliferation was measured in vitro and in vivo. The predicted target of Erbin was validated by dual-luciferase reporter assay and rescue experiment. We found that overexpression of Erbin could inhibit the cell proliferation and promote the cell differentiation of acute myeloid leukemia (AML) cells, whereas depletion of Erbin could enhance the cell proliferation and block the cell differentiation in AML cells in vitro and in vivo. Besides, miR-183-5p was identified as the upstream regulator that negatively regulated the Erbin expression. The results were confirmed by dual-luciferase reporter and RNA pull-down assay. Furthermore, we found that miR-183-5p negatively regulated Erbin, resulting in enhanced cell proliferation of AML cells via activation of RAS/RAF/MEK/ERK and PI3K/AKT/FoxO3a pathways. The activation of RAS/RAF/MEK/ERK and PI3K/AKT/FoxO3a pathways was mediated by Erbin interacting with Grb2. These results were also validated by rescue experiments in vitro and in vivo. All above-mentioned findings indicated that the miR-183-5p/Erbin signaling pathway might represent a novel prognostic biomarker or therapeutic target for treatment of AML.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , Diferenciación Celular/fisiología , Proteína Forkhead Box O3/metabolismo , Leucemia Mieloide/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Diferenciación Celular/genética , Proliferación Celular/genética , Proliferación Celular/fisiología , Citometría de Flujo , Proteína Forkhead Box O3/genética , Células HL-60 , Humanos , Leucemia Mieloide/genética , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Fosfatidilinositol 3-Quinasas/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Transducción de Señal/genética , Transducción de Señal/fisiología , Células U937
12.
J Cosmet Sci ; 71(3): 133-148, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33022209

RESUMEN

Many outbreaks of Burkholderia cepacia complex (Bcc) infections are associated with contaminations in personal care products (PCPs). This study aimed to analyze a collection of Bcc isolates in PCPs and assess the susceptibility of preservatives, including dimethoxy dimethyl hydantoin (DMDMH), methylisothiazolinone-chloromethylisothiazolinone (MIT/cMIT), and methyl 4-hydroxybenzoate (MH). The Bcc isolates collected during the 3-year (2015-2017) study period were further examined by biochemical identification system, phylogenetic analysis based on recA nucleotide sequences, and multilocus sequence typing analysis. Preservatives susceptibility testing of Bcc bacteria were evaluated by minimum inhibitory concentration and minimum bactericidal concentration. A total of seven distinct sequence types (STs) were identified, which belonged to four different Bcc species: Burkholderia cenocepacia (ST621, ST258, and novel ST), Burkholderia lata (ST339 and ST336), Burkholderia contaminans (ST482), Burkholderia cepacia (ST922). For DMDMH and MH, the maximum permitted concentrations according to the safety specification of cosmetics (0.6% and 0.4%) were able to inhibit or kill all Bcc strains, but 40% of Bcc isolates could survive at higher than maximum permitted concentrations of MIT/cMIT (of a mixture in the ratio 3:1 of 5-chloro-2-methyl-4-isothiazolin-3-one and 2-methyl-4-isothiazolin-3-one). The PCPs contamination of Bcc strains should be given more attention by manufacturers because of its diversity in molecular epidemiology and its low susceptibility to preservatives such as MIT/cMIT.


Asunto(s)
Complejo Burkholderia cepacia , Cosméticos , Técnicas de Tipificación Bacteriana , Burkholderia , Complejo Burkholderia cepacia/genética , Cosméticos/efectos adversos , Epidemiología Molecular , Filogenia
13.
Acta Haematol ; 142(2): 98-104, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31085908

RESUMEN

The diagnostic hallmark of acute promyelocytic leukemia (APL) is the reciprocal translocation t(15;17), resulting in the characteristic PML-RARA fusion; however, patients occasionally have masked PML-RARArearrangements. We report an APL case with no evidence of t(15;17) or PML-RARA rearrangement by karyotype or commercial reverse transcription polymerase chain reaction analyses. Fluorescence in situ hybridization detected a small RARA insertion signal within PML. mRNA sequencing identified a novel PML-RARA transcript generated from the juxtaposition of PMLIIa (exons 1-4, 6, and 7ab) and RARA exons (3-9), with novel breakpoints in PML exon 7b and RARA exon 3. The patient achieved molecular remission after the second consolidation chemotherapy and remains in complete remission 22 months after initial presentation. This is the first report of an APL case presenting with submicroscopic ins(15;17) and simultaneous novel breakpoints in both PML and RARA. This case highlights the importance of sequence analysis to confirm APL diagnosis and for subsequent monitoring of minimal residual disease.


Asunto(s)
Exones , Sitios Genéticos , Leucemia Promielocítica Aguda/genética , Mutagénesis Insercional , Proteínas de Fusión Oncogénica/genética , Adulto , Humanos , Hibridación Fluorescente in Situ , Leucemia Promielocítica Aguda/diagnóstico , Leucemia Promielocítica Aguda/tratamiento farmacológico , Leucemia Promielocítica Aguda/patología , Masculino
14.
J Ind Microbiol Biotechnol ; 46(12): 1757-1768, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31512096

RESUMEN

Through our previous study, we found an up-regulation in the expression of nitrite reductase (nirS) in the isothiazolone-resistant strain of Pseudomonas aeruginosa. However, the definitive molecular role of nirS in ascribing the resistance remained elusive. In the present study, the nirS gene was deleted from the chromosome of P. aeruginosa ATCC 9027 and the resulting phenotypic changes of ΔnirS were studied alongside the wild-type (WT) strain under aerobic conditions. The results demonstrated a decline in the formations of biofilms but not planktonic growth by ΔnirS as compared to WT, especially in the presence of benzisothiazolinone (BIT). Meanwhile, the deletion of nirS impaired swimming motility of P. aeruginosa under the stress of BIT. To assess the influence of nirS on the transcriptome of P. aeruginosa, RNA-seq experiments comparing the ΔnirS with WT were also performed. A total of 694 genes were found to be differentially expressed in ΔnirS, of which 192 were up-regulated, while 502 were down-regulated. In addition, these differently expressed genes were noted to significantly enrich the carbon metabolism along with glyoxylate and dicarboxylate metabolisms. Meanwhile, results from RT-PCR suggested the contribution of mexEF-oprN to the development of BIT resistance by ΔnirS. Further, c-di-GMP was less in ΔnirS than in WT, as revealed by HPLC. Taken together, our results confirm that nirS of P. aeruginosa ATCC 9027 plays a role in BIT resistance along with biofilm formation and further affects several metabolic patterns under aerobic conditions.


Asunto(s)
Nitrito Reductasas/metabolismo , Pseudomonas aeruginosa/enzimología , Aerobiosis , Biopelículas , Regulación Bacteriana de la Expresión Génica , Nitrito Reductasas/genética , Pseudomonas aeruginosa/genética , Transcriptoma
15.
J Basic Microbiol ; 59(11): 1154-1162, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31553498

RESUMEN

Nitric oxide (NO) reductase (NorCB) of Pseudomonas aeruginosa is an essential enzyme that metabolizes NO and alleviates anaerobic NO toxicity during denitrification processes under anaerobic conditions. However, the molecular functions of norCB in the presence of oxygen are poorly understood. This study utilized norCB knockout from P. aeruginosa ATCC 9027 to analyze the resulting phenotypic changes of ΔnorCB in comparison to the wild-type parental strain (WT) and the complementary strain (ΔnorCB-com). The results demonstrated an increase in planktonic growth and biofilm formation by ΔnorCB compared to WT and ΔnorCB-com in the presence of isothiazolones under aerobic conditions. Deletion of norCB led to increased swimming ability and decreased pyocyanin production. Inactivation of norCB also led to an increase of cellular H2 O2 concentration due to decreased activity of its catalases. In addition, the deletion of norCB also influenced the relative expressions of several other genes, including norD, nirS, hmgA, and hpd. These findings provide preliminary evidence that norCB in P. aeruginosa plays an essential role in bacterial life process under aerobic conditions and improves the application of denitrification in the next step.


Asunto(s)
Proteínas Bacterianas/metabolismo , Oxidorreductasas/metabolismo , Pseudomonas aeruginosa/metabolismo , Aerobiosis , Proteínas Bacterianas/genética , Biopelículas/crecimiento & desarrollo , Regulación Bacteriana de la Expresión Génica , Técnicas de Inactivación de Genes , Peróxido de Hidrógeno/metabolismo , Locomoción/genética , Oxidorreductasas/genética , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/crecimiento & desarrollo , Piocianina/biosíntesis
16.
Appl Microbiol Biotechnol ; 102(17): 7555-7564, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29951860

RESUMEN

Garlic oil can disrupt the quorum sensing (QS) pathways of the opportunistic pathogen Pseudomonas aeruginosa; however, the underlying mechanisms for this effect are unclear. Diallyl disulfide (DADS) is one of the most abundant sulfur-containing compounds in garlic oil. This study investigated the effects of DADS on the growth, virulence factor production (elastase, pyocyanin, biofilm, and swarming motility), and essential gene expression of P. aeruginosa PAO1, particularly as they apply to QS and virulence. DADS at 1.28 mg/mL did not affect P. aeruginosa PAO1 growth, although it decreased elastase and pyocyanin production, biofilm formation, and swarming motility. Each of these phenomena is regulated by the three QS systems of P. aeruginosa PAO1 (las, rhl, and pqs). Real-time q-PCR revealed that DADS down-regulated the transcription levels of several important QS genes (lasI, lasR, rhlI, rhlR, pqsA, and pqsR) in the three systems. Furthermore, the transcription levels of QS-regulated virulence genes were also down-regulated. The lasB gene, encoding LasB elastase, is co-regulated by the las, rhl, and pqs systems, and thus the down-regulation of genes across the three systems further down-regulated lasB. Additionally, phzM (encoding pyocyanin), pslB (responsible for the production of a biofilm matrix polysaccharide), and chiC (encoding chitinase) were positively activated by LasR, and a decrease in lasR transcription further down-regulated the transcription of phzM, pslB, and chiC. Hence, DADS inhibits P. aeruginosa PAO1 virulence factors by inactivating the transcription of key genes across three different QS systems.


Asunto(s)
Compuestos Alílicos/química , Compuestos Alílicos/farmacología , Proteínas Bacterianas/genética , Disulfuros/farmacología , Regulación Bacteriana de la Expresión Génica/efectos de los fármacos , Pseudomonas aeruginosa/efectos de los fármacos , Percepción de Quorum/genética , Sulfuros/química , Factores de Virulencia/genética , Antibacterianos/farmacología , Biopelículas
17.
Int J Mol Sci ; 19(9)2018 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-30200616

RESUMEN

To screen, identify and study the genes involved in isothiazolone resistance and biofilm formation in Citrobacter werkmanii strain BF-6. A Tn5 transposon library of approximately 900 mutants of C. werkmanii strain BF-6 was generated and screened to isolate 1,2-benzisothiazolin-3-one (BIT) resistant strains. In addition, the tRNA 2-thiocytidine (32) synthetase gene (ttcA) was deleted through homologous recombination and the resulting phenotypic changes of the ΔttcA mutant were studied. A total of 3 genes were successfully identified, among which ΔttcA mutant exhibited a reduction in growth rate and swimming motility. On the other hand, an increase in biofilms formation in ΔttcA were observed but not with a significant resistance enhancement to BIT. This work, for the first time, highlights the role of ttcA gene of C. werkmanii strain BF-6 in BIT resistance and biofilm formation.


Asunto(s)
Biopelículas/crecimiento & desarrollo , Citrobacter/fisiología , Desinfectantes/farmacología , Sulfurtransferasas/genética , Proteínas Bacterianas/genética , Biopelículas/efectos de los fármacos , Citrobacter/efectos de los fármacos , Farmacorresistencia Bacteriana , Biblioteca de Genes , Mutagénesis , Filogenia , Tiazoles/farmacología
18.
BMC Genomics ; 18(1): 765, 2017 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-29017450

RESUMEN

BACKGROUND: In our previous study, Citrobacter werkmanii BF-6 was isolated from an industrial spoilage sample and demonstrated an excellent ability to form biofilms, which could be affected by various environmental factors. However, the genome sequence of this organism has not been reported so far. RESULTS: We report the complete genome sequence of C. werkmanii BF-6 together with the description of the genome features and its annotation. The size of the complete chromosome is 4,929,789 bp with an average coverage of 137×. The chromosome exhibits an average G + C content of 52.0%, and encodes 4570 protein coding genes, 84 tRNA genes, 25 rRNA operons, 3 microsatellite sequences and 34 minisatellite sequences. A previously unknown circular plasmid designated as pCW001 was also found with a length of 212,549 bp and a G + C content of 48.2%. 73.5%, 75.6% and 92.6% of the protein coding genes could be assigned to GO Ontology, KEGG Pathway, and COG (Clusters of Orthologous Groups) categories respectively. C. werkmanii BF-6 and C. werkmanii NRBC 105721 exhibited the closest evolutionary relationships based on 16S ribosomal RNA and core-pan genome assay. Furthermore, C. werkmanii BF-6 exhibits typical bacterial biofilm formation and development. In the RT-PCR experiments, we found that a great number of biofilm related genes, such as bsmA, bssR, bssS, hmsP, tabA, csgA, csgB, csgC, csgD, csgE, and csgG, were involved in C. werkmanii BF-6 biofilm formation. CONCLUSIONS: This is the first complete genome of C. werkmanii. Our work highlights the potential genetic mechanisms involved in biofilm formation and paves a way for further application of C. werkmanii in biofilms research.


Asunto(s)
Citrobacter/genética , Genómica , Industrias , Biopelículas , Citrobacter/fisiología , Genoma Bacteriano/genética
19.
Cell Physiol Biochem ; 39(5): 1891-1904, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27771712

RESUMEN

INTRODUCTION: This pooled analysis study aimed to reveal the prognostic relevance of microRNAs (miRNAs) in patients with diffuse large B-cell lymphoma (DLBCL). MATERIALS AND METHODS: We examined the impact of miRNAs on clinical outcome. Eligible studies were identified and quality assessed using multiple search strategies. Data were extracted from included studies which correlated survival with expression of miRNAs (serum or tissue). RESULTS: We pooled proper studies, and combined the hazard ratios with 95% confidence intervals to estimate strength of the correlations. There were 18 studies including 1950 patients with DLBCL eligible for pooled analysis. We found significant combined HRs for poor overall survival for high expression of miR-21 and low expression of miR-224 in tumor tissue, but for favorable relapse free survival for high expression of miR-21 in serum. Progression free survival was shortened in patients with low expression of miR-199a/b, miR-146b-5p, miR-224 and high expression of miR-222. CONCLUSION: MiRNAs may act as independent prognostic factors in patients with DLBCL, and useful in risk stratification.


Asunto(s)
Regulación Neoplásica de la Expresión Génica , Linfoma de Células B Grandes Difuso/diagnóstico , Linfoma de Células B Grandes Difuso/genética , MicroARNs/genética , Supervivencia sin Enfermedad , Humanos , Linfoma de Células B Grandes Difuso/mortalidad , Linfoma de Células B Grandes Difuso/patología , Pronóstico , Modelos de Riesgos Proporcionales , Transducción de Señal
20.
Ann Hematol ; 95(7): 1051-7, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27116384

RESUMEN

In our previous in vitro trials, decitabine and all-trans retinoic acid (ATRA) demonstrated synergistic effects on growth inhibition, differentiation, and apoptosis in SHI-1 cells; in K562 cells, ATRA enhanced the effect of decitabine on p16 demethylation, and the combination of the two drugs was found to activate RAR-ß expression (p16 and RAR-ß are two tumor suppressor genes). On the rationale of our in vitro trials, we used low-dose decitabine and ATRA to treat 31 myeloid neoplasms deemed ineligible for intensive chemotherapy. The regimen consisted of decitabine at the dose of 15 mg/m(2) intravenously over 1 h daily for consecutive 5 days and ATRA at the dose of 20 mg/m(2) orally from day 1 to 28 except day 4 to 28 in the first cycle, and the regimen was repeated every 28 days. After 6 cycles, decitabine treatment was stopped, and ATRA treatment was continued for maintenance treatment. Treated with a median of 2 cycles (range 1-6), 7 patients (22.6 %) achieved complete remission (CR), 7 (22.6 %) marrow CR (mCR), and 4 (12.9 %) partial remission (PR). The overall remission (CR, mCR, and PR) rate was 58.1 %, and the best response (CR and mCR) rate was 45.2 %. The median overall survival (OS) was 11.0 months, the 1-year OS rate was 41.9 %, and the 2-year OS rate was 26.6 %. In univariate analyses, age, performance status, comorbidities, white blood cell counts and platelets at diagnosis, percentage of bone marrow blasts, karyotype, and treatment efficacy demonstrated no impacts on OS (P > 0.05, each). Main side effects were tolerable hematologic toxicities. In conclusion, low-dose decitabine plus ATRA is a promising treatment for patients with myeloid neoplasms judged ineligible for intensive chemotherapy.


Asunto(s)
Antimetabolitos Antineoplásicos/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Azacitidina/análogos & derivados , Leucemia Mieloide Aguda/tratamiento farmacológico , Síndromes Mielodisplásicos/tratamiento farmacológico , Tretinoina/administración & dosificación , Adulto , Anciano , Anciano de 80 o más Años , Azacitidina/administración & dosificación , Decitabina , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Leucemia Mieloide Aguda/diagnóstico , Masculino , Persona de Mediana Edad , Síndromes Mielodisplásicos/diagnóstico
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