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1.
Proc Natl Acad Sci U S A ; 120(4): e2209528120, 2023 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-36649428

RESUMO

Sepsis is a lethal syndrome manifested by an unregulated, overwhelming inflammation from the host in response to infection. Here, we exploit the use of a synthetic heparan sulfate octadecasaccharide (18-mer) to protect against sepsis. The 18-mer not only inhibits the pro-inflammatory activity of extracellular histone H3 and high mobility group box 1 (HMGB1), but also elicits the anti-inflammatory effect from apolipoprotein A-I (ApoA-I). We demonstrate that the 18-mer protects against sepsis-related injury and improves survival in cecal ligation and puncture mice and reduces inflammation in an endotoxemia mouse model. The 18-mer neutralizes the cytotoxic histone-3 (H3) through direct interaction with the protein. Furthermore, the 18-mer enlists the actions of ApoA-I to dissociate the complex of HMGB1 and lipopolysaccharide, a toxic complex contributing to cell death and tissue damage in sepsis. Our study provides strong evidence that the 18-mer mitigates inflammatory damage in sepsis by targeting numerous mediators, setting it apart from other potential therapies with a single target.


Assuntos
Endotoxemia , Proteína HMGB1 , Sepse , Camundongos , Animais , Proteína HMGB1/metabolismo , Apolipoproteína A-I , Sepse/tratamento farmacológico , Sepse/metabolismo , Lipopolissacarídeos , Heparitina Sulfato , Modelos Animais de Doenças
2.
Microb Cell Fact ; 23(1): 202, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39026365

RESUMO

BACKGROUND: Microbial genome sequencing and analysis revealed the presence of abundant silent secondary metabolites biosynthetic gene clusters (BGCs) in streptomycetes. Activating these BGCs has great significance for discovering new compounds and novel biosynthetic pathways. RESULTS: In this study, we found that ovmZ and ovmW homologs, a pair of interdependent transcriptional regulators coding genes, are widespread in actinobacteria and closely associated with the biosynthesis of secondary metabolites. Through co-overexpression of native ovmZ and ovmW in Streptomyces neyagawaensis NRRL B-3092, a silent type II polyketide synthase (PKS) gene cluster was activated to produce gephyromycin A, tetrangomycin and fridamycin E with the yields of 22.3 ± 8.0 mg/L, 4.8 ± 0.5 mg/L and 20.3 ± 4.1 mg/L respectively in the recombinant strain of S.ne/pZnWn. However, expression of either ovmZ or ovmW failed to activate this gene cluster. Interestingly, overexpression of the heterologous ovmZ and ovmW pair from oviedomycin BGC of S. ansochromogenes 7100 also led to awakening of this silent angucyclinone BGC in S. neyagawaensis. CONCLUSION: A silent angucyclinone BGC was activated by overexpressing both ovmZ and ovmW in S. neyagawaensis. Due to the wide distribution of ovmZ and ovmW in the BGCs of actinobacteria, co-overexpression of ovmZ and ovmW could be a strategy for activating silent BGCs, thus stimulating the biosynthesis of secondary metabolites.


Assuntos
Antraquinonas , Antibacterianos , Família Multigênica , Streptomyces , Streptomyces/genética , Streptomyces/metabolismo , Antibacterianos/biossíntese , Antraquinonas/metabolismo , Regulação Bacteriana da Expressão Gênica , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Vias Biossintéticas/genética , Policetídeo Sintases/genética , Policetídeo Sintases/metabolismo , Metabolismo Secundário/genética , Anguciclinas e Anguciclinonas
3.
J Proteome Res ; 22(6): 1779-1789, 2023 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-37191251

RESUMO

Although diabetic nephropathy (DN) is the leading cause of the end-stage renal disease, the exact regulation mechanisms remain unknown. In this study, we integrated the transcriptomics and proteomics profiles of glomeruli isolated from 50 biopsy-proven DN patients and 25 controls to investigate the latest findings about DN pathogenesis. First, 1152 genes exhibited differential expression at the mRNA or protein level, and 364 showed significant association. These strong correlated genes were divided into four different functional modules. Moreover, a regulatory network of the transcription factors (TFs)-target genes (TGs) was constructed, with 30 TFs upregulated at the protein levels and 265 downstream TGs differentially expressed at the mRNA levels. These TFs are the integration centers of several signal transduction pathways and have tremendous therapeutic potential for regulating the aberrant production of TGs and the pathological process of DN. Furthermore, 29 new DN-specific splice-junction peptides were discovered with high confidence; these peptides may play novel functions in the pathological course of DN. So, our in-depth integrative transcriptomics-proteomics analysis provided deeper insights into the pathogenesis of DN and opened the potential avenue for finding new therapeutic interventions. MS raw files were deposited into the proteomeXchange with the dataset identifier PXD040617.


Assuntos
Diabetes Mellitus , Nefropatias Diabéticas , Humanos , Nefropatias Diabéticas/genética , Multiômica , Perfilação da Expressão Gênica , Fatores de Transcrição/genética , RNA Mensageiro
4.
Genome Res ; 30(2): 263-275, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32051188

RESUMO

Liver organogenesis and development are composed of a series of complex, well-orchestrated events. Identifying key factors and pathways governing liver development will help elucidate the physiological and pathological processes including those of cancer. We conducted multidimensional omics measurements including protein, mRNA, and transcription factor (TF) DNA-binding activity for mouse liver tissues collected from embryonic day 12.5 (E12.5) to postnatal week 8 (W8), encompassing major developmental stages. These data sets reveal dynamic changes of core liver functions and canonical signaling pathways governing development at both mRNA and protein levels. The TF DNA-binding activity data set highlights the importance of TF activity in early embryonic development. A comparison between mouse liver development and human hepatocellular carcinoma (HCC) proteomic profiles reveal that more aggressive tumors are characterized with the activation of early embryonic development pathways, whereas less aggressive ones maintain liver function-related pathways that are elevated in the mature liver. This work offers a panoramic view of mouse liver development and provides a rich resource to explore in-depth functional characterization.


Assuntos
Desenvolvimento Embrionário/genética , Fígado/crescimento & desenvolvimento , Proteoma/genética , Transcriptoma/genética , Animais , Carcinoma Hepatocelular/genética , Proteínas de Ligação a DNA/genética , Regulação da Expressão Gênica no Desenvolvimento/genética , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Fígado/metabolismo , Neoplasias Hepáticas/genética , Camundongos , RNA Mensageiro/genética , Fatores de Transcrição/genética
5.
Appl Microbiol Biotechnol ; 107(18): 5749-5760, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37486353

RESUMO

Cloning of large DNA fragments from microorganisms becomes increasingly important but remains seriously challenging due to the complexity and diversity of genetic background. In particular, the methods with high precision and efficiency are in great need for obtaining intact biosynthetic gene clusters (BGCs) of microbial natural products. Here, we report a new strategy for targeted cloning of large DNA fragments (TCLD) from different bacteria. Using this method, precise cloning of desired E. coli chromosomal fragments up to 201 kb was achieved with 53% positive rate. Moreover, its application in cloning of large BGCs with high G + C content and multiple repetitive sequences was also demonstrated, including the 98 kb tylosin BGC (tyl), 128 kb daptomycin BGC (dpt), and 127 kb salinomycin BGC (sal). Subsequently, heterologous expression of the cloned tyl BGC in Streptomyces coelicolor M1146 led to the production of tylosins in the resulting recombinant strains. And also, its introduction into Streptomyces fradiae ATCC 19609, a native producer of tylosin, effectively increased tylosin yield to 230%. Hence, TCLD is a powerful tool for cloning large BGCs and would facilitate the discovery of bioactive substances from microbial resources. KEY POINTS: • TCLD is an efficient method for cloning large DNA fragments. • Repeat sequence-mediated intra-molecular cyclization improves the cloning efficiency. • TCLD combined with scarless editing allows unlimited modifications on BGCs.


Assuntos
Streptomyces , Tilosina , Clonagem Molecular , Tilosina/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Streptomyces/genética , Streptomyces/metabolismo , Família Multigênica , DNA/genética , DNA/metabolismo
6.
Blood Purif ; 51(4): 345-354, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34284380

RESUMO

BACKGROUND: Hyponatremia is one of the most common disorders of electrolytes. Some research studies reported that hyponatremia was closely associated with mortality in patients with dialysis. However, this viewpoint remains controversial. OBJECTIVE: We aimed to do a systematic review and meta-analysis to assess the influence of hyponatremia on mortality in patients with dialysis. METHODS: We identified the eligible studies that investigated the association between hyponatremia and mortality risk in patients under dialysis by searching systematically a series of databases including PubMed, Embase, Cochrane, Web of science, and Ovid from January 2011 to June 2020. Adjusted hazard ratios (HRs) with 95% confidence intervals (95% CIs) were pooled. RESULTS: From 1,116 records identified, 12 studies including prospective and retrospective cohort studies met our inclusion criteria. We found hyponatremia both at baseline (HR: 1.50 and 95% CI: 1.41-1.59) and in time-varying (HR: 1.63 and 95% CI: 1.44-1.84) were significantly correlated to all-cause mortality after multivariable adjusted. By the subgroup analysis, the same results were presented in hemodialysis (HR: 1.48 and 95% CI: 1.38-1.59) or peritoneal dialysis patients (HR: 1.52 and 95% CI: 1.37-1.70). We also observed that lower serum sodium was independently associated with cardiovascular death. CONCLUSIONS: Hyponatremia was independently associated with all-cause and cardiovascular mortality, and it might predict adverse outcomes of patients under dialysis.


Assuntos
Doenças Cardiovasculares , Hiponatremia , Humanos , Estudos Prospectivos , Diálise Renal/efeitos adversos , Estudos Retrospectivos
7.
Anal Chem ; 93(32): 11191-11199, 2021 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-34355888

RESUMO

Heparan sulfates (HSs) are widely expressed glycans in the animal kingdom. HS plays a role in regulating cell differentiation/proliferation, embryonic development, blood coagulation, inflammatory response, and viral infection. The amount of HS and its structural information are critically important for investigating the functions of HS in vivo. A sensitive and reliable quantitative technique for the analysis of HS from biological samples is under development. Here, we report a new labeling reagent for HS disaccharides analysis, 6-amino-N-(2-diethylamino)ethyl quinoline-2-carboamide (AMQC). The AMQC-conjugated disaccharides are analyzed by LC-MS/MS in positive mode, significantly improving the sensitivity. The use of AMQC coupled with authentic 13C-labeled HS disaccharide internal standards empowered us to determine the amount and the disaccharide composition of the HS on a single histological slide. We used this method to profile the levels of HS in the plasma/serum and tissues/organs to assist the disease prognosis in two animal models, including the acetaminophen (APAP)-induced acute liver injury mouse model and the burn injury mouse model. The method may uncover the roles of HS contributing to the diseases as well as provide a potential new set of biomarkers for disease diagnosis and prognosis.


Assuntos
Heparitina Sulfato , Espectrometria de Massas em Tandem , Animais , Biomarcadores , Cromatografia Líquida , Dissacarídeos , Camundongos
8.
Biochem Biophys Res Commun ; 543: 8-14, 2021 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-33493986

RESUMO

Paulomycins (PAUs) refer to a group of glycosylated antibiotics with attractive antibacterial activities against Gram-positive bacteria. They contain a special ring A moiety that is prone to dehydrate between C-4 and C-5 to a quinone-type form at acidic condition, which will reduce the antibacterial activities of PAUs significantly. Elucidation of the biosynthetic mechanism of the ring A moiety may facilitate its structure modifications by combinatorial biosynthesis to generate PAU analogues with enhanced bioactivity or stability. Previous studies showed that the ring A moiety is derived from chorismate, which is converted to 3-hydroxyanthranilic acid (3-HAA) by a 2-amino-2-deoxyisochorismate (ADIC) synthase, a 2,3-dihydro-3-hydroxyanthranilic acid (DHHA) synthase, and a DHHA dehydrogenase. Unfortunately, little is known about the conversion process from 3-HAA to the highly decorated ring A moiety of PAUs. In this work, we characterized Pau17 as an unprecedented 3-HAA 6-hydroxylase responsible for the conversion of 3-HAA to 3,6-DHAA by in vivo and in vitro studies, pushing one step forward toward elucidating the biosynthetic mechanism of the ring A moiety of PAUs.


Assuntos
Ácido 3-Hidroxiantranílico/metabolismo , Antibacterianos/biossíntese , Cicloexenos/metabolismo , Dissacarídeos/biossíntese , Oxigenases de Função Mista/metabolismo , Streptomyces/enzimologia , Ácido 3-Hidroxiantranílico/química , Antibacterianos/química , Antibacterianos/farmacologia , Cicloexenos/química , Cicloexenos/farmacologia , Dissacarídeos/química , Dissacarídeos/farmacologia , Bactérias Gram-Positivas/efeitos dos fármacos , Oxigenases de Função Mista/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Streptomyces/química , Streptomyces/genética
9.
BMC Cancer ; 19(1): 276, 2019 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-30922256

RESUMO

BACKGROUND: The efficacy of bevacizumab combined with erlotinib (B + E) for the treatment of advanced hepatocellular carcinoma, especially for sorafenib-refractory patients, has been observed and evaluated in several trials. We conducted this single arm meta-analysis to generally assess the benefit and risk with B + E for advanced hepatocellular carcinoma. METHODS: The PubMed, Cochrane Library, Embase, ScienceDirect, Web of Science and Scopus databases were searched for related studies. The main outcomes were objective response rate (ORR), disease control rate (DCR), overall survival (OS), progression-free survival (PFS) and adverse effects (AEs). RESULTS: Eight phase II clinical trials including 342 hepatocellular carcinoma patients were analyzed. The pooled ORR was 12.6% (95% CI: 6.3-19.0%), and the pooled DCR was 54.5% (95% CI: 48.9-66.8%). The 16-week PFS rate was 50.2% (95% CI: 38.2-62.2%). The 6- and 12-month OS rates were 77.8% (95% CI: 71.3-84.2%) and 44.9% (95% CI: 36.8-53.0%). The main grade 3-4 AEs were fatigue (11.9%), diarrhea (9.0%), hypertension (6.7%), acne (5.8%) and hemorrhage (5.3%). The only RCT showed that the B + E regimen had a consistent response and equable median OS but fewer toxicities (grade 3-4 AEs: 19% vs. 27%) than sorafenib. Subgroup analysis showed that as a second-line treatment, the B + E regimen had substantial value with a favorable PFS-16w (P = 0.012), OS-12 m (P = 0.048) and a favorable tendency of ORR (P = 0.089), but obvious toxicities in the second-line setting could not be neglected. CONCLUSION: Bevacizumab combined with erlotinib is effective for treating hepatocellular carcinoma patients, especially sorafenib-refractory patients. More well-designed and large-scale RCTs are warranted to prove our findings.


Assuntos
Bevacizumab/administração & dosagem , Carcinoma Hepatocelular/tratamento farmacológico , Cloridrato de Erlotinib/administração & dosagem , Neoplasias Hepáticas/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Bevacizumab/efeitos adversos , Ensaios Clínicos Fase II como Assunto , Cloridrato de Erlotinib/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Análise de Sobrevida , Resultado do Tratamento
10.
Med Sci Monit ; 25: 2032-2042, 2019 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-30886134

RESUMO

BACKGROUND This systematic review of the literature and meta-analysis aimed to review the evaluation and monitoring of superoxide dismutase (SOD) activity and its clinical significance in gastric cancer. MATERIAL AND METHODS Systematic review involved searching the PubMed, Embase, Ovid, and the China National Knowledge Infrastructure (CNKI) databases. Search terms included 'superoxide dismutase,' and 'gastric cancer.' Studies that included measurements of SOD activity in peripheral blood samples in patients with SOD activity compared with healthy controls. The study was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. RESULTS Ten controlled clinical studies were identified that included six studies that measured SOD in serum, three in erythrocytes, and one study that measured SOD on whole blood. Meta-analysis, using the standardized mean difference (SMD) and the 95% confidence interval (CI), showed that patients with gastric cancer had significantly decreased SOD activity when compared with the healthy controls (SMD, -0.840; 95% CI, -1.463 to -0.218; p=0.008). Subgroup analysis was conducted on SOD distribution in the blood (erythrocyte: SMD, -1.773; 95% CI, -2.504 to -1.042; p=0.000) (serum SMD, -0.322; 95% CI, -1.006-0.361; p=0.355) (whole blood: SMD, -1.251; 95% CI, -1.731 to -0.771; p=0.000) and for male subjects (SMD, -2.090; 95% CI, -2.725 to -1.456; p<0.001). CONCLUSIONS Meta-analysis showed that SOD measurements from blood samples, especially in erythrocytes, had potential as a diagnostic and monitoring parameter in patients with gastric cancer.


Assuntos
Neoplasias Gástricas/enzimologia , Superóxido Dismutase/metabolismo , Biomarcadores Tumorais/sangue , Feminino , Humanos , Masculino , Neoplasias Gástricas/sangue , Superóxido Dismutase/sangue , Superóxido Dismutase-1/sangue , Superóxido Dismutase-1/metabolismo
11.
Biotechnol Bioeng ; 114(4): 852-861, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27800599

RESUMO

We previously demonstrated anaerobic conversion of the greenhouse gas methane into acetate using an engineered archaeon that produces methyl-coenzyme M reductase (Mcr) from unculturable microorganisms from a microbial mat in the Black Sea to create the first culturable prokaryote that reverses methanogenesis and grows anaerobically on methane. In this work, we further engineered the same host with the goal of converting methane into butanol. Instead, we discovered a process for converting methane to a secreted valuable product, L-lactate, with sufficient optical purity for synthesizing the biodegradable plastic poly-lactic acid. We determined that the 3-hydroxybutyryl-CoA dehydrogenase (Hbd) from Clostridium acetobutylicum is responsible for lactate production. This work demonstrates the first metabolic engineering of a methanogen with a synthetic pathway; in effect, we produce a novel product (lactate) from a novel substrate (methane) by cloning the three genes for Mcr and one for Hbd. We further demonstrate the utility of anaerobic methane conversion with an increased lactate yield compared to aerobic methane conversion to lactate. Biotechnol. Bioeng. 2017;114: 852-861. © 2016 Wiley Periodicals, Inc.


Assuntos
Ácido Láctico/metabolismo , Engenharia Metabólica/métodos , Metano/metabolismo , Methanosarcina/metabolismo , Butanóis/metabolismo , Ácido Láctico/análise , Methanosarcina/genética , Estereoisomerismo
12.
Angew Chem Int Ed Engl ; 56(39): 11784-11787, 2017 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-28731518

RESUMO

Chondroitin sulfate (CS) is a sulfated polysaccharide that plays essential physiological roles. Here, we report an enzyme-based method for the synthesis of a library of 15 different CS oligosaccharides. This library covers 4-O-sulfated and 6-O-sulfated oligosaccharides ranging from trisaccharides to nonasaccharides. We also describe the synthesis of unnatural 6-O-sulfated CS pentasaccharides containing either a 6-O-sulfo-2-azidogalactosamine or a 6-O-sulfogalactosamine residue. The availability of structurally defined CS oligosaccharides offers a novel approach to investigate the biological functions of CS.


Assuntos
Sulfatos de Condroitina/síntese química , Oligossacarídeos/síntese química , Sulfotransferases/química , Sequência de Carboidratos , Sulfatos de Condroitina/química , Cromatografia Líquida de Alta Pressão/métodos , Espectroscopia de Ressonância Magnética/métodos , Oligossacarídeos/química , Espectrometria de Massas por Ionização por Electrospray , Relação Estrutura-Atividade , Especificidade por Substrato
13.
Appl Microbiol Biotechnol ; 100(9): 4189-99, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26754814

RESUMO

Many novel microbial nature products were discovered from Actinobacteria by genome mining methods. However, only a few number of genome mining works were carried out in rare actinomycetes. An important reason precluding the genome mining efforts in rare actinomycetes is that most of them are recalcitrant to genetic manipulation. Herein, we chose the rare marine actinomycete Streptosporangium sp. CGMCC 4.7309 to explore its secondary metabolite diversity by genome mining. The genetic manipulation method has never been established for Streptosporangium strains. At first, we set up the genetic system of Streptosporangium sp. CGMCC 4.7309 unprecedentedly. The draft genome sequencing of Streptosporangium sp. CGMCC 4.7309 revealed that it contains more than 20 cryptic secondary metabolite biosynthetic clusters. A type II polyketide synthases-containing cluster (the hex cluster) was predicted to encode compounds with a pentangular polyphenol scaffold by in silico analysis. The products of the hex cluster were uncovered by comparing the metabolic profile of Streptosporangium sp. CGMCC 4.7309 with that of the hex30 inactivated mutant, in which a key ketoreductase gene was disrupted. Finally, three pentangular polyphenols were isolated and named as hexaricins A (1), B (2), and C (3). The inconsistency of the stereochemistry of C-15 in hexaricins A, B, and C indicates a branch point in their biosynthesis. Finally, the biosynthetic pathway of the hexaricins was proposed based on bioinformatics analysis.


Assuntos
Actinobacteria/química , Organismos Aquáticos/química , Polifenóis/isolamento & purificação , Biologia Computacional , Mineração de Dados , Genoma Bacteriano , Redes e Vias Metabólicas/genética , Metabolômica , Família Multigênica , Polifenóis/química , Polifenóis/classificação , Análise de Sequência de DNA
14.
PLoS Genet ; 9(9): e1003757, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24039601

RESUMO

Genome-wide gene expression profiles accumulate at an alarming rate, how to integrate these expression profiles generated by different laboratories to reverse engineer the cellular regulatory network has been a major challenge. To automatically infer gene regulatory pathways from genome-wide mRNA expression profiles before and after genetic perturbations, we introduced a new Bayesian network algorithm: Deletion Mutant Bayesian Network (DM_BN). We applied DM_BN to the expression profiles of 544 yeast single or double deletion mutants of transcription factors, chromatin remodeling machinery components, protein kinases and phosphatases in S. cerevisiae. The network inferred by this method identified causal regulatory and non-causal concurrent interactions among these regulators (genetically perturbed genes) that are strongly supported by the experimental evidence, and generated many new testable hypotheses. Compared to networks reconstructed by routine similarity measures or by alternative Bayesian network algorithms, the network inferred by DM_BN excels in both precision and recall. To facilitate its application in other systems, we packaged the algorithm into a user-friendly analysis tool that can be downloaded at http://www.picb.ac.cn/hanlab/DM_BN.html.


Assuntos
Biologia Computacional , Perfilação da Expressão Gênica , Redes Reguladoras de Genes , Deleção de Sequência/genética , Algoritmos , Teorema de Bayes , Expressão Gênica , Análise de Sequência com Séries de Oligonucleotídeos , Monoéster Fosfórico Hidrolases/genética , Proteínas Quinases/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Transdução de Sinais
15.
Wei Sheng Wu Xue Bao ; 56(3): 363-72, 2016 Mar 04.
Artigo em Chinês | MEDLINE | ID: mdl-27382780

RESUMO

Streptothricins are a group of the earliest discovered antibiotics with broad antimicrobial spectrum, and have been used for crop protection. We reviewed the studies on streptothricin resistance, biosynthesis of the three components (streptolidine, carbamoylated D-glucosamine and poly ß-lysine chain) and chemical synthesis of streptothricins. The important aspects for future streptothricin researches were also discussed.


Assuntos
Antibacterianos/biossíntese , Streptomyces/metabolismo , Estreptotricinas/biossíntese , Antibacterianos/química , Microbiologia Industrial , Estrutura Molecular , Streptomyces/genética , Estreptotricinas/química
16.
Appl Microbiol Biotechnol ; 99(4): 1923-33, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25666782

RESUMO

Streptomyces is studied intensively for its outstanding ability to produce bioactive secondary metabolites and for its complicated morphological differentiation process. A classical genetic manipulation system for Streptomyces has been developed and widely used in the community for a long time, using antibiotic resistance markers to select for double-crossover mutants. The screening process is always laborious and time-consuming. However, the lack of a suitable chromogenic reporter for Streptomyces has limited the use of color-based screening system to simplify the selection process for double-crossover mutants. In this study, a blue reporter system for Streptomyces has been established by mining an indigoidine synthetase gene (idgS) from Streptomyces lavendulae CGMCC 4.1386, leading to the development of a time-saving gene inactivation system for Streptomyces by simple blue-white screening. A series of Streptomyces suicide and temperature-sensitive plasmids containing the idgS reporter cassette were constructed and used successfully to inactivate genes in Streptomyces, allowing a simple and efficient screening method to differentiate the colonies for double-crossover (white) and single-crossover (blue) mutants. Inactivation of the putative γ-butyrolactone synthase gene afsA-y via the idgS-based blue-white screening method revealed that the paulomycin production is negatively controlled by afsA-y in Streptomyces sp. YN86.


Assuntos
Inativação Gênica , Testes Genéticos/métodos , Genética Microbiana/métodos , Biologia Molecular/métodos , Streptomyces/genética , Streptomyces/isolamento & purificação , Cruzamentos Genéticos , DNA Bacteriano/química , DNA Bacteriano/genética , Genes Bacterianos , Genes Reporter , Vetores Genéticos , Dados de Sequência Molecular , Piperidonas/metabolismo , Plasmídeos , Recombinação Genética , Análise de Sequência de DNA
17.
Wei Sheng Wu Xue Bao ; 55(6): 707-18, 2015 Jun 04.
Artigo em Chinês | MEDLINE | ID: mdl-26562995

RESUMO

OBJECTIVE: We expressed a nikkomycin biosynthetic gene cluster in the well-characterized surrogate Streptomyces coelicolor M1146. METHODS: By using PCR-targeting method, we replaced the promoters of sanG and sanF in pNIK, which contains nikkomycin biosynthetic gene cluster, with the hrdB promoter to generate pNIKm. We transferred pNIK and pNIKm into S. coelicolor M1146 by intergeneric conjugation and obtained M1146-NIK and M1146-NIKm, respectively. We then evaluated expression of the gene cluster in the heterologous host by RT-PCR. Furthermore, we also compared the antifugal activity and nikkomycin production of M1146-NIK and M1146-NIKm by bioassay against Alternaria longipes and HPLC analysis. RESULTS: M1146-NIK and M1146-NIKm exhibited antifungal activity, and they can produce a trace amount of nikkomycin X, nikkomycin Z and pseudo-Z. There was a substantial accumulation of uridine in M1146-NIK, whereas substantial accumulations of uridine, ribofuranosyl-4-formyl-4-imidazolone and pyridylhomothreonine were observed in M1146-NIKm. CONCLUSION: We successfully expressed the nikkomycin biosynthetic gene cluster in the heterologous host and identified nikkomycins and some of its key biosynthetic intermediates. This study will provide the basis for enzymatic reaction of the condensation between the two nikkomycin moieties and for the generation of hybrid antibiotics by combinatorial biosynthesis.


Assuntos
Aminoglicosídeos/biossíntese , Antifúngicos/metabolismo , Proteínas de Bactérias/genética , Streptomyces/genética , Streptomyces/metabolismo , Aminoglicosídeos/química , Antifúngicos/química , Proteínas de Bactérias/metabolismo , Clonagem Molecular , Engenharia Metabólica , Família Multigênica , Regiões Promotoras Genéticas
18.
Angew Chem Int Ed Engl ; 54(17): 5175-8, 2015 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-25728237

RESUMO

Streptothricins (STNs) are atypical aminoglycosides containing a rare carbamoylated D-gulosamine (D-GulN) moiety, and the antimicrobial activity of STNs has been exploited for crop protection. Herein, the biosynthetic pathway of the carbamoylated D-GulN moiety was delineated. An N-acetyl-D-galactosamine is first attached to the streptolidine lactam by the glycosyltransferse StnG and then epimerized to N-acetyl-D-gulosamine by the putative epimerase StnJ. After carbamoylation by the carbamoyltransferase StnQ, N-acetyl-D-GulN is deacetylated by StnI to furnish the carbamoylated D-GulN moiety. In vitro studies characterized two novel enzymes: StnG is an unprecedented GT-A fold N-glycosyltransferase that glycosylates the imine nitrogen atom of guanidine, and StnI is the first reported N-acetyl-D-GulN deacetylase.


Assuntos
Carboxil e Carbamoil Transferases/metabolismo , Glicosiltransferases/metabolismo , Estreptotricinas/biossíntese , Antibacterianos/biossíntese , Antibacterianos/química , Antibacterianos/farmacologia , Glicosilação , Família Multigênica , Pseudomonas aeruginosa/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Streptomyces/genética , Estreptotricinas/química , Estreptotricinas/farmacologia
19.
Prim Care Diabetes ; 18(3): 268-276, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38555202

RESUMO

BACKGROUND: Based on the rapidly growing global burden of non-alcoholic fatty liver disease (NAFLD) or steatohepatitis (NASH), in order to evaluate the efficacy of glucagon-like peptide-1 receptor agonists (GLP-1RAs) in the treatment of NAFLD or NASH this paper presents a systematic review and meta-analysis of randomized controlled trials(RCTs). METHODS: In this systematic review and meta-analysis, We searched PubMed, Medline, Web of Science and The Cochrane Library databases. All randomized controlled trials involving GLP-1RAs and NAFLD or NASH were collected since the database was established. A meta-analysis of proportions was done with the generalised linear mixed model. Continuous variables were represented by Mean and Standard Deviation (SD), and binary variable were represented by Relative Risk (RR) and 95% Confidence Interval (CI) as effect indicators. The research results were presented by Revman 5.4. This study is registered with PROSPERO (CRD42023390735). FINDING: We included 16 placebo-controlled or active drug-controlled randomized controlled trials (involving 2178 patients) that used liraglutide, exenatide, dulaglutide, or semaglutie in the treatment of NAFLD or NASH, as measured by liver biopsy or imaging techniques. This study found that the effect of GLP-1RAs on histologic resolution of NASH with no worsening of liver fibrosis (n=2 RCTs; WMD:4.08, 95%CI 2.54-6.56, p < 0.00001) has statistically significant. At the same time, GLP-1RAs affected CRP (n = 7 RCTs; WMD:-0.41, 95% CI-0.78 to -0.04, p =0.002) and other serological indicators were significantly improved. CONCLUSION: This study evaluated the efficacy of GLP-1RAs in patients with NAFLD and NASH. These results suggest that GLP-1RAs may be a potential and viable therapeutic approach as a targeted agent to intervene in disease progression of NAFLD and NASH.


Assuntos
Biomarcadores , Proteína C-Reativa , Receptor do Peptídeo Semelhante ao Glucagon 1 , Incretinas , Cirrose Hepática , Hepatopatia Gordurosa não Alcoólica , Ensaios Clínicos Controlados Aleatórios como Assunto , Humanos , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/sangue , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Resultado do Tratamento , Biomarcadores/sangue , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/diagnóstico , Incretinas/uso terapêutico , Incretinas/efeitos adversos , Proteína C-Reativa/metabolismo , Proteína C-Reativa/análise , Masculino , Feminino , Pessoa de Meia-Idade , Hipoglicemiantes/uso terapêutico , Adulto , Fígado/patologia , Fígado/efeitos dos fármacos , Fatores de Risco , Índice de Gravidade de Doença , Idoso , Proteínas Recombinantes de Fusão/uso terapêutico , Fragmentos Fc das Imunoglobulinas/uso terapêutico , Liraglutida/uso terapêutico , Peptídeos Semelhantes ao Glucagon/uso terapêutico , Peptídeos Semelhantes ao Glucagon/análogos & derivados , Peptídeos Semelhantes ao Glucagon/efeitos adversos , Agonistas do Receptor do Peptídeo 1 Semelhante ao Glucagon
20.
Heliyon ; 10(11): e32460, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38933931

RESUMO

Objective: Recent studies have shown that gene alternative splicing (AS) and long noncoding RNAs (lncRNAs) are involved in diabetes mellitus (DM) and its complications. Currently, myo-inositol (MI) is considered as effective for the treatment of insulin resistance and lipid metabolism disorders in diabetes patients. We hope to better explore the potential roles of gene AS and lncRNAs in liver glucose and lipid metabolism in diabetes, as well as the effects of myo-inositol treatment, through transcriptome analysis. Methods: This study analysed glucose and lipid metabolism-related biochemical indicators and liver HE staining in four groups of mice: the control group (Ctrl group), the diabetes group (DM group), the myo-inositol treatment group (MI group), and the metformin treatment group (Met group). The changes in relevant gene-regulated alternative splicing events (RASEs) and lncRNAs were analysed by RNA sequencing of liver tissue, and coexpression analysis and functional enrichment analysis were used to predict the possible lncRNAs and RASEs involved in liver glucose and lipid metabolism. Result: Metformin and myo-inositol alleviated insulin resistance, lipid metabolism disorders, and hepatic steatosis in diabetic mice. Transcriptome sequencing analysis revealed differential splicing events of genes related to lipid metabolism and differentially expressed lncRNAs (DElncRNAs). Six different lncRNAs and their potentially interacting splicing events were predicted. Conclusion: The present study revealed novel changes in RASEs and lncRNAs in the livers of diabetic mice following treatment with myo-inositol, which may shed light on the potential mechanisms by which myo-inositol delays and treats the progression of hepatic glucose and lipid metabolism in diabetes.

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