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1.
Chem Biodivers ; 18(11): e2100674, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34609053

RESUMO

Chemical investigation on a Streptomyces sp. strain MS180069 isolated from a sediment sample collected from the South China Sea, yielded the new benzo[f]isoindole-dione alkaloid, bhimamycin J (1). The structure was determined by extensive spectroscopic analysis, including HRMS, 1D, 2D NMR, and X-ray diffraction techniques. A molecular docking study revealed 1 as a new molecular motif that binds with human angiotensin converting enzyme2 (ACE2), recently described as the cell surface receptor responsible for uptake of 2019-CoV-2. Using enzyme assays we confirm that 1 inhibits human ACE2 79.7 % at 25 µg/mL.


Assuntos
Alcaloides/química , Sedimentos Geológicos/microbiologia , Isoindóis/química , Streptomyces/química , Alcaloides/metabolismo , Alcaloides/farmacologia , Alcaloides/uso terapêutico , Enzima de Conversão de Angiotensina 2/antagonistas & inibidores , Enzima de Conversão de Angiotensina 2/metabolismo , Sítios de Ligação , COVID-19/tratamento farmacológico , COVID-19/virologia , Fungos/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Humanos , Isoindóis/isolamento & purificação , Isoindóis/metabolismo , Isoindóis/farmacologia , Espectroscopia de Ressonância Magnética , Conformação Molecular , Simulação de Acoplamento Molecular , SARS-CoV-2/isolamento & purificação , Streptomyces/isolamento & purificação , Streptomyces/metabolismo
2.
Chem Pharm Bull (Tokyo) ; 69(10): 1034-1038, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34602572

RESUMO

Spiroviolene is a spirocyclic triquinane diterpene produced by Streptomyces violens. Recently, a biosynthetic pathway that includes secondary carbocation intermediates and a complicated concerted skeletal rearrangement was proposed for spiroviolene, based upon careful labeling experiments. On the basis of density functional theory (DFT) calculations, we propose a revised pathway for spiroviolene biosynthesis, involving a multistep carbocation cascade that bypasses the formation of unstable secondary carbocations by breaking the adjacent C-C bond to form a more stable tertiary carbocation (IM3) and by Wagner-Meerwein 1,2-methyl rearrangement (IM7).


Assuntos
Compostos de Espiro/metabolismo , Streptomyces/química , Teoria da Densidade Funcional , Conformação Molecular , Compostos de Espiro/química , Streptomyces/metabolismo
3.
Molecules ; 26(19)2021 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-34641466

RESUMO

Peptide natural products displaying a wide range of biological activities have become important drug candidates over the years. Microorganisms have been a powerful source of such bioactive peptides, and Streptomyces have yielded many novel natural products thus far. In an effort to uncover such new, meaningful compounds, the metabolome of Streptomyces acidiscabies was analyzed thoroughly. Three new compounds, scabimycins A-C (1-3), were discovered, and their chemical structures were elucidated by NMR spectroscopy. The relative and absolute configurations were determined using ROESY NMR experiments and advanced Marfey's method.


Assuntos
Produtos Biológicos/farmacologia , Metaboloma/efeitos dos fármacos , Fragmentos de Peptídeos/farmacologia , Streptomyces/metabolismo , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Streptomyces/efeitos dos fármacos
4.
Molecules ; 26(19)2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-34641580

RESUMO

In the present study, Streptomyces rimosus was confronted with Streptomyces noursei, Penicillium rubens, Aspergillus niger, Chaetomium globosum, or Mucor racemosus in two-species submerged co-cultures in shake flasks with the goal of evaluating the oxytetracycline production and morphological development. The co-culture of S. rimosus with S. noursei exhibited stimulation in oxytetracycline biosynthesis compared with the S. rimosus monoculture, whereas the presence of M. racemosus resulted in a delay in antibiotic production. Different strategies of initiating the "S. rimosus + S. noursei" co-cultures were tested. The improvement in terms of oxytetracycline titers was recorded in the cases where S. noursei was co-inoculated with S. rimosus in the form of spores. As the observed morphological changes were not unique to the co-culture involving S. noursei, there was no evidence that the improvement of oxytetracycline levels could be attributed mainly to morphology-related characteristics.


Assuntos
Oxitetraciclina/biossíntese , Streptomyces rimosus/metabolismo , Streptomyces/metabolismo , Antibacterianos/biossíntese , Técnicas de Cocultura , Esporos Bacterianos , Streptomyces/citologia , Streptomyces rimosus/citologia
5.
World J Microbiol Biotechnol ; 37(10): 171, 2021 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-34490503

RESUMO

Filamentous microorganisms are potent sources of bioactive secondary metabolites, the molecules formed in response to complex environmental signals. The chemical diversity encoded in microbial genomes is only partially revealed by following the standard microbiological approaches. Mimicking the natural stimuli through laboratory co-cultivation is one of the most effective methods of awakening the formation of high-value metabolic products. Whereas the biosynthetic outcomes of co-cultures are reviewed extensively, the bioprocess aspects of such efforts are often overlooked. The aim of the present review is to discuss the submerged co-cultivation strategies used for triggering and enhancing secondary metabolites production in Streptomyces, a heavily investigated bacterial genus exhibiting an impressive repertoire of secondary metabolites, including a vast array of antibiotics. The previously published studies on influencing the biosynthetic capabilities of Streptomyces through co-cultivation are comparatively analyzed in the bioprocess perspective, mainly with the focus on the approaches of co-culture initiation, the experimental setup, the design of experimental controls and the ways of influencing the outcomes of co-cultivation processes. These topics are discussed in the general context of secondary metabolites production in submerged microbial co-cultures by referring to the Streptomyces-related studies as illustrative examples.


Assuntos
Produtos Biológicos/metabolismo , Técnicas de Cocultura/métodos , Metabolismo Secundário , Streptomyces/metabolismo , Streptomyces/genética , Streptomyces/crescimento & desenvolvimento
6.
J Agric Food Chem ; 69(37): 11110-11120, 2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-34516129

RESUMO

The mechanism of active site loops of Streptomyces phospholipase D (PLD) binding to the lipid-water interface for catalytic reactions still remains elusive. A flexible loop (residues 376-382) in the active site of Streptomyces klenkii PLD (SkPLD) is conserved within PLDs in most of the Streptomyces species. The residue Ser380 was found to be essential for the enzyme's adsorption to the interface and its substrate recognition. The S380V mutant showed a 4.8 times higher catalytic efficiency and nearly seven times higher adsorption equilibrium coefficient compared to the wild-type SkPLD. The monolayer film technique has confirmed that the substitution of Ser380 with valine in the loop exhibited positive interaction between the enzyme and PCs with different acyl chain lengths. The results of the interfacial binding properties indicated that the S380V mutant might display suitable phosphatidylserine synthesis activity. The present study will be helpful to explain the role of residue 380 in the active site loops of Streptomyces PLD.


Assuntos
Fosfolipase D , Streptomyces , Domínio Catalítico , Interações Hidrofóbicas e Hidrofílicas , Fosfolipase D/genética , Fosfolipase D/metabolismo , Fosfolipídeos , Streptomyces/genética , Streptomyces/metabolismo , Especificidade por Substrato
7.
Mol Genet Genomics ; 296(6): 1299-1311, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34564766

RESUMO

A phylogenomic study conducted with different bioinformatic tools such as TYGS, REALPHY and AAI comparisons revealed a high rate of misidentified Streptomyces albus genomes in GenBank. Only 9 of the 18 annotated genomes available in the public database were correctly identified as S. albus species. The pangenome of the nine in silico confirmed S. albus genomes was almost closed. Lignocellulosic agroresidues were a common niche among strains of the S. albus clade while carbohydrate active enzymes (CAZymes) were highly conserved. Relevant enzymes for cellulose degradation such as beta glucosidases belonging to the GH1 family, a GH6 cellulase and a monooxygenase AA10-CBM2 were encoded by all S. albus genomes. Among them, one GH1 glycosidase would be regulated by CebR. However, this regulatory mechanism was not confirmed for other genes related to cellulose degradation. Based on AntiSMASH predictions, the core secondary metabolome of S. albus encompassed a total of 23 biosynthetic gene clusters (BGCs), where 4 were related to common metabolites within Streptomyces genus. Species specific BGCs included those related to pseudouridimycin and xantholipin. Additionally, four BGCs encoded putative derivatives of ibomycin, the lasso peptide SSV-2086, the lanthipeptide SapB and the terpene isorenieratene. Known metabolites could not be assigned to ten BGCs and three clusters did not match with any previously described BGC. The core genome of S. albus retrieved from nine closely related genomes revealed a high potential for the discovery of novel bioactive metabolites and underexplored regulatory genomic elements related to lignocellulose deconstruction.


Assuntos
Celulases/genética , Genoma Bacteriano/genética , Lignina/metabolismo , Streptomyces/genética , Streptomyces/metabolismo , Bases de Dados Genéticas , Glicosídeo Hidrolases/genética , Metaboloma/genética , Oxigenases de Função Mista/genética , Família Multigênica/genética , Filogenia , Metabolismo Secundário/genética
8.
Nat Commun ; 12(1): 5672, 2021 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-34584078

RESUMO

Nature forms S-S bonds by oxidizing two sulfhydryl groups, and no enzyme installing an intact hydropersulfide (-SSH) group into a natural product has been identified to date. The leinamycin (LNM) family of natural products features intact S-S bonds, and previously we reported an SH domain (LnmJ-SH) within the LNM hybrid nonribosomal peptide synthetase (NRPS)-polyketide synthase (PKS) assembly line as a cysteine lyase that plays a role in sulfur incorporation. Here we report the characterization of an S-adenosyl methionine (SAM)-dependent hydropersulfide methyltransferase (GnmP) for guangnanmycin (GNM) biosynthesis, discovery of hydropersulfides as the nascent products of the GNM and LNM hybrid NRPS-PKS assembly lines, and revelation of three SH domains (GnmT-SH, LnmJ-SH, and WsmR-SH) within the GNM, LNM, and weishanmycin (WSM) hybrid NRPS-PKS assembly lines as thiocysteine lyases. Based on these findings, we propose a biosynthetic model for the LNM family of natural products, featuring thiocysteine lyases as PKS domains that directly install a -SSH group into the GNM, LNM, or WSM polyketide scaffold. Genome mining reveals that SH domains are widespread in Nature, extending beyond the LNM family of natural products. The SH domains could also be leveraged as biocatalysts to install an -SSH group into other biologically relevant scaffolds.


Assuntos
Produtos Biológicos/metabolismo , Liases de Carbono-Enxofre/metabolismo , Cisteína/análogos & derivados , Metiltransferases/metabolismo , Policetídeo Sintases/metabolismo , Sulfetos/metabolismo , Animais , Produtos Biológicos/química , Cisteína/metabolismo , Cistina/química , Cistina/metabolismo , Humanos , Lactamas/síntese química , Lactamas/química , Lactamas/metabolismo , Macrolídeos/síntese química , Macrolídeos/química , Macrolídeos/metabolismo , Modelos Químicos , Estrutura Molecular , Peptídeo Sintases/metabolismo , Streptomyces/genética , Streptomyces/metabolismo , Especificidade por Substrato , Sulfetos/química , Tiazóis/síntese química , Tiazóis/química , Tiazóis/metabolismo , Tionas/síntese química , Tionas/química , Tionas/metabolismo , Domínios de Homologia de src
9.
Int J Mol Sci ; 22(17)2021 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-34502269

RESUMO

Biofilms formed by methicillin-resistant S. aureus (MRSA) are among the most frequent causes of biomedical device-related infection, which are difficult to treat and are often persistent and recurrent. Thus, new and effective antibiofilm agents are urgently needed. In this article, we review the most relevant literature of the recent years reporting on promising anti-MRSA biofilm agents derived from the genus Streptomyces bacteria, and discuss the potential contribution of these newly reported antibiofilm compounds to the current strategies in preventing biofilm formation and eradicating pre-existing biofilms of the clinically important pathogen MRSA. Many efforts are evidenced to address biofilm-related infections, and some novel strategies have been developed and demonstrated encouraging results in preclinical studies. Nevertheless, more in vivo studies with appropriate biofilm models and well-designed multicenter clinical trials are needed to assess the prospects of these strategies.


Assuntos
Biofilmes/efeitos dos fármacos , Equipamentos e Provisões/efeitos adversos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Infecções Relacionadas à Prótese/tratamento farmacológico , Infecções Estafilocócicas/tratamento farmacológico , Streptomyces/química , Streptomyces/metabolismo , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antibacterianos/uso terapêutico , Biofilmes/crescimento & desenvolvimento , Equipamentos e Provisões/microbiologia , Humanos , Staphylococcus aureus Resistente à Meticilina/fisiologia , Streptomyces/isolamento & purificação
10.
Nat Commun ; 12(1): 5221, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34471117

RESUMO

Bacteria of the genus Streptomyces are prolific producers of specialized metabolites, including antibiotics. The linear chromosome includes a central region harboring core genes, as well as extremities enriched in specialized metabolite biosynthetic gene clusters. Here, we show that chromosome structure in Streptomyces ambofaciens correlates with genetic compartmentalization during exponential phase. Conserved, large and highly transcribed genes form boundaries that segment the central part of the chromosome into domains, whereas the terminal ends tend to be transcriptionally quiescent compartments with different structural features. The onset of metabolic differentiation is accompanied by a rearrangement of chromosome architecture, from a rather 'open' to a 'closed' conformation, in which highly expressed specialized metabolite biosynthetic genes form new boundaries. Thus, our results indicate that the linear chromosome of S. ambofaciens is partitioned into structurally distinct entities, suggesting a link between chromosome folding, gene expression and genome evolution.


Assuntos
Antibacterianos/metabolismo , Cromossomos Bacterianos , Streptomyces/genética , Streptomyces/metabolismo , Estruturas Cromossômicas , Regulação Bacteriana da Expressão Gênica , Genoma Bacteriano , Família Multigênica , Transcriptoma
11.
Pol J Microbiol ; 70(2): 245-256, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34349814

RESUMO

Streptomyces is a genus with known biocontrol activity, producing a broad range of biologically active substances. Our goal was to isolate local Streptomyces species, evaluate their capacity to biocontrol the selected phytopathogens, and promote the plant growth via siderophore and indole acetic acid (IAA) production and phosphate solubilization. Eleven isolates were obtained from local soil samples in Saudi Arabia via the standard serial dilution method and identified morphologically by scanning electron microscope (SEM) and 16S rRNA amplicon sequencing. The biocontrol of phytopathogens was screened against known soil-borne fungi and bacteria. Plant growth promotion capacity was evaluated based on siderophore and IAA production and phosphate solubilization capacity. From eleven isolates obtained, one showed 99.77% homology with the type strain Streptomyces tricolor AS 4.1867, and was designated S. tricolor strain HM10. It showed aerial hyphae in SEM, growth inhibition of ten known phytopathogens in in vitro experiments, and the production of plant growth promoting compounds such as siderophores, IAA, and phosphate solubilization capacity. S. tricolor strain HM10 exhibited high antagonism against the fungi tested (i.e., Colletotrichum gloeosporides with an inhibition zone exceeding 18 mm), whereas the lowest antagonistic effect was against Alternaria solani (an inhibition zone equal to 8 mm). Furthermore, the most efficient siderophore production was recorded to strain HM8, followed by strain HM10 with 64 and 22.56 h/c (halo zone area/colony area), respectively. Concerning IAA production, Streptomyces strain HM10 was the most effective producer with a value of 273.02 µg/ml. An autochthonous strain S. tricolor HM10 should be an important biological agent to control phytopathogens and promote plant growth.


Assuntos
Fenômenos Fisiológicos Bacterianos , Fungos/fisiologia , Interações Microbianas/fisiologia , Plantas/microbiologia , Streptomyces/genética , Streptomyces/metabolismo , Bactérias/genética , Arábia Saudita , Streptomyces/classificação , Streptomyces/isolamento & purificação
12.
Sci Rep ; 11(1): 16649, 2021 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-34404820

RESUMO

A soluble melanin pigment produced by Streptomyces sp. ZL-24 was purified and named StrSM. The elemental analysis of StrSM showed it consists of carbon, hydrogen, and oxygen. The spectrum analysis, including ultraviolet-visible absorption spectrum, Fourier-transform infrared spectrum, and pyrolysis-gas chromatography-mass spectrometry, indicated that StrSM might be pyomelanin. High performance liquid chromatography and liquid chromatography-mass spectra analysis of intermediate metabolite showed the presence of homogentisic acid (HGA). Moreover, the enzyme 4-hydroxyphenylpyruvate dioxygenase, involved in HGA biosynthesis, showed high activity during melanin production. Subsequently, a tyrosinase gene (melC2) and hydroxyphenylpyruvate dioxygenase gene double mutant demonstrated StrSM is pyomelanin. In vitro bioactivity assay showed that StrSM had excellent protective capability against SH-SY5Y cell oxidative injury. To our knowledge, the results firstly provide comprehensive data on Streptomyces pyomelanin identification and a promising candidate compound to treat oxidative injury of neurocytes.


Assuntos
Peróxido de Hidrogênio/toxicidade , Melaninas/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Streptomyces/metabolismo , 4-Hidroxifenilpiruvato Dioxigenase/genética , Linhagem Celular Tumoral , Cromatografia Líquida de Alta Pressão/métodos , Humanos , Espectrometria de Massas/métodos , Melaninas/biossíntese , Melaninas/isolamento & purificação , Espectroscopia de Infravermelho com Transformada de Fourier/métodos
13.
Int J Mol Sci ; 22(14)2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-34299187

RESUMO

By culturing microorganisms under standard laboratory conditions, most biosynthetic gene clusters (BGCs) are not expressed, and thus, the products are not produced. To explore this biosynthetic potential, we developed a novel "semi-targeted" approach focusing on activating "silent" BGCs by concurrently introducing a group of regulator genes into streptomycetes of the Tübingen strain collection. We constructed integrative plasmids containing two classes of regulatory genes under the control of the constitutive promoter ermE*p (cluster situated regulators (CSR) and Streptomyces antibiotic regulatory proteins (SARPs)). These plasmids were introduced into Streptomyces sp. TÜ17, Streptomyces sp. TÜ10 and Streptomyces sp. TÜ102. Introduction of the CSRs-plasmid into strain S. sp. TÜ17 activated the production of mayamycin A. By using the individual regulator genes, we proved that Aur1P, was responsible for the activation. In strain S. sp. TÜ102, the introduction of the SARP-plasmid triggered the production of a chartreusin-like compound. Insertion of the CSRs-plasmid into strain S. sp. TÜ10 resulted in activating the warkmycin-BGC. In both recombinants, activation of the BGCs was only possible through the simultaneous expression of aur1PR3 and griR in S. sp. TÜ102 and aur1P and pntR in of S. sp. TÜ10.


Assuntos
Proteínas de Bactérias/genética , Benzo(a)Antracenos/metabolismo , Família Multigênica , Proteínas Recombinantes/genética , Streptomyces/genética , Proteínas de Bactérias/metabolismo , Benzopiranos , Regulação Bacteriana da Expressão Gênica , Glicosídeos/biossíntese , Regiões Promotoras Genéticas , Proteínas Recombinantes/metabolismo , Streptomyces/crescimento & desenvolvimento , Streptomyces/metabolismo , Fatores de Transcrição/metabolismo , Trissacarídeos/biossíntese
14.
Angew Chem Int Ed Engl ; 60(35): 19139-19143, 2021 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-34219345

RESUMO

A bioassay-guided fractionation led to the isolation of hangtaimycin (HTM) from Streptomyces spectabilis CCTCC M2017417 and the discovery of its hepatoprotective properties. Structure elucidation by NMR suggested the need for a structural revision. A putative HTM degradation product was also isolated and its structure was confirmed by total synthesis. The biosynthetic gene cluster was identified and resembles a hybrid trans-AT PKS/NRPS biosynthetic machinery whose first PKS enzyme contains an internal dehydrating bimodule, which is usually found split in other trans-AT PKSs. The mechanisms of such dehydrating bimodules have often been proposed, but have never been deeply investigated. Here we present in vivo mutations and in vitro enzymatic experiments that give first and detailed mechanistic insights into catalysis by dehydrating bimodules.


Assuntos
Aciltransferases/metabolismo , Policetídeos/metabolismo , Estrutura Molecular , Policetídeos/química , Streptomyces/química , Streptomyces/metabolismo
15.
Sci Rep ; 11(1): 14539, 2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-34267232

RESUMO

Streptomyces smyrnaeus UKAQ_23, isolated from the mangrove-sediment, collected from Jubail,Saudi Arabia, exhibited substantial antimicrobial activity against methicillin-resistant Staphylococcus aureus (MRSA), including non-MRSA Gram-positive test bacteria. The novel isolate, under laboratory-scale conditions, produced the highest yield (561.3 ± 0.3 mg/kg fermented agar) of antimicrobial compounds in modified ISP-4 agar at pH 6.5, temperature 35 °C, inoculum 5% v/w, agar 1.5% w/v, and an incubation period of 7 days. The two major compounds, K1 and K2, were isolated from fermented medium and identified as Actinomycin X2 and Actinomycin D, respectively, based on their structural analysis. The antimicrobial screening showed that Actinomycin X2 had the highest antimicrobial activity compared to Actinomycin D, and the actinomycins-mixture (X2:D, 1:1, w/w) against MRSA and non-MRSA Gram-positive test bacteria, at 5 µg/disc concentrations. The MIC of Actinomycin X2 ranged from 1.56-12.5 µg/ml for non-MRSA and 3.125-12.5 µg/ml for MRSA test bacteria. An in-silico molecular docking demonstrated isoleucyl tRNA synthetase as the most-favored antimicrobial protein target for both actinomycins, X2 and D, while the penicillin-binding protein-1a, was the least-favorable target-protein. In conclusion, Streptomyces smyrnaeus UKAQ_23 emerged as a promising source of Actinomycin X2 with the potential to be scaled up for industrial production, which could benefit the pharmaceutical industry.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Dactinomicina/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Streptomyces/metabolismo , Antibacterianos/isolamento & purificação , Antibacterianos/metabolismo , Simulação por Computador , Meios de Cultura/química , Dactinomicina/isolamento & purificação , Dactinomicina/metabolismo , Avaliação Pré-Clínica de Medicamentos/métodos , Fermentação , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Simulação de Acoplamento Molecular , Estrutura Molecular , Filogenia , Streptomyces/genética
16.
ACS Chem Biol ; 16(8): 1482-1492, 2021 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-34275291

RESUMO

Morphotype switches frequently occur in Actinobacteria and are often associated with disparate natural product production. Here, we report on differences in the secondary metabolomes of two morphotypes of a Streptomyces species, including the discovery of a novel antimicrobial glycosylated macrolide, which we named termidomycin A. While exhibiting an unusual 46-member polyene backbone, termidomycin A (1) shares structural features with the clinically important antifungal agents amphotericin B and nystatin A1. Genomic analyses revealed a biosynthetic gene cluster encoding for a putative giant type I polyketide synthase (PKS), whose domain structure allowed us to propose the relative configuration of the 46-member macrolide. The architecture of the biosynthetic gene cluster was different in both morphotypes, thus leading to diversification of the product spectrum. Given the high frequency of genomic rearrangements in Streptomycetes, the metabolic analysis of distinct morphotypes as exemplified in this study is a promising approach for the discovery of bioactive natural products and pathways of diversification.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Macrolídeos/farmacologia , Streptomyces/química , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antifúngicos/química , Antifúngicos/isolamento & purificação , Bactérias/efeitos dos fármacos , Fungos/efeitos dos fármacos , Genômica , Macrolídeos/química , Macrolídeos/isolamento & purificação , Metabolômica , Testes de Sensibilidade Microbiana , Família Multigênica , Policetídeo Sintases/genética , Policetídeo Sintases/metabolismo , Streptomyces/genética , Streptomyces/metabolismo
17.
Biochemistry ; 60(28): 2231-2235, 2021 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-34242001

RESUMO

Peptidyl nucleoside antifungals, represented by nikkomycins and polyoxins, consist of an unusual six-carbon nucleoside [aminohexuronic acid (AHA)] ligated to a nonproteinogenic amino acid via an amide bond. A recent study suggested that AHA is biosynthesized through cryptic phosphorylation, where a 2'-phosphate is introduced early in the pathway and required to form AHA. However, whether 2'-phosphorylation is necessary for the last step of biosynthesis, the formation of the amide bond between AHA and nonproteinogenic amino acids, remains ambiguous. Here, we address this question with comprehensive in vitro and in vivo characterizations of PolG and NikS, which together provide strong evidence that amide ligation proceeds with 2'-phosphorylated substrates in both pathways. Our results suggest that 2'-phosphorylation is retained for the entirety of both nikkomycin and polyoxin biosynthesis, providing important insights into how cryptic phosphorylation assists with nucleoside natural product biosynthesis.


Assuntos
Aminoglicosídeos/metabolismo , Antifúngicos/metabolismo , Streptomyces/metabolismo , Amidas/metabolismo , Vias Biossintéticas , Ácidos Hexurônicos/metabolismo , Fosforilação , Nucleosídeos de Pirimidina/metabolismo
18.
Commun Biol ; 4(1): 647, 2021 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-34059751

RESUMO

Streptomyces are one of the most important industrial microorganisms for the production of proteins and small-molecule drugs. Previously reported flow cytometry-based screening methods can only screen spores or protoplasts released from mycelium, which do not represent the filamentous stationary phase Streptomyces used in industrial cultivation. Here we show a droplet-based microfluidic platform to facilitate more relevant, reliable and rapid screening of Streptomyces mycelium, and achieved an enrichment ratio of up to 334.2. Using this platform, we rapidly characterized a series of native and heterologous constitutive promoters in Streptomyces lividans 66 in droplets, and efficiently screened out a set of engineered promoter variants with desired strengths from two synthetic promoter libraries. We also successfully screened out several hyperproducers of cellulases from a random S. lividans 66 mutant library, which had 69.2-111.4% greater cellulase production than the wild type. Our method provides a fast, simple, and powerful solution for the industrial engineering and screening of Streptomyces in more industry-relevant conditions.


Assuntos
Microfluídica/métodos , Micélio/metabolismo , Streptomyces/metabolismo , Ensaios de Triagem em Larga Escala/métodos , Engenharia Metabólica/métodos , Micélio/fisiologia , Regiões Promotoras Genéticas/genética , Streptomyces/genética , Streptomyces lividans/genética , Streptomyces lividans/metabolismo
19.
ACS Chem Neurosci ; 12(13): 2336-2346, 2021 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-34110771

RESUMO

Anhydroexfoliamycin, a secondary metabolite from Streptomyces, has shown antioxidant properties in primary cortical neurons reducing neurodegenerative hallmarks diseases, both in vitro and in vivo models. Activated microglia, in the central nervous system, plays a crucial role in neuroinflammation and is associated with neurodegeneration. Therefore, the aim of the present study was to determine the anti-inflammatory and antioxidant potential of the anhydroexfoliamycin over microglia BV2 cells. Neuroinflammation was simulated by incubation of microglia cells in the presence of lipopolysaccharide to activate proinflammatory transduction pathways. Moreover, a coculture of neuron SH-SY5Y and microglia BV2 cells was used to evaluate the neuroprotective properties of the Streptomyces metabolite. When microglia cells were preincubated with anhydroexfoliamycin, proinflammatory pathways, such as the translocation of the nuclear factor κB, the phosphorylation of c-Jun N-terminal kinase, and the inducible nitric oxide synthase expression, were inhibited. In addition, intracellular reactive oxygen species generation and the liberation of nitric oxide, interleukin 6, and tumor necrosis factor α were also decreased. Besides, the Streptomyces-derived compound showed antioxidant properties promoting the translocation of the factor erythroid 2-related factor 2 and protecting the SH-SY5Y cells from the neurotoxic mediators released by activated microglia. The effects of this compound were at the same level as the immunosuppressive drug cyclosporine A. Therefore, these results indicate that anhydroexfoliamycin is a promising tool to control microglia-driven inflammation with therapeutic potential in neuroinflammation.


Assuntos
Microglia , Streptomyces , Humanos , Inflamação/tratamento farmacológico , Mediadores da Inflamação , Lipopolissacarídeos/toxicidade , Microglia/metabolismo , NF-kappa B/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Streptomyces/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
20.
ACS Chem Biol ; 16(6): 1059-1069, 2021 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-34080843

RESUMO

C-Glycosylation in the biosynthesis of bioactive natural products is quite unique, which has not been studied well. Medermycin, as an antitumor agent in the family of pyranonaphthoquinone antibiotics, is featured with unique C-glycosylation. Here, a new C-glycosyltransferase (C-GT) Med-8 was identified to be essential for the biosynthesis of medermycin, as the first example of C-GT to recognize a rare deoxyaminosugar (angolosamine). med-8 and six genes (med-14, -15, -16, -17, -18, and -20 located in the medermycin biosynthetic gene cluster) predicted for the biosynthesis of angolosamine were proved to be functional and sufficient for C-glycosylation. A C-glycosylation cassette composed of these seven genes could convert a proposed substrate into a C-glycosylated product. In conclusion, these genes involved in the C-glycosylation of medermycin were functionally identified and biosynthetically engineered, and they provided the possibility of producing new C-glycosylated compounds.


Assuntos
Proteínas de Bactérias/metabolismo , Vias Biossintéticas , Glicosiltransferases/metabolismo , Streptomyces/metabolismo , Proteínas de Bactérias/genética , Genes Bacterianos , Glicosiltransferases/genética , Modelos Moleculares , Família Multigênica , Naftoquinonas/metabolismo , Filogenia , Streptomyces/genética
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