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1.
Artigo em Inglês | MEDLINE | ID: mdl-34242158

RESUMO

A novel actinomycete, designated NUM-2625T, was isolated as an endophytic bacterium in aerial parts of Comarum salesowianum, an endemic species in the Altai, Himalaya mountain chain area, collected from Khasagt Khairkhan Mountain in Mongolia. The 16S rRNA gene sequence of strain NUM-2625T showed the highest similarity to Actinocatenispora thailandica TT2-10T (99.4 %), Actinocatenispora sera KV-744T (99.3 %), and Actinocatenispora rupis CS5-AC17T (97.7 %). Chemotaxonomic properties of strain NUM-2625T were essentially consistent with those of the genus Actinocatenispora, such as the presence of meso-diaminopimelic acid as the diagnostic diamino acid of the peptidoglycan, MK-9(H4) and MK-9(H6) as the major menaquinones, and iso-C16 : 0, iso-C15 : 0, iso-C14 : 0 3-OH, and anteiso-C17 : 0 as the major fatty acids. Meanwhile, digital DNA-DNA hybridization and average nucleotide identity values revealed a low relatedness between strain NUM-2625T and the other type strains of the genus Actinocatenispora. In addition, strain NUM-2625T exhibited several phenotypic properties that could be used to distinguish it from its closest relatives. Based on the results of polyphasic analyses, strain NUM-2625T represents a novel species in the genus Actinocatenispora, for which the name Actinocatenispora comari sp. nov. is proposed. The type strain is NUM-2625T (=NBRC 114660T=TBRC 13496T).


Assuntos
Micromonosporaceae/classificação , Filogenia , Componentes Aéreos da Planta/microbiologia , Rosácea/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Endófitos/classificação , Endófitos/isolamento & purificação , Ácidos Graxos/química , Micromonosporaceae/isolamento & purificação , Mongólia , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
2.
Chin J Nat Med ; 19(7): 536-539, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34247777

RESUMO

Over-expression of the pathway specific positive regulator gene is an effective way to activate silent gene cluster. In the curret study, the SARP family regulatory gene, vasR2, was over-expressed in strain Verrucosispora sp. NS0172 and the cryptic gene cluster responsible for the biosynthesis of pentaketide ansamycin was partially activated. Two tetraketides (1 and 2) and a triketide (3) ansamycins, together with five known compounds (4-8), were isolated and elucidated from strain NS0172OEvasR2. Their NMR data were completely assigned by analysis of their HR-ESI-MS and 1H, 13C NMR, HMQC, HMBC and 1H-1H COSY spectra.


Assuntos
Micromonosporaceae , Policetídeos , Rifabutina/metabolismo , Micromonosporaceae/genética , Micromonosporaceae/metabolismo , Família Multigênica , Policetídeos/metabolismo
3.
Appl Microbiol Biotechnol ; 105(13): 5541-5551, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34189614

RESUMO

Rare actinomycetes are likely treasure troves for bioactive natural products, and it is therefore important that we enrich our understanding of biosynthetic potential of these relatively understudied bacteria. Dactylosporangium are a genus of such rare Actinobacteria that are known to produce a number of important antibacterial compounds, but for which there are still no fully assembled reference genomes, and where the extent of encoded biosynthetic capacity is not defined. Dactylosporangium vinaceum (NRRL B-16297) is known to readily produce a deep wine red-coloured diffusible pigment of unknown origin, and it was decided to define the chemical identity of this natural product pigment, and in parallel use whole genome sequencing and transcriptional analysis to lay a foundation for understanding the biosynthetic capacity of these bacteria. Results show that the produced pigment is made of various rubrolone conjugates, the spontaneous product of the reactive pre-rubrolone, produced by the bacterium. Genome and transcriptome analysis identified the highly expressed biosynthetic gene cluster (BGC) for pre-rubrolone. Further analysis of the fully assembled genome found it to carry 24 additional BGCs, of which the majority were poorly transcribed, confirming the encoded capacity of this bacterium to produce natural products but also illustrating the main bottleneck to exploiting this capacity. Finally, analysis of the potential environmental role of pre-rubrolone found it to react with a number of amine containing antibiotics, antimicrobial peptides and siderophores pointing to its potential role as a "minesweeper" of xenobiotic molecules in the bacterial environment. KEY POINTS: • D. vinaceum encodes many BGC, but the majority are transcriptionally silent. • Chemical screening identifies molecules that modulate rubrolone production. • Pre-rubrolone is efficient at binding and inactivating many natural antibiotics.


Assuntos
Actinobacteria , Produtos Biológicos , Micromonosporaceae , Actinobacteria/genética , Família Multigênica , Piridinas
4.
Microb Biotechnol ; 14(1): 291-306, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33280260

RESUMO

Filamentous members of the phylum Actinobacteria are a remarkable source of natural products with pharmaceutical potential. The discovery of novel molecules from these organisms is, however, hindered because most of the biosynthetic gene clusters (BGCs) encoding these secondary metabolites are cryptic or silent and are referred to as orphan BGCs. While co-culture has proven to be a promising approach to unlock the biosynthetic potential of many microorganisms by activating the expression of these orphan BGCs, it still remains an underexplored technique. The marine actinobacterium Salinispora tropica, for instance, produces valuable compounds such as the anti-cancer molecule salinosporamide but half of its putative BGCs are still orphan. Although previous studies have used marine heterotrophs to induce orphan BGCs in Salinispora, its co-culture with marine phototrophs has yet to be investigated. Following the observation of an antimicrobial activity against a range of phytoplankton by S. tropica, we here report that the photosynthate released by photosynthetic primary producers influences its biosynthetic capacities with production of cryptic molecules and the activation of orphan BGCs. Our work, using an approach combining metabolomics and proteomics, pioneers the use of phototrophs as a promising strategy to accelerate the discovery of novel natural products from marine actinobacteria.


Assuntos
Actinobacteria , Micromonosporaceae , Actinobacteria/genética , Micromonosporaceae/genética , Família Multigênica , Fitoplâncton
5.
Nat Prod Res ; 35(22): 4211-4217, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31729260

RESUMO

The actinomycete strain FIM06-0036 was isolated from marine sponge sample collected from the East China Sea and identified as Verrucosispora sp. based upon the results of 16S rRNA sequence analysis. One new alkaloid, 2-ethylhexyl 1H-imidazole-4-carboxylate (1), together with a known alkaloid butyl 1H-imidazole-4-carboxylate (2) was obtained from the fermentation products of this strain, the structures of compounds 1 and 2 were determined by their detailed analysis of 1 D, 2 D NMR and HR-ESI-MS data, along with literature data analysis. Compounds 1 and 2 were evaluated for their antimicrobial activity with MIC (minimum inhibitory concentration) values ranging from 8 to 256 µg · mL-1 against Helicobacter pylori, Klebsiella Pneumonia, Staphylococcus aureus and Enterococcus faecalis.


Assuntos
Alcaloides , Anti-Infecciosos , Micromonosporaceae , Alcaloides/farmacologia , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana , Micromonosporaceae/genética , RNA Ribossômico 16S/genética
6.
Molecules ; 25(21)2020 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-33138297

RESUMO

The appropriate regulation of T cell activity under inflammatory conditions is crucial for maintaining immune homeostasis. Salinosporamide A discovered as a self-resistance product from the marine bacterium Salinospora tropica, has been used as a potent proteasome inhibitor (PI). Although PIs have been developed as novel therapeutics for autoimmune diseases, due to their immunosuppressive effect, whether salinosporamide A inhibits T cell activation remains unknown. The current study finds that salinosporamide A is not cytotoxic, but controls T cell proliferation. Results from our cell cycle arrest analysis revealed that salinosporamide A leads to cell cycle arrest and regulates the expression of cyclin-dependent kinases. Under activated conditions, salinosporamide A abrogated T cell activation by T cell receptor-mediated stimulation, in which the production of cytokines was inhibited by pretreatment with salinosporamide A. Furthermore, we demonstrated that the regulation of T cell activation by salinosporamide A is mediated by suppressing the MAPK pathway. Therefore, our results suggest that salinosporamide A effectively suppresses T cell activation through regulating T cell proliferation and the cell cycle and provides great insight into the development of novel therapeutics for autoimmune diseases or graft-versus-host disease.


Assuntos
Organismos Aquáticos/química , Linfócitos T CD4-Positivos/metabolismo , Proliferação de Células/efeitos dos fármacos , Lactonas , Ativação Linfocitária/efeitos dos fármacos , Micromonosporaceae/química , Inibidores de Proteassoma , Pirróis , Animais , Humanos , Células Jurkat , Lactonas/química , Lactonas/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , Inibidores de Proteassoma/química , Inibidores de Proteassoma/farmacologia , Pirróis/química , Pirróis/farmacologia
7.
Mar Drugs ; 18(11)2020 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-33167356

RESUMO

A new cytotoxic thiodepsipeptide, verrucosamide (1), was isolated along with the known, related cyclic peptide thiocoraline, from the extract of a marine-derived actinomycete, a Verrucosispora sp., our strain CNX-026. The new peptide, which is composed of two rare seven-membered 1,4-thiazepane rings, was elucidated by a combination of spectral methods and the absolute configuration was determined by a single X-ray diffraction study. Verrucosamide (1) showed moderate cytotoxicity and selectivity in the NCI 60 cell line bioassay. The most susceptible cell lines were MDA-MB-468 breast carcinoma with an LD50 of 1.26 µM, and COLO 205 colon adenocarcinoma with an LD50 of 1.4 µM. Also isolated along with verrucosamide were three small 3-hydroxy(alkoxy)-quinaldic acid derivatives that appear to be products of the same biosynthetic pathway.


Assuntos
Antineoplásicos/farmacologia , Toxinas Marinhas/farmacologia , Micromonosporaceae/metabolismo , Neoplasias/tratamento farmacológico , Antineoplásicos/isolamento & purificação , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Toxinas Marinhas/isolamento & purificação , Estrutura Molecular , Neoplasias/patologia , Relação Estrutura-Atividade
8.
Arch Pharm Res ; 43(12): 1230-1258, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33237436

RESUMO

Actinomycetes are an important source for bioactive secondary metabolites. Among them, the genus Salinispora is one of the first salt obligatory marine species worldwide and is typically found in various types of substrates in tropical and subtropical marine environments including sediments and marine organisms. This genus produces a wide range of chemical scaffolds and bioactive compounds such as lomaiviticins, cyclomarins, rifamycins, salinaphthoquinones, and salinosporamides. This review arranged Salinispora derived secondary metabolites according to the three species that comprise the genus. Moreover, muta- and semi-synthesis analogs derived from salinosporamide were also described in this review.


Assuntos
Produtos Biológicos/farmacologia , Descoberta de Drogas , Micromonosporaceae/metabolismo , Animais , Produtos Biológicos/isolamento & purificação , Humanos , Estrutura Molecular , Metabolismo Secundário , Relação Estrutura-Atividade
9.
Appl Microbiol Biotechnol ; 104(21): 9283-9294, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32989516

RESUMO

Actinoplanes sp. SE50/110 is the industrially relevant producer of acarbose, which is used in the treatment of diabetes mellitus. Recent studies elucidated the expression dynamics in Actinoplanes sp. SE50/110 during growth. From these data, we obtained a large genomic region (ACSP50_3900 to ACSP50_3950) containing 51 genes, of which 39 are transcribed in the same manner. These co-regulated genes were found to be stronger transcribed on maltose compared with glucose as a carbon source. The transcriptional regulator MalT was identified as an activator of this maltose-regulated large genomic region (MRLGR). Since most of the genes are poorly annotated, the function of this region is farther unclear. However, comprehensive BLAST analyses indicate similarities to enzymes involved in amino acid metabolism. We determined a conserved binding motif of MalT overlapping the -35 promoter region of 17 transcription start sites inside the MRLGR. The corresponding sequence motif 5'-TCATCC-5nt-GGATGA-3' displays high similarities to reported MalT binding sites in Escherichia coli and Klebsiella pneumoniae, in which MalT is the activator of mal genes. A malT deletion and an overexpression mutant were constructed. Differential transcriptome analyses revealed an activating effect of MalT on 40 of the 51 genes. Surprisingly, no gene of the maltose metabolism is affected. In contrast to many other bacteria, MalT is not the activator of mal genes in Actinoplanes sp. SE50/110. Finally, the MRLGR was found partly in other closely related bacteria of the family Micromonosporaceae. Even the conserved MalT binding site was found upstream of several genes inside of the corresponding regions. KEY POINTS : • MalT is the maltose-dependent activator of a large genomic region in ACSP50_WT. • The consensus binding motif is similar to MalT binding sites in other bacteria. • MalT is not the regulator of genes involved in maltose metabolism in ACSP50_WT.


Assuntos
Actinoplanes , Micromonosporaceae , Acarbose , Proteínas de Bactérias/genética , Genômica , Maltose , Micromonosporaceae/genética
10.
Mol Genet Genomics ; 295(6): 1529-1535, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32894358

RESUMO

Lanthipeptides are a subgroup of ribosomally encoded and post-translationally modified peptides (RiPPs) which frequently possess potent biological activity. Here we provide the first comprehensive bioinformatic analysis of the lanthipeptide-producing capability of the Salinispora genus, a marine actinomycete. One hundred twenty-two Salinispora arenicola, tropica, and pacifica genomic sequences were analyzed for lanthipeptide gene clusters, and the resulting 182 clusters were divided into seven groups based on sequence similarities. Group boundaries were defined based on LanB and LanM sequences with greater than 80% similarity within groups. Of the seven groups, six are predicted to encode class I lanthipeptides while only one group is predicted to encode class II lanthipeptides. Leader and core peptides were predicted for each cluster along with the number of possible lanthionine bridges. Notably, all of the predicted products of these clusters would represent novel lanthipeptide scaffolds. Of the 122 Salinispora genomes analyzed in this study, 92% contained at least one lanthipeptide gene cluster suggesting that Salinispora is a rich, yet untapped, source of lanthipeptides.


Assuntos
Alanina/análogos & derivados , Proteínas de Bactérias/metabolismo , Genoma Bacteriano , Micromonosporaceae/metabolismo , Fragmentos de Peptídeos/metabolismo , Sulfetos/metabolismo , Alanina/isolamento & purificação , Alanina/metabolismo , Proteínas de Bactérias/genética , Genômica , Micromonosporaceae/genética , Micromonosporaceae/crescimento & desenvolvimento , Fragmentos de Peptídeos/isolamento & purificação , Sulfetos/isolamento & purificação
11.
Chembiochem ; 21(24): 3495-3499, 2020 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-32776704

RESUMO

Homochirality is a signature of biological systems. The essential and ubiquitous cofactor S-adenosyl-l-methionine (SAM) is synthesized in cells from adenosine triphosphate and l-methionine to yield exclusively the (S,S)-SAM diastereomer. (S,S)-SAM plays a crucial role as the primary methyl donor in transmethylation reactions important to the development and homeostasis of all organisms from bacteria to humans. However, (S,S)-SAM slowly racemizes at the sulfonium center to yield the inactive (R,S)-SAM, which can inhibit methyltransferases. Control of SAM homochirality has been shown to involve homocysteine S-methyltransferases in plants, insects, worms, yeast, and in ∼18 % of bacteria. Herein, we show that a recombinant protein containing a domain of unknown function (DUF62) from the actinomycete bacterium Salinispora tropica functions as a stereoselective (R,S)-SAM hydrolase (adenosine-forming). DUF62 proteins are encoded in the genomes of 21 % of bacteria and 42 % of archaea and potentially represent a novel mechanism to remediate SAM damage.


Assuntos
Hidrolases/metabolismo , S-Adenosilmetionina/metabolismo , Hidrolases/química , Micromonosporaceae/enzimologia , Estrutura Molecular , S-Adenosilmetionina/química , Estereoisomerismo
12.
Int J Syst Evol Microbiol ; 70(8): 4668-4682, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32701422

RESUMO

Ten representative actinobacterial strains isolated from marine sediments collected worldwide were studied to determine their taxonomic status. The strains were previously identified as members of the genus Salinispora and shared >99 % 16S rRNA gene sequence similarity to the three currently recognized Salinispora species. Comparative genomic analyses resulted in the delineation of six new species based on average nucleotide identity and digital DNA-DNA hybridization values below 95 and 70 %, respectively. The species status of the six new groups was supported by a core-genome phylogeny reconstructed from 2106 orthologs detected in 118 publicly available Salinispora genomes. Chemotaxonomic and physiological studies were used to complete the phenotypic characterization of the strains. The fatty acid profiles contained the major components iso-C16 : 0, C15 : 0, iso-17 : 0 and anteiso C17 : 0. Galactose and xylose were common in all whole-sugar patterns but differences were found between the six groups of strains. Polar lipid compositions were also unique for each species. Distinguishable physiological and biochemical characteristics were also recorded. The names proposed are Salinispora cortesiana sp. nov., CNY-202T (=DSM 108615T=CECT 9739T); Salinispora fenicalii sp. nov., CNT-569T (=DSM 108614T=CECT 9740T); Salinispora goodfellowii sp. nov., CNY-666T (=DSM 108616T=CECT 9738T); Salinispora mooreana sp. nov., CNT-150T (=DSM 45549T=CECT 9741T); Salinispora oceanensis sp. nov., CNT-138T (=DSM 45547T=CECT 9742T); and Salinispora vitiensis sp. nov., CNT-148T (=DSM 45548T=CECT 9743T).


Assuntos
Sedimentos Geológicos/microbiologia , Micromonosporaceae/classificação , Filogenia , Água do Mar/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
13.
Int J Syst Evol Microbiol ; 70(5): 3309-3315, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32375928

RESUMO

A novel actinobacterium, designated strain H14505T, was isolated from a soil sample collected in Hong Yuan, Sichuan, southwest PR China. The temperature, pH and NaCl ranges for growth were determined to be 15-35 °C (optimum, 28 °C), 6.0-8.0 (optimum, pH 7.0) and 0-2 % (w/v; optimum without NaCl), respectively. The polar lipdis detected for strain H14505T were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol, glycolipid and four unidentified lipids. The predominant menaquinones of strain H14505T were MK-9(H4) and MK-9(H6), and the prevalent fatty acids (>10 %) were C18 : 1 ω9c, C17 : 1 ω8c, summed feature 5 (anteiso-C18 : 0/ C18 : 2 ω6,9c) and C16 : 0. Phylogenetic analysis based on 16S rRNA gene and whole-genome sequences indicated that strain H14505T showed high similarity to Catellatospora vulcania NEAU-JM1T (99.0 %) and Catellatospora paridis NEAU-CL2T (99.0 %), and formed a monophyletic clade within the the genus Catellatospora in the phylogenetic trees. However, the average nucleotide indentity and DNA-DNA hybridization values between strain H14505T and closely related Catellatospora species showed that it belonged to a distinct species. Furthermore, the results of morphological, physiological and biochemical tests allowed further phenotypic differentiation of strain H14505T from its closest relatives. Thus, it is proposed that strain H14505T represents a novel species of the genus Catellatospora, for which the name Catellatospora sichuanensis sp. nov. is proposed. The type strain of Catellatospora sichuanensis is H14505T (=JCM 32394T=CICC 11042T).


Assuntos
Micromonosporaceae/classificação , Filogenia , Microbiologia do Solo , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Micromonosporaceae/isolamento & purificação , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
14.
J Nat Prod ; 83(4): 1152-1156, 2020 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-32191465

RESUMO

Overexpression of phosphopantetheinyl transferase (PPtase)-encoding genes sfp and svp in the marine-derived Verrucosispora sp. SCSIO 40062 led to the production of two new aminofuran monomers, proximicin F (1) and proximicin G (3) and a new dimer diproximicin A (2), along with two known compounds, proximicins B (4) and C (5). Their structures were unambiguously elucidated on the basis of detailed NMR spectroscopic analysis and high-resolution electrospray ionization mass spectrometry (HRESIMS) data. Proximicin B (4) showed moderate antibacterial activities against Staphylococcus aureus, methicillin-resistant S. aureus, and Bacillus subtilis.


Assuntos
Antibacterianos/farmacologia , Bacillus subtilis/química , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Micromonosporaceae/química , Netropsina/análogos & derivados , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/química , Antibacterianos/isolamento & purificação , Staphylococcus aureus Resistente à Meticilina/química , Testes de Sensibilidade Microbiana , Estrutura Molecular , Netropsina/química , Netropsina/farmacologia , Espectrometria de Massas por Ionização por Electrospray , Staphylococcus aureus/química
15.
Chembiochem ; 21(11): 1629-1632, 2020 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-31957947

RESUMO

Five new members of the salinilactone family, salinilactones D-H, are reported. These bicyclic lactones are produced by Salinispora bacteria and display extended or shortened alkyl side chains relative to the recently reported salinilactones A-C. They were identified by GC/MS, gas chromatographic retention index, and comparison with synthetic samples. We further investigated the occurrence of salinilactones across six newly proposed Salinispora species to gain insight into how compound production varies among taxa. The growth-inhibiting effect of this compound family on multiple biological systems including non-Salinispora actinomycetes was analyzed. Additionally, we found strong evidence for significant cytotoxicity of the title compounds.


Assuntos
Actinobacteria/química , Organismos Aquáticos/química , Produtos Biológicos/farmacologia , Lactonas/farmacologia , Micromonosporaceae/química , Actinobacteria/metabolismo , Actinoplanes/efeitos dos fármacos , Actinoplanes/crescimento & desenvolvimento , Organismos Aquáticos/metabolismo , Produtos Biológicos/química , Produtos Biológicos/classificação , Produtos Biológicos/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas , Lactonas/química , Lactonas/classificação , Lactonas/isolamento & purificação , Testes de Sensibilidade Microbiana , Micromonospora/efeitos dos fármacos , Micromonospora/crescimento & desenvolvimento , Micromonosporaceae/efeitos dos fármacos , Micromonosporaceae/crescimento & desenvolvimento , Micromonosporaceae/metabolismo , Estrutura Molecular
16.
Molecules ; 25(3)2020 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-31991684

RESUMO

Pilidiella granati, also known as Coniella granati, is the etiological agent of pomegranate fruit dry rot. This fungal pathogen is also well-known as responsible for both plant collar rot and leaf spot. Because of its aggressiveness and the worldwide diffusion of pomegranate crops, the selection of cultivars less susceptible to this pathogen might represent an interesting preventive control measure. In the present investigation, the role of polyphenols in the susceptibility to P. granati of the two royalties-free pomegranate cultivars Wonderful and Mollar de Elche was compared. Pomegranate fruit were artificially inoculated and lesion diameters were monitored. Furthermore, pathogen DNA was quantified at 12-72 h post-inoculation within fruit rind by a real time PCR assay setup herein, and host total RNA was used in expression assays of genes involved in host-pathogen interaction. Similarly, protein extracts were employed to assess the specific activity of enzymes implicated in defense mechanisms. Pomegranate phenolic compounds were evaluated by HPLC-ESI-MS and MS2. All these data highlighted 'Wonderful' as less susceptible to P. granati than 'Mollar de Elche'. In the first cultivar, the fungal growth seemed controlled by the activation of the phenylpropanoid pathway, the production of ROS, and the alteration of fungal cell wall. Furthermore, antifungal compounds seemed to accumulate in 'Wonderful' fruit following inoculation. These data suggest that pomegranate polyphenols have a protective effect against P. granati infection and their content might represent a relevant parameter in the selection of the most suitable cultivars to reduce the economic losses caused by this pathogen.


Assuntos
Resistência à Doença , Micromonosporaceae/crescimento & desenvolvimento , Doenças das Plantas/microbiologia , Polifenóis/metabolismo , Romã (Fruta) , Frutas/metabolismo , Frutas/microbiologia , Romã (Fruta)/metabolismo , Romã (Fruta)/microbiologia
17.
Appl Microbiol Biotechnol ; 104(4): 1533-1543, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31894364

RESUMO

Marine microorganisms live in dramatically different environments and have attracted much attention for their structurally unique natural products with potential strong biological activity. Based on the one strain-many compounds (OSMAC) strategy and liquid chromatography mass spectrometry (LC-MS) methods, our continuing efforts on the investigation of novel active compounds from marine Verrucosispora sp. MS100137 has led to the identification of a new polycyclic metabolite, abyssomicin Y (1), together with six known abyssomicin and proximicin analogs (2-7). Abyssomicin Y is a type I abyssomicin with an epoxide group at C-8 and C-9. Compounds 1-3 showed potent inhibitory effects against the influenza A virus; their observed inhibition rates were 97.9%, 98.3%, and 95.9%, respectively, at a concentration of 10 µM, and they displayed lower cytotoxicity than 4. The structures were determined by different NMR techniques and HRMS experiments. This investigation revealed that OSMAC could serve as a useful method for enabling the activation of the silent genes in the microorganism and for the formation of previously unreported active secondary metabolites.


Assuntos
Antivirais/farmacologia , Organismos Aquáticos/química , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Vírus da Influenza A/efeitos dos fármacos , Micromonosporaceae/química , Células A549 , Antivirais/isolamento & purificação , Produtos Biológicos/isolamento & purificação , Produtos Biológicos/farmacologia , Compostos Bicíclicos Heterocíclicos com Pontes/isolamento & purificação , Cromatografia Líquida , Humanos , Espectrometria de Massas , Metabolismo Secundário
18.
Nat Prod Res ; 34(21): 3082-3088, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31075998

RESUMO

Using the draft genome sequence of Verrucosispora sp. FIM060022, we have identified a new desferrioxamine-like siderophore, FW0622. This is the first chemically characterized siderophore obtained from Verrucosispora. The structure was elucidated by extensive spectral analyses. The biosynthetic pathway of FW0622 was proposed to occur via the non-ribosomal peptide synthetase (NRPS)-independent (NIS) synthetase pathway based on the putative biosynthetic siderophore gene cluster in FIM060022. The results demonstrate that marine-derived Verrucosispora species deserve recognition as an important source of new natural products. Furthermore, this study verified that genome mining is an effective way to identify compounds that may be overlooked by traditional methods.


Assuntos
Anti-Infecciosos/farmacologia , Micromonosporaceae/genética , Sideróforos/química , Sideróforos/metabolismo , Anti-Infecciosos/química , Vias Biossintéticas , Genoma Bacteriano , Genômica , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Micromonosporaceae/metabolismo , Estrutura Molecular , Família Multigênica , Peptídeo Sintases/genética , Peptídeo Sintases/metabolismo , Metabolismo Secundário/genética , Sideróforos/genética , Sideróforos/farmacologia
19.
Pol J Microbiol ; 69(3): 321-330, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33574861

RESUMO

Marine obligate actinobacteria produce a wide variety of secondary metabolites with biological activity, notably those with antibiotic activity urgently needed against multi-drug-resistant bacteria. Seventy-five marine actinobacteria were isolated from a marine sediment sample collected in Punta Arena de La Ventana, Baja California Sur, Mexico. The 16S rRNA gene identification, Multi Locus Sequence Analysis, and the marine salt requirement for growth assigned seventy-one isolates as members of the genus Salinispora, grouped apart but related to the main Salinispora arenicola species clade. The ability of salinisporae to inhibit bacterial growth of Staphylococcus epidermidis, Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacer baumannii, Pseudomonas aeruginosa, and Enterobacter spp. was evaluated by cross-streaking plate and supernatant inhibition tests. Ten supernatants inhibited the growth of eight strains of S. epidermidis from patients suffering from ocular infections, two out of the eight showed growth inhibition on ten S. epidermidis strains from prosthetic joint infections. Also, it inhibited the growth of the remaining six multi-drug-resistant bacteria tested. These results showed that some Salinispora strains could produce antibacterial compounds to combat bacteria of clinical importance and prove that studying different geographical sites uncovers untapped microorganisms with metabolic potential.


Assuntos
Bactérias/crescimento & desenvolvimento , Farmacorresistência Bacteriana Múltipla , Sedimentos Geológicos/microbiologia , Micromonosporaceae/fisiologia , Actinobacteria/classificação , Actinobacteria/genética , Actinobacteria/isolamento & purificação , Actinobacteria/fisiologia , Antibacterianos/farmacologia , Antibiose , Bactérias/efeitos dos fármacos , Bactérias/patogenicidade , Proteínas de Bactérias/genética , Meios de Cultivo Condicionados/farmacologia , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Humanos , México , Micromonosporaceae/classificação , Micromonosporaceae/genética , Micromonosporaceae/isolamento & purificação , Filogenia , RNA Ribossômico 16S/genética , Água do Mar/microbiologia
20.
Int. microbiol ; 22(4): 521-530, dic. 2019. mapas, graf, tab
Artigo em Inglês | IBECS | ID: ibc-185070

RESUMO

A total of 168 actinomycete colonies were isolated from 14 sediment samples of the northern parts of the Oman Sea and were screened for cytotoxic and antimicrobial activity. Among four media and two treatments, the glucose arginine agar medium (18%) and heat treatment (28.3%) showed maximum isolation rate of actinomycetes. Preliminary characterization revealed that the members of Streptomycetaceae were widely distributed (66%) in the most of the sampling stations followed by Micromonosporaceae (14%), Nocardiaceae (6%), and Pseudonocardiaceae (4%), respectively. Approximately, 23.8% of the isolates inhibited the growth of at least one of the microbial test strains, while the majority of them belonged to the Streptomycetaceae family. Minimum inhibitory concentrations of the ethyl acetate culture extracts of the five most putative isolates varied from 64 μg/mL against Micrococcus luteus and Candida albicans to 1 mg/mL against Aspergillus niger. These extracts showed significant cytotoxic activity at18.74-193.5 μg/mL on the human breast (MCF7), colon (HCT 116), and liver (HepG2) tumor cell lines while exhibited less or no cytotoxicity on the normal cell line (HUVEC). Interestingly, IFSRI 193 extract selectively inhibited the growth of HCT 116 cell line and gram-positive bacteria. 16S rRNA gene sequencing revealed that the potent isolates have 97 to 99% similarity with S. chartreusis, S. cacaoi, S. sampsonii, S. qinglanensis, and S. diastaticus. These results suggested that the five Streptomyces strains could be considered candidates for discovering the antitumor antibiotics


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Assuntos
Infecções por Actinomycetales/microbiologia , Sedimentos Marinhos (Saúde Ambiental)/análise , Streptomycetaceae/isolamento & purificação , Micromonosporaceae/isolamento & purificação , Nocardiaceae/isolamento & purificação , RNA Ribossômico 16S/isolamento & purificação , Células HCT116/metabolismo , Células HCT116/microbiologia
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