Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 64
Filtrar
Mais filtros










Tipo de estudo
Intervalo de ano de publicação
1.
Anal Bioanal Chem ; 2020 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-31919609

RESUMO

In recent years, use of supercritical-fluid chromatography (SFC) with CO2 as the mobile phase has been expanding in the research laboratory and industry since it is considered to be a green analytical method. This technique offers numerous advantages, such as good separation and sensitive detection, short analysis times, and stability of analytes. In this study, a method for quantification of N-acyl homoserine lactones (AHLs), signaling molecules responsible for cell-to-cell communication initially discovered in bacteria, by SFC coupled with high-resolution mass spectrometry (HRMS) was developed. The SFC conditions and MS ionization settings were optimized to obtain the best separation and greatest sensitivity. The optimal analysis conditions allowed quantification of up to 30 AHLs in a single run within 16 min with excellent linearity (R2 > 0.998) and sensitivity (picogram level). This method was then applied to study AHL production by one Gram-negative endophytic bacterium, Paraburkholderia sp. BSNB-0670. Nineteen known AHLs were detected, and nine abundant HSLs were quantified. To further investigate the production of uncommon AHLs, a molecular networking approach was applied on the basis of the SFC-HRMS/MS data. This led to additional identification of four unknown AHLs annotated as N-3-hydroxydodecanoylol homoserine lactone, N-3-hydroxydodecadienoyl homoserine lactone, and N-3-oxododecenoyl homoserine lactones (two isomers).

2.
Sci Rep ; 9(1): 8729, 2019 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-31217530

RESUMO

Mankind is on the verge of a postantibiotic era. New concepts are needed in our battle to attenuate infectious diseases around the world and broad spectrum plant-inspired synergistic pharmaceutical preparations should find their place in the global fight against pathogenic microorganisms. To progress towards the discovery of potent antifungal agents against human pathologies, we embarked upon developing chemometric approach coupled with statistical design to unravel the origin of the anticandidal potential of a set of 66 essential oils (EOs). EOs were analyzed by GC-MS and tested against Candida albicans and C. parapsilosis (Minimal Inhibitory Concentration, MIC). An Orthogonal Partial Least Square (OPLS) analysis allowed us to identify six molecules presumably responsible for the anticandidal activity of the oils: (Z)-ligustilide, eugenol, eugenyl acetate, citral, thymol, and ß-citronellol. These compounds were combined following a full factorial experimental design approach in order to optimize the anticandidal activity and selectivity index (SI = IC50(MRC5 cells)/MIC) through reconstituted mixtures. (Z)-Ligustilide and citral were the most active compounds, while (Z)-ligustilide and eugenol were the two main factors that most contributed to the increase of the SI. These two terpenes can, therefore, be used to construct bioinspired synergistic anticandidal mixtures.

3.
Nat Prod Res ; : 1-4, 2019 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-31180242

RESUMO

A new trace alkaloid possessing the lignan structure, named oleraisoindole A, was obtained from the extract of the Portulaca oleracea L.. The structure of oleraisoindole A was elucidated by 1D and 2D NMR and high resolution electrospray ionization time-of-flight mass spectroscopic methods. The compound presented an anticholinesterase effect with the IC50 value of 60.4 µM.

4.
Int J Mol Sci ; 20(8)2019 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-31022840

RESUMO

A library of 197 endophytic fungi and bacteria isolated from the Amazonian palm tree Astrocaryum sciophilum was extracted and screened for antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA). Four out of five antibacterial ethyl acetate extracts were also cytotoxic for the MRC-5 cells line. Liquid chromatography coupled to tandem mass spectrometry (UPHLC-HRMS/MS) analyses combined with molecular networking data processing were carried out to allow the identification of depsipeptides and cyclopeptides responsible for the cytotoxicity in the dataset. Specific ion clusters from the active Luteibacter sp. extract were also highlighted using an MRSA activity filter. A chemical study of Luteibacter sp. was conducted leading to the structural characterization of eight fatty acid exhibiting antimicrobial activity against MRSA in the tens of µg/mL range.


Assuntos
Antibacterianos/química , Arecaceae/microbiologia , Endófitos/química , Gammaproteobacteria/química , Lipídeos/química , Antibacterianos/farmacologia , Cromatografia Líquida de Alta Pressão , Depsipeptídeos/química , Depsipeptídeos/farmacologia , Ácidos Graxos/química , Ácidos Graxos/farmacologia , Humanos , Lipídeos/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Modelos Moleculares , Infecções Estafilocócicas/tratamento farmacológico , Espectrometria de Massas em Tandem , Árvores/microbiologia
5.
Int J Mol Sci ; 20(5)2019 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-30818755

RESUMO

Origanum ehrenbergii Boiss., an endemic plant to Lebanon, is widely acknowledged in Lebanese traditional medicine. The aim of the present study was to evaluate the influence of the drying method, region, and time of harvest on yield and chemical composition of O. ehrenbergii essential oils (EOs). Plants were harvested monthly throughout 2013 and 2014, from two different regions, Aabadiye and Qartaba, then dried using two drying methods: lyophilization and shade-drying at 4 °C. EO was extracted by hydrodistillation and analyzed by GC/MS. GC-MS data, combined with independent component analysis (ICA) and common component and specific weight analysis (CCSWA), showed that drying techniques, region of harvest, and soil composition have no effect on the chemical composition of O. ehrenbergii EOs. Of the factors analyzed, only harvesting time affected the EO composition of this species. High and stable amounts of carvacrol, associated with reliable antimicrobial activities, were detected in material harvested between March and October. EOs obtained from plants harvested in Aabadiye in January and February showed high amounts of thymoquinone, related to anti-inflammatory and cytotoxic effects. The use of ICA and CCSWA was proven to be efficient, and allowed the development of a discriminant model for the classification of O. ehrenbergii chemotype and the determination of the best harvesting time.


Assuntos
Óleos Voláteis/análise , Óleos Voláteis/química , Origanum/química , Altitude , Dessecação , Análise Discriminante , Geografia , Líbano , Análise de Componente Principal , Solo , Fatores de Tempo
6.
Int J Mol Sci ; 20(5)2019 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-30832353

RESUMO

A biological evaluation of a library of extracts from entomopathogen strains showed that Pantoea sp. extract has significant antimicrobial and insecticidal activities. Three hydroxyacyl-phenylalanine derivatives were isolated from this strain. Their structures were elucidated by a comprehensive analysis of their NMR and MS spectroscopic data. The antimicrobial and insecticidal potencies of these compounds were evaluated, and compound 3 showed 67% mortality against Aedes aegypti larvae at a concentration of 100 ppm, and a minimum inhibitory concentration (MIC) of 16 µg/mL against methicillin-resistant Staphylococcus aureus. Subsequently, hydroxyacyl-phenylalanine analogues were synthesized to better understand the structure-activity relationships within this class of compounds. Bioassays highlighted the antimicrobial potential of analogues containing saturated medium-chain fatty acids (12 or 14 carbons), whereas an unsaturated long-chain fatty acid (16 carbons) imparted larvicidal activity. Finally, using a molecular networking-based approach, several close analogues of the isolated and newly synthesized lipoamino acids were discovered in the Pantoea sp. extract.


Assuntos
Anti-Infecciosos/química , Ácidos Graxos/química , Inseticidas/química , Pantoea/química , Aedes/efeitos dos fármacos , Animais , Anti-Infecciosos/síntese química , Anti-Infecciosos/farmacologia , Ácidos Graxos/síntese química , Ácidos Graxos/farmacologia , Inseticidas/síntese química , Inseticidas/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Relação Estrutura-Atividade
7.
Microbes Environ ; 34(1): 99-103, 2019 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-30760664

RESUMO

Vibrio fischeri possesses a complex AHL-mediated Quorum-sensing (QS) system including two pathways, LuxI/R (3-oxo-C6-HSL and C6-HSL) and AinS/R (C8-HSL), which are important for the regulation of physiological traits. Diverse QS-dependent functional phenotypes have been described in V. fischeri; however, AHL diversity is still underestimated. In the present study, we investigated AHL diversity in five symbiotic V. fischeri strains with distinct phenotypic properties using UHPLC-HRMS/MS. The results obtained (1) revealed an unexpectedly high diversity of signaling molecules, (2) emphasized the complexity of QS in V. fischeri, and (3) highlight the importance of understanding the specificity of AHL-mediated QS.


Assuntos
Acil-Butirolactonas/química , Aliivibrio fischeri/química , Decapodiformes/microbiologia , Percepção de Quorum , Acil-Butirolactonas/metabolismo , Aliivibrio fischeri/genética , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica , Variação Genética , Fenótipo , Especificidade da Espécie , Simbiose
8.
Fitoterapia ; 133: 130-136, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30654130

RESUMO

With the goal of unravelling antimicrobial agents and mixtures inspired by plant defences, we investigated the antibacterial and antifungal efficacy of Hirtellina lobelii DC. essential oil (EO), both alone and in combination with antimicrobial drugs. Hirtellina lobelii DC. EO was analysed by GC, GC-MS and partial fractionation/NMR. It was essentially composed of oxygenated sesquiterpenes (75.2%), with α-bisabolol (34.5%), fokienol (12.0%) and T-muurolol (6.8%) serving as the main components. Microbial susceptibility was determined by the broth microdilution method and was expressed as minimum inhibitory concentration (MIC) and minimum bactericidal or fungicidal concentration (MBC or MFC). This EO was found to possess remarkable bactericidal (MBC/MIC = 2) and fungicidal (MFC/MIC = 1-4) potential, particularly against the Gram (+) bacteria Staphylococcus aureus, including its methicillin-resistant forms, the yeast Cryptococcus neoformans and dermatophytes from the genus Trichophyton (MICs 8-128 µg/ml). The examination of the combined effects of the EO with antimicrobial drugs revealed synergisms of the EO with vancomycin against S. aureus and of the EO with fluconazole and griseofulvin against dermatophytic fungi (FICI 0.2-0.5). The effect of H. lobelii EO on the morphologies of fungal hyphae and bacteria, as determined by scanning electronic microscopy (SEM), showed fungal hyphae swelling and bulging. These results suggest that H. lobelii EO and its major constituent, α-bisabolol, have remarkable antimicrobial potential. Combination therapies of this EO with antifungal drugs could offer a promising alternative for treatment of human mycoses caused by filamentous dermatophytic fungi.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Asteraceae/química , Óleos Voláteis/farmacologia , Sesquiterpenos/farmacologia , Sinergismo Farmacológico , Líbano , Testes de Sensibilidade Microbiana , Estrutura Molecular , Compostos Fitoquímicos/farmacologia , Componentes Aéreos da Planta/química
9.
Biodegradation ; 30(4): 287-300, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30600423

RESUMO

The bacterial strain F4, isolated from olive oil-contaminated soil, has been found to produce biosurfactants as confirmed by oil displacement test and the emulsification index results. The identification of the strain F4, by 16S ribosomal RNA gene, showed a close similarity to Bacillus safensis, therefore the strain has been termed Bacillus safensis F4. The Thin Layer Chromatography (TLC) and the High Pressure Liquid Chromatography-Mass Spectrometry (HPLC-MS/MS) demonstrated that the biosurfactant had a lipopeptide structure and was classified as surfactin. The present study showed also that the produced biosurfactant has an important antibacterial activity against several pathogen strains as monitored with minimum inhibitory concentration (MIC) micro-assays. In particular, it presented an interesting anti-planktonic activity with a MIC of 6.25 mg mL-1 and anti-adhesive activity which exceeded 80% against the biofilm-forming Staphylococcus epidermidis S61 strain. Moreover, the produced lipopeptide showed an antitumor activity against T47D breast cancer cells and B16F10 mouse melanoma cells with IC50 of 0.66 mg mL-1 and 1.17 mg mL-1, respectively. Thus, our results demonstrated that Bacillus safensis F4 biosurfactant exhibited a polyvalent activity via a considerable antibiofilm and antitumoral potencies.


Assuntos
Bacillus , Animais , Antibacterianos , Biodegradação Ambiental , Camundongos , Tensoativos , Espectrometria de Massas em Tandem
10.
Nat Prod Res ; 33(18): 2583-2590, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29665731

RESUMO

A new alkaloid, (10E, 12E)-9-ureidooctadeca-10, 12-dienoic acid, named oleraurea (1) and 10 known compounds, p-hydroxybenzaldehyde (2), p-hydroxybenzoic acid (3), p-hydroxyacetophenone (4), benzamide (5), (E)-p-coumaramide (6), (E)-ferulamide (7), soyalkaloid A (8), ß-carboline-3-carboxylic acid (9), 2, 3, 4, 9-tetrahydro-1H-pyrido [3, 4-b] indole-3-carboxylic acid (10), (1S, 3S)-1-methyl-1, 2, 3, 4-tetrahydro-ß-carboline-3-carboxylic acid (11) were obtained from Portulaca oleracea L., in which, compounds 4, 5, 8-11 were isolated from the plant for the first time. The structure of the compound 1 was identified using spectroscopic methods including 1D and 2D NMR, HR-ESI-TOF-MS. The compounds 1, 5-11 presented anticholinesterase activities, but the P. oleracea extract (POE) presented very low anticholinesterase activity.


Assuntos
Alcaloides/farmacologia , Inibidores da Colinesterase/farmacologia , Portulaca/química , Ureia/análogos & derivados , Ureia/farmacologia , Alcaloides/química , Inibidores da Colinesterase/química , Avaliação Pré-Clínica de Medicamentos/métodos , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Extratos Vegetais/química , Espectrometria de Massas por Ionização por Electrospray , Ureia/química
11.
Anal Chem ; 91(1): 990-995, 2019 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-30516955

RESUMO

Octocrylene (OC) is an ingredient used in many sunscreens and cosmetics worldwide. Our group evaluated the toxicity of OC in corals. Adult Pocillopora damicornis coral was treated with OC at concentrations of 5, 50, 300, and 1000 µg/L. Most polyps were closed at concentrations of 300 µg/L and higher. Further, metabolomic profiling provided crucial information regarding OC accumulation in coral tissues and OC toxicity. First, we demonstrated that OC was transformed into fatty acid conjugates via oxidation of the ethylhexyl chain, yielding very lipophilic OC analogues that accumulate in coral tissues. Second, the differential analysis of coral profiles revealed higher levels of 15 acylcarnitines, suggesting abnormal fatty acid metabolism related to mitochondrial dysfunction. The formation of OC analogues suggests that OC concentrations measured in the environment, and organisms may have been largely underestimated. Overall, these results call for an in-depth evaluation of OC toxicity and the reevaluation of the actual OC accumulation rate in the ocean's food chain, including OC-fatty acid conjugates.

12.
Nat Prod Res ; : 1-7, 2018 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-30580585

RESUMO

A new lignan, named oleralignan (1) and three known componds (+)-syringaresinol (2), (+)-lirioresinol A (3) and monomethyl 3,3',4,4'-tetrahydroxy-δ-truxinate (4) were isolated from the P. oleracea for the first time. The compound (1) were identified by 1D, 2D NMR spectroscopic methods and high resolution electrospray ionization time-of-flight mass spectrometry. In addition, it was found that the four lignans presented the scavenging activities in 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical quenching assay more than that of hydroxyl anisole (BHA). [Figure: see text].

14.
J Chromatogr B Analyt Technol Biomed Life Sci ; 1100-1101: 100-105, 2018 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-30300864

RESUMO

Glycation is a common non-enzymatic reaction between proteins and sugars, which gives rise in the human body to the formation of advanced glycation end products (AGEs). These modifications impacts both extra and intracellular proteins, leading to cells and tissues dysfunctions. In the skin, accumulation of AGEs leads to aesthetic consequences, wrinkles, dark spots and yellowish skin tone, as it can be seen in diabetic patients. Consequently, there is a growing dermatological interest to find compounds able to eliminate AGEs accumulated in skin. In this context, a method has been developed to detect and quantify intracellular glycation in human dermal fibroblasts. After cultivation of fibroblasts, cell lysates were injected in an HPLC system coupled with a fluorescence detector in by-pass mode. The system allows the simultaneous measurement of global AGEs and particular pentosidine amounts using two sets of wavelengths in a single run of 1 min. The immunocytochemistry approach was used to valid the HPLC analysis data. The method developed was able to quantify changes in global AGEs and pentosidine content in cells in response to glyoxal treatment. Fibroblasts treated with 500 µM of glyoxal for 48 h showed a significant 2.3-fold and 2.6-fold increase in the content of AGEs and pentosidine respectively compared to control cells. As an application, a screening of natural extracts have been done and the method allowed identifying extracts able to significantly reduce the amount of pentosidine in fibroblasts (-32%). These extracts act as deglycation agents of interest in the field of dermatology and cosmetology.


Assuntos
Cromatografia Líquida/métodos , Fibroblastos/citologia , Produtos Finais de Glicação Avançada/análise , Microscopia de Fluorescência/métodos , Pele/citologia , Extratos Celulares/química , Células Cultivadas , Feminino , Glicosilação , Humanos , Pessoa de Meia-Idade , Reprodutibilidade dos Testes
15.
Org Lett ; 20(13): 3780-3783, 2018 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-29923409

RESUMO

The newly discovered macrolactone, mucorolactone, along with eight known compounds, was isolated from an ethyl acetate extract of the insect-borne fungus Mucor sp. All structures were elucidated using 1D and 2D NMR and MS spectroscopic experiments. Relative and absolute configurations of the original skeleton of mucorolactone was deduced from NOESY experiments, from the 13C NMR chemical shift calculation based on the DP4 probability method, and from the comparison of experimental and calculated electronic circular dichroism spectra.


Assuntos
Mucor , Dicroísmo Circular , Espectroscopia de Ressonância Magnética , Estrutura Molecular
16.
Phytochemistry ; 151: 69-77, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29674105

RESUMO

The fungus Neonectria discophora SNB-CN63 has been isolated from the nest of the termite Nasutitermes corniger found in French Guiana. From the ethyl acetate extract of fungal culture, bioassay guided fractionation led to the isolation of fourteen ilicicolinic acids and ilicicolinal derivatives. Their structures were elucidated by analyses of 1D and 2D NMR and MS spectroscopic data. All metabolites were tested against several microbial pathogens and six displayed antimicrobial activities with MIC <16 µg/mL on T. rubrum, Staphylococcus aureus and methicillin-resistant S. aureus. Based on their structural similarities, a common biosynthetic pathway is proposed for all isolated metabolites.


Assuntos
Antibacterianos/farmacologia , Benzoatos/farmacologia , Benzofuranos/farmacologia , Hypocreales/química , Antibacterianos/química , Antibacterianos/isolamento & purificação , Benzoatos/química , Benzoatos/isolamento & purificação , Benzofuranos/química , Benzofuranos/isolamento & purificação , Relação Dose-Resposta a Droga , Testes de Sensibilidade Microbiana , Conformação Molecular , Staphylococcus aureus/efeitos dos fármacos , Relação Estrutura-Atividade , Trichophyton/efeitos dos fármacos
17.
Fitoterapia ; 127: 257-262, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29501925

RESUMO

Three new compounds, identified as (3S)-5-hydroxy-3-(2-hydroxybenzyl)-7-methoxychroman-4-one, oleracone C (1), 5-hydroxy-3-(2-hydroxybenzyl)-7-methoxy-4H-chromen-4-one, oleracone D (2), and 1-(2-hydroxy-4,6-dimethoxyphenyl)-3-(2-hydroxyphenyl)propan-1-one, oleracone E (4), together with one new natural product, 5,7-dimethoxy-4-O-2'-cycloflavan (3) already known from synthesis, and two known compounds, (2S)-5,2'-dihydroxy-7-methoxyflavanone (5) and 2',4'-dihydroxy-4,6'-dimethoxychalcone (6) were isolated from the Portulaca oleracea L. for the first time. Their structures were elucidated using spectroscopic methods, including one- and two-dimensional nuclear magnetic resonance, high-resolution electrospray ionization time-of-flight mass spectrometry and circular dichroism spectrometry. Oleracone C (1), D (2) and E (4) presented scavenging activities in 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical quenching assay, with IC50 values of 23.27, 11.73, 13.17 µM, respectively and anticholinesterase activities with IC50 values ranging between 59.55 and 78.85 µM.


Assuntos
Flavonoides/isolamento & purificação , Portulaca/química , Inibidores da Colinesterase/isolamento & purificação , Depuradores de Radicais Livres/isolamento & purificação , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Extratos Vegetais/química , Espectrometria de Massas por Ionização por Electrospray
18.
Nat Prod Res ; 32(20): 2431-2436, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29272980

RESUMO

A novel isoindole alkaloid named oleraisoindole (1), together with six known compounds, 7'-ethoxy-trans-feruloyltyramine (2), N-trans-feruloyltyramine (3), N-trans-feruloyl-3-methoxytyramine (4), N-trans-p-coumaroyltyramine (5) aurantiamide (6) and ferulic acid methyl ester (7) were isolated from Portulaca oleracea L. Compounds 2 and 7 were isolated for the first time from this plant. Compound 1 was identified using spectroscopic methods including HR-ESI-TOF-MS, 1D-NMR, 2D-NMR. It was tested in a nitric oxide (NO) inhibition assay and was shown to inhibit NO production in RAW 264.7 cells induced by LPS.


Assuntos
Alcaloides/farmacologia , Isoindóis/farmacologia , Macrófagos/efeitos dos fármacos , Portulaca/química , Alcaloides/isolamento & purificação , Animais , China , Ácidos Cumáricos , Dipeptídeos , Isoindóis/isolamento & purificação , Camundongos , Estrutura Molecular , Óxido Nítrico/metabolismo , Extratos Vegetais/química , Células RAW 264.7
19.
Sci Rep ; 7(1): 11089, 2017 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-28894255

RESUMO

Microbial diversity studies using small subunit (SSU) rRNA gene sequences continue to advance our understanding of biological and ecological systems. Although a good predictor of overall diversity, using this gene to infer the presence of a species in a sample is more controversial. Here, we present a detailed polyphasic analysis of 10 bacterial strains isolated from three coastal lichens Lichina confinis, Lichina pygmaea and Roccella fuciformis with SSU rRNA gene sequences identical to the type strain of Streptomyces cyaneofuscatus. This analysis included phenotypic, microscopic, genetic and genomic comparisons and showed that despite their identical SSU rRNA sequences the strains had markedly different properties, and could be distinguished as 5 different species. Significantly, secondary metabolites profiles from these strains were also found to be different. It is thus clear that SSU rRNA based operational taxonomy units, even at the most stringent cut-off can represent multiple bacterial species, and that at least for the case of Streptomyces, strain de-replication based on SSU gene sequences prior to screening for bioactive molecules can miss potentially interesting novel molecules produced by this group that is notorious for the production of drug-leads.


Assuntos
Metaboloma , Metabolômica , RNA Ribossômico 16S/genética , Metabolismo Secundário , Streptomyces/genética , Streptomyces/metabolismo , Sequenciamento de Nucleotídeos em Larga Escala , Metabolômica/métodos , Fases de Leitura Aberta , Filogenia , Especificidade da Espécie , Esporos Bacterianos , Streptomyces/classificação , Estresse Fisiológico
20.
Front Microbiol ; 8: 1152, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28690598

RESUMO

Quorum sensing (QS) is a density-dependent mechanism allowing bacteria to synchronize their physiological activities, mediated by a wide range of signaling molecules including N-acyl-homoserine lactones (AHLs). Production of AHL has been identified in various marine strains of Proteobacteria. However, the chemical diversity of these molecules still needs to be further explored. In this study, we examined the diversity of AHLs produced by strain MOLA 401, a marine Alphaproteobacterium that belongs to the ubiquitous Rhodobacteraceae family. We combined an original biosensors-based guided screening of extract microfractions with liquid chromatography coupled to mass spectrometry (MS), High Resolution MS/MS and Nuclear Magnetic Resonance. This approach revealed the unsuspected capacity of a single Rhodobacteraceae strain to synthesize 20 different compounds, which are most likely AHLs. Also, some of these AHLs possessed original features that have never been previously observed, including long (up to 19 carbons) and poly-hydroxylated acyl side chains, revealing new molecular adaptations of QS to planktonic life and a larger molecular diversity than expected of molecules involved in cell-cell signaling within a single strain.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA