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1.
Appl Environ Microbiol ; 89(3): e0218622, 2023 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-36847541

RESUMO

Cytochrome P450 enzymes are promising biocatalysts for industrial use because they catalyze site-selective C-H oxidation and have diverse catalytic reactions and a broad substrate range. In this study, the 2α-hydroxylation activity of CYP154C2 from Streptomyces avermitilis MA-4680T toward androstenedione (ASD) was identified by an in vitro conversion assay. The testosterone (TES)-bound structure of CYP154C2 was solved at 1.42 Å, and this structure was used to design eight mutants, including single, double, and triple mutants, to improve the conversion efficiency. Mutants L88F/M191F and M191F/V285L were found to enhance the conversion rates significantly (i.e., 8.9-fold and 7.4-fold for TES, 46.5-fold and 19.5-fold for ASD, respectively) compared with the wild-type (WT) enzyme while retaining high 2α-position selectivity. The substrate binding affinity of the L88F/M191F mutant toward TES and ASD was enhanced compared with that of WT CYP154C2, supporting the measured increase in the conversion efficiencies. Moreover, the total turnover number and kcat/Km of the L88F/M191F and M191F/V285L mutants increased significantly. Interestingly, all mutants containing L88F generated 16α-hydroxylation products, suggesting that L88 in CYP154C2 plays a vital role in substrate selectivity and that the amino acid corresponding to L88 in the 154C subfamily affects the orientation of steroid binding and substrate selectivity. IMPORTANCE Hydroxylated derivatives of steroids play essential roles in medicine. Cytochrome P450 enzymes selectively hydroxylate methyne groups on steroids, which can dramatically change their polarity, biological activity and toxicity. There is a paucity of reports on the 2α-hydroxylation of steroids, and documented 2α-hydroxylate P450s show extremely low conversion efficiency and/or low regio- and stereoselectivity. This study conducted crystal structure analysis and structure-guided rational engineering of CYP154C2 and efficiently enhanced the conversion efficiency of TES and ASD with high regio- and stereoselectivity. Our results provide an effective strategy and theoretical basis for the 2α-hydroxylation of steroids, and the structure-guided rational design of P450s should facilitate P450 applications in the biosynthesis of steroid drugs.


Assuntos
Sistema Enzimático do Citocromo P-450 , Esteroides , Hidroxilação , Esteroides/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Oxirredução , Testosterona/metabolismo , Especificidade por Substrato
2.
Int J Syst Evol Microbiol ; 72(12)2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36748603

RESUMO

A Gram-stain-negative, aerobic, chemoheterotrophic and rod-shaped strain, designated as C5T, was isolated from intertidal surface seawater in Taizhou, Zhejiang Province, PR China and characterized using a polyphasic taxonomic approach. Strain C5T could produce carotenoids and bacteriochlorophyll a. Growth was observed at 20-45 °C, at pH 6.0-9.0 and with 0-8.0 % (w/v) NaCl. The 16S rRNA gene sequence identity analysis revealed that strain C5T was the most closely related to Qipengyuania nanhaisediminis CGMCC 1.7715T (98.8%) and Erythrobacter litoralis DSM 8509T (98.7%). The phylogenetic reconstruction based on core genes demonstrated that strain C5T was clustered into the members of the genus Erythrobacter. The average nucleotide identity and digital DNA-DNA hybridization values between strain C5T and Erythrobacter type strains were lower than 76 and 25 %, respectively. The predominant and minor respiratory quinones were identified as ubiquinone-10 and ubiquinone-9. The major fatty acids were summed feature 8 (C18 : 1 ω7c and/or C18 : 1 ω6c) and iso-C18 : 0. Polar lipids included phosphatidylethanolamine, phosphatidylglycerol, a glycosphingolipid and an unidentified aminolipid. Based on the genetic, chemotaxonomic and phenotypic data, strain C5T is concluded to represent a novel species in the genus Erythrobacter, for which the name Erythrobacter aurantius sp. nov. is proposed. The type strain is C5T (=MCCC 1K05108T=KCTC 92307T).


Assuntos
Ácidos Graxos , Sphingomonadaceae , Ácidos Graxos/química , Fosfolipídeos/química , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Composição de Bases , DNA Bacteriano/genética , Técnicas de Tipagem Bacteriana , Água do Mar
3.
Chem Biodivers ; 19(5): e202200177, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35426465

RESUMO

Cytochrome P450 enzymes (CYPs or P450s) are ubiquitous heme-dependent enzymes that catalyze the monooxygenation of non-activated C-H bonds to modify the structure of the substrate. In this study, we heterologously expressed CYP107X1 from Streptomyces avermitilis and conducted in vitro substrate screening using the alternative redox partners putidaredoxin and putidaredoxin reductase. CYP107X1 catalyzed the 16α-hydroxylation of progesterone with regio- and stereoselectivity. The spectroscopic analyses showed that CYP107X1 bound progesterone with a relatively high Kd value of 65.3±38.9 µM. The Km and kcat values for progesterone were estimated to be 47.7±12.0 µM and 0.30 min-1 , respectively. Furthermore, a crystal structure was obtained of CYP107X1 bound with glycerol from the buffer solution. Interestingly, a conserved threonine was replaced with asparagine in CYP107X1, indicating that it may adopt an unnatural proton transfer process and play a crucial role in its catalytic activity.


Assuntos
Progesterona , Streptomyces , Sistema Enzimático do Citocromo P-450/metabolismo , Hidroxilação , Progesterona/metabolismo , Streptomyces/metabolismo
4.
Arch Microbiol ; 204(1): 86, 2021 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-34961889

RESUMO

Three yellow-pigmented, Gram-stain-negative, aerobic, motile by flagella and rod-shaped strains, designated as MCT, PC and RC, were isolated from stems of Populus euphratica. Growth of those three strains occurs at 4-40 °C, pH 6.0-10.0 and with 0.5-18.0% (w/v) NaCl. Respiratory quinones contained ubiquinone-9 and ubiquione-8 as major and minor components, respectively. Major fatty acids (> 10%) were summed feature 8 (C18:1ω6c and/or C18:1ω7c), summed feature 3 (C16:1ω6c and/or C16:1ω7c) and C16:0. Polar lipids included diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, two unidentified phospholipids, one unidentified aminolipid, one unidentified glycolipid and four unidentified lipids. Strains MCT, PC and RC shared pairwise 16S rRNA gene sequence similarities of 99.9-100.0%, and showed higher similarities of 98.4-98.5% with Halomonas songnenensis NEAU-ST10-39T and 98.3-98.4% with Halomonas nanhaiensis YIM M 13059T than to other Halomonas type strains. Genomic comparisons revealed that those three strains had the pan-genome consisting of 4446 orthologous clusters, among which 676 orthologous clusters were absent in other Halomonas type strains. Phylogenomic tree indicated that strains MCT, PC and RC formed an independently stable clade with Halomonas nanhaiensis YIM M 13059T and Halomonas songnenensis NEAU-ST10-39T. The average nucleotide identity and digital DNA-DNA hybridization values between those three strains and other Halomonas type strains were < 89.9% and < 39.3%, respectively. Based upon phenotypic, chemotaxonomic, phylogenetic and genomic results, strains MCT, PC and RC represent a novel species in the genus Halomonas, for which the name Halomonas populi sp. nov. is proposed. The type strain is MCT (= JCM 33545T = MCCC 1K03942T).


Assuntos
Halomonas , Populus , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/análise , Halomonas/genética , Fosfolipídeos/análise , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
5.
Arch Microbiol ; 203(8): 5133-5139, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34319420

RESUMO

A Marinomonas-like, Gram-stain-negative, strictly aerobic and rod to ovoid-shaped bacterium, designated as strain A79T, was isolated from the seawater mixtures of oyster shells and brown algae in a coastal intertidal zone of Zhoushan, China. The strain was positive for oxidase and catalase. Colonies grown on marine agar for 48 h were round, milky white, smooth and moist with the diameter of 2-3 mm. Growth was observed at 15-30 °C (optimum, 25℃), pH 5.5-9.5 (optimum, pH 8.5) and with 0.5-8% (w/v) NaCl (optimum, 2-2.5%). The G + C content based on the genome sequence was 46.0%. The only respiratory quinone was Q-8. The main polar lipids contained phosphatidylglycerol, phosphatidylethanolamine, unidentified glycolipids, unidentified phospholipid and three unidentified lipids. The major fatty acids (> 10%) were C16:0, Summed feature 3 (comprising C16:1 ω6c and/or C16:1 ω7c) and summed feature 8 (comprising C18:1 ω6c and/or C18:1 ω7c). The 16S rRNA gene sequence similarity between strain A79T and Marinomonas pollencensis IVIA-Po-185T was 97.4%, the similarities with other type strains of the genus Marinomonas were 93.8-96.7%. Based on the results, Marinomonas vulgaris sp. nov. was proposed as a novel species. The type strain is A79T (= MCCC 1K05799T = KCTC 82519T = JCM 34473T).


Assuntos
Marinomonas , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos , Marinomonas/genética , Hibridização de Ácido Nucleico , Fosfolipídeos , Filogenia , RNA Ribossômico 16S/genética , Água do Mar , Análise de Sequência de DNA
6.
Chem Biodivers ; 18(4): e2000910, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33656282

RESUMO

Cytochrome P450 enzymes (P450s) are versatile biocatalysts, which insert a molecular oxygen into inactivated C-H bonds under mild conditions. CYP105D7 from Streptomyces avermitilis has been reported as a bacterial substrate-promiscuous P450 which catalyzes the hydroxylation of 1-deoxypentalenic acid, diclofenac, naringenin, compactin and steroids. In this study, CYP105D7 catalyzes hydroxylation, epoxidation and dehydrogenation of capsaicin, a pharmaceutical agent, revealing its functional diversity. The kinetic parameters of the CYP105D7 oxidation of capsaicin were determined as Km =311.60±87.30 µM and kcat =2.01±0.33 min-1 . In addition, we conducted molecular docking, mutagenesis and substrate binding analysis, indicating that Arg81 plays crucial role in the capsaicin binding and catalysis. To our best knowledge, this study presents the first report to illustrate that capsaicin can be catalyzed by prokaryotic P450s.


Assuntos
Capsaicina/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Streptomyces/enzimologia , Biocatálise , Capsaicina/química , Hidrogenação , Hidroxilação , Simulação de Acoplamento Molecular , Estrutura Molecular
7.
Fish Shellfish Immunol ; 84: 704-710, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30359751

RESUMO

Japanese eel (Anguilla japonica) has become a commercially important fish species all over the world. High-density aquaculture has led to congestion and contributed to bacterial infection outbreaks that have caused high mortality. Therefore a 56-days feeding trial was conducted to determine the effects of dietary Bacillus amyloliquefaciens (GB-9) and Yarrowia lipolytica lipase2 (YLL2) on growth performance, digestive enzymes activity, innate immunity and resistance to pathogens of A. japonica. Fish growth performance was significantly affected by dietary YLL2 supplementation but not by GB-9. Fish fed diets with YLL2 at 2.0 g/kg diet in combination of high and low levels of GB-9 (5.0 g/kg and 2.0 g/kg) produced the highest growth. For digestive enzyme, lipase and trypsin activities was promoted by dietary containing YLL2, while amylase activities was increased by dietary containing YLL2, GB-9 single or combination. For innate immunity, the mucus lysozyme activity, leukocytes phagocytosis activity and reactive oxygen species level of skin, peroxidase and lysozyme activity of serum were enhanced in fish fed with GB-9 compared to those in control group (p < 0.05). The highest resistance to Vibrio anguillarum and Aeromonas hydrophila was determined in fish fed with 5.0 g kg-1 GB-9 + 2.0 g/kg YLL2. This study demonstrated that GB-9 and YLL2 enhanced non-specific immune defense system of A. japonica, providing them with higher resistance to pathogens. The present results suggested that the combination of these supplements could be considered as potential biological additives for aquaculture farmed fish.


Assuntos
Anguilla/imunologia , Bacillus amyloliquefaciens/química , Hidrolases de Éster Carboxílico/administração & dosagem , Doenças dos Peixes/imunologia , Proteínas Fúngicas/administração & dosagem , Imunidade Inata/efeitos dos fármacos , Imunidade nas Mucosas/efeitos dos fármacos , Probióticos/farmacologia , Aeromonas hydrophila/fisiologia , Anguilla/crescimento & desenvolvimento , Anguilla/metabolismo , Animais , Dieta/veterinária , Suplementos Nutricionais/análise , Relação Dose-Resposta a Droga , Trato Gastrointestinal/enzimologia , Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Negativas/veterinária , Distribuição Aleatória , Vibrio/fisiologia , Vibrioses/imunologia , Vibrioses/veterinária
8.
Mar Drugs ; 17(12)2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31766406

RESUMO

A pair of stereoisomers possessing novel structures with 6/6/5 fused-ring systems, neo-debromoaplysiatoxin E (1) and neo-debromoaplysiatoxin F (2), were isolated from the marine cyanobacterium Lyngbya sp. Their structures were elucidated using various spectroscopic techniques including high resolution electrospray ionization mass spectroscopy (HRESIMS) and nuclear magnetic resonance (NMR). The absolute stereochemistry was determined by calculated electronic circular dichroism (ECD) and gauge-independent atomic orbital (GIAO) NMR shift calculation followed by DP4+ analysis. Significantly, this is the first report on aplysiatoxin derivatives with different absolute configurations at C9-C12 (1: 9S, 10R, 11S, 12S; 2: 9R, 10S, 11R, 12R). Compounds 1 and 2 exhibited potent blocking activities against Kv1.5 with IC50 values of 1.22 ± 0.22 µM and 2.85 ± 0.29 µM, respectively.


Assuntos
Organismos Aquáticos/química , Cianobactérias/química , Canal de Potássio Kv1.5/antagonistas & inibidores , Toxinas de Lyngbya/farmacologia , Animais , Células CHO , Dicroísmo Circular , Cricetulus , Canal de Potássio Kv1.5/metabolismo , Toxinas de Lyngbya/química , Toxinas de Lyngbya/isolamento & purificação , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Estereoisomerismo
9.
Mar Drugs ; 17(9)2019 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-31454987

RESUMO

Bacterial secondary metabolites have huge application potential in multiple industries. Biosynthesis of bacterial secondary metabolites are commonly encoded in a set of genes that are organized in the secondary metabolism biosynthetic gene clusters (SMBGCs). The development of genome sequencing technology facilitates mining bacterial SMBGCs. Marine Streptomyces is a valuable resource of bacterial secondary metabolites. In this study, 87 marine Streptomyces genomes were obtained and carried out into comparative genomic analysis, which revealed their high genetic diversity due to pan-genomes owning 123,302 orthologous clusters. Phylogenomic analysis indicated that the majority of Marine Streptomyces were classified into three clades named Clade I, II, and III, containing 23, 38, and 22 strains, respectively. Genomic annotations revealed that SMBGCs in the genomes of marine Streptomyces ranged from 16 to 84. Statistical analysis pointed out that phylotypes and ecotypes were both associated with SMBGCs distribution patterns. The Clade I and marine sediment-derived Streptomyces harbored more specific SMBGCs, which consisted of several common ones; whereas the Clade II and marine invertebrate-derived Streptomyces have more SMBGCs, acting as more plentiful resources for mining secondary metabolites. This study is beneficial for broadening our knowledge about SMBGC distribution patterns in marine Streptomyces and developing their secondary metabolites in the future.


Assuntos
Organismos Aquáticos/genética , Genes Bacterianos , Família Multigênica , Metabolismo Secundário/genética , Streptomyces/genética , Organismos Aquáticos/metabolismo , Produtos Biológicos/metabolismo , Vias Biossintéticas/genética , Genômica , Filogenia , Streptomyces/metabolismo
10.
Fish Shellfish Immunol ; 82: 250-257, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30125703

RESUMO

A 12-weeks feeding trial was performed to investigate the possible effects of supplementation of Hybrid sturgeon diet with Bacillus amyloliquefaciens (GB-9) and Yarrowia lipolytica lipase2 (YLL2) single or combined on immune response and growth performance of Hybrid sturgeon (Acipenser schrenkii ♂and Acipenser baeri ♀). For this aim, Hybrid sturgeons were fed with four experimental diets namely: Diet 1 (0-control), Diet 2 (5.0 g/kg GB-9), Diet 3 (4.0 g/kg YLL2), and Diet 4 (5.0 g/kg GB-9 + 4.0 g/kg YLL2), respectively. After fed with varied diets, growth performance, mucosal immune response, leukocytes immune response and serum immunological response were measured. The results indicated that supplementations of GB-9 + YLL2 resulted in a significant increase in final weight, Docosahexaenoic acid (DHA) and Eicosapentenoic acid (EPA) concentration, compared with that of control (p < 0.05). For innate immunity, the results showed that skin mucus lysozyme activity, leukocytes phagocytosis activity and reactive oxygen species level, and serum alternative complement pathway activity, peroxidase and lysozyme activity were significantly higher in supplemented groups compared to the control (p < 0.05). The highest values were recorded in fish fed both YLL2 and GB-9 with respect to the individual application. The present results suggested that the combination of these supplementation could be considered as potential feed-additives for aquaculture farmed fish.


Assuntos
Bacillus amyloliquefaciens/química , Hidrolases de Éster Carboxílico/administração & dosagem , Peixes/crescimento & desenvolvimento , Peixes/imunologia , Proteínas Fúngicas/administração & dosagem , Probióticos/farmacologia , Ração Animal/análise , Animais , Cruzamento , Dieta/veterinária , Suplementos Nutricionais/análise , Imunidade Inata/efeitos dos fármacos , Imunidade nas Mucosas/efeitos dos fármacos , Distribuição Aleatória
11.
Chem Pharm Bull (Tokyo) ; 66(6): 602-607, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29863061

RESUMO

Dolastatin 16 is a cyclic depsipeptide isolated from the marine invertebrates and cyanobacterium Lyngbya majuscula, however, its bioactivity has been a historical question. In this study, peptidyl-prolyl cis-trans isomerase FKBP1A (FKBP12) was predicted as a potential target of dolastatin 16 via PharmMapper as well as verified using chemical-protein interactome (CPI) and molecular docking. FKBP1A has been previously identified as a target for the natural polyketide FK506 (tacrolimus), an immune suppressor inhibiting the rejection of organ transplantation in clinical use. The comparison study via the reverse pharmacophore screening and molecular docking of dolastatin 16 and FK506 indicated the good consistency of analysis with the computational approach. As the results, the lowest binding energy of dolastatin 16-FKBP1A complex was -7.4 kcal/mol and FK506-FKBP1A complex was -8.7 kcal/mol. The ligand dolastatin 16 formed three hydrogen bonds vs. four of FK506, as well as seven hydrophobic interactions vs. six of FK506 within the active site residues. These functional residues are highly repetitive and consistent with previously reported active site of model of FK506-FKBP1A complex, and the pharmacophore model was shown feasibly matching with the molecular feature of dolastatin 16.


Assuntos
Depsipeptídeos/farmacologia , Simulação de Acoplamento Molecular , Proteínas de Ligação a Tacrolimo/antagonistas & inibidores , Depsipeptídeos/química , Avaliação Pré-Clínica de Medicamentos , Humanos , Modelos Moleculares , Conformação Molecular , Tacrolimo/química , Tacrolimo/farmacologia
12.
Int J Syst Evol Microbiol ; 67(10): 4024-4031, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28893367

RESUMO

A Gram-staining-negative, aerobic, non-spore-forming, coccoid to rod shaped bacteria with prosthecate and flagellum, designated as HSF6T, was isolated from deep seawater samples collected from the South China Sea at depth of 2.5 km and subjected to a polyphasic taxonomic investigation. Colonies of strain HSF6T were 1-2 mm in diameter, smooth, circular, convex and yellow. Strain HSF6T was found to grow at 15-37 °C (optimum, 25-35 °C), pH 5.0-9.5 (optimum, pH 7.0-7.5) and with 0-8 % (w/v) NaCl (optimum, 2 %). Chemotaxonomic analysis showed the predominant respiratory quinone of strains HSF6T were ubiquinone-10, and the major fatty acids were C18 : 1ω7c, C16 : 0 and 11-methyl C18 : 1ω7c. The polar lipids were monoglycosyldiglyceride (MGDG), sulfo-quinovosyl diacylglycerol (SQDG), three unknown glycolipids (GL1-3) and five unknown lipids (L1-5). The DNA G+C content of strain HSF6T was determined to be 51.0 mol% with HPLC. The comparison of 16S rRNA gene sequence similarities show that strain HSF6T was related most closely to genus Parvularcula with similarity ranging from 91.0 to 91.8 %. The phylogenetic trees, using the 16S rRNA gene sequence, reconstructed with neighbour-joining, maximum-parsimony and maximum-likelihood methods showed that strain HSF6T constituted a separated branch in the family 'Parvularculaceae'. Differential phenotypic properties, together with the phylogenetic distinctiveness, demonstrated that strain HSF6T is clearly distinct from validly published genera. On the basis of these features, we propose strain HSF6T (=MCCC 1K03223T=KCTC 52486T) represents a novel species of a novel genus with the name Hyphococcus flavus gen. nov., sp. nov.


Assuntos
Alphaproteobacteria/classificação , Filogenia , Água do Mar/microbiologia , Alphaproteobacteria/genética , Alphaproteobacteria/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Glicolipídeos/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ubiquinona/química
13.
Bioorg Med Chem ; 25(24): 6614-6622, 2017 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-29153548

RESUMO

A new trichodermamide-like alkaloid, N-Me-trichodermamide B (compound 1), was isolated from a marine fungus Penicillium janthinellum HDN13-309. The structure and absolute configuration of compound 1 were determined by extensive NMR analysis and the modified Mosher's method. This new alkaloid exhibited cellular protection from the H2O2-induced oxidative damage, and the mechanism study revealed that this antioxidant activity was regulated through Nrf2-mediated signaling pathway in HaCaT human keratinocytes. In addition, the inhibitor of p38 abrogated compound 1-induced phosphorylation of p38, up-expression of HO-1, and the nuclear localization of Nrf2. As a result, it suggested that this new alkaloid-induced antioxidant signaling pathway might be initiated through activation of p38.


Assuntos
Antioxidantes/farmacologia , Dipeptídeos/farmacologia , Fator 2 Relacionado a NF-E2/antagonistas & inibidores , Penicillium/química , Transdução de Sinais/efeitos dos fármacos , Antioxidantes/química , Antioxidantes/isolamento & purificação , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Dipeptídeos/química , Dipeptídeos/isolamento & purificação , Relação Dose-Resposta a Droga , Humanos , Estrutura Molecular , Fator 2 Relacionado a NF-E2/metabolismo , Relação Estrutura-Atividade
14.
J Nat Prod ; 80(5): 1436-1445, 2017 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-28398051

RESUMO

Nine new sesquiterpene quinones/hydroquinones (1-7, 10, and 12), three solvent-generated artifacts (8, 9, and 11), and three known compounds, 5-epi-smenospongine (13), smenospongine (14), and smenospongiadine (15), were isolated from the marine sponge Spongia pertusa Esper. The planar structures of the new compounds were elucidated on the basis of spectroscopic analyses. Their absolute configurations were determined by comparison between the calculated and experimental ECD spectra. In the cytotoxicity bioassay, compounds 13-15 exhibited activities against the human cancer cell lines U937, HeLa, and HepG2, with most potent cytotoxicities to U937 cells with IC50 values of 2.8, 1.5, and 0.6 µM, respectively. In addition, compound 6 displayed CDK-2 affinity with a Kd value of 4.8 µM in a surface plasmon resonance assay.


Assuntos
Células Hep G2/efeitos dos fármacos , Hidroquinonas/isolamento & purificação , Hidroquinonas/farmacologia , Poríferos/química , Quinonas/farmacologia , Sesquiterpenos/isolamento & purificação , Sesquiterpenos/farmacologia , Animais , Ensaios de Seleção de Medicamentos Antitumorais , Células HeLa , Humanos , Hidroquinonas/química , Concentração Inibidora 50 , Estrutura Molecular , Quinonas/química , Quinonas/isolamento & purificação , Sesquiterpenos/química
15.
J Org Chem ; 81(12): 5135-43, 2016 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-27232542

RESUMO

Fifteen polyketides, including the first hydroxylated plakortone (12) and plakdiepoxide (15), the first polyketide to embed a vicinal diepoxide, have been isolated from the Chinese sponge Plakortis simplex. The structures of the new metabolites were elucidated by analysis of spectroscopic data, Mosher's derivatization, and DFT computational calculations. The reactivity of the major endoperoxide of this sponge was investigated, suggesting that furan, furanylidene, and plakilactone derivatives, well-known classes of natural products, could actually be chemical degradation products. Plakdiepoxide is a potent and selective modulator of peroxisome proliferator-activated receptor (PPAR)-γ, while the diunsaturated C12 fatty acid monotriajaponide (13) activates both PPAR-α and PPAR-γ, a dual activity of potential great importance for the treatment of metabolic disorders.

16.
J Nat Prod ; 79(8): 2045-52, 2016 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-27489998

RESUMO

Three new cyclohexadepsipeptides, oryzamides A-C (1-3), two isolation artifacts, oryzamides D (4) and E (5), and the known congener scopularide A (6), all possessing a rare 3-hydroxy-4-methyldecanoic acid (HMDA) substructure, were isolated from the mycelial extract of the sponge-derived fungus Nigrospora oryzae PF18. Their planar structures were elucidated by spectroscopic analysis and comparison with the literature data. The absolute configurations were determined using the advanced Marfey's method and single-crystal X-ray diffraction analysis. Among them, oryzamides D (4) and E (5) were a pair of diastereomers at the sulfur atom of the l-methionine sulfoxide residue, which showcased the possible separation of a pair of methionine sulfoxide diastereomers. The X-ray crystal structure of scopularide A (6) was obtained for the first time, thereby establishing its relative and absolute configuration at C-4 of the HMDA residue. Oryzamides A-C (1-3) did not display cytotoxic, antibacterial, antiparasitic, and NF-κB inhibitory activities.


Assuntos
Ascomicetos/química , Poríferos/microbiologia , Animais , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Cristalografia por Raios X , Depsipeptídeos/química , Depsipeptídeos/isolamento & purificação , Ensaios de Seleção de Medicamentos Antitumorais , Biologia Marinha , Metionina/análogos & derivados , Metionina/química , Fungos Mitospóricos , Conformação Molecular , Estrutura Molecular , NF-kappa B/efeitos dos fármacos
17.
J Nat Prod ; 79(2): 406-11, 2016 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-26863083

RESUMO

Four new tetracyclic meroterpnes, dysiherbols A-C (1-3) and dysideanone E (4), were isolated from a Dysidea sp. marine sponge collected from the South China Sea. Their complete structures and absolute configurations were unambiguously determined by a combination of NMR spectroscopic data, ECD calculations, and single-crystal X-ray diffraction analysis. Within the sesquiterpene quinol structures, dysiherbols A-C possess an intriguing 6/6/5/6-fused tetracyclic carbon skeleton. The NF-κB inhibitory and cytotoxic activity evaluation disclosed that dysiherbol A (1) showed potent activity with respective IC50 values of 0.49 and 0.58 µM, which were about 10-fold and 20-fold more potent than those of dysiherbols B (2) and C (3), which feature hydroxy and ketone carbonyl groups at the C-3 position.


Assuntos
Antineoplásicos , Dysidea/química , NF-kappa B/antagonistas & inibidores , Sesquiterpenos , Animais , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Cristalografia por Raios X , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Concentração Inibidora 50 , Biologia Marinha , Conformação Molecular , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação , Sesquiterpenos/farmacologia , Relação Estrutura-Atividade
18.
Mar Drugs ; 14(11)2016 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-27886049

RESUMO

Since the 1990s, a number of terminal alkynyl residue-containing cyclic/acyclic peptides have been identified from marine organisms, especially cyanobacteria and marine mollusks. This review has presented 66 peptides, which covers over 90% marine peptides with terminal alkynyl fatty acyl units. In fact, more than 90% of these peptides described in the literature are of cyanobacterial origin. Interestingly, all the linear peptides featured with terminal alkyne were solely discovered from marine cyanobacteria. The objective of this article is to provide an overview on the types, structural characterization of these unusual terminal alkynyl fatty acyl units, as well as the sources and biological functions of their composed peptides. Many of these peptides have a variety of biological activities, including antitumor, antibacterial, antimalarial, etc. Further, we have also discussed the evident biosynthetic origin responsible for formation of terminal alkynes of natural PKS (polyketide synthase)/NRPS (nonribosome peptide synthetase) hybrids.


Assuntos
Alcinos/química , Organismos Aquáticos/química , Produtos Biológicos/química , Peptídeos/química , Alcinos/farmacologia , Produtos Biológicos/farmacologia , Cianobactérias/química , Humanos , Peptídeo Sintases/metabolismo , Peptídeos/farmacologia , Policetídeo Sintases/metabolismo
19.
Mar Drugs ; 13(9): 5579-92, 2015 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-26343687

RESUMO

Two new furan derivatives, hypofurans A and B (1 and 2), and three new cyclopentenone derivatives, hypocrenones A-C (3-5), along with seven known compounds (6-12), were isolated from a marine fungus Hypocrea koningii PF04 associated with the sponge Phakellia fusca. Among them, compounds 10 and 11 were obtained for the first time as natural products. The planar structures of compounds 1-5 were elucidated by analysis of their spectroscopic data. Meanwhile, the absolute configuration of 1 was determined as 2R,3R by the comparison of the experimental and calculated electronic circular dichroism (ECD) spectra. All the isolates were evaluated for their antibacterial and antioxidant activity. Compounds 1, 10, and 12 all showed modest antibacterial activity against Staphylococcus aureus ATCC25923 (MIC, 32 µg/mL). In addition, compounds 1, 10 and 11 exhibited moderate DPPH radical scavenging capacity with IC50 values of 27.4, 16.8, and 61.7 µg/mL, respectively.


Assuntos
Ciclopentanos/metabolismo , Furanos/metabolismo , Hypocrea/metabolismo , Poríferos/microbiologia , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Ciclopentanos/química , Furanos/química , Estrutura Molecular
20.
J Asian Nat Prod Res ; 17(12): 1231-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26699877

RESUMO

Three new aaptamine derivatives (1-3), together with six known related compounds (4-9), have been isolated from the South China Sea sponge Aaptos aaptos. The structures of all compounds were unambiguously elucidated on the basis of spectroscopic analyses. Compounds 1, 4, 5, 7, and 9 showed cytotoxic activities against HeLa, K562, MCF-7, and U937 cell lines with IC50 values in the range of 0.90-12.32 µM.


Assuntos
Antineoplásicos/isolamento & purificação , Naftiridinas/isolamento & purificação , Poríferos/química , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , China , Ensaios de Seleção de Medicamentos Antitumorais , Células HeLa , Humanos , Células K562 , Biologia Marinha , Estrutura Molecular , Naftiridinas/química , Naftiridinas/farmacologia , Células U937
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