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1.
Org Lett ; 18(22): 5792-5795, 2016 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-27934498

RESUMO

Coprisidins A and B (1 and 2) were isolated from a gut-associated Streptomyces sp. in the dung beetle Copris tripartitus. Using a combination of spectroscopic techniques, the structures of the compounds were determined to be the first examples of natural naphthoquinone-oxindole alkaloids. Coprisidin A was found to inhibit the action of Na+/K+-ATPase, and coprisidin B showed activity for the induction of NAD(P)H:quinone oxidoreductase 1.


Assuntos
Alcaloides/isolamento & purificação , Besouros/microbiologia , Alcaloides Indólicos/isolamento & purificação , Intestinos/microbiologia , Naftoquinonas/isolamento & purificação , Streptomyces/química , Animais , Estrutura Molecular , Streptomyces/isolamento & purificação
2.
Org Lett ; 17(5): 1272-5, 2015 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-25686280

RESUMO

Coprisamides A and B (1 and 2) were isolated from a bacterium in the gut of the dung beetle Copris tripartitus. Spectroscopic analysis revealed that the planar structures of 1 and 2 are novel cyclic heptapeptides bearing unusual units, such as ß-methylaspartic acid and 2,3-diaminopropanoic acid branched to valine and 2-heptatrienyl cinnamic acid. Absolute configurations were established by chemical derivatization and chiroptical spectroscopy. The coprisamides displayed significant activity for induction of quinone reductase.


Assuntos
Fenômenos Fisiológicos Bacterianos/efeitos dos fármacos , Besouros/microbiologia , Peptídeos Cíclicos/química , Streptomyces/química , beta-Alanina/análogos & derivados , Animais , Fezes , Estrutura Molecular , Peptídeos Cíclicos/isolamento & purificação , beta-Alanina/química
3.
Org Lett ; 15(8): 1834-7, 2013 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-23550720

RESUMO

Tripartin (1), a new dichlorinated indanone, was isolated from the culture broth of the Streptomyces sp. associated with a larva of the dung beetle Copris tripartitus Waterhouse. The planar structure of tripartin (1) was identified by the spectroscopic analyses of NMR, mass, UV, and IR data. The structure was confirmed, and the absolute configuration of 1 was determined by X-ray crystallography. Tripartin displayed specific activity as an inhibitor of the histone H3 lysine 9 demethylase KDM4 in HeLa cells.


Assuntos
Besouros/microbiologia , Histona Desmetilases/antagonistas & inibidores , Hidrocarbonetos Clorados/isolamento & purificação , Hidrocarbonetos Clorados/farmacologia , Indanos/isolamento & purificação , Indanos/farmacologia , Animais , Cristalografia por Raios X , Células HeLa , Humanos , Hidrocarbonetos Clorados/química , Indanos/química , Larva/microbiologia , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Streptomyces/química
4.
Org Lett ; 14(5): 1258-61, 2012 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-22360311

RESUMO

Tripartilactam, a structurally unprecedented cyclobutane-bearing tricyclic lactam metabolite, was discovered from Streptomyces sp. isolated from a brood ball of the dung beetle, Copris tripartitus. The structure of this compound was elucidated by the combination of NMR, MS, UV, and IR spectroscopy and multistep chemical derivatization. Tripartilactam was evaluated as a Na(+)/K(+) ATPase inhibitor (IC(50) = 16.6 µg/mL).


Assuntos
Besouros/microbiologia , Ciclobutanos/química , Fezes/microbiologia , Lactamas/química , Inibidores de Simportadores de Cloreto de Sódio e Potássio/química , Streptomyces/química , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Ciclobutanos/isolamento & purificação , Ciclobutanos/farmacologia , Humanos , Lactamas/isolamento & purificação , Lactamas/farmacologia , Estrutura Molecular , Inibidores de Simportadores de Cloreto de Sódio e Potássio/isolamento & purificação , Inibidores de Simportadores de Cloreto de Sódio e Potássio/farmacologia , Streptomyces/isolamento & purificação
5.
Bioorg Med Chem Lett ; 21(19): 5715-8, 2011 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-21873059

RESUMO

Two new phenylpyridines, named coprismycins A and B (1 and 2), and previously reported dipyridines (3-6) were isolated from a culture of Streptomyces sp. associated with the dung beetle, Copris tripartitus. The structures of the coprismycins (1 and 2) were elucidated by the analysis of 1D and 2D NMR spectra and mass, UV, and IR spectra. Coprismycins A-B (1 and 2) and dipyridines (5 and 6) displayed comparable neuroprotective effects against MPP(+) (1-methyl-4-phenylpyrimidium)-induced neurotoxicity in neuroblastoma SH-SY5Y cells.


Assuntos
Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/farmacologia , Síndromes Neurotóxicas , Oximas/química , Oximas/farmacologia , Piridinas/química , Piridinas/farmacologia , Streptomyces/química , 1-Metil-4-fenilpiridínio/toxicidade , Animais , Linhagem Celular Tumoral , Sobrevivência Celular , Besouros/microbiologia , Dopamina/metabolismo , Descoberta de Drogas , Estrutura Molecular , Neuroblastoma , Fármacos Neuroprotetores/isolamento & purificação , Fármacos Neuroprotetores/toxicidade , Síndromes Neurotóxicas/tratamento farmacológico , Síndromes Neurotóxicas/prevenção & controle , Oximas/isolamento & purificação , Oximas/toxicidade , Transtornos Parkinsonianos/tratamento farmacológico , Transtornos Parkinsonianos/prevenção & controle , Piridinas/isolamento & purificação , Piridinas/toxicidade
6.
Vet Parasitol ; 178(3-4): 324-9, 2011 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-21324598

RESUMO

The toxicity of two cassia oils, four cinnamon oils and (E)-cinnamaldehyde and (E)-cinnamic acid and 34 structurally related compounds to adult Dermanyssus gallinae (De Geer) collected from a poultry house was examined using a vapour-phase mortality bioassay. Results were compared with those of dichlorvos, a conventional acaricide. The cassia and cinnamon oils (cinnamon technical, cinnamon #500, cassia especial, cassia true, cinnamon bark and cinnamon green leaf) exhibited good fumigant toxicity (LD(50), 11.79-26.40 µg cm(-3)). α-Methyl-(E)-cinnamaldehyde (LD(50), 0.45 µg cm(-3)) and (E)-cinnamaldehyde (0.54 µg cm(-3)) were the most toxic compounds and the toxicity of these compounds was comparable to that of dichlorvos (0.30 µg cm(-3)). Potent fumigant toxicity was also observed in allyl cinnamate, ethyl-α-cyanocinnamate, (E)-2-methoxylcinnamic acid and (Z)-2-methoxylcinnamic acid (LD(50), 0.81-0.92 µg cm(-3)). Structure-activity relationships indicate that structural characteristics, such as types of functional groups and carbon skeleton rather than vapour pressure parameter, appear to play a role in determining toxicity. The essential oils and compounds described merit further study as potential acaricides for the control of D. gallinae populations as fumigants with contact action due to global efforts to reduce the level of highly toxic synthetic acaricides in the agricultural environment.


Assuntos
Ácaros e Carrapatos , Cassia/química , Cinamatos/química , Cinnamomum zeylanicum/química , Fumigação/métodos , Óleos de Plantas , Animais , Modelos Lineares , Relação Estrutura-Atividade
7.
Arch Environ Contam Toxicol ; 60(1): 99-106, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20437041

RESUMO

The hazardous effects on the earthworm numbers and biomass of eight consecutive yearly applications of three levels (12.5, 25, and 50 tons of dry matter/ha/y) of four different organic sludges (municipal sewage, industrial sewage, alcohol fermentation processing, and leather processing) to earthworm-free soils were examined using field lysimeters. Results were compared with those of pig manure compost (PMC)-treated soil. Of five species (Amynthas agrestis, A. sangyeoli, A. hupeiensis, Drawida koreana, and D. japonica) from 390 adult specimens collected 4 and 8 years after treatment, the number of species appeared to be lower in sludge-treated soils than in PMC-treated soils. Earthworm populations and biomass were correlated negatively with the pollution index [∑(heavy-metal concentration in soil/tolerable level)/number of heavy metal] 4 and 8 years after treatment. These results suggest that the long-term application of these sludges, particularly from industrial sewage and leather processing, might affect adversely the establishment of Megascolecid and Moniligastrid earthworms in field conditions.


Assuntos
Metais Pesados/toxicidade , Oligoquetos/efeitos dos fármacos , Oligoquetos/fisiologia , Esgotos/efeitos adversos , Poluentes do Solo/toxicidade , Solo/química , Animais , Biomassa , Esterco/análise , Metais Pesados/análise , Densidade Demográfica , República da Coreia , Esgotos/análise , Esgotos/química , Solo/análise , Poluentes do Solo/análise , Poluentes do Solo/química , Curtume
8.
Int J Pept ; 20092009.
Artigo em Inglês | MEDLINE | ID: mdl-20721297

RESUMO

The antibacterial activity of immune-related peptides, identified by a differential gene expression analysis, was investigated to suggest novel antibacterial peptides. A cDNA encoding a defensin-like peptide, Coprisin, was isolated from bacteria-immunized dung beetle, Copris tripartitus, by using differential dot blot hybridization. Northern blot analysis showed that Coprisin mRNA was up-regulated from 4 hours after bacteria injection and its expression level was reached a peak at 16 hours. The deduced amino acid sequence of Coprisin was composed of 80 amino acids with a predicted molecular weight of 8.6 kDa and a pI of 8.7. The amino acid sequence of mature Coprisin was found to be 79.1% and 67.4% identical to those of defensin-like peptides of Anomala cuprea and Allomyrina dichotoma, respectively. We also investigated active sequences of Coprisin by using amino acid modification. The result showed that the 9-mer peptide, LLCIALRKK-NH(2), exhibited potent antibacterial activities against Escherichia coli and Staphylococcus aureus.

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