Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 5 de 5
Filtrar
Mais filtros

Base de dados
Tipo de estudo
País/Região como assunto
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
Environ Pollut ; 222: 94-100, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28082132

RESUMO

The common soil arthropod Folsomia candida can survive well when fed only maize pollen and thus may be exposed to insecticidal proteins by ingesting insect-resistant genetically engineered maize pollen containing Bacillus thuringiensis (Bt) proteins when being released into the soil. Laboratory experiments were conducted to assess the potential effects of Cry1Ab/Cry2Aj-producing transgenic Bt maize (Shuangkang 12-5) pollen on F. candida fitness. Survival, development, and the reproduction were not significantly reduced when F. candida fed on Bt maize pollen rather than on non-Bt maize pollen, but these parameters were significantly reduced when F. candida fed on non-Bt maize pollen containing the protease inhibitor E-64 at 75 µg/g pollen. The intrinsic rate of increase (rm) was not significantly reduced when F. candida fed on Bt maize pollen but was significantly reduced when F. candida fed on non-Bt maize pollen containing E-64. The activities of antioxidant-related enzymes in F. candida were not significantly affected when F. candida fed on Bt maize pollen but were significantly increased when F. candida fed on non-Bt pollen containing E-64. The results demonstrate that consumption of Bt maize pollen containing Cry1Ab/Cry2Aj has no lethal or sublethal effects on F. candida.


Assuntos
Artrópodes/efeitos dos fármacos , Proteínas de Bactérias/metabolismo , Endotoxinas/metabolismo , Proteínas Hemolisinas/metabolismo , Inseticidas/metabolismo , Controle Biológico de Vetores , Pólen/química , Zea mays , Ração Animal/efeitos adversos , Ração Animal/análise , Animais , Artrópodes/enzimologia , Artrópodes/metabolismo , Toxinas de Bacillus thuringiensis , Proteínas de Bactérias/genética , Proteínas de Bactérias/toxicidade , Toxinas Bacterianas/genética , Toxinas Bacterianas/metabolismo , Toxinas Bacterianas/farmacologia , China , Endotoxinas/genética , Endotoxinas/toxicidade , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/toxicidade , Inseticidas/toxicidade , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Precursores de Proteínas/genética , Precursores de Proteínas/metabolismo , Solo/química
2.
Proc Natl Acad Sci U S A ; 112(34): 10605-10, 2015 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-26261304

RESUMO

Hydroxynitrile lyase (HNL) catalyzes the degradation of cyanohydrins and causes the release of hydrogen cyanide (cyanogenesis). HNL can enantioselectively produce cyanohydrins, which are valuable building blocks for the synthesis of fine chemicals and pharmaceuticals, and is used as an important biocatalyst in industrial biotechnology. Currently, HNLs are isolated from plants and bacteria. Because industrial biotechnology requires more efficient and stable enzymes for sustainable development, we must continuously explore other potential enzyme sources for the desired HNLs. Despite the abundance of cyanogenic millipedes in the world, there has been no precise study of the HNLs from these arthropods. Here we report the isolation of HNL from the cyanide-emitting invasive millipede Chamberlinius hualienensis, along with its molecular properties and application in biocatalysis. The purified enzyme displays a very high specific activity in the synthesis of mandelonitrile. It is a glycosylated homodimer protein and shows no apparent sequence identity or homology with proteins in the known databases. It shows biocatalytic activity for the condensation of various aromatic aldehydes with potassium cyanide to produce cyanohydrins and has high stability over a wide range of temperatures and pH values. It catalyzes the synthesis of (R)-mandelonitrile from benzaldehyde with a 99% enantiomeric excess, without using any organic solvents. Arthropod fauna comprise 80% of terrestrial animals. We propose that these animals can be valuable resources for exploring not only HNLs but also diverse, efficient, and stable biocatalysts in industrial biotechnology.


Assuntos
Acetonitrilas/metabolismo , Aldeído Liases/isolamento & purificação , Aldeídos/metabolismo , Artrópodes/enzimologia , Aldeído Liases/química , Aldeído Liases/metabolismo , Animais , Sequência de Bases , Benzaldeídos/metabolismo , Biocatálise , DNA Complementar/genética , Glicosilação , Concentração de Íons de Hidrogênio , Dados de Sequência Molecular , Estrutura Molecular , Nitrilas/metabolismo , Especificidade de Órgãos , Processamento de Proteína Pós-Traducional , Estrutura Secundária de Proteína , Homologia de Sequência de Aminoácidos , Estereoisomerismo
3.
Zhongguo Zhong Yao Za Zhi ; 37(3): 298-301, 2012 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-22568227

RESUMO

OBJECTIVE: To separate anticoagulant components from the pepsin enzymolysis of centipede by gel filtration and reverse-phase C18 chromatography, and to detect the distribution range of their molecular mass. METHOD: Cingula and 280 nm ultraviolet spectrometry were used to detect and collect the chromatographic solutions. The components' anticoagulant activity in vitro was detected with activated partial thromboplastin time (APTT) as the index, and the molecular mass range of the active composition was detected by MALDI-TOF-MS. RESULT: Anticoagulant active compounds were produced by gel filtration and reverse-phase C18 chromatography. The distribution range of relative molecular mass was determined to be from 597 to 1 146. CONCLUSION: Gel filtration and reverse-phase C18 chromatography are feasible for separating and purifying the pepsin enzymolysis of Centipede. The anticoagulant active compounds are oligopeptides.


Assuntos
Anticoagulantes/isolamento & purificação , Anticoagulantes/metabolismo , Artrópodes/química , Pepsina A/química , Pepsina A/metabolismo , Peptídeos/isolamento & purificação , Peptídeos/metabolismo , Animais , Artrópodes/enzimologia , Cromatografia Líquida de Alta Pressão , Masculino , Tempo de Tromboplastina Parcial , Coelhos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
4.
Biochim Biophys Acta ; 444(3): 835-52, 1976 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-186109

RESUMO

1. Limulus hepatopancreas, coxal glands and intestine contain a particulate enzyme which can synthesize glucose 6-phosphate from glucose and inorganic pyrophosphate or carbamyl phosphate as well as hydrolyze glucose 6-phosphate. This has been clearly differentiated from hydrolysis by lysosomal or soluble phosphatases. 2. The enzyme resembles vertebrate glucose-6-phosphatase in its specific anatomical distribution, pH optimum, kinetic properties, donor specificity and phospholipid dependence, as indicated by its satency and lability to detergent treatment. 3. A variety of other invertebrates tested exhibited little or no PPi-glucose phosphotransferase activity with these properties. A similar phosphotransferase activity of lobster hepatopancreas had somewhat different kinetic properties and pH optimum. 4. The hypothesis that a specific glucose-6-phosphatase is to be found only in those animals which utilize free glucose as an important circulating form of energy is presented and discussed. It appears that a variety of transport compounds, such as trehalose and glucose, was tried at the evolutionary level of the Arthropods.


Assuntos
Artrópodes/enzimologia , Evolução Biológica , Glucose-6-Fosfatase/metabolismo , Caranguejos Ferradura/enzimologia , Microssomos Hepáticos/enzimologia , Fosfotransferases/metabolismo , Animais , Cinética , Fígado/enzimologia , Lisossomos/enzimologia , Microssomos/enzimologia , Nephropidae/enzimologia , Especificidade de Órgãos , Pâncreas/enzimologia , Polietilenoglicóis/farmacologia , Pirofosfatases/metabolismo , Ratos , Especificidade da Espécie
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA