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1.
Biochimie ; 213: 41-53, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37105301

RESUMEN

Subtilisin-like enzymes are recognized as key players in many infectious agents. In this context, its inhibitors are very valuable molecular lead compounds for structure based drug discovery and design. Marine invertebrates offer a great source of bioactive molecules, including protease inhibitors. In this work, we describe a new subtilisin inhibitor, from the sea anemone Condylactis gigantea (CogiTx1). CogiTx1 was purified using a combination of cation exchange chromatography, size exclusion chromatography and RP-HPLC chromatography. CogiTx1 it is a protein with 46 amino acid residues, with 4970.44 Da and three disulfide bridges. Is also able to inhibit subtilisin-like enzymes and pancreatic elastase. According to the amino acid sequence, it belongs to the defensin 4 family of proteins. The sequencing showed that CogiTx1 has an amidated C-terminal end, which was confirmed by the presence of the typical -XGR signal for amidation in the protein sequence deduced from the cDNA. This modification was described at protein level for the first time in this family of proteins. CogiTx1 is the first subtilisin inhibitor from the defensin 4 family and accordingly it has a folding consisting primarily in beta-strands in agreement with the analysis by CD and 3D modelling. Therefore, future in-depth functional studies may allow a more detailed characterization and will shed light on structure-function properties.


Asunto(s)
Anémonas de Mar , Animales , Anémonas de Mar/química , Anémonas de Mar/metabolismo , Subtilisinas/metabolismo , Secuencia de Aminoácidos , Inhibidores de Proteasas/metabolismo , Defensinas/genética , Defensinas/farmacología
2.
Z Naturforsch C J Biosci ; 75(11-12): 397-407, 2020 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-32609656

RESUMEN

Metallo-aminopeptidases (mAPs) control many physiological processes. They are classified in different families according to structural similarities. Neutral mAPs catalyze the cleavage of neutral amino acids from the N-terminus of proteins or peptide substrates; they need one or two metallic cofactors in their active site. Information about marine invertebrate's neutral mAPs properties is scarce; available data are mainly derived from genomics and cDNA studies. The goal of this work was to characterize the biochemical properties of the neutral APs activities in eight Cuban marine invertebrate species from the Phyla Mollusca, Porifera, Echinodermata, and Cnidaria. Determination of substrate specificity, optimal pH and effects of inhibitors (1,10-phenanthroline, amastatin, and bestatin) and cobalt on activity led to the identification of distinct neutral AP-like activities, whose biochemical behaviors were similar to those of the M1 and M17 families of mAPs. Additionally, M18-like glutamyl AP activities were detected. Thus, marine invertebrates express biochemical activities likely belonging to various families of metallo-aminopeptidases.


Asunto(s)
Secuencia de Aminoácidos/genética , Aminopeptidasas/química , Organismos Acuáticos/enzimología , Invertebrados/enzimología , Aminopeptidasas/antagonistas & inhibidores , Aminopeptidasas/genética , Aminopeptidasas/aislamiento & purificación , Animales , Cuba , Leucina/análogos & derivados , Leucina/farmacología , Péptidos/farmacología , Fenantrolinas/farmacología , Especificidad por Sustrato
3.
Acta Trop ; 185: 63-68, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29684354

RESUMEN

The giant African snail Lissachatina fulica has been reported invading Cuba since 2014 and is now well established in areas of Havana and several nearby regions. This invasive species is of major concern to health authorities given its role as an important vector of parasites such as Angiostrongylus cantonensis, the causative agent of eosinophilic meningoencephalitis in humans. Here, we update the distribution within Cuba. We also report on our studies of experimental life-history traits to assess the population dynamics and potential for spread of this species in Cuba. The experimental population had a very low probability of dying at first age intervals (Type I survival curve) with a life expectancy of 71 weeks. During our experiment, sexual maturity was reached after 22 weeks (individuals of 70 mm shell length) and eggs were laid regularly (mean batch size: 188 ±â€¯111.79 SD). We failed to detect any deviations from the mortality curve and individuals reached an average of 77.3 mm (shell length) and weighted 57.7 g after one year. Predicted curve models indicate that snails reaching their average lifespan of five years should attain 10-12 cm (shell length) and weight 160 g. The spreading of this invasive and vector snail has been tracked for four years in Cuba showing a steady increase of invaded localities. How fast and how far this species develops in Cuba is unknown but the life history parameters indicated in this paper show that it has a large potential to invade all areas of Cuba quickly unless a systematic abatement strategy is developed.


Asunto(s)
Angiostrongylus cantonensis/fisiología , Especies Introducidas , Rasgos de la Historia de Vida , Meningoencefalitis/parasitología , Infecciones por Nematodos/parasitología , Caracoles/fisiología , Caracoles/parasitología , Animales , Cuba , Vectores de Enfermedades , Humanos
4.
Braz. arch. biol. technol ; Braz. arch. biol. technol;47(4): 643-648, Aug. 2004. ilus
Artículo en Inglés | LILACS | ID: lil-365144

RESUMEN

A validação de um método de biópsia ovariana para determinação in vivo da maturação ovocitária em Centropomus parallelus foi descrita. Os diâmetros de ovócitos, obtidos de amostras intra-ovarianas sifonadas por cânula, foram analisados a fresco e preservados com formalina (1%) em solução de NaCl (0,7%). Ovócitos em diferentes estádios de maturação estavam presentes ao longo dos ovários, até o estádio de vitelogênese completa, apresentando uma distribuição de freqüência de diâmetros unimodal. O diâmetro médio dos ovócitos não diferiu significativamente entre as quatro regiões dos ovários (P > 0,05). Amostras obtidas com a cânula são representativas da porção central do ovário, uma vez que as amostras in vivo e in vitro das sete fêmeas examinadas não foram significativamente diferentes (P > 0,05). Uma estimativa do coeficiente de variação corrigido para "bias" (P < 0,05) para oito amostras repetidas in vivo foi de 1,9 ± 0,6. Os resultados demonstraram que para esta espécie, este método de biópsia é satisfatório, provendo amostras representativas dos ovários.

5.
Bol. Inst. Pesca (Impr.) ; 28(2): 125-133, 2002.
Artículo en Portugués | LILACS-Express | VETINDEX | ID: biblio-1464630

RESUMEN

The efficiency of the use of luteinizing hormone-releasing hormone analogue (LHRHa) was tested for the spawning induction of the fat snook, Centropomus parallelus. From January to May 1999, two experiments were carried out. Forty-two females, 525-1,580 g, and 84 males, 324-1,041 g, were submitted to three treatments: injection of 50 µg/kg of LHRHa diluted in saline solution, implantation of a cholesterol pellet with the same dose of the hormone and control, with implantation of a cholesterol pellet without LHRHa. Fish normally spawned once, 35 - 42 h after the hormone was taken. Two females, with cholesterol pellets implanted, spawned twice in a 24 h interval. Considering treatments, there were no significant differences (P>0.05) between the production of eggs and fertilized eggs, and the rates of fertilization and hatching. In the first experiment, the pellet treatment resulted in a mean egg production of 42.27 x 104/kg, a mean fertilization rate of 75.8% and hatching rate of 89.5%. The injection treatment resulted in a mean egg production of 87.11 x 104/kg in a single spawning, with fertilization and hatching rates of 99.0% (spawning of one single female). In the second experiment, the pellet treatment resulted in an average egg production of 45.12 x 104/kg, and average fertilization and hatching rates of 93.8% and 88.0%, respectively. With the injection treatment, ave


A eficiência da utilização do análogo do hormônio liberador do hormônio luteinizante (LHRHa) foi testada na indução da desova do robalo-peva, Centropomus parallelus. De janeiro a maio de 1999 foram realizados dois experimentos com reprodutores (42 fêmeas de 525 a 1.620 g e 84 machos de 324 a 1.041 g) submetidos a três tratamentos: injeção, na dose de 50 µg/kg, de LHRHa diluído em solução salina, implante de pellet de colesterol com a mesma dose do hormônio e o tratamento controle, com aplicação de pellet de colesterol sem LHRHa. As fêmeas geralmente desovaram uma única vez, 35 a 42 h após aplicação hormonal. Duas fêmeas que receberam implante desovaram duas vezes com intervalo de 24 h. Em relação aos tratamentos, não se verificou diferença significativa (P>0,05) entre os valores de produção de óvulos, de ovos fertilizados e das taxas de fertilização e eclosão. No primeiro experimento, o tratamento com pellet apresentou produção média de ovos de 42,27 x 104/kg e taxa média de fertilização de 75,8% e de eclosão de 89,5%. Com injeção, a produção de ovos foi de 87,11 x 104/kg (desova de uma única fêmea) e taxa de fertilização e de eclosão, de 99,0%. No segundo experimento, o tratamento com pellet resultou na produção média de ovos de 45,12 x 104/kg e taxas médias de fertilização e de eclosão, respectivamente, de 93,8% e 88,0%. Com injeção observou-se produção média d

6.
B. Inst. Pesca ; 28(2): 125-133, 2002.
Artículo en Portugués | VETINDEX | ID: vti-761328

RESUMEN

The efficiency of the use of luteinizing hormone-releasing hormone analogue (LHRHa) was tested for the spawning induction of the fat snook, Centropomus parallelus. From January to May 1999, two experiments were carried out. Forty-two females, 525-1,580 g, and 84 males, 324-1,041 g, were submitted to three treatments: injection of 50 µg/kg of LHRHa diluted in saline solution, implantation of a cholesterol pellet with the same dose of the hormone and control, with implantation of a cholesterol pellet without LHRHa. Fish normally spawned once, 35 - 42 h after the hormone was taken. Two females, with cholesterol pellets implanted, spawned twice in a 24 h interval. Considering treatments, there were no significant differences (P>0.05) between the production of eggs and fertilized eggs, and the rates of fertilization and hatching. In the first experiment, the pellet treatment resulted in a mean egg production of 42.27 x 104/kg, a mean fertilization rate of 75.8% and hatching rate of 89.5%. The injection treatment resulted in a mean egg production of 87.11 x 104/kg in a single spawning, with fertilization and hatching rates of 99.0% (spawning of one single female). In the second experiment, the pellet treatment resulted in an average egg production of 45.12 x 104/kg, and average fertilization and hatching rates of 93.8% and 88.0%, respectively. With the injection treatment, ave


A eficiência da utilização do análogo do hormônio liberador do hormônio luteinizante (LHRHa) foi testada na indução da desova do robalo-peva, Centropomus parallelus. De janeiro a maio de 1999 foram realizados dois experimentos com reprodutores (42 fêmeas de 525 a 1.620 g e 84 machos de 324 a 1.041 g) submetidos a três tratamentos: injeção, na dose de 50 µg/kg, de LHRHa diluído em solução salina, implante de pellet de colesterol com a mesma dose do hormônio e o tratamento controle, com aplicação de pellet de colesterol sem LHRHa. As fêmeas geralmente desovaram uma única vez, 35 a 42 h após aplicação hormonal. Duas fêmeas que receberam implante desovaram duas vezes com intervalo de 24 h. Em relação aos tratamentos, não se verificou diferença significativa (P>0,05) entre os valores de produção de óvulos, de ovos fertilizados e das taxas de fertilização e eclosão. No primeiro experimento, o tratamento com pellet apresentou produção média de ovos de 42,27 x 104/kg e taxa média de fertilização de 75,8% e de eclosão de 89,5%. Com injeção, a produção de ovos foi de 87,11 x 104/kg (desova de uma única fêmea) e taxa de fertilização e de eclosão, de 99,0%. No segundo experimento, o tratamento com pellet resultou na produção média de ovos de 45,12 x 104/kg e taxas médias de fertilização e de eclosão, respectivamente, de 93,8% e 88,0%. Com injeção observou-se produção média d

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