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1.
ACS Biomater Sci Eng ; 8(2): 493-501, 2022 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-35030308

RESUMO

Enzymatic decontamination of organophosphate compounds offers a biofriendly pathway to the neutralization of highly dangerous compounds. Environmental dissemination of enzymes, however, is an ongoing problem considering the costly process of production and chemical modification for stability that can diminish catalytic activity. As a result, there is interest in the potential for enzymatic encapsulation in situ or into nascent bacterial membrane vesicles to improve catalytic stability across various environmental challenges associated with storage and field deployment. In this study, we have engineered bacterial outer membrane vesicles (OMVs) to encapsulate the diisopropyl fluorophosphatase (DFPase), an enzyme originally isolated from squid Loligo vulgaris and capable of hydrolyzing diisopropyl fluorophosphate (DFP) and other organophosphates compounds. Here we employed a recombinant lipopeptide anchor to direct recruitment of DFPase into OMVs, which were isolated from culture media and tested for catalytic activity against both diisopropyl fluorophosphate and paraoxon. Our encapsulation strategy prevented the loss of catalytic activity despite lyophilization, extended storage time (2 days), and extreme temperatures up to 80 °C. These data underscore the appeal of DFPase as a biodecontaminant of organophosphates as well as the potential for OMV packaging in stabilized field deployment applications.


Assuntos
Loligo , Hidrolases de Triester Fosfórico , Animais , Membrana Externa Bacteriana , Loligo/metabolismo , Hidrolases de Triester Fosfórico/química , Hidrolases de Triester Fosfórico/metabolismo , Temperatura
2.
J Food Sci ; 86(10): 4316-4329, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34519066

RESUMO

Squid are commercial marine species that have high nutritional value. This study aimed to compare the influences of vacuum frying and atmospheric frying on the physicochemical properties and protein oxidation of three main parts (ring, tentacle, and fin) of the squid Loligo chinensis. The results showed that the vacuum-fried (VF) group had lower moisture and total fat contents and looser microstructures than the atmospheric-fried (AF) group. The amino acid contents and molecular weight revealed that the proteins were well preserved during vacuum frying. Carbonyl content in the VF ring, tentacle, and fin samples increased nearly 2.53-, 1.54-, and 2.56-fold, respectively, compared to that in the corresponding fresh group, but these increases were lower than those of the corresponding AF group. In addition, the secondary structures of proteins revealed a slight decrease in the α-helix and ß-turn contents and a significant increase in the ß-sheet content during vacuum frying. Therefore, vacuum frying can be used as an efficient processing method to conserve the high nutritive quality of the product. PRACTICAL APPLICATION: As a developing alternative technology to prepare healthier fried products, vacuum frying has been the focus of recent researches. Vacuum frying produced squid products that had lower TBARS values, carbonyl contents, and Schiff base substances compared to atmospheric frying. And the protein secondary structures of the vacuum-fried group retained better. The study proved that vacuum frying could be an effective method with the advantages of high protein stability and product quality.


Assuntos
Culinária , Decapodiformes , Proteínas na Dieta , Qualidade dos Alimentos , Loligo , Animais , Decapodiformes/química , Proteínas na Dieta/metabolismo , Análise de Alimentos , Loligo/química , Oxirredução , Vácuo
3.
Mar Drugs ; 19(7)2021 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-34356809

RESUMO

The growing requirement for sustainable processes has boosted the development of biodegradable plastic-based materials incorporating bioactive compounds obtained from waste, adding value to these products. Chitosan (Ch) is a biopolymer that can be obtained by deacetylation of chitin (found abundantly in waste from the fishery industry) and has valuable properties such as biocompatibility, biodegradability, antimicrobial activity, and easy film-forming ability. This study aimed to produce and characterize poly(lactic acid) (PLA) surfaces coated with ß-chitosan and ß-chitooligosaccharides from a Loligo opalescens pen with different molecular weights for application in the food industry. The PLA films with native and depolymerized Ch were functionalized through plasma oxygen treatment followed by dip-coating, and their physicochemical properties were assessed by Fourier-transform infrared spectroscopy, X-ray diffraction, water contact angle, and scanning electron microscopy. Their antimicrobial properties were assessed against Escherichia coli and Pseudomonas putida, where Ch-based surfaces reduced the number of biofilm viable, viable but nonculturable, and culturable cells by up to 73%, 74%, and 87%, respectively, compared to PLA. Biofilm growth inhibition was confirmed by confocal laser scanning microscopy. Results suggest that Ch films of higher molecular weight had higher antibiofilm activity under the food storage conditions mimicked in this work, contributing simultaneously to the reuse of marine waste.


Assuntos
Antibacterianos/farmacologia , Quitosana/química , Loligo , Animais , Organismos Aquáticos , Biofilmes/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Embalagem de Alimentos , Peso Molecular , Espectroscopia de Infravermelho com Transformada de Fourier
4.
Ecotoxicol Environ Saf ; 203: 110957, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32888620

RESUMO

Due to growing commercial interest as a fishing resource and its intermediate position in the marine trophic chains as both prey and predator, cephalopods can play an important role in mercury (Hg) transfer along the marine food webs, since they can bioaccumulate this metal in its tissues. Our study aims to analyze Hg accumulation in Loligo forbesi caught in the Azores Archipelago (Portugal) quantifying Hg in different tissues (mantle and stomach), as well in the squid stomach content, in order to evaluate the efficiency of Hg transfer from prey to predator. Hg data from the tissues was used to estimate the weekly tolerable Hg intake due to squid consumption. Overall data indicate that Hg measured in the stomach tissue (0.1 ± 0.01 µg g-1) was significantly higher than Hg levels found in the mantle (0.04 ± 0.001 µg g-1) and stomach contents (0.01 ± 0.001 µg g-1). BMF (bioaccumulation factor) was >1 for all the samples, indicating a biomagnification process from prey to predator. Hg concentration in the mantle tissue was correlated with mantle size; although females present higher Hg levels than males, the difference was found to be not related to gender but rather to the fact that females had larger bodies. Finally, considering the Hg concentration found in the mantle and the permitted Hg levels, it is advisable to consume up to 1050-1890g of squid per week, according to the regulatory agencies. Thus, our results indicate that, since these doses are respected, consumption of squids from the Azorean waters do not pose a risk to humans.


Assuntos
Bioacumulação , Exposição Dietética/análise , Monitoramento Ambiental/métodos , Loligo/metabolismo , Mercúrio/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Feminino , Cadeia Alimentar , Humanos , Masculino , Mercúrio/análise , Portugal , Alimentos Marinhos/análise , Poluentes Químicos da Água/análise
5.
Environ Pollut ; 255(Pt 2): 113282, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31563788

RESUMO

Chokka squid (Loligo reynaudii) from three sites along the South African coast were analyzed for halogenated natural products (HNPs) and anthropogenic persistent organic pollutants (POPs). HNPs were generally more than one order of magnitude more abundant than POPs. The most prevalent pollutant, i.e. the HNP 2,3,3',4,4',5,5'-heptachloro-1'-methyl-1,2'-bipyrrole (Q1), was detected in all chokka squid samples with mean concentrations of 105, 98 and 45 ng/g lipid mass, respectively, at the Indian Ocean (site A), between both oceans (site B) and the South Atlantic Ocean (site C). In addition, bromine containing polyhalogenated 1'-methyl-1,2'-bipyrroles (PMBPs), 2,4,6-tribromophenol (2,4,6-TBP, up to 28 ng/g lipid mass), polybrominated methoxy diphenyl ethers, MHC-1, TBMP and other HNPs were also detected. Polychlorinated biphenyls (PCBs) were the predominant class of anthropogenic POPs. PCB 153 was the most abundant PCB congener in chokka squid from the Indian Ocean, and PCB 138 in samples from the South Atlantic Ocean and between both oceans.


Assuntos
Monitoramento Ambiental , Loligo/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Oceano Atlântico , Produtos Biológicos , Poluentes Ambientais , Éteres Difenil Halogenados/análise , Halogenação , Oceano Índico , Loligo/química , Bifenilos Policlorados , Alimentos Marinhos , África do Sul , Poluentes Químicos da Água/análise
6.
Nat Commun ; 10(1): 3188, 2019 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-31320630

RESUMO

A diversity of self-propelled chemical motors, based on Marangoni propulsive forces, has been developed in recent years. However, most motors are non-functional due to poor performance, a lack of control, and the use of toxic materials. To overcome these limitations, we have developed multifunctional and biodegradable self-propelled motors from squid-derived proteins and an anesthetic metabolite. The protein motors surpass previous reports in performance output and efficiency by several orders of magnitude, and they offer control of their propulsion modes, speed, mobility lifetime, and directionality by regulating the protein nanostructure via local and external stimuli, resulting in programmable and complex locomotion. We demonstrate diverse functionalities of these motors in environmental remediation, microrobot powering, and cargo delivery applications. These versatile and degradable protein motors enable design, control, and actuation strategies in microrobotics as modular propulsion sources for autonomous minimally invasive medical operations in biological environments with air-liquid interfaces.


Assuntos
Loligo/metabolismo , Proteínas Motores Moleculares/síntese química , Proteínas Motores Moleculares/metabolismo , Robótica/instrumentação , Animais , Recuperação e Remediação Ambiental , Nanoestruturas/química
7.
Comput Biol Chem ; 77: 272-278, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30396154

RESUMO

Organophosphate compounds bioremediation by use of organophosphorus degradation enzymes such as DFPase is a developing interest in industry and medicine. The most important problem with the bio-catalytic enzymes is their instability on high temperatures. This work carried out to find suitable locations for introducing disulfide bridges in DFPase enzyme. We employed some computational approaches to design the disulfide bridges and evaluate their roles in the enzyme structural thermostability. According to the in silico results, mutant 6 (V24C, C76) increased the enzyme thermostability relative to wild-type.


Assuntos
Loligo/enzimologia , Hidrolases de Triester Fosfórico/química , Animais , Domínio Catalítico , Bases de Dados de Proteínas , Dissulfetos/química , Estabilidade Enzimática , Temperatura Alta , Loligo/química , Loligo/genética , Simulação de Dinâmica Molecular , Hidrolases de Triester Fosfórico/genética , Mutação Puntual , Conformação Proteica
8.
J Biomol Struct Dyn ; 36(12): 3094-3105, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28884632

RESUMO

A recently introduced electrostatic-based method to determine the pKa values of ionizable residues and fractions of ionized and tautomeric forms of histidine (His) and acid residues in proteins, at a given fixed pH, is applied here to the analysis of a His-rich protein, namely Loligo vulgaris (pdb id 1E1A), a 314-residue all-ß protein. The average tautomeric fractions for the imidazole ring of each of the six histidines in the sequence were computed using an approach that includes, but is not limited to, molecular dynamic simulations coupled with calculations of the ionization states for all 94 ionizable residues of protein 1E1A in water at pH 6.5 and 300 K. The electrostatic-calculated tautomeric fractions of the imidazole ring of His were compared with predictions obtained from an existent NMR-based methodology. Our results indicate that: (i) the averaged electrostatic-based tautomeric predictions for the imidazole ring of all histidines of Loligo vulgaris are dominated by the Nε2-H rather than the Nδ1-H form, although such preferences from the NMR-based methodology are not so well defined; (ii) the computed average absolute difference between the electrostatic- and the NMR-based tautomeric predictions among all six histidines vary among 0% to 17%; (iii) for the His showing the largest fraction of the neutral form (81%), the absolute difference between the NMR- and electrostatic-based computed tautomeric predictions is only 3%; and (iv) the tautomeric predictions for the imidazole ring of His computed with the NMR-based methodology are stable within a certain, well-defined, range of variations of a tautomer-related parameter.


Assuntos
Histidina/química , Imidazóis/química , Loligo/química , Animais , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Simulação de Acoplamento Molecular , Proteínas/química , Eletricidade Estática
9.
Int J Biol Macromol ; 93(Pt A): 442-447, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27593242

RESUMO

Squid pens were extracted by a NaOH solution at 80°C for 10h to remove protein and minerals. The as-prepared ß-chitin had a high molecular weight (8.5±0.1×103kDa), a low protein content (0.63±0.02wt.%), and a negligible amount of minerals. This method avoids the conventional method for the removal of minerals from shrimp and crab shells by HCl. The purity of resulting products was measured by NMR and FTIR. Moreover, the morphology and crystallinity of ß-chitin was characterized by SEM and XRD. The ß-chitin with long chains and high purity is suitable for producing high quantity ß-chitosan for various potential applications.


Assuntos
Quitina/química , Quitina/isolamento & purificação , Loligo/química , Animais
10.
Parasite ; 23: 33, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27530149

RESUMO

Chromidina spp. are enigmatic apostome ciliates (Oligohymenophorea, Opalinopsidae) that parasitise the renal and pancreatic appendages of cephalopods. Only four species have been described, among which only three have been formally named. No DNA sequence has been reported so far. To investigate Chromidina spp. diversity, we sampled cephalopods in the Mediterranean Sea off Tunis, Tunisia, and identified two distinct Chromidina spp. in two different host species: Loligo vulgaris and Sepia officinalis. From haematoxylin-stained slides, we described morphological traits for these parasitic species and compared them to previous descriptions. We also re-described the morphology of Chromidina elegans (Foettinger, 1881) from Chatton and Lwoff's original materials and designated a neohapantotype and paraneohapantotypes for this species. We describe a new species, Chromidina chattoni Souidenne, Florent and Grellier n. sp., found in L. vulgaris off Tunisia, and evidence for a probable novel species, found in S. officinalis off Tunisia, although this latter species presents similarities to some morphological stages previously described for Chromidina cortezi Hochberg, 1971. We amplified, for the first time, an 18S rDNA marker for these two Chromidina species. Phylogenetic analysis supports the association of Chromidina within apostome ciliates. Genetic distance analysis between 18S rDNA sequences of representative apostomes indicates Pseudocollinia as the most closely related genus to Chromidina.


Assuntos
Cefalópodes/parasitologia , Oligoimenóforos/classificação , Filogenia , Animais , Teorema de Bayes , DNA Ribossômico/química , França , Funções Verossimilhança , Loligo/parasitologia , Mar Mediterrâneo , Oligoimenóforos/genética , Oligoimenóforos/ultraestrutura , RNA Ribossômico 18S/genética , Sepia/parasitologia , Alinhamento de Sequência , Tunísia
11.
Int J Biol Macromol ; 87: 504-13, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26972602

RESUMO

Acid-Solubilized Collagen (ASC) and Pepsin-Solubilized Collagen (PSC) were extracted from the mantle of the common European squid, and were comparatively characterized. ASC and PSC were isolated with an extraction yield of 5.1 and 24.2% (on dry weight basis), respectively. SDS-PAGE showed that the ASC was mostly comprised of α1- and α2-chains; while the PSC presented relevant ß- and γ-components. GPC analysis confirmed that both the ASC and the PSC consisted of fractions characterized by different molecular weight. Thermal denaturation behavior of ASC and PSC were followed by calorimetric and rheological analyses; denaturation temperature was estimated to be 22°C for ASC and 21°C for PSC. Amino acid composition and solubility of collagen were also investigated. Finally, the cytotoxicity of the isolated collagen was evaluated in vitro and no cytotoxic activity caused by the collagen extracts was observed. This study demonstrated that squid mantle has potential as an alternative source of collagen-derived materials.


Assuntos
Colágeno/química , Colágeno/isolamento & purificação , Loligo/química , Animais , Colágeno/toxicidade , Concentração de Íons de Hidrogênio , Camundongos , Peso Molecular , Células NIH 3T3 , Desnaturação Proteica , Solubilidade , Temperatura , Viscosidade
12.
PLoS One ; 11(2): e0146995, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26872354

RESUMO

Polyandry is widespread and influences patterns of sexual selection, with implications for sexual conflict over mating. Assessing sperm precedence patterns is a first step towards understanding sperm competition within a female and elucidating the roles of male- and female-controlled factors. In this study behavioural field data and genetic data were combined to investigate polyandry in the chokka squid Loligo reynaudii. Microsatellite DNA-based paternity analysis revealed multiple paternity to be the norm, with 79% of broods sired by at least two males. Genetic data also determined that the male who was guarding the female at the moment of sampling was a sire in 81% of the families tested, highlighting mate guarding as a successful male tactic with postcopulatory benefits linked to sperm deposition site giving privileged access to extruded egg strings. As females lay multiple eggs in capsules (egg strings) wherein their position is not altered during maturation it is possible to describe the spatial / temporal sequence of fertilisation / sperm precedence There were four different patterns of fertilisation found among the tested egg strings: 1) unique sire; 2) dominant sire, with one or more rare sires; 3) randomly mixed paternity (two or more sires); and 4) a distinct switch in paternity occurring along the egg string. The latter pattern cannot be explained by a random use of stored sperm, and suggests postcopulatory female sperm choice. Collectively the data indicate multiple levels of male- and female-controlled influences on sperm precedence, and highlights squid as interesting models to study the interplay between sexual and natural selection.


Assuntos
Copulação/fisiologia , Fertilização/fisiologia , Padrões de Herança , Loligo/genética , Preferência de Acasalamento Animal/fisiologia , Seleção Genética , Animais , Feminino , Masculino , Repetições de Microssatélites , Reprodução/genética , Espermatozoides/fisiologia , Zigoto/fisiologia
13.
Int J Biol Macromol ; 82: 614-20, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26526178

RESUMO

Beta-chitosan has a parallel structure, which differs from alpha-chitosan's antiparallel structure while producing different properties and difficulties. In this paper, we prepared the beta-chitosan through acid and alkali methods and the resultant material was characterized by elemental analysis, FT-IR, HPLC, XRD, NMR and AFS. To increase the solubility and biological activity of the beta-chitosan, we degraded it through microwave-assisted process. After characterization, we determined that the chitosan had not changed its configuration during the reaction with H2O2 under microwave irradiation. The inhibitory activity of the degraded chitosan for Newcastle disease was revealed by a hemagglutination test and RT-PCR. The yield of the beta-chitosan was approximately 30%, and its molecular weight can be degraded to 1000 to 10,000g/mol. Moreover, the degraded ß-chitosan has higher antiviral activity, reducing the hemagglutination titre to zero, compared with alpha-chitosan. Therefore, beta-chitosan has good development prospects during the development of veterinary drugs for Newcastle disease.


Assuntos
Antivirais/química , Antivirais/farmacologia , Quitosana/química , Quitosana/farmacologia , Loligo/química , Animais , Embrião de Galinha , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Doença de Newcastle/tratamento farmacológico , Doença de Newcastle/virologia , Vírus da Doença de Newcastle/efeitos dos fármacos , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
14.
Mitochondrial DNA A DNA Mapp Seq Anal ; 27(6): 4278-4279, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-26486876

RESUMO

In this study, we determined the complete mitochondrial genome of Loligo beka. The genome was 17 483 bp in length and contained 13 protein-coding genes, 22 transfer RNA genes, two ribosomal RNA genes, and three main non-coding regions. The overall base composition of L.beka is A 40.35%, T 32.53%, C 18.53%, and G 8.58%, with a highly A + T bias of 72.89%. All the three control regions (CR) contain termination-associated sequences and conserved sequence blocks. Here we describe a phylogenetic analysis of 11 species cephalopoda based on the complete mitochondrial genome, the result showed that the Loliolus uyii is most closely related to L. beka. This mitogenome sequence data would play an important role in the investigation of phylogenetic relationship, taxonomic resolution and phylogeography of the cephalopoda.


Assuntos
DNA Mitocondrial/genética , Genoma Mitocondrial/genética , Loligo/genética , Animais , Composição de Bases/genética , Sequência de Bases/genética , Ordem dos Genes/genética , Genes Mitocondriais/genética , Filogenia , Análise de Sequência de DNA/métodos
15.
Mitochondrial DNA A DNA Mapp Seq Anal ; 27(4): 2723-4, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26104158

RESUMO

In this study, we determined the complete mitochondrial genome of the little squid (Loligo duvaucelii). The genome is 17,413 bp in length, containing 13 protein-coding genes, 22 transfer RNA genes, 2 ribosomal RNA genes and 3 main non-coding regions. The overall base composition of L. duvaucelii is 40.01% A, 32.33% T, 19.14% C and 8.52% G, with a high A + T bias of 72.34%. All of the three control regions (CR) contain termination-associated sequences and conserved sequence blocks. Here, we describe a phylogenetic analysis of 10 species of Cephalopoda based on the complete mitochondrial genome, the result showed that the Loliolus uyii is most closely related to L. duvaucelii. This mitogenome sequence data would play an important role in the investigation of phylogenetic relationship, taxonomic resolution and phylogeography of the Cephalopoda.


Assuntos
Genoma Mitocondrial/genética , Loligo/genética , Animais , Composição de Bases/genética , DNA Mitocondrial/genética , Ordem dos Genes/genética , Loligo/classificação , Filogenia , RNA Ribossômico/genética , RNA de Transferência/genética , Análise de Sequência de DNA
16.
Mitochondrial DNA A DNA Mapp Seq Anal ; 27(5): 3337-8, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-25703845

RESUMO

In this study, we determined the complete mitochondrial genome of the Loligo opalescence. The genome was 17,370 bp in length and contained 13 protein-coding genes, 22 transfer RNA genes, 2 ribosomal RNA genes and 3 main non-coding regions. The composition and order of genes, were similar to most other invertebrates. The overall base composition of L. opalescence is A 38.62%, C 19.40%, T 32.37% and G 9.61%, with a highly A + T bias of 70.99%. All of the three control regions (CR) contain termination-associated sequences and conserved sequence blocks. This mitogenome sequence data would play an important role in the investigation of phylogenetic relationship, taxonomic resolution and phylogeography of the Loliginidae.


Assuntos
Genoma Mitocondrial , Loligo/genética , Animais , Composição de Bases , Códon , Sequência Conservada , Ordem dos Genes , Genes Mitocondriais , Tamanho do Genoma , Loligo/classificação , Fases de Leitura Aberta , Sequências Reguladoras de Ácido Nucleico , Análise de Sequência de DNA , Sequenciamento Completo do Genoma
17.
J Vet Med Sci ; 78(1): 43-7, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26369293

RESUMO

The digestive organs in decapodiform cephalopod species morphologically vary by individual lifestyle. We examined the following six species of adult decapodiformes cephalopods representing different habitats: Todarodes pacificus, Loligo bleekeri, Loligo edulis, Watasenia scintillans (pelagic), Sepia lycidas and Euprymna morsei (benthic). L. bleekeri and L. edulis possess a bursiform cecal sac connected to the cecum. Pelagic species have a single digestive gland smaller than in benthic species. T. pacificus has an oval digestive gland larger than that of L. bleekeri and L. edulis, which possess withered-looking and smaller digestive glands. In contrast, the digestive glands in benthic species are paired. S. lycidas and E. morsei have well-developed and larger digestive glands than those of the pelagic species. Well-developed digestive duct appendages are found in benthic species. In qualification of the mass of digestive organs, pelagic species have smaller stomachs, digestive glands and digestive ducts' appendages than benthic species. Because pelagic species need to swim, they may possess smaller stomachs and larger cecums for more rapid digestion. A smaller digestive gland may have the advantage of reducing the body weight in pelagic species for rapid swimming. In contrast, since benthic species require a longer time for digestion than pelagic species, they compact more food in their stomachs and absorb nutrients via more organs, such as the digestive grand and digestive duct appendages, in addition to cecum.


Assuntos
Cefalópodes/anatomia & histologia , Sistema Digestório/anatomia & histologia , Animais , Ceco/anatomia & histologia , Ceco/fisiologia , Cefalópodes/fisiologia , Decapodiformes/anatomia & histologia , Decapodiformes/fisiologia , Fenômenos Fisiológicos do Sistema Digestório , Intestinos/anatomia & histologia , Intestinos/fisiologia , Loligo/anatomia & histologia , Loligo/fisiologia , Sepia/anatomia & histologia , Sepia/fisiologia , Estômago/anatomia & histologia , Estômago/fisiologia
18.
Int J Biol Macromol ; 72: 1143-51, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25301697

RESUMO

The characteristics, biological properties, and purification of sulfated polysaccharides extracted from squid (Loligo vulgaris) skin were investigated. Their chemical and physical characteristics were determined using X-ray diffraction and infrared spectroscopic analysis. Sulfated polysaccharides from squid skin (SPSS) contained 85.06% sugar, 2.54% protein, 1.87% ash, 8.07% sulfate, and 1.72% uronic acid. The antioxidant properties of SPSS were investigated based on DPPH radical-scavenging capacity (IC50 = 19.42 mg mL(-1)), hydrogen peroxide-scavenging activity (IC50 = 0.91 mg mL(-1)), and ß-carotene bleaching inhibition (IC50 = 2.79 mg mL(-1)) assays. ACE-inhibitory activity of SPSS was also investigated (IC50 = 0.14 mg mL(-1)). Further antimicrobial activity assays indicated that SPSS exhibited marked inhibitory activity against the bacterial and fungal strains tested. Those polysaccharides did not display hemolytic activity towards bovine erythrocytes. Fractionation by DEAE-cellulose column chromatography showed three major absorbance peaks. Results of this study suggest that sulfated polysaccharides from squid skin are attractive sources of polysaccharides and promising candidates for future application as dietary ingredients.


Assuntos
Loligo/química , Polissacarídeos/isolamento & purificação , Polissacarídeos/farmacologia , Pele/química , Sulfatos/isolamento & purificação , Sulfatos/farmacologia , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Animais , Antibacterianos/farmacologia , Antifúngicos/farmacologia , Antioxidantes/farmacologia , Bovinos , Cromatografia DEAE-Celulose , Cromatografia por Troca Iônica , Sequestradores de Radicais Livres/farmacologia , Hemólise/efeitos dos fármacos , Peróxido de Hidrogênio/química , Testes de Sensibilidade Microbiana , Peptidil Dipeptidase A/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X , beta Caroteno/química
19.
J Phys Chem B ; 118(17): 4479-89, 2014 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-24720808

RESUMO

Organophosphorus (OP) nerve agents such as (S)-sarin are among the most highly toxic compounds that have been synthesized. Engineering enzymes that catalyze the hydrolysis of nerve agents ("bioscavengers") is an emerging prophylactic approach to diminish their toxic effects. Although its native function is not known, diisopropyl fluorophosphatase (DFPase) from Loligo vulgaris catalyzes the hydrolysis of OP compounds. Here, we investigate the mechanisms of diisopropylfluorophosphate (DFP) and (S)-sarin hydrolysis by DFPase with quantum mechanical/molecular mechanical umbrella sampling simulations. We find that the mechanism for hydrolysis of DFP involves nucleophilic attack by Asp229 on phosphorus to form a pentavalent intermediate. P-F bond dissociation then yields a phosphoacyl enzyme intermediate in the rate-limiting step. The simulations suggest that a water molecule, coordinated to the catalytic Ca(2+), donates a proton to Asp121 and then attacks the tetrahedral phosphoacyl intermediate to liberate the diisopropylphosphate product. In contrast, the calculated free energy barrier for hydrolysis of (S)-sarin by the same mechanism is highly unfavorable, primarily because of the instability of the pentavalent phosphoenzyme species. Instead, simulations suggest that hydrolysis of (S)-sarin proceeds by a mechanism in which Asp229 could activate an intervening water molecule for nucleophilic attack on the substrate. These findings may lead to improved strategies for engineering DFPase and related six-bladed ß-propeller folds for more efficient degradation of OP compounds.


Assuntos
Substâncias para a Guerra Química/metabolismo , Isoflurofato/metabolismo , Hidrolases de Triester Fosfórico/metabolismo , Engenharia de Proteínas , Sarina/metabolismo , Animais , Hidrólise , Loligo/enzimologia , Modelos Moleculares , Hidrolases de Triester Fosfórico/química , Hidrolases de Triester Fosfórico/genética , Conformação Proteica , Termodinâmica
20.
Biochem Biophys Res Commun ; 450(3): 1218-24, 2014 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-24768636

RESUMO

In the coastal squid Loligo bleekeri, each male produces one of two types of fertilization-competent spermatozoa (eusperm) that exhibit morphological and behavioral differences. Large "consort" males produce short-tailed spermatozoa that display free-swimming behavior when ejaculated into seawater. Small "sneaker" males, on the other hand, produce long-tailed spermatozoa that exhibit a self-swarming trait after ejaculation. To understand the molecular basis for adaptive traits employed by alternative male mating tactics, we performed the transcriptome deep sequencing (RNA-seq) and proteome analyses to search for differences in testicular mRNAs and sperm proteins, respectively. From mature male testes we identified a total of 236,455 contigs (FPKM ≧1) where 3789 and 2789 were preferentially (≧10-fold) expressed in consort and sneaker testes, respectively. A proteomic analysis detected 4302 proteins in the mature sperm as post-translational products. A strongly biased (≧10-fold) distribution occurred in 55 consort proteins and 61 sneaker proteins. There was no clear mRNA-protein correlation, making a ballpark estimate impossible for not only overall protein abundance but also the degree of biased sperm type expressed in the spermatozoa. A family encoding dynein heavy chain gene, however, was found to be biased towards sneakers, whereas many enzymes involving energy metabolism were heavily biased towards consort spermatozoa. The difference in flagellar length matched exactly the different amount of tubulins. From these results we hypothesize that discrete differential traits in dimorphic eusperm arose from a series of innovative alterations in the intracellular components of spermatozoa.


Assuntos
Loligo/citologia , Loligo/metabolismo , Proteínas/metabolismo , Espermatozoides/citologia , Espermatozoides/metabolismo , Animais , Dineínas/genética , Dineínas/metabolismo , Loligo/genética , Masculino , Processamento de Proteína Pós-Traducional , Proteínas/genética , Proteoma , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Espermatozoides/classificação , Transcriptoma
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