RESUMO
Fucoidan is a well-known natural product that is commonly found in brown algae and shows a variety of activities, including immunomodulation, antioxidation, and the combat of carcinogens. The fucoidan fractions of Costaria costata, a brown algae introduced from Japan and cultured in northern China, were studied. The fucoidan fractions were extracted, separated, and purified using a combinatorial procedure consisting of enzymolysis, ethanol precipitation, and DEAE and size-exclusion chromatographies. The fundamental characteristics of the four enriched fucoidan fractions (F1-F4), such as their sulphate content and monosaccharide composition, were investigated. FTIR and NMR spectroscopy were employed to further elucidate the structural features of the four fractions. It was found that the F1-F4 fractions all showed oxidative activity against hydroxyl radicals. The bioactive effects of the fucoidan fractions on CCl4-induced liver injury suggest their potential use as ingredients for functional foods or pharmaceuticals.
Assuntos
Tetracloreto de Carbono/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Phaeophyceae/química , Polissacarídeos/química , Polissacarídeos/farmacologia , Citoproteção/efeitos dos fármacos , Radical Hidroxila/química , Polissacarídeos/isolamento & purificaçãoRESUMO
The antioxidative activity of hydrolysate peptides from oysters (Crassostrea talienwhanensis) was investigated. After hydrolysis with subtilisin, the yields of the peptides that were soluble in trichloroacetic acid (TCA-soluble) and the antioxidant activities of the resulting hydrolysate were determined using an orthogonal design and a hydroxyl radical scavenging reaction. The hydrolysate was fractionated using Sephadex G-15 gel filtration chromatography, and the two resulting bioactive peptides were subsequently purified by RP-HPLC with a Kromasil C18 (ODS) column. The amino acid sequences were analyzed by nano-ESI-MS/MS. The critical reaction temperature, pH, hydrolysis time and enzyme-to-substrate (E/S) ratio were determined for the optimum hydrolysis with subtilisin, and the E/S ratio was found to be the most critical reaction condition. The amino acid sequences of the peptides (518 and 440 Da) were proline-valine-methionine-glycine-aspartic acid (PVMGA) and glutamine-histidine-glycine-valine (QHGV), respectively. These two novel peptides exhibited high antioxidative actions based on their hydroxyl and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activities.
Assuntos
Antioxidantes/química , Crassostrea/química , Proteínas Alimentares/química , Oligopeptídeos/química , Fragmentos de Peptídeos/química , Frutos do Mar/análise , Sequência de Aminoácidos , Animais , Antioxidantes/análise , Antioxidantes/isolamento & purificação , Antioxidantes/metabolismo , China , Cromatografia em Gel , Cromatografia Líquida de Alta Pressão , Cromatografia de Fase Reversa , Proteínas Alimentares/análise , Proteínas Alimentares/isolamento & purificação , Proteínas Alimentares/metabolismo , Suplementos Nutricionais , Sequestradores de Radicais Livres/análise , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/isolamento & purificação , Sequestradores de Radicais Livres/metabolismo , Radical Hidroxila/antagonistas & inibidores , Microquímica , Oligopeptídeos/análise , Oligopeptídeos/isolamento & purificação , Oligopeptídeos/metabolismo , Fragmentos de Peptídeos/análise , Fragmentos de Peptídeos/isolamento & purificação , Fragmentos de Peptídeos/metabolismo , Hidrolisados de Proteína/química , Hidrolisados de Proteína/metabolismo , Espectrometria de Massas por Ionização por Electrospray , Subtilisina/metabolismo , Espectrometria de Massas em TandemRESUMO
The instability of secondary metabolite production is a ubiquitous problem in plant cell culture. In order to understand the instability in plant cell culture, we investigated anthocyanin accumulation in suspension cultures of Vitis vinifera, as a model system, in our laboratory. Not only the anthocyanin contents but also its composition exhibited instability along with the long-term subculture. New methods were developed to indicate the instability of plant cell culture. Both the definition of instability coefficient (delta) and the application of factor scores were the first time in this field. To examine the effects of culture conditions on instability of anthocyanin biosynthesis, different subculture cycles and inoculum sizes had been investigated. Subculture cycle and inoculum size were both environmental cues driving the instability. Compared with subculture cycle, inoculum size was more effective in working on the instability of anthocyanin accumulation. Among all the conditions investigated in our study, (6.5 d, 2.00 g), (7 d, 2.00 g), (7.5 d, 2.00 g), (7 d, 1.60 g) and (7 d, 2.40 g), the condition of 7 d-subculture cycle together with 1.60 g-inoculum size was the best one to keep the stable production of anthocyanins.
Assuntos
Antocianinas/biossíntese , Técnicas de Cultura/métodos , Vitis/crescimento & desenvolvimento , Vitis/metabolismo , Antocianinas/química , Fatores de TempoRESUMO
A bioprocess intensification strategy that combines both elicitation and in situ absorption was developed to improve the production of taxuyunnanine c (Tc) in cell suspension cultures of Taxus chinensis. When 100 micromol/L methyl jasmonate was added as an elicitor on Day 7, the Tc content and yield increased 3.6 and 3.3 times respectively, however the cell growth was reduced by 10%-30%. Significant improvement in Tc yield was observed when an absorbent XAD-7 was added on different time of the culture period. The optimum Tc yield was achieved when 100 g/L XAD-7 was added simultaneously with 100 micromol/L methyl jasmonate on Day 7. The maximum Tc yield of 477.4 mg/L was obtained on Day 21 of the culture, being 6.3-fold of the control and 1.9-fold of the 100 micromol/L methyl jasmonate treatment alone. In the combined treatment, 94% of the Tc produced was secreted outside of the cells and absorbed on XAD-7 absorbents. The results demonstrated that the process strategy combining elicitation and in situ absorption was effective to intensify the Tc biosynthesis via elicitation with the removal of product feedback inhibition via absorption, presenting a great potential in commercial applications.
Assuntos
Acetatos/farmacologia , Técnicas de Cultura de Células/métodos , Ciclopentanos/farmacologia , Oxilipinas/farmacologia , Taxoides/metabolismo , Taxus/citologia , Absorção , Resinas Acrílicas/farmacologia , Poliestirenos/farmacologiaRESUMO
AFLP markers were used to construct the primary linkage map in a family of Mizuhopecten yessoensis. A total of 1 855 markers were generated in two parents and 52 progenies of the mapping family by using 56 AFLP primer combinations. Among the 1 855 markers, 598 were polymorphic and 354 were in agreement with the Mendelian segregating ratio of 1:1. Markers segregated according to Mendelian 1:1 ratio (P>0.05) and 23 distorted markers (0.01
Assuntos
Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Cruzamentos Genéticos , Ligação Genética , Pectinidae/genética , Animais , DNA/análise , Feminino , Genética Populacional , Japão , Masculino , Polimorfismo GenéticoRESUMO
Sponges (Porifera) are the oldest living metazoan in the world, among which most of them (Demospongia) can produce silicic skeleton from orthosilicic acid in the seawater under the natural enVironmental conditions. These biosilicic materials exhibit good mechanical and optical properties as well as good biocompatibility. During the biosilicification process of sponges, a protein, named as silicatein, plays an important role and has attracted great attention from biologist, chemists and material scientists. This mini review highlights the discovery of silicateins and its function as both an enzymatic catalyst and an organic template for biosilicification. The studies since 1999 were briefly introduced on the application of silicatein as a biocatalyst and template for synthesis of silica-based and other inorganic materials. It is expected to stimulate the interests in the related researches in China.
Assuntos
Catepsinas/química , Poríferos/enzimologia , Dióxido de Silício/metabolismo , Animais , Biocatálise , Materiais BiocompatíveisRESUMO
A bromoperoxidase from Gracilaria lemaneiformis was purified to homogeneity using a multi-step process of ammonium sulfate precipitation (AS), dialysis, and DEAE-cellulose 52 anion exchange chromatography. The bromoperoxidase activity was unstable or undetectable in crude extract solution. However, it became stable with electrophoretic purity after this multiple purification process. The anion exchange chromatography purification was a critical step in the purification process, which effectively eliminated the phycobiliprotein and smucilaginous polysaccharides. The purified bromoperoxidase was a monomeric enzyme with the relative molecular masses of 66 kD as determined by denaturing and native gradient gel electrophoresis. The optimal pH for bromoination was 6.0 and bromoperoxidase activity was stable as stored at a broad pH range of 3.0-9.0. Of a range of compounds tested, only vanadium enhanced bromoperoxidase activity. Kinetic studies for the bromination of monochlorodimedone (MCD) showed that the Km values of Br- and H2O2 are 53.5 micromol/L, 38 micromol/L respectively.
Assuntos
Gracilaria/enzimologia , Peroxidases/isolamento & purificação , Cromatografia por Troca Iônica/métodos , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , Cinética , Peroxidases/metabolismoRESUMO
To develop an integrated process of CO(2)-fixation and H(2) photoproduction by marine green microalga Platymonas subcordiformis, the impact of algal cells grown in CO(2)-supplemented air bubble column bioreactor was investigated on H(2) photoproduction regulated by carbonylcyanide m-chlorophenylhrazone. Highest cell growth (3.85 x 10(6) cells ml(-1)), starch content (0.25 +/- 0.08 mg per 10(6)cells) and hydrogen production (50 +/- 3 ml l(-1)) were achieved at 3% CO(2)-supplemented culture, which are respectively 1.4, 2.1, 1.5-fold of the air-supplemented culture. Improved H(2) production correlated well with the increase in starch accumulation. In this process, the algal cells have been recycled for stable H(2) production of 40-50 ml l(-1) over five cycles.
Assuntos
Reatores Biológicos , Dióxido de Carbono/metabolismo , Carbonil Cianeto m-Clorofenil Hidrazona/metabolismo , Clorófitas/metabolismo , Hidrogênio/metabolismo , Anaerobiose , Clorófitas/crescimento & desenvolvimento , Escuridão , Fermentação , Hidrogenase/metabolismo , Cinética , Fotossíntese , Complexo de Proteína do Fotossistema II/metabolismo , Amido/metabolismo , Fatores de TempoRESUMO
A cultivation-based approach was employed to compare the culturable actinobacterial diversity associated with five marine sponge species (Craniella australiensis, Halichondria rugosa, Reniochalina sp., Sponge sp., and Stelletta tenuis). The phylogenetic affiliation of the actinobacterial isolates was assessed by 16S rDNA-RFLP analysis. A total of 181 actinobacterial strains were isolated using five different culture media (denoted as M1-M5). The type of medium exhibited significant effects on the number of actinobacteria recovered, with the highest number of isolates on M3 (63 isolates) and the lowest on M1 (12 isolates). The genera isolated were also different, with the recovery of three genera on M2 and M3, and only a single genus on M1. The number of actinobacteria isolated from the five sponge species was significantly different, with a count of 83, 36, 30, 17, and 15 isolates from S. tenuis, H. rugosa, Sponge sp., Reniochalina sp., and C. australiensis, respectively. M3 was the best isolation medium for recovery of actinobacteria from S. tenuis, H. rugosa, and Sponge sp., while no specific medium preference was observed for the recovery of actinobacteria from Reniochalina sp., and C. australiensis. The RFLP fingerprinting of 16S rDNA genes digested with HhaI revealed six different patterns, in which 16 representative 16S rDNAs were fully sequenced. Phylogenetic analysis indicated that 12 strains belong to the group Streptomyces, three strains belong to Pseudonocardia, and one strain belongs to Nocardia. Two strains C14 (from C. australiensis) and N13 (from Sponge sp.) have only 96.26% and 96.27% similarity to earlier published sequences, and are therefore potential candidates for new species. The highest diversity of three actinobacteria genera was obtained from Sponge sp., though the number of isolates was low. Two genera of actinobacteria, Streptomyces, and Pseudonocardia, were isolated from both S. tenuis and C. australiensis. Only the genus of Streptomyces was isolated from H. rugosa and Reniochalina sp. Sponge species have been demonstrated here to vary as sources of culturable actinobacterial diversity, and the methods for sampling such diversity presented may be useful for improved sampling of such diversity.
Assuntos
Actinobacteria/classificação , Actinobacteria/crescimento & desenvolvimento , Filogenia , Poríferos/microbiologia , Actinobacteria/genética , Actinobacteria/isolamento & purificação , Animais , Variação Genética , Dados de Sequência MolecularRESUMO
The red seaweed, Gracilaria lemaneiformis growing as an aquaculture bioremediator along the coasts of Liaodong Peninsula, China, was investigated for the agar production. An eco-friendly method called agar photobleaching extraction process was developed for the benefit of workers' health and safety of the environment. The native agar (NA), alkali-modified agar (AA), chemical-bleached agar (CA) and photobleached agar (PA), which were extracted using different processes, were evaluated for their physical and chemical properties. The PA showed most desirable performances in terms of gel strength, gelling temperature, sulfate content and 3,6-anhydro-l-galactose content. Among the different processed agars, PA gel strength was 1913 g/cm2, the highest among the different processed agars, which increased 8.6% on the basis of the AA. Further we applied this new technique to extract agars from Gracilaria asiatica, and similar results were obtained with that of G. lemaneiformis. This indicates that the agar photobleaching extraction process is a feasible method for Gracilaria species and has a potential application. During the whole agar photobleaching extraction process the pigment content of G. lemaneiformis declined gradually and the TOC concentration in photobleaching solution increased along with the increase in the irradiation time. The mechanism of agar photobleaching could be elucidated by the photolysis theory.
Assuntos
Ágar/isolamento & purificação , Gracilaria/química , Alga Marinha/química , Ágar/efeitos da radiação , Biodegradação Ambiental , China , Ecossistema , Galactose/análise , Gracilaria/isolamento & purificação , Concentração de Íons de Hidrogênio , Luz , Água do Mar , Alga Marinha/isolamento & purificação , Sulfatos/análiseRESUMO
To characterize the formation of silica spicules, the dynamics of spiculogenesis of an intertidal marine sponge Hymeniacidon perlevis (Montagu 1818) (Porifera: Demospongiae) were investigated by measuring the gene expression of silicatein (the enzyme responsible for spicule silicification) and the dimensional changes of spicules during the developmental process of individual sponges and in cell cultures of primmorphs of archaeocyte-dominant cell populations. The different developmental stages of spicules were documented by time-lapse microscopy and observed by transmission electron microscopy during a 1-month culture period. During its annual life cycle, H. perlevis has four different developmental stages: dormancy, resuscitation, bloom, and decline. Field-grown individual sponge samples at different stages were collected over 7 months (March to September 2005). The dimensions of the silica spicules from these samples were microscopically measured and statistically analyzed. This analysis and the material properties of the spicules allowed them to be classified into four groups representing the different developmental stages of spiculogenesis. Silicatein expression in the bloom stage was more than 100 times higher than that in the other stages and was correlated with the spicule developmental stage. The trend of spicule formation in field-grown sponges was consistent with the trend in cell culture. A new parameter, the maturation degree (MD) of spicules (defined as the ratio of actual to theoretical silica deposition of mature spicules), was introduced to quantify spicule development. Silica spiculogenesis during H. perlevis development was delineated by comparing MD and silicatein expression.
Assuntos
Poríferos/citologia , Animais , Células Cultivadas , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Poríferos/crescimento & desenvolvimentoRESUMO
A marine unicellular green alga, Platymonas subcordiformis, was demonstrated to photobiologically produce hydrogen gas from seawater. The objective of this study was to localize and identify the hydrogenase isolated from P. subcordiformis. Adaptation in the presence of inhibitors of protein biosynthesis indicated that the hydrogenase was much more inhibited by cycloheximide than that by chloramphenicol. The result suggested that the hydrogenase isolated from P. subcordiformis is probably synthesized in cytoplasmic ribosomes. Both Western blot analysis and immunogold electron microscopy demonstrate that the P. subcordiformis hydrogenase is mainly located in the chloroplast stroma. The proteins that reacted specifically with the antibodies against the iron hydrogenase isolated from Chlamydomonas reinhardtii were concentrated by immunoprecipitation. The separated protein bands were cut out of the SDS-PAGE gel, in-gel digested by trypsin, and analyzed by Matrix-Assisted Laser Desorption Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF MS). Mascot was employed for analysis of the MALDI data using the public databases NCBInr. The hydrogenase isolated from P. subcordiformis was identified to be the Fe-hydrogenase.
Assuntos
Proteínas de Algas/metabolismo , Clorófitas/enzimologia , Hidrogenase/metabolismo , Imunoprecipitação/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Proteínas de Algas/isolamento & purificação , Biocatálise/efeitos dos fármacos , Western Blotting , Cloranfenicol/farmacologia , Cicloeximida/farmacologia , Citoplasma/enzimologia , Citoplasma/ultraestrutura , Eletroforese em Gel de Poliacrilamida , Hidrogenase/antagonistas & inibidores , Hidrogenase/isolamento & purificação , Proteínas Ferro-Enxofre/antagonistas & inibidores , Proteínas Ferro-Enxofre/isolamento & purificação , Proteínas Ferro-Enxofre/metabolismo , Cinética , Microscopia Imunoeletrônica , Inibidores da Síntese de Proteínas/farmacologiaRESUMO
This study aims to test the feasibility of introducing functional chemical groups into biogenic silica spicules by examining the effect of supplementing a silican coupler [3-(trimethoxysilyl)propyl]urea (3-TMOSPU) as silica source in the cultures of archaeocytes-dominant-cell-population (ADCP) primmorphs and explants of the marine sponge Hymeniacidon perleve. Analysis by Fourier Transform Infrared Spectroscopy (FT-IR) confirmed that the organic group in 3-TMOSPU was introduced into silica spicules. By comparing ADCP-primmorph cultures when supplemented with Na2SiO3, 3-TMOSPU supplementation showed no notable effect on the primmorphs development and cell locomotion behaviors. A decline in silicatein expression quantified by real-time RT-PCR was, however, observed during spiculogenesis. The decline was slower for the 3-TMOSPU group whereas significantly fewer spicules were formed. When sponge papillae explants were cultured, 3-TMOSPU supplementation had no negative effect on sponge growth but inhibited the growth biofouling of the diatom Nitzschia closterium. By monitoring the detectable Si concentration, it seemed that 3-TMOSPU was converted by the sponge and its conversion was related to spiculogenesis. Analysis of spicule dimensional changes indicated that the inhibition of spiculogenesis by 3-TMOSPU supplementation was less in ADCP-primmorphs culture due to lower 3-TMOSPU/detectable Si ratio in the media.
Assuntos
Catepsinas/metabolismo , Poríferos/metabolismo , Silício/metabolismo , Animais , Biomassa , Catepsinas/genética , Técnicas de Cultura de Células/métodos , Diferenciação Celular , Poríferos/citologia , Poríferos/crescimento & desenvolvimento , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Silício/administração & dosagem , Silício/química , Espectroscopia de Infravermelho com Transformada de FourierRESUMO
Marine sponges (Porifera) are the best source of marine bioactive metabolites for drug discovery and development, although the sustainable production of most sponge-derived metabolites remains a difficult task. In vitro cultivation of sponge cells in bioreactors has been proposed as a promising technology. However, no continuous cell line has as yet been developed. Archaeocytes are considered to be toti/multipotent stem cells in sponges and, when purified, may allow the development of continuous sponge cell lines. As a prerequisite, we have developed a novel four-step protocol for the purification of archaeocytes from a marine sponge, Hymeniacidon perleve: (1) differential centrifugation to separate large sponge cells including archaeocytes; (2) selective agglomeration in low-Ca(2+)/Mg(2+) artificial seawater in which living archaeocytes form small loose aggregates with some pinacocytes and collencytes; (3) differential adherence to remove anchorage-dependent pinacocytes, collencytes and other mesohyl cells; (4) Ficoll-Vrografin density gradient centrifugation to purify archaeocytes. The final purity of archaeocytes is greater than 80%. The proliferation potential of the archaeocytes has been demonstrated by high levels of BrdU incorporation, PCNA expression and telomerase activity. In 4-day primary cultures, the purified archaeocytes show a 2.5-fold increase in total cell number. This study opens an important avenue towards developing sponge cell cultures for the commercial exploitation of sponge-derived drugs.
Assuntos
Poríferos/citologia , Células-Tronco/citologia , Animais , Bromodesoxiuridina , Contagem de Células , Técnicas de Cultura de Células , Proliferação de Células , Separação Celular , Poríferos/ultraestrutura , Antígeno Nuclear de Célula em Proliferação/metabolismo , Células-Tronco/ultraestrutura , Telomerase/metabolismo , Fatores de TempoRESUMO
The instability of secondary metabolite production is a ubiquitous problem in plant cell culture. To understand the instability, the investigation of anthocyanin accumulation in suspension cultures of Vitis vinifera, as a model system, has been initiated in our laboratory. Suspension culture of a relatively homogeneous cell line E of V. vinifera, was established by long-term cell line selection by anthocyanin content differentiation. The aggregate size of E was smaller than that of other cell lines obtained by routine screening method. The variation coefficients of anthocyanin content in suspension cultures of E were 8.7% in long-term subcultures and 5% in repeated flasks, respectively. The effects of elicitor, precursor feeding and light irridiation on biomass and anthocyanin accumulation in suspension cultures of E had been investigated and the results showed that all the variation coefficients were lower than 12% and this indicated the importance of homogeneity on stable production in plant cell culture. With the combination treatment of 30micromol/L phenylalanine and 218micromol/L methyl jasmonate in the dark in suspension cultures of E, the anthocyanin content and production in suspension culture of E was 5.89-fold and 4.30-fold of the controls, respectively, and all the variation coefficients of biomass and anthocyanin accumulation were lower than those of the controls in 5 successive subcultures.
Assuntos
Antocianinas/biossíntese , Vitis/citologia , Vitis/metabolismo , Biomassa , Proliferação de Células , Luz , SuspensõesRESUMO
Embryonic stem (ES) cells hold promise either as an in vitro model recapitulating early embryonic development or as a renewable source of therapeutically useful cells. Certain aspects of the microenvironment (or niche) play critical roles in determining the fate of ES cells. Here, we reported the feasibility of using the technique of microencapsulation to study the interaction between ES cells and their tissue niche. ES cells' growth, viability, and differentiation in vitro were evaluated when they were enclosed in solid or liquefied core APA microcapsules. In comparison with those microcapsules with solid cores, the liquefied capsules provided a more suitable culture environment for the growth of ES cells. In addition, behavior of encapsulated ES cells in vivo was observed after their being implanted into mouse peritoneal cavities. In contrast to the prolonged lag phase in vitro, ES cells encapsulated grew much faster in vivo. Typical markers for the undifferentiated ES cells, such as AP, SSEA-1, and Oct-4 gene, were also tracked by immunochemistry and RT-PCR. Results showed that expression of markers remained high over 2 weeks of culture in vitro. However, decreased expression of markers was found in those samples in vivo with time passage. These findings implied that it was the combination of the intrinsic characteristics of ES cells and their microenvironment that regulated their fate. The APA-ES cells system may provide an optimal model to study the interaction between stem cells and their tissue niches.
Assuntos
Alginatos/farmacologia , Embrião de Mamíferos/citologia , Embrião de Mamíferos/efeitos dos fármacos , Modelos Biológicos , Polilisina/análogos & derivados , Células-Tronco/citologia , Células-Tronco/efeitos dos fármacos , Animais , Cápsulas , Técnicas de Cultura de Células/métodos , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/fisiologia , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Células Cultivadas , Embrião de Mamíferos/fisiologia , Camundongos , Polilisina/farmacologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células-Tronco/fisiologia , Fatores de TempoRESUMO
Embryonic stem (ES) cells are of significant interest either as an in vitro model recapitulating early embryonic development or as a renewable source of therapeutically useful cells. ES cells aggregation is important for embryoid bodies (EBs) formation and the subsequent generation of ES cell derivatives. This study was conducted to describe scalable production of EBs by the rotary cell culture system (RCCS, STLV type) and estimate the feasibility of constructing engineered cardiac tissue (ECT). In comparison with suspension culture in a Petri dish, the efficiency of the dynamic process was analyzed with respect to the yield of EB formation and their cardiomyocyte differentiation. Cardiomyocyte differentiation was evaluated by immunohistochemical analysis. After the elementary enrichment by gradient percoll, ES cell-derived cardiomyocytes were applied to construct ECT. Cell gross morphology, spatial distribution, and ultrastructure were evaluated by using histological analysis, confocal laser scanning microscopy, and transmission electron microscopy. Results showed that EB efficiencies in STLV were nearly 1.5-2.0 times higher than that of liquid suspension cultures, and cardiomyocyte differentiation of EBs progressed in a normal course after the dynamic cultivation in STLV. Additionally, the differentiated cultures could be enriched elementarily by gradient percoll. Once cast into the collagen strand, cells grew well and became more matured in Petri dishes. Synchronous contraction of the cell cluster was observed on the surface of the ECT, and cell connection was also established. It was the first report to have beating ES-derived cardiomyocytes on a 3-D collagen scaffold, which might provide a promising model for physiological and pharmacological studies and tissue replacement therapy.
Assuntos
Embrião de Mamíferos/citologia , Miócitos Cardíacos/citologia , Células-Tronco/citologia , Engenharia Tecidual/métodos , Animais , Agregação Celular/fisiologia , Técnicas de Cultura de Células/métodos , Diferenciação Celular/fisiologia , Linhagem Celular , Células Cultivadas , Estudos de Viabilidade , Camundongos , Miócitos Cardíacos/fisiologia , Miócitos Cardíacos/ultraestrutura , Esferoides Celulares/citologiaRESUMO
We demonstrated that a significant volume of H(2) gas could be photobiologically produced by a marine green alga Platymonas subcordiformis when an uncoupler of photophosphorylation, carbonyl cyanide m-chlorophenylhydrazone (CCCP), was added after 32 h of anaerobic dark incubation, whereas a negligible volume of H(2) gas was produced without CCCP. The role of CCCP in enhancing photobiological H(2) production was delineated. CCCP as an ADRY agent (agent accelerating the deactivation reactions of water-splitting enzyme system Y) rapidly inhibited the photosystem II (PSII) activity of P. subcordiformis cells, resulting in a markedly decline in the coupled oxygen evolution. The mitochondrial oxidative respiration was only slightly inactivated by CCCP, which depleted O(2) in the light. As a result, anaerobiosis during the stage of photobiological H(2) evolution was established, preventing severe O(2) inactivation of the reversible hydrogenase in P. subcordiformis. The uncoupling effect of CCCP accelerates electron transfer from water due to a disruption of the proton motive force and release of DeltapH across the thylakoid membrane and thus enhances the accessibility of electron and H(+) to hydrogenase. The electrons for hydrogen photoevolution are mainly from the photolysis of water (90%). Upon the addition of CCCP, Chl a/b ratio increased, which implies a decrease in the light-harvesting PSII antennae or an increase in PSII/PSI ratio, possibly resulting in higher efficiency of utilization of light energy. The enhancement of H(2) evolution by the addition of CCCP is mostly due to the combination of the above three mechanisms. However, the disruption of the proton gradient across the thylakoid membrane may prevent a sustained photobiological H(2) evolution due to a shortfall of ATP generation essential for the maintenance and repair functions of the cells.
Assuntos
Clorófitas/efeitos dos fármacos , Clorófitas/metabolismo , Hidrazonas/farmacologia , Hidrogênio/metabolismo , Fotossíntese/efeitos dos fármacos , Clorofila/metabolismo , Escuridão , Concentração de Íons de Hidrogênio , Luz , Oceanos e Mares , Oxigênio/metabolismo , Complexo de Proteína do Fotossistema II/metabolismoRESUMO
The low-production is a ubiquitous problem and has prevented the commercialization of secondary metabolite production in plant cell culture. In order to examine the effective approaches to improvement of secondary metabolite production in plant cell culture, the investigation of anthocyanins accumulation in suspension cultures of Vitis vinifera, as a model system, had been initiated in our laboratory. In this present research, various elicitors and the precursor of phenylalanine were used in combination to enhance the anthocyanins production in suspension cultures of Vitis vinifera. And an integrated process with the combination of elicitation, precursor feeding and light irradiation was reported for rational bioprocess design. Among the combination treatment of phenylalanine feeding and several elicitors (methyl-beta-cyclodextrin, dextran T-40, methyl jasmonate, extracts of Aspergillus niger and Fusarium orthoceras), the combination with methyl jasmonate gave the highest anthocyanins production in suspension cultures of Vitis vinifera. When compared to the controls, the anthocyanins content (CV/g, FCW) and production (CV/L) increased by 2.7-fold and 3.4-fold, respectively. The optimum time for the addition of phenylalanine and methyl jasmonate was 4 days after inoculation. Two cell lines with different anthocyanins-producing capacity responded differently to the optimum combination treatment of 30 micromol/L phenylalanine feeding, 218 micromol/L methyl jasmonate elicitation and 3000 to approximately 4000 1x light illumination. The high-and low-anthocyanins-producing cell lines of VV05 and VV06 produced the maximum of 2975 and 4090 CV/L of anthocyanins that were 2.5- and 5.2-fold of the controls, respectively.
Assuntos
Antocianinas/biossíntese , Meios de Cultura , Luz , Vitis/metabolismo , Acetatos/farmacologia , Técnicas de Cultura de Células/métodos , Células Cultivadas , Ciclopentanos/farmacologia , Oxilipinas/farmacologia , Fenilalanina/farmacologia , Vitis/citologiaRESUMO
Marine sponges are hosts of diverse bacteria that live in both intracellular and intercellular spaces of the multicellular animals. The aim of this study is to investigate the bacteria diversity inside the marine sponge cells of Hymeniacidon perleve by 16S rDNA gene sequences. To obtain pure sponge cells, a protocol has been developed in which the sponge tissues were firstly dissociated in CMFSW and cleaned several times. The purified sponge cells were subject to extraction of endocelluar bacterial DNA. The endocellular bacterial phylogenetic diversity of the marine sponge was determined by RFLP-16S rDNA sequencing of cloned DNA fragments. Thirteen of isolated 16S rDNA gene sequences were attributed to be alpha-Proteobacteria (5), gamma- Proteobacteria (5) and Planctomycetes (3). When compared to the bacterial diversity of the sponge tissues, alpha- and beta-proteobacteria are still the dominant bacteria genes, however Planctomycetes was not obtained in the sponge tissuse. These results indicated a different bacterial diversity in the sponge cells and sponge tissues.