RESUMO
The 12.4 kDa fungal immunomodulatory protein from Ganoderma microsporum (GMI) has bioactivity in vitro and in vivo. This study assessed the safety of GMI derived from engineered Pichia pastoris in Sprague-Dawley rats as a dietary supplement and food ingredient by evaluating subchronic toxicity, teratology, and mutagenicity. The oral gavage administration of 10 mL GMI at 0, 50, 75, or 100 mg GMI/kg body weight/day assayed for 91 consecutive days showed no mortality or moribundity. There were no test article-related findings in animal observations/measurements: cageside observation, detailed clinical observations, body weights, feed consumption, ophthalmic examinations, functional observation battery, clinical chemistry, hematology, coagulations, urinalysis, or terminal necropsy (gross or histopathology ï¬ndings) suggesting that GMI has no subchronic toxicity. The teratology toxicity study of pregnant female rats orally administered GMI at 0, 50, 75, or 100 mg/kg body weight/day throughout organogenesis (gestation date 6-18) showed no mortality, moribundity, and no test article-related finding to dam or fetus. GMI genotoxicity was not observed by mutagenicity studies of Salmonella typhimurium, in vitro chromosome aberrations, and an in vivo micronucleus test in mice. Overall, no observed-adverse-effect level (NOAEL) was determined for GMI based on the subchronic and teratology studies at 100 mg/kg body weight/day.
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Current chemotherapy and immunotherapy treatments followed by transurethral resection for urinary bladder urothelial carcinoma (UC) usually suffer from poor prognosis and high recurrence rate. Design and modification of current formulation with the novel adjuvants are needed. A recombinant protein derived from Ganoderma microsporum named as Ganoderma microsporum immunomodulatory protein (GMIP) was used to treat UC cells. We found GMIP elicits a dose-dependent and time-dependent anti-UC cell proliferation effect, with a half-maximal inhibition concentration (IC50 ) comparable to mitomycin C (MMC), a commonly used chemotherapy agent. After GMIP treatment, UC cells showed apoptotic phenomenon including cell cycle arrest in the G1 phase, elevated sub-G1 population, mitochondrial membrane potential loss, up-regulated p21 expression, p21 nuclear translocation, caspase activation, and PARP cleavage in a p53-independent but p21-mediated pathways. Unlike lung cancer cells, GMIP treated UC cells showed no autophagic scheme including Beclin-1, an autophagy to apoptosis switch marker, was not cleaved by caspase 3 and slight LC3B-II accumulation. Also, the classic autophagic inhibitor, chloroquine had no effect in GMIP-mediated cell death made us conclude that GMIP induced apoptosis through caspase activation but not autophagy in UC cells. Additionally, GMIP showed synergistic effects with MMC in killing UC cells and thus decreased the concentration of MMC usage to reach the comparable apoptotic effects. Our results delineate novel strategies for treatment of UC by GMIP alone or in combination with MMC application and provide a promising therapeutic cocktail for better treatment of urinary bladder urothelial carcinoma.
Assuntos
Apoptose/efeitos dos fármacos , Proteínas Fúngicas/farmacologia , Ganoderma/química , Fatores Imunológicos/farmacologia , Mitomicina/farmacologia , Neoplasias da Bexiga Urinária/tratamento farmacológico , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Proteínas de Neoplasias/biossíntese , Neoplasias da Bexiga Urinária/metabolismo , Neoplasias da Bexiga Urinária/patologiaRESUMO
Nuclear ribosomal DNA (nrDNA) sequences are widely used in the molecular classification of fungi. Previous phylogenetic studies of highly-valued traditional Chinese medicinal fungus Ophiocordyceps sinensis were mostly based on 18S and internal transcribed spacer (ITS) regions (ITS1, 5.8S and ITS2) of nrDNA. However, the disparity manifest in the low sequences identities between different O. sinensis isolates has led to argumentative hypotheses for this phenomenon, such as the "species complex" or "cryptic species" hypotheses. In the present study, four types of nrDNA (GC, AT-1, AT-2, and T) were identified using four primer pairs to amplify the nrDNA of six O. sinensis isolates. We demonstrate that each O. sinensis isolate contained two types of nrDNA, the omnipresent GC-type and a coexistent type alternating between the remaining three. This crucial discovery challenges the established notion of one type of nrDNA per species. We therefore propose that the composition of nrDNA types should be taken into consideration in studies of fungal genetics and classification.
RESUMO
Epidemiological studies show increased particulate matter (PM[Formula: see text]) particles in ambient air are correlated with increased myocardial infarctions. Given the close association of capillaries and alveoli, the dysfunction is caused when inhaled PM[Formula: see text] particles come in close proximity to capillary endothelial cells. We previously suggested that the inhalation of PM[Formula: see text] diesel exhaust particles (DEP) induces oxidative stress and upregulates the Nrf2/HO-1 pathway, inducing vascular permeability factor VEGFA secretion, which results in cell-cell adherens junction disruption and PM[Formula: see text] transmigratation into circulation. Here, we minimized the level that PM[Formula: see text] traveled in the bloodstream by pre-supplementing with a traditional Chinese medicine (TCM) Ganoderma tsugae DMSO extract (GTDE) prior to PM[Formula: see text] exposure. Our results show that PM[Formula: see text] caused alterations in enzyme activities and cellular anti-oxidant balance. We found decreased glutathione levels, a reduced cellular redox ratio, increased ROS generation and cytotoxicity in the cellular fractions. The oxidative stress caused DNA damage and apoptosis, likely causing downstream molecular events that trigger vasculature permeabilization and, eventually, cardiovascular disorders. Our results show long-term GTDE treatment increased endogenous glutathione level, while PM[Formula: see text]-reduced glutathione levels and the cellular redox ratio. GTDE was protective against the genotoxic and apoptotic effects initiated by PM[Formula: see text] oxidative stress. Vascular permeability revealed that PM[Formula: see text] only accumulated on the surface of cells after GTDE treatment; no penetration was detected. After two weeks of GTDE treatment, VEGFA secretion was significantly reduced in human umbilical vein endothelial cells (HUVEC) and endothelial cell migration was blocked. Our results suggest GTDE prevents PM[Formula: see text] transmigration into the bloodstream, and the resultant dysfunction, by inhibiting oxidative stress production and endothelial permeability.
Assuntos
Permeabilidade Capilar/efeitos dos fármacos , Ganoderma/química , Material Particulado/efeitos adversos , Extratos Vegetais/administração & dosagem , Extratos Vegetais/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Glutationa/metabolismo , Células Endoteliais da Veia Umbilical Humana , Humanos , Junções Intercelulares/metabolismo , Infarto do Miocárdio/induzido quimicamente , Oxirredução/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Material Particulado/metabolismo , Fatores de Tempo , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
Understanding the roles of the components of the multienzyme complex of the anaerobial cellulase system, acting on complex substrates, is crucial to the development of efficient cellulase systems for industrial applications such as converting lignocellulose to sugars for bioethanol production. In this study, we purified the multienzyme complex of Neocallimastix patriciarum J11 from a broth through cellulose affinity purification. The multienzyme complex is composed of at least 12 comprised proteins, based on sodium dodecyl sulfate polyacrylamide gel electrophoresis. Eight of these constituents have demonstrated ß-glucanase activity on zymogram analysis. The multienzyme complex contained scaffoldings that respond to the gathering of the cellulolytic components. The levels and subunit ratio of the multienzyme complex from N. patriciarum J11 might have been affected by their utilized carbon sources, whereas the components of the complexes were consistent. The trypsin-digested peptides of six proteins were matched to the sequences of cellulases originating from rumen fungi, based on identification through liquid chromatography/mass spectrometry, revealing that at least three types of cellulase, including one endoglucanase and two exoglucanases, could be found in the multienzyme complex of N. patriciarum J11. The cellulolytic subunits could hydrolyze synergistically on both the internal bonds and the reducing and nonreducing ends of cellulose. Based on our research, our findings are the first to depict the composition of the multienzyme complex produced by N. patriciarum J11, and this complex is composed of scaffoldin and three types of cellulase.
Assuntos
Celulases/isolamento & purificação , Proteínas Fúngicas/isolamento & purificação , Complexos Multienzimáticos/isolamento & purificação , Neocallimastix/enzimologia , Animais , Western Blotting , Búfalos/microbiologia , Celulases/genética , Celulases/metabolismo , Cromatografia em Gel , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Complexos Multienzimáticos/genética , Complexos Multienzimáticos/metabolismo , Neocallimastix/isolamento & purificação , Subunidades Proteicas , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Rúmen/microbiologia , Espectrometria de Massas em TandemRESUMO
BACKGROUND AND AIMS: Hemodynamic normality is crucial to maintaining the integrity of cerebral vessels and, therefore, preserving the cognitive functions of Alzheimer's disease patients. This study investigates the implications of the hemodynamic changes and the neuropathological diversifications of AlCl3-induced AD. METHODS: The experimental animals were 8- to 12-wk-old male Wistar rats. The rats were randomly divided into 2 groups: a control group and a (+)control group. Food intake, water intake, and weight changes were recorded daily for 22 wk. Synchronously, the regional cerebral blood flow (rCBF) of the rats with AlCl3-induced AD were measured using magnetic resonance imaging (MRI). The hemorheological parameters were analyzed using a computerized auto-rotational rheometer. The brain tissue of the subjects was analyzed using immunohistological chemical (IHC) staining to determine the beta-amyloid (Aß) levels. RESULTS: The results of hemodynamic analysis revealed that the whole blood viscosity (WBV), fibrinogen, plasma viscosity and RBC aggregation index (RAI) in (+)control were significantly higher than that of control group, while erythrocyte electrophoresis (EI) of whole blood in (+)control were significantly lower than that of control group. The results of acetylcholinesterase-RBC (AChE-RBC)in the (+)control group was significantly higher than that of the control group. The results also show that the reduction of rCBF in rats with AlCl3-induced AD was approximately 50% to 60% that of normal rats. IHC stain results show that significantly more Aß plaques accumulated in the hippocampus and cortex of the (+)control than in the control group. CONCLUSION: The results accentuate the importance of hemorheology and reinforce the specific association between hemodynamic and neuropathological changes in rats with AlCl3-induced AD. Hemorheological parameters, such as WBV and fibrinogen, and AChE-RBC were ultimately proven to be useful biomarkers of the severity and progression of AD patients. In addition, the parameters can be substituted for invasive inspection in therapeutic intervention.
Assuntos
Doença de Alzheimer/sangue , Doença de Alzheimer/patologia , Encéfalo/patologia , Encéfalo/fisiopatologia , Hemodinâmica , Cloreto de Alumínio , Compostos de Alumínio , Doença de Alzheimer/fisiopatologia , Peptídeos beta-Amiloides/metabolismo , Animais , Viscosidade Sanguínea , Encéfalo/irrigação sanguínea , Catalase/metabolismo , Córtex Cerebral/enzimologia , Córtex Cerebral/patologia , Circulação Cerebrovascular , Cloretos , Meio Ambiente , Reação de Fuga , Glutationa Peroxidase/metabolismo , Hipocampo/enzimologia , Hipocampo/patologia , Imuno-Histoquímica , Angiografia por Ressonância Magnética , Masculino , Aprendizagem em Labirinto , Memória , Neurônios/metabolismo , Neurônios/patologia , Estresse Oxidativo , Ratos Wistar , Superóxido Dismutase/metabolismo , Análise e Desempenho de TarefasRESUMO
An 1888-bp cDNA designated celA, isolated from a cDNA library of Neocallimastix patriciarum J11 was cloned. The celA had an open reading frame of 1530 bp encoding J11 CelA of 510 amino acids. The primary structure analysis of J11 CelA revealed a complete cellulose-binding domain at the N-terminal, followed by an Asn, Ala, Gly, Gln and Pro-rich linker and ending with a C-terminal glycosyl hydrolase family 6 catalytic domain. The mature J11 CelA was overexpressed in Escherichia coli and purified to homogeneity. This enzyme had high specific activities towards barley ß-glucan and lichenan, low toward carboxymethyl cellulose (CMC), Avicel, and H3PO4-swollen Avicel (PSA). The product of Avicel hydrolysis was cellobiose indicating that J11 CelA is a typical cellobiohydrolase. The recombinant J11 CelA had an optimal pH of 6.0 and was stable over a wide range of pH (5.2-11.3). The enzyme showed an optimal temperature of 50°C and was still maintained approximately 50% of the maximum activity in response to the treatment at 70°C for 1h. Cobalt and Fe(3+) at 1 mM greatly activated the enzyme activity. As a thermostable and pH stable enzyme with crystalline cellulose-degrading activity, J11 CelA is a potential candidate for the bioethanol industry.
Assuntos
Celulose 1,4-beta-Celobiosidase/química , Celulose 1,4-beta-Celobiosidase/genética , Proteínas Fúngicas/genética , Neocallimastix/enzimologia , Sequência de Aminoácidos , Carboximetilcelulose Sódica/química , Carboximetilcelulose Sódica/metabolismo , Celulose 1,4-beta-Celobiosidase/metabolismo , Clonagem Molecular , DNA Complementar/química , DNA Complementar/metabolismo , Estabilidade Enzimática , Escherichia coli/genética , Proteínas Fúngicas/química , Proteínas Fúngicas/metabolismo , Temperatura Alta , Concentração de Íons de Hidrogênio , Dados de Sequência Molecular , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismoRESUMO
Cordyceps sinensis (CS) has been commonly used as herbal medicine and a health supplement in China for over two thousand years. Although previous studies have demonstrated that CS has benefits in immunoregulation and anti-inflammation, the precise mechanism by which CS affects immunomodulation is still unclear. In this study, we exploited duplicate sets of loop-design microarray experiments to examine two different batches of CS and analyze the effects of CS on dendritic cells (DCs), in different physiology stages: naïve stage and inflammatory stage. Immature DCs were treated with CS, lipopolysaccharide (LPS), or LPS plus CS (LPS/CS) for two days, and the gene expression profiles were examined using cDNA microarrays. The results of two loop-design microarray experiments showed good intersection rates. The expression level of common genes found in both loop-design microarray experiments was consistent, and the correlation coefficients (Rs), were higher than 0.96. Through intersection analysis of microarray results, we identified 295 intersecting significantly differentially expressed (SDE) genes of the three different treatments (CS, LPS, and LPS/CS), which participated mainly in the adjustment of immune response and the regulation of cell proliferation and death. Genes regulated uniquely by CS treatment were significantly involved in the regulation of focal adhesion pathway, ECM-receptor interaction pathway, and hematopoietic cell lineage pathway. Unique LPS regulated genes were significantly involved in the regulation of Toll-like receptor signaling pathway, systemic lupus erythematosus pathway, and complement and coagulation cascades pathway. Unique LPS/CS regulated genes were significantly involved in the regulation of oxidative phosphorylation pathway. These results could provide useful information in further study of the pharmacological mechanisms of CS. This study also demonstrates that with a rigorous experimental design, the biological effects of a complex compound can be reliably studied by a complex system like cDNA microarray.
Assuntos
Cordyceps/química , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Perfilação da Expressão Gênica/métodos , Células Cultivadas , Humanos , Lipopolissacarídeos/farmacologia , Análise de Sequência com Séries de OligonucleotídeosRESUMO
Ganoderma lucidum, an oriental medicinal mushroom, has been widely used in Asia to promote health and longevity. LZ-8 is a protein derived from the fungus G. lucidum and has immunomodulatory capacities. In this study, we investigated the immune modulatory effects of rLZ-8 on human monocyte-derived DCs. Treatment of DC with rLZ-8 resulted in the enhanced cell-surface expression of CD80, CD86, CD83, and HLA-DR, as well as the enhanced production of IL-12 p40, IL-10, and IL-23, and the capacity for endocytosis was suppressed in DCs. In addition, treatment of DCs with rLZ-8 resulted in an enhanced, naïve T cell-stimulatory capacity and increased, naïve T cell secretion of IFN-gamma and IL-10. Neutralization with antibodies against TLR4 inhibited the rLZ-8-induced production of IL-12 p40 and IL-10 in DCs. rLZ-8 can stimulate TLR4 or TLR4/MD2-transfected HEK293 cells to produce IL-8. These results suggested an important role for TLR4 in signaling DCs upon incubation with rLZ-8. Further study showed that rLZ-8 was able to augment IKK, NF-kappaB activity, and also IkappaBalpha and MAPK phosphorylation. Further, inhibition of NF-kappaB by helenalin prevented the effects of rLZ-8 in the expression of CD80, CD86, CD83, and HLA-DR and production of IL-12 p40 and IL-10 in various degrees. To confirm the in vitro data, we investigated the effect of rLZ-8 further on antigen-specific antibody and cytokine production in BALB/c mice. Immunization with OVA/rLZ-8 showed that the anti-OVA IgG2a, IFN-gamma, and IL-2 were increased significantly compared with OVA alone in BALB/c mice. In conclusion, our experiments demonstrated that rLZ-8 can effectively promote the activation and maturation of immature DCs, preferring a Th1 response, suggesting that rLZ-8 may possess a potential effect in regulating immune responses.
Assuntos
Células Dendríticas/metabolismo , Proteínas Fúngicas/farmacologia , Fatores Imunológicos/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Monócitos/metabolismo , NF-kappa B/metabolismo , Animais , Antígenos CD/biossíntese , Citocinas/biossíntese , Citocinas/imunologia , Células Dendríticas/citologia , Células Dendríticas/imunologia , Proteínas Fúngicas/química , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/imunologia , Antígenos HLA-DR/biossíntese , Antígenos HLA-DR/imunologia , Humanos , Imunoglobulina G/imunologia , Imunoglobulina G/farmacologia , Fatores Imunológicos/química , Sistema de Sinalização das MAP Quinases/fisiologia , Camundongos , Camundongos Endogâmicos BALB C , Monócitos/citologia , Monócitos/imunologia , NF-kappa B/imunologia , Reishi/química , Células Th1/citologia , Células Th1/imunologia , Células Th1/metabolismo , Receptor 4 Toll-Like/antagonistas & inibidores , Receptor 4 Toll-Like/imunologia , Receptor 4 Toll-Like/metabolismoRESUMO
Cordyceps sinensis (CS), a Chinese tonifying herb, has been widely used for centuries in Asian countries as a medicine and a health supplement. Although ample evidence indicates that CS can modulate immune responses, the functional effect of CS on dendritic cells (DCs) is still unclear. This study examines how CS affects human monocyte-derived DCs in two physiological states: naïve and LPS-induced inflammatory. Our experimental results demonstrate that CS acts as an activator and maturation inducer of immature DCs by stimulating the expression of costimulatory molecules and proinflammatory cytokines by DCs, enhancing the DC-induced, allogeneic T cell proliferation, and reducing the endocytic ability of DCs. In contrast, CS suppresses the LPS-induced, inflammatory response by decreasing the LPS-induced expression of costimulatory molecules and proinflammatory cytokines by DCs. CS also suppresses the LPS-induced, DC-elicited, allogeneic T cell proliferation and shifts the LPS-activated, DC-driven Th1 response toward a Th2 response. These results demonstrate that CS differentially regulates the DC activities according to the presence or absence of the inflammatory signs. Restated, with the lack of an ongoing inflammatory environment, CS primes DCs toward a Th1-type immunity, whereas in a potential inflammatory reaction, CS balances the over-reactivity of elicited Th1 immunity. This investigation illustrates the Yin-Yang balancing effects of CS as a medicine and a health supplement.
Assuntos
Cordyceps/metabolismo , Células Dendríticas/citologia , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/imunologia , Humanos , Interleucina-12/biossíntese , Interleucina-1beta/biossíntese , Interleucina-6/biossíntese , Lipopolissacarídeos/farmacologia , Fenótipo , Células Th1/citologia , Células Th1/efeitos dos fármacos , Células Th1/imunologia , Células Th2/citologia , Células Th2/efeitos dos fármacos , Células Th2/imunologia , Fator de Necrose Tumoral alfa/biossínteseRESUMO
Ganoderma lucidum, a medicinal fungus is thought to possess and enhance a variety of human immune functions. An immuno-modulatory protein, Ling Zhi-8 (LZ-8) isolated from G. lucidum exhibited potent mitogenic effects upon human peripheral blood lymphocytes (PBL). However, LZ-8-mediated signal transduction in the regulation of interleukin-2 (IL-2) gene expression within human T cells is largely unknown. Here we cloned the LZ-8 gene of G. lucidum, and expressed the recombinant LZ-8 protein (rLZ-8) by means of a yeast Pichia pastoris protein expression system. We found that rLZ-8 induces IL-2 gene expression via the Src-family protein tyrosine kinase (PTK), via reactive oxygen species (ROS), and differential protein kinase-dependent pathways within human primary T cells and cultured Jurkat T cells. In essence, we have established the nature of the rLZ-8-mediated signal-transduction pathways, such as PTK/protein kinase C (PKC)/ROS, PTK/PLC/PKCalpha/ERK1/2, and PTK/PLC/PKCalpha/p38 pathways in the regulation of IL-2 gene expression within human T cells. Our current results of analyzing rLZ-8-mediated signal transduction in T cells might provide a potential application for rLZ-8 as a pharmacological immune-modulating agent.
Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Fatores Imunológicos/farmacologia , Interleucina-2/genética , Proteína Quinase C/metabolismo , Reishi/imunologia , Transdução de Sinais/efeitos dos fármacos , Linfócitos T/efeitos dos fármacos , Complexo CD3/metabolismo , Sinalização do Cálcio/efeitos dos fármacos , Células Cultivadas , Proteínas Fúngicas/imunologia , Proteínas Fúngicas/farmacologia , Humanos , Fatores Imunológicos/imunologia , Interleucina-2/metabolismo , Isoenzimas/metabolismo , Células Jurkat , Ativação Linfocitária/efeitos dos fármacos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fosforilação/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Receptores de Antígenos de Linfócitos T/metabolismo , Proteínas Recombinantes/farmacologia , Reishi/química , Linfócitos T/enzimologia , Linfócitos T/metabolismo , Fatores de Tempo , Fosfolipases Tipo C/metabolismo , Quinases da Família src/metabolismoRESUMO
Two xylanase genes were cloned from the anaerobic fungus Neocallimastix frontalis. Xyn11A had a modular structure of two catalytic domains and two dockerin domains, while Xyn11B had one catalytic domain and two dockerin domains. The characteristics of the xylanases with and without dockerin domains were investigated. The deletion of dockerin domains had little influence on the optimal pH of xylanases, while it significantly affected the optimal temperatures. The optimal temperatures increased from 55 to 60 degrees C for Xyn11A and 60 to 65 degrees C for Xyn11B after the deletion of dockerin domains. The increase of optimal temperatures was attributed to the lower stability of the second structure in full length xylanase than that in the truncated one as evidenced by the circular dichroism spectroscopy. The specific activity of Xyn11A and Xyn11B increased about 64% and 330%, respectively, after the deletion of the dockerin domains. The removal of dockerin domains appeared to increase the overall efficiency of Xyn11A' (1.2-) and Xyn11B' (2.9-) fold with oat spelts xylan as reflected by the values of k(cat)/K(m). The results suggest that the dockerin domain might play an important role in the characteristics of xylanases from anaerobic fungi.
Assuntos
Endo-1,4-beta-Xilanases/química , Regulação Fúngica da Expressão Gênica , Neocallimastix/enzimologia , Xilanos/metabolismo , Xilosidases/química , beta-Glucosidase/química , Sequência de Aminoácidos , Dicroísmo Circular , Endo-1,4-beta-Xilanases/genética , Endo-1,4-beta-Xilanases/metabolismo , Concentração de Íons de Hidrogênio , Dados de Sequência Molecular , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Deleção de Sequência , Especificidade por Substrato , Temperatura , Xilosidases/genética , Xilosidases/metabolismo , beta-Glucosidase/genética , beta-Glucosidase/metabolismoRESUMO
The genetic similarity of different generations of Neocallimastix frontalis SK was examined by random amplified polymorphic DNA (RAPD) profiling and internal transcribed spacer 1 (ITS1) sequence analysis. N. frontalis SK was subcultured every 2-4 days, and SK-1, SK-3M, and SK-1Y represented N. frontalis SK cultures after one subculture, 50 subcultures, and 150 subcultures. The DNA polymorphisms of the different N. frontalis SK generations were compared by RAPD profiling. The RAPD results gave the same patterns for SK-1, SK-3M and SK-1Y using 12 selected random primers. The partial 18S rDNA, 5.8S rDNA, and ITS1 regions of different generations of N. frontalis SK were amplified and sequenced. The results of alignment and pairwise similarity indicated that the analyzed rRNA sequences of SK-1, SK-3M and SK-1Y were totally identical. This study thus demonstrated genetically identical DNA polymorphisms by RAPD profiling and an unvaried ITS1 region for N. frontalis SK when the strain is subcultured frequently. This suggests that this strain is homokaryotic and grows via an asexual life cycle in vitro.