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Genetic studies of Psammolestes tertius (Hemiptera : Reduviidae : Triatominae) using male genital morphology, morphometry, isoenzymes, and random amplified polymorphic DNA

Soares, RPP; Barbosa, S. E.; Borges, E. C.; Melo, T. A.; Romanha, A. J.; Dujardin, J. P.; Schofield, C. J.; Diotaiuti, L.
Fonte: Springer Publicador: Springer
Tipo: Artigo de Revista Científica Formato: 1-13
ENG
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Two Brazilian populations of Psammolestes tertius (Ceara and Minas Gerais) collected from thornbird nests (Furnariidae) were compared by male genital morphology, morphametry, isoenzymes, and random amplified polymorphic DNA (RAPD). Merle genitalia showed no difference between the populations. In contrast, morphometry, isoenzyme, and RAPD clearly distinguished the two populations. Possible mechanisms of dispersal and the origin of Psammolestes are discussed.

Invited review Giardia duodenalis: Inter-strain variability of proteins, antigens, proteases, isoenzymes and nucleic acids

Guimarães, Semiramis; Sogayar, Maria Inês Lerne; Franco, Marcello F. de
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 45-58
ENG
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Giardia duodenalis isolates from asymptomatic or symptomatic patients and from animals present similarities and differences in the protein composition, antigenic profile, pattern of proteases and isoenzymes, as well as in nucleic acids analysis. In the present overview, these differences and similarities are reviewed with emphasis in the host-parasite interplay and possible mechanisms of virulence of the protozoon.

Giardia duodenalis: INTER-STRAIN VARIABILITY OF PROTEINS, ANTIGENS, PROTEASES, ISOENZYMES AND NUCLEIC ACIDS

GUIMARÃES,Semiramis; SOGAYAR,Maria Inês Leme; FRANCO,Marcello F. de
Fonte: Instituto de Medicina Tropical Publicador: Instituto de Medicina Tropical
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/1999 EN
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Giardia duodenalis isolates from asymptomatic or symptomatic patients and from animals present similarities and differences in the protein composition, antigenic profile, pattern of proteases and isoenzymes, as well as in nucleic acids analysis. In the present overview, these differences and similarities are reviewed with emphasis in the host-parasite interplay and possible mechanisms of virulence of the protozoon.

Lactate dehydrogenase isoenzymes in dental pulp of rats according to stage of root development

Losso,Estela Maris; Nicolau,José
Fonte: Fundação Odontológica de Ribeirão Preto Publicador: Fundação Odontológica de Ribeirão Preto
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2003 EN
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The objective of this study was to present a classification of the root development stage of female rat molar teeth and to evaluate the variation in the lactate dehydrogenase (LDH) activity and electrophoretic isoenzyme profile according to the stage of root development of the molar teeth. We also studied the LDH activity and isoenzymes of the pulp of incisor teeth. The stage of development of the rat first molar at the age of 15 days and that of the second molar at the age of 18 days was classified as the beginning of root formation. At the age of 15 days, the electrophoretic profile of the isoenzymes for the first molar showed a prevalence of LDH-1 followed by LDH-2. However, for the maxillary second molar there was a prevalence of LDH-4 followed by LDH-1, while for the mandibular second molar LDH-1 predominated followed by LDH-2 and LDH-4. From 18 days of age, the prevalence was always of LDH-1. The electrophoretic profile of LDH isoenzymes from the pulp of the incisor teeth at the ages studied (25 and 60 days) showed the following order of prevalence: LDH-1 > LDH-2 > LDH-3 > LDH-4 > LDH-5. These results suggest that there are variations in the prevalence of the various forms of LDH isoenzymes in the dental pulp of rats according to the developmental stage of the root.

Characterization and physiological roles of membrane-bound hydrogenase isoenzymes from Salmonella typhimurium.

Sawers, R G; Jamieson, D J; Higgins, C F; Boxer, D H
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /10/1986 EN
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We found that Salmonella typhimurium strain LT2 (Z) possessed two immunologically distinct, membrane-bound hydrogenase isoenzymes, which were similar in electrophoretic mobilities and apoprotein contents to hydrogenase isoenzymes 1 and 2 of Escherichia coli. The S. typhimurium enzymes cross-reacted with antibodies raised to the respective hydrogenase isoenzymes of E. coli. As for E. coli, an additional membrane-bound hydrogenase activity (termed hydrogenase 3), which did not cross-react with antibodies raised against either hydrogenase 1 or 2, was also present in detergent-dispersed membrane preparations. The physiological role of each of the three isoenzymes in E. coli has remained unclear owing to the lack of mutants specifically defective for individual isoenzymes. However, analysis of two additional wild-type isolates of S. typhimurium revealed specific defects in their hydrogenase isoenzyme contents. S. typhimurium LT2 (A) lacked isoenzyme 2 but possessed normal levels of hydrogenases 1 and 3. S. typhimurium LT7 lacked both isoenzymes 1 and 2 but retained normal hydrogenase 3 activity. Characterization of hydrogen metabolism by these hydrogenase-defective isolates allowed us to identify the physiological role of each of the three isoenzymes. Hydrogenase 3 activity correlated closely with formate hydrogenlyase-dependent hydrogen evolution...

Activation of purified human protein kinase C alpha and beta I isoenzymes in vitro by Ca2+, phosphatidylinositol and phosphatidylinositol 4,5-bisphosphate.

Kochs, G; Hummel, R; Fiebich, B; Sarre, T F; Marmé, D; Hug, H
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 15/04/1993 EN
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The increasing number of eukaryotic protein kinase C (PKC) isoenzymes which have been described has raised great interest in potential differences in the cellular expression, the mode of activation and the substrate specificity of these isoenzymes. The last two aspects have mostly been studied with isoenzymes purified from rat or bovine brain or from recombinant-baculovirus-infected insect cells. In this study, we have expressed the human PKC isoenzymes alpha and beta I in recombinant-baculovirus-infected insect cells. The isoenzymes were purified to homogeneity by a four-step procedure which included a reversible Ca(2+)-dependent association/dissociation to and from the endogenous membranes of the lysed insect cells. Characterization of the purified enzymes with respect to ATP requirement and substrate specificity, using the epidermal-growth-factor receptor peptide and histone III-S respectively, revealed no isoenzyme-specific differences. Activation by trypsin or Ca2+ and a variety of different phospholipids and phosphoinositides (in a mixed-micellar assay) gave the following results. Proteolytic cleavage of the PKC isoenzymes by trypsin generated fully activated phospholipid-independent PKC beta I, whereas PKC alpha reached only 50% of the activity obtained in the presence of phospholipids. PKC alpha and beta I showed no difference in their dependence on Ca2+...

Isoenzymes of phosphofructokinase in the rat. Demonstration of the three non-identical subunits by biochemical, immunochemical and kinetic studies.

Vora, S; Oskam, R; Staal, G E
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 15/07/1985 EN
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In man and the rabbit, 6-phosphofructokinase (PFK, EC 2.7.1.11) exists in tetrameric isoenzymic forms composed of muscle (M or A), liver (L or B) and platelet or brain (P or C) subunits, which are under separate genetic control. In contrast, the genetic control of the rat PFK has not yet been conclusively established; it is unclear whether the P-type or C-type subunit exists in this species. To resolve this question, we investigated the enzyme from the skeletal muscle, liver and brain of rats of Wag/Rij strain. Our studies demonstrate that the rat PFK is also under the control of three structural loci and that the homotetramers M4, P4 and L4 exhibit unique chromatographic, immunological and kinetic-regulatory properties. Skeletal-muscle and brain PFKs consist of isolated M4 and P4 homotetramers respectively. Although liver PFK consists predominantly of L4 homotetramer, it also contains small amounts of PL3 and P2L2 species. All three PFKs exhibit allosteric properties: co-operativity with fructose 6-phosphate and inhibition by ATP decrease in the order P4 greater than L4 greater than M4. P4 and M4 tetramers are the most sensitive to citrate inhibition, whereas L4 tetramer is the least sensitive. More importantly, P4 and L4 isoenzymes are the most sensitive to activation by fructose 2...

Analysis of the phosphofructokinase subunits and isoenzymes in human tissues.

Dunaway, G A; Kasten, T P; Sebo, T; Trapp, R
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 01/05/1988 EN
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The 6-phosphofructo-1-kinase (PFK) subunits and isoenzymes were studied in human muscle, heart, brain, liver, platelets, fibroblasts, erythrocytes, placenta and umbilical cord. In each tissue, the subunit types in the native isoenzymes were characterized by immunological titration with subunit-specific antibodies and by column chromatography on QAE (quaternary aminoethyl)-Sephadex. Further, the subunits of the partially purified native isoenzymes were resolved by SDS/polyacrylamide-gel electrophoresis, identified by immunoblotting, and quantified by scanning gel densitometry of silver-stained gels and immunoblots. Depending on the type of tissue, one to three subunits were detected. The Mr values of the L, M and C subunits regardless of tissue were 76,700 +/- 1400, 82,500 +/- 1640 and 86,500 +/- 1620. Of the tissues studied, only the muscle PFK isoenzymes exhibited one subunit, which was the M-type subunit. Of the other tissues studied, the PFK isoenzymes contained various amounts of all three subunits. Considering the properties of the native PFK isoenzymes, it is clear that, in human tissues, they are not simply various combinations of two or three homotetrameric isoenzymes, but complex mixtures of homotetramers and heterotetramers. The kinetic/regulatory properties of the various isoenzyme pools were found to be dependent on subunit composition.

Carbonic anhydrase isoenzymes in the erythrocytes and uterus of the rabbit

McIntosh, J. E. A.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /11/1970 EN
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1. Two forms of the zinc-containing enzyme carbonic anhydrase (EC 4.2.1.1) were isolated from rabbit erythrocytes and two forms from rabbit uterine tissue (endometrium) in the progestational stage of pregnancy (days 6–8 of gestation). Separation of the isoenzymes was achieved by ion-exchange chromatography, preparative polyacrylamide-gel electrophoresis and isoelectric focusing. A comparison was made of the general properties and kinetic behaviour of the purified isoenzymes. 2. Although indistinguishable in terms of molecular weight and zinc content the isoenzymes were very different as catalysts of the hydration of carbon dioxide. The two erythrocyte isoenzymes, found in almost equal amounts, differed more than 100-fold in specific activity. Of the two isoenzymes prepared from either endometrial or entire uterine homogenates one was kinetically indistinguishable from the erythrocyte high-activity form, whereas the other, also possessing high activity, was found only in the endometrial or uterine tissue. Present evidence suggests that the former isoenzyme originated from residual blood contaminating the tissue homogenates, and that a marked rise in the content of the latter isoenzyme accounts for the increase in rabbit endometrial carbonic anhydrase activity that previously has been observed in early pregnancy. 3. Minor forms of the erythrocyte isoenzymes...

Carbonic anhydrase isoenzymes in the erthrocytes and dorsolateral prostate of the rat

McIntosh, J. E. A.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /09/1969 EN
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1. Three forms of the zinc-containing enzyme carbonic anhydrase (EC 4.2.1.1) were isolated from the erythrocytes of the rat and two forms from the dorsolateral prostate of the rat. Several additional minor components were observed but not isolated. Separation of the isoenzymes was achieved by ion-exchange chromatography, polyacrylamide-gel electrophoresis and isoelectric focusing. 2. The general properties of the isolated isoenzymes, their molecular weights and their contents of zinc were closely similar. As catalysts of the hydration of carbon dioxide, however, they were distinctly different. The two most abundant isoenzymes of the erythrocytes, which were found in equal proportions, differed 70-fold in specific activity, whereas the isoenzymes of the dorsolateral prostate were similar to one another and resembled the high-activity component of the erythrocytes. The inhibition of the latter by acetazolamide (5-acetamido-1-thia-3,4-diazole-2-sulphonamide) was mainly competitive, whereas in identical conditions the low-activity erythrocyte component and the dorsolateral prostate isoenzymes were non-competitively inhibited. 3. The use of chloroform–ethanol to remove haemoglobin from the rat haemolysate was found (a) to bring about changes in the kinetic properties of the soluble isoenzymes and (b) to cause the appearance of an additional isoenzyme. 4. The actions were compared of the inhibitors acetazolamide...

Differentiation characteristics of cholesteatoma epithelium determined by expression of transglutaminase isoenzymes.

Chang, C. S.; Jun, B. H.; Song, K. Y.; Kim, I. G.
Fonte: Korean Academy of Medical Sciences Publicador: Korean Academy of Medical Sciences
Tipo: Artigo de Revista Científica
Publicado em /12/1999 EN
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Transglutaminase (TGase) isoenzymes are involved in the process of the differentiation and cornification of keratinocytes in the epidermis. This study investigates the presence and localization of three TGase isoenzymes to elucidate the nature and differentiation status of the squamous epithelium in human aural cholesteatoma. Twenty cholesteatoma specimens were used. The presence and localization of three TGase isoenzymes were studied by reverse transcription-polymerase chain reaction (RT-PCR) and immunohistochemistry. mRNA expression of three TGase isoenzymes were detected in the tested cholesteatomas with variable levels. The immunohistochemical staining patterns of three TGase isoenzymes showed variations within specimens, relating to keratinizing activity. TGase K is the most abundant among three isoenzymes. Keratinizing epithelium of cholesteatoma have similar expression profiles of TGase isoenzymes with those of epidermis of the skin. Other areas, particularly those showing non-keratinizing epithelium, showed weak immunostaining of TGase E and C, suggesting its different maturation status from keratinizing epithelium. The results of this study indicate that epithelium of cholesteatoma undergoes same direction of maturation and differentiation characteristics as the epidermis of skin...

Separation of serum LD isoenzymes by capillary electrophoresis

Uji, Yoshinori; Okabe, Hiroaki
Fonte: Springer India Publicador: Springer India
Tipo: Artigo de Revista Científica
Publicado em /07/2001 EN
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Separation and quantitative estimation of the isoenzymes of lactate dehydrogenase(LD) in serum were accomplished with capillary electrophoresis system. An uncoated fused silica capillary column 50 cm long, 75μm I.D. and substrate containing running buffer including L-lactic acid and NAD+ were used for the separation of serum LD isoenzymes. The resulting product of “NADH” was detected at 340 nm. Injection of 10 nL of five fold diluted serum sample were performed by pressure injection within 2 seconds. The isoenzymes were separated at 10 kV of voltage for 5 min, by turning off the voltage applied for 30 min incubation at 24°C for reaction between substrate and isoenzymes, and applying voltage of 30 min. Under these conditions, the isoenzymes of LD were detected by a NADH generated as isoenzyme of LD-5 emerged at 20 min, LD-1 peak at 23.5 min with close to baseline separation of the other isoenzymes which emerge between LD-5 to LD-1, after the emergence to LD-1 peak, followed another peak, termed “sample shock”: The results obtained by the proposed method correlated well with those by gel electrophoresis systemes (r=0.92∼0.98) for each five LD isoenzymes, respectively. Within-run precision CVs for 5 replicate analysis were 3.01 (LD-3...

The Activity of Alcohol Dehydrogenase (ADH) Isoenzymes and Aldehyde Dehydrogenase (ALDH) in the Sera of Patients with Brain Cancer

Jelski, Wojciech; Laniewska-Dunaj, Magdalena; Orywal, Karolina; Kochanowicz, Jan; Rutkowski, Robert; Szmitkowski, Maciej
Fonte: Springer US Publicador: Springer US
Tipo: Artigo de Revista Científica
EN
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Human brain tissue contains various alcohol dehydrogenase (ADH) isoenzymes and possess also aldehyde dehydrogenase (ALDH) activity. In our last experiments we have shown that ADH and ALDH are present also in the brain tumour cells. Moreover the activities of total ADH and class I isoenzymes were significantly higher in cancer tissue than healthy cells. It can suggests that these changes may be reflected by enzyme activity in the serum of patients with brain cancer. Serum samples were taken for routine biochemical investigation from 62 patients suffering from brain cancer (36 glioblastoma, 26 meningioma). For the measurement of the activity of class I and II ADH isoenzymes and ALDH activity, the fluorometric methods were used. The total ADH activity and activity of class III and IV isoenzymes were measured by the photometric method. A statistically significant increase of class I alcohol dehydrogenase isoenzymes was found in the sera of patients with brain cancer. The median activity of this class isoenzyme in the patients group increased about 24 % in the comparison to the control level. The total alcohol dehydrogenase activity was also significantly higher (26 %) among patients with brain tumour than healthy ones. The activities of other tested ADH isoenzymes and total ALDH were unchanged. The increase of the activity of total ADH and class I alcohol dehydrogenase isoenzyme in the sera of patients with brain cancer seems to be caused by the release of this isoenzyme from tumour’s cells.

Effects of the antiandrogen flutamide on the expression of protein kinase C isoenzymes in LNCaP and PC3 human prostate cancer cells

Montalvo Zenarruzabeitia, Leire; Carmena Sierra, María José; Bolaños, Oscar; Rodríguez Henche, Nieves; Sánchez Chapado, Manuel; Prieto Villapún, Juan Carlos
Fonte: Portland Press Publicador: Portland Press
Tipo: Artigo de Revista Científica Formato: application/pdf
ENG
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Flutamide is a nonsteroidal antiandrogen that is frequently used for total androgen blockage in the treatment of advanced prostate cancer. We investigated the effect of this antiandrogen on the expression of protein kinase C (PKC) isoenzymes (a, b1, e, f) that are involved in cell growth, apoptosis and neoplastic transformation. Androgen-dependent (LNCaP) and independent (PC3) human prostate cancer cells were cultured in a medium that contained fetal bovine serum (FBS) or charcoal-stripped serum (CSS) and treated with 10 lM flutamide. The expression of PKC isoenzymes and the androgen receptor (AR) were analyzed by Western blot and RT-PCR, respectively. Serum steroids differentially regulate the expression of PKC isoenzymes in LNCaP and PC3 cells. Flutamide up-regulated the expression of a, b1 and f, but not e, PKC isoenzymes in CSS-LNCaP cells. These results were not homogeneously reproduced in the presence of androgens. We observed an opposite effect of flutamide, compared to CSS, on PKCb1 isoform expression in CSS-LNCaP suggesting that this antiandrogen exerts an agonistic effect. In PC3 cells flutamide potentiated the expression of the four PKC isoenzymes in almost all conditions tested (FBS- and CSScultured cells). Such effect of flutamide in PC3 cells is independent of AR since no expression of AR was detected. These results provide new evidence on antagonistic/agonistic responses of prostate cancer cells to antiandrogen drugs that are widely used in therapy and show that flutamide can elicit responses in prostate cancer cells that do not express AR.

Molecular weight estimation of esterase isoenzymes in closely related Drosophila Species (Diptera: Drosophilidae) in non-denaturing polyacrylamide gel electrophoresis

MATEUS, Rogério Pincela; CABRAL, Hamilton; BONILLA-RODRIGUEZ, Gustavo Orlando; CERON, Carlos Roberto
Fonte: Tecpar Publicador: Tecpar
Tipo: Artigo de Revista Científica
ENG
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36.88%
A method that allows the measure of molecular weight of two well-known and closely related esterases from Drosophila mojavensis and its sibling species, D. arizonae, is here described, using native polyacrylamide gel electrophoresis at several concentrations, applying Fergunson´s principles. These enzymes, namely EST-4 and EST-5, presented molecular weight values between 81 and 91 kDa. In spite of their distinct expression pattern through the insect's life cycle, they showed properties of isoenzymes codified by distinct structural genes, supporting the hypothesis of a rather recent gene duplication event that generated both in D. mojavensis and D. arizonae, as well as in other species of repleta group. The method is simple and adequate to be applied to preliminary molecular weight determination of other enzymes without any previous purification procedure.; Neste trabalho, um método que permite a estimativa do peso molecular de duas esterases conhecidas e intimamente relacionadas, encontradas em Drosophila mojavensis e sua espécie aparentada D. arizonae, é descrito. Este método é realizado utilizando a técnica de eletroforese em diferentes concentrações de gel e aplicando os princípios de Fergunson. As enzimas, denominadas EST-4 e EST-5...

Alternatively spliced mRNA variants of chloroplast ascorbate peroxidase isoenzymes in spinach leaves.

Yoshimura, K; Yabuta, Y; Tamoi, M; Ishikawa, T; Shigeoka, S
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 15/02/1999 EN
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We have previously shown that stromal and thylakoid-bound ascorbate peroxidase (APX) isoenzymes of spinach chloroplasts arise from a common pre-mRNA by alternative splicing in the C-terminus of the isoenzymes [Ishikawa, Yoshimura, Tamoi, Takeda and Shigeoka (1997) Biochem. J. 328, 795-800]. To explore the production of mature, functional mRNA encoding chloroplast APX isoenzymes, reverse transcriptase-mediated PCR and S1 nuclease protection analysis were performed with poly(A)+ RNA or polysomal RNA from spinach leaves. As a result, four mRNA variants, one form of thylakoid-bound APX (tAPX-I) and three forms of stromal APX (sAPX-I, sAPX-II and sAPX-III), were identified. The sAPX-I and sAPX-III mRNA species were generated through the excision of intron 11; they encoded the previously identified sAPX protein. Interestingly, the sAPX-II mRNA was generated by the insertion of intron 11 between exons 11 and 12. The use of this insertional sequence was in frame with the coding sequence and would lead to the production of a novel isoenzyme containing a C-terminus in which a seven-residue sequence replaced the last residue of the previously identified sAPX. The recombinant novel enzyme expressed in Escherichia coli showed the same enzymic properties (except for molecular mass) as the recombinant sAPX from the previously identified sAPX-I mRNA...

Molecular weight estimation of esterase isoenzymes in closely related Drosophila Species (Diptera: Drosophilidae) in non-denaturing polyacrylamide gel electrophoresis

Mateus,Rogério Pincela; Cabral,Hamilton; Bonilla-Rodriguez,Gustavo Orlando; Ceron,Carlos Roberto
Fonte: Instituto de Tecnologia do Paraná - Tecpar Publicador: Instituto de Tecnologia do Paraná - Tecpar
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/10/2009 EN
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36.88%
A method that allows the measure of molecular weight of two well-known and closely related esterases from Drosophila mojavensis and its sibling species, D. arizonae, is here described, using native polyacrylamide gel electrophoresis at several concentrations, applying Fergunson´s principles. These enzymes, namely EST-4 and EST-5, presented molecular weight values between 81 and 91 kDa. In spite of their distinct expression pattern through the insect's life cycle, they showed properties of isoenzymes codified by distinct structural genes, supporting the hypothesis of a rather recent gene duplication event that generated both in D. mojavensis and D. arizonae, as well as in other species of repleta group. The method is simple and adequate to be applied to preliminary molecular weight determination of other enzymes without any previous purification procedure.

Influence of Culture Conditions on Laccase Production, Growth, and Isoenzymes Patterns in Native White Rot Fungi from the Misiones Rainforest (Argentina)

Fonseca, Maria Isabel; Fariña, Julia Inés; Sanabria, Irma Lorena; Villalba, Laura; Zapata, Pedro Dario
Fonte: North Carolina State University. Department of Wood and Paper Science Publicador: North Carolina State University. Department of Wood and Paper Science
Tipo: info:eu-repo/semantics/article; info:ar-repo/semantics/artículo; info:eu-repo/semantics/publishedVersion Formato: application/pdf
ENG
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Many biotechnological processes pursuing sustainability search effective, inexpensive and environmentally friendly alternatives to replace conventional practices. Lignocellulolytic white rot fungi can serve for this task through their enzymatic system including laccase (Lac). One of purposes of biotechnological enzymes production processes is usually to find the best growing and secretion conditions for a particularly selected fungus. In this work, different fungi isolated from the Misiones rainforest (Coriolus versicolor f. antarcticus BAFC-266, Ganoderma applanatum strain F, Phlebia brevispora BAFC-633 and Pycnoporus sanguineus BAFC-2126) were incubated at different temperatures (25, 29, 33°C) and pHs (3.5, 4.5, 5.5) under static conditions for 7, 10 and 14 days to evaluate their growing ability and Lac production. Results revealed specific favorable conditions for growth and protein secretion depending on the fungus under consideration, making necessary to adjust these parameters for each particular case. The combined effect of these cultivation parameters showed a marked influence on the secreted Lac activity by P. brevispora BAFC 633, with the highest activity (~ 240 U/l) at 29ºC and pH 4.5 at the 10th day of cultivation. The presence of Lac isoenzymes also depended on the pH...

PROPERTIES OF LACCASE ISOENZYMES PRODUCED BY THE BASIDIOMYCETE CERIPORIOPSIS-SUBVERMISPORA

Cullen, D.; Vicuña E., Rafael; Lobos, S.; Salas, Loreto; Larraín, Juan; Salas, Carlos
Fonte: PORTLAND PRESS Publicador: PORTLAND PRESS
Tipo: Artículo de revista
EN
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Artículo de publicación ISI; Laccase is one of the ligninolytic enzymes found in liquid cultures of the fungus Ceriporiopsis subvermispora in defined medium. As an approach to a clarification of the role of laccases during the attack on lignin by the fungus, the enzyme has been characterized further. The levels of this phenol oxidase increase 2-fold in the presence of p-anisidine and are severely affected when addition of either Mn(II) or Cu(II) ions to the medium is omitted. Isoelectrofocusing allowed the resolution of two laccase isoenzymes, with pIs of 3.65 and 3.59. In rich medium, laccase activity is 10-fold higher than in salt medium, and it is not affected by the external addition of p-anisidine or Ran(II). Four isoenzymes were detected in these cultures, with pIs between 3.76 and 3.60. In a wheat bran medium, four isoenzymes with pIs in the range 3.63-3.46, plus a fifth isoenzyme of high pI (4.82), were also identified. The absorption spectrum of a pool containing the four isoenzymes from rich medium shows a maximum at 600 nn, typical of laccase possessing a type I copper atom. The molecular mass of the isoenzyme with pI 3.60 is 79 kDa, as determined by SDS/PAGE. Upon treatment with endoglycosidase F, the molecular mass of this isoform decreases to 63 kDa...

Biochemical characterization of sugarcane (Saccharum spp.) cultivars: isoenzymes, solubre protein and brix value; Caracterização bioquímica de cultivares de cana-de-açúcar (Saccharum spp.): isoenzimas, proteína solúvel e valor brix

Almeida, M. de; Crócomo, O. J.
Fonte: Universidade de São Paulo. Escola Superior de Agricultura Luiz de Queiroz Publicador: Universidade de São Paulo. Escola Superior de Agricultura Luiz de Queiroz
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; ; ; ; Formato: application/pdf
Publicado em 01/12/1994 POR
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In the present work the isoenzyme profiles of the enzymes esterase and peroxidase, the level of total soluble protein and the soluble solids (sucrose) were determined of the following sugarcane (Saccharum spp.) cultivare: NA 56-79; IAC 52-150; IAC 64-257; SP 70-1143; SP 71-3146; SP 71-3149; SP 71-1406; SP 71-6163; SP 71-61-68 and SP 71-799. Esterase isoenzymes showed a specific electrophoretic pattern for each one of the cultivare, while the peroxidase allowed to arrange the cultivare in groups, each one with a specific electrophoretic pattern. The isoenzymes of both esterase and peroxidase were constant in a given cultivar. Total soluble protein levels and soluble solids (sucrose, Brix value) varied among the cultivare. Statistical analysis showed that these biochemical parameters are useful for the characterization of the cultivare under study.; No presente trabalho foram determinados o perfil isoenzimático diferencial de esterase e peroxidase, a proteína total solúvel e os sólidos solúveis (sacarose) em graus brix, de 10 cultivares de cana-de-açúcar (Saccharum spp.) atualmente cultivados no Brasil. Os cultivares estudados foram: NA 56-79, IAC 52-150, IAC 64-257, SP 70-1143, SP 71-3146, SP 71-3149, SP 71-1406, SP 71-6163, SP 71-61-68 e SP 71-799. Com os dados obtidos foi possível comprovar o valor taxonômico das características bioquímicas que representam uma inovação em taxonomia de cana-de-açúcar no Brasil. As isoenzimas de esterase apresentaram um padrão eletroforético específico para cada cultivar estudado...