Consulta: subjectFacets:"Thermostability"
Registros recuperados: 11
Data/hora: 02/06/2024 06:56:30

Behavior of Araujiain, a new cysteine phytoprotease, in organic media with low water content
Provedor de dados: 69
Autores: Quiroga,Evelina; Priolo,Nora; Marchese,José; Barberis,Sonia.
In this paper we studied the effect of different organic solvents (1-octanol, trichloroethylene, ethanol, ethyl acetate, tetrahydrofuran, cyclohexane, propanone, acetonitrile, dichloromethane, chlorobenzene, N,N-dimethylformamide, acetophenone, diethyl ether, methanol, ethylene glycol and toluene) with low and constant water content on substrate preferences, thermostability and stability (caseinolytic activity retention after 4 h) of proteases of Araujia hortorum Fourn. (Asclepiadaceae). The stability of araujiain was high in N,N-dimethylformamide and ethanol at 40&amp;ordm;C, but decreased at higher temperature. Araujiain substrates preferences in buffer Tris-HCl (pH 8), ethylene glycol and N,N-dimethylformamide exhibited different patterns, but the...
Tipo: Journal article
Palavras-chave: Araujia hortorum Fourn; Organic solvents; Plant protease; Substrate preferences; Thermostability.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000100004

Immobilization and stability studies of a lipase from thermophilic Bacillus sp: The effect of process parameters on immobilization of enzyme
Provedor de dados: 69
Autores: Nawani,Neerupma; Singh,Rajvinder; Kaur,Jagdeep.
A thermostable lipase was partially purified from the culture supernatant of a thermophilic Bacillus sp. The enzyme is optimally active at 60&amp;ordm;C and pH 8.0. The enzyme showed enhancement in activity in presence of benzene or hexane (30% v/v each). The activity (assayed by determining the release of pNP from pNP laurate) was stimulated up to 60% of these solvents in enzyme reaction mixture. The catalytic properties of this thermostable enzyme can be further improved via the use of different immobilization techniques and reaction conditions. Enzyme was immobilized on different solid supports and their enzyme activity and stability was compared. The enzyme was adsorbed on silica and HP-20 beads followed by cross-linking with gluteraldehyde on HP-20,...
Tipo: Journal article
Palavras-chave: Esterification; Immobilization; Lipase; Thermostability.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000500011

Peroxidase production from hairy root cultures of red beet (Beta vulgaris)
Provedor de dados: 69
Autores: Rudrappa,Thimmaraju; Neelwarne,Bhagyalakshmi; Kumar,Vinod; Lakshmanan,Venkatachalam; Venkataramareddy,Sreedhar Reddampalli; Aswathanarayana,Ravishankar Gokare.
The genetically transformed roots of red beet have been shown, for the first time, to produce very high levels of peroxidase (POD; EC 1.11.1.7) accounting for 1.21 x 10(6) Units L-1. Of the ten clones established using different strains of Agrobacterium rhizogenes, one was that from the strain LMG-150, three each from A 2/83, A 20/83 and A4. All the clones showed true integration of T-DNA when tested by PCR and Southern hybridization methods. Each clone differed significantly from the others in growth, hormone dependency and POD production where LMG-150 produced highest biomass (140 g FW L-1) as well as POD (ranging from 8000-9000 U g-1 FW and 1.18 x 10(6) U L-1 with a specific activity of 600 U mg-1 protein) on hormone-free medium, both in shake-flask as...
Tipo: Journal article
Palavras-chave: Agrobacterium rhizogenes; Auxins; Elicitation; T-DNA; Thermostability; Transformation.
Ano: 2005
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582005000200008

Les ADN polymérases B et D de l'Archaea hyperthermophile, Pyrococcus abyssi : contribution à l'étude des relations structure-fonction
Provedor de dados: 5
Autores: Castrec, Benoit.
DNA replication is a functionally conserved mechanism among the three domains of life. This processus is performed by DNA polymerases with two accessories factors, PCNA and RF-C, sliding clamp and clamp loader, respectively. Our model of study, the Euryarchaeota Pyrococcus abyssi, possesses one monomeric DNA polymerase, belonging to the Family B, and one heterodimeric DNA polymerase, belonging to the Family D. Usually, proteins interact with PCNA at a hydrophobic pocket which is formed by the IDCL (interdomain connecting loop) and the C-terminus. These interactions are mediated through common motifs like the PIP box (motif PCNA interacting Protein). We have demonstrated that Pol B has just one PIP box motif at the C-terminus, while Pol D has two PIP-type...
Tipo: Text
Palavras-chave: Thermostability; Interactions; Motifs; DNA replication; RF C; PCNA; DNA polymerases; Archaea; Thermostabilité; Interactions; Motifs; Réplication de l'ADN; RF C; PCNA; ADN polymérases; Archaea.
Ano: 2009
URL: http://archimer.ifremer.fr/doc/2009/these-6940.pdf

Partial purification and characterization of ribonucleases from roots, stem and leaves of cowpea
Provedor de dados: 93
Autores: FRANCO,OCTÁVIO LUIZ; GONDIM,LORRANCE ABREU; BEZERRA,KÁTIA REGINA; GUERRA,MARIA ELANE DE CARVALHO; LIMA,CARMEM ROGÉLIA FARIAS MACHADO; ENÉAS-FILHO,JOAQUIM; PRISCO,JOSÉ TARQUÍNIO; GOMES-FILHO,ENÉAS.
Partial purification and characterization of ribonucleases (RNase; EC 3.1.27.1) present in roots, stem and leaves of 5 day-old Pitiúba cowpea [Vigna unguiculata (L.) Walp.] seedlings are described. Crude extracts from the different tissues were precipitated with ammonium sulfate followed by ionic exchange chromatography (CM-Cellulose) resulting in purification factors of 48-fold for roots, 21 for stem and 42 for leaves. No deoxyribonuclease activity was practically observed. The molecular masses of the RNases did not significantly differ, averaging 16.3 kDa. Leaf RNase was stable up to 50ºC while the others were inactivated at this temperature. The maximal inactivation for both stem and roots RNases was reached at 70ºC while for leaf it occurred at 80ºC....
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Enzyme effectors; Molecular mass; Nuclease; Optimum pH; Seedlings; Thermostability; Vigna unguiculata.
Ano: 2001
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-31312001000300010

Extremely thermophilic microorganisms and their polymer-hidrolytic enzymes
Provedor de dados: 59
Autores: Andrade,Carolina M.M.C.; Pereira Jr.,Nei; Antranikian,Garo.
Thermophilic and hyperthermophilic microorganisms are found as normal inhabitants of continental and submarine volcanic areas, geothermally heated sea-sediments and hydrothermal vents and thus are considered extremophiles. Several present or potential applications of extremophilic enzymes are reviewed, especially polymer-hydrolysing enzymes, such as amylolytic and hemicellulolytic enzymes. The purpose of this review is to present the range of morphological and metabolic features among those microorganisms growing from 70oC to 100°C and to indicate potential opportunities for useful applications derived from these features.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Archaea; Extremophiles; Amylases; Xylanases; Pullulanases; Thermostability.
Ano: 1999
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37141999000400001

Laccase produced by a thermotolerant strain of Trametes trogii LK13
Provedor de dados: 58
Autores: Yan,Jinping; Chen,Yuhui; Niu,Jiezhen; Chen,Daidi; Chagan,Irbis.
Thermophilic and thermotolerant micro-organisms strains have served as the natural source of industrially relevant and thermostable enzymes. Although some strains of the Trametes genus are thermotolerant, few Trametes strains were studied at the temperature above 30 °C until now. In this paper, the laccase activity and the mycelial growth rate for Trametes trogii LK13 are superior at 37 °C. Thermostability and organic cosolvent tolerance assays of the laccase produced at 37 °C indicated that the enzyme possessed fair thermostability with 50% of its initial activity at 80 °C for 5 min, and could remain 50% enzyme activity treated with organic cosolvent at the concentration range of 25%–50% (v/v). Furthermore, the test on production of laccase and...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Trametes trogii; Thermotolerant fungi; Laccase; Thermostability; Organic cosolvent tolerance.
Ano: 2015
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822015000100059

Comparative study of two purified inulinases from thermophile Thielavia Terrestris NRRL 8126 and mesophile Aspergillus Foetidus NRRL 337 grown on Cichorium Intybus l
Provedor de dados: 58
Autores: Fawzi,Eman Mohamed.
Thirty fungal species grown on Cichorium intybus L. root extract as a sole carbon source, were screened for the production of exo-inulinase activities. The thermophile Thielavia terrestris NRRL 8126 and mesophile Aspergillus foetidus NRRL 337 gave the highest production levels of inulinases I &amp;amp; II at 50 and 24 ºC respectively. Yeast extract and peptone were the best nitrogen sources for highest production of inulinases I &amp;amp; II at five and seven days of incubation respectively. The two inulinases I &amp;amp; II were purified to homogeneity by gel-filtration and ion-exchange chromatography with 66.0 and 42.0 fold of purification respectively. The optimum temperatures of purified inulinases I &amp;amp; II were 75 and 50 ºC respectively....
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Inulinases; Production; Purification; Thermophile; Thermostability.
Ano: 2011
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822011000200028

Thermostability of xylanolytic enzymes produced by Lentinula edodes UFV70
Provedor de dados: 58
Autores: Ribeiro,Liliane Fraga Costa; Vaz,Marcelo Gomes Marçal Vieira; Chaves-Alves,Virgínia Maria; Vanetti,Maria Cristina Dantas; Kasuya,Maria Catarina Megumi; Passos,Flávia Maria Lopes; Nascimento,Antônio Galvão do.
Xylanolytic enzymes produced by Lentinula edodes UFV70, cultivated in eucalyptus sawdust/rice bran medium, were stable at 50, 60 and 65ºC for 21 hours, losing only 15-25% activity. Fungus incubation at 50ºC for 12 hours and at 65ºC for 24 hours increased the amount of xylose produced.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Xylanase; Thermostability; Lentinula edodes; Xylose.
Ano: 2012
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822012000100021

Thermal stability of xylanases produced by Aspergillus awamori
Provedor de dados: 58
Autores: Lemos,Judith Liliana Solórzano; Bon,Elba P.S.; Santana,Maria de Fátima Ebole; Pereira Junior,Nei.
The effect of temperature on the activity and stability of endoxylanase and beta-xylosidase from Aspergillus awamori was investigated. The growth of A. awamori in milled sugar cane bagasse produced predominantly extracellular endoxylanase (30 U/ml) and lower amounts of beta-xylosidase (1.3 U/ml). Grown in sugar cane bagasse as the principal carbon source, the microorganism produced a quite stable beta-xylosidase in a temperature range of 35-55°C, but it exhibited a lower thermostable endoxylanase. The thermostability of endoxylanase was enhanced through addition of polyhydric alcohols, mainly 2 M xylitol and sorbitol solutions. Particular stability upon storage (100%) was found for endoxylanase at -4°C for 165 days. Yet for beta-xylosidase, an activity...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Aspergillus awamori; Thermostability; Xylanases.
Ano: 2000
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822000000300010

Purification and characterization of trypsin inhibitor from Cicer arietinum L. and its efficacy against Helicoverpa armigera
Provedor de dados: 61
Autores: Kansal,Rekha; Kumar,Mukesh; Kuhar,Kalika; Gupta,Ram N.; Subrahmanyam,Bhattiprolu; Koundal,Kirpa R.; Gupta,Vijay K.
Protease inhibitors in legumes are one of the most promising weapons that confer resistance against insects by inhibiting proteases present in the gut of insect larvae. In the present study, trypsin inhibitor activity was detected in the seed flour extracts of 10 selected varieties of chickpea. The presence of inhibitor was confirmed by dot blot analysis. All the varieties showed inhibitory activity in vitro against the gut protease of Helicoverpa armigera (HGP). Trypsin inhibitor has been purified to near homogeneity to 60.46 fold and 29.20% recovery from chickpea seeds using heat denaturation, ammonium sulphate fractionation, DEAE-Sephadex A-25 and Sephadex G-75. The purified inhibitor showed a single band on SDS-PAGE corresponding to molecular mass of...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Chickpea; Dot blot; Insect bioassay; PH stability; Thermostability.
Ano: 2008
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202008000400007