scholarly journals Purification and some characteristics of the acetylxylan esterase from Schizophyllum commune

1994 ◽  
Vol 298 (3) ◽  
pp. 751-755 ◽  
Author(s):  
N Halgasová ◽  
E Kutejová ◽  
J Timko
Keyword(s):  
Enzyme Activity ◽  
Ion Exchange ◽  
Molecular Mass ◽  
Schizophyllum Commune ◽  
Gel Filtration ◽  
Temperature Optimum ◽  
Ph Optimum ◽  
Full Activity ◽  
Sds Page ◽  
Acetylxylan Esterase

Acetylxylan esterase from Schizophyllum commune was purified using ion-exchange and hydrophobic chromatography. The enzyme has a molecular mass of 31 kDa, as determined by SDS/PAGE, or 18 kDa, according to gel filtration. Glycosylation of the enzyme was not detected. Acetylxylan esterase is relatively stable under laboratory conditions; it retains full activity at pH 6.2-8.5 upon incubation at 25 degrees C for 7 h, but loses nearly the whole activity upon incubation at 60 degrees C for 30 min. The pH optimum of the enzyme activity is 7.7 and its temperature optimum lies between 30 and 45 degrees C. Ca2+ and Co2+ inhibit markedly the activity of acetylxylan esterase at a concentration of 10 mM, as do Mn2+, Zn2+, Fe2+ and Cu2+ at a concentration of 1 mM.

Production of Geotrichum candidum polygalacturonases via solid state fermentation on grape pomace

2012 ◽  
Vol 66 (9) ◽  
Author(s):  
Kateřina Illková ◽  
Zuzana Zemková ◽  
Dana Flodrová ◽  
Jakub Jäger ◽  
Dagmar Benkovská ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Molecular Mass ◽  
Extracellular Enzymes ◽  
Gel Filtration ◽  
Pectin Methylesterase ◽  
Geotrichum Candidum ◽  
Grape Pomace ◽  
Temperature Optimum ◽  
Ph Optimum ◽  
Sds Page

AbstractGeotrichum candidum CCY 16-1-29 (teleomorph Galactomyces geotrichum) is able to grow and produce polygalacturonase of remarkable activities on pectin or grape pomace as a sole carbon source. The highest activities of extracellular enzymes were found on the third and the seventh day of cultivation. After extraction and precipitation, polygalacturonases produced in these cultivation periods were characterized. Production of multiple forms of polygalacturonase was observed in both cultivation periods. Two major forms, polygalacturonase with random action pattern (endo-PGase, EC 3.2.1.15) and oligogalacturonate hydrolase (exoPGase, exopolygalacturonase preferring oligogalacturonides as substrates), as well as numerous minor forms were detected by IEF-PAGE using the print technique detection. EndoPGase was identified by mass spectrometry. The major forms have similar isoelectric points (below pH 6.0) and pH optima (4.6 and 4.8, respectively). pH optimum of 4.6 was associated with exoPGase and that of 4.8 with endoPGase. Both enzymes were stable after freeze-drying and storage at 4°C. EndoPGase had molecular mass of about 29 kDa (36 kDa by SDS-PAGE) as determined by gel filtration, temperature optimum of about 45°C and it was stable only below 35°C. Molecular mass of exoPGase was about 50 kDa, its temperature optimum was about 60°C, and it was stable to 60°C. Optimal substrate for exoPGase was a pentamer, for endoPGase it was a pectate. Values of K m for optimal substrate reached the values of 11.4 × 10−5 M for for exoPGase and 6.6 × 10−5 M for endoPGase. Pectin methylesterase as another pectolytic enzyme was also identified by mass spectrometry.

scholarly journals Isolation and partial characterization of protease from Pseudomonas aeruginosa ATCC 27853

2010 ◽  
Vol 75 (8) ◽  
pp. 1041-1052 ◽  
Author(s):  
Lidija Izrael-Zivkovic ◽  
Gordana Gojgic-Cvijovic ◽  
Ivanka Karadzic
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Molecular Mass ◽  
Gel Filtration ◽  
Zinc Ion ◽  
Metal Chelators ◽  
Temperature Optimum ◽  
Ph Optimum ◽  
Sds Page ◽  
Potential Use

Enzymatic characteristics of a protease from medically important, referent strain of Pseudomonas aeruginosa ATCC 27853 were determined. According to SDS PAGE and gel filtration it was estimated that molecular mass of the purified enzyme was about 15 kDa. Other enzymatic properties were found to be: pH optimum 7.1, pH stability between pH 6.5 and pH 10; temperature optimum around 60?C while the enzyme was stable at 60?C for 30 min. The inhibition of the enzyme was observed with the metal chelators such as EDTA and 1,10- phenanthroline, suggesting that the protease is a metalloenzyme. Further more it was determined that enzyme contains one mole of zinc ion per mole of enzyme. The protease is stable in the presence of different organic solvents, which enable potential use for synthesis of peptides.

Production, purification, and characterization of an extracellular endo-β-1, 3-glucanase from a monokaryon of Schizophyllum commune ATCC 38548 defective in exo-β-1, 3-glucanase formation

1994 ◽  
Vol 40 (1) ◽  
pp. 18-23 ◽  
Author(s):  
Andreas Prokop ◽  
Peter Rapp ◽  
Fritz Wagner
Keyword(s):  
Molecular Mass ◽  
Schizophyllum Commune ◽  
Gel Filtration ◽  
Anion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Glucanase Activity ◽  
Sds Page ◽  
S 100 ◽  
Reduced Activity

Production of extracellular β-1, 3-glucanase activity by a monokaryotic Schizophyllum commune strain was monitored and results indicated that the β-glucanase activity consisted of an endo- β-1, 3-glucanase activity, besides a negligible amount of β-1, 6-glucanase and β-glucosidase activity. Unlike the β-1, 3-glucanase production of the dikaryotic parent strain S. commune ATCC 38548, the β-1, 3-glucanase formation of the monokaryon was not regulated by catabolite repression. The endo- β-1, 3-glucanase of the monokaryon was purified from the culture filtrate by lyophilization, anion exchange chromatography on Mono Q, and gel filtration on Sephacryl S-100. It appeared homogeneous on SDS-PAGE with a molecular mass of 35.5 kDa and the isoelectric point was 3.95. The enzyme was only active toward glucans containing β-1, 3-linkages, including lichenan, a β-1, 3-1, 4-D-glucan. It attacked laminarin in an endo-like fashion to form laminaribiose, laminaritriose, and high oligosaccharides. While the extracellular β-glucanases from the dikaryotic S. commune ATCC 38548 degraded significant amounts of schizophyllan, the endo- β-1, 3-glucanase from the monokaryon showed greatly reduced activity toward this high molecular mass β-1, 3-/β-1, 6-glucan. The Km of the endoglucanase, using laminarin as substrate, was 0.28 mg/mL. Optimal pH and temperature were 5.5 and 50 °C, respectively. The enzyme was stable between pH 5.5 and 7.0 and at temperatures below 50 °C. The enzyme was completely inhibited by 1 mM Hg2+. Growth of the monokaryotic S. commune strain was not affected by its constitutive endo- β-1, 3-glucanase formation.Key words: endo- β-1, 3-glucanase, Schizophyllum commune, monokaryon, constitutive endo- β-1, 3-glucanase formation.

scholarly journals Purification and characterization of an extracellular (1 → 6)-β-glucanase from the filamentous fungus Acremonium persicinum

1996 ◽  
Vol 316 (3) ◽  
pp. 841-846 ◽  
Author(s):  
Stuart M. PITSON ◽  
Robert J. SEVIOUR ◽  
Barbara M. McDOUGALL ◽  
Bruce A. STONE ◽  
Maruse SADEK
Keyword(s):  
Molecular Mass ◽  
Filamentous Fungus ◽  
Gel Filtration ◽  
Purification And Characterization ◽  
Eisenia Bicyclis ◽  
Ph Optimum ◽  
Hydrolysis Products ◽  
Sds Page ◽  
Hydrolysis Of

An endo-(1 → 6)-β-glucanase has been isolated from the culture filtrates of the filamentous fungus Acremonium persicinum and purified by (NH4)2SO4 precipitation followed by anion-exchange and gel-filtration chromatography. SDS/PAGE of the purified enzyme gave a single band with an apparent molecular mass of 42.7 kDa. The enzyme is a non-glycosylated, monomeric protein with a pI of 4.9 and pH optimum of 5.0. It hydrolysed (1 → 6)-β-glucans (pustulan and lutean), initially yielding a series of (1 → 6)-β-linked oligoglucosides, consistent with endo-hydrolytic action. Final hydrolysis products from these substrates were gentiobiose and gentiotriose, with all products released as β-anomers, indicating that the enzyme acts with retention of configuration. The purified enzyme also hydrolysed Eisenia bicyclis laminarin, liberating glucose, gentiobiose, and a range of larger oligoglucosides, through the apparent hydrolysis of (1 → 6)-β- and some (1 → 3)-β-linkages in this substrate. Km values for pustulan, lutean and laminarin were 1.28, 1.38, and 1.67 mg/ml respectively. The enzyme was inhibited by N-acetylimidazole, N-bromosuccinimide, dicyclohexylcarbodi-imide, Woodward's Regent K, 2-hydroxy-5-nitrobenzyl bromide, KMnO4 and some metal ions, whereas D-glucono-1,5-lactone and EDTA had no effect.

scholarly journals Characterization of the hydroxymethylglutaryl-CoA lyase precursor, a protein targeted to peroxisomes and mitochondria

1996 ◽  
Vol 315 (1) ◽  
pp. 71-75 ◽  
Author(s):  
Lyudmila I. ASHMARINA ◽  
Marie-France ROBERT ◽  
Marc-André ELSLIGER ◽  
Grant A. MITCHELL
Keyword(s):  
Molecular Mass ◽  
Gel Filtration ◽  
Leader Peptide ◽  
Mitochondrial Targeting ◽  
Ph Optimum ◽  
Sds Page ◽  
Peroxisomal Targeting ◽  
Quaternary Structures ◽  
Hydroxymethylglutaryl Coa Lyase

We previously showed that human liver hydroxymethylglutaryl-CoA (HMG-CoA) lyase (HL; EC 4.1.3.4) is found in both mitochondria and peroxisomes. HL contains a 27-residue N-terminal mitochondrial targeting sequence which is cleaved on mitochondrial entry, as well as a C-terminal Cys-Lys-Leu peroxisomal targeting motif. Because peroxisomal HL has a greater molecular mass and more basic pI value than mitochondrial HL, we predicted that peroxisomal HL retains the mitochondrial leader. To test this hypothesis, we expressed both the precursor (pHL) and mature (mHL) peptides in Escherichia coli and studied their properties. pHL purified by ion-exchange and hydrophobic chromatography had a pI of 7.6 on FPLC chromatofocusing and a molecular mass of 34.5 kDa on SDS/PAGE, similar to our findings for peroxisomal HL. For purified mHL, pI (6.2) and molecular mass (32 kDa) values resemble those of mitochondrial HL. Purified pHL is similar to mHL in Km for HMG-CoA (44.8 μM), kcat (6.3 min-1) and pH optimum (9.0–9.5). However, the quaternary structures of pHL and mHL differ. On Superose 12 FPLC gel filtration and also on ultrafiltration, both in the presence and in the absence of HMG-CoA, pHL behaves as a monomer whereas mHL migrates as a dimer. We conclude that the HL precursor is probably identical to peroxisomal HL, that its catalytic properties resemble those of mature mitochondrial HL, and that the mitochondrial leader peptide prevents dimerization of pHL.

Cysteine proteinase of Phascolomyces articulosus: purification and properties

1986 ◽  
Vol 64 (11) ◽  
pp. 2441-2445 ◽  
Author(s):  
R. Balasubramanian ◽  
M. S. Manocha
Keyword(s):  
Enzyme Activity ◽  
Cysteine Proteinase ◽  
Gel Filtration ◽  
Apparent Molecular Weight ◽  
Iodoacetic Acid ◽  
Phenylmethylsulfonyl Fluoride ◽  
Temperature Optimum ◽  
Ph Optimum ◽  
Salting Out ◽  
Purification And Properties

A proteinase from the mycelial extracts of Phascolomyces articulosus has been purified by salting out with ammonium sulphate, gel filtration, hydroxyapatite adsorption, and affinity chromatography. The proteinase rapidly hydrolysed haemoglobin but failed to hydrolyse any of the synthetic peptides tested. The enzyme is a glycoprotein with an apparent molecular weight of 12 800. The carbohydrate content was estimated to be 65%. It has a temperature optimum of 20 °C, pH optimum of 3.0, and has a Km value of 6.6 mg∙mL−1 for denatured haemoglobin. Iodoacetic acid, iodoacetamide, benzamidine, as well as all the heavy metals tested inhibited the enzyme activity. The enzyme activity was not enhanced by reducing agents such as cysteine, ethylenediaminetetra acetic acid, and dithiothreitol, the latter, however, reversed inhibition by phenylmethylsulfonyl fluoride. The inhibitor studies suggest that the enzyme belongs to the group of cysteine proteinases.

A novel tannase from Aspergillus niger with β-glucosidase activity

Microbiology ◽  
2003 ◽  
Vol 149 (10) ◽  
pp. 2941-2946 ◽  
Author(s):  
M. Ascención Ramírez-Coronel ◽  
Gustavo Viniegra-González ◽  
Alan Darvill ◽  
Christopher Augur
Keyword(s):  
Aspergillus Niger ◽  
Hplc Analysis ◽  
Gel Filtration ◽  
Culture Broth ◽  
Temperature Optimum ◽  
Ph Optimum ◽  
Glucosidase Activity ◽  
Sds Page ◽  
Hydrolysable Tannins ◽  
Molecular Masses

An extracellular tannase was produced from solid-state cultures of Aspergillus niger. The enzyme was purified to homogeneity from the cell-free culture broth by preparative isoelectric focusing and by FPLC using anion-exchange and gel-filtration chromatography. SDS-PAGE analysis as well as gel localization studies of purified tannase indicated the presence of two enzyme forms, with molecular masses of 90 kDa and 180 kDa. The tannase had an isoelectric point of 3·8, a temperature optimum of 60–70 °C and a pH optimum of 6·0. The substrate specificity of the tannase was determined by HPLC analysis of tannin substrates and products. The enzyme was able to remove gallic acid from both condensed and hydrolysable tannins. Internal sequences were obtained from each of the gel-purified and trypsin-digested tannase forms. The peptide sequences obtained from both forms were identical to sequences within a β-glucosidase from Aspergillus kawachii. The purified tannase was tested for β-glucosidase activity and was shown to hydrolyse cellobiose efficiently. However, no β-glucosidase activity was detected when the enzyme was assayed in the presence of tannic acid.

scholarly journals Identification and characterization of Sulfolobus solfataricusD-gluconate dehydratase: a key enzyme in the non-phosphorylated Entner–Doudoroff pathway

2005 ◽  
Vol 387 (1) ◽  
pp. 271-280 ◽  
Author(s):  
Seonghun KIM ◽  
Sun Bok LEE
Keyword(s):  
Molecular Mass ◽  
Gel Filtration ◽  
Maximal Activity ◽  
Genome Database ◽  
Sds Page ◽  
Key Enzyme ◽  
Bivalent Metal Ions ◽  
Ammonium Sulphate Fractionation ◽  
Identification And Characterization

The extremely thermoacidophilic archaeon Sulfolobus solfataricus utilizes D-glucose as a sole carbon and energy source through the non-phosphorylated Entner–Doudoroff pathway. It has been suggested that this micro-organism metabolizes D-gluconate, the oxidized form of D-glucose, to pyruvate and D-glyceraldehyde by using two unique enzymes, D-gluconate dehydratase and 2-keto-3-deoxy-D-gluconate aldolase. In the present study, we report the purification and characterization of D-gluconate dehydratase from S. solfataricus, which catalyses the conversion of D-gluconate into 2-keto-3-deoxy-D-gluconate. D-Gluconate dehydratase was purified 400-fold from extracts of S. solfataricus by ammonium sulphate fractionation and chromatography on DEAE-Sepharose, Q-Sepharose, phenyl-Sepharose and Mono Q. The native protein showed a molecular mass of 350 kDa by gel filtration, whereas SDS/PAGE analysis provided a molecular mass of 44 kDa, indicating that D-gluconate dehydratase is an octameric protein. The enzyme showed maximal activity at temperatures between 80 and 90 °C and pH values between 6.5 and 7.5, and a half-life of 40 min at 100 °C. Bivalent metal ions such as Co2+, Mg2+, Mn2+ and Ni2+ activated, whereas EDTA inhibited the enzyme. A metal analysis of the purified protein revealed the presence of one Co2+ ion per enzyme monomer. Of the 22 aldonic acids tested, only D-gluconate served as a substrate, with Km=0.45 mM and Vmax=0.15 unit/mg of enzyme. From N-terminal sequences of the purified enzyme, it was found that the gene product of SSO3198 in the S. solfataricus genome database corresponded to D-gluconate dehydratase (gnaD). We also found that the D-gluconate dehydratase of S. solfataricus is a phosphoprotein and that its catalytic activity is regulated by a phosphorylation–dephosphorylation mechanism. This is the first report on biochemical and genetic characterization of D-gluconate dehydratase involved in the non-phosphorylated Entner–Doudoroff pathway.

A metalloproteinase extracellularly released byCrithidia deanei

2003 ◽  
Vol 49 (10) ◽  
pp. 625-632 ◽  
Author(s):  
Claudia Masini d'Avila-Levy ◽  
Rodrigo F Souza ◽  
Rosana C Gomes ◽  
Alane B Vermelho ◽  
Marta H Branquinha
Keyword(s):  
Molecular Mass ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Gel Filtration ◽  
Residual Activity ◽  
Major Protein ◽  
Motile Cells ◽  
Sds Page ◽  
Triton X

Actively motile cells from a cured strain of Crithidia deanei released proteins in phosphate buffer (pH 7.4). The molecular mass of the released polypeptides, which included some proteinases, ranged from 19 to 116 kDa. One of the major protein bands was purified to homogeneity by a combination of anion-exchange and gel filtration chromatographs. The apparent molecular mass of this protein was estimated to be 62 kDa by sodium dodecyl sulfate – polyacrylamide gel electrophoresis (SDS–PAGE). The incorporation of gelatin into SDS–PAGE showed that the purified protein presented proteolytic activity in a position corresponding to a molecular mass of 60 kDa. The enzyme was optimally active at 37 °C and pH 6.0 and showed 25% of residual activity at 28 °C for 30 min. The proteinase was inhibited by 1,10-phenanthroline and EDTA, showing that it belonged to the metalloproteinase class. A polyclonal antibody to the leishmanial gp63 reacted strongly with the released C. deanei protease. After Triton X-114 extraction, an enzyme similar to the purified metalloproteinase was detected in aqueous and detergent-rich phases. The detection of an extracellular metalloproteinase produced by C. deanei and some other Crithidia species suggests a potential role of this released enzyme in substrate degradation that may be relevant to the survival of trypanosomatids in the host.Key words: endosymbiont, trypanosomatid, extracellular, proteinase.

scholarly journals Characterization of Biosynthetic Enzymes for Ectoine as a Compatible Solute in a Moderately Halophilic Eubacterium, Halomonas elongata

1999 ◽  
Vol 181 (1) ◽  
pp. 91-99 ◽  
Author(s):  
Hisayo Ono ◽  
Kazuhisa Sawada ◽  
Nonpanga Khunajakr ◽  
Tao Tao ◽  
Mihoko Yamamoto ◽  
...  
Keyword(s):  
Molecular Mass ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Gel Filtration ◽  
Apparent Molecular Mass ◽  
Optimum Temperature ◽  
Sds Page ◽  
Halomonas Elongata ◽  
Optimum Ph

ABSTRACT 1,4,5,6-Tetrahydro-2-methyl-4-pyrimidinecarboxylic acid (ectoine) is an excellent osmoprotectant. The biosynthetic pathway of ectoine from aspartic β-semialdehyde (ASA), in Halomonas elongata, was elucidated by purification and characterization of each enzyme involved. 2,4-Diaminobutyrate (DABA) aminotransferase catalyzed reversively the first step of the pathway, conversion of ASA to DABA by transamination with l-glutamate. This enzyme required pyridoxal 5′-phosphate and potassium ions for its activity and stability. The gel filtration estimated an apparent molecular mass of 260 kDa, whereas molecular mass measured by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) was 44 kDa. This enzyme exhibited an optimum pH of 8.6 and an optimum temperature of 25°C and had Km s of 9.1 mM forl-glutamate and 4.5 mM for dl-ASA. DABA acetyltransferase catalyzed acetylation of DABA to γ-N-acetyl-α,γ-diaminobutyric acid (ADABA) with acetyl coenzyme A and exhibited an optimum pH of 8.2 and an optimum temperature of 20°C in the presence of 0.4 M NaCl. The molecular mass was 45 kDa by gel filtration. Ectoine synthase catalyzed circularization of ADABA to ectoine and exhibited an optimum pH of 8.5 to 9.0 and an optimum temperature of 15°C in the presence of 0.5 M NaCl. This enzyme had an apparent molecular mass of 19 kDa by SDS-PAGE and a Km of 8.4 mM in the presence of 0.77 M NaCl. DABA acetyltransferase and ectoine synthase were stabilized in the presence of NaCl (>2 M) and DABA (100 mM) at temperatures below 30°C.

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