A novel ribonuclease from the veiled lady mushroom Dictyophora indusiata

2003 ◽  
Vol 81 (6) ◽  
pp. 373-377 ◽  
Author(s):  
Hexing Wang ◽  
Tzi Bun Ng
Keyword(s):  
Molecular Mass ◽  
Deae Cellulose ◽  
Transfer Rna ◽  
Rnase Activity ◽  
Fruiting Bodies ◽  
Terminal Sequence ◽  
Temperature Optimum ◽  
Ph Optimum

A ribonuclease (RNase), exhibiting a molecular mass of 28 kDa and specificity toward polyU and polyA and possessing an N-terminal sequence dissimilar to previously reported mushroom RNases, was isolated from dried fruiting bodies of veiled lady mushroom (Dictyophora indusiata). It demonstrated an RNase activity of 564 U/mg toward yeast transfer RNA. The RNase was adsorbed on DEAE-cellulose, CM-Sepharose, and Q-Sepharose. It demonstrated a pH optimum of 4–4.5 and a temperature optimum of 60 °C. There was a loss of RNase activity at temperatures above 60 °C.Key words: ribonuclease, Dictyophora indusiata, mushroom, purification.

A novel ribonuclease from fresh fruiting bodies of the portabella mushroom Agaricus bisporus

2006 ◽  
Vol 84 (2) ◽  
pp. 178-183 ◽  
Author(s):  
H X Wang ◽  
T B Ng
Keyword(s):  
Carboxymethyl Cellulose ◽  
Agaricus Bisporus ◽  
Deae Cellulose ◽  
Fruiting Bodies ◽  
Terminal Sequence ◽  
Temperature Optimum ◽  
Ph Optimum

A 14 kDa ribonuclease with a novel N-terminal sequence was isolated from fresh fruiting bodies of the portabella mushroom. It was adsorbed on DEAE-cellulose and carboxymethyl-cellulose, and demonstrated the highest ribonucleolytic potency toward poly (A), 60% as much activity toward poly (C), 40% as much activity toward poly (U), and the least activity (7% as much) toward poly (G). It exhibited a pH optimum at pH 4.5 and a temperature optimum at 60 °C. Its activity at 100 °C was higher than that at 20 °C.Key words: ribonuclease, portabella mushroom, isolation.

Flammulin: A novel ribosome-inactivating protein from fruiting bodies of the winter mushroom Flammulina velutipes

2000 ◽  
Vol 78 (6) ◽  
pp. 699-702 ◽  
Author(s):  
H X Wang ◽  
T B Ng
Keyword(s):  
Deae Cellulose ◽  
Flammulina Velutipes ◽  
Fruiting Bodies ◽  
Terminal Sequence ◽  
Ribosome Inactivating Protein ◽  
Ribosome Inactivating Proteins ◽  
Rabbit Reticulocyte Lysate System ◽  
Free Translation ◽  
Reticulocyte Lysate ◽  
Low Ionic Strength

A protein with a molecular weight of 40 kDa, capable of inhibiting cell-free translation in a rabbit reticulocyte lysate system with an IC50 of 0.25 nM, was isolated from fruiting bodies of the mushroom Flammulina velutipes. The protein, designated flammulin, was devoid of ribonuclease activity. Flammulin was unadsorbed on DEAE-cellulose at neutral pH and low ionic strength and adsorbed on CM-Sepharose and Affi-gel blue gel under similar conditions. Its N-terminal sequence demonstrates sites of similarity to those of plant ribosome-inactivating proteins (RIPs).Key words: mushroom, ribosome-inactivating protein, fruiting body.

Purification of a third distinct xylanase from the xylanolytic system of Trichoderma harzianum

1986 ◽  
Vol 32 (7) ◽  
pp. 570-576 ◽  
Author(s):  
Ken K. Y. Wong ◽  
Larry U. L. Tan ◽  
John N. Saddler ◽  
Makoto Yaguchi
Keyword(s):  
Molecular Mass ◽  
Trichoderma Harzianum ◽  
Thermal Tolerance ◽  
Specific Activity ◽  
Gene Products ◽  
Temperature Optimum ◽  
Ph Optimum ◽  
Polysulfone Membrane ◽  
Xylan Hydrolysis ◽  
Hydrolysis Of

Three of the xylanases produced by Trichoderma harzianum E58 passed through a polysulfone membrane with molecular mass cut-off of 10 000 daltons, even though their molecular mass had been estimated to be 20 000, 22 000, and 29 000 daltons. The 22 000 dalton xylanase was purified to homogeneity from a preparation containing a mixture of 22 000 and 20 000 dalton xylanase using a combination of hydrophobic column chromatography and chromatofocusing. This enzyme has a pI of 8.5, a specific activity of 0.28 U/mg, a temperature optimum between 45 and 50 °C, a pH optimum between 4.5 and 5.0, and the ability to cleave xylotriose. It differs from the other two xylanases by having a lower pI, a lower specific activity, and a lower thermal tolerance. All three xylanases are highly specific for xylan hydrolysis and they do not cleave xylobiose or release arabinose substituents from arabinoxylan. Their amino acid compositions suggest that they are three distinct gene products. The three enzymes are major components of the xylanolytic system of T. harzianum, which consists of at least two other xylanases and two β-xylosidases which are responsible for the release of arabinose substituents and the hydrolysis of xylobiose.

Purification of tributyrin esterase fromLactococcus lactissubsp.cremorisE8

1996 ◽  
Vol 63 (1) ◽  
pp. 131-140 ◽  
Author(s):  
Ross Holland ◽  
Tim Coolbear
Keyword(s):  
Molecular Mass ◽  
Lactococcus Lactis ◽  
Half Life ◽  
Esterase Activity ◽  
Terminal Sequence ◽  
Ph Optimum ◽  
Single Protein ◽  
A Subunit

SummaryA tributyrin esterase was purified fromLactococcus lactissubsp.cremorisE8 using FPLC chromatography. This was the major esterase activity observed in strain E8 and was associated with a single protein with a subunit molecular mass of 29 kDa and a holoenzyme of molecular mass 109 kDa. The enzyme was active against tributyrin andp-nitrophenyl butyrate. The N-terminal sequence of the enzyme was determined. The enzyme had a pH optimum in the neutral range, was stable on freezing at −20 °C, and had a half life of 1 h at 50 °C.

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 Purification and Characterization of Two Extremely Thermostable Enzymes, Phosphate Acetyltransferase and Acetate Kinase, from the Hyperthermophilic Eubacterium Thermotoga maritima

1999 ◽  
Vol 181 (6) ◽  
pp. 1861-1867 ◽  
Author(s):  
Anne-Katrin Bock ◽  
Jürgen Glasemacher ◽  
Roland Schmidt ◽  
Peter Schönheit
Keyword(s):  
Molecular Mass ◽  
Thermotoga Maritima ◽  
Enzyme Reaction ◽  
Acetyl Phosphate ◽  
Temperature Optimum ◽  
Terminal Amino Acid ◽  
Acetyl Coa ◽  
Ph Optimum ◽  
Terminal Amino ◽  
Phosphate Acetyltransferase

ABSTRACT Phosphate acetyltransferase (PTA) and acetate kinase (AK) of the hyperthermophilic eubacterium Thermotoga maritima have been purified 1,500- and 250-fold, respectively, to apparent homogeneity. PTA had an apparent molecular mass of 170 kDa and was composed of one subunit with a molecular mass of 34 kDa, suggesting a homotetramer (α4) structure. The N-terminal amino acid sequence showed significant identity to that of phosphate butyryltransferases fromClostridium acetobutylicum rather than to those of known phosphate acetyltransferases. The kinetic constants of the reversible enzyme reaction (acetyl-CoA + Pi ⇌ acetyl phosphate + CoA) were determined at the pH optimum of pH 6.5. The apparent Km values for acetyl-CoA, Pi, acetyl phosphate, and coenzyme A (CoA) were 23, 110, 24, and 30 μM, respectively; the apparentV max values (at 55°C) were 260 U/mg (acetyl phosphate formation) and 570 U/mg (acetyl-CoA formation). In addition to acetyl-CoA (100%), the enzyme accepted propionyl-CoA (60%) and butyryl-CoA (30%). The enzyme had a temperature optimum at 90°C and was not inactivated by heat upon incubation at 80°C for more than 2 h. AK had an apparent molecular mass of 90 kDa and consisted of one 44-kDa subunit, indicating a homodimer (α2) structure. The N-terminal amino acid sequence showed significant similarity to those of all known acetate kinases from eubacteria as well that of the archaeon Methanosarcina thermophila. The kinetic constants of the reversible enzyme reaction (acetyl phosphate + ADP ⇌ acetate + ATP) were determined at the pH optimum of pH 7.0. The apparent Km values for acetyl phosphate, ADP, acetate, and ATP were 0.44, 3, 40, and 0.7 mM, respectively; the apparent V max values (at 50°C) were 2,600 U/mg (acetate formation) and 1,800 U/mg (acetyl phosphate formation). AK phosphorylated propionate (54%) in addition to acetate (100%) and used GTP (100%), ITP (163%), UTP (56%), and CTP (21%) as phosphoryl donors in addition to ATP (100%). Divalent cations were required for activity, with Mn2+ and Mg2+ being most effective. The enzyme had a temperature optimum at 90°C and was stabilized against heat inactivation by salts. In the presence of (NH4)2SO4(1 M), which was most effective, the enzyme did not lose activity upon incubation at 100°C for 3 h. The temperature optimum at 90°C and the high thermostability of both PTA and AK are in accordance with their physiological function under hyperthermophilic conditions.

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.

Characterization of an enzyme from Rhizoctonia praticola which polymerizes phenolic compounds

1979 ◽  
Vol 25 (2) ◽  
pp. 229-233 ◽  
Author(s):  
Jean-Marc Bollag ◽  
Roy D. Sjoblad ◽  
Shu-Yen Liu
Keyword(s):  
Molecular Weight ◽  
Phenolic Compounds ◽  
Gel Electrophoresis ◽  
Polyacrylamide Gel Electrophoresis ◽  
Deae Cellulose ◽  
Phenol Oxidase ◽  
Temperature Optimum ◽  
Ph Optimum ◽  
Rhizoctonia Praticola

An extracellular phenol oxidase from the fungus Rhizoctonia praticola which polymerizes various xenobiotic phenols was isolated and characterized. The enzyme was purified by DEAE-cellulose and Sephadex G-200 chromatography followed by preparative polyacrylamide gel electrophoresis. Atomic absorption and EPR spectroscopy indicated the presence of copper, and SDS gel electrophoresis revealed a molecular weight of 78 000. With 2,6-dimethoxyphenol as substrate, the enzyme showed a pH optimum of 6.7–6.9, and a temperature optimum of 40 °C. According to these and additional characteristics it appears that the enzyme belongs to the class of laccases.

scholarly journals Purification and characterization of an antibacterial protein from dried fruiting bodies of the wild mushroom Clitocybe sinopica.

2010 ◽  
Vol 57 (1) ◽  
Author(s):  
Suyue Zheng ◽  
Qinghong Liu ◽  
Guoqing Zhang ◽  
Hexiang Wang ◽  
Tzi Bun Ng
Keyword(s):  
Antibacterial Activity ◽  
Molecular Mass ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Gel Filtration ◽  
Deae Cellulose ◽  
Exchange Chromatography ◽  
Fruiting Bodies ◽  
Wild Mushroom ◽  
Antibacterial Protein

A novel antibacterial protein with a molecular mass of 44 kDa has been isolated from dried fruiting bodies of the wild mushroom Clitocybe sinopica. Sodium dodecyl sulfate/polyacrylamide gel electrophoresis showed that the protein was composed of two subunits each with a molecular mass of 22 kDa. Its N-terminal amino-acid sequence, SVQATVNGDKML, has not been reported for other antimicrobial proteins. The purification protocol included ion exchange chromatography on DEAE-cellulose, CM-cellulose and Q-Sepharose, and gel filtration by fast protein liquid chromatography on Superdex 75. The antibacterial protein was adsorbed on all three ion exchangers. The antimicrobial activity profile of the protein against tested bacterial and fungal strains disclosed that it possessed potent antibacterial activity against Agrobacterium rhizogenes, A. tumefaciens, A. vitis, Xanthomonas oryzae and X. malvacearum with a minimum inhibitory concentration mostly below 0.6 microM. However, it had no antibacterial activity against Pseudomonas batatae, Erwinia herbicola, Escherichia coli, and Staphylococcus aureus, and no antifungal activity against Setosphaeria turcica, Fusarium oxysporum, Verticillium dahliae, Bipolaris maydis, and B. sativum. The antibacterial antivity against A. tumefaciens was stable after exposure to 20-60 degrees C for 30 min and to pH 4-9 for 1 h.

Sign in / Sign up

Export Citation Format

Share Document