scholarly journals Purification and characterization of the heat-stable serine proteinase from Thermomonospora fusca YX

1987 ◽  
Vol 246 (2) ◽  
pp. 511-517 ◽  
Author(s):  
T W Gusek ◽  
J E Kinsella

The proteinase secreted from Thermomonospora fusca YX grown on cellulose was purified by (NH4)2SO4 fractionation and cation-exchange chromatography. The isolated proteinase readily hydrolysed several proteins and demonstrated activity towards casein from 35 to 95 degrees C (at pH 8.0) with maximum activity at 80 degrees C. It exhibited broad pH and ionic-strength optima centered at pH 9.0 and 0.2 M-NaCl respectively, and it retained high activity in the presence of 2% (w/v) SDS, 20 mM-dithiothreitol and 1.0 M-NaCl. The proteinase, which was fully inhibited by phenylmethanesulphonyl fluoride, had an Mr of 14,500 and an isoelectric point at 9.21. A measurement of proteinase thermal stability demonstrated a T50% (15 min) of 85 degrees C at pH 4.5.

1986 ◽  
Vol 53 (3) ◽  
pp. 457-466 ◽  
Author(s):  
David J. Fairbairn ◽  
Barry A. Law

SUMMAEYPseudomonas fluorescensNCDO 2085 produced a single heat-stable extracellular proteinase in Na caseinate medium at 20 °C and pH 7·0. The proteinase was purified to electrophoretic homogeneity using chromatofocusing, gel filtration and ion-exchange chromatography. The purification procedure resulted in a 158-fold increase in the specific activity and a yield of 3·5% of the original activity. The enzyme is a metalloproteinase containing Zn and Ca, with an isoelectric point at 5·40±0·05 and a mol. wt of 40200±2100. It is heat-stable having D-values at 74 and 140 °C of 1·6 and 1·0 min respectively; 40 and 70% of the original activity remained after HTST (74 °C/17 s) and ultra high temperature (140°C/4 s) treatments respectively. The amino acid composition of the proteinase was determined and compared with those from otherPseudomonasspp.


2012 ◽  
Vol 192 ◽  
pp. 285-288 ◽  
Author(s):  
Shan Shan Liu ◽  
Li Li Wang ◽  
Lin Yuan

The purification and characterization of an alkaline protease produced by Bacillus alcalophilus were investigated. The enzyme was purified in two steps: concentrating the crude enzyme using ammonium sulfate precipitation, followed by cation-exchange chromatography. The purified protease had a molecular mass of approximately 28 kDa, was highly active over an alkaline pH range of 10.0 to 11.0, and remained stable over a pH range of 7.0 to 12.0. The optimum temperature for the enzyme activity was found to be 40~60°C, while the thermotolerance of the enzyme was poor. Therefore, these characteristics of the protease indicate its potential for a wide range of commercial applications.


1987 ◽  
Vol 248 (1) ◽  
pp. 223-228 ◽  
Author(s):  
H G Hergenhahn ◽  
A Aspan ◽  
K Söderhäll

Crayfish plasma was found to contain a proteinase inhibitor, which was purified to apparent homogeneity by acid precipitation, affinity chromatography on concanavalin A-Sepharose and hydrophobic-interaction chromatography. The inhibitor is a monomeric protein with an Mr of about 155,000 and a pI in the range 4.6-4.8. It is heat-stable and tolerant to low pH. It inhibits the serine proteinases trypsin and chymotrypsin, but not thrombin or subtilisin. Furthermore, it is efficient in decreasing the activity of a proteinase from crayfish haemolymph that is involved in the activation cascade of pro-phenol oxidase and can also block pro-phenol oxidase activation by this serine proteinase. This cascade is believed to play a central role in the recognition mechanism of non-self material in crustaceans and insects. The data presented give some evidence that the new proteinase inhibitor is involved in the regulation of this system.


2016 ◽  
Vol 9 (1) ◽  
pp. 1 ◽  
Author(s):  
B. S. Fagbohunka ◽  
R. E. Okonji ◽  
Ayinla Zainab Adenike

Cellulase enzyme was purified and characterized from termite soldiers (Ametermes eveuncifer) using 70% ammonium sulphate precipitation, ion exchange chromatography and affinity chromatography. The enzyme isolated had a specific activity of 5.04 U/mg with a percentage yield of 11.7%. The enzyme showed maximum activity at 500C and pH 8. The enzyme was not inhibited by Ba2+ at a concentration of 1mM and Pb2+ at 10 mM concentration but was inhibited by other metal ions at 1 mM and 10 mM concentrations of their salts (NaCl, KCl, MnCl2, and NiCl2),


1999 ◽  
Vol 54 (3-4) ◽  
pp. 181-185 ◽  
Author(s):  
Akira Oikawa ◽  
Kenkichi Ebisui ◽  
Masayuki Sue ◽  
Atsushi Ishihara ◽  
Hajime Iwamura

Occurrence and properties of hydroxamic acid glucoside glucosidase were investigated in 10-day-old, autotrophic maize (Zea mays L.) in which 2,4-dihydroxy-7-methoxy-1,4- benzoxazin-3-one glucoside (DIMBOA-G) is a major benzoxazinone component. Crude extracts of both leaves and roots showed glucosidase activity for both DIMBOA-G and 2,4- dihydroxy-1,4-benzoxazin-3-one glucoside (DIBOA-G). A cation-exchange chromatography after cryoprecipitation of the extract from leaves gave a peak with both activities, and further purification by ion-exchange and hydroxyapatite chromatography gave a fraction with an apparent homogeneity, the purification being 560 fold. The Km values (mᴍ) of the purified glucosidase were 0.16 for DIMBOA-G, 0.68 for DIBOA-G and 2.96 for p-nitrophenyl-β-ᴅ-glucopyranoside. The activity on salicin and esculin was too low to be detected. The data indicate that a glucosidase specific for DIMBOA-G comes into contact with constitutive benzoxazinone glucosides producing defensive aglycone when plants are damaged by microbial or insect attacks.


2005 ◽  
Vol 69 (1) ◽  
pp. 38-44 ◽  
Author(s):  
Kazumi HIRAGA ◽  
Yasushi NISHIKATA ◽  
Sirilak NAMWONG ◽  
Somboon TANASUPAWAT ◽  
Katsumi TAKADA ◽  
...  

Author(s):  
Graciella da Silva Campello ◽  
Renata Aguirre Trindade ◽  
Tatiane Vieira Rêgo ◽  
Janaína Fernandes de Medeiros Burkert ◽  
Carlos André Veiga Burkert

Abstract The main goal of this study was to investigate the immobilization of commercial ß-galactosidase from Kluyveromyces lactis (Lactozym®) on Eupergit® C. A Plackett-Burman design was proposed. The ionic strength and pH were the variables that presented significant effect (p<0.1) on immobilization. The increase in the ionic strength from 0.1 to 1.5 M and the increase in pH from 6.6 to 7.4 represented an increase of 28.56% and a reduction of 18.19% in the immobilization yield, respectively. At 25°C, pH 6.6, ionic strength of 1.5 M, immobilization for 8 h, 1 mM of divalent magnesium ion and 0.4 mL of enzyme added, reached 85% immobilization yield. The free and immobilized enzymes were characterized. pH and temperature profiles showed maximum activity at pH 6.6 and 45°C, for both free and immobilized enzymes. There was a gain in thermal stability with enzyme immobilization and there was an increase of about four times in the half-life of the immobilized derivative at 45°C (from 0.43 h to 1.78 h). This greater thermal stability was also made clear through the calculation of thermodynamic parameters (ΔH, ΔG and ΔS). Km values, 30.33 mM and 104.00 mM for free and immobilized enzymes, respectively, represented a reduction in substrate affinity after immobilization, possibly owing to stereo-conformational factors. In a batch reactor for lactose hydrolysis from cheese whey, an increase in lactose conversion with immobilization was observed at 40°C and 45°C (90.43% and 65.36%, respectively) in relation to the free enzyme (84.17% and 39.58%, respectively).


2015 ◽  
Vol 87 (17) ◽  
pp. 9084-9092 ◽  
Author(s):  
Gomathinayagam Ponniah ◽  
Adriana Kita ◽  
Christine Nowak ◽  
Alyssa Neill ◽  
Yekaterina Kori ◽  
...  

2011 ◽  
Vol 63 (3) ◽  
pp. 747-756 ◽  
Author(s):  
A.K.M. Asaduzzaman ◽  
Habibur Rahman ◽  
Tanzima Yeasmin

An acid phosphatase has been isolated and purified from an extract of a germinating black gram seedling. The method was accomplished by gel filtration of a germinating black gram seedling crude extract on sephadex G-75 followed by ion exchange chromatography on DEAE cellulose. The acid phosphatase gave a single band on SDS-polyacrylamide slab gel electrophoresis. The molecular weight of the acid phosphatase determined by SDS-polyacrylamide slab gel electrophoresis was estimated to be 25 kDa. The purified enzyme showed maximum activity at pH 5 and at temperature of 55?C. Mg2+, Zn2+ and EDTA had an inhibitory effect on the activity of the acid phosphatase. Black gram seedling acid phosphatase was activated by K+, Cu2+ and Ba2+. The Km value of the enzyme was found to be 0.49 mM for pNPP as substrate.


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