scholarly journals Cloning, Expression and Characterization of the α-glucuronidase from the Hyperthermophile DictyoglomusturgidumDSM 6724Ô

2020 ◽  
Vol 1 (2) ◽  
pp. 34-47
Author(s):  
Phillip Brumm ◽  
Phillip Brumm ◽  
Dan Xie ◽  
Larry Allen ◽  
Dan Xie ◽  
...  

Conversion of biomass into fermentable sugars is a major requirement for successful and cost-effective biofuels production. The conversion of xylan to sugars requires multiple enzymes including α-glucuronidase. Here we report the cloning, expression, purification and characterization of the α-glucuronidase from Dictyoglomusturgidum(DtuAgu). DtuAgu is an intracellular protein of 685 amino acids and a predicted molecular weight of 79.4 kD. Enzymatic activity was optimum between pH 7.0 and 8.0 and at 85°C. The specific activity of the enzyme was 10 u/mg when measured using mixed aldouronic acids. The specific activity on isolated glucuronoxylan was approximately 20% of the value obtained with xylooligosaccharides. DtuAgu significantly improved xylan conversion to xylose when evaluated using two mixtures of thermostable bacterial enzymes and two sources of xylan. DtuAgu has the potential to be a key player in thermostable enzyme cocktails for the conversion to biomass to biofuels.α

Author(s):  
Baydaa A. Hassan ◽  
Mohammed A. Jebor ◽  
Zahra M. Ali

This study aims to purification and characterization of the glucose oxidase enzyme from Penicillium notatum, the enzyme was purified by ammonium sulfate precipitation (60%), dialysis and gel filtration chromatography using sephadex G-200, A trial for the purification of glucose oxidase using gel filtration technique resulted in one type of glucose oxidase with specific activity of (62.382 U/mg) with (7.385 folds) purification. the purified glucose oxidase had a maximum activity at pH = 5.5, 45 °C, glucose oxidase was stable with pH values ranging between (5 – 6) and the enzyme was maintained the activity when it incubated into (25 -35) °C for 15 minutes, analyses of the glucose oxidase for molecular weight was carried out by PAGE and SDS-PAGE electrophoresis, which revealed 78 KDa, also molecular weight of the glucose oxidase was achieved by gel filtration technique and was found 87 KDa this means that enzyme consisting of only one subunit, the Km and Vmax value of glucoamylase (B) were (19.6 mM, 7.5 mM/min ) respectively using different concentration of glucose.


Marine Drugs ◽  
2019 ◽  
Vol 17 (3) ◽  
pp. 185 ◽  
Author(s):  
Yangtao Fang ◽  
Suxiao Yang ◽  
Xiaodan Fu ◽  
Wancui Xie ◽  
Li Li ◽  
...  

Chondroitinase (ChSase), a type of glycosaminoglycan (GAG) lyase, can degrade chondroitin sulfate (CS) to unsaturate oligosaccharides, with various functional activities. In this study, ChSase AC II from a newly isolated marine bacterium Arthrobacter sp. CS01 was cloned, expressed in Pichia pastoris X33, purified, and characterized. ChSase AC II, with a molecular weight of approximately 100 kDa and a specific activity of 18.7 U/mg, showed the highest activity at 37 °C and pH 6.5 and maintained stability at a broad range of pH (5–7.5) and temperature (below 35 °C). The enzyme activity was increased in the presence of Mn2+ and was strongly inhibited by Hg2+. Moreover, the kinetic parameters of ChSase AC II against CS-A, CS-C, and HA were determined. TLC and ESI-MS analysis of the degradation products indicated that ChSase AC II displayed an exolytic action mode and completely hydrolyzed three substrates into oligosaccharides with low degrees of polymerization (DPs). All these features make ChSase AC II a promising candidate for the full use of GAG to produce oligosaccharides.


Blood ◽  
1995 ◽  
Vol 85 (12) ◽  
pp. 3503-3509 ◽  
Author(s):  
SK Ayesh ◽  
Y Azar ◽  
II Barghouti ◽  
JM Ruedi ◽  
BM Babior ◽  
...  

Earlier work has suggested that familial Mediterranean fever, an inherited disorder characterized by sporadic episodes of inflammation involving the pleural and peritoneal cavities and the joints, is caused by the lack of a C5a inactivator normally found in serosal fluid. We have purified this inactivator from ascites fluid and obtained a protein of molecular weight 53 to 56 kD with a specific activity 10,000- fold greater than the crude material. On Western blot, an inhibitory antibody recognized a single antigenic species at the same molecular weight. The enzyme had no activity against denatured bovine serum albumin. With recombinant C5a as substrate, the Km and Vm were 3.4 mumol/L and 52 nmol C5a/min/mg protein, respectively.


1979 ◽  
Author(s):  
M Ribieto ◽  
J Elion ◽  
D Labie ◽  
F Josso

For the purification of the abnormal prothrombin (Pt Metz), advantage has been taken of the existence in the family of three siblings who, being double heterozygotes for Pt Metz and a hypoprothrombinemia, have no normal Pt. Purification procedures included barium citrate adsorption and chromatography on DEAE Sephadex as for normal Pt. As opposed to some other variants (Pt Barcelona and Madrid), Pt Metz elutes as a single symetrical peak. By SDS polyacrylamide gel electrophoresis, this material is homogeneous and appears to have the same molecular weight as normal Pt. Comigration of normal and abnormal Pt in the absence of SDS, shows a double band suggesting an abnormal charge for the variant. Pt Metz exhibits an identity reaction with the control by double immunodiffusion. Upon activation by factor Xa, Pt Metz can generate amydolytic activity on Bz-Phe-Val-Arg-pNa (S2160), but only a very low clotting activity. Clear abnormalities are observed in the cleavage pattern of Pt Metz when monitored by SDS gel electrophoresis. The main feature are the accumulation of prethrombin l (Pl) and the appearance of abnormal intermediates migrating faster than Pl.


1984 ◽  
Vol 62 (5) ◽  
pp. 276-279 ◽  
Author(s):  
C. H. Lin ◽  
W. Chung ◽  
K. P. Strickland ◽  
A. J. Hudson

An isozyme of S-adenosylmethionine synthetase has been purified to homogeneity by ammonium sulfate fractionation, DEAE-cellulose column chromatography, and gel filtration on a Sephadex G-200 column. The purified enzyme is very unstable and has a molecular weight of 120 000 consisting of two identical subunits. Amino acid analysis on the purified enzyme showed glycine, glutamate, and aspartate to be the most abundant and the aromatic amino acids to be the least abundant. It possesses tripolyphosphatase activity which can be stimulated five to six times by S-adenosylmethionine (20–40 μM). The findings support the conclusion that an enzyme-bound tripolyphosphate is an obligatory intermediate in the enzymatic synthesis of S-adenosylmethionine from ATP and methionine.


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