Purification and the effect of peptide N-glycosidase F on lysosomal membrane-bound glucocerebrosidase from human cultured fibroblasts

1991 ◽  
Vol 69 (8) ◽  
pp. 551-556 ◽  
Author(s):  
Francis Y. M. Choy ◽  
Mary Woo

Glucocerebrosidase was purified from human cultured dermal fibroblasts more than 2200-fold to apparent homogeneity using high performance Alkyl-Superose HR 5/5 hydrophobic interaction and Bio-Sil TSK-250 gel permeation column chromatography. Sodium dodecyl sulfate – polyacrylamide gel electrophoresis and protein staining of the catalytically active and concentrated enzyme fractions from the gel permeation columns revealed the presence of one band of Mr 64 000. The glucocerebrosidase preparation purified to homogeneity was digested with peptide N-glycosidase F that cleaves N-linked oligosaccharide structures from glycoproteins. The molecular weight of glucocerebrosidase after digestion with peptide N-glycosidase F was reduced to Mr 57 000, suggesting that the mature enzyme is a glycoprotein and that N-linked oligosaccharide constitutes a minimum of about 10% of the total molecular weight of the polypeptide. These findings are compatible with the hypothesis that glucocerebrosidase was initially synthesized as a precursor polypeptide which was subsequently glycosylated to become the mature enzyme.Key words: glucocerebrosidase, purification, deglycosylation, N-glycosidase F, fibroblasts.

1977 ◽  
Vol 55 (9) ◽  
pp. 958-964 ◽  
Author(s):  
M. P. C. Ip ◽  
R. J. Thibert ◽  
D. E. Schmidt Jr.

Cysteine-glutamate transaminase (cysteine aminotransferase; EC 2.6.1.3) has been purified 149-fold to an apparent homogeneity giving a specific activity of 2.09 IU per milligram of protein with an overall yield of 15%. The isolation procedures involve the preliminary separation of a crude rat liver homogenate which was submitted sequentially to ammonium sulfate fractionation, TEAE-cellulose column chromatography, ultrafiltration, and isoelectrofocusing. The final product was homogenous when examined by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate (SDS). A minimal molecular weight of 83 500 was determined by Sephadex gel chromatography. The molecular weight as estimated by polyacrylamide gel electrophoresis in the presence of SDS was 84 000. The purified enzyme exhibited a pH optimum at 8.2 with cysteine and α-ketoglutarate as substrates. The enzyme is inactivated slowly when kept frozen and is completely inactivated if left at room temperature for 1 h. The enzyme does not catalyze the transamination of α-methyl-DL-cysteine, which, when present to a final concentration of 10 mM, exhibits a 23.2% inhibition of transamination of 30 mM of cysteine. The mechanism apparently resembles that of aspartate-glutamate transaminase (EC 2.6.1.1) in which the presence of a labile hydrogen on the alpha-carbon in the substrate is one of the strict requirements.


1988 ◽  
Vol 66 (1) ◽  
pp. 32-39 ◽  
Author(s):  
Eduardo T. Cánepa ◽  
Elena B.C. Llambías

Pig liver ferrochelatase was purified 465-fold with about 30% yield, to apparent homogeneity, by a procedure involving solubilization from mitochondria, ammonium sulfate fractionation, and Sephacryl S-300 chromatography. The fraction of each purification step had cobaltochelatase as well as ferrochelatase activity. A purified protein of molecular weight 40 000 was found by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate. A molecular weight of approximately 240 000 was obtained by Sephacryl S-300 chromatography. Both activities of the purified fraction increased linearly with time until 2 h. but nonlinear plots were obtained with increasing concentrations of protein. Their optimum pH values were similar. Km values were, for ferrochelatase activity, 23.3 μM for the metal and 30.3 μM for mesoporphyrin. and for cobaltochelatase activity. 27 and 45.5 μM, respectively. Fe2+ and Co2+ each protected against inactivation by heat. Pb2+, Zn2+, Cu2+, or Hg2+ inhibited both activities, while Mn2+ slightly activated; Mg2+ had no effect, at the concentrations tested. There appeared to be an involvement of sulfhydryl groups in metal insertion. Lipids, in correlation with their degree of unsaturation, activated both purified activities; phospholipids also had activation effects. We conclude that a single protein catalyzes the insertion of Fe2+ or Co2+ into mesoporphyrin.


1981 ◽  
Vol 195 (2) ◽  
pp. 389-397 ◽  
Author(s):  
D A Wiginton ◽  
M S Coleman ◽  
J J Hutton

Adenosine deaminase was purified 3038-fold to apparent homogeneity from human leukaemic granulocytes by adenosine affinity chromatography. The purified enzyme has a specific activity of 486 mumol/min per mg of protein at 35 degrees C. It exhibits a single band when subjected to sodium dodecyl sulphate/polyacrylamide-gel electrophoresis, non-denaturing polyacrylamide-gel electrophoresis and isoelectric focusing. The pI is 4.4. The enzyme is a monomeric protein of molecular weight 44000. Both electrophoretic behaviour and molecular weight differ from those of the low-molecular-weight adenosine deaminase purified from human erythrocytes. Its amino acid composition is reported. Tests with periodic acid-Schiff reagent for associated carbohydrate are negative. Of the large group of physiological compounds tested as potential effectors, none has a significant effect. The enzyme is specific for adenosine and deoxyadenosine, with Km values of 48 microM and 34 microM respectively. There are no significant differences in enzyme function on the two substrates. erythro-9-(2-Hydroxy non-3-yl) adenine is a competitive inhibitor, with Ki 15 nM. Deoxycoformycin inhibits deamination of both adenosine and deoxyadenosine, with an apparent Ki of 60-90 pM. A specific antibody was developed against the purified enzyme, and a sensitive radioimmunoassay for adenosine deaminase protein is described.


1984 ◽  
Vol 62 (1) ◽  
pp. 28-33 ◽  
Author(s):  
Ron M. Fourney ◽  
Shashikant B. Joshi ◽  
Ming H. Kao ◽  
Choy L. Hew

The heterogeneity of Newfoundland winter flounder antifreeze polypeptides was analyzed by reverse phase high performance liquid chromatography and by sodium dodecyl sulfate polyacrylamide gel electrophoresis. Seven antifreeze polypeptide components could be readily demonstrated. Five of the components were similar in molecular weight (3300) and amino acid composition. Two of the antifreeze polypeptide components were larger (4500) and contained valine. The two major components (components 6 and 8) were identical to those reported earlier from our laboratories.


1990 ◽  
Vol 258 (3) ◽  
pp. E451-E458
Author(s):  
S. Kim ◽  
M. Hosoi ◽  
F. Ikemoto ◽  
K. Murakami ◽  
Y. Ishizuka ◽  
...  

Highly purified recombinant human prorenin, labeled with 125I (125I-prorenin), was intravenously given to monkeys to examine the possible in vivo conversion of this prorenin to renin. 125I-prorenin and 125I-renin were detected using specific anti-prorenin prosegment antibody and anti-renin antibody, respectively. The plasma disappearance of immunoreactive 125I-prorenin in marmosets showed two exponential components with a half-life of 10.4 +/- 0.2 min for the rapid component and 165.7 +/- 12.6 min for the slow component. Fifteen minutes after the injection of 125I-prorenin, 38.7 +/- 2.8 and 3.9 +/- 0.5% of the administered dose accumulated in the liver and kidney, respectively. Less than 1% of the dose injected distributed in the other organs, including the brain, submandibular gland, lung, heart, aorta, adrenal gland, spleen, uterus, ovary, and testis. Thus the labeled prorenin was predominantly taken up by the liver and kidney. Analysis of liver and kidney extracts and plasma, by both gel permeation high-performance liquid chromatography and sodium dodecyl sulfate-polyacrylamide gel electrophoresis, demonstrated that 125I-prorenin (Mr = 46,000) taken up by the liver and kidney was significantly converted to 125I-renin (Mr = 42,000), whereas only a negligible amount of 125I-renin (Mr = 42,000) was present in the plasma. Although there seems to be no activation of prorenin in the blood circulation, prorenin does seem to be activated by the liver and kidney.


Blood ◽  
1988 ◽  
Vol 71 (2) ◽  
pp. 480-487
Author(s):  
N Yoshida ◽  
K Ota ◽  
M Moroi ◽  
M Matsuda

A gamma-chain variant with an apparently higher molecular weight than the normal gamma-chain was detected in a new congenital abnormal fibrinogen with impaired polymerization of the fibrin monomer and with normal release of fibrinopeptides A and B in a 51-year-old male. Purified fibrinogen analyzed on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) under the reduced condition in the system of Laemmli contained two protein bands in the gamma-chain region (molecular weight, 50,500 as compared with 50,000 for the normal), both with normal crosslinking ability. The presence of two types of gamma- chains was more clearly detected when reduced and carboxymethylated fibrinogen was analyzed by SDS-PAGE or when reduced fragment D2 was analyzed on SDS-PAGE followed by Western blotting, and identified by positive staining for anti gamma-chain monoclonal antibody. Cyanogen bromide- or lysylendopeptidase-cleavage of purified gamma-chains analyzed on reverse-phase high performance liquid chromatography showed the decrease of one peptide compared with the normal and the appearance of an abnormal peptide peak. Amino acid sequence analysis demonstrated that the gamma arginine-275 of gamma-chain variant was replaced by a cysteine. These data suggest that some regions or conformations containing gamma 275 will affect the polymerization of fibrin monomers. The propositus' two daughters had the same abnormal fibrinogen. This unique inherited abnormal fibrinogen was designated as fibrinogen Tochigi, and the gamma-chain variant as gamma Tochigi.


Author(s):  
Abimbola Olajide ◽  
Felicia C. Adesina ◽  
Abiodun A. Onilude

Aim: The study aimed at producing and purifying thermostable and alkalitolerant microbial arabinofuranosidase using local Palm Kernel Cake (PKC) as substrate. Study Design: This is an experimental design in which samples were collected thrice and  subjected to laboratory analyses from which quantitative data were obtained and analysed. Place and Duration of Study: Ibadan, Nigeria, Five months. Methodology: Bacterial strains were isolated from degrading PKC by serial dilution and pour plate technique on formulated Modified Basal Salt Agar Medium and incubated at 50°C for enzyme activity screening. Plates were afterwards flooded with 1% congo red solution for visualization of hydrolysis zone. Its arabinofuranosidase activity was optimized in solid state fermentation in PKC. Production temperature, pH, moisture content, inoculum size and agitation were studied for optimization test. Optimal production temperature and pH for arabinofuranosidase by isolate was 45°C and pH 9. Produced arabinofuranosidase was purified to apparent homogeneity with ammonium sulphate precipitation, dialysis and column chromatography techniques. Stability of arabinofuranofuranosidase obtained to temperature, pH, substrate concentration and some ions was determined as well as its molecular weight using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Results: Isolate with highest arabinofuranosidase activity was selected and identified as Streptomyces lividus. Purity level attained was 16.36 fold. Enzyme had a specific activity of 25.4 U/mg, and total enzyme activity of 13.2 U.  Molecular weight of enzyme appeared as a band of 30 kDa. Purified arabinofuranosidase enzyme revealed optimum temperature and pH as 60oC and 9 respectively. Enzyme was stable over a broad pH range of 3-11, and temperature of 30-80oC. Residual activity after incubating for 1 hour at 70oC was 64%. Enzyme kinetics studies showed Km and Vmax values for P-nitrophenyl arabinofuranoside were 2.3mM and 0.7U/min respectively. Conclusion: Apart from Solid State Fermentation (SSF) of PKC being a potential fermentation technique for production of arabinofuranosidase by Streptomyces lividus, the enzyme was highly stable.


1996 ◽  
Vol 42 (1) ◽  
pp. 1-5 ◽  
Author(s):  
Edivaldo Ximenes Ferreira Filho

The thermophilic fungus Humicola grisea var. thermoidea produced β-glucosidase activity when grown in a solid-state culture on wheat bran as carbon source. A β-glucosidase was purified to apparent homogeneity by ultrafiltration, gel filtration chromatography on Sephacryl S-100, and ion-exchange chromatography on S-Sepharose, as judged by sodium dodecyl sulfate – polyacrylamide gel electrophoresis (SDS–PAGE) on a 12.5% (w/v) slab gel. The enzyme had a molecular mass of 82 and 156 kDa, as estimated by SDS–PAGE and gel filtration on a high performance liquid chromatographic column, respectively, suggesting that the native enzyme may consist of two identical subunits. The purified enzyme was thermostable at 60 °C for 1 h with a half-life of 15 min at 65 °C, and displayed optimum activity at 60 °C and a pH range of 4.0–4.5. The Kmand Vmaxvalues for p-nitrophenyl β-D-glucopyranoside were determined to be 0.316 mM and 0.459 IU∙mL−1, respectively. D-Glucose, D-gluconic acid lactone, Hg2+, Cu2+, and Mn2+inhibited β-glucosidase activity. The enzyme activity was competitively inhibited by D-glucose (Ki = 0.6 mM). The purified enzyme was very active against cellobiose and p-nitrophenyl β-D-glucopyranoside.Key words: Humicola, β-glucosidase, purification, characterization.


Blood ◽  
1988 ◽  
Vol 71 (2) ◽  
pp. 480-487 ◽  
Author(s):  
N Yoshida ◽  
K Ota ◽  
M Moroi ◽  
M Matsuda

Abstract A gamma-chain variant with an apparently higher molecular weight than the normal gamma-chain was detected in a new congenital abnormal fibrinogen with impaired polymerization of the fibrin monomer and with normal release of fibrinopeptides A and B in a 51-year-old male. Purified fibrinogen analyzed on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) under the reduced condition in the system of Laemmli contained two protein bands in the gamma-chain region (molecular weight, 50,500 as compared with 50,000 for the normal), both with normal crosslinking ability. The presence of two types of gamma- chains was more clearly detected when reduced and carboxymethylated fibrinogen was analyzed by SDS-PAGE or when reduced fragment D2 was analyzed on SDS-PAGE followed by Western blotting, and identified by positive staining for anti gamma-chain monoclonal antibody. Cyanogen bromide- or lysylendopeptidase-cleavage of purified gamma-chains analyzed on reverse-phase high performance liquid chromatography showed the decrease of one peptide compared with the normal and the appearance of an abnormal peptide peak. Amino acid sequence analysis demonstrated that the gamma arginine-275 of gamma-chain variant was replaced by a cysteine. These data suggest that some regions or conformations containing gamma 275 will affect the polymerization of fibrin monomers. The propositus' two daughters had the same abnormal fibrinogen. This unique inherited abnormal fibrinogen was designated as fibrinogen Tochigi, and the gamma-chain variant as gamma Tochigi.


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