scholarly journals Purification of two hexosaminidases from human kidney

1977 ◽  
Vol 163 (1) ◽  
pp. 133-140 ◽  
Author(s):  
D V Marinkovic ◽  
J N Marinkovic

Hexosaminidase forms A and B were isolated from human kidney in a homogeneous state as demonstrated by electrophoretic and enzymic criteria. The enzymes were stable for at least 18 months when stored at -20 degrees C in 0.025 M-phosphate buffer, pH 6.5. The molecular weights of forms A and B were estimated by gel filtration to be 111 000 +/- 1500 and 114 000 +/- 1600 respectively. The molecular weights of hexosamidase A and B subunits were determined by using polyacrylamide-gel electrophoresis in the presence of sodium dodecyl sulphate. Hexosaminidase A dissociated into one subunit with mol.wt. 68 000. Hexosaminidase B dissociated into three subunits with mol. wts. 100 000, 68 000 and 37000 respectively, and one protein band of mol.wt. 140 000. After treatment of hexosaminidases A and B with iodoacetic acid, the molecular weights of the carboxymethylated polypeptide subunits were also estimated. Carboxymethylated hexosaminidase A dissociated into one major subunit of mol.wt. 18 000 and two other protein bands of mol.wts. 65 000 and 100 000. Carboxymethylated hexosaminidase B dissociated into one major subunit for mol.wt. 19 000 and an additional band of mol.wt. 37 000. The Km of the enzymes for the synthetic substrate p-nitrophenyl 2-acetamido-2-deoxy-beta-D-glucopyranoside was 0.8 mM. Both enzymes were inhibited or activated by various metal ions. Double pH optima for the enzymes were found at pH 4.5 and 4.8.

1983 ◽  
Vol 209 (2) ◽  
pp. 471-479 ◽  
Author(s):  
S T George ◽  
A S Balasubramanian

N alpha-Acetylenkephalin carboxypeptidase was co-purified with N-acetyltyrosine deacetylase from monkey kidney. Almost 90% of the activity from the homogenate was recovered in a high-speed supernatant without the use of detergents. The crucial steps in the purification were Cibacron Blue F3GA-Sepharose chromatography (involving negative and positive binding sequentially) and metal chelate affinity chromatography. The purified enzyme showed three bands on gel electrophoresis under non-denaturing conditions. All the three bands exhibited both N-acetyltyrosine deacetylase and N-acetylenkephalin carboxypeptidase activity, indicating their co-migration, Sodium dodecyl sulphate/polyacrylamide-gel electrophoresis in the presence and absence of 2-mercaptoethanol gave a single protein band of mol.wt. 34 000. The native enzyme was a dimer of mol.wt. 66 000 as observed on Bio-Gel P-300 gel filtration. The carboxypeptidase removed two amino acids from the C-terminal end of either N-acetyl[Met5]- or N-acetyl[Leu5]-enkephalin. Non-acetylated enkephalins were less active as substrates. Peptides with their carboxy end blocked were inactive as substrates. Models suggested for carboxypeptidase A [Hartsuck & Lipscomb (1971) Enzymes 3, 1-56] support the idea that the kidney N-acetylated aromatic amino acid deacetylase or acylase III [Endo (1978) Biochim. Biophys. Acta 523, 207-217] can act as a carboxypeptidase on peptides having hydrophobic amino acids at the C-terminal end.


1974 ◽  
Vol 77 (3) ◽  
pp. 485-497 ◽  
Author(s):  
P. A. Torjesen ◽  
T. Sand ◽  
N. Norman ◽  
O. Trygstad ◽  
I. Foss

ABSTRACT Highly purified human LH, FSH and TSH were isolated from batches of 300 frozen pituitary glands (200 g) by pH, acetone and ethanol fractionation, Sephadex gel filtration, ion-exchange chromatography on DEAE-cellulose and CM-Sephadex, and preparative polyacrylamide-gel electrophoresis. Sodium dodecyl-sulphate (SDS) polyacrylamide gel electrophoresis was used in order to check the purity, the identity and the molecular weight of the purified LH, FSH and TSH. This procedure showed that the hormone preparations consisted of two subunits with molecular weights of: LH: 21 300 and 17 900, FSH: 22 100 and 18 300 and TSH: 20 800 and 16 400. The purity of the hormone preparations was also evaluated by analytical disc electrophoresis at pH 8.9. The purified hormone preparations had radioimmunological activity as follows: LH: 20 000 IU/mg, FSH: 16 500 IU/mg and TSH: 5 IU/mg. All preparations had high biological potency.


1978 ◽  
Vol 171 (2) ◽  
pp. 435-444 ◽  
Author(s):  
D Propping ◽  
L J D Zaneveld ◽  
P F Tauber ◽  
G F B Schumacher

Two plasminogen activators (1 and 2) were isolated from human seminal plasma by hiigh-speed centrifugation, Sephadex-gel filtration and ion-exchange chromatography. The activators were shown to be homogeneous by polyacrylamide-disc -gel electrophoresis at pH 8.3 and 4.5, and by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis. The molecular weights of activators 1 and 2 were estimated as 69 000 and 74 000. Their amino acid compositions are very similar, both being high in aspartic acid, glutamic acid, serine, glycine and leucine, and low in methionine, tryptophan, tyrosine, isoleucine and histidine. Activators 1 and 2 each possess 16 cysteine residues. Both activators have isoelectric points of approx. 7.0, are stable over a wide pH range at temperatures up to 60 degrees C, but lose activity at higher temperatures, particularly under very basic or acidic conditions. They are not inhibited by EDTA, Mg2+ and Ca2+ at 10 mM concentrations, but their activity decreases on addition of 10 mM-cysteine or Fe2+ and 6-aminohexanoate or sera from pregnant women. The precipitin band formed between urokinase and its antiserum is continuous with the precipitin bands formed between the seminal plasminogen activators and the urokinase antiserum. Antisera to urokinase inhibit both the activity of urokinase and the seminal plasminogen activators.


2020 ◽  
Author(s):  
Rômulo Leão Silva Neris ◽  
Ajuni Kaur ◽  
Aldrin V. Gomes

ABSTRACTThe most widely used Western blotting protein standards are prestained proteins of known molecular mass (kDa). They are also utilized for sodium dodecyl sulphate (SDS) Polyacrylamide Gel Electrophoresis (PAGE) to determine the molecular mass of proteins separated by electrophoresis. The objective of this study was to assess the reliability of different commercially available protein standards in predicting accurate protein molecular weights. We performed this experiment by running Criterion TGX gels with five prestained protein standards (Thermo Fisher SeeBlue Plus 2, Bio-Rad Precision Plus Protein Dual-color, Thermo Fisher Spectra Multi-color, Novex-Sharp Pre-stained, and Invitrogen iBright Pre-Stained). To evaluate their accuracy, we utilized highly purified Bovine Serum Albumin (BSA, 66.44 kDa) and Cytochrome C (Cyto C, 11.62 kDa). We also made use of the dimers of BSA (132.88 kDa) and Cyt C (23.24 kDa) that are present on SDS-PAGE gels. Our results suggest that three of the standards were less accurate at higher molecular masses with the iBright marker having the highest error in determining the expected 132.88 kDa molecular weight. The SeeBlue Plus 2 was accurate at identifying the 132.88 kDa molecular weight protein band but was less reliable for the three other lower molecular weight proteins. These findings have significant implications for the determination of protein masses because researchers rely on these standards to evaluate the molecular masses of their protein(s). We suggest that at least two different protein standards should be initially used in electrophoresis gels and for Western blotting in order to get accurate protein molecular weight results.


1980 ◽  
Vol 189 (1) ◽  
pp. 185-188 ◽  
Author(s):  
M J Prigent ◽  
R Bourrillon

The subunit of the Vicia graminea lectin with blood-group-N specificity was examined by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis and gel filtration in 6M-guanidinium chloride, and its molecular weights was found to be 25 000. The unique N-terminal sequence fof the first nine residues of the lectin confirmed that Vicia lectin consists of four identical chains non-covalently linked. Finally the microheterogeneity of the lectin shown by analytical isoelectric focusing is discussed.


1992 ◽  
Vol 38 (5) ◽  
pp. 436-442 ◽  
Author(s):  
Devyani Dey ◽  
Jyoti Hinge ◽  
Abhay Shendye ◽  
Mala Rao

An alkalophilic thermophilic Bacillus sp. (NCIM 59) isolated from soil produced two types of cellulase-free xylanase at pH 10 and 50 °C. The two enzymes (xylanase I and II) were purified to homogeneity by ethanol precipitation followed by Bio-Gel P-10 gel filtration and preparative polyacrylamide gel electrophoresis. The molecular weights of xylanase I and II were estimated to be 35 000 and 15 800, respectively, by sodium dodecyl sulfate gel electrophoresis. The enzymes exhibited immunological cross-reactivity and were glycoproteins. They had similar temperature (50–60 °C) and pH (6) optima. Both xylanases were stable at 50 °C at pH 7 for 4 days. However, xylanase I was comparatively more stable than xylanase II at 60 °C. The isoelectric points of xylanase I and II were 4 and 8, respectively. The apparent Km values, using xylan as substrate, were 1.58 and 3.5 mg/mL, and Vmax values were 0.0172 and 0.742 μmol∙min−1∙mg−1, respectively. Both xylanases were inhibited by N-bromosuccinimide, suggesting the involvement of tryptophan in the active site. The hydrolysis patterns demonstrated that the xylanases were endoenzymes. Xylanase I and II yielded mainly xylobiose, xylotriose, and higher xylooligosaccharides, with traces of xylose from xylan. Key words: cellulase-free xylanase, alkalophilic thermophilic Bacillus sp., enzyme purification, characterization.


1982 ◽  
Vol 47 (01) ◽  
pp. 014-018 ◽  
Author(s):  
H Sumi ◽  
N Toki ◽  
S Takasugi ◽  
S Maehara ◽  
M Maruyama ◽  
...  

SummaryPapain treatment of human urinary trypsin inhibitor (UTI67; mol. wt. 43,000 by SDS-polyacrylamide gel electrophoresis, specific activity 1,897 U/mg protein) produced four new protease inhibitors, which were highly purified by gel chromatography on Sephadex G-100 and isoelectric focusing. The purified inhibitors (UTI26, UTI9-I, UTI9-II, and UTI9-III) were shown to be homogeneous by polyacrylamide disc gel electrophoresis, and had apparent molecular weights of 26,000, 9,000, 9,000, and 9,800, respectively, by sodium dodecyl sulfate gel electrophoresis. During enzymatic degradation of UTI67, the amino acid compositions changed to more basic, and the isoelectric point increased from pH 2.0 (UTI67) to pHs 4.4, 5.2, 6.6, and 8.3 (UTI26, UTI9-I, UTI9-II, and UTI9-III), respectively. Both the parent and degraded inhibitors had anti-plasmin activity as well as antitrypsin and anti-chymotrypsin activities. Much higher anti-plasmin/anti-trypsin and anti-plasmin/anti-chymotrypsin activities were observed in the degraded inhibitors than in the parent UTI67. They competitively inhibited human plasmin with Ki values of 1.13 X 10-7 - 2.12 X 10-6 M (H-D-Val-Leu-Lys-pNA substrate). The reactions were very fast and the active site of the inhibitors to plasmin was thought to be different from that to trypsin or chymotrypsin.


1981 ◽  
Vol 197 (3) ◽  
pp. 629-636 ◽  
Author(s):  
J L McKenzie ◽  
A K Allen ◽  
J W Fabre

Human and canine brain Thy-1 antigens were solubilized in deoxycholate and antigen activity was followed both by conventional absorbed anti-brain xenosera of proven specificity and by mouse monoclonal antibodies to canine and human Thy-1. It is shown that greater than 80% of Thy-1 activity in the dog and man binds to lentil lectin, that the mobility on sodium dodecyl sulphate/polyacrylamide-gel electrophoresis of canine and human Thy-1 is identical with that of rat Thy-1 and that the Stokes radius in deoxycholate of canine and human brain Thy-1 is 3.0 nm and 3.25 nm respectively. Both lentil lectin affinity chromatography followed by gel-filtration chromatography on the one hand and monoclonal antibody affinity chromatography on the other gave high degrees of purification of the brain Thy-1 molecule in the dog and man, resulting in single bands staining for both protein and carbohydrate on sodium dodecyl sulphate/polyacrylamide-gel electrophoresis (except for a slight contaminant of higher molecular weight staining for protein but not carbohydrate with human Thy-1 purified by lentil lectin and gel-filtration chromatography). Analysis of canine and human brain Thy-1 purified by monoclonal antibody affinity chromatography with additional gel filtration through Sephadex G-200 showed that these molecules had respectively 38% and 36% carbohydrate. The amino acid and carbohydrate compositions were similar to those previously reported for Thy-1 of the rat and mouse, the main point of interest being the presence in canine and human brain Thy-1 of N-acetylgalactosamine, which has been reported in rat and mouse brain Thy-1 but not in Thy-1 from other tissues.


1977 ◽  
Vol 23 (3) ◽  
pp. 240-252 ◽  
Author(s):  
J. Boisvert ◽  
T. Yamamoto

Vaccinia virus particles were dissociated into their constituent polypeptides and analysed by sodium dodecyl sulfate (SDS) gel electrophoresis. Thirty-three distinct polypeptide bands were identified and their molecular weights ranged between 11 000 and 150 000 daltons.Specific staining of gels containing polypeptides of dissociated virions revealed the presence of eight glycopeptides. No lipopeptides were detected.Analysis of chemical extracts (urea, guanidine hydrochloride, and alkali treatment) of the virus by SDS gel electrophoresis indicated that a total of 10 to 14 different polypeptides ranging in molecular weights from 11 000 to 70 000 daltons were solubilized.Analysis of detergent extracts and of the remains of extracted viral particles has shown that the detergent Nonidet P-40 (NP-40) solubilized a total of 11 polypeptides of which 6 were glycopeptides. The other detergents sodium deoxycholate (SDC) and cetyl trimethyl ammonium bromide (CTAB) were not as selective, both solubilizing more than 25 of the polypeptides composing the virus. Gel electrophoresis results also indicated that most of the small molecular weight (11 000–70 000 daltons) polypeptides were readily solubilized by NP-40, SDC, and CTAB, while those with molecular weights of 70 000 daltons and higher were not well solubilized.The effects of detergents were also analysed by electron microscopy. Evidence was obtained for subpopulations of viral particles having different susceptibility to detergent extraction.


2000 ◽  
Vol 66 (1) ◽  
pp. 252-256 ◽  
Author(s):  
Katsuichi Saito ◽  
Kazuya Kondo ◽  
Ichiro Kojima ◽  
Atsushi Yokota ◽  
Fusao Tomita

ABSTRACT Streptomyces exfoliatus F3-2 produced an extracellular enzyme that converted levan, a β-2,6-linked fructan, into levanbiose. The enzyme was purified 50-fold from culture supernatant to give a single band on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The molecular weights of this enzyme were 54,000 by SDS-PAGE and 60,000 by gel filtration, suggesting the monomeric structure of the enzyme. The isoelectric point of the enzyme was determined to be 4.7. The optimal pH and temperature of the enzyme for levan degradation were pH 5.5 and 60°C, respectively. The enzyme was stable in the pH range 3.5 to 8.0 and also up to 50°C. The enzyme gave levanbiose as a major degradation product from levan in an exo-acting manner. It was also found that this enzyme catalyzed hydrolysis of such fructooligosaccharides as 1-kestose, nystose, and 1-fructosylnystose by liberating fructose. Thus, this enzyme appeared to hydrolyze not only β-2,6-linkage of levan, but also β-2,1-linkage of fructooligosaccharides. From these data, the enzyme from S. exfoliatus F3-2 was identified as a novel 2,6-β-d-fructan 6-levanbiohydrolase (EC 3.2.1.64 ).


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