scholarly journals The preparation of crystalline human l-lactate–nicotinamide–adenine dinucleotide oxidoreductase isoenzyme 1 involving preparative polyacrylamide-gel electrophoresis

1974 ◽  
Vol 143 (2) ◽  
pp. 453-460 ◽  
Author(s):  
Alan V. Emes ◽  
Michael J. Gallimore ◽  
Alan W. Hodson ◽  
Albert L. Latner
Keyword(s):  
Amino Acid ◽  
Active Site ◽  
Nicotinamide Adenine Dinucleotide ◽  
Gel Electrophoresis ◽  
Specific Activity ◽  
Polyacrylamide Gel Electrophoresis ◽  
Polyacrylamide Gel ◽  
Amino Acid Residues ◽  
Protein Contamination ◽  
Nad Oxidoreductase

A method is presented for the preparation of human heart lactate dehydrogenase (l-lactate–NAD+ oxidoreductase; EC 1.1.1.27) isoenzyme 1; this involves the use of polyacrylamide-gel electrophoresis as a preparative step. The yield was about 10% with a final specific activity of 220 units/mg of protein, one unit being defined as the amount of enzyme catalysing the oxidation of 1μmol of NADH/min at 25°C, in the presence of 0.33mm-pyruvate. The crystalline preparation contained less than 2% of the other isoenzymes, was homogeneous in the ultracentrifuge and showed only a trace of protein contamination on polyacrylamide-gel electrophoresis. Some properties of the crystalline isoenzyme are reported; E1%1cm=13.2 at 280nm, s020,w=7.43S, pI=4.6, and the apparent Km for pyruvate=1.02×10−4m. The human isoenzyme and the isoenzyme from pig heart differ with respect to amino acid composition, electrophoretic mobility and solubility. It is possible that these differences do not involve the active site, or sites, but are due to changes in amino acid residues elsewhere in the molecule. The importance of purified human LDH-1 isoenzyme with regard to enzyme radioimmunoassay is emphasized.

scholarly journals Structural properties of homogeneous protein disulphide-isomerase from bovine liver purified by a rapid high-yielding procedure

1983 ◽  
Vol 213 (1) ◽  
pp. 225-234 ◽  
Author(s):  
N Lambert ◽  
R B Freedman
Keyword(s):  
Amino Acid ◽  
Sodium Dodecyl Sulphate ◽  
Gel Electrophoresis ◽  
Specific Activity ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Sedimentation Coefficient ◽  
Bovine Liver ◽  
Polyacrylamide Gel ◽  
Protein Disulphide Isomerase

Protein disulphide-isomerase from bovine liver was purified to homogeneity as judged by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis, two-dimensional electrophoresis and N-terminal amino acid analysis. The preparative procedure, a modification of that of Carmichael, Morin & Dixon [(1977) J. Biol. Chem. 252, 7163-7167], is much faster and higher-yielding than previous procedures, and the final purified material is of higher specific activity. The enzyme has Mr 57 000 as determined by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis, both in the presence and in the absence of thiol compounds. Gel-filtration studies on Sephadex G-200 indicate an Mr of 107 000, suggesting that the native enzyme is a homodimer with no interchain disulphide bonds. Ultracentrifugation studies give a sedimentation coefficient of 3.5S, implying that the enzyme sediments as the monomer. The isoelectric point, in the presence of 8 M-urea, is 4.2, and some microheterogeneity is detectable. The amino acid composition is comparable with previous analyses of this enzyme from bovine liver and of other preparations of thiol:protein disulphide oxidoreductases whose relation to protein disulphide-isomerase has been controversial. The enzyme contains a very high proportion of Glx + Asx residues (27%). The N-terminal residue is His. The pure enzyme has a very small carbohydrate content, determined as 0.5-1.0% by the phenol/H2SO4 assay. Unless specific steps are taken to remove it, the purified enzyme contains a small amount (5 mol/mol of enzyme) of Triton X-100 carried through the purification.

Isolation of Two Bovine Amelogenin Peptides and Their Amino Acid Sequences

1987 ◽  
Vol 1 (2) ◽  
pp. 276-281 ◽  
Author(s):  
J.-H. Yeh ◽  
T. Takagi ◽  
S. Sasaki
Keyword(s):  
Molecular Weight ◽  
Amino Acid ◽  
Gel Electrophoresis ◽  
Polyacrylamide Gel Electrophoresis ◽  
Amino Acid Sequences ◽  
Polyacrylamide Gel ◽  
The Other ◽  
Edman Degradation ◽  
Amino Acid Residues ◽  
Peptide Fractions

Two peptide fractions of bovine amelogenin having a highly aggregative property to form polymers were purified by chromatography, SDS-polyacrylamide gel electrophoresis, and HPLC. Amino acid sequences of purified peptides were determined by automated Edman degradation. One peptide was found to be composed of 63 amino acid residues having a molecular weight of 7105, and the other of 86 residues having that of 9683. The sequence of the smaller peptide was identical to the C-terminal 63 residues of the amelogenin molecule of 170 residues previously reported, but the larger contained eight residues which are absent in the amelogenin sequence. There is a possibility that the latter peptide might be synthesized independently from mRNA spliced at different positions.

scholarly journals Purification and characterization of a phospholipase A2 from the venom of the coral snake, Micrurus fulvius microgalbineus (Brown and Smith)

1979 ◽  
Vol 179 (3) ◽  
pp. 603-606 ◽  
Author(s):  
L D Possani ◽  
A C Alagòn ◽  
P L Fletcher ◽  
M J Varela ◽  
J Z Juliá
Keyword(s):  
Amino Acid ◽  
Phospholipase A2 ◽  
Gel Electrophoresis ◽  
Specific Activity ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Polyacrylamide Gel ◽  
Coral Snake ◽  
Phospholipase Activity ◽  
Crude Venom

A phospholipase A2 was purified from the Mexican coral snake Micrurus fulvius microgalbieus (Brown and Smith). Gel filtration of the soluble crude venom on Sephadex g-50 resolved five fractions, of which fraction II had 98% of the total phospholipase activity. This fraction was rechromatographed on a CM-cellulose column that resolved eight fractions, four of which had an important phospholipase activity. The first fraction (II-1) was homogeneous by polyacrylamide-gel electrophoresis and displayed a phospholipase specific activity of 920 units/mg of protein. The apparent molecular weight as determined by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis was approx. 14000. The amino acid analysis revealed the presence of 119 amino acid residues, with 12 half-cystines. the N-terminal sequence was shown to be Ser-Leu-Leu-Asx-Phe-Lys-Asx-Met-Ile-Glu-Ser-Thr..., which is homologous with that of phospholipases from other snake venoms.

scholarly journals Human liver alkaline phosphatase purified by affinity chromatography, ultracentrifugation and polyacrylamide-gel electrophoresis

1976 ◽  
Vol 159 (3) ◽  
pp. 697-705 ◽  
Author(s):  
A L Latner ◽  
A W Hodson
Keyword(s):  
Alkaline Phosphatase ◽  
Amino Acid ◽  
Gel Electrophoresis ◽  
Amino Acid Analysis ◽  
Human Liver ◽  
Specific Activity ◽  
Polyacrylamide Gel Electrophoresis ◽  
Polyacrylamide Gel ◽  
Nitrophenyl Phosphate ◽  
Hydrolysis Of

A method is presented for the preparation of human liver alkaline phosphatase (orthophosphoric monoester phosphohydrolase, EC 3.1.3.1). The method gives a purification factor of 12.5 × 10(3) over the initial aq. butan-1-ol extract, a recovery of 6.0% and a specific activity for the preparation of 1450-1550 units/mg of protein, 1 unit being defined as the amount of enzyme catalysing the hydrolysis of 1mumol of p-nitrophenyl phosphate/min at 35 degrees C in 0.1 M-2-amino-2-methylpropan-1-ol/HCl buffer, pH 10.5, containing 10mM-p-nitrophenyl phosphate. Homogeneity was studied by ultracentrifugation, by immunoelectrophoresis and by polyacrylamide-gel electrophoresis. A single contaminating protein was present which was less than 5% of the total. Ultracentrifugation and equilibrium-gradient-pore electrophoresis techniques indicated a mol.wt. of 156000 and 160000 respectively. Equilibrium-gradient-pore electrophoresis indicated that the alkaline phosphatase molecule is possibly a dimer, comprising two subunits of about 80000 mol.wt. Amino acid analysis proved remarkably similar to that for alkaline phosphatase from other sources, regardless of species.

scholarly journals Purification, characterization and radioimmunoassay of adenosine deaminase from human leukaemic granulocytes

1981 ◽  
Vol 195 (2) ◽  
pp. 389-397 ◽  
Author(s):  
D A Wiginton ◽  
M S Coleman ◽  
J J Hutton
Keyword(s):  
Molecular Weight ◽  
Adenosine Deaminase ◽  
Gel Electrophoresis ◽  
Specific Activity ◽  
Periodic Acid ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Polyacrylamide Gel ◽  
Periodic Acid Schiff ◽  
Apparent Homogeneity

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.

scholarly journals Cleavage of bacterial flagellin with cyanogen bromide. Chemical and physical properties of the protein fragments

1969 ◽  
Vol 113 (3) ◽  
pp. 489-499 ◽  
Author(s):  
C. R. Parish ◽  
G. L. Ada
Keyword(s):  
Amino Acid ◽  
Gel Electrophoresis ◽  
Amino Acid Analysis ◽  
Cyanogen Bromide ◽  
Degradation Products ◽  
Polyacrylamide Gel Electrophoresis ◽  
Polyacrylamide Gel ◽  
Gel Chromatography ◽  
Molecular Weights ◽  
Lysine Residues

1. Flagellin, isolated from the flagella of Salmonella adelaide, was shown by various criteria to be a pure protein. It had a molecular weight of about 40000 and contained three methionine, six tyrosine, 11 arginine and 25 lysine residues/mol., of which 11 of the lysine residues were present as ∈-N-methyl-lysine. 2. After treatment of flagellin with cyanogen bromide in formic acid, four main fragments (A, B, C and D) were obtained, with as many as six minor components that represented partial degradation products. The major fragments were estimated by amino acid analysis to have molecular weights of about 18000 for fragment A, 12000 for fragment B, 5500 for fragment C and 4500 for fragment D. Fragments A, B and D, but not fragment C, were recovered pure by gel chromatography as monitored by polyacrylamide-gel electrophoresis. 3. A complex between fragments C and D was also isolated (mol.wt. 10000) after limited oxidation of flagellin by chloramine-t before digestion by cyanogen bromide. After oxidation essentially only two fragments were released from flagellin by cyanogen bromide: the ‘C,D’ complex and a presumed ‘AB’ fragment. 4. The sum of the amino acid analyses of fragments A and B and the ‘C,D’ complex gave residue values that agreed well with the amino acid composition of native flagellin. 5. Fragments A and D contained tyrosine, and ten of the 11 ∈-N-methyl-lysine residues of the molecule were in fragment A. Reaction with [125I]iodide at small extents of substitution showed that, in flagellin, the tyrosine residue of fragment D was more readily substituted than those of fragment A. By contrast, in polymerized flagellin, the tyrosine residues of fragment A were more readily substituted. 6. Treatment of flagellin with carboxypeptidases A and B revealed the C-terminal sequence -Leu-Leu-Leu-Arg. Arginine and leucine were released by carboxypeptidase from the ‘C,D’ complex but not from fragment D, indicating that fragment C was C-terminal. 7. On the basis of the results from amino acid analysis, carboxypeptidase digestion, N-terminal analysis, iodination studies and polyacrylamide-gel electrophoresis, the sequence of fragments in flagellin was considered to be B–A–D–C; in the polymer, fragment A was exposed. It is suggested that methylation of the lysine residues occurred in the organism after flagellin had polymerized.

scholarly journals Dermatan sulphate proteoglycans of human articular cartilage. The properties of dermatan sulphate proteoglycans I and II

1989 ◽  
Vol 262 (3) ◽  
pp. 823-827 ◽  
Author(s):  
P J Roughley ◽  
R J White
Keyword(s):  
Articular Cartilage ◽  
Gel Electrophoresis ◽  
Core Protein ◽  
Polyacrylamide Gel Electrophoresis ◽  
Polyacrylamide Gel ◽  
Human Articular Cartilage ◽  
Amino Acid Residues ◽  
Dermatan Sulphate ◽  
Sulphate Proteoglycan ◽  
Core Proteins

Dermatan sulphate proteoglycans were purified from juvenile human articular cartilage, with a yield of about 2 mg/g wet wt. of cartilage. Both dermatan sulphate proteoglycan I (DS-PGI) and dermatan sulphate proteoglycan II (DS-PGII) were identified and the former was present in greater abundance. The two proteoglycans could not be resolved by agarose/polyacrylamide-gel electrophoresis, but could be resolved by SDS/polyacrylamide-gel electrophoresis, which indicated average Mr values of 200,000 and 98,000 for DS-PGI and DS-PGII respectively. After digestion with chondroitin ABC lyase the Mr values of the core proteins were 44,000 for DS-PGI and 43,000 and 47,000 for DS-PGII, with the smaller core protein being predominant in DS-PGII. Sequence analysis of the N-terminal 20 amino acid residues reveals the presence of a single site for the potential substitution of dermatan sulphate at residue 4 of DS-PGII and two such sites at residues 5 and 10 for DS-PGI.

Characterization of the interaction between chymotrypsin and heparin

1977 ◽  
Vol 55 (2) ◽  
pp. 134-139 ◽  
Author(s):  
Sally S. Twining ◽  
Arthur S. Brecher
Keyword(s):  
Complex Formation ◽  
Active Site ◽  
Gel Electrophoresis ◽  
Polyacrylamide Gel Electrophoresis ◽  
Enzymic Activity ◽  
Polyacrylamide Gel ◽  
Activity Data

Heparin forms a complex with chymotrypsin which is active towards glutaryl-L-phenylalanine-p-nitroanilide (GPANA) and glutaryl-L-phenylalanine-β-naphthylamide (GPNA) at pH 7.6. The activity of chymotrypsin towards GPANA at pH 7.6 is enhanced in the presence of heparin. Heparin does not bind at the active site of the enzyme since proflavin is not displaced from the active site of chymotrypsin upon complex formation. The heparin–chymotrypsin complex migrates under basic polyacrylamide disc gel electrophoresis conditions to a position intermediate between heparin and free chymotrypsin. The complex is dissociable under acidic polyacrylamide gel electrophoresis conditions. It is estimated that one to three molecules of heparin can bind to each chymotrypsin molecule on the basis of electrophoretic and enzymic activity data.

scholarly journals Purification and biochemical characterization of three major acidic proteins (BSP-A1, BSP-A2 and BSP-A3) from bovine seminal plasma

1987 ◽  
Vol 241 (3) ◽  
pp. 685-692 ◽  
Author(s):  
P Manjunath ◽  
M R Sairam
Keyword(s):  
Amino Acid ◽  
Amino Acid Composition ◽  
Acid Composition ◽  
Seminal Plasma ◽  
Gel Electrophoresis ◽  
Polyacrylamide Gel Electrophoresis ◽  
Gel Filtration ◽  
Polyacrylamide Gel ◽  
Terminal Residue ◽  
Acidic Proteins

Three major acidic proteins of bovine seminal plasma, BSP-A1, BSP-A2 and BSP-A3, were purified to homogeneity, by employing fast protein liquid chromatography, gel filtration and h.p.l.c. The proteins were purified on the basis of their stimulatory effect on the basal release of gonadotropins by rat anterior-pituitary cells in culture. All three proteins migrated as distinct single bands in the presence or absence of 2-mercaptoethanol in SDS/polyacrylamide-gel electrophoresis. Their Mr values were estimated to be between 15,000 and 16,500 by SDS/polyacrylamide-gel electrophoresis. Similar Mr estimates were obtained when they were subjected to gel filtration on a calibrated column of Sephadex G-75 equilibrated in 0.05 M-acetic acid, pH 3.0. However, BSP-A1 and BSP-A2 were eluted as aggregated molecules (Mr 60,000-120,000) during gel filtration on Sephadex G-200 equilibrated in 0.05 M-NH4HCO3, pH 8.5, or phosphate buffer, pH 7.0, containing 0.15 M-NaCl. In the presence of 8 M-urea both BSP-A1 and BSP-A2 were eluted at positions corresponding to Mr values of 17,000-20,000. BSP-A1 and BSP-A2 had an identical amino acid composition, which differed largely from that of BSP-A3. All three proteins contained aspartic acid as the N-terminal residue, and cysteine was identified as the C-terminal residue. BSP-A1 and BSP-A2 are glycoproteins containing galactosamine, sialic acid and neutral sugars, but BSP-A3 did not contain any covalently attached sugars. Whereas BSP-A2 and BSP-A3 were eluted unadsorbed, BSP-A1 bound to wheat-germ lectin-Sepharose 6MB and could be eluted by the competing sugar N-acetyl-D-glucosamine. Treatment of BSP-A1 and BSP-A2 with trypsin resulted in complete loss of gonadotropin-release activity, but BSP-A3 retained full activity. Antibody raised against BSP-A1 did not cross-react with BSP-A3, or vice versa. All these properties indicated marked structural differences between BSP-A3 and BSP-A1 (or BSP-A2). On the basis of amino acid composition it was concluded that BSP-A1, BSP-A2 and BSP-A3 are the same as the gonadostatins [Esch, Ling, Bohlen, Ying & Guillemin (1983) Biochem. Biophys. Res. Commun. 113, 861-867].

scholarly journals Amelogenins. Purification and partial characterization of proteins from developing bovine dental enamel

1973 ◽  
Vol 131 (3) ◽  
pp. 471-484 ◽  
Author(s):  
F. Michael Eggert ◽  
Grania A. Allen ◽  
Ralph C. Burgess
Keyword(s):  
Amino Acid ◽  
Gel Electrophoresis ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Dental Enamel ◽  
Polyacrylamide Gel ◽  
Sedimentation Equilibrium ◽  
Amino Acid Compositions ◽  
Small Proteins ◽  
Equilibrium Ultracentrifugation

1. Procedures are described for the purification of amelogenin electrophoretic components and their analysis for homogeneity by polyacrylamide-gel electrophoresis at both acidic and alkaline pH values. 2. Most of these components belonged to two main groups, termed the J group and the C group after their major electrophoretic components. Sodium dodecyl sulphate-polyacrylamide-gel electrophoresis indicated that, within each group, proteins were of similar size, but the C-group proteins were larger than those of the J group. 3. By sedimentation-equilibrium ultracentrifugation and amino acid analysis, the four J-group components were found to be very small proteins (mol. wt. 5500–3000) and, except for one, similar in amino acid composition. The components of the C group were found to be proteins of moderate size (mol. wt. 16800–16100) with very similar amino acid compositions. A third minor amelogenin group of intermediate size was also found, but not further analysed. Details of the results of the ultracentrifuge studies are given in a supplementary paper that has been deposited as Supplementary Publication SUP 50014 at the National Lending Library for Science and Technology, Boston Spa, Yorks. LS23 7BQ, U.K., from whom copies can be obtained on the terms indicated in Biochem. J. (1973) 131, 5. 4. Two of the J-group components were similar to amelogenins isolated by other workers. 5. All amelogenins analysed were rich in proline, glutamic acid, histidine and methionine, and contained no half-cystine. Their amino acid compositions, combined with their molecular weights, serve to distinguish the amelogenins from both collagens and keratins.

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