CHARACTERIZATION OF RECOMBINANT HUMAN SINGLE-CHAIN LOW MOLECULAR WEIGHT UROKINASE (RE-SC-LUK)

1987 ◽  
Author(s):  
W A Günzler ◽  
B Wolf ◽  
L Flohé

RE-SC-LUK obtained from recomoinant b. con Bacteria showed a molecular mass similar to that of recombinant two-chain LUK (RE-TC-LUK) as judged from SDS-PAGE. By “Western“ blot analysis immunoreactivity of RE-SC-LUK was observed with monoclonal antibodies directed against the B chain but not with those against the A1 chain of urokinase. N-terminal sequence analysis c RE-SC-LUK showed identity to the A, chain of RE-TC_LUK and provided evidence for its single-chain nature, i.e. integrity of the Lys-Ile bond which is split in TC-UK. In all other respects structural identity of RE-SC-LUK and RE-TC-LUK was demonstrated by fingerprinting of fragments. Similar to recombinant pro-urokinase (RE-SCU-PA), RE-SC-LUK exhibits only marginal amidolytic activity, which is greatly enhanced by treatment with plasmin, but considerable fibrinolytic activity in a fibrin agar plate test.Thus, RE-SC-LUK is characterized as a fragment (residues 136 -411) of RE-SCU-PA, which lacks the “growth factor” and “kringle” domains. Moreover further evidence is provided that a free N-terminus of the B chain is essential for amidolytic but not for fibrinolytic activity of urokinase in more complex systems.

1987 ◽  
Author(s):  
F Tokunaga ◽  
T Miyata ◽  
T Nakamura ◽  
T Morita ◽  
S Iwanaga

Limulus clotting factor, factor C, is a lipopolysaccharide (LPS)-sensitive serine-protease zymogen present in the hemocytes. It is a two-chain glycoprotein (M.W. = 123,000) composed of a heavy chain (M.W. = 80,000) and a light chain (M.W. = 43,000) T. Nakamura et al. (1986) Eur. J. Biochem. 154, 511-521 .On further studies of this zymogen, a single-chain factor C (M.W. = 123,000) was identified by Western blotting technique. The heavy chain had an NH2-terminal sequence of Ser-Gly-Val-Asp-, which was consistent with the NH2-terminal sequence of the single-chain factor C, indicating that the heavy chain is located in the NH2-terminal part of the zymogen. The light chain had an NH22-terminal sequence of Ser-Ser-Gln-Pro-. Incubation of the two-chain zymogen with LPS resulted in the cleavage of a Phe-Ile bond between residues 72 and 73 of the light chain. Concomitant with this cleavage, the A (72.amino acids) and B chains derived from the light chain was formed. The complete amino acid sequence of the A chain was determined by automated Edman degradation. The A chain contained a typical segment which is similar structuraly to those a family of repeats in human β2 -glycoprotein I, complement factors B, Clr, Cls, H, C4b-binding protein, 02, coagulation factor XIII b subunit, haptoglobin a chain, and interleukin 2 receptor. The NH2-terminal sequence of the B chain was Ile-Trp-Asn-Gly-. This chain contained the serine-active site sequence of -ASP-Ala-Cys-Ser-Gly-Asp-SER-Gly-Gly-Pro-.These results indicate that limulus factor C exists in the hemocytes in a single-chain zymogen form and is converted to an active serine-protease by hydrolysis of a specific Phe-Ile peptide bond. The correlation of limulus factor C and mammalian complement proteins was also suggested.


1987 ◽  
Author(s):  
L Piérard ◽  
P Jacobs ◽  
D Gheysen ◽  
M Hoylaerts ◽  
A Cravador ◽  
...  

In order to produce plasminogen activators (PA) more specific and more active than their natural counterparts, we designed recombinant genes encoding mutant forms of urokinase (u-PA) and chimaeric molecules combining fragments of tissue type plasminogen activator (t-PA) and of u-PA. The following constructs have been realized : 1°) u-PA where amino acids Arg156 and Lys158 have been replaced by Thr. The purpose of this approach was to obtain a prourokinase molecule displaying similar properties as the natural single chain urokinase (scu-PA) but resistant to the cleavage by plasmin ; 2°) u-PA where the second cleavage site, Lys135-Lys136, was also eliminated either by replacing amino acid 132 to amino acid 147 by a shorter link (Ser-Thr) as found in t-PA, or by replacing the two lysines by glutamine residues. The resulting molecules correspond thus to completely uncleavable scu-PA forms ; 3°) an hybrid composed of the finger domain of t-PA and of the B-chain of u-PA ; 4°) an hybrid made of the A-chain of t-PA and of the B-chain of u-PA ; 5°) an hybrid where the kringle 2 of t-PA has been inserted between the kringle domain and the B-chain of u-PA. The last three constructs have been made to confer the fibrin binding specificity of t-PA to the B-chain of u-PA.All recombinant DNAs were introduced, via an expression vector, into R1610 and CosI cells. Secretion of the recombinant products was monitored by ELISA and activities were assayed in an immobilized system involving a monoclonal antibody (AAU2) raised against 33K u-PA, plasminogen and the specific chromogenic substrate S2251. In this assay, all recombinant products, except the plasmin resistant (156-158) scu-PA, showed apparent specific activities comparable to the activity of natural two-chain u-PA. Potential interest of these new plasminogen activators in therapy will be discussed and further characterization of the new molecules will-be presented.


1997 ◽  
Vol 52 (11-12) ◽  
pp. 740-746 ◽  
Author(s):  
Röbbe Wünschiers ◽  
Thomas Zinn ◽  
Dietmar Linder ◽  
Rüdiger Schulz

Abstract Purification of a soluble cytochrome c6 from the unicellular green alga Scenedesmus obliquus by a simple and rapid method is described. The purification procedure includes ammonium sulfate precipitation and non-denaturating PAGE. The N-terminal sequence of the first 20 amino acids was determined and shows 85% similarity and 75% identity to the sequence of cytochrome c6 from the green alga Monoraphidium braunii. The ferrocyto-chrome shows typical UV/VIS absorption peaks at 552.9, 521.9 and 415.7 nm. The apparent molecular mass was estimated to be 12 kD a by SDS-PAGE. EPR-spectroscopy at 20K shows resonances indicative for two distinct low-spin heme forms.


2010 ◽  
Vol 2010 ◽  
pp. 1-7 ◽  
Author(s):  
Rinky Rajput ◽  
Richa Sharma ◽  
Rani Gupta

An extracellular keratinase from Bacillus pumilus KS12 was purified by DEAE ion exchange chromatography. It was a 45 kDa monomer as determined by SDS PAGE analysis. It was found to be an alkaline, serine protease with pH and temperature optima of 10 and 60C, respectively. It was thiol activated with two- and eight-fold enhancement in presence of 10 mM DTT and β-mercaptoethanol, respectively. In addition, its activity was stimulated in the presence of various surfactants, detergents, and oxidizing agents where a nearly 2- to 3-fold enhancement was observed in presence of H2O2 and NaHClO3. It hydrolyzed broad range of complex substrates including feather keratin, haemoglobin, fibrin, casein,and α-keratin. Analysis of amidolytic activity revealed that it efficiently cleaved phenylalanine → leucine → alanine- p-nitroanilides. It also cleaved insulin B chain between Val2- Asn3, Leu6-Cys7 and His10-Leu11 residues.


1998 ◽  
Vol 331 (2) ◽  
pp. 513-519 ◽  
Author(s):  
Alberto VITALI ◽  
Bruno BOTTA ◽  
Giuliano DELLE MONACHE ◽  
Sabrina ZAPPITELLI ◽  
Paola RICCIARDI ◽  
...  

An acidic peroxidase (EC 1.11.1.7) produced by cell suspension cultures of Cassia didymobotrya(wild senna) was purified from culture medium collected on the 29th day. The enzyme was shown to be a glycoprotein with a pI of 3.5, a molecular mass of approx. 43 kDa by SDS/PAGE and 50 kDa by gel filtration. The N-terminal sequence was very similar to those of other plant peroxidases. The peroxidase was characterized by a high specificity towards coniferyl alcohol and other natural phenolics such as guaiacol and ferulic and caffeic acids. These findings suggest that the enzyme is involved in lignification processes of the cell wall. Moreover, the enzyme was able to catalyse the oxidation of 4,3´,4´-trihydroxychalcone and 4,3´,4´-trihydroxy-3-methoxychalcone to the corresponding 3,3´-biflavanones, as mixtures of racemic and mesoforms.


1990 ◽  
Vol 269 (1) ◽  
pp. 265-268 ◽  
Author(s):  
P Nyirkos ◽  
E E Golds

By SDS/PAGE analysis we have observed that human synovial cell monolayers secrete a prominent 39 kDa protein which could not be detected in skin and lung fibroblasts. This protein was purified to homogeneity by heparin-Sepharose chromatography and reverse-phase h.p.l.c. The N-terminal sequence was found to be almost identical to that of a recently described bovine protein detected in the mammary secretions during the involutionary phase of the lactational cycle. Characterization of this 39 kDa protein may provide a useful marker for classification of connective tissue cells.


1999 ◽  
Vol 338 (1) ◽  
pp. 139-145 ◽  
Author(s):  
Rami I. SABA ◽  
Alex BOLLEN ◽  
André HERCHUELZ

The Na/Ca exchanger is associated with 160, 120 and 70 kDa polypeptides whose nature is poorly understood. We have purified and characterized the Na/Ca exchanger from bovine cardiac sarcolemmal vesicles (SLVs) by using ion-exchange and affinity chromatographies. The Na/Ca exchanger-enriched fraction was reconstituted into asolectin liposomes [lipid to protein ratio 10:1 (w/w)] that showed Na/Ca exchange activity. Under non-reducing conditions, SDS/PAGE showed a single 70 kDa polypeptide, which was further characterized by immunoblots with different antibodies: SWant, raised against the purified exchanger protein; NH2-terminus, residues 1–21; NCX1, residues 393–406; and Exon F, residues 622–644. Immunoblots under reducing conditions with SWant, NH2-terminus and NCX1 showed three bands migrating at 160, 120 and 70 kDa for SLV preparations, whereas Exon F reacted only with the 160 and 120 kDa bands. Under non-reducing conditions, immunoblots with purified reconstituted Na/Ca exchanger showed a single band at 70 kDa reacting with SWant, NH2-terminus and NCX1 but not with Exon F. We conclude that the 70 kDa protein is associated with Na/Ca exchange activity, has the same N-terminal sequence as the cloned bovine cardiac exchanger, and has its length decreased by at least 35% from its C-terminal portion as compared with that of the wild-type exchanger.


1994 ◽  
Vol 81 (6) ◽  
pp. 910-913 ◽  
Author(s):  
Sadahiro Nomura ◽  
Shiro Kashiwagi ◽  
Hirosuke Fujisawa ◽  
Haruhide Ito ◽  
Kazuyuki Nakamura

✓ Fibrinogen, fibrin monomer, and D dimer were analyzed in 41 cases of chronic subdural hematoma (SDH) to characterize local rebleeding, coagulation, and fibrinolysis using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and immunoblotting. Chronic SDH's were divided into five groups according to their appearance on computerized tomography: high-density, isodensity, low-density, mixed-density, and layering types. The concentration of fibrinogen, which indicates rebleeding, was higher in the mixed-density (15.7 ± 3.4 mg/dl (mean ± standard error of the mean)) and layering (15.7 ± 2.6 mg/dl) types of hematoma, and lower in the low-density hematomas (1.4 ± 0.6 mg/dl) compared with the isodense hematomas (6.9 ± 1.1 mg/dl). Fibrin monomer, which indicates coagulative activity, had a distribution similar to that of fibrinogen: 87 ± 22, 18 ± 8, 175 ± 40, and 177 ± 23 µg/ml in isodense, low and mixed-density, and layering types of hematomas, respectively. The D dimer, which indicates fibrinolytic activity, was higher in the layering hematoma type (2032 ± 384 µg/ml), and lower in low-density hematomas (301 ± 164 µg/ml) compared to isodense (1310 ± 256 µg/ml) and mixed-density (1039 ± 207 µg/ml) types of hematomas. These observations suggest the following characterization of each type of chronic SDH. The layering type is active, with a high tendency to rebleed and for hyperfibrinolytic activity. The mixed-density type has a high tendency to rebleed with lower hyperfibrinolytic activity than the layering type. The low-density hematoma is stable with a low tendency to rebleed and to fibrinolytic activity.


1994 ◽  
Vol 303 (1) ◽  
pp. 171-176 ◽  
Author(s):  
C C Chu ◽  
S T Chu ◽  
S W Chen ◽  
Y H Chen

Three isotoxins (SP I-III) of the beta-bungarotoxin family were purified to homogeneity via a series of isolation procedures including a final step of h.p.l.c. on an SP column washed with a linear gradient of 0.2-0.6 M sodium acetate at pH 7.4. Their proportions varied greatly with the batch of venom. Each isotoxin was demonstrated by SDS/PAGE to contain a phospholipase A2 subunit and a non-phospholipase A2 subunit. The three proteins were reductively alkylated with 4-vinylpyridine and the alkylated derivatives of the two subunits of each isotoxin were separated. N-Terminal sequence analysis of the alkylated derivatives revealed that the three isotoxins probably share a common phospholipase A2 subunit but differ in their non-phospholipase A2 subunits. The non-phospholipase A2 subunits of SP II and SP III were identical with those of beta 2- and beta 1-toxin respectively, except that there was an additional valine inserted between Thr-18 and Val-19 in beta 2-toxin and Pro-18 and Val-19 in beta 1-toxin. The non-phospholipase A2 subunit of SP I differed greatly from that of SP III but was almost identical with that of SP II, except that Lys-14 and Ala-29 in SP II were replaced by Arg-14 and Glu-29 in SP I. Analysis of the effect of CaCl2 on protein fluorescence showed the existence of a low- and a high-affinity site on the different domains of each isotoxin for Ca2+ binding. The three isotoxins showed no great difference in their ability to bind Ca2+ on both the high- and low-affinity site. They had slightly different phospholipase A2 activities but differed to a great extent with respect to their neurotoxic effects. LD50 values increased in the order SP I > SP II > SP III. In contrast, the ability to inhibit the indirectly evoked contraction of chick biventer cervicis muscle was in the order SP III > SP II > SP I.


Insulin is a polypeptide hormone secreted by the β-cell of Islet’s of langerhan’s of the pancreas and cosists of two polypeptide chain-A and chain- B. It is linked by two inter chain disulphide bonds (A7- B7 and A20-B19) and also has an intra-chain disulphide bond in the A-Chain (A6-A11). For production of Insulin from goat pancreas saccharomyces cerevisae using as a vector. In this study Recombinant DNA technology, chromatography, Elecrophoresis, Spectrophotometer, SDS-PAGE, zymography etc techaniques were used. Humulin was tanken as a marker. It was found, goat insulin showed good result. 5.8 – 6.5 KDa recombinant insulin was calculated. It did not show antigenic proterties.


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