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Carboxypeptidase porcine

When purified in this way, porcine carboxypeptidase B is electrophoret-ically homogeneous in a 0.05 M phosphate buffer, pH 7.02. Sedimentation-... [Pg.175]

Amino Acid Composition of Bovine Carboxypeptidase A and Porcine Carhoxypeplidase B... [Pg.176]

Carboxypeptidase A Carboxypeptidase B Carboxypeptidase C Amino peptidase M Leucine amino peptidase Porcine kidney Endopeptidases... [Pg.427]

Further commercial interest was found by the transpeptidation reaction of porcine insulin to human insulin, the latter only differing in the last amino acid of Ae B-chain (Ala-B30 to Thr-B30). This reaction proceeds under kinetic control with trypsin, carboxypeptidase Y or achromobacter lyticus protease I. ... [Pg.399]

Fig. 2. Three-dimensional structural representations for zinc metall-oproteins. Comparison of the zinc ion-protein bonding interactions for zinc requiring enzymes (A—C) with the zinc-insulin hexamer (D, E). (A) Human carbonic anhydrase C, redrawn from Ref. (47) with permission. (B) Bovine carboxypeptidase Ay, redrawn from Ref. 30) with permission. (C) Bacillus thermoprotedyticus thermolysin, redrawn from Ref. 45) with permission. (D) and (E) Porcine Zn-insulin hexamer, taken from Ref. 48) with permission. The composite electron density maps in (D) and (E) show that each of the two zinc atoms present in the hexamer is within inner sphere bonding distance of three solvent molecules and three histidyl imidazolyl groups in an octahedral array about the metal ion. The position of one of the three equivalently positioned solvent molecules is indicated in (D). The electron density map in (E) shows the relative orientations of the three histidyl residues (His-BlO). (The atomic positions of one of the three equivalent histidyl groups are shown)... Fig. 2. Three-dimensional structural representations for zinc metall-oproteins. Comparison of the zinc ion-protein bonding interactions for zinc requiring enzymes (A—C) with the zinc-insulin hexamer (D, E). (A) Human carbonic anhydrase C, redrawn from Ref. (47) with permission. (B) Bovine carboxypeptidase Ay, redrawn from Ref. 30) with permission. (C) Bacillus thermoprotedyticus thermolysin, redrawn from Ref. 45) with permission. (D) and (E) Porcine Zn-insulin hexamer, taken from Ref. 48) with permission. The composite electron density maps in (D) and (E) show that each of the two zinc atoms present in the hexamer is within inner sphere bonding distance of three solvent molecules and three histidyl imidazolyl groups in an octahedral array about the metal ion. The position of one of the three equivalently positioned solvent molecules is indicated in (D). The electron density map in (E) shows the relative orientations of the three histidyl residues (His-BlO). (The atomic positions of one of the three equivalent histidyl groups are shown)...
Transpeptidation reactions with proteolytic enzymes have been frequently observed, too the first example of Fraenkel-Conrat mentioned at the beginning of this section belongs to this type of reactions. A remarkable instance for a transpeptidation reaction is the transformation of pork insulin into human insulin by carboxypeptidase A [35]. This enzyme splits a carboxyl-terminal amino acid from the end of a polypeptide chain and also catalyzes the transpeptidation at the same linkage. Thus, in the B-chain of porcine insulin the terminal alanin is exchanged by threonine on incubation with the enzyme and a large excess of this amino acid. [Pg.60]

A more general use of proteolytic enzymes in peptide synthesis became feasible with the discovery (Sealock and Laskowsky 1969) of the effect of water miscible organic solvents on the equilibrium in enzyme catalyzed peptide bond hydrolysis and synthesis. In the presence of isopropanol (or dimethylfor-mamide, etc.) the dissociation of the carboxyl group is suppressed and, at least in a selected pH region, the equilibrium is shifted toward synthesis. A notable case is the conversion of porcine insulin to human insulin. Enzymatic cleavage of the C-terminal residue of the B-chain (alanine) with carboxypeptidase yields desalanino pork insulin. This cleavage is followed by the incorporation of... [Pg.68]

Dipeptidyl Carboxypeptidases.—Dipeptidyl carboxypeptidase (angiotensin I-converting enzyme) has been purified by conventional techniques from a particulate fraction of porcine kidney cortex. The purified enzyme gave two protein bands on standard disc-gel electrophoresis, but showed a single protein component after treatment with neuraminidase. It was concluded that the preparation was a mixture of sialo- and asialo-enzymes and that neuraminic acid residues did not contribute to the catalytic activity. [Pg.472]

The storage of porcine muscle homogenate at various pHs and 4 C for 5 days also shows that the increase in free amino acids is very small in an acidic pH region, while it is large under neutral pH (Figure 2). Since carboxypeptidase activities have been reported to be very slight in the muscle (55), the increase in free amino acids appears to be caused by the action of aminopeptidases which possess the optimal pH in the neutral region. [Pg.425]


See other pages where Carboxypeptidase porcine is mentioned: [Pg.357]    [Pg.446]    [Pg.94]    [Pg.170]    [Pg.139]    [Pg.171]    [Pg.175]    [Pg.176]    [Pg.176]    [Pg.307]    [Pg.1352]    [Pg.1036]    [Pg.180]    [Pg.452]    [Pg.342]    [Pg.161]    [Pg.26]    [Pg.92]   
See also in sourсe #XX -- [ Pg.175 ]




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