Bovine trypsinogen

Fehlhammer, H., Bode, W., Huber, R. Crystal structure of bovine trypsinogen at 1.8 A resolution. 11. Crystallographic refinement, refined crystal structure and comparison with bovine trypsin. J. Mol. Biol. 

Kenner, R. A. and Aboderin, A. A. (1971). A new fluorescent probe for protein and nucleoprotein conformation. Binding of 7-(p-Methoxyben-zylamino) -4-nitrobenzoxadiazole to bovine trypsinogen and bacterial ribosomes. Biochemistry 10, 4433 1440. 

Proteolytic activities were assayed in 50 mM sodium acetate, pH 2.7, 1% casein or hemoglobin at 30°C. The activation of bovine trypsinogen was done with 5 mM trypsinogen in 50 mM sodium citrate, pH 3.0 at 30°C. Parentheses indicate the percentages of the activities of wild-type aspergillopepsin I. 

In conclusion, the double mutant pepsin T77D/G78(S)S79 was also able to activate bovine trypsinogen to trypsin by the selective cleavage of the Lys6-Ile7 bond of trypsinogen. Results of this study suggest that the structure of the active site flap contribute to the Si substrate specificity for basic amino acid residues in aspartic proteinases. 

FIGURE 13 Plot of the logarithm of the retention volume (In VR) versus the concentration of the displacing salt, ammonium sulphate, in the HP-HIC mode with the proteins I, insulin B-chain 2, bovine trypsin inhibitor 3, bovine trypsinogen 4, insulin A-chain 5, ribonuclease 6, sperm whale myoglobin 7, horse heart cytochrome c. Data from Ref. 42. 

Cytochrome c, lysozyme, myoglobin, ribonuclease A Cytochrome c mixture (horse, tuna, chicken, and bovine) Cytochrome c mixture (horse, tuna, chicken, and bovine) Trypsinogen, a-chymotrypsinogen, ribonuclease A, cytochrome c... 

Bovine trypsinogen and trypsin are still prepared by the tedious and time-consuming technique of Northrop and Kunitz involving ammonium sulfate fractionations and crystallizations at alkaline pH. Trypsinogen can be crystallized only once and is obtained in rather impure state. Crystalline trypsin also is not pure. Besides NH2-terminal isoleucine, it contains some other end groups which are eliminated by further crystallizations of the DFP-inhibited derivative. 

Amino acid Bovine trypsinogen Porcine trypsinogen (126) ... 

Numbers of residues are given per 23,800 gm for bovine trypsinogen. They are given per 24,900 gm for porcine trypsinogen and also per 100 gm, since the molecular weight of this protein calculated from chemical analysis alone is still preliminary. Preliminary value estimated from chemical analysis. 

Bode, W. The transition of bovine trypsinogen to a trypsin-like state upon strong ligand binding. J. Molec. Biol. 127, 357-402 (1979). 

Bode, W, P. Schwager, R. Huber, The transition of bovine trypsinogen to a trypsin-like state upon strong ligand binding. The refined crystal structures of the bovine trypsinogen— pancreatic trypsin inhibitor complex and of its ternary complex with Ile-Val at 1.9 A resolution. J Mol Biol 1978, 118, 99-112. 

Bode, W, R. Huber, Induction of the bovine trypsinogen-trypsin transition by peptides sequentially similar to the N-terminus of trypsin. FEBS Lett 1976, 68, 231-236. 

Bovine trypsinogen and chymotrypsinogen. These two digestive enzyme precursors have single chains of 229 and 245 residues, respectively. 

Comparison of the structures of bovine trypsinogen and chymotrypsinogen A. Solid arrows show the hydrolysis sites that result in the activation of trypsinogen to trypsin, and chymotrypsinogen to chymotrypsin. Broken arrows are additional hydrolysis sites, leading to formation of a-chymotrypsin. Shaded circles represent amino acids that are Identical or similar in the two proteins. Disulfide bridges are lettered A to G. H represents the histidine residues, and S the serine residue of the active site this serine residue reacts with diisopropylfluorophosphate. Deletions are shown by lines between the circles. To aid comparison, the residue numbers of both structures are based on those of chymotrypsinogen. [B.S.Hartley etal. Nature 207 (1965) 1157-1159]... 

Fig. 7. Summary of P-NMR titration data of diisopropylphosphoryl derivatives of serine proteinases. The arrows represent the extent of titration shuts and the numbers indicate pA , values. Abbreviations DIP, diisopropylphosphoryl BCtg, bovine chymotrypsinogen A BTg, bovine trypsinogen PTg, porcine trypsinogen BCtr , bovine chymotrypsin A BTr, bovine trypsin PTr, porcine trypsin a-LP, a-lytic proteinase. From Porcubcu et al. (1979). Copyright 1979 American Chemical Society.

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