Proteolytic enzymes have many physiological functions, ranging from generalized protein digestion to more specific regulated processes such as the activation of zymogens, blood coagulation and the lysis of fibrin clots, the release of hormones and pharmacologically active peptides from precursor proteins, and the transport of secretory proteins across membranes. They are present in all forms of living organisms. Comparisons of amino acid sequences, three-dimensional structures, and enzymatic reaction mechanisms of proteases indicate that there are distinct families of these proteins. Changes in molecular structure and function have accompanied the evolution of proteolytic enzymes and their inhibitors, each having relatively simple roles in primitive organisms and more diverse and more complex functions in higher organisms.

http://science.sciencemag.org/content/sci/224/4647/350.full.pdf

Evolution of proteolytic enzymes

The complete amino acid sequence of amphiregulin, a bifunctional cell growth modulator, was determined. The truncated form contains 78 amino acids, whereas a larger form of amphiregulin contains six additional amino acids at the amino-terminal end. The amino-terminal half of amphiregulin is extremely hydrophilic and contains unusually high numbers of lysine, arginine, and asparagine residues. The carboxyl-terminal half of amphiregulin (residues 46 to 84) exhibits striking homology to the epidermal growth factor (EGF) family of proteins. Amphiregulin binds to the EGF receptor but not as well as EGF does. Amphiregulin fully supplants the requirement for EGF or transforming growth factor-alpha in murine keratinocyte growth, but it is a much weaker growth stimulator in other cell systems.

https://science.sciencemag.org/content/sci/243/4894/1074.full.pdf

Structure and function of human amphiregulin: a member of the epidermal growth factor family

The role of phospholipid and factor VIIIa in the activation of bovine factor X.

Evolution of the proteases of blood coagulation and fibrinolysis by assembly from modules

Factor VII is a precursor to a serine protease that is present in mammalian plasma. In its activated form, it participates in blood coagulation by activating factor X and/or factor IX in the presence of tissue factor and calcium. Clones coding for factor VII were obtained from two cDNA libraries prepared from poly(A) RNA from human liver and Hep G2 cells. The amino acid sequence deduced from the cDNAs indicates that factor VII is synthesized with a prepro-leader sequence of 60 or 38 amino acids. The mature protein that circulates in plasma is a single-chain polypeptide composed of 406 amino acids. The amino acid sequence analysis of the protein and the amino acid sequence deduced from the cDNAs indicate that factor VII is converted to factor VIIa by the cleavage of a single internal bond between arginine and isoleucine. This results in the formation of a light chain (152 amino acids) and a heavy chain (254 amino acids) that are held together by a disulfide bond. The light chain contains a gamma-carboxyglutamic acid (Gla) domain and two potential epidermal growth factor domains, while the heavy chain contains the serine protease portion of the molecule. Factor VII shows a high degree of amino acid sequence homology with the other vitamin K-dependent plasma proteins.

https://www.pnas.org/content/pnas/83/8/2412.full.pdf

Characterization of a cDNA coding for human factor VII

The amino acid sequence of bovine blood coagulation Factor IX (Christmas Factor) is presented and compared with the sequences of other vitamin K-dependent plasma proteins and pancreatic trypsinogen. The 416-residue sequence of Factor IX was determined largely by automated Edman degradation of two large segments, containing 181 and 235 residues, isolated after activating Factor IX with a protease from Russell's viper venom. Subfragments of the two segments were produced by enzymatic digestion and by chemical cleavage of methionyl, tryptophyl, and asparaginyl-glycyl bonds. Comparison of the amino acid sequences of Factor IX, Factor X, and Protein C demonstrates that they are homologous throughout. Their homology with prothrombin, however, is restricted to the amino-terminal region, which is rich in gamma-carboxyglutamic acid, and the carboxyl-terminal region, which represents the catalytic domain of these proteins and corresponds to that of pancreatic serine proteases.

Comparison of amino acid sequence of bovine coagulation Factor IX (Christmas Factor) with that of other vitamin K-dependent plasma proteins.

https://febs.onlinelibrary.wiley.com/doi/pdf/10.1016/0014-5793%2878%2980073-8

Cleavage of γ-carboxyglutamyl peptide bonds by cyanogen bromide and by N-bromosuccinimide

https://febs.onlinelibrary.wiley.com/doi/pdf/10.1016/0014-5793%2877%2980193-2

Kouichi Katayama

Papers

Comparison of amino acid sequence of bovine coagulation Factor IX (Christmas Factor) with that of other vitamin K-dependent plasma proteins.

Cleavage of γ-carboxyglutamyl peptide bonds by cyanogen bromide and by N-bromosuccinimide

Radioimmunoassay of pig pancreatic elastase

Effective isolation method of human pancreatic elastase-1 by use of immunoadsorbent affinity chromatography.