A i-proteinase

Proteinase inactivation occurs by a stoichiometric reaction between proteinase and inhibitor that results in the formation of a covalent ester bond between the reactive site residue of the inhibitor (Arg in antithrombin) and the active site residue (Ser in the proteinase). The proteinases thrombin, factor Xa, factor IXa, and, less effectively, factor Vila and factor XIa are all inactivated by antithrombin (Figure 36-16). Other SERPINS can inactivate procoagulant proteinases, heparin cofactor II can inactivate thrombin, and O I-proteinase inhibitor can inactivate factor Xa. An altered a i -proteinase inhibitor (a i -proteinase inhibitor... 

Brinkworth, R.I., Brindley, P.J. and Harrop, SA. (1996) Structural analysis of the catalytic site of ACCP-1, a cysteine proteinase secreted by the hookworm... 

The first hurdle encountered during the development of alfalfa as a recombinant protein production system was the relative inefficiency of the available expression cassettes. A study in which a tomato proteinase inhibitor I transgene was expressed in tobacco and alfalfa under the control of the cauliflower mosaic virus (CaMV) 35S promoter showed that 3-4 times more protein accumulated in tobacco leaves compared to alfalfa leaves [5]. Despite the low efficiency of the CaMV 35S promoter in alfalfa, bio-pharmaceutical production using this system has been reported in the scientific literature. Such reports include expression of the foot and mouth disease virus antigen [6], an enzyme to improve phosphorus utilization [7] and the anti-human IgG C5-1 [8]. In this last work, the C5-1 antibody accumulated to 1% total soluble protein [8]. 

A serpin is a xerine proteinase inhibitor that forms cata-lytically inactive complexes which, after cleavage of the pi pif linkage, releases the inhibitor very slowly. O Malley et al. recently demonstrated that antichymo-trypsin (1) binds to chymotrypsin (E) to form an E I complex via a three-step mechanism ... 

Determination of acute-phase proteins (CRP, orosomucoid, haptoglobin, transferrin, prealbumin), immunoglobulins (IgA, IgG, IgM), compressive markers (albumin, fibrinogen), markers of tissue destruction (Apo A-I, A-II, Apo B), components of complement (C3, C4), proteinase inhibitors (antithrombin HI, a -antitrypsin). The measurement was performed simultaneously in CSF and in serum (plasma) by a laser nephelometric method. The functional state of the blood-CSF barrier was evaluated numerically with the help of the quotient Q = Albcsp/s and also by the intrathecal synthesis of immunoglobulins according to Reiber s formula and for each class—IgG, IgM, IgA. 

Nagano, I., Pei, F., Wu, Z., Wu, J., Cui, H., Boonmars, T. and Takahashi, Y. (2004) Molecular expression of a cysteine proteinase of Clonorchis sinensis and its application to an enzyme-linked immunosorbent assay for immunodiagnosis of clonorchiasis. Clinical, Diagnostic and Laboratory Immunology 11, 411 f16. 

Nagata, K., Kudo, N., Abe, K., Arai, S., and Tanokura, M. 2000. Three-dimensional solution structure of oryzacystatin-I, a cysteine proteinase inhibitor of the rice, Oryza sativa L. japonica. Biochemistry 39 14753-14760. 

Zapelena, M. J., Zalacain, I., Pena, P. D., Astiasaran, I., and Bello, J. 1997. Effect of the addition of a neutral proteinase from Bacillus subtilis (Neutrase) on nitrogen fractions and texture of Spanish fermented sausage. J. Agric. Food Chem., 45, 2798-2801. 

Hypochlorite, released from inflammatory cells, can induce the inactivation of a i-antiproteinase by oxidising a crucial methionine residue at the active centre of the enzyme. Inactivation of the a j-proteinase inhibitor may allow proteases... 

A8. Abrahamson, M., Ritonja, A., Brown, M. A., Grubb, A., Machleidt, W., and Barrett, A. I., Identification of the probable inhibitory reactive sites of the cysteine proteinase inhibitors human cystatin C and chicken cystatin. J. Biol. Chem. 262(20), 9688—9694 (1987). 

A third proteinase appears to exist in the gastric juice, which exerts proteolytic activity at a neutral pH of about 7.0, i.e., in the range where pepsin and cathepsin no longer are active. The existence of a protease called parachymosin, active at pH 5.0-7.0, has been described in the past (Fig. 1) (see B46). Buchs (JM6) considered it to be an integral part of the gastric protease, the two other components of which were pepsin and cathepsin. In the early thirties, Castle s group found some paral-... 

In adults, a severe form of lung injury can develop in association with sepsis, pneumonia, and injury to the lungs due to trauma or surgery. This catastrophic disorder is known as acute respiratory distress syndrome (ARDS) and has a mortality rate of more than 40%. In ARDS, one of the major problems is a massive influx of activated neurophils which damage both vascular endothelium and alveolar epithelium and result in massive pulmonary edema and impairment of surfactant function. Neutrophil proteinases (e.g., elastase) break down surfactant proteins. A potential therapeutic strategy in ARDS involves administration of both surfactant and antiproteinases (e.g., recombinant a I -antitrypsin). 

The reactive site of a 1 - AT is at the methionine residue, position 358. The sequence around the reactive center of several proteinase inhibitors, including oti-AT, antithrombin III, and several unrelated plant proteinase inhibitors, is strikingly similar. In fact, a i -AT, antithrombin III, and ovalbumin (a protein without known inhibitory function)... 

I. U. Khan and L. Polgfir. Purification and characterization of a novel proteinase, chymopapain S. Biochim. Biophys. Acta 760 350 (1983). 

Although in vitro, the cell wall-associated proteinase of the Lactococcus starters is quite active on )S-casein (and that from some strains on a i-casein also), in cheese, they appear to act mainly on casein-derived peptides, produced by chymosin from -casein or by plasmin from )S-casein. 

Figure 10.23 Water-insoluble and water-soluble peptides derived from a i-casein (A), aj2-casein (B) or -casein (C) isolated from Cheddar cheese DF = diafiltration. The principal chymosin, plasmin and lactococcal cell-envelope proteinase cleavage sites are indicated by arrows (data from T.K. Singh...

Exterkate, F. A., and Alting, A. C. (1993). The conversion of the a,i-casein-(l-23)-fragment by the free and bound form of the cell-envelope proteinase of Lactococcus lactis subsp. cremoris under conditions prevailing in cheese. Syst. Appl. Microbiol. 16,1-8. 

Kaminogawa, S., Yan T. R., Azuma, N., and Yamauchi, K. (1986). Identification of low molecular weight peptides in Gouda-type cheese and evidence for the formation of these peptides from 23 N-terminal residues of a,i-casein by proteinases of Streptococcus cremoris H61. J. Food Sci 51, 1253-1256. 

RATTANCHAI A, HIRONO I, OHiRA T, TAKAHASHi Y and AOKi T (2005) Peptidoglycan inducible expression of a serine proteinase homologue from kuruma shrimp (Marsu-penaeus japonicus). Fish Shellfish Immunol, 18,39-48. 

I thank Dr. John W. Donovan for helpful advice and discussions. Dr. Sipund Schwimmer for a critical reading of the manuscript, and Dr. Clarence A. I an for samples of purified potato proteinase Inhibitors I and II. 

Chaloupka, A. I. Severin, K. J. Sastry, H. KuderovA and M. StrnadovA, Differences in the Regulation of Exocellular Proteinase Synthesis during Growth and Sporogenesis of Bacillus Megaterium, Can. J. Microbiol., 28 1214 (1982). 

Proteinase A and proteinase A-inhibitor (I ) in yeast cells growing with and without glucose and harvested at early log phase... 

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