Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.4.22.32 (bromelain)
 1,025 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Protein inhibitors of cysteine proteinases possessing unusual properties have been found in soya (Glycine max) seeds. One of the inhibitor forms has also been detected in Bowman-Birk inhibitor preparations (both commercial and purified by affinity chromatography on chymotrypsin-Sepharose ones). A peculiarity of the inhibitors is that they irreversibly lose their activity in the presence of reducing agents; therefore their effects are normally unobserved under standard conditions of cysteine proteinase inhibitor assays. Soybean inhibitors are represented by two forms with pI of 5.9 and 3.2. The molecular mass of the inhibitor whose pI is equal to 5.8 is about 14 kDa. Both inhibitors suppress the activity of papain, ficin and bromelain.
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PMID:[Cysteine proteinase inhibitors from soy seeds]. 769 28

Two forms of stem bromelain (EC 3.4.22.4) were isolated from commercial, crude and chromatographically purified preparations of the enzyme by means of gel-filtration and cation-exchange liquid chromatography. These forms possess nearly identical secondary and tertiary structures, as judged from their circular dichroism (c.d.) spectra. The spectral characteristics of stem bromelain suggest that this enzyme belongs to the alpha + beta protein class, as other cysteine proteinases do. In agreement with these results, quantitative estimation of secondary structures yielded amounts similar to those for papain and proteinase omega. However, the bromelain c.d. curve is clearly distinguishable from those reported for papain and proteinase omega, on one hand, and that of chymopapain, on the other. Thus, it is apparent that there are at least three types of c.d. spectra associated with the family of cysteine proteinases.
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PMID:Circular dichroism of stem bromelain: a third spectral class within the family of cysteine proteinases. 819 20

Bromelain inhibitor VI from pineapple stem (BI-VI) is a unique double-chain inhibitor with an 11-residue light chain and a 41-residue heavy chain by disulfide bonds and inhibits the cysteine proteinase bromelain competitively. The structure of BI-VI in aqueous solution was determined using nuclear magnetic resonance spectroscopy and simulated annealing-based calculations. Its three-dimensional structure was shown to be composed of two distinct domains, each of which is formed by a three-stranded antiparallel beta-sheet. Unexpectedly, BI-VI was found to share a similar folding and disulfide bond connectivities not with cystatin superfamily inhibitors which inhibit the same cysteine proteinases but with the Bowman-Birk trypsin/chymotrypsin inhibitor from soybean (BBI-I). BBI-I is a 71-residue inhibitor which has two independent inhibitory sites toward the serine proteinases trypsin and chymotrypsin. These structural similarities with BBI-I suggest that they have evolved from a common ancestor and differentiated in function during a course of molecular evolution.
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PMID:Solution structure of bromelain inhibitor IV from pineapple stem: structural similarity with Bowman-Birk trypsin/chymotrypsin inhibitor from soybean. 861 27

The enzyme allergens Der p I and Der f I produced by the house dust mites Dermatophagoides pteronyssinus and D. farinae display partial sequence homology with other members of the cysteine proteinase superfamily. We report that certain widely used mouse mAbs against these Group I allergens indeed crossreact with the plant enzymes papain, bromelain and ficin. The recognition sites of these anti Group I mAbs comprise conformational and thermolabile epitopes involved in molding the catalytic center of the proteinases. Thus, the mAbs inhibit the enzymatic hydrolysis of specific chromogenic substrates by the Group I allergens, while specific cysteine proteinase inhibitors abolish the recognition of the enzymes by the mAbs. Similarly, activation of the thiol-proteases with L-cysteine abrogates their binding in the two-site mAb system, indicating that the mAbs recognize a proenzyme conformational peptide epitope. It follows that mAb-based assays for mite Group I components can neither detect the allergens after inactivation, nor in their fully activated forms.
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PMID:Monoclonal antibodies against Dermatophagoides group I allergens as pseudo-cystatins blocking the catalytic site of cysteine proteinases. 880 16

Cysteine proteinases are widely distributed among living organisms. According to the most recent classifications (Rawlings and Barrett, 1993, 1994), they can be subdivided on the basis of sequence homology into 14 or even 20 different families, the most important being the papain and the calpain families. The papain-like cysteine proteinases are the most abundant among the cysteine proteinases. The family consists of papain and related plant proteinases such as chymopapain, caricain, bromelain, actinidin, ficin, and aleurain, and the lysosomal cathepsins B, H, L, S, C and K. Most of these enzymes are relatively small proteins with Mr values in the range 20000-35000 (reviewed in Brocklehurst et al., 1987; Polgar, 1989; Rawlings and Barrett, 1994; Berti and Storer, 1995), with the exception of cathepsin C, which is an oligomeric enzyme with Mr approximately 200000 (Metrione et al., 1970; Dolenc et al., 1995). A number of cysteine proteinases are located within lysosomes. Four of them, cathepsins B, C, H and L, are ubiquitous in lysosomes of animals, whereas cathepsin S has a more restricted localisation (Barrett and Kirschke, 1981; Kirschke and Wiederanders, 1994). The enzymes, except cathepsin C, are endopeptidases (reviewed in Kirschke et al., 1995), although cathepsin B was found also to be a dipeptidyl carboxypeptidase (Aronson and Barrett, 1978) and cathepsin H also an aminopeptidase (Koga et al., 1992). Cathepsin C is a dipeptidyl aminopeptidase, but at higher pH it exhibits also dipeptidyl transferase activity (reviewed in Kirschke et al., 1995). Among the lysosomal cysteine proteinases, cathepsin L was found to be the most active in degradation of protein substrates, such as collagen, elastin and azocasein (Barrett and Kirschke, 1981; Maciewicz et al., 1987; Mason et al., 1989), arid cathepsin B the most abundant (Kirschke and Barrett, 1981). All the enzymes are optimally active at slightly acidic pH, although their pH optima for degradation of synthetic substrates vary from 5.5 for cathepsin L to 6.8 for cathepsin H (reviewed in Kirschke et al., 1995). Several other lysosomal cysteine proteinases, such as cathepsins N, T and K, are known, although their properties are less well characterised (reviewed in Kirschke et al., 1995). In particular cathepsin K has attracted recent interest (Bromme et al., 1996; Shi et al., 1995; Bossard et al., 1996; Drake et al., 1996) and was found to be expressed specifically in osteoclasts (Drake et al., 1996) with properties similar to cathepsin L (Bossard et al., 1996).
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PMID:Structural and functional aspects of papain-like cysteine proteinases and their protein inhibitors. 916 64

The amino acid sequences of ananain (EC3.4.22.31) and stem bromelain (3.4.22.32), two cysteine proteases from pineapple stem, are similar yet ananain and stem bromelain possess distinct specificities towards synthetic peptide substrates and different reactivities towards the cysteine protease inhibitors E-64 and chicken egg white cystatin. We present here the complete amino acid sequence of ananain and compare it with the reported sequences of pineapple stem bromelain, papain and chymopapain from papaya and actinidin from kiwifruit. Ananain is comprised of 216 residues with a theoretical mass of 23464 Da. This primary structure includes a sequence insert between residues 170 and 174 not present in stem bromelain or papain and a hydrophobic series of amino acids adjacent to His-157. It is possible that these sequence differences contribute to the different substrate and inhibitor specificities exhibited by ananain and stem bromelain.
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PMID:Complete amino acid sequence of ananain and a comparison with stem bromelain and other plant cysteine proteases. 935 53

Three protein inhibitors of proteolytic enzymes with molecular weights 21, 22, and 23 kD were isolated from potato tubers (Solanum tuberosum L.) by ammonium sulfate precipitation followed by gel and ion-exchange chromatography. The 21- and 22-kD proteins were shown to be serine proteinase inhibitors with different specificities. The 21-kD protein inhibits human leucocyte elastase and trypsin effectively, but it is less effective towards chymotrypsin. The 22-kD protein is an inhibitor of cysteine proteinases and suppresses the activities of papain, ficin, and bromelain with the same affinities. None of the isolated proteins inhibit subtilisin, pepsin, or cathepsin D. The 21-kD protein consists of two disulfide-linked polypeptide chains with molecular weights of 16.5 +/- 1 kD and 4.5 +/- 1 kD. The 22-kD and 23-kD proteins have a single polypeptide chain. The N-terminal 22-25 amino acid sequences of these three proteins were determined. These sequences have significant homology to other plant inhibitors from the Kunitz soybean inhibitor superfamily.
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PMID:Potato tuber protein proteinase inhibitors belonging to the Kunitz soybean inhibitor family. 948 70

Two forms of an acidic bromelain proteinase isolated from crude bromelain, an extract from pineapple stem, were found by a two-step FPLC purification procedure. The basic main components were removed by cation exchange chromatography and the breakthrough fraction was further resolved by anion exchange chromatography into 15 protein fractions, only two of which, called SBA/a and SBA/b, were proteolytically active. These components were characterized by electrospray mass spectroscopy (ESMS), isoelectric focusing, N-terminal amino acid sequence analysis, monosaccharide analysis, and enzymatic parameters. The molecular masses of SBA/a and SBA/b were determined by ESMS to be 23,550 and 23,560, respectively. The isoelectric points (pI) of the two bands of SBA/a were 4.8 and 4.9; SBA/b focused as a single band at pI = 4.8. Partial N-terminal amino acid sequences (11 residues) were identical to SBA/a and SBA/b and identical with those of stem bromelain, the basic main proteinase of the pineapple stem, and fruit bromelain, the acidic main proteinase of the pineapple fruit. Both components are highly glycosylated; hydrolysis of SBA/a yielded about twofold more monosaccharide per protein than SBA/b. The comparison of the catalytic properties of SBA/a with those of SBA/b revealed no relevant differences in the hydrolysis of three peptidyl-NH-Mec substrates and in the inhibition profiles using chicken cystatin and E-64, indicating that these components can be considered as two forms of a single enzyme. Both forms are scarcely inhibited by chicken cystatin and slowly inactivated by E-64, hence are nontypical cysteine proteinases of the papain superfamily.
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PMID:Isolation and characterization of two forms of an acidic bromelain stem proteinase. 961 88

A study was made on the effect of vanadium, in both the tetravalent state in vanadyl sulphate and in the pentavalent state in sodium meta-vanadate, and ortho-vanadate, on the proteolysis of azocasein by two serine proteases, trypsin and subtilisin and two cysteine proteases bromelain and papain. Also the proteolysis of bovine azoalbumin by serine proteases was considered. An inhibitory effect was present in all cases, except meta-vanadate with subtilisin. The oxidation level of vanadium by itself did not determine the inhibition kinetics, which also depended on the type and composition of the vanadium containing molecule and on the enzyme assayed. The pattern of inhibition was similar for proteases belonging to the same class. The highest inhibition was obtained with meta-vanadate on papain and with vanadyl sulphate on bromelain.
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PMID:Vanadium inhibition of serine and cysteine proteases. 1035 62

Data on study of action plasma inhibitors on activity of pancreatic proteolytic enzymes (trypsin, chymotrypsin) and plant proteinases (papain, bromelain), included in composition of enzyme mixes, used for orally application are submitted. It is established, that serine proteases are more sensitive to inactivation of plasma inhibitors, than cysteine enzymes. Main inhibitor of the papain and bromelain is alpha-2-macroglobulin in complex with which they preserve significant part of initial activity. A high-sensitivity method of determination of activity enzyme combinations, enabling to detect nanograms of them in presence of plasma inhibitors is offered. It can be used for study pharmacokinetic and optimization of enzyme mixes application in clinical practice.
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PMID:[Effect of blood plasma inhibitors on activity of serine and cysteine proteinases]. 1040 46


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