Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.4.22.6 (chymopapain)
 407 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

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

The cysteine-proteinase chymopapain from Carica papaya L. is used for chemonucleolysis of damaged human intervertebral spinal discs. The purification of this enzyme is difficult. To overcome these problems, we were looking for a substitute among the cysteine-proteinases of Carica candamarcensis Hook. The latex from unripe fruits was collected in an aqueous solution of methylethanethiolsulfonate to prevent proteolytic activities. The soluble fraction of the lypophilized product provided four enzymatically active peaks (CC-I-CC-IV) during chromatography on CM-Sephadex C-50 in sodium acetate buffer, pH5.0. They could be further purified by rechromatography under similar conditions. The isolated enzymes have been characterized by PAGE, analysis of the Fourier transform infrared spectra, preliminary studies of their specificities as well as a comparison of the N-terminal amino-acid sequences up to position 43. CC-III proved to be glycosylated. CC-I and CC-III from Carica candamarcensis Hook are suggested to correspond to papain and chymopapain from Carica papaya L., respectively.
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PMID:Isolation and preliminary characterization of the cysteine-proteinases from the latex of Carica candamarcensis Hook. 821 2

Differential scanning calorimetry (DSC) was employed to study the thermal unfolding of chymopapain (EC 3.4.22.6) and papain (EC 3.4.22.2), two highly homologous cysteine proteinases from Carica papaya. Under all pH conditions used, both enzymes showed irreversible thermal denaturation. However, results from experiments performed at two different scanning rates suggest that interpretation of data in terms of equilibrium thermodynamics is not unreasonable. For papain, the ratio of calorimetric (delta Hcal) to van't Hoff (delta HvH) enthalpies approximated to 2.0. This value indicates that papain domains unfold almost independently, as it has been reported previously. In contrast, chymopapain displayed a more cooperative behavior with a delta Hcal to delta HvH ratio of 1.3-1.4. DSC curves were analyzed in terms of a mechanism that includes domain-domain interactions. The results showed a negligible interdomain free energy in the case of papain, but a significant value of approx. 1.0 kcal/mol (1 cal = 4.184 J) for chymopapain. These two proteins also differed in the unfolding heat-capacity change, delta Cp, which suggests that their native structures bury different amounts of nonpolar surface area.
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PMID:Cooperativity in the unfolding transitions of cysteine proteinases. Calorimetric study of the heat denaturation of chymopapain and papain. 821 80

Thermal denaturation of four Carica papaya cysteine proteinases (papain, chymopapain, papaya proteinases 3 and 4) was studied as a function of pH using high-sensitivity differential scanning calorimetry. The ratios of calorimetric enthalpy to Van't Hoff enthalpy suggest that, for all these proteins, denaturation occurs as a non two state process, via an intermediate structure. Differences in the thermal stabilities of the proteinases; chymopapain > papaya proteinase 3 > papain > papaya proteinase 4, were correlated to their amino acid sequence to explain the observations in terms of mobility and specific residue mutation. Three-dimensional structures of papain and papaya proteinase 3 were similarly used to illustrate the influence of atomic mobility on stability.
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PMID:Factors effecting the thermostability of cysteine proteinases from Carica papaya. 850 84

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

In the tropical species Carica papaya, the articulated and anastomosing laticifers form a dense network of vessels displayed in all aerial parts of the plant. Damaging the papaya tree inevitably severs its laticifers, eliciting an abrupt release of latex. Besides the well-known cysteine proteinases, papain, chymopapain, caricain and glycyl endopeptidase, papaya latex is also a rich source of other enzymes. Together, these enzymes could provide an important contribution to plant defence mechanisms by sanitising and sealing the wounded areas on the tree.
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PMID:Revisiting the enzymes stored in the laticifers of Carica papaya in the context of their possible participation in the plant defence mechanism. 1136 Oct 91

We describe the purification of a cysteine proteinase from latex of Carica candamarcensis, hereby designated CC23. The enzyme has been purified by ion-exchange chromatography and behaves electrophoretically as a monomer of M(r) 23,000 and optimal pH of 8.0. It displays a basic isoelectric point, has one cysteine residue in the active site by titration with E-64, confirmed by DNA sequencing, and responds to proteinase inhibitors as a classic cysteine proteinase. The K(m) and k(cat)/K(m) for CC23 using BAPNA were respectively 14.7 +/- 1.8 x 10(-4) M and 1.3 x 10(3) M(-1) s(-1). Therefore, the catalytic efficiency of CC23 is sixfold higher than that of CC-I, another proteinase from the same plant. DNA primers were designed to amplify by PCR a genomic sequence related to this enzyme. An 895-bp DNA fragment was cloned and sequenced. It shows strong homology with chymopapain isoform IV from C. papaya. The translated sequence is similar to that of chymopapain isoform II (73%) and CC-III (77%) from C. candamarcensis.
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PMID:Purification of a cysteine proteinase from Carica candamarcensis L. and cloning of a genomic putative fragment coding for this enzyme. 1143 1

In defoliated grasses, where photosynthesis is reduced due to removal of leaf material, it is well established that remobilization of nitrogen occurs from both older remaining leaves and roots towards the younger growing leaves. In contrast, little is known about the movement of nitrogen within intact grass plants experiencing prolonged inhibition of photosynthesis. We tested the following hypotheses in Festuca rubra L. ssp. rubra cv. Boreal: that both reduction of the atmospheric CO2 concentration and defoliation (1) induce mobilization of nitrogen from roots and older leaves towards growing leaves and (2) elicit similar directional change in the abundance of proteins in roots and older leaves relevant to the process of nitrogen mobilization including, glutamine synthetase (GS), EC 6.3.1.2; papain, EC 3.4.22.2; chymopapain, EC 3.4.22.6; ribulose bisphosphate carboxylase/oxygenase (Rubisco), EC 4.1.1.39; and the light harvesting complex of photosystem II (LHCPII). After growth at ambient atmospheric CO2 concentration, plants of F. rubra were subject to atmospheres containing either ambient (350 micro l l-1) or deplete (< 20 micro l l-1) CO2. Concurrently, plants were either left intact or defoliated on one occasion. Steady state 15N labelling coupled with a series of destructive harvests over a 7-day period enabled changes in the nitrogen dynamics of the plants to be established. Proteins pertinent to the process of nitrogen mobilization were quantified by immunoblotting. Irrespective of defoliation, plants in ambient CO2 mobilized nitrogen from older to growing leaves. This mobilization was inhibited by deplete CO2. Greater concentration of Rubisco and reduced chymopapain abundance in older remaining leaves of intact plants, in deplete compared with ambient CO2, suggested the inhibition of mobilization was due to inhibition of protein degradation, rather than to the export of degradation products. Both deplete CO2 and defoliation induced nitrogen mobilization from roots to growing leaves. In plants at ambient CO2, defoliation did not affect nitrogen uptake or its allocation. Therefore in F. rubra nitrogen mobilization can occur independently of any downregulation of nitrogen uptake. This suggests either different signal compounds may act to downregulate uptake and upregulate mobilization, or if one particular signalling compound is used its concentration threshold differs for induction of mobilization and downregulation of uptake. The abundance of the cysteine proteases papain and chymopapain was low in roots suggesting that they were not involved in protein degradation in this tissue.
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PMID:Reduced atmospheric CO2 inhibits nitrogen mobilization in Festuca rubra. 1220 63

Chymopapain, one of the four cysteine proteinases of papaya latex, has milk clotting and proteolytic activity. It is mainly used to treat prolapsed intervertebral discs. This paper introduced the preparation of polyclonal antibody of partially purified chymopapain and the identification of the antibody specificity. The polyclonal antibody provides a basis for the further researches and applications of chymopapain.
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PMID:[The preparation and identification of rabbit's antibody of chymopapain]. 1268 52


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